Asian Journal of Applied Science and Engineering (AJASE)

Asian Journal of Applied Science and Engineering, Volume 1, No 2 (2012) ISSN 2305-915X

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Vol. 1, No. 2/2012



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ASIAN JOURNAL OF APPLIED SCIENCE AND ENGINEERING

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Volume 1, Number 2/2012 (Second Issue)

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Dr. Mohammad Anwar Hossain, Assistant Professor, Department of Genetics & Plant Breeding, Bangladesh Agricultural University, Mymensingh, Bangladesh

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Asian Journal of Applied Science and Engineering

Blind Peer-Reviewed Journal

Volume 1, Number 2/2012 (Second Issue)

Contents

1. Effect of Fixed Horizontal Shading Devices in South Facing Residential

Buildings at Dhaka, Bangladesh

09-19

Saiful Hasan Tariq, & Mahbuba Afroz Jinia

2. Transformation and changing trend of urban living spaces: A case of Dhaka city 20-30

Maher Niger

3. Transformation of Dhanmondi Residential Area- Causes, Effects and

Proposal to Rejuvenate

31-47

Sonya Afrin, Ishrat Zerin, Subarna Sharmin, &

Kazi Murshida Morshed

4. Performance Analysis of UMTS Cellular Network using Sectorization

Based on Capacity and Coverage in Different Propagation Environment

48-55

M. S. Islam, Jannat-E-Noor, & Soyoda Marufa Farhana

5. Effect of Injection Pressure on the Perfomance and Emissions of Nerium

Biodiesel Operated Diesel Engine

56-64

Dr. Vinai K.Singh

6. Effects of Excess Bi2O3 on the Properties of La- doped Bismuth titanate

(Bi4Ti3O12) Ferroelectric Ceramics

65-69

Md. Aminul Islam, Dr. Abdul Gafur, & Dr. M. Saidul Islam

7. Relativistic Rule of Multiplication of Velocities Consistent with Lorentz – Einstein

Law of Addition and Derivation of the Missing Equations of Special Relativity

70-83

Dr. M.O.G. Talukder, & Dr. Mushfiq Ahmad

8. Spatial Environmental Impact on Land Degradation in Bangladesh 84-90

Md. Mahmudur Rahman, Md. Mostafizur Rahman,

Tamanna Akter Tanu, & Md. Masuder Rahman

AJASE Publish

Online and Print

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Effect of Fixed Horizontal Shading Devices in

South Facing Residential Buildings at Dhaka,

Bangladesh

Saiful Hasan Tariq & Mahbuba Afroz Jinia

Lecturer, Dept. of Architecture, Stamford University Bangladesh

ABSTRACT

External shading devices have been utilized very extensively in the residential buildings in the tropics to reduce the amount of solar radiation occurring in the buildings. It is now widely accepted that architects should encompass the environmental task of reducing fossil fuel energy consumption in response to climate change. The study focuses on the minimum depth required for the fixed horizontal shading device for optimum shading performance at south façade for commonly used opening sizes in the residential buildings in Dhaka city. Particular emphasis has been given on the opening size, depth of the shading device, vertical shadow angle during the warmest part of the day of warmest seasons and the thermal performance for using different depth of shading devices in various opening sizes. Two residential buildings are fundamentally chosen as topic for this study. The units having two different sizes of opening and shading systems are taken as the study element. Difference between maximum outdoor temperature and indoor temperature and the shadow patterns are taken into account during the warmest part of the day to identify the parameters for existing thermal performance due to shading devices. The field survey was conducted in a sunny day to measure the temperature difference between indoor and outdoor and the direct solar radiation in both study models. The shadow simulation of the case studies were conducted by the Sketch up v7.0 having location data and based on the dates and times of the warmest months. The simulation is more visual than analytic. This paper is an outcome of the study which encompasses the efficient shading device design strategy to reduce direct solar exposure on the openings at south façade along with the case studies in the context of Dhaka, Bangladesh and its effect on building performance in terms of thermal performance.

Key words: Shading devices, Vertical shadow angle, Thermal performance, Design strategy.

INTRODUCTION

The most significant factor affecting the architectural environment in the tropical region is solar energy. Throughout the year, solar energy impinges on the building which influences either its inside or outside climate. To control the effect of solar energy on the Indoor environment, it is



usual to concentrate on the role played by the building skin and fenestration, which act as a filter between the outdoor conditions and those within the building. Focusing on the fenestration, which is the critical point of indoor heat gain, heat transfer can occur by radiation, ventilation (infiltration), conduction, and convection. Fenestration can contribute up to 22% of energy consumption in residential buildings (Al-Mofeez et al, 1991). External shading devices can be utilized to block the solar radiation before it reaches the indoor environment. The greatest source of heat gain can be the solar radiation entering through an opening. This could, in fact, increase the indoor temperature, far above the outdoor temperature even in moderate climates, which is known as the ―Green House Effect‖ (Koenigsberger et al, 1973). Window glasses are particularly transparent for short wave infra-red radiation by the sun, but almost opaque for long wave radiation emitted by objects in the room. As a result the heat, once it has entered through a window, is trapped inside the building. As the south façade gets maximum exposure to the solar radiation during the warmest part of the day, the openings in this façade requires properly designed shading devices to minimize the solar heat gain. Horizontal shading devices are appropriate to protect the windows from solar heat gain at south orientation. It works efficiently from 10 A.M. to 2 P.M. when the sun is opposite to the window pane and at a high altitude (Anisur Rahman, 2007). The study intends to set a parameter for the minimum required depth of the fixed horizontal shading device at south façade for commonly used opening sizes in the residential buildings in Dhaka city.

OBJECTIVES OF THE RESEARCH:

The study focuses on the minimum depth required for the fixed horizontal shading device for optimum shading performance at south façade for commonly used opening sizes in the residential buildings in Dhaka city. Particular emphasis has been given on the opening size, depth of the shading device, vertical shadow angle during the warmest part of the day of warmest seasons and the thermal performance for using different depth of shading devices in various opening sizes. The objective of the study can be summarized as follows: Practical understanding of the relationship between vertical shadow angle (VSA) and

depth of overhang of fixed horizontal shading devices. To find out the parameter for the optimum depth of the fixed horizontal shading device at

south façade for commonly used opening sizes. To explore the ideal shading device for South facing residential building with optimum

thermal performance.

METHODOLOGY:

Two residential buildings are fundamentally chosen as topic for this study considering their long time use by the inhabitants. The units having two different sizes of opening and shading systems are taken as the study element. Difference between maximum outdoor temperature and indoor temperature and the shadow patterns are taken into account during the warmest part of the day to indentify the parameters for existing thermal performance due to shading properties. The field survey was conducted in a sunny day to measure the temperature difference between indoor and outdoor and the direct solar radiation in a selected south oriented room during the warmest part of the day in both study models. The temperature data and vertical shadow angle of the warmest months were taken by calculating the sun path diagram from the ECOTECT v5.20. The shadow simulation of the case studies were conducted by the Sketch up



v7.0 having location data and based on the dates and times of the warmest months. The simulation is more visual than analytic. From March to October this region faces pre-monsoon, monsoon and post monsoon seasons, which are the warmer seasons in the local climate. From 12 P.M. to 2P.M is considered as the hottest part of the day in these months. The dates for simulation have been selected randomly as 21st march, 21st June and 22nd September. The selection of months has been made on the basis of pre-monsoon, monsoon and post monsoon seasons and the selection of dates made randomly. The 3d visual analysis of Sketch up shadow simulation is made on these mentioned dates in three different time segments from 12 P.M. to 2P.M. The outcome of the simulation is then compared with the ideal ratios mentioned in literature review. The thermal performance was measured on the date of 21st and 22nd September in similar sky condition because of time constrains. At the End, the ideal condition is picked based on the thermal performance in indoor due to proper shading system by comparing the study models.

Diagram: 1.Diagram of the research process, Source: Author

CLIMATE OF BANGLADESH

Bangladesh has a subtropical monsoon climate characterized by moderately warm temperature, high humidity and seasonal variations in rainfall. According to Atkinson’s widely used classification it can be categorized as warm-humid (Koenig Berger et al, 1973). With the exception of the relatively dry western part of Bangladesh, most of the parts of the country receive 200mm of average monthly rain fall. Generally, the climate has short and dry winters with humidity between 45% and 71% while the summer is long and wet and then the humidity lies between 84% and 92%. Meteorologically Bangladesh has four distinct seasons. Winter, from December to February (mean temperature between12oC and 28oC), Pre-monsoon, March to May (20oC and 35o C), Monsoon from June to September (25oC and 32oC) Post-monsoon covers October and November (17oC and 31oC).



Table: 1. Classification of seasons

Bangla

Calendar

Months

Traditional

seasons

Meteorological

seasons

Gregorian

calendar

months

Chaitra Bashanta Pre- monsoon (hot-dry) March

Baishakh Grisha Pre-monsoon (hot- dry) April

Jaishtha Grisha Pre-monsoon (hot-dry) May

Ashaar Barsha Monsoon (hot-wet) June

Srabon Barsha Monsoon (hot-wet) July

Bhadra Sharat Monsoon (hot-wet) August

Aswin Sharat Monsoon (hot-wet) September

Kartik Hemanta Post-monsoon (hot-wet) October

Agrahayon Hemanta Post-monsoon (hot-wet) November

Poush Sheet Winter December

Magh Sheet Winter January

Falgun Bashanta Winter February

WEATHER OF DHAKA

Dhaka is located in central Bangladesh at 23o 42’0‖N 90o 22’30‖E. Dhaka experiences a hot, wet and humid tropical climate. The city has a distinct monsoonal season, with an annual average temperature of 25oC and monthly means varying between 18oC in January and 32oC in May. Approximately 87% of annual average rainfall of 2,123 millimeters occurs between May and October.

Table: 2. Climate data for Dhaka (source: Weather base)

LITERATURE REVIEW

OBJECTIVES OF SHADING

Shading the glass affects the quantity of incident radiation and hence modifies both the heat flow to the interior and indoor temperatures. It is useful to set out the purpose of shading in some detail (Steemers et al, 2002). They are as follows,

To minimize the total solar energy entering a room and thereby reduce the average temperature of the room

To prevent sunlight from falling directly onto occupants, resulting in an effective increase of temperature of between 3oC and 7oC

To prevent the brightly lit outside surface, clouds or sun.



CALCULATION FOR OPTIMUM SHADING

It has been found from the investigation that horizontal shading devices were efficient at south elevation only. These shading devices are appropriate to protect windows from solar heat gain at south orientation. It works efficiently from 10 A.M. to 2 P.M. when the sun is opposite to the window pane and at a high altitude. (Anisur Rahman, 2007)

The depth of the overhang depends on the opening height and it is independent of the window width. The performance of the horizontal shading device increases with the increase of the depth of the overhang. The important factor is the ratio between the depth of the overhang and the height of the opening. (Anisur Rahman, 2007)

For optimum shading, the ratio between depth of overhang and height of the opening is, D = 7/16 x H Where, D = depth of overhang H = height of opening

Fig: 1.schematic diagram showing parameters of horizontal shading device, Source: Anisur Rahman, 2007

The ratio between the side offset from opening edge of overhang and height of the opening is , W = H/2 Where, W = Side offset from opening edge H = height of opening

Fig: 2.schematic diagram showing parameters of horizontal shading device, Source: Anisur Rahman, 2007

D= 716H

H

sun

W=H/2 W=H/2

H



For large height of openings, the shading devices require larger overhangs. Those overhangs transforms into verandahs in most of the cases of fixed overhangs. Another way of minimizing effective height of openings is by using several shorter depth overhangs on the window pan instead of one large overhang. This system is not popular among the residential buildings as it splits the vista through the openings.

Optimum shading can also be determined by the ratio between Depth of overhang and opening height, D = H / tanØ Where vertical shadow angle = tanØ

Fig: 3.schematic diagram showing parameters of horizontal shading device, source: (Koenigsberger et al, 1973).

ANALYSIS

Both the study models have 30’ wide road at south side (front) and a vacant opposite plot. These study models has been selected for getting optimum solar exposure at south façade without any obstacle during whole day. Having different types of opening and shading systems were another selection criteria. Both of the units used the most common types of shading systems usually practiced in local context. To be more specific in temperature data collection, one south oriented room has been selected as field survey model and simulation model as well. The field survey data has been taken in two back to back days with similar climatic condition and in clear sunny day.

STUDY UNIT-1

Study unit-1 is the 2nd floor unit of a Govt. officers’ colony at Malibagh, Dhaka. A south-East corner bed room has been selected for shadow simulation and field data collection. The overhang at roof slab was not taken into account as it puts no impact on the glass surface.

H

sun

D

VSA = tanØ



The size of the opening at south façade is 6’ x 4.5’. The depth of overhang is 2’ and the sill level is at 2.5’ level from floor.

Fig: 4.Plan, section and image of Study Unit-1, source: Author

At first, the requirement of overhang for an opening height of 4.5’ has been checked. D = 7/16 x 4.5 = 1.96’ As the existing overhang is 2’; so, theoretically it should be adequate for optimum shading performance during the warmest part of the day. The minimum requirement has also been checked by the calculation of vertical shadow angle. Minimum vertical shadow angle data has been taken between 12 P.M. to 2 P.M. for the analysis.

Table: 3. Calculating depth of overhang from Vertical shadow angle (VSA) data

Date Minimum VSA (tanØ)

from 12 P.M. TO 2 P.M.

Opening height

H

Minimum Depth of overhang

D = H / tanØ

21st March 113.7 o 4.5’ or 54 inch 1.97’ < 2’

21st June 82.8 o 4.5’ or 54 inch 0.56’ < 2’

22nd

September

112.8 o 4.5’ or 54 inch 1.89’ < 2’

The simulation study has been made in the dates of 21st march, 21st June and 22nd September in three different time segment from 12 P.M. to 2 P.M. Simulation study shows the visual outcome of shading performance of the Shading devices.

N

sun

2'-6"

4'-6"

2'



Fig: 5.sketch up shadow simulation study shows the shading performance of the shading device, source: Author

The simulation study shows that the 2’ overhang of shading device is minimum required depth for shading system where the opening height is 4.5’. Having this depth of overhang the glass surface gets the protection from direct solar exposure during the warmest part of the day in a clear sky condition. The sectional perspectives of the study unit shows the shaded interior space, which means less heat gain due to direct solar radiation and cooler indoor environment than the outdoor. The temperature data was taken on 22nd September and Outdoor temperature was measured at 33oC while indoor temperature was measured in constant air change at 30.5oC during the time segment from 12 P.M. to 2 P.M.

STUDY UNIT-2

Study unit-2 is the 4th floor unit of an apartment building at Uttara, Dhaka. A south-West corner bed room has been selected for shadow simulation and field data collection. The opening at west side in the study unit was not taken into account as it gets no solar exposure from west due to adjacent apartment building. The size of the opening at south façade is 5’ x 7’. The depth of overhang is 3.33’ and the opening is used as an access way to the verandah which is providing support for the shading device.

Fig: 6.Plan, section and image of Study Unit-2, source: Author



At first, the requirement of overhang for an opening height of 7’ has been checked. D = 7/16 x 7’ = 3.06’ As the existing overhang is 3.33’; so, theoretically it should be adequate for optimum shading performance during the warmest part of the day. The minimum requirement has also been checked by the calculation of vertical shadow angle. Minimum vertical shadow angle data has been taken between 12 P.M. to 2 P.M. for the analysis. Table: 4. Calculating depth of overhang from Vertical shadow angle (VSA) data

Date Minimum VSA (tanØ)

from 12 P.M. TO 2 P.M.

Opening

Height H

Minimum Depth of

overhang D = H / tanØ

21st March 113.7 o 7’ 3.07’ < 3.33’

21st June 82.8 o 7’ 0.88’ < 3.33’

22nd September 112.8 o 7’ 2.94’ < 3.33’

The simulation study has been made in the dates of 21st march, 21st June and 22nd September in three different time segment from 12 P.M. to 2 P.M. Simulation study shows the visual outcome of shading performance of the Shading devices.

Fig: 7.sketch up shadow simulation study shows the shading performance of the shading device, source: Author

The simulation study shows that the 3.33’ or 3’-4‖ overhang of shading device is minimum required depth for shading system where the opening height is 7’. Having this depth of overhang the glass surface gets the protection from direct solar exposure during the warmest part of the day in a clear sky condition. The sectional perspectives of the study unit shows the shaded interior space, which means less heat gain due to direct solar radiation and cooler indoor environment than the outdoor.



In the study unit-2, a larger opening at south allows vista, good airflow and optimum daylight. An opening size of 5’wide and 7’ height requires larger over hang, which is known from the theoretical perspective. Larger overhang required more structural support from the cantilevered floor. The extension of the floor space beneath the overhang was transformed into verandah and the larger glass opening worked as the access way to the verandah as well. The temperature data was taken on 21st September and Outdoor temperature was measured at 33.0oC while indoor temperature was measured in constant air change at 29.5oC during the time segment from 12 P.M. to 2 P.M.

DISCUSSION

Both of the Study units used the most common types of shading systems usually practiced in Bangladesh. The Study unit-1 had the fixed horizontal shading device cantilevered from the lintel level of the opening. Both theoretical calculation and visual simulation study shows that 2’ over hang is the minimum required shading depth for the opening of 4.5’ height. The performance of the shading device is also cross checked by taking the temperature data which shows a 2.5oC temperature difference from out door to indoor in constant air change situation. In the case of study unit-2 the space beneath the fixed horizontal shading device has been transformed in to verandah because of large and accessible opening size. The verandah floor slab provided support system for the large overhang. The verandah also works as a heat buffer zone from the outside and keeps the indoor temperature cooler than outdoor. The temperature data shows a 3.5oC temperature difference from out door to indoor in constant air change situation during the warmest part of the day. The indoor of study unit-2 is also found to be 1oC cooler than the Study unit-1 while the outdoor temperature was same (33oC). Reduced indoor temperature signifies reduced energy consumption for thermal comfort. Therefore, for full height openings (up to lintel level) at south façade, it can be recommended to use cantilever verandahs with required depth for shading in the context of Bangladesh. Both the study units show optimum shading performance during the warmest times of the warmest months in the year. Either fixed horizontal shading or the cantilever verandah, both of them are suitable for the context of Bangladesh, if properly designed by understanding the relationship between the height of the opening and the depth of the overhang.

CONCLUSION

This study intended to set a parameter for the required depth of the fixed horizontal shading device at south façade for commonly used opening sizes in the residential buildings in Dhaka city. Two study units were taken into account for field survey and simulation study to test the performance of the shading devices. The Thermal performance due to shading properties during the warmest part of the day was found satisfactory in both study units. From the temperature data, it is notable that proper use of shading devices may have significant impact on thermal performance as well as reduced energy consumption to achieve the comfort situation in built environment. Further study in this topic may enrich the field of sustainable architecture and will put significant impact on the movement of low energy consumption.

REFERENCES

Koenigsberger, O.H. (1973), Manual of Tropical Housing and Building Design,

Part-1, Orient Longman.p.102-113

B. Givoni (1969), Man, Climate and Architecture



Anisur Rahman (2007), Performance Evaluation of Shading Devices Used in Tall Office Buildings of

Dhaka City, M. Arch. Thesis, (unpublished) Department of Architecture, Bangladesh

University of Engineering and Technology, Dhaka.

Al-Mofeez, Ibraheem Abdul (1991), Insulation in the Opaque Envelope: Effects on Thermal Performance of

Residential Building in Hot-arid Climates, Dissertation for degree of Doctor of Philosophy in

The Texas A&M University, UMI dissertation information service, Michigan.

APPENDIX



Transformation and changing trend of urban

living spaces: A case of Dhaka city

Maher Niger

Lecturer, Department of Architecture, Ahsanullah University of Science and Technology, Dhaka,

Bangladesh

ABSTRACT

With the changing communication technology, the traditional living spaces need to be redefined with the changing forms and functions. The living space is no more a very private space but a space within the space and a window to the virtual communities. Houses have changed as people are becoming physically and socially more integrated with the outside world. Houses being built now differ radically from traditional houses in many aspects, from their material and structure to style and appearance. With growing urban living spaces, houses being built in most areas are becoming less influenced by existing traditions and more influenced by popular trends and communication patterns. This study aims to examine the transforming changes and trends of the urban living spaces by comparing houses built in different time periods in order to trace the factors implying the changes. Some of the changing factors of trend and adaptation includes; cultural practice, family size, technological changes, and influence of land value. The case of Dhaka has been put forth, focusing on influences from outside world, distinguishing globalization from a more general process of modernization. This paper attempts to track the changes of domestic spaces over time in underlying functional structures. This paper focuses on how changes have come about within the domain of the residence, discussing it in four broad phases: the urban beginnings, the mid twentieth century, the post independence and the present developer housing phase. Spatial patterns from various house types not only illustrate different domestic experience but also identify the impact of physical transformation by the process of urbanization. Keywords: Changing Factors, Traditional, Trend, Urban living space, Urbanization.

INTRODUCTION

Living spaces are a special kind of private space, where one seeks comfort and rest, among other members of the family or by oneself if the person is single. The intimacy of the home first lies in the simple fact that it is a delimited space, whose borders are recognized as such by outsiders as well as insiders. Apartments are delimited by walls of course, but houses, too, are more often than not surrounded by some kind of wall or fence, with a gate that can be locked.



If not, there is always an invisible line that separates it from public space and of which neighbors are fully aware. The interior space, whether of a house or an apartment flat, is the heart of the domestic space, which extends to some degree to the outskirts of the building. Houses customarily derive pattern and style from many factors, such as physical setting, topological climate, social, culture, symbolic meaning and lifestyles. Around the world, most of houses reflect the basic needs in a particular locality. Both physical and socio-cultural factors that shape houses have been changed and modified over time. In recent years, a global phenomenon has overwhelmingly influenced the transition of local contexts from traditional to modern housing by introducing new processes of communication technology. Factors that determine cultural change in houses become more complex since there are various ways to explore the relationship between cultural content and the design of built spaces, as in technology, economics, and symbolism and sociopolitical aspects, and they are based on different value systems. The design of houses is a direct expression of changing values, images, perceptions and ways of life. This study focuses on the physical transformation of living spaces as a way to define the connection and the understanding of the relations between built spaces and culture. The investigation of evolution of domestic space by tracing the development of spatial pattern over time indicates culturally linked phenomena among the housing patterns and helps to identify the problems of consistency and transformation of pattern.

THE IMPACTS OF URBANIZATION PROCESS

The design of space is created basically to accommodate people’s needs; it changes from time to time in order to correspond with a new lifestyle and contextual settings. Indigenous design judged as being the best and the most efficient response to topographic, climatic and economic constraints have been influenced by a global phenomenon. Because the urbanization process affects traditional culture, the impact of these changes becomes physically evident, particularly in most rural settlements and vernacular houses. As in many Third World countries, the transition of living spaces in Dhaka from traditional patterns to what is considered as essentially different from existing local patterns is a significant turning point in the development of living pattern. Such transitions have been mentioned by many scholars as unsuccessful and responsible for shortcomings (Brolin, 1976.) (Lang, 1987.). It is argued that the transition is not smooth and successful because both house patterns do not support the same lifestyle and cultural content. As indicated in many housing studies, Le Corbusier’s design of Chandigarh in India (Kalia, 1987), the resettlement of Cappadocia cave dwellers in Turkey to subsidized housing provided by the government (Emge, 1992.) And the urban housing projects in African countries (Potash, 1985. ) are a few among a large number of examples that point out the problems of transitional process resulting from the differences in spatial design. There are many external factors driving regional development, such as modern culture, political systems, social and family structure corresponding with global phenomena. Architectural evolution has also reflected these trends. The transition has been causing a discrepancy between the traditional lifestyle and modern housing design. The transition from the traditional house form and space is a sudden shift, including the adoption of new style and materials that appear to transform spatial and cultural aspects of houses. Newly acquired house styles, associated with patterns unfamiliar in local contexts, reveal a profound adaptation of the interior arrangement and user’s domestic routines. In general, house styles and arrangements have developed across time in order to accommodate new requirements based on the change of lifestyle and attitudes. The new house



style design and spatial arrangement influence physical alterations, which consequently affect the interactions among occupants and their daily routines. The way domestic space organizes in built form is the way in which people manipulate spaces, select their choices and adapt an existing design to support personal preference and their behavior. This study intends to examine how the change of living spaces accounts for the way it is used, particularly in the place where both traditional and popular patterns are merging.

HOUSES AS SETS OF SECTORS

House organization has changed through time, constantly adapting to respond to requirements imposed by social relations, codes of behavior and family structure, as well as to express advances in building technology and to absorb new home appliances. Houses are organized in distinctive sets of spaces, arranged in form of domestic sectors (Amorim, 1997.). Traditional dwellings were arranged to reassure the unity of the family by setting spaces for interaction (the back room) and isolation (the alcoves) and turning them into a precise realm. This realm was set apart from the spaces solely dedicated to the formal entertainment of guests and the ones for the preparation of food, storage of goods, general services and accommodation of servants. These realms constitute the three main sectors of the pre-modern houses: the visitors, the family, and the service sectors. The visitors sector group’s foyer, entrance hall, waiting room, visitor’s room, reception room, library, music room, and formal dining. The service sector groups spaces primarily occupied by servants, like kitchen, laundry, garage, and backyard and servants quarters. The family sector groups the daily living spaces - dining room, veranda, family room, bathroom, bedrooms, and peripheral spaces, as closet, and toilet. Modern houses, on the other hand, are organized differently, as social and family structure has changed. Modern sectors are the following: the social sector grouped the spaces that generated the interface among the inhabitants and visitors - living, receiving and dining areas; the private sector: provided isolation for the members of the family - bedrooms and study room; the service sector housed the activities that maintained the dwellings life – kitchen and servants accommodation. In traditional rural houses of Bangladesh houses are organized around multiple courtyards. Open courts are used for most of the daytime activities of the home, segregated for use by female members of the family. The kitchen and toilets are well segregated from the living areas. This form of rural houses has seen very little change through time. In the first instances of globalization – when influences from the west in the form of Islam entered, a change came about in the religious beliefs. But social customs and general culture of the area blended with new customs and merged with the new religion, modifying rather than totally displacing old values. Socio-political changes with the advent of colonial British rule brought about changes in the region, which spurred on a spate of urbanization. Dhaka, the city which had first been established by the Mughals, began to grow. People who migrated to the city from rural areas in search of work in general were adventurous young people in search of new experiences and wealth. The increase in the importance of the status of Dhaka, first as a provincial capital after the partition of India, and then as a national capital in 1971 with the formation of Bangladesh, brought about increasing urban migration, increasing the mix of cultures, modernization and potential globalization. The jump of percent of urbanized population of Dhaka according to statistics is from 14.79% in the 1961 census to 53.94% in the 1991 census, when the city had enormously grown in stature as the capital of independent Bangladesh (BBS, 2001). Introduction of TV to the region in 1965 brought about instant exposure to culture beyond the immediate horizon. The result has been felt through history in three separate breaks with tradition – the emergence



of the nuclear family from the joint family of the past, spatial and temporal compartmentalization of areas into residential, commercial, recreational etc and this has infiltrated into the plan of residences, manifesting into spaces for different activities like sleeping, dining, studying etc, instead of the single space accommodating most activities (Imamauddin, 1982). Moreover with increased education came yet more exposure, as affluence and the possibility of travel grew. With affluence, international trade allowed the global market to enter even the most remote locality. The telephone increased the sense of closeness and simultaneity. Architecture reflects this slow influx of globalization. Replacing older values s slow transformation of new ideas and customs is seen in the residences due to necessity in some cases, and to choice in others. It is with globalization and the new incursion of ideas that choices entered the lives of these urbanites.

EVOLUTION OF DOMESTIC SPACES

In this section the evolution of the domestic space of the middle to high income group is traced in terms of globalization influences. Discussed below is how the house form seems to evolve as a shift in local customs, influenced directly from extraneous influences – an effect of globalization, rather than pure modernization. Phase 01 – dwellings during the urban beginnings In early days of 17th and 18th century, the urban house form was no different from its rural counterpart, except when forced upon by densification (Khan, 1982). From the idyllic sprawling low density settlement of rural habitats, the urban house at the beginning had of necessity to be accommodated in more cramped surroundings. Initially houses tended to retain the court, which became increasingly closed as space constraints became acute.

Fig 01: Three court house. Source: F.A. Haque, 1997 In early houses the kitchen and toilets were kept as far away as possible from the main living quarters, in a way similar to rural dwellings. A separate service court in three-court houses can still be found in these early residences (Fig 01). The first court served as a semi public court, mainly the entry court to the ander mahal (inner sanctum). Ander mahal occupied by female members of the household. On the outer side of first court was the male zone. The second court was the most private area of the household, segregated from public access. Only family males were allowed there. Female guests were also entertained through this area. The third court which is the service court In early houses the kitchen and toilets were kept as far away as possible from the main living



quarters, in a way similar to rural dwellings. A separate service court in three-court houses can still be found in these early residences (Fig 01). The first court served as a semi public court, mainly the entry court to the ander mahal (inner sanctum). Ander mahal occupied by female members of the household. On the outer side of first court was the male zone. The second court was the most private area of the household, segregated from public access. Only family males were allowed there. Female guests were also entertained through this area. The third court which is the service court where privacy was less restricted as non family males needed to enter this area for servicing toilets and for other general household activities. The servant’s quarters, kitchens and toilets were housed around this court (Fig 2). The introduction of new technology like flushing systems allowed toilets to be attached to living quarters. The introduction of cooking gas instead of fire wood allowed the kitchens to be brought closer also, as fumes/smoke diminished. In general the concept of privacy of the individual members of the family from each other was not very prevalent in either rural or early urban living. Bedrooms were often entered through other bedrooms, and windows to bedrooms opened freely onto the courts. The court disappeared generally as soon as land became expensive and density of residential areas began to increase.

Fig 2. A) Ground floor plan. B) Second floor plan. C) View of main internal family court. D) Articulation of zones



Phase 02 – mid twentieth century phase The emergence of the urban middle class in Dhaka is judged to be a 20th century phenomenon, a direct consequence of colonial rule (Imamuddin, 1982) and spurred on by a growth of Government jobs in the Civil, Military, Police, Railway and allied services. Studies shows that in the 1950s a new group of buildings emerged to accommodate this group – colonies for the Government employees (Khan, 1982) in addition cities also experienced the growth of professionals like doctors, engineers and advocates (Imamuddin, 1982). To cope with increasing demand for housing, the Government also started allotting land at relatively low prices in planned residential areas e.g. Dhanmondi R/A (Nilufar, 1997). The plots to start off were large (approximately 1/3 acre each), and the economic and social background of the allottees had a semblance of homogeneity. During the late 50s and early 60’s these areas grew populated, with a family to each plot. Houses were relatively large, normally two storied with a number of bedrooms, each with an attached toilet. The living room (or drawing room as it was popularly termed) was normally segregated from the rest of the more private areas of the house, having its separate entry. The entry to the rest of the house was separate and corridors were extensively used to connect the different spaces. Gardens all around the house served to provide outdoor space for aesthetics/recreation in the front, with vegetable patches at the back and sides. High boundary walls around the plots served to protect the plot holders. Servant’s quarters were normally provided at the back and the kitchen could be entered through backdoors. Phase 03 – post independent phase A big change came by the end of the 70’s, when the next generation needed expanded. Discussed here is the case of Dhanmondi, as representing the pattern of urban land ownership, these plots were sub divided among the inheritors into separate plots served by internal private access roads (Akbar, 2006). This trend saw the end of the joint family of the past, though the separate families tended to live in the same plot but under different buildings. During this period many rentable walk-up apartments (usually restricted to four storeys) were constructed. As soon as the single unit house was sacrificed for economic reason, life style saw a new shift. With the grounds no longer under the sole control of one householder, people needed a different space for family gatherings, thus the family living space entrenched in these urban homes. As in previous eras, no longer were corridors used as main connecting paths to individual rooms. This family living space provided the counterpart to the open court of the rural which also opened to the individual rooms and provided a space where

Fig 03: No segregation at entry, Prioprangon,

U.K.Saha. Source: Sthapattya o nirman



the family could spend much of the free time in the evenings, gossiping or watching TV. Privacy was gaining importance in family living as each family separated from the parent one. During this period, it was still common for the children’s bedroom to be located adjacent to the master bedroom, allowing the mother to monitor growing children. Phase 04 – developer built housing phase But with the ever increasing population making more demands for housing, and the prices of land rising abruptly. Much of the early housing stock was demolished in favor of apartment complexes. Commonly referred to as high rise apartments, these are normally developer designed and built and in many of the restricted to six storey’s. They are equipped with lifts and controlled by a management society, particularly to do with the use of common facilities and spaces. Community living has brought another change in the lifestyle of the urban dweller. Open spaces are meager due to dearth of land, and any that can be provided in such complexes are no longer private areas. The urbanite now shares these spaces with people they have only recently seen and may not yet have been acquainted with.

Fig 04: Evolution of the dwelling: schematic phases. Source: (Ahmed, 2009)



THE CHANGING FACTORS

In this section discussed the major factors of the changing trend like living cost, change in living style, family size, influence of housing society and most importantly influence of technological changes. Cost of Living: The cities of the developing countries have always been faced with the growing gap between the earning and the expense of the middle class urban working level families. The growing land price and the affordability of space are dividing the land into much smaller parts and the choice of living space is very limited to the high value. A major share of the average family expenses is to afford the cost of living space, be it in terms of rental or mortgage. With the growing inflation rate almost close 7.93 % for August 2012 as per Bangladesh Bureau of Statistics, family earning growth is very limited. The pie chart of the household expense is limited to the same earning number with a major shift in the expense share of the pie to cost of living every year. The high expense is forcing families to accommodate in less space, thus adding to the demand for smaller size urban residential units. Changing Life Style: Present day urban family size is becoming very limited to the its size and life style, with an average single family counting to husband, wife and two children, the traditional join family concept is fading its way of the urban scenario. With more working parents and opportunity of urban activities, one might term this as a western influence or modern culture, but the facts remain for the growing cities culture and life style changes with the changing factors of globalization. The influence of international work place practices infill within the living spaces and is a combination of private and public life that redefines the urban life style. Daily living practices starts to define the need of space and the functional aspects of the living spaces. Play fields of urban communities are redefined in individual apartments with play station and game room. Public libraries have turned to windows of information resources with a laptop demanding now additional space. The interior space have adapted to multiple functions and changing spatial space with the change of activities, a screen in the house is at one time an entertainment center, a study resource and a games hub of fun as and when the activity defines the function of the space. This changes of life style has taken away the need of individual spaces and infused a more open space adaption to the growing demand of urban living spaces. Small Family Size: With the growth of urbanization and cost of living, the share of expense has forced families to step out of the tradition and culture of combine family spaces. Responding to the changes in more open society, the concept of joint family house of multiple generation and siblings is taken on new form of multiple urban units with occasional coming together of families to celebrate major events. With smaller families and less private space need, the smaller urban apartment units are making its ways into the housing market. This demand is higher within the families with working professional parents wanted to be part of urban apartment society with shared communal spaces and having a sense of security.



Fig 05: Plan with separate entries, Niraloy.

Source: Z.N. Ahmed

Fig 06: Plan with double entries, Source:

Developer Housing Brochure

Neighborhood Community to housing Society: The high demand of land and smaller family size has given way to the urban residential areas to go from neighborhood community to the concept of small housing society. These housing societies are a concept outfall to share the limited land parcel to build multiple dwelling units building under the corporative cooperation system. This in turn forms a society to jointly take the ownership of the land and the building facility. The transition from family house to apartment society has made its way to the adaption of urban land value and adding smaller units to one building jointly owned by a number of families. Traditional family courtyard houses have been replaced by the condominium buildings with spared amenity spaces.

Fig 05: Plan with separate entries, Niraloy.

Source: Z.N. Ahmed

Fig 06: Plan with double entries, Source:


Fig 07: Plan with one entry, Dhanshiri, B. Haque. Source: Sthapattya o nirman




Technological Space Changes: Modern day technology has again and again tried to define the space it demands, within the homes and in public spaces. The introduction of TV once changed the functional aspects of family living area of a house and with the coming of personal computer demanded space for its functional needs. As the technology changes its form and shape, so does the need of the space that caters to its function. With the present day Wi-Fi connectivity and easy hand help touch screen devises the need of defined spaces is no more applicable and the devices around the living space can easily flow within the open planning interior space of small urban units as and need of the activity. With TV on the wall, cell phone in hands and washing machines the interior spaces and be one in all and all in one.

CONCLUSION

Social and spatial structures, one abstract and the other material, are closely interrelated; however, in everyday life the experience of spatial formation is largely intrinsic. While environment modulates space, it is in turn shaped by society. Thus, society retains its basis in forming space, while space, apparently a physical entity, conserves the social structure that occupies it. Even in the urban context, these powerful social influences have guided the development of physical patterns. One direct consequence of colonial rule in Bengal during the late nineteenth and early twentieth century was the creation of urban social elite. Today urbanization in Dhaka has continued and has put tremendous pressure on limited residential land. As a result, house form has become even more consolidated, and buildings have increased in height. Nevertheless, the traditional image of living around a court continues to guide design decisions in urban areas, despite limitations caused by a lack of land, rigid road layouts and the expense of modern materials, building techniques, and services. Urban development patterns so far point more toward the transformation of the courtyard form rather than its disappearance. Even in the latest emerging morphology of multistoried flats, the court is being replaced by an internal family lounge. Every day practices are always changing, the need of space is changing, the activity relative to the central space is changing, yet the very basic idea of space hierarchy continues to redefine its space arrangements to reflect the climatic need of the building and the cultural respect to the architecture that is very much home grown. Transformation of living spaces and its changing factors from traditional houses to present developer housing have been identified through the different sections of this paper. Globalization and its impact on the society and culture, and ultimately on living spaces have been identified here. Societies are formed through cultural continuity, and are through the ages exposed to different influencing factors. The paper has focused on the transformations of urban dwellings for the middle class urban population of Dhaka representative of urban working majority. The factors discussed are influencing the space needs and it is off responsive to this need that the coming of new form of buildings are emerging to cater to the changing urban fabric. The shift in the division of the space distribution of a building is emerging to its new identity, one that is not just imported and dropped into the city but rather a careful response to the society need, economic feasibility, and environment sensitive and culturally welcomed.



REFERENCES

Ahmed, D. Z. (2009, January). Tracing Globalization: reflection of changes in lifestyle in

domestic architecture. Protibesh , 17-28.

Akbar, M. T. (2006). Aspects of Social Interaction in the Neighborhoods of Dhaka city. Bangladesh University

of Engineering and Technology(Buet). Dhaka: Unpublished M.U.R.P Thesis.

Amorim, L. (1997., April, 16-18 ). The sectors paradigm: Understanding modern functionalism

and its effects in configurating domestic space. London: Space Syntax: Proceedings of

the first international symposium.

Bangladesh, G. o. (2001). Bangladesh Bureau of Statistics (BBS).

BBS, B. B. (2001). Statistical yearbook of Bangladesh. Govt of Bangladesh.

Brolin, B. (1976.). The failure of modern architecture. New York: Van Nostrand.

Emge, A. (1992.). Old order in new space: Change of troglodytes’ life in Cappadocia. In

Traditional dwellings and settlements working paper series,. Center for environment

design research: University of California.

Imamauddin, A. H. (1982). A study on Urban Housing in the context of Dacca, Bangladesh. Katholic

University of Leuven, Belgium: Unpublished ME in Arch Thesis.

Imamuddin, A. (1982). A study on Urban housing in the context of Dacca, Bangladesh. Katholic

University of Leuven, Belgium: Unpublished ME in Arch Thesis.

Kalia, R. (1987). Chandigarh: In search of an identity. Carbondale: Southern Illinois University Press.

Khan, I. M. (1982). Alternative approach to the redevelopment of Old Dacca. Katholic University.

Leuven: Unpublished doctorate disertation.

Lang, J. (1987.). Creating architectural theory: The role of the behavioral sciences in environmental

design. New York: Van Nostrand Reinhold Company.

Nilufar, F. (1997). The Spatial & Social Structuring of Local Areas in Dhaka City - A Morphological Study of

the Urban Grid with Reference to Neighborhood Character within Naturally grown Areas.

University of London: Unpublished Doctoral Disertation, UCL.

Potash, B. (1985. ). Western architecture and African urban environments. Environment change-

Social change:. The proceedings of the sixteenth annual conference. New York City.

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Transformation of Dhanmondi Residential Area-

Causes, Effects and Proposal to Rejuvenate

Sonya Afrin1, Ishrat Zerin

2, Subarna Sharmin

3, & Kazi Murshida Morshed

4

1Assistant Professor, Department of Architecture, Stamford University Bangladesh 2Lecturer, Department of Architecture, Stamford University Bangladesh 3Design Engineer, RIIP II, LGED 4Architect

ABSTRACT

Dhanmondi is one of the high-class residential areas of Dhaka City. The area was planned and developed in the early fifties with large plots, wide roads and good environment. The main objective of the study is to make an investigation into the transformation of the this area with respect to land use, building height, intensity of land utilization (building coverage and FAR values), land-sub division and also the causes of the changes. From the study it is found that the non-residential uses are about 50% of the total; more than one fifth (21%) of the original one or two storey building in Dhanmondi had been rebuilt to six storey apartment structures; the intensity of land utilization, in terms of building coverage increased from 28.3% in 1962 to 50% in the year 2000; and the intensity of land utilization, in terms of FAR value increased from 0.39 in 1962 to 1.68 in the year 2000. Present expansion of Dhaka City, more than six times bigger than the Dhaka of the fifties, created demand for new spaces for new urban activities, and Dhanmondi gained location to the central part of the city. Transformation of the area is towards more intensive use of land; multi-storied apartments and non-residential uses. The non-residential uses have taken place uncontrolled, unregulated and haphazard manner to the detriment of the residential environment. Hence a revised plan of Dhanmondi has been urgent in order to control and regulate undesirable development in Dhanmondi for which a brief proposal is included in the study. Key words: Transformation, Residential area, Non residential area, Apartment buildings, Land use.

1. INTRODUCTION

Dhanmondi settlement had its origin in a periodic paddy (Dhan) market (Mondi) in the locality in the early 17th century. The presence of numerous ponds, an Eidgah (place for biannual religious congregation), and a number of Mosques dating from the early 17th century are indicators of a flourishing settlement here. The settlement declined with the fall of the Mughal Empire. To meet the housing demand of the rapidly expanding city, after



Dhaka was made headquarters for the provincial government of east Bengal in 1947, a new area of better housing was developed at Dhanmondi in early fifties, on a land measuring 472.64 acres.

1.1 Backdrop of study

Dhanmondi residential area, designated as Ward no. 49, is located at 23.7389° N 90.3847° E in the Dhaka District of Bangladesh. It has 33451 houses and a total area of 9.74 km² (BBS, 2006).

Fig 1.1: Dhaka Guide Map Fig 1.2: Blow Up of Dhanmondi Residential Area (Northern part) [Source: DMDP]

The Construction and Building Department of the government of East Pakistan acquired about 500 acres of agricultural and horticultural lands in 1950, leveled it and divided the land into plots and finally allocated the plots to ministers, government officials, public leaders, professionals, and businessmen. DIT later undertook the task of creating public facilities and roads and other facilities. The area was divided into blocks, which were in turn sub-divided into 1083 individual rectangular plots, measuring approximately a bigha (0.33 acres) each. The plots were laid in a grid iron pattern having roads 150’, 45’, or 30’ wide, organized around an existing water channel, dug out and latter extended to form an irregular shaped lake having 2 storey buildings with front green lawn. The plots were leased out to allottees for 99 years at a payment of Tk 5,000 per bigha.

Initially, DIT (Rajuk from 1987) kept Dhanmondi plots exclusively residential and did not allow use of any plot or house for commercial purposes. But in response to tremendous pressure on city land after 1972, the rule was relaxed to the point of virtual non-application. In 1995 DMDP approved Dhanmondi as a mixed use zone but placed certain strict limits in

http://toolserver.org/~magnus/geo/geohack.php?pagename=Dhanmondi_Thana&params=23.7389_N_90.3847_E_

http://en.wikipedia.org/wiki/Dhaka_District

http://en.wikipedia.org/wiki/Bangladesh

http://en.wikipedia.org/wiki/Area

http://www.bbs.gov.bd/

http://www.worldlingo.com/ma/enwiki/en/2006



the types and account of commerce that would be permitted, that is, only commercial services that were immediately related to meet the residents’ daily and weekly needs.

Consequently, now almost 50% or more plots are used for commercial purpose, which include shops and stores, government and semi-government offices, show rooms and warehouses of business firms, NGO offices and clinics, educational institutions and even manufacturing units and maximum of the rest plots already having 6 storey buildings, and accommodating 20 families per bigha rather than recommended 1 family. This increasing number of commercial establishments, coupled with the lack of adequate parking facilities, has given rise to a tremendous amount of traffic congestion, especially during the mornings and afternoons when children are dropped off and picked up from school, and during the evenings when shoppers from all over Dhaka throng the various shopping centers. Socially and economically, Dhanmondi has now become a multi-purpose area (Shafi, 2005).

1.2 Objectives of the study

It has become necessary to understand the existing movement of transformation pattern of Dhanmondi residential area, so that effective measures can be taken to control and protect the area from invasion of further unplanned development. Hence, the paper has been prepared with the following objectives:

a) To study the spatial variation of the existing transformation of the area.

b) To identify the changes in the development pattern of the area.

c) To study the perception of the user regarding the changes.

d) To formulate policy guidelines and a brief proposal for future development of the area.

1.3 Methodology of the study

The Methodology followed for the study is comprehensive and intensive. The steps followed are stated below:

1.3.1 Literature survey An elaborate literature survey on the topic was carried out for better understanding and representation of the problem. 1.3.2 Collection of data from primary sources Preliminary Survey: A preliminary survey was conducted to gain a general impression of the area so that the subsequent operations of land use surveys could be successfully carried out. Detail Survey on Development Pattern: A detail survey on existing development pattern was carried out over the whole area of Dhanmondi. 100% of the plots of the area were surveyed. The survey contained the following aspects:

Types of land uses

Plot subdivision / land fragmentation

Height of buildings

Vehicular load on the existing road About 5% of the plots were surveyed to study the intensity of land uses in terms of building coverage and total floor spaces within the plot areas. 1.3.3 Collection of data from secondary source Due to the nature of the topic, part of the study was based on published references, studies and office works of both Government and semi—Government offices for availability of materials. Detail Land Use surveys of three organizations was collected:



Land Use Survey of housing and Building Research Institute in 1984

Survey of non-residential uses by Public Works Department in 1999

Detailed Area Plan by RAJUK in 2008

Dhaka Metropolitan Development Policy [DMDP] 1.3.4 Analysis of the collected data The collected data was edited and tabulated manually using simple statistical process. The descriptive and unstructured materials, observation, surveys, documents and other records were summarized and arranged in a sequential order. The layout map of Dhanmondi Residential Area was used as the base map to show the spatial variation of land uses, height of buildings, and intensity of land use and land sub-divisions. After fact-finding policy guidelines were formulated for effective spatial pattern of development in Dhanmondi Residential Area.

Fig 02: Map of Dhanmondi Residential Area (Morshed, 2008)

http://banglapedia.org/Maps/MD_0186.GIF



1.4 Meaning of transformations

Over the years, transformations in urban areas have taken place in varied forms, including those pertaining to size of form, land use, encroachments, structure heights, floor area coverage in other words illegal constructions etc. This has also occurred in the formal developments of the city very much outside the legal framework. However, the growth may not be in accordance with the planning norms of the city, but its very existence highlights its magnitude. Some of the key transformations occurring in urban areas in general and Dhanmondi in particular are summarize in subsequent paragraphs. 1.4.1 Use affiliation

This is a type of transformation that pertains to extent and enhances non-residential use in residential areas and of other uses in areas meant for open spaces. This phenomenon is very evident along the main transport routes and in the developments with smaller plot sizes/ dwelling units. In other words, it can be stated as invasion of stronger land use over weaker in terms of prevailing demand, which is acting as an impetus for growth of a particular land use. For example at several places in Dhanmondi, the residential buildings along the road or streets near a planned market or business areas are converted to commercial spaces, open areas are being encroached upon for houses, shops etc. The prime reason of this type of transformation is pressure exerted by economic forces, where in the importance of economics prevails over that of habitation. 1.4.2 Built form

The transformation is in terms of extent of consolidation, horizontal coverage, encroachments, condition of structures, streetscapes. To fulfill their need of habitable space people tend to increase the covered area of the plot. There are encroachments on the common open spaces or the road to accommodate their needs. The dwelling units are converted to commercial uses for retail shops etc. and the residential activities are accommodated on the additional floor which contributed to the height transformation occurring in the planned developments. This type of informality is seen in formal settlements having very small areas of dwelling units which with passing time becomes difficult to manage with. Social pressure is the main reasons for this type of transformation where an increasing population, needs to be accommodated in the limited planned space. 1.4.3 Time affiliation

This type of transformation pertains to the changes that happen over a period of time. In terms of time relationship, the informal growth may be of temporary nature (which have become permanent over time), permanent nature or appearing before its envisaged time. For example, increasing area use by periodic markets, roadside petty sales, gets converted into permanent markets etc. The permanent nature of informality refers to the developments fully or partly, those covered under land use or ownership related informality. Social and economic issues both are involved in pushing such type of transformations.

2. STUDY AREA APPRAISAL

2.1 Planning aspects of the project: Dhanmondi residential area

Dhanmondi Residential Area was planned as sites and services scheme with a regular system of roads to provide residential accommodation. Dhanmondi Thana (dhaka district) with an area of 7.74 sq km, is bounded by Tejgaon and Mohammadpur Thanas on the north, Lalbagh thana on the south, Ramna Thana on the east, Hazaribagh and Mohammadpur Thanas on the west. Administrative Dhanmondi Thana was established in 1976. It consists of three wards, 20 mouzas. 2.1.1 Land acquisition and plotting



By the order Dhaka No.11413 rcqu.-9th December 1952 whereas by order, dated the 25th February 1949/16th September under section 3 of the East Bengal (Emergency) Requisition of property Act. 1948 (E.13.Act XIII of 1948), seven mauza (some fully and some partially) were acquired, which are given in the following table: Table 2.1: Land Acquisition

[Source: Alam, et al, 1986]

Total area of the project was divided into 1,000 nos. of plots originally ranging from 15 decimal to 33 decimal (Alam, et al, 1986). But in the layout plan, found in the present Public Works Department the total number of plot is 1083 (PWD, 1958). Allotment price was Tk. 15,000/- per 33 decimal (locally called Bigha) and there was provision of paying the price in four installments with low rate of interest. The annual rent of the land was fixed to tk. 36/- per Bigha per annum and payable from the 5th year of the allotment. (Alam, et al, 1986) 2.1.2 Road pattern Dhanmondi has a grid pattern of roads and almost all the plots are rectangular and of the same size (14,400 sft). Three types of roads were designed for the area i.e. Major thoroughfare (Mirpur Road and Satmasjid Road) of more than 30 meter width, Secondary roads of 15 meter width and Access roads of 10-15 meter width. In case of secondary and access roads one third of their total width were medaled and have provision of footpath on both the sides.

Fig 3.1: Road Network of Dhanmondi Fig 3.2: CAD Drawing of Dhanmondi Road Network [Source: Dhaka City Corporation] [Zerin and Rahman, 2007]

Mauza J.L.No. Acquired C.S.Plot Nos.

Fully Partially

Dhanmondi 251 166 29

Taleperbag 253 22 x

ldgah 252 84 x

Shukrabad 260 180 30

Shibpur 254 81 25

Sarai Jafrabad 257 43 14

Sarai Begumpur 258 X 2



2.1.3 Land use Of the total area, more than 61.4 % land was proposed for housing purpose, 9.2% for open space, 9.2% for water bodies and more than 18% for internal road circulation. Open space included the water bodies, play ground children’s parks; etc totaled to about 18.4%. Dhanmondi has an edificial lake. Besides these areas, there is 4.7 acres of private land (Sobahan Bagh), which is situated within the Dhanmondi Residential Area. An existing khal (water channel) has been dug and extended to form an irregular shaped lake. This is the only break in the monotonous layout of the Dhanmondi Area. (Islam, 1996, p.24.) Table 2.1.3.1: Land Use of Dhanmondi Residential Area

Land Use Area (in acre) Area (in %)

Total residential area (plot) 298.3 61.4

Roads 89.6 18.4

Water body 44.6 9.2

Park and play ground 44.7 9.2

Mosque 4.7 0.9

School (public and provided in the original plan) 4.4 0.9

Total area 485.9 100

[Source: Public Works Department, 1958.] Dhanmondi Residential Area did not have any neighborhood shopping centre, corner store, park, community centre, club, etc. The whole area was divided into plots without keeping in mind the facilities that a community requires (Islam, 1996).

Fig: 4: Bar Chart of Existing Land Use of Dhanmondi [Zerin and Rahman, 2007]

If we take a closer look at changes along the road side development of four major road fronts of Dhanmondi we find the following growth of commercial and institutional buildings in the past three years shown in the table below:

0

100

200

300

400

500

600

700

800

900

1000

1100

1200

NUMBER

RESIDENCE

COMMERCE

MIXED USE

HEALTH FACILITIES

COMMUNITY FACILITIES

EDUCATIONAL INSTITUTE

RECREATIONAL SPACES

CULTURAL ACTIVITIES



Table 2.1.3.2: Built Structures of Dhanmondi:

[Source: SCPL Field Survey: July 2004, Shafi, 2005]

Note: The number of uses is listed in plots. The buildings listed above stand alongside the major roads on equal frontage and height and look alike despite different functions. The shopping mall/ plazas are comparatively more glamorous in their finish and are relatively more beautiful buildings designed to accommodate shops selling expensive products.

3 Transformation of Dhanmondi residential area-causes and effects

A study of the 1974 situation shows that a traditional mahalla, chawk or Neighborhood Square (Mowla, 1997: 251) pattern has began to emerge within this grid layout and subdivision of plots also began to take shape of informal developments. In due course sub-division of plots to a minimum of 8 decimal and construction up to six storied buildings with much reduced setbacks were allowed with in a maximum of ten family units per 33 decimal plot. Relaxation of use has also taken up over time, allowing educational institutions on any plot and non residential use along Satmasjid Road, Road no. 2, Road no. 16 and Mirpur Road (a major artery road) up to a depth of 6m. Spontaneous civic spaces also became apparent with the change of this use in the area, attracting a number of unplanned uses (Mowla, 2003). 3.1 Development control measures for Dhanmondi residential area

The invasion of non-residential uses within Dhanmondi Residential Area in an unplanned, uncontrolled and haphazard manner had affected adversely on the residential sanctity of the area and the area has already lost its status as a high- class residential area of Dhaka City.

Sl no. Establishment Category Nos.

1.

Educational

Institutions

Schools 44

2. Colleges 06

3. University 12

4. Other Institutions (Coaching, Computer Learning Center, etc.) 12

5.

Commercial

Establishments

Banks 15

6. Community Center 08

7. Departmental Store & Confectionary 24

8. Fast Food & Restaurants 16

9. NGO Offices 20

10. Miscellaneous Offices 66

11. Other (Business Enterprise not including in listed categories) 43

12. Shops –

13. Tailor & Boutique & Beauty Parlor 19

14.

Health Care

Clinic 31

15. Hospital 16

16. Pathological Lab 14

17. Diagnostic Center 12

18.

Games &

Sports

Abahani Club Ltd. –

19. Kalabagan Sporting Club –

20. Women’s Sporting Complex –

21. Dhanmondi Club –



The gradual degradation of residential sanctities had created a concern for the public authorities. As such some actions were taken by the Ministry of Housing and Public Works to control and regulate the developments within Dhanmondi Residential Area. The Ministry of Housing and Public Works formed some committees from time to time to investigate into various types of developments within Dhanmondi Residential Area and served circulars on the decisions of the authorities regarding development controls in this area.

Circular of May, 1995, Ministry of’ Housing and Public Works

The authority imposed the following development control “measures for Dhanmondi Residential

Area in May 1995:

Plots, adjacent to Mirpur Road may be used for commercial purpose up to 20 feet depth, with 15%

“Conversion Fee”. This rule also will be applicable for Road no. 16 (Old Road no. 27), Road no. 2

and “Satmasjid Road”. No uses except those mentioned below, will be permitted:

a. Books, Papers, Stationary and Medicine shops

b. Goldsmith, Watch and Spectacles shops

c. Antiques and Curio

d. Travel Agencies

e. Bank and Insurance

f. Show Room of Car and Filling Station

g. Office of Commercial Institution (with the permission of the Authority.)

h. Snacks Bar (not Hotel and Restaurant and Posh Restaurant)

i. Photo Studio

j. Show Room: Ceramic (with the permission of the Authority)

k. Electronics equipment.

1. Clinic: up to 10 beds (but not of Infectious disease)

m. Commercial uses for the requirements of the local community and that are socially acceptable

may be considered to get permission.

n. Small shops for daily necessities may be considered to get permission with the condition that:

• Shops will have parking arrangement.

• The shops will face the road.

• The shops will maintain distance from footpath according to the rules.

• The plots allotted for residential use will apply to the authority and the buildings can be made

usable for commercial purpose.

Circular of January, 1996, Ministry of Housing and Public Works

The authority legalized all the plots, on both sides of Mirpur road, Satmasjid road, Road-2 and

Road-16(old 27) for commercial use with 15% “Conversion Fee”. By the circular the total plot (not

partial) was permitted to be used for commercial purpose.

This permission was considered to be effective from December 1995. It is interesting to

note that as per original plan no one was supposed to built structures more than three

storied (Alam, et al, 1986).

But then the authority withdrew the ceiling of dwelling density of: 10 flats per bigha (33

decimal). According to this circular:

The maximum permissible number of storey in the buildings will be six but the number of flats

may be as much as is possible to be served by the service organizations.

The building shall have lift facilities and parking arrangement within the plot area.



The size of a subdivided plot shall not be less than 5 katha.

This circular was considered to be effective from December 1995.

In order to a specify guideline for use of land, plot subdivision, construction of apartment,

transfer of’ title, height of building for Dhanmondi Residential Area a committee of 16

members was formed in June 1995, known as ‚The Zahir Uddin Committee‛ (June, 1995,

Ministry of Housing and Public Works).

The committee decided that:

a. Present rule of building height of maximum 6 storeys in Dhanmondi Residential Area would

continue.

b. The service giving organizations would assess the problems providing services to increased

height of building and will recommend to the ministry whether the heights of the buildings could be

increased further. These organizations will assess the problems and their solutions at interval of 2.5

and 10 years. After receiving the opinions, of the service giving organizations the Ministry would

call another meeting to take decision in this regard as soon as possible.

But up till year 2000 there was no new decision to increase building height.

From the above discussions it is evident that the public authorities are keenly interested to

retain the residential character and to regulate and control nonresidential development

within Dhanmondi Residential Area. The public authorities are also interested to increase

the intensity of land utilization by increasing the height of the buildings without bringing

any adverse effect on the environmental conditions, especially on the utilities and service

facilities.

3.2 Detailed area plan by Rajuk

Following strong regulatory framework should be prepared for DRA. It is desired not to

have any more residential development as density has already crossed 300ppa. It is

assumed from a reliable source that the area has now more than 1.50 lakh people.

Removal of offices, hospitals, clinics and schools through formation of legal

frameworks from authority is required except the designated commercial Avenues or

roads.

Some roads should be converted into one way road. Using of Dhanmondi roads

vehicular traffic from other neighboring areas is discouraged through constructing

gates in appropriate places of entry and exit.

More extensive use of Satmasjid Road has been proposed through opening of BDR

Road for public use and linking the Satmasjid Road up to New Market through the

road inside BDR.

New construction as well as re-development of buildings within this area must follow

the existing building construct ion rules. More over, height limitation seems essential

to apply up to 6 storeys to keep the density with in a reasonable range.

Through guided land development, Kalabagan triangle may be developed.

Messages of Environmental Upkeep campaign should be disseminated to the DRA

residents explaining the need for maintaining residential serenity and therefore their

share of responsibility into this preferably by Dhanmondi Poribesh Unnayan Jote and

other civil bodies.



Convert some roads which are mostly in use into one way for traffic. Stop using

Dhanmondi Road as for vehicular traffic for other neighboring area. As for rest of the

Roads, the entry points from Mirpur Road and from Satmasjid Road should be

regulated with gates.

Huge rickshaw traffic from neighboring Lalmatia and Mohammadpur are regular

user of DRA roads in order to go to New Market, Nilkhet, Azimpur and University

area. Alternative steps should be taken for this traffic, i.e. open up the road within the

BDR for public use with separate rickshaw lane along Satmasjid Road. Also

recommended widening 80 feet road along Shrai Zafrabad Road, Sher-e-bangla Road

through Hazaribagh Road connecting New Market.

DRA seriously lacks civic amenities like clubs for women and elderly people, library

for the children and women, cultural museum /Hall, modern Art gallery, drawing and

painting school, car and rickshaws parking lot, small parks, post off ice either in

Mirpur Road or at Road no.-27. All the abandoned properties within DRA should be

used to provide these facilities. Private land owners may be encouraged but in that

case land need to identified. The park at road no. 4 should clearly be earmarked for

women, children and elderly people; the present use of road no. 4 Park as cricket

ground should immediately be stopped.

The entire DRA should be divided into small neighborhood and neighborhood

association should be created and made mandatory to preserve their area’s

environment security and other interest.

Presently. DRA lake is a center for drug abusers/peddlers, hooligans, hijackers and for

anti social activities. So, for DRA lake development, all the lake centered business and

commercial activities, loitering of teenagers, selling cooked foods, should be stopped

and only garden should be created with enough plantation and bird nests be created

and accumulated in the Dhanmondi R. A. There should be a fixed time w hen general

people w ill use lake premises. For further expansion and development of lake for

future will require a careful study and planning, for example, redevelopment of

Begunbari khal and its renovation into a park of amusement/ recreational centre is

highly recommended, so pressure on Dhanmondi lake get reduced.

The entire Lake area should be filled with gardens, plants, shrubs.

All the pavements and roadside plantation should be encouraged to bring back the

greenery effects of the area (Ministry of Housing and Public Works, 2008).

3.3 Causes of non-residential use at Dhanmondi

Dhaka city has a current growth rate of 6.5 percent and contains almost 30 percent of the

total urban population of the country. By 2015, it is predicted that Dhaka’s population will

be 23 million and it will be the world’s fourth largest city. This rapid change in land use

and the use of buildings etc. without reference to any planning or assigned function are

destroying the characteristics of planned areas in the city. The reason for this is not only

lack of planning and control but also investments of accrued wealth in the construction of

new buildings for all types of uses i.e. residential, commercial, institutional etc. A recent

study on tall buildings on Dhaka city reveals that there are more than 550 tall buildings in

Dhaka city, which have been constructed in the last 20 years bringing about changes in the



land use and general environment of the city. Also an invasion by commercial type of

building seems to be taken over most of the planned residential areas. Initially, in

Dhanmondi, the need for community facilities was totally ignored. There was only one

school and one mosque within Dhanmondi. Gradual invasion of non-residential uses has

drastically affected the quality and changed the character of Dhanmondi. At present there

are about 89 schools, colleges and universities, 88 medical centers and hospitals and about

108 offices within Dhanmondi. There are also a large number of community centers,

beauty parlors, food outlets, clubs, museums, etc. All these facilities serve not only

Dhanmondi but also the whole city of Dhaka. One can hardly find a lane in the city where

there is no office, said urban planners. They said that the Master Plan of the city of 1959

had provisions for exclusive commercial zones of Motijheel and Dilkhusa and the Tejgaon

industrial area. They also mentioned though the plan was to be completed by the late 70s,

no new Master Plan could be formulated until 1995. In absence of a Master Plan the

commercial zones expanded in all sides due to increased demand for commercial space.

Karwan Bazaar also has become a commercial zone hosting important offices and bank

branches. Recently, Agargaon is turning into another commercial zone. Some of the

residential areas are hosting private sector educational institutions and the offices of

telecommunication as well as multinational companies. Kindergarten schools, colleges and

universities proliferate Dhanmondi Residential Area ( Shafi, 2005).

3.4 Effects

The evolutionary trend of DRA from 1952 to 1996 suggests that this once exclusive area for

better residence is gradually being transformed to a traditional mixed use zone or in

panning terms ‘an out lying business district’ (Mowla, 2003).

3.4.1 Plot sub-division

Most of the present plot owners of Dhanmondi area the second or third generation of

original owners. In most cases number of successors arc more than one. About one-fifth of

the total plots are now physically subdivided. The present law of plot subdivision does not

allow physically subdivided plots to be smaller than five kathas. In this situation the

successors having title of land smaller than five kathas have common ownership over the

plot. They cannot sell or mortgage individually, every action have to be made through

group approach. This creates sonic operational problems while selling or redeveloping the

plot. On the other hand, owners of the flat housing (apartments) are free to have their title

on the plot individually. Ownership of their subdivision would he undivided and not

demarcated over the land. But they may sell or mortgage their title over the land

individually. They would not have to take group initiative. This law of land subdivisions

induces apartment housing to be a solution to get rid from the complicated situation of

tenancy in common. Moreover the present owners (successors of the original owner), who

are economically obsolete finds agreement with the developers to be an easy solution for

redevelopment.

All the above mentioned situations result and would result one common type of

developments in Dhanmondi, i.e. Multi-storied apartment. About one fifth of the original

plots are now physically subdivided. These subdivisions are due to transfer by selling of

land or due to multiple numbers of successors. Increase in the number of subdivisions



increases the intensity of built structure. In the original layout collected from the Public

Works Department, there were 1083 residential plots. Some of the plots were subdivided

by the owners themselves later on in 1984 it was 1131 (Alam et al, 1986). The present study

found the existing number of plots to he 1382 (Field survey, 2000).

3.4.2 Intensity of vehicular movements

Three types of streets (30meter, 15 meter and 10-15 meter), having sidewalks, are provided

in Dhanmondi. Traffic system of Dhanmondi, though a planned area, collapsed due to the

presence of too many educational institutions, medical clinics and hospitals. A number of

roads in Dhanmondi are also being made one-way from 7:00am to 8:00am to reduce traffic.

3.5 Impacts of transformation

Good access and favorable size of plots in Dhanmondi proposed the conversion of plots

and even individual apartments to commercial services for all of Dhaka city’s population.

The result is that residents of Dhanmondi area have to suffer from huge influx of from

outside resulting in severe traffic congestion, air and noise pollution and solid waste

management problem (Shafi, 2005).

The over-concentration of schools, medical facilities and business establishments has

extremely negative social consequences. Every work day of the week, these commercial

operations draw in thousands of parents, drivers, and rickshaw pullers and inevitably, the

vendors that caters to them. The result is further loss of environmental quality and

deepening social chaos.

3.6 Proposal

Dhanmondi residential area must be protected from invasion of unplanned development.

This ward can be planned as a small self dependent township. Local area planning and

improvement of governance will prevent a lot of irregular land use and building

construction, reduce traffic congestion and allow for planned development. It is expected

that if and when involved in planning of the area, people of all neighborhoods will not

allow access of shopping plazas, hospitals and clinics within their locality. On the

contrary, they are likely to insist on meeting mainly on population requirements of that

area. Control of residential density is also a factor that needs to be carefully considered

when planning for a residential area like Dhanmondi. Whenever residential densification

in any area is allowed it should be done in a manner so that there is adequate open space

on the ground in ratio to the increase of families per plot. This can be achieved by allowing

apartment buildings in residential areas to build as a complex of buildings and not single

buildings. To fulfill the need for land for civic amenities/ institutional/ commercial

purposes in any area of increased a local/ detail area plan will find such spaces through

application of land development techniques such as land sharing, land readjustments, etc.

For example if Dhanmondi area requires further land for ancillary uses such as school,

colleges, health, markets and definitely open space, investors and developers can be

provided land through land sharing techniques and also urban redevelopment processes.

These are complex procedures and need professional input as well as peoples’

participation.



3.6.1 Existing map of Dhanmondi

Fig.4.1: Dhaka Guide Map (Northern Part) Fig 4.2: Google Image of Existing Situation of

[Source: DMDP] Dhanmondi Residential Area [Source: Google Earth]

3.6.2 Considerations taken into account for preparation of the proposal

A green square and sometimes a memorable street for a transition stop would be

located in the area.

There should be a variety of dwelling types so that younger and older people, families

and singles, the poor and the wealthy besides other cross section of people may find

places to live.

There should be shops and offices at the edge of the neighborhoods, of sufficiently

varied types to supply the weekly needs of a household and make the area lively

around the clock.

Elementary school should be close so that most children can walk from their home.

There should be small playgrounds near every dwelling, not more than a tenth of a

mile away.

Streets within the neighborhood should be a connected network, which disperses

traffic by providing a variety of pedestrian and vehicular routes to any destination.

Parking lots and garage doors should rarely front the street.

Buildings in the neighborhood centre are closed to the street creating a well defined

outdoor or urban lobby.



3.6.3 Proposal plan of Dhanmondi

Mosque

Education

al zone

Education

al zone

Hospital

Play field

Mixed-

use

Mixed-

use

Play field

Play field

Nursery

Mosque

School

School

Nursery

Universit

y

Mosque

School

Mixed-

use

Mosque

Mixed-

use

25 storied

bldg. 12/15 storied

bldg. 12/15 storied bldg.

12/15 storied bldg.

12/15 storied

bldg. 6 storied

bldg.

Paved area

Open green space

Lake

Lake



4 DISCUSSION AND CONCLUSION

The study reveals two important trends of transformation in Dhanmondi -growth of non-residential use and the construction of six-storied apartment buildings. From the study it is also evident that the public authorities are very keenly interested to retain the residential status of Dhanmondi, and from that end, planning authorities imposed some regulatory measures and control on the non-residential uses in Dhanmondi. The recent trend of construction of six storied apartment buildings from 1990 onward is the result of relaxation on the height restrictions of the buildings. Previously the buildings in Dhanmondi were not allowed to be constructed more than four storeys. The decision to impose height restriction up to six storeys is the outcome from the consideration of two important utility services i.e. the water supply and electricity. Every planning decision is required to be based on certain facts regarding projection of population in the future, ultimate population growth, calculation of requirements of utility services and community facilities, traffic generation and transportation network, assessment of provision standards, etc. For imposition of height restrictions in Dhanmondi all these facts have not been assessed properly.

For example, with the construction of six storied buildings in Dhanmondi, what will be the intensity of development in terms of FAR value, what will be the occupancy rate and population density, what will be the ultimate population load in the area, what will be the standards and requirements of utility services and community facilities like schools playgrounds markets, shopping centers.

In any event, the whole process of planning and replanting an existing area is to give it a character of its own and to guard against possible deterioration. It is to be remembered that planning should be done for the people, not for the planner, and is the creation of physical pattern so designed that personal, family, social, and economic life can flourish within it. To bring about a satisfactory solution of the problems it requires a new collective conscience within the planning profession and a comprehensive view of urban society and its social, spatial and environmental relationships. Community based organizations and local community participation can play a great role in safeguarding and protecting the environmental qualities of residential areas. Hence, there should be scope for effective community participation and local community based organization should be encouraged to conic forward to participate in the planning, development and management of their local areas. Increasing community participation in collaboration with the planners will help to evolve new concept, new techniques and new theories on the subject.

REFERENCE

Article in journal

Mowla Q. A. (2003) Contemporary planning dilemma in Dhaka. Jahangirnagar Planning Review, Vol.1, pp.13-29.

Alam N. K. M.R & Ullah M.S (1986) Residential Scheme for High and Middle Income Groups in Dhaka city, Bangladesh. World Congress on Land Policy, 1986.

Islam, M. S. & Nabi, A. S. M. M (1990) Population of Dhaka City: Past, Present and future. Journal of Bangladesh Institute of Planners, Vol.1, Nos. 1&2.

News paper

Ali T. (2008) Dhanmondi Residential Area-All about a broken promise. The Daily Star.

Islam K. S. (2004) The Death of Dhaka's Posh Spots. The Daily Star.



Rahaman, J.A, (2008) Dhanmondi losing its Residential Flavor. The Daily Star.

Bhatt A. (2008) Transformations Due To Socio - Economic Pressure. The Daily Star.

Dissertation/ Thesis/ Report

Public Works Department (1958) Ministry of Housing and public Works. Government of Bangladesh.

Public Works Department (1996) Resolution of the Committee Meeting, Section-6/1 M-16/96/78 (22), Date 11/09/96, Ministry of Housing and public Works. Government of Bangladesh.

Public Works Department (1999) Dhamondi Abashik Elakae Obaioho Banijjik/ Onabashik Babahan,Otirikta Zmi Dakhal o RAJUK Onumodito Naksha Bahirvuto Nrman Bishoe Jarip Bobarini,( in bangla) vol.iii. Government of Bangladesh.

RAJUK (1993) Strategic Growth Options-Dhaka 2016. Rajdhani Unnayan Katriphakhya, Dhaka.

RAJUK (1993) Report and recommendation on the Non- Residential Uses in Dhanmondi Residential Area (in Bangla), Town Planning Department. Rajdhani Unnayan Katriphakhya, Dhaka.

RAJUK (1995) Dhaka Metropolitan- Area Development Plan (DMDP). Rajdhani Unnayan Katriphakhya, Dhaka.

RAJUK (2008) Dhaka Metropolitan- Area Development Plan (DMDP). Rajdhani Unnayan Katriphakhy, Dhaka.

Bangladesh Bureau of Statistics (BBS), 2006.

Shafi, S. A. (2005) Growth of Dhaka City and Land Use Changes in Dhanmondi residential Area. Dhanmondi Recollections and Vision, Dhanmondi Poribesh Unnayan Jote, June 2005, Dhaka.

Morshed, K. M. (2008) Transformation of Dhanmondi Residential Area- Causes and Effects, unpublished Master’s term paper in the Department of Architecture, BUET, 2008, Dhaka.

Zerin, I. and Rahman M. (2007) Revitalization of Dhanmondi Residential Area, unpublished Bachelor’s seminar paper in the Department of Architecture, AUST, 2007, Dhaka.

Rahman M. (2006). Development of Valuation Model for Residential Properties, Intregratiting unpublished thesis, School of Architecture.

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Performance Analysis of UMTS Cellular

Network using Sectorization Based on

Capacity and Coverage in Different

Propagation Environment

M. S. Islam1, Jannat-E-Noor

2, Soyoda Marufa Farhana

3

1Assistant Professor, Department of Electrical and Electronic Engineering, Rajshahi University of

Engineering & Technology, Rajshahi, Bangladesh 2&3Department of Electrical and Electronic Engineering, Rajshahi University of Engineering &

Technology, Rajshahi, Bangladesh

ABSTRACT

Performance analysis of umts network is of major interest, because of the WCDMA technique used in umts, which leads to an interference limited system with a dynamic cell capacity and load dependent cell coverage. The performance of umts network depends on sectorization; also, the coverage area depends significantly on the geografical nature and the propagatoin environment of the covered area. In this paper, the capacity and coverage of umts cellular network covering a densed urban area and suburban area are simulated for incrising amount of sectorization showing the number of users and coverage area gradually increased. For modelling the propagatoin, the cost-231 hata model has been used. Key Words: UMTS, Coverage, Propagation Model, WCDMA, Sectorization.

1. INTRODUCTION

Universal Mobile Telecommunications System (UMTS) is one of the standards in 3rd generation partnership project (3GPP). This thesis presents the performance of UMTS cellular network using sectorization for capacity and coverage. The major contribution is to see the impact of sectorization on capacity and cell coverage with independent dynamic parameters as energy per bit to noise spectral density ratio, soft handover factor, voice activity factor, intercell or outercell interference factor, data rates. Bo Hagerman, Davide Imbeni and Jozsef Barta considered WCDMA 6-sector deployment case study of a real installed UMTS-FDD network [1]. Romeo Giuliano, Franco Mazzenga, Francesco Vatalaro described Adaptive Cell Sectorization for UMTS Third Generation CDMA Systems [2]. Achim Wacker, Jaana Laiho-Steffens, Kari Sipila, and Kari Heiska considered the impact of the base station sectorization on WCDMA radio network performance [3]. S. Sharma, A.G. Spilling and A.R. Nix considered Adaptive Coverage for UMTS Macro cells based on Situation Awareness [4]. A.K.M Fazlul Haque, Mir Mohammad Abu Kyum, Md. Baitul Al Sadi, Mrinal Kar and Md. Fokhray Hossain considered UMTS coverage and capacity based on sectorization[5]. Most of the works analyzed the



performance considering sectors with static parameters but it is needed to analyze the performance along with all dynamic parameters and propagation environment. This paper focuses on main factors that affect the coverage and capacity in a CDMA cell based on sectorization and on propagation prediction models COST-231 Hata model.

2. CAPACITY AND COVERAGE CALCULATIONS

The capacity of a CDMA cell depends on many different factors, such as power control accuracy, interference power. In this present study we are considering perfect power control. We begin by calculating the signal-to-noise (interference) power [7, 8].

2.1 Initial Model for Capacity Calculation: In order to calculate the maximum number of

users in a particular cell the following assumptions are made: No inter-cell and intra-cell

interference is present within the cell. All signals arrive at the base station with equal

power Un-limited number of spreading codes are available.

If there are Ns users in a cell and the signal is denoted by S then the interference can

be calculated as I = (Ns −1)S +η , where η is the thermal noise. Hence the SIR is given by

sN

sSNR

s )1(=

SN s /)1(

1

… (1)

Suppose the digital demodulator for each user can operate against the noise at energy per

bit-to noise power density level is given by Eb/No , where Here Eb = S / R and No = I / W

Eb/No=

WI

RS

/

/ ........................................................ (2)

Where, W is the chip rate, R is rate of data communication and I is interference power of

the cell.

Hence using equations (1) and (2) gives

Ns - 1=

ob /NE

RW / -

S

………….………………. (3)

For a uniform population, this reduces the average signal power of all users and

consequently the interference received by each user. This results in an increase in the Eb/No

by a voice activity gain factor, α. Similarly, the cell sectoring factor D also increases the

Eb/No. Finally, we must evaluate the interference mathematically,

β=cellgivenfromceinterferen

cellotherfromceinterferen

Due to the interference, the actual numbers of user will decreases. It is also necessary to

consider the affects of soft handover factor (H), Array antenna gain (Ag).Thus the

capacity for WCDMA in UMTS yields:

NS= 1+ (

ob /NE

RW / -

S

) ×

1

gAHD …...… (4)

2.2 Coverage versus Capacity: The analysis in the above the capacity calculation can be

isolated from coverage. We can understand the performance of a WCDMA network by

developing a simple expression for the ratio S as follows.



S=

g

Sob

ob

AHD

NRNEW

RNE

11)(

)( …...… (5)

We focus on the coverage by user 1 when the number of users in the cell is Ns. Let r be the

distance of user 1 from the base station. The received power at the base station from

mobile user l, S, is given by

S = S1 − P (d) – Z ………………...…………… (6)

Where, S1 the transmission power of the user, P (d) is the propagation loss at distance d

from the MS to BS, Z the shadow fading.

2.3 Coverage Area in different Propagation Environment: The propagation losses in

densed urban and suburban areas are usually calculated by using propagation models. In

the present study we utilized COST 231-Hata model for urban and dense urban

environment. Where higher data rates need higher processing gain resulting in smaller

coverage area. But increasing sectors with same parameters makes extensive coverage for

higher data rates. The COST-Hata-Model is formulated as,

For densed urban environments the path loss:

L = 46.3 + 33.9 log (f) - 13.82 log hb - 3.2

[log (11.75h UE )]2 + 4.97 + (44.9 - 6.55 log hb)

log d + 3 ………...…………………………(7)

For suburban or rural environments the path loss:

L = 46.3 + 33.9 log (f) - 13.82 log hb – {(1.1 log f –

0.7) hUE - (1.6 log f -0.8)} + (44.9 - 6.55 log hb)

log d ………....…………………………… (8)

Where d is the coverage radius and R is the data rates. After calculating the cell range d,

the coverage area can be calculated. The coverage area for one cell in hexagonal

configuration can be estimated with [6]

Coverage area, A =K.d2 ……………………….... (9)

Where A is the coverage area, d is the maximum cell range, and K is a constant. K values

for the site area calculation [6]: K=2.6, 1.3, 1.95, 2.6 for sector one, two, three, four

respectively.

3. SIMULATION & RESULT

The analysis has been done for capacity and coverage with sectoring cell for dense urban

and suburban area using MATLAB R2008a. From this figure 1 it is observed the Number

of simultaneous 384 Kbps users vs. Eb/No in sectors cell.



Figure 1: Number of simultaneous 384 Kbps users Vs. Eb/No in sectors cell

Table 1: simulated values for Figure 1

Eb/No User With

Out sector

User with

2 sectors

User with

4 Sectors

User with

6 Sectors

User with

8 Sec-tors

1 58 115 229 343 457

5 12.22 23.44 45.88 68.32 90.76

10 6.5 12 23 34 45

15 4.59 8.179 15.30 22.54 29.72

20 3.636 6.271 11.54 16.81 22.09

The interference from other cell is known as inter-cell interference (β). Figure 2 represents,

Figure 2: Number of simultaneous 384 Kbps users vs. inter-cell interference in sectors cell


β User With

Out sector

User With

2 sector

User with

4 sector

User with

6 sector

User with

8 Sector

0.1 1195.4 2390 4778.5 7167.3 9556

0.5 876.9 1753 3504.5 5256.3 700.8

1 657.9 1315 2628.6 3942.4 525.6

1.5 526.5 1052 2103.1 3154.2 420.5

2 438.9 876.9 1752.8 2628.6 350.5

0 5 10 15 200

50

100

150

200

250

300

350

400

450

500 Number of simultaneous 384 Kbps users vs. Eb/No in UMTS cell

Eb/No

Num

ber

of

sim

ult

an

eo

us 3

84

kbp

s u

se

rs

without sector

2 sectors

3 sectors

4 sectors

5 sectors

6 sectors

7 sectors

8 sectors

0 0.5 1 1.5 2

102

103

104

Number of simultaneous 384 Kbps users vs.inter-cell interference in sectors cell

Intercell interference factor

Num

ber

of s

imul

tane

ous

384

kbps

use

rs

without sector

2 sectors

3 sectors

4 sectors

5 sectors

6 sectors

7 sectors

8 sectors



Figure 3 shows that for increasing H and changing value of sectorization the number of

simultaneous 384 Kbps data users increases.

Figure 3: Number of simultaneous 384 Kbps users vs. soft handover factor in sectors cell

Table 3: simulated values Figure 3

H User With

Out Sector

User with

2 sectors

User with

4 Sectors

User with

6 Sectors

User with

8 Sectors

0.1 8.37 15.37 30.46 45.22 59.96

0.5 37.85 74.7 148.4 222.10 295.8

1 74.70 148.40 295.8 443.20 590.6

1.5 111.5 222.10 443.2 664.31 885.4

2 148.4 295.80 590.6 885.41 1180.2

Figure 4: Number of simultaneous voice users vs. voice activity factor in sectors cell.


α User With

Out Sector

User with

2 sectors

User with

4 sectors

User with

6 sectors

User with

8 sectors

0.2 236.6 472.25 943.5 1414.8 1886

0.4 118.8 236.63 472.2 707.9 943.5

0.6 79.54 158.08 315.1 472.3 629.3

0.8 59.90 118.81 236.6 354.4 472.3

1 48.12 95.251 189.5 283.8 378.0

0 0.5 1 1.5 2

101

102

103

Number of simultaneous 384 Kbps users vs. Handover factor in UMTS cell

Handover factor

Num

ber

of

sim

ult

ane

ous

384

kbp

s u

sers

without sector

2 sectors

3 sectors

4 sectors

5 sectors

6 sectors

7 sectors

8 sectors

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

500

1000

1500

2000

2500

3000

3500

4000Number of simultaneous voice users vs. voice activity factor in sectors cell.

Voice activity factor

Num

ber

of

sim

ult

an

eo

us 3

84

kbp

s u

se

rs

without sector

2 sectors

3 sectors

4 sectors

5 sectors

6 sectors

7 sectors

8 sectors



Finally, consider for coverage vs. data rates in dense urban area and suburban area, where

operating frequency is considered 2000 MHz with COST 231 Model as a radio

propagation model.

Figure 5: Coverage vs. bit rates for dense urban using COST 231 model in sectors cell


Data rate

Kbps

Cell range

In (km)

Area with-out

sector (km2)

Area with 2

Sec-tors (km2)

Area with 3

Sec-tors (km2)

Area with 4

Sec-tors (km2)

100 0.6263 0.5099 0.6275 0.7648 1.0197

500 0.2261 0.0664 0.0818 0.0997 0.1329

1500 0.1128 0.0165 0.0203 0.0248 0.0331

2000 0.0940 0.0115 0.0141 0.0172 0.0230

Figure 6: Coverage vs. bit rates for sub urban using COST 231 model in sectors cell


Data rate

(Kbps)

Cell range

in (km)

Area without

sector (km2)

Area with 2

sectors (km2)

Area with 3

sectors (km2)

Area with 4

sectors (km2)

100 0.8068 0.8461 1.0414 1.2692 1.6922

500 0.2912 0.1103 0.1357 0.1654 0.2205

1500 0.1453 0.0274 0.0338 0.0411 0.0549

2000 0.1211 0.0191 0.0235 0.0286 0.0381

0 500 1000 1500 20000

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

Coverage vs. bit rates for dense urban using COST 231 model in sectors cell

Data rate in kbps

Cove

rag

e a

rea i

n s

qu

are

km

& c

ell r

an

ge

in k

m

Cell area without sector

Cell area using 2 sector



Cell range

0 500 1000 1500 20000

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8Coverage vs. bit rates for suburban using COST 231 model in sectors cell

Data rate in kbps

Cov

era

ge

are

a in

sq

uar

e k

m &

ce

ll ra

nge

in

km

Cell area without sector




Cell range



Figure7: Coverage vs. bit rates for dense urban & suburban environment for a cell using 4 sectors


Data rate

(Kbps)

Coverage in densed

Urban areas in km2

Coverage in sub

Urban areas in km2

100 1.0197 1.6922

500 0.1329 0.2205

1500 0.0331 0.0549

2000 0.0230 0.0381

Figure8: Coverage range vs. bit rates for dense urban & suburban environment.


Data rate

(Kbps)

Coverage in densed

Urban areas in km

Coverage in sub

Urban areas in km

100 0.6263 0.8068

500 0.2261 0.2912

1000 0.1458 0.1878

1500 0.1128 0.1453

2000 0.0940 0.1211

4. CONCLUSION

In this paper the coverage and capacity in a CDMA cell based on sectorization and

propagation prediction models COST-231 Hata model is analyzed. It has been seen that,

the performance of an UMTS network can be improved using sectorization. It is also

observed that, both the coverage area and coverage range is more in a suburban area than

a densed urban area.

0 500 1000 1500 20000

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8Coverage vs. bit rates for dense urban & suburban environment for a cell using four sectors

Data rate in kbps

Cov

erag

e ar

ea in

squ

are

km

Densed urban area

Suburban area

0 500 1000 1500 20000

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9Coverage range vs. bit rates for dense urban & suburban environment for UMTS a cell

Data rate in kbps

Cel

l cov

erag

e ra

nge

in k

m

Densed urban area

Suburban area



5. FUTURE WORK

Although this research tried to give an impression of the main factors affecting the capacity

and coverage. For future research more attention has to be drawn to quality of service

requirements in the system and more accurate model can be used for evaluating path loss.

Table 9: Parameters used in our simulations

Parameter Value

Eb/No 3 db

Frequency 2 GHz

Chip rate 3.84 Mcps

voice activity (α) 1

thermal noise (η) -173.93

signal power (S1) 21dbm

shadow fading 8db

inter-cell interference (β) 0.1

cell range(d) 2km

base antenna height (hb) 20m

user antenna height (hUE) 2m

antenna gain (Ag) 2db

data rate (R) 12.2,64,144,384,2000kbps

sector (D) [1 2 3 4 5 6 7 8]

REFERENCES

[1] Bo Hagerman, Davide Imbeni and Jozsef Barta ‚WCDMA 6 - sector Deployment-

Case Study of a Real Installed UMTS-FDD Network‛ IEEE Vehicular

Technology Conference, spring 2006.

[2] S. Sharma, A.G. Spilling and A.R. Nix ‚Adaptive Coverage for UMTS Macro cells

based on Situation Awareness‛, IEEE Vehicular Technology Conference, spring

2001, page(s):2786 - 2790

[3] A. Wacker, J. Laiho-Steffens, K. Sipila, K. Heiska, "The impact of the base station

sectorisation on WCDMA radio network performance", IEEE Vehicular

Technology Conference ,September 1999.

[4] Romeo Giuliano, Franco Mazzenga, Francesco Vatalaro, ‚Adaptive cell sectorization

for UMTS Third generation CDMA systems‛ IEEE Vehicular Technology

Conference, May 2001.

[6] Jaana Laiho, Achim Wacker, Tomas Novosad, ‚Radio Network Planning and

Optimisation for UMTS‛ -Second Edition John Wiley & Sons.

[7] Rappaport T.S; Wireless Communications: Principles and Practice, Prentice Hall, 2002.

[8] Gilhousen K.S,et al; On the Capacity of a Cellular CDMA System, IEEE Trans. on VT,

Vol. 40, No. 2, pp.303-312, May 1991.

Asian Business Consortium is an independent research house committed to

publishing and delivering superior, Peer-reviewed standard research



Effect of Injection Pressure on the Perfomance and

Emissions of Nerium Biodiesel Operated Diesel

Engine

Dr. Vinai K.Singh

Professor, Department of Applied Mathematics & Dean Academic, Raj Kumar Goel Engineering

College, Ghaziabad U.P., INDIA

ABSTRACT

Use of vegetable oil in unmodiled diesel engines leads to lower thermal efficiency and higher smoke emission. In this project esterified Nerium oil is used as an alternate fuel. A single cylinder stationary kirloskar engine is used to compare the performance and emission characteristics between pure diesel and Nerium blends. In this project selection of suitable nerium blend and selection of optimized injection pressure for the blend is done. The Nerium oil blends are in percentage of 20%, 40%, 60%, 80%, and 100% of Nerium oil to 80%, 60%, 40%, 20% & 0% of diesel. From this project it is concluded that among all nerium and diesel blends 20% of nerium and 80% of diesel blend with injection pressure 220 bar gives better performance nearing the diesel. When comparing the emission characteristics HC, CO is reduced when compared to diesel, however NOx emission is slightly increased when compared to diesel. Hence Nerium blend can be used in existing diesel engines with minimum modification in the engine. It also describes the usage of non-edible oil to a greater extent. At present neither Nerium oil nor bio-diesel of Nerium oil is available in the market. Hence for our work, well grown Nerium seeds are collected in Salem District around 500kgs of Nerium seeds are collected. After the processing of these seeds, oil was extracted. . Approximately 10 liters of oil is obtained from the 20 kg of nerium seed. Then after proper filtration, esters of Nerium oil are prepared using the bio-diesel plant available in the department. Keywords: Nerium, Injection pressure, Esterification.

1. INTRODUCTION

Vegetable oils are considered as good alternative to diesel fuel due to their properties which

are much closer to that of diesel. Thus, they offer the advantage of being readily used in

existing diesel engines without much modification. They have a reasonably high cetane

number. Vegetable oils have a structure similar to that of diesel fuel, but differ in the type of

linkage of the chains and have a higher molecular mass and viscosity. The heating value is

approximately 90% of diesel fuel. A limitation on the utilization of vegetable oil is its cost.

In the present market the price of vegetable oil is higher than that of diesel. However, it is



anticipated that in future the cost of vegetable oil will get reduced as a result of

developments in agricultural methods and oil extraction techniques.

In India, forests and plants based non-edible oils are considered as the main sources for bio

diesel production. Non – edible oils can be obtained plant species such as Jatropha, Karanja,

Rubber, Mahua and Neem. However, it is not possible for us to get Nerium oil that much

easily as that of other oils. Hence, in the present work, Nerium oil based bio-diesel is being

considered as an alternate fuel for Diesel engines.

2. EXPERIMENTAL APPARATUS AND METHODS

2.1 TRANSESTERIFICATION OF NERIUM OIL

To reduce the viscosity of the Nerium oil, trans-esterification method is adopted for the

preparation of biodiesel. The procedure involved in this method is as follows: 1000 ml of

nerium oil is taken in a three way flask. 12 grams of Potassium hydroxide (KOH) and 200

ml of methanol (CH3OH) are taken in a beaker. The Potassium hydroxide and the alcohol

are thoroughly mixed until it is properly dissolved. The solution obtained is mixed with

Nerium oil in three way flask and it is stirred properly. The methoxide solution with

nerium oil is heated to 60ºC and it is continuously stirred at constant rate for 1 hour by

stirrer. The solution is poured down to the separating beaker and is allowed to settle for 4

hours. The glycerin settles at the bottom and the methyl ester floats at the top (coarse

biodiesel). Methyl ester is separated from the glycerin. This coarse biodiesel is heated above

1000C and maintained for 10-15 minutes to remove the untreated methanol. Certain

impurities like sodium hydroxide (KOH) etc are still dissolved in the obtained coarse

biodiesel. These impurities are cleaned up by washing with 350 ml of water for 1000 ml of

coarse biodiesel. This cleaned biodiesel is the methyl ester of Nerium oil. This bio-diesel of

Nerium oil is being used for the performance and emission analysis in a diesel engine. For

the present work N20, N40, N60, N80 and N100 blends of Nerium oil bio diesel are being

used.

2.2 ENGINE SPECIFICATION Engine manufacturer -Kirloskar engines ltd

Bore& stroke -87.5 x 110 (mm)

Number of cylinders -1

Compression ratio - 17.5: 1

Speed -1800 rpm

Cubic capacity -0.661 litres

Method of cooling -water cooled

Fuel timing -27º by spill (btdc)

Clearance volume -37.8 cc

Rated power -7 and 8 hp

Nozzle opening pressure -200 bars

2.3 EXPERIMENTAL SETUP

The engine used for the investigation is kirloskar SV1, single cylinder, four stroke, constant

speed, vertical, water cooled, high speed compression ignition diesel engine. The kirloskar

Engine is mounted on the ground. The test engine was directly coupled to an eddy current

dynamometer with suitable switching and control facility for loading the engine. The liquid

fuel flow rate was measured on the volumetric basis using a burette and a stopwatch. AVL

smoke meter was used to measure the CO and HC emissions from the engine. The NOX



emission from the test engine was measured by chemical luminescent detector type NOX

analyser. For the measurement of cylinder pressure, a pressure transducer was fitted on

engine cylinder head and a crank angle encoder was used for the measurement of crank

angle. The sound from the engine was measured by Rion sound level meter. The

experimental setup is shown in the Fig.1

2.4 TEST METHOD

The engine was operated initially on diesel for warm up and then with Nerium oil blends.

The experiment aims at determining appropriate proportions of biodiesel and diesel for

which higher efficiency was obtainable. Hence experiments were conducted for different

proportions of biodiesel mixed with diesel. The blends were in the ratio 20%, 40%, 60%,

80%, and 100% with diesel. First these blends were tested at normal injection pressure 200

bar at constant injection timing 27° BTDC and with a constant compression ratio 17.5.Then

for the best efficiency blend, the test were conducted at three different injection pressures

180 bar, 220 bar and 240 bar and above procedure was followed. An injector pressure

nozzle was used to change the injection pressure.



3. PERFORMANCE ANALYSIS

3.1 BRAKE THERMAL EFFICIENCY

Figure 2.1 Percentage of nerium oil with diesel

At normal injection pressure of 180 bar the brake thermal efficiency for neat diesel at full

load is 26.48 %,where as it was 24.08% ,23.56% ,22.45% ,21.923% , 21.07% for

N20,N40,N60,N80 and N100 as shown in Fig 2.1.The best thermal efficiency was obtained

for N20 blend and was 2.4% less than that of diesel for full load. From the Fig 2.2 it was

observed that brake thermal efficiency for different injection pressures for best efficiency

blend(N20) at 180 bar was 20.09%,220 bar was 25.12% and 240 bar was 24.11%.For N20 at

220 bar it was found to be 1.04% higher than N20 at 200 bar.

Figure 2.2 variation of BTE with BP for different injection pressures for best efficiency blend

This may be due to better spray characteristics and effective utilization of air resulting in

complete combustion of the fuel. For 180 bar the brake thermal efficiency is 3.99% less than

normal the efficiency of injection pressure. This is because of incomplete combustion due to

retardation of injection pressure.

3.2 SPECIFIC ENERGY CONSUMPTION

Comparison of the specific energy consumption for the four different injection pressures for

best efficiency blend (N20) is shown in Fig no.3. It can be seen that the SEC is the highest in

0

5

10

15

20

25

30

0 5 10

BTE

(%

)

BRAKE POWER (kW)

DIESEL

N 20

N 40

N 60

N 80

N 100

0

5

10

15

20

25

30

0 2 4 6 8

BTE

(%

)

BRAKE POWER(KW)

180 bar

200 bar

220 bar

240 bar



the case of the 240 bar and is least in the case of 220 bar. This is because at 220 bar the fuel is

optimally injected such that proper diffusion of the biodiesel takes place.

Figure 3 variation of SEC with BP for different injection pressures for best efficiency blend

4. EMISSION ANALYSIS

4.1 UNBURNT HYDROCARBON EMISSIONS & CARBON MONOXIDE

Figure 4 variation of UBHC with BP for different injection pressures for best efficiency

blend

Figure 5 variation of CO with BP for different injection pressures for best efficiency blend

0

0.2

0.4

0.6

0.8

0 5 10

SFC

(K

g/K

w-h

r)

BRAKE POWER(KW)

180 bar

200 bar

220 bar

240 bar

0

20

40

60

80

0 2 4 6 8

HC

(PP

M)

BRAKE POWER(KW)

180 bar

200 bar

220 bar

240 bar

0

0.05

0.1

0.15

0.2

0 5 10

CO

(%)

BRAKE POWER(KW)

180 bar

200 bar

220 bar

240 bar



Comparison of the UBHC emissions for the four different injection pressures for best efficiency

blend (N20) is shown in Fig no.4. Comparison of the carbon monoxide emissions for the four

different injection pressures for best efficiency blend (N20) is shown in Fig no5. In both cases it

can be seen that the UBHC and carbon monoxide emission is the highest in the case of the 180

bar and is least in the case of 220 bar. This is because at 220 bar proper diffusion and combustion

of the biodiesel takes place which results in lower emissions. At 180 bar and 200 bar there is very

less time for the diffusion of the fuel to takes place which leads to increase in emissions.

4.2 OXIDES OF NITROGEN & CARBON DI-OXIDE

Comparison of the oxides of nitrogen emissions for the four different injection pressures for

best efficiency blend (N20) is shown in Fig no.6. Comparison of the carbon di-oxide

emissions for the four different injection pressures for best efficiency blend (N20) is shown

in Fig no7. In both cases it can be seen that the oxides of nitrogen and carbon di-oxide

emission is the highest in the case of the 220 bar and is least in the case of 180 bar. This is

because at 220 bar the peak temperature in the combustion chamber increases due to the

proper combustion which leads to increase in emissions. At 240 bar because of the

advancement in injection pressure, the peak pressure is lowered due to poor combustion.

At 180 bar and 200 bar due to the poor combustion and spray characteristics, the oxygen

content in the fuel is not fully burnt which results in lower emissions.

Figure 6 variation of NOx with BP for different injection pressures for best efficiency blend

Figure 7 variation of CO2 with BP for different injection pressures for best efficiency blend

0

100

200

300

400

500

600

700

800

0 5 10

NO

x(P

PM

)

BRAKE POWER(KW)

180 bar

200 bar

220 bar

240 bar

0

0.5

1

1.5

2

0 2 4 6 8

CO

2(%

)

BRAKE POWER(KW)

180 bar

200 bar

220 bar

240 bar



4.3 SOUND CHARACTERISTICS

Comparison of the sound characteristics for the four different injection pressures for best

efficiency blend (N20) is shown in Fig no.8. It can be seen that the sound characteristics is

the highest in the case of the 240 bar and is least in the case of 220 bar. This is because at 220

bar the proper combustion takes places and due to this the power developed helps in

smooth running which results in lower noise level. At 180 bar and 200 bar due to improper

combustion the noise level is marginally greater. At 240 bar due to higher amount of fuel

accumulation in the combustion chamber initially, the engine tends to knock and this leads

to increase in noise level.

Figure 8 Variation of noise level with BP for different injection pressures for best efficiency blend

5. COMBUSTION ANALYSIS

5.1 PEAK PRESSURE RISE

Comparison of the peak pressure rise for the four different injection pressures for best

efficiency blend (N20) is shown in Fig no.9. Peak pressure for pure diesel at 200 bar is 72

bar. Peak pressure of N20 for 220 bar is 68.4 bar, 240 bar is 66.5 bar, 200 bar is 66 bar and 180

is 60.2 bar. This is because complete usage of the fuel is observed at 220 bar which results in

increase in the pressure as a result of proper combustion. At 240 bar due to increase in

delay period, proper diffusion does not take place which results in lower pressure in the

combustion chamber.

Figure 9 variation of peak pressure with crank angle for different injection pressures for best efficiency blend.

80

82

84

86

88

90

92

0 2 4 6 8

SOU

ND

(de

cib

le)

BRAKE POWER(KW)

180 bar

200 bar

220 bar

240 bar

-10

0

10

20

30

40

50

60

70

80

180 280 380 480

PR

ESSU

RE(

bar

)

CRANK ANGLE(deg)

180 bar

200 bar

220 bar

240 bar



5.2 INSTANTANEOUS HEAT RELEASE RATE

Comparison of the instantaneous heat release rate for the four different injection pressures for

best efficiency blend (N20) is shown in Fig no.10. Instantaneous Heat release rate for pure diesel

is 76.50 J/deg CA at 200 bar. Heat release rate of N20 for 220 bar is 79.1 J/deg CA, 240 bar is

80.10 J/deg CA, 200 bar is 80.23 J/deg CA, and 180 bar is 87.12 J/deg CA. This is because at 220

bar, the increase in thermal efficiency indicates the complete burning of fuel and lower release of

the heat to the exhaust and this reduces the instantaneous heat release rate. At 240 bar because of

poor combustion the heat release rate is marginally higher. At 180 bar and 200 bar because of

poor diffusion which causes the hot exhaust gases to escape out at a higher rate.

Figure 10 Instantaneous heat release rate with crank angle for different injection pressures

for best efficiency blend

5.3 CUMULATIVE HEAT RELEASE RATE

Comparison of the cumulative heat release rate for the four different injection pressures for best

efficiency blend (N20) is shown in Fig no.11. Cumulative heat release rate for pure diesel is

329.04 J/deg CA at 200 bar. Cumulative heat release rate of N20 for 220 bar is 339.26 J/deg CA,

240 bar is 345.63 J/deg CA, 200 bar is 349.048 J/deg CA, and 180 bar is 371.2 J/deg CA.

This is because at 220 bar due to proper combustion, the amount of heat released is lower as

the heat is utilized to produce better efficiency resulting in lower cumulative heat release

rate. At 240 bar the cumulative heat release rate is higher due to improper burning at

different zones in the combustion chamber. At 180 bar and 200 bar because of poor

combustion, which causes the cumulative heat release rate to rise higher.

Figure 11 Variation of Cumulative heat release rate with crank angle for different injection pressure for best efficiency blend

-100

-50

0

50

100

180 280 380 480 580

HR

R (

J/d

eg

CA

)

CRANK ANGLE(deg)

180 bar

200 bar

220 bar

240 bar

-50

0

50

100

150

200

250

300

350

400

180 280 380 480 580

CU

M M

. H

RR

( J/d

eg

CA

)

CRANK ANGLE(deg)

180 bar

200 bar

220 bar

240 bar



6. CONCLUSION

From the above results and discussions, the following important points are observed and

the effect of injection timing are listed,

Nerium oil, being non-edible oil proves to be a very effective alternate fuel.

After trans-esterification of Nerium oil, the kinematic viscosity and density is reduced

while the calorific value is increased.

For Nerium oil, fuel injection pressure at 220 bar results in approximately 1.04% rise in

BTE when compared to 200 bar for N20 blend.

The UBHC, CO is significantly reduced with biodiesels and its blends.

Compared to diesel fuel, NOx emissions are high for nerium blends.

Based on the engine performance and emission tests, at 220 bar, the 20% blends of

methyl esters with nerium fuel have better performance and lower emissions

characteististics compared to other injection pressures.

From the above conclusions it can be concluded that a significant improvement in the

performance and emissions are observed if the blend and injection pressure are properly

optimized when a diesel engine is to be operated with methyl ester of nerium oil.

REFERENCES

[1] A.K Babu and G. Devaradjane,‛Vegitable Oil and Their Derivatives as Alternate Fuels

for CI Engines an Overview‛, SAE 2003-01-0767.

[2] O.J.Abayeh, E.C. Omuoha and I.A. Ugah,‛TransesterifiedThevitaNerifolia Oil As A

Bio-Diesel‛, Global Journal Of Environmental Research 1(3):124-127, 2007.

[3] T Balusamy, R Marappan,‚Performance Evaluation Of Direct Injection

[3] Diesel With Blends Of ThevitaPeruviana Seed Oil And Diesel‛. J SciInd Res, Vol.66

Dec 2007, pp. 1035-1040

[4]. Murugasen.A ‚Experimental and Theoretical Investigation of using biodiesel in

Diesel engines‛ Ph.D. ,Thesis. AnnaUniversity, Chennai.

[5] Peterson, C.L., Wagner, G.L. &Auld, D.L., ‚Vegetable oil substitution for diesel fuel‛,

Transaction of ASAE, 26, 1983, pp 322-327.

[6] Gerhard. Vellguth (1983), "Performance of Vegetable oils and their monsters as fuels

for "Diesel Engines", SAE Paper 831358.

[7] Kyle W. Scholl and Spencer C. Sorenson, "Combustion of soybean oil methyl ester in a

direct injection diesel engine", SAE 930934 (SP - 958).

[8] Y.Ra ‚The use of variable geometry sprays with low pressure injection for

optimization of diesel HCCI engine combustion‛- SAE journal (2005-01-0148)

[9] Heywood J.B., "Internal Combustion Engine Fundamentals", McGraw Hill Book

Co., 1989.

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Effects of Excess Bi2O3 on the Properties of

La- doped Bismuth titanate (Bi4Ti3O12)

Ferroelectric Ceramics

Md. Aminul Islam1, Dr. Abdul Gafur

2, Dr. M. Saidul Islam

1

1Department of Materials Science & Engineering, Rajshahi University, Bangladesh 2PP&PDC, BCSIR Dhaka, Bangladesh

ABSTRACT

In this paper, it was examined the effects of excess Bi2O3 on the properties of La-doped Bi4Ti3O12 (BLT) and further explore the processing parameters that affect the structure and ferroelectric properties of this oxide. BLT ceramics were prepared by solid state method with varying the excess amount of Bi2O3 content as, 0 mol%, 5 mol% and 10 mol%. IR was taken to conform the TiO6 formation, Crystal structure was examined by XRD. A small amount of excess Bi2O3 improves the crystalinity and dielectric properties of BLT ceramics. The better result was obtained at 10 mol% excess Bi2O3 with dielectric constant & dielectric loss of 236 & .0096 respectively.

Key words: Bismuth titanate, Lanthanum dope, excess Bi2O3

INTRODUCTION

Bismuth layer-structured ferroelectrics are thought to be promising materials for lead-free

ferroelectric oxides for their device applications to sensors, actuators, and nonvolatile

random access memories (NvRAMs). Among them, Bismuth titanate Bi4Ti3O12 (BIT) has

attracted much attention for potential utilization due to its large spontaneous polarization

(Ps), low processing temperature, and high Curie temperature (TC 675o C.)[1]. The

ferroelectric properties of BIT can be improved by adding an appropriate amount of rare

earth substitutions which replace either Bi3+ or Ti4+ or both. Among them lanthanum doped

bismuth titanates have been demonstrated to be a good candidate materials for FRAMs [2,

3]. Park et al.[4]reported that La-substituted BIT (BLT) film has a large Pr, low processing

temperature and fatigue-free characteristics at composition (Bi3.25La0.75Ti3O12,)

The aim of this paper is to examine the effects of excess Bi2O3 on La-doped Bi4Ti3O12 (BLT)

and to further explore the processing parameters that affect the structure and ferroelectric

properties of this oxide. To vary the Bi2O3 content, ceramic targets with varying amounts

of excess bismuth (0–10 mol% Bi2O3) were made.



EXPERIMENTAL PROCEDURES

Staring powders

Based on the previous work’s results *4+ the composition of Lanthanum (La) doped

Bismuth titanate (BLT) was fixed as (Bi3.25La0.75Ti3O12). Bulk ceramics was prepared using

the conventional solid-state reaction method with starting materials, bismuth oxide (Bi2O3,

99.9% pure, MERCK, Germany), Lanthanum oxide (La2O3, 99.99% pure, Wako pure

chemical industries Ltd, Japan), titanium oxide (TiO2, > 99% pure, MERCK, Mumbai Ltd,

India).

Processing

The powders weighed according to the composition and amount of excess bismuth oxide

(Bi2O3) were varied from 0 mol% to 10 mol% then milled in absolute alcohol for 24 hours

After ball milling the mixture was kept for settle down for 24 hours in a bicker to

precipitate the mixed powder at the bottom of it. The ethanol was then removed from the

upper portion of it and the precipitate powder was taken in an oven for drying. The dried

powder was then grounded in a mortar pestle to form into fine powder. Dried powders

were calcined at 800 0 C for 2 h. Calcined powder was weighted and mixed with 2.5%

PVA solution and dried powers uniaxially pressed at 60 KN to form pellet having radius

and thickness about 0.6cm and 0.15cm respectively. The compact pellets were sintered in

air at temperature 900 0 C for 1 h.

Characterizations

Infrared spectra of the samples were collected by FTIR spectrophotometer (spectrum 100,

Perkin Elmer) situated at the Central Science Laboratory, University of Rajshahi over the

range of wave number 2000 – 300 cm-1. The resolution of the instrument was 1 cm-1.Their

crystal structures were analyzed X-ray diffractometer from the BCSIR Lab (Dhaka,

Bangladesh) using Cu Kα radiation(λ=1.54A0). The dielectric properties were measured by

precision impedance analyzer, Model 4294A, Agilent Technologies, Japan. Before

measurement of dielectric properties, silver past was coated on the both surface of pellets.

RESULT AND DISCUSSION

IR analysis

The FTIR spectrum of the Bi3.25La0.75Ti3O12,(BLT) ceramic powder was recorded at the room

temperature and is shown in Fig. 1. Three sharp bands at 817cm-1, 602 cm-1and 404 cm-1 are

observed. The former two bands are ascribed to the Ti–O stretching vibrations, while the

latter one to the Ti–O bending vibrations [5, 6]. While band at 1627 cm-1, 1384 cm-1 and

band at 938cm-1 indicate Bi-O bond. The former two bands are due to bending vibrations

and later is due to stretching vibration of Bi-O bond [7].



400600800100012001400160018002000

Tra

nsm

ittan

ce (

arb.

uni

t)

Wave number (cm-1

)

10 mol% excess Bi2O

3

5 mol% excess Bi2O

3

0 mol% excess Bi2O

3

1627 817 602

938

404

14651384

Fig.1 FTIR spectra of BLT having different amount of excess Bi2O3.

Crystal structure

Figure 2 shows XRD spectra for BLT ceramics derived from the different Bi2O3 excesses.

The layered perovskite (117) peak and other perovskite (00l) peaks were found in XRD

patterns, which agreed with peaks of BIT ceramics. This indicates that BLT single phases

having BLSF crystal structure were confirmed for the different Bi2O3 excesses contents,

with no apparent impurity phase.

20 25 30 35 40 45 50 55 60

Inte

nsi

ty (

arb

. un

it)

10 mol % Bi2O

3 excess

0 mol % Bi2O

3 excess

5 mol % Bi2O

3 excess

(117)

(008)

(111)

(11

5)

(00

10

)

(20

0)&

(02

0)

(00

14

)

(02

8)&

(20

8)

(11

15

)

(20

14

)

(31

7)

2 (degree)

Fig. 2 XRD patterns of the BLT ceramics with different amount of excess Bi2O3.



Dielectric properties

Dielectric properties of the three BLT ceramics are plotted in Fig. 3. Dielectric properties were

measured at room temperature as a function of frequency in the range from 1 kHz to 1 MHz. It

is observed that the dielectric constant of the samples are high at lower frequency region,

decreases with increase of frequency by approaching approximately a constant value after10

KHz. It is possible that this decrease in the dielectric constant in this frequency range is due to

cheese of space charge, ionic and orientation polarization at higher frequencies.[8] Increasing

the excess Bi2O3 content greatly enhances the dielectric constant, and highest result obtained at

10 mol%. At high temperature Bi3+ ions evaporated which is minimized by the excess Bi2O3 and

at 10 mol% excess Bi2O3 grain growth and crystallinity enhanced. Dielectric constant of 10

mol% excess Bi2O3 BLT was 236 and a dielectric loss was 0.0096 which are comparable to those

previously reported, for the bismuth-layered perovskite structures.

0

100

200

300

400

500

2 3 4 5 6 7 8 9 10

0 mol% excess Bi2O

3 BLT

5 mol % excess Bi2O

3 BLT

10 mol % excess Bi2O

3 BLT

Die

lect

ric

cono

stan

t

Frequency x 105(Hz)

Fig 3 Frequency dependent dielectric constant for the BLT ceramics with different amount of excess Bi2O3.

-0.5

0

0.5

1

1.5

2 4 6 8 10 12

0 mol% excess Bi2O

3 BLT

5 mol % excess Bi2O

3 BLT

10 mol % excess Bi2O

3 BLT

Die

lect

ric L

oss

Frequency x 105(Hz)

Fig. 4 Frequency dependent dielectric loss for the BLT ceramics with different amount of excess Bi2O3.



0

10

20

30

40

50

0 2 4 6 8 10 12

10 mol% excess5 mol% excess

0 mol% excess

Co

nduc

tanc

e x

10

-6(S

)

Frequency x 105(Hz)

Fig. 5 Frequency dependent A-C conductance for the BLT ceramics with different amount of excess Bi2O3.

Conductivity

A-C conductivity has been measured by impedance analyzer, where conductance was

taken from 1k Hz frequency to 1M Hz frequency with applying oscillating voltage of

300mVolt. Fig. 4 shows that a-c conductance increases with frequency according to the

equation σ = ωε״, where σ is conductivity, ω= 2πf (f=frequency) and ε״ is dielectric loss

factor. Conductivity has been decreased due to increasing the amount of excess Bi2O3

content and lowest conductivity is obtained at 10 mol% excess Bi2O3.

CONCLUSION

BLT ceramics of single phase layered structure were synthesized with varying amount of

excess Bi2O3 by solid state reaction method. An appropriate amount of excess Bi2O3

enhances the dielectric properties of BLT ceramics. Better result obtained for 10 mol%

excess Bi2O3 BLT exhibiting dielectric constant of 236 and a dielectric loss of 0.0096.

REFERENCES

1. S.E. Cummings, L.E. Cross, J. Appl. Phys. 39 (5) (1968) 2268–2274.

2. A. Kingon, Nature, 401 658–9 (1999).

3. B. H. Park, B. S. Kang, S. D. Bu, T.W. Noh, J. Lee, andW. Jo, Nature, 401 682–4 (2002).

4. Park P. H, Kang B. B, Bu S. D, Noh T. W, Lee J. and Jo W. (1999) Nature 401 682

5. N. Pavlovic, D. Kancko, K.M. Szecsenyi, V.V. Srdic, 3, 88-95, (2009).

6. Y.Kan, P. Li, Y. Cheng, D. Yan, Mater. Lett., 56 910-914, (2002).

7. S. Supriya, S. Kalainathan and S. Swaroop, International Journal of Chem. Tech

Research, 3, 488-494, (2011).

8. W.D. Kingery, Introduction to Ceramic, John Wiley & Sons, Inc. New York, (1967)



Relativistic Rule of Multiplication of Velocities

Consistent with Lorentz – Einstein Law of

Addition and Derivation of the Missing

Equations of Special Relativity

Dr. M.O.G. Talukder1, & Dr. Mushfiq Ahmad

2

1Barendra University, Rajshahi, Bangladesh 2Department of Physics, Rajshahi University, Rajshahi, Bangladesh

ABSTRACT

In this paper, we present the rule for relativistic multiplication of a velocity by a number. We have reasoned on the basis of a thought experiment and we have taken into consideration the L-E law of addition of velocities. The formalism gives the result of repeated L-E addition just as ordinary multiplication gives the effect of repeated Galilean addition. In the classical limit, it complies with the Galilean law of multiplication. The formalism presented here can extend the horizon of relativity. The thought experiment also reveals the values of both the relative length and time in the longitudinal direction. Further, it has been demonstrated, as implications, that each relative quantity has two values - one in the longitudinal and the other in the transverse directions. As a consequence, we have found out the missing equations which are necessary to make Einstein’s theory of special relativity self-consistent and complete. Moreover, we use the geometric mean to get the mean value of the relative quantities. The justification of doing so is also demonstrated in this paper. Finally, in the appendix, we present the relativistic multiplication rules for the relative quantities like velocity, mass, time and length by a number. We also present the general rules for the product of two relative quantities of the same entity. Keywords: Relativistic addition and multiplication, velocity, mass, time, length, special relativity, missing equations, geometric mean.

1. INTRODUCTION

The relativistic addition of velocities using Lorentz-Einstein transformation1,2 is given by the well known formula

2

v1

vv

c

u

uuVr

(1)



where, Vr is the relative velocity, observed from an inertial reference frame S, of a body

moving with a speed u in another frame S'; when S' moves uniformly with speed v relative

to S and c is the speed of light. We have introduced the symbol to mean L-E addition.

This means that velocity v should be added to the velocity u by L-E addition )( and not

by Galilean addition (+). Now, if there is N number of equal velocity u to be added

relativistically, then

uNuuuuVr ............. (2)

where, for the L-E sum of N terms we have used the expression uN . In other words,

the symbol has been used for L-E multiplication.

The relativistic addition of velocities have also been derived without using the L-E

transformations but using thought experiments and the formulas that account for time

dilation and length contraction3,4, from the invariance5 of c and using the time dilation

formula6. We have used the formalism, presented in this paper, to find the relativistic

expression of momentum conservation law7. Further, in a recent paper8, we have shown

the wave representation of particle kinematics and the equivalence between continuous

and discrete time using the same. On the other hand, Mr. Ahmad9,10 has studied the

discrete and continuous representations of the same motion employing this formalism.

The main objectives of this work are (a) to widen the scope of special relativity (to

accommodate quantum mechanics) by including some missing equations into Einstein’s

theory of SR and (b) to understand the role of the speed of light.

2. DERIVATION OF THE FORMALISM

Let us consider that the frame of reference S' moves along the X-axis with a uniform

velocity v relative to a stationary frame of reference S as shown in Fig. 1. There is a light

beam clock, with its two parallel mirrors placed horizontally along X-axis, in the frame of

reference S'. The clock traps a light pulse between two parallel mirrors that bounces off the

mirrors at perfectly regular intervals of time. The light pulse takes time t0/2 to travel from

one mirror to another. Suppose, initially the origins of S and S' are coincident.



Fig. 1: S (X, Y, Z) is a Stationary and S' (X', Y', Z') is moving frame of reference. M1', M2' are

the horizontally placed mirror positions, of a light beam clock, after time t0/2, with M1 and

M2 being their positions after time t0. The separation between the mirrors is l0. The solid

line with arrows represents the path of light beam as seen from S.

Then an observer in S will see that in time t0, the frame S' will move a distance (d) given in

terms of the path of light by

00000 v

2

v

22

v

2t

tcttctd

(3)

During the same time interval, the light pulse traverses a path (d') given by

2

vt

22

vt

2

0000 ctctd (4)

ccc

cc

d

d v

vv

vv

(5)

Multiplying both sides by c and rearranging the terms,

1v1

v1

1v1

v1

vv

c

c

c

c

cc

c (6)

Hence, we can conclude that a velocity can be represented as a fraction of c by the above

relation. Thus, the L – E law (Eq. 1) can be written as

ccu

ccuc

cc

ucV

v1

vvr

(7)

Hence, following Eq. (6), we can write

1v1

v1

1

1

1v-1

v1

1

1

c

c

cu

cu

c

c

cu

cu

cVr (8)

Therefore, for v = c

1/1

/1

1/1

/1

22

2

cu

cu

cu

cu

cuuuVr (9)

where, the symbol indicates L-E multiplication. Similarly, we can show that



11

1

11

1

N

N

cu

cu

cu

cu

cuN (10)

Where, N is a number. The above equation represents the L-E multiplication of the

velocity u by the number N. It is equivalent to the L-E sum of N number of equal velocity

u. It has some advantages over the conventional form as follows. Suppose there is N

number of equal velocities to be added relativistically. If the conventional L-E law is used

for this purpose, N – 1 number of steps is needed to get the final result. But the operation

becomes cumbersome after 3 or 4 steps. Whereas, using the present form, the final result

can be obtained in just a single step even for large values of N. The conventional form can

be found suitable for certain cases, whereas, the present form can be used to uncover

different aspects of physical phenomena. As a result, the domain of relativity is expected

to be expanded beyond its horizon.

The above equation can also be written as

NN

NN

cucu

cucucuN

/1/1

/1/1

(11)

Hence, in the classical limit (u << c)

NucNucNu

cNucNucuN

/1/1

/1/1 (12)

which is the Galilean multiplication of the velocity u by the number N.

3. PROPERTIES OF uN

We would like to verify if the expression for uN , as given by Eq. (10), correctly

represents the L-E sum given by Eq. (2). The correct representation has to have the

following properties.

00 u (13)

uu 1 (14)

unmunum )()()( (15)

)v()v()( ummum (16)

umnunm (17)

Where, m and n are any numbers and u and v are velocities. For example, Eq. (16) can be

written, following Eq. (10), as

1/v1

/v1

1/v1

/v1

1/1

/1

1/1

/1

)v()(

m

m

m

m

c

c

c

c

c

cu

cu

cu

cu

cmum (18)



)v(

1/v1

/v1

/1

/1

1/v1

/v1

/1

/1

um

c

c

cu

cu

c

c

cu

cu

cmm

mm

(19)

Thus, it can be shown that all conditions of Eqs. (13) – (17) are fulfilled. Hence, we can

conclude that the formalism given in Eq. (10) correctly represents uN .

4. RELATIVE LENGTH

As shown in Fig. 1, the length between the two mirrors is l0. Now in time t0, the light travels

twice between the mirrors,

00 2lct (20)

or

c

lt 0

0

2 (21)

As observed by an observer in S, the distance (d+) traveled by light beam from mirror M1 to

M2 in the forward direction is

cct

d /v12

0 (22)

Again the distance (d-) traveled by the same beam from M2 back to M1 (i.e. in the backward

direction) is

cct

d /v12

0 (23)

Hence, the relative length (l) between the mirrors will be equal to the geometric mean

(justification is given in Section 6) of d+ and d- expressed as follows:

2

2

02

20 v

1v

12 c

lc

ctddl

(24)

Thus, the length is contracted in the longitudinal direction by the factor2

2v1

c .

5. RELATIVE TIME

Further, as observed by an observer in S, the time taken by the light beam (t+) to travel

from M1 to M2 (i.e. in the forward direction) is from Eq. (22),

ct

c

dt /v1

2

0

(25)

Again, the time taken by the same light beam (t-) in traveling from M2 back to M1 (i.e. in the

backward direction) is from Eq. (23),



ct

c

dt /v1

2

0

(26)

Hence, the relative time (t/2) taken by the light beam to travel from one mirror to other is the

geometric mean of t+ and t-.

2

20 v

122 c

ttt

t

(27)

2

2

0

v1

ctt (28)

where, t is the total relative time for the light beam to travel from M1 to M2 and back to M1.

The same relation can also be obtained from Eqs. (21) and (24) as

2

2

0

v1

2

ct

c

lt (29)

Thus, time is contracted in the longitudinal direction.

6. JUSTIFICATION OF USING GEOMETRIC MEAN FOR RELATIVE QUANTITIES:

Let us consider a different velocity u instead of v in Eq. (23), that is

cuct

d 12

0 (30)

Then, from Eqs. (22) and (30), the arithmetic average of d+ and d- is

cucct

dav v222

1 0 (31)

2

v1

2

0 cuct (32)

c

wct G

2

11

2

0 (33)

Where,

uwG v (34)

is the Galilean addition of velocities. However, we need relativistic addition which can be

achieved as follows. Let us take the geometric mean of d+ and d-:

21

0 1v12

cucct

dddgm (35)

2

1

2

0 vv1

2

c

u

cc

uct (36)

2

1

22

120

v1

v11v1

2

cu

u

ccu

ct (37)



2

1

2

120 1v1

2

c

wcu

ct r (38)

where,

2v1

vv

cu

uuwr

(39)

is the relativistic addition of v and –u according to the Lorentz – Einstein law. When v = u,

wG = wr = 0 and

2

0ctdav (40)

21

220 v12

cct

dgm (41)

Hence, we can conclude that geometric mean is relativistic and arithmetic average is

Galilean in nature.

7. IMPLICATIONS OF THE RESULTS

(i) Relative Time

However, according to Einstein’s theory of relativity2, time is dilated in the transverse

direction which can be derived by considering the light beam clock placed perpendicular to

the direction of motion. Let us denote it by tET (in the suffix, E stands for Einstinian relativity

and T for transverse), then it can be expressed as follows:

2

2

0

v1

c

ttET

(42)

where, t0 is the time interval during a complete round trip of a pulse in a stationary light beam

clock (proper time). Now, since Eq. (28) represents contraction of time in the longitudinal

direction, we will denote the relative time by tEL (L stands for longitudinal). Henceforth, all

relative quantities will be denoted with suffixes EL for longitudinal and ET for transverse

values. Then, Eq. (28) can be written as

2

2

0

v1

cttEL (43)

From the above two equations, we get 2

0ttt ETEL (44)

That is the product of the longitudinal and transverse relative times is equal to the square of

the proper time. The above equation also indicates that the proper time is an invariant

quantity and is equal to the geometric mean of the relative times.

(ii) Relative Length

Using Eq. (21) in the above equation, we can write



2

204

c

ltt ETEL (45)

Hence, using Eqs. (42) and (43), we obtain

2

20

22

0220

4

v1v1

c

l

c

tct

(46)

or

20

22

0220

cv1

2v1

2l

ctc

ct

(47)

or

20

22

0220

v1v1 l

c

lcl

(48)

or 20lll ETEL (49)

where,

22

0 v1 cllEL (50)

and

22

0

v1 c

llET

(51)

where, lEL and lET are longitudinal and transverse lengths respectively. Equation (50) indicates

that the length is contracted in the longitudinal direction as in Eq. (24). On the contrary, Eq.

(51) indicates that the length is dilated in the transverse direction. However, Eq. (49) shows

that the product of the longitudinal and transverse lengths is equal to the square of the length

at rest. It means that the length at rest is an invariant quantity and is equal to the geometric

mean of the relative lengths.

(iii) Relative velocity

Rearranging the terms, Eq. (46) can also be written as

22

0

0

220

02 v12

v1

2c

t

l

ct

lc (52)

Hence, using Eq. (20), we get

222

22v1

v1ccc

c

c

(53)

2ELETvv c (54)

where,



22ET

v1v

c

c

(55)

and

22EL v1v cc (56)

vET and vEL are the transverse and longitudinal velocities, respectively. It is clear from the

above equations, both of them become equal to the speed of light when v→0. However, for 0

< v < c, c > vEL > 0 and c < vET < ∞. That is, for increasing v, vEL decreases but vET increases

from c. That is vEL and vET change in opposite directions with increasing velocity. So that

for v → c, vEL→ 0 and vET→ ∞. Moreover, the product of these two velocities is equal to the

square of the speed of light. That is the speed of light is an invariant quantity, in conformity

with the postulate of special relativity, and is equal to the geometric mean of the relative

velocities.

(iv) Relative momentum and mass

Multiplying both sides of Eq. (53) by m02, we get

2022

022

0 v1v1

cmccmc

cm

(57)

or 20ppp ELET (58)

where,

cmp 00 (59)

22

0

v1 c

cmpET

(60)

and

220 v1 ccmpEL (61)

In the above equations, p0 is the momentum when v→0. pEL and pET are the momentums in the

longitudinal and transverse directions, respectively. It is clear from Eq. (58) that the product of

the transverse and longitudinal momentums is equal to the square of the momentum when

v→0. It means the momentum p0 is an invariant quantity and is equal to the geometric mean

of the relative momentums.

Moreover, from Eq. (57), we can write

20

220

22

0 v1v1

mcmc

m

(62)

or 20mmm ELET (63)

where,



22

0

v1 c

mmET

(64)

and

220 v1 cmmEL (65)

In the above equations, m0 is the rest mass; mET and mEL are relative masses in the transverse

and longitudinal directions, respectively. It should be pointed out here that mET is the relative

mass presented by Einstein in his theory of special relativity. Moreover, Eq. (63) shows that

the product of the relative masses is equal to the square of the rest mass. It means the rest

mass is an invariant quantity and is equal to the geometric mean of the relative masses.

The expressions for longitudinal time given by Eq. (43), transverse length given by Eq. (51),

Transverse velocity given by Eq. (55), longitudinal velocity given by Eq. (56) and longitudinal

mass given by Eq. (65), respectively, are the missing equations in Einstein’s theory of special

relativity. Further, the expressions for the invariance of time given by Eq. (44), the invariance

of length given by Eq. (49), the invariance of the speed of light given by Eq. (54) and the

invariance of mass given by Eq. (63) are also necessary to make the total set of equations self-

consistent. Thus, we conclude that these equations along with the existing ones make

Einstein’s theory of special relativity self consistent and complete.

The complete set of self consistent equations for the relative mass, time, length and

velocity in the case of Einstein’s theory of Special Relativity (SR) has been given in the

following Table 1. The table includes both the existing and missing equations of SR. For

each of the relative quantities, both the longitudinal and transverse values and the value of

their product are given. The relative values in the transverse and longitudinal directions

are denoted by the suffixes ET and EL, respectively.

Table 1: Equations of relative quantities in Einstein’s theory of special relativity.

Relative

Quantity Transverse Longitudinal Product

Mass 22

0

v1 c

mm

ET

22

0v1 cmm

EL

2

0mmm

ETEL

Time 22

0

v1 c

tt

ET

22

0v1 ctt

EL

2

0ttt

ETEL

Length 22

0

v1 c

ll

ET

22

0v1 cll

EL

2

0lll

ETEL

Velocity 22v1

vc

cET

22

ELv1v cc

2

ETElvv c

Where, the symbols have their usual meanings. The equations in yellow color are the

missing equations.



8. CONCLUSIONS

Through a thought experiment based on L-E law for the addition of velocities, we have

found:

(a) A relativistic rule for multiplication of a velocity by a number.

(b) That both the length and time contract in the longitudinal direction.

(c) Geometric mean is relativistic and arithmetic average is Galilean in nature.

Further, as implications of the results obtained, we have found:

(a) The relative time contracts in the longitudinal direction but dilates in the

transverse direction. Their product is equal to the square of the proper time.

(b) The relative length contracts in the longitudinal direction but dilates in the

transverse direction. Their product is equal to the square of the proper length.

(d) The relative mass increases in the transverse direction but decreases in the

longitudinal direction. Their product is equal to the square of the rest mass.

(e) The relative velocity decreases in the longitudinal direction but increases in the

transverse direction. Their product is equal to the square of the speed of light c.

REFERENCES

1H.A Lorentz, KNAW, Proceedings, Amsterdam, 6, 809 (1904). 2A. Einstein, Annalen der Physik, 17, 891 (1905). 3M. S. Greenwood, Am. J. Phys., 50, 1156 (1982). 4W. N. Mathews Jr., Am. J. Phys., 73, 45 (2005). 5N.D. Mermin, Am. J. Phys., 52, 1119 (1984). 6L. Sartori, Am. J. Phys., 63, 81 (1995). 7M. Ahmad and M.O.G. Talukder, Sent for publication in Phys. Essays (2011). 8M. Ahmad and M.O.G. Talukder, Phys. Essays, 24, 593 (2011). 9M. Ahmad, Phys. Essays. 22, 44 (2009) 10M. Ahmad, J. of Sc. Research 1, 270 (2009). DOI: 10.3329/jsr.v1i2.1875



APPENDIX

Multiplication Rules for the Relative Quantities:

A. Product Rule

Equations (44), (49), (54) and (63) can be expressed as the following general rule: 20XXX ETEL (A1)

or

100

X

X

X

X ETEL (A2)

where, X is any relative quantity with X0 being its value at rest; XEL and XET are its values in

the longitudinal and transverse directions, respectively.

B. Multiplication by a Number

(i) Relative Velocity

Putting u = vEL in Eq. (10), we get

1v1

v1

1v1

v1

v

EL

EL

EL

EL

EL

N

N

c

c

c

c

cN (B1)

Now, from Eq. (54), we can write

ET

EL

v

v c

c (B2)

Using the above value of vEL/c in Eq. (B1), we get

1v1

v1

1v1

v1

v

ET

ET

ET

ET

ET

N

N

c

c

c

c

cN (B3)

(ii) Relative length

From Eq. (20), we can write

0

02

t

lc (B4)

Putting this value of c in Eq. (59), we get

0

22

0

0EL

2v1

2v

t

lc

t

l EL (B5)



00

0

ELvlct

l

l

c

EL (B6)

Hence, from Eqs. (B1) and (B6), we can write

11

1

11

1

0EL

0EL

0EL

0EL

0

EL

N

N

ll

ll

ll

ll

l

lN (B7)

Similarly, it can be shown that c/vET = l0/lET. Putting this value in Eq. (B3), we can write

11

1

11

1

0

0

0

0

0

N

ET

ET

N

ET

ET

ET

ll

ll

ll

ll

l

lN (B8)

(c) Relative time

Equation (B5) can also be expressed as follows:

ETt

lc

t

l 022

0

0EL

2v1

2v (B9)

ETt

t

c

0ELv (B10)

Hence, from Eqs. (B1) and (B10), we can write

11

1

11

1

0

0

0

0

0

N

ET

ET

N

ET

ET

ET

tt

tt

tt

tt

t

tN (B11)

Similarly, it can be shown that c/vET = tEL/t0 and hence Eq. (B3) can be written as

11

1

11

1

0EL

0EL

0EL

0EL

0

EL

N

N

tt

tt

tt

tt

t

tN (B12)

(iv) Relative mass

Now, multiplying both sides of Eq. (56) by m0, we get

cmccmm EL 220EL0 v1v (B13)

0

ELv

m

m

c

EL (B14)



Hence, using Eq. (B14) in Eq. (B1), we can write

11

1

11

1

0

0

0

0

0

N

EL

EL

N

EL

EL

EL

mm

mm

mm

mm

m

mN (B15)

Similarly, it can be shown that c/vET = m0/mET and hence Eq. (B3) can be written as

11

1

11

1

0

0

0

0

0

N

Et

Et

N

Et

Et

ET

mm

mm

mm

mm

m

mN (B16)

Hence, the general expressions for the multiplications of relative quantities by any number N

can be written as:

11

1

11

1

0

0

0

0

0

N

EL

EL

N

EL

EL

EL

XX

XX

XX

XX

X

XN (B17)

and

11

1

11

1

0

0

0

0

0

N

ET

ET

N

ET

ET

ET

XX

XX

XX

XX

X

XN (B18)

where, X is any relative quantity with X0 being its value at rest; XEL, XET are its relative values

in the longitudinal and transverse directions, respectively.

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Spatial Environmental Impact on Land

Degradation in Bangladesh

Md. Mahmudur Rahman1, Md. Mostafizur Rahman

2, Tamanna Akter Tanu

3, &

Md. Masuder Rahman4

1Cartographer, Department of Geography, Environment and Urban Planning, Pabna University of

Science and Technology, Pabna, Bangladesh 2Lecturer, Department of Geography and Environmental Science, Begum Rokeya University, Rangpur,

Bangladesh 3&4M. Phil Research fellow, Department of Geography and Environmental Studies, University of

Rajshahi, Rajshahi, Bangladesh

ABSTRACT

Land is the terrestrial bio-productive system consisting of soil, vegetation and different ecological and hydrological processes that operate within the system. Land is very important for the human survival to obtain but it is being to degraded all over the world due to huge population pressure and human interventions. In Bangladesh enormous pressure on limited but vital land and soil resources are exerted, which strictly limits resilience of these resource. About 6.0 million ha or 40.43% of the total geographical area of Bangladesh is affected by land degradation. The physical signs of this degradation are observed as loss of soil fertility, loss of organic matter, accumulation of pollutants, physical, chemical, biological characteristics, drought, soil erosion due to surface runoff, soil acidification, river bank erosion, salinity of the soil, deforestation and removal of vegetation covers. Key words: Land Degradation, Environmental Impact, Bangladesh

INTRODUCTION

Land is the most prime element for the people in an agriculture based country like Bangladesh, a predominantly flat delta stretching from the Himalayan piedmont plan in the north to the coast of Bay of Bengal in the south. The landform of Bangladesh is grouped into three classes, viz, Floodplains (80%), Hills (12%) and Terrace (8%) and variations in land use are spectacular in these landforms (DoE, 2001). The annual cropping is the major land use pattern in floodplains, whereas mixed evergreen and deciduous forests are dominant in the hill. Land use is a dynamic process and changes in usage patterns are driven by agricultural and water demands, development of rural infrastructure, migration, urbanization and industrialization, to name a few. In terms of usages of lands, 17% of the total lands are forests land, 52% are cropped lands, 24% are rivers, wetlands and urban areas, 3% are fallow lands and remaining 4% are waste lands. A number of national estimates also show that 2.5% of the total land area in Bangladesh is used for industrial purposes (www.fao.org/ag).

http://www.fao.org/ag



Another the socio-economic factors, land use is determined by the environmental factors of climate in terms of seasonal variations of temperature, rainfall and humidity, hydrology in terms of depth and duration of seasonal inundation, soil drainage, dry-season soil moisture and availability of surface water for irrigation and other use. Additional hurdles to land development and crop cultivation comprise the risks of loss of land by bank erosion or burial by fresh alluvial deposition, sudden risks and onrush of flood water and the young nature of the alluvium/soil in the active and young floodplain areas and soil and water salinity, localized extreme acidity and toxicity of acid sulphate soils, scarcity of fresh water and occasional cyclones and storm surges in the coastal land (DoE, 2007). In Bangladesh land degradation has become a cause for serious concern to the people. About 6.0 million ha or 40.43% of the total geographical area of Bangladesh is affected by land degradation in varying degrees (Shoaib, 2007). This study describes the physical sings of this degradation are observed as loss of soil fertility, loss of organic matter, accumulation of pollutants, physical chemical, biological characteristics, droughts, soil erosion, due to the surface runoff, soil acidification, river bank erosion, soil salinity. This paper, therefore, emphasizes the spatial environmental impact on land degradation and vulnerabilities of all hazards in Bangladesh.

2. METHODOLOGY

In order to study the spatial environmental impact on land degradation in Bangladesh has been taken as a literature of the study. The study is extensively uses published and unpublished data of various books, journals and newspapers. Study related literatures provided a primary idea and information on this related terms. Where primary information survey was carried out through studying different study reports, journals, research papers, books, newspaper etc. Another the study is based on relevant secondary data collected from the sources census report as well as various governments, non governments organizations.

3. PHYSIOGRAPHY OF BANGLADESH

The geologic processes delineate above provide the basis for an understanding of the relief and topographic characteristics of Bangladesh. Apart from the hilly regions in the far northeast and southeast, most of the land is flat and covered by fertile alluvium spread over the land. The land is crisscrossed by a network of rivers with their numerous tributaries and distributaries. Owing to the flat nature of the terrain, the rivers generally have very low gradients 4-5 cm/km for the Ganges, 6-10 cm/km for the Brahmaputra and 3 cm/km for the Meghna ( Rasid and Pramanik, 1990).

4. ANALYSIS THE TREND OF LAND DEGRADATION IN BANGLADESH

The Net cropped area in Bangladesh was 8.08 million ha in 2000-2001 (BBS, 2001), the Net Cultivable area (NCA + Current fallow) in 1982-83 was 9.14 ha and in 1996-97 it was 8.14 million ha only. On average, the country is losing about 38.235 ha of cultivable land to non agriculture use. 2000-01, the per capita NCA was about 0.066 ha and an estimated population of 170 million in 2020, the NCA may be reduced to 7.5 million ha 7.5 million ha with per capita NCA of 0.044 ha only. However, due to high population growth, this allocation of land per capita is shrinking rapidly every year, making the resource base for agriculture, forest and wetlands more marginalized and vulnerable. This is mainly due to conversion of forest and agricultural land into urban and industrial uses and construction of roads and embankments.



Fig. 4 Trend of land degradation in Bangladesh if the graphical presentation

Source: BBS, 1981,95 , 01.

5. RESULT AND DISCUSSION

The following section focuses on the land degradation of Bangladesh in the study, it is tried to decide the causes of this degradation and second the spatial environmental impact was shown. 5.1. Population pressure on land use change Bangladesh is one the highest populated countries with growth rate of 1.8% (Shoaib, 2007). It is the mentioned that by the year 2020, population of Bangladesh will reach 170 million and density of 1118 per sq km and per capita land allocation as low as 0.6 ha, with possible loss of cultivable land to alternative uses like housing and urbanization. The pressure on the land use changed by rising population and effects of rising salinity, water, loss of soil fertility and high levels of erosion. SRDI (2004) estimated 0.1% of arable land per year converted to other use like settlements, roads, industries, brickfields and borrow pits based on interpretation of aerial photo of different years. Dispersed industrial growth and uncontrolled discharges of their untreated effluents into the nearby rivers deteriorate the quality of land, soil and water. Bangladesh has the highest density of road network 7.6 km/100 sq km, as the compared to India (1 km), China (2.7 km), and Pakistan (4.8 km) (Shoaib, 2007). Land fragmentation due to the crumbling of farm families is another issues which resulted from population boom and it is estimated that the land stood fragmented into about 12 million plots in 1990’s (Shoaib, 2007) and this figure is expected to be skyrocketing in future. Pressures on limited land resources stem from multifaceted issues relevant to land degradation. 5.2. Soil Salinity Saline soils due to strip of land of a few kilometers to 180 km width along the sea coast. However, reduction of fresh water flow from upper riparian areas and silting up to the Feeder Rivers enhance soil salinity in the coastal zone. During 1983 extension of saline area was 0.83 million ha which at present is estimated to be 1.02 million ha (SRDI, 2000). Bangladesh Water Development Board and SRDI are collecting and maintaining soil and

Trand of land degradaton in

Bangladesh

7.5

8

8.5

9

9.5

1981-82 1995-96 2000-01

year

Mil

lio

n i

n h

a



water saline that FAO has provided support to CEGIS for compiling, updating and interpretation of the salinity information. Water salinity level increased very rapidly in the year 2008 compared to reference salinity information of 1980s developed by MPO. Water salinity level has increase at most of the points in alarming rate over last 30 years, on average 172% Maximum increase of 1988 micromoles/cm is in Khulna region followed by 1442 micromoles/cm at Nalianla (Hadda). Salinity interruption has created a major problem in Khulna and Satkhira region in the south of Bangladesh. In a study done in 2000 it was revealed that 1.1 million ha of land are losing fertility because of salinity intrusion every year (DoE, 2007). A Comparative status of total saline area and area under different degrees of salinity in 1973 and 2000 if depicted in Figure 5.2 During the last three decades, about 0.17 million hectares of land was newly affected by various degrees of salinity, where substantial increase was fond in strongly (8.1-16.0 dS/m) and very strongly saline (>16 dS/m) classes (Shoaib, 2007).

Source: BBS, 1973, 2000 and SDRI, 2009. SRDI produced soil salinity data using the reference information of 1973. Large area has become salt affected over the last 35 years. More than 170,000 hectare has been affected in the 11 district, the situation has further aggravated in the year 2009. This is a very severe threat which largely affects productivity and livelihoods of the area (Karim at al., 1990). Salt- beds and shrimp cultivation have bearing on coastal soil degradation and change in landscape. Production of salt becomes more profitable and that enhance transformation of agricultural lands to salt-beds, which degrades the soil and makes future use of the land for crop production very difficult. Bangladesh experienced one of the worst cyclone-cum-tidal surges on 15 November 2007 during finalization of this paper, which has further falling downward the land resources in the south-western regions of Bangladesh. 5.3. Riverbank Erosion

Bangladesh has more than 700 rivers with their tributaries and distributaries of deltaic that are crisscrossed in the predominantly riverine country. However, 283 locations, 85 towns and growth centers along with 2400 km of riverbank line in Bangladesh are vulnerable to erosion. The total length of 22,155km (DoE, 2001) have become moribund because of siltation of river

Fig. 5.2 Soil Salinity status in 1973 and 2000

0

0.2

0.4

0.6

0.8

1

1.2

S 1

973

S 2

000

S1 1

973

S1 2

000

S2 1

973

S2 2

000

S3 1

973

S3 2

000

S4 1

973

S4 2

000

Years

Mil

lio

n h

a

Series1



beds, enhanced flood and river bank erosion, restricted navigation and water flows. Among these, riverbank erosion is a major issue. It is estimated that more than 100,000 people are displaced annually due to river bank erosion (Shoaib, 2007). River bank erosion is very serious hazard in Bangladesh with disastrous socioeconomic consequences. Hydraulic action in the form the sheer physical impact of flood waters in river channels is a major cause of erosion of the banks (Miah, 2004). Most of the rivers of Bangladesh flow through unconsolidated sediments of the GBM floodplain and delta, and the riverbanks are extremely susceptible to slumping or erosion by river current action. Riverbank erosion causes channel shifting creation of new channels during floods, bank slumping due to undercutting, and local scour from turbulence due to obstruction (Ahmad et al., 2001). Satellite image to the GBM rivers demonstrate varying properties of bank erosion and accretion in different years with an annual erosion rate of nearly 9,000 hectares of land ((Ahmad et al., 2001). Riverbank erosion /accretion along the different rivers for the period 1984-94 have been increased. Table 5.3 River bank erosion/accretion along the different rivers for the period 1984-93.

Name of the title Jamuna Ganges Padma Upper

Meghan

Lower

Meghna

Bank erosion

rate

Left 100 -20 38 7 66

Right 84 56 121 -9 182

Maximum bank

erosion rate(m/yr)

784 665 620 NA 1172

Bank erosion

( ha/year)

5020 2240 1800 48 1172

Bank accretion

(ha/year)

890 1010 233 49 402

Source: ISPAN, 1995. 5.4. Land slide

Hill areas or upper riparian areas are sensitive, as any anthropogenic disturbances there will create erosion, flooding and sedimentation in the lower regions. Large scale topsoil loss and landslides occur in the hilly region of south eastern Bangladesh. It is estimated that about 8,700 ha of area are being eroded annually (Shoaib, 1999). This region occupies about 12% geographical area of the country. This is concentrated in Chittagong occupying 76% very steep to steep sloping areas. Sloping areas of this region are not used with adequate conservation measures. Improper cultivation of Hill Slopes, Terrace Land and Piedmont Plains enhances topsoil loss. Shifting cultivation on the hills, locally known as ―Jhum‖ is a common practices the tribal communities in the greater CHT. Therefore, the soil quality has been degrading rapidly. SRDI measured soil loss from different slope classes in CHT under jhum cultivation, which ranges from 36 to 45 t/ha/y (Shoaib, 1999). In recent years, urbanization in these hilly areas also prompted hill-cutting, thus subjecting the surrounding areas to risks from landslides. Such landslides not only causes environmental havoc, but also cost human lives. The landslide that occurred in Chittagong in mid 2007 was a serious disaster for the poor residents settled at the foot of the hills and accounted for the loss of huge lives. 5.5. Agro-chemicals

Agricultural activity in Bangladesh is primary focused on the task of producing food crops for the growing population. Agricultural output can be increased through either one or both of the two approaches: (a) expansion of cropped area into new lands; and (b) intensification



of farming through increasing the yield per unit area (Rasheed S, 2008). Almost all cultivable lands in the country have already been brought under the plow, and newly emerging char lands (sandbars) and fast-shrinking dry season grazing grounds offer little scope for any significant expansion of cropped area (Brammer, 2002). The farmers of Bangladesh are intensification of cultivation in order to production. As a result, these pathways of intensification are multiple cropping, use high yielding diversity seeds, fertilizers along with pesticides and irrigation. Large amounts of pesticides, fungicides and herbicides are imported to keep crop production sustainable table 5.5. The scenario indicates that there is remarkable use of agrichemicals in agricultural production system and that poses as hazards to human health, fisheries, soil health and livestock. Table 5.5 Import of pesticides during the season

Year Tons Value (million taka)

1980-81 2274.04 202.29

1990-91 5122.00 642.67

2000-01 5655.00 1207.76

Source: Handbook of Agricultural statistics, 2004

5.6. DROUGHTS

Another climate change is Droughts, this hazard are natural occurrence their impacts are mitigated and their effects may be minimized provided. The consequence of drought can be as far reaching and disasters are the effect of a major flood. Bangladesh has a major drought when about 47% of the total area and 53% of the total population. Bangladesh has experience droughts a major magnitude in 1973, 1975, 1978, 1979, 1982, 1989, 1992, 1994 and 1995. Therefore, droughts of various intensities occur in all most parts of Bangladesh during the eight months from October to May.

6. CONCLUSION

Bangladesh is a small country in size inhabited by a large number of populations. High population remains the single most important determinate of resource and environmental degradation. Land is the most basic natural resource in the country, and despite the fact that the current land-person ratio in extremely unfavorable. Population increase through slowed in recent year, is still unacceptably high. It has increased on goods and services, and the turn, increased stresses on environmental resource. However, land and water are two of the most important natural resources of Bangladesh but over population due to land degradation. Among Bangladesh has responded to the issues of reversing the trend of land degradation by incorporating many activities.



BIBLIOGRAPHY

Ahmad, Q. K., et al., (2008). Ganges- Brahmaputra- Meghna Region: A framework for

Sustainable Development. The University Press Ltd., Dhaka.

Brammer, H. (2002). Land Use and Land Use Planning in Bangladesh, The University

Press Ltd., Dhaka.

BBS, (1981). Yearbook of Agricultural Statistics of Bangladesh. Bangladesh Bureau of

Statistics, Ministry of Planning, Government of Bangladesh, Dhaka.

BBS, (1995). Agricultural Statistics of Bangladesh: Bangladesh Bureau of Statistics,

Ministry of Planning, Government of Bangladesh, Dhaka.

BBS, (2001). Agricultural Statistics of Bangladesh: Bangladesh Bureau of Statistics,

Ministry of Planning, Government of Bangladesh, Dhaka.

DoE, (2001). State of the Environment Bangladesh: Ministry of Environment and Forests,

GOVT of the People Republic of Bangladesh.

Miah, M. M. (2004). Water Management in Bangladesh: From Vision to Action. Bangladesh

Water Partnership, Dhaka.

Shoaib, J. U. M. (2007). Land degradation including Resource Mobilization. Thematic

Report prepared under National Capacity Self-Assessment for Global

Environmental Management. IUCN Bangladesh (unpublished).

Shoaib, J. U. M. (1999). Restoration of Abandoned Jhum Annual Report. Soil Conservation

ans Watershed Management, Soil Research Development Institute, Bndarbon.

SRDI, (2000). Upazila Nirdeshika Database 1985-2000: Soil and Land Resource Information

System. Soil Research Institute.

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Important Deadlines for the Inaugural Issue a) Submission of Full Paper 10th February 2013 b) Reviewer’s Feedback and Notification of Full Acceptance 15th February 2013 c) Registration Deadline 20th February 2013 d) Expected to be in the press by the 1st week of March, 2013

Processing Fee for Regular Issue US$ 80 (Outside Bangladesh Author, except shipping) BDT 6000 (Bangladeshi Resident Author)

The journal is patronized by Asian Business Consortium (ABC). All authors of the ABR will be considered as ABC member. With regards, Editor, Asian Business Review

mailto:[email protected]

http://www.abrjournal.weebly.com/

http://abrjournal.weebly.com/

http://abrjournal.weebly.com/submission.html

http://abcreorg.weebly.com/

http://abcreorg.weebly.com/membership.html



UPCOMING

ABC JOURNAL OF SCIENTIFIC RESEARCH Aim and Scope ABC Journal of Scientific Research is a blind peer-reviewed international research journal which deals with applied as well as theoretical issues. The authors welcome papers in all the major issues including:

Research Article Review Article Scientific Commentaries Computer Science Technological Science Engineering Biology Chemistry Physics Mathematics Statistics Applied Business Studies Medical Studies Social Sciences Natural Sciences Agricultural Science Zoology Geology Short Communication All other Applied and Theoretical Scientific Research

Contact Information Paper submissions should be electronically in MS-Word form on the following email address [email protected].

Www.Abcjournals.Weebly.Com

mailto:[email protected]

http://abcjournals.weebly.com/



Why Work with ABC 1. Voluntary reviewers have complete authority to set the standards for the

acceptance of manuscripts; 2. Voluntary reviewers have complete authority to determine whether a

manuscript is accepted or not; 3. Voluntary reviewers have the right to revise the scope and policies of

their journals; 4. Voluntary reviewers pay a reduced fee for ABC publication; 5. ABC has its own marketing team. Editorial board/Voluntary review board

members are not required to solicit papers.

Asian Journal of Applied Science and Engineering (AJASE)

Documents

Transcript of Asian Journal of Applied Science and Engineering (AJASE)