Thesis Ergonomics

8/11/2019 Thesis Ergonomics

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Chapter 1

Introduction

1.1Justification

1.1.1 Hospital Bed in Bangladesh

Hospital bed is used in hospital and designed for patients and others in need of some form ofhealth care. Hospital beds and other similar types of beds are used not only in hospitals, but

in other health care facilities and settings, such as nursing homes, assisted living facilities,outpatient clinics, and in home health care. Every patient, regardless of care setting, deserves

a safe and comfortable sleeping and bed environment. Hospital bed needed to design in sucha way that both the patient and health care workers feel comfort, safe and convenience.

Improper design of medical bed is responsible for many types of psychological and physicalproblems like back pain and it hampers to sleep. In the developed countries middle-edged

people who suffer from backache often report that their backache started when they were intheir twenties, the period when many of them are still attending university (Watson et al.

2002). Our health is directly influenced by the way we sleep. It is a common truth that quality

of life depends on quality of sleep. An adequate comfortable sleep can significantly extend

your life. Improper sleep may cause a lot of problems and even diseases like osteochndrosis,

radiculities, arthritis, blood supply disturbance, insomnia, allergy, asthma, etc.

Hospital beds are different from other beds, and Bangladeshi hospital beds are different fromother hospital beds. Here, hospital beds are reffered as beds to people. In some hospitals

one hundred beds are placed in rows with a gap of only a few feet and without any bedcurtains, the patient can hardly maintain any space for themselves. Even a bed sheet or a

mattress placed on the floor has come to be considered a bed. The distance between the bedsis generally four or five feet at the most. The patients who get a corner bed, with a wall on

one side get too less space. The extra patients are placed on the floor with only a mattress or

even just a sheet to lie on. Patients considered their hospital bed as a kind of prison.

Moreover, attending relatives are occupants of the patients hospital bed. Because therelatives are integral, albeit informal, part of hospital organization the hospital authorities

allow the relatives to use hospital facilities including beds.

Beds are generally a private space, but they become public in hospital ward that is certainly

true in a Bangladeshi hospital ward. This is to note that the hospital is a public one wheremainly poorer people of the community go for treatment, which is more or less free of

charge. Without a doubt, the bed takes on a specific personality in a Bangladeshi hospital. Itreflects the feature of Bangladeshi society. It shows the proverty and social inequality in thecountry and the crucial role of family members in an individuals life. An ordinary piece of

furniture, the bed, has become a portrait of a society at large.

There has more variations in the design of hospital bed and no one is designed with

considering anthropometric data of Bangladesh. There has a less number of Industrial or

Human Factor Engineer in our country. As a result, the concept of ergonomics or human

factor engineering is poor in Industry. For this reason, Industries cannot imagine that

ergonomics approach can change their productivity and mental satisfaction dramatically.


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1.1.2 Ergonomics

The word "Ergonomics" comes from two Greek words "ergon," meaning work, and "nomos"

meaning laws (Bridger 1995). Ergonomics is the interaction among man, machine and

environment which focuses on the interactions between the works demand and worker

capabilities. It is the study of designing or arranging workplaces, products and systemconcerned with finding ways to keep people safe, comfortable, and productive while they

perform tasks at workstation and home. It is concerned with the design of systems in which

people carry out work. So that it fits the people who use them.

The practice of ergonomics requires that knowledge about human anatomy, physiology, and

psychology be applied to the design of work systems. Particular emphasis is placed on thedesign of the human-machine interface to ensure increased safety and usability of equipment

and the removal of harmful stressors. There are two ways in which ergonomics has an impactupon systems design in practice. First many ergonomists work in research organizations or

universities and carry out basic research to discover the characteristic of people that need to

be allowed for in design. This research often leads, directly and indirectly, to the drafting ofstandards, legislation, and design guidelines. Second, many ergonomists work in a

consultancy capacity either privately or in an organization. They work as a part of a design

team and contribute their knowledge to the design of the human-machine interactions in work

systems. This work often involves the application of standards, guidelines, and knowledge to

specify particular characteristics of the system.

Ergonomics aims to ensure that human needs for safe and efficient working are met in the

design of work systems. Ergonomics come about as a consequence of the design and

operational problems presented by the new work systems which have involved with the

advance of technology. It owes its development to the same historical processes which give

rise to other work system disciplines such as industrial engineering and occupationalmedicine.

Modern ergonomics contributes to the design and evaluation of work systems and products.Unlike the earlier times, when an engineer designed a whole machine or product, design is a

team effort nowadays. The ergonomists usually has an important role to play both theconceptual phase and in detailed design as well as in prototyping and the evaluation of

existing products and facilities. Modern ergonomics contributes in a number of ways to thedesign of work system. These activities should be seen as an integral part of the design and

management of systems rather than as optional extras.

The design of hospital bed should not be dependent on the esthetic views consideration but

also should be dependent on the different dimensions of users body structure and postures.So the size and dimension of hospital bed will be different for people live in different region

as human body dimension varies with region to region. Not only hospital bed, any furniture

and work place should be designed with considering ergonomics.

1.1.3 Anthropometry

Anthropometry is one of the basic parts of ergonomics that refers to the measurement of

human body. It is derived from the Greek words anthropos means man and metronmeans measure (Bridger 1995). Anthropometric data are used in ergonomics to specify the

physical dimensions of workspaces, equipment, furniture and clothing to fit the task to the

man (Grandjean 1980) and to ensure that the physical mistakes between the dimensions ofequipment and products and the corresponding user dimensions are avoided.


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Anthropometry involves the systematic measurement of the physical properties of the humanbody, primarily dimensional descriptors of body size and shape. Anthropologist have been

measuring humans for hundreds of years, but for only the last 50years or so have thedimensions been used in an organized fashion to improve the design and sizing of the things

we use in everyday life (Bhattacharya & McGlothlin 1996). Often the problem with the

application of anthropometry to a design problem will be the lack of certain necessarymeasurements or the need to accommodate a wide range in size and shape variability into a

single, often inflexible design. Applied anthropometry-that is, the use of anthropometric data

in the design and construction of a wide variety of items from clothing to spacecraft-is a

relatively new discipline whose practitioners are still learning to cope with the exponential

character of technology and its impact on the kinds of information needed to describe the

physical and biological characteristics of our species. It grew out of physical anthropology,

which traditionally studies body size and function with the goal of resolving our ancestry and

identifying the existing varieties of Homo sapiens.

The natural variation of human populations has implications for the way almost all products

and devices are designed. Anthropometric data can be used to optimize the dimensions of adiverse range of items-the length of toothbrush handles, the depth and diameter of screwtops

on jars and bottles, the size of tools in tool kits supplied with automobiles, medical tools and

equipments and almost all manual controls, such as those that are found on television,

videocassette recorders, radios etc.

1.1.4 Hospital Bed Parameters Related to Anthropometric Measurements.

1.1.4.1 Bed Length

The bed length is the horizontal distance between two remotest edges of the bed surface.Users want to accommodate their full body in the bed with average 20cm clearance. So,

mismatch occurs when the bed length is less than Stature + 20 cm clearance (Hossain &Ahmed 2010).

Figure 1.1: Vertical grip reach and stature


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1.1.4.2 Bed Width

The bed width is the horizontal distance between two nearest but opposite edges of the bed

surface. The bed the mismatch situation has been considered to be happened when the bed

width is less than Elbow Span + 10 cm clearance (Hossain & Ahmed 2010).

Figure 1.2: Elbow span

1.1.4.3 Bed Height

The bed height is the vertical distance from the floor to the highest point on the seat of the

bed. A mismatch of popliteal and seat height was defined as any seat height that is either>95% or


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1.1.4.4 Bed Stand Height

The bed stand height is the vertical distance from the floor to the highest point of the

mosquito stand of the bed. So, the mismatch occurs when the Bed Stand height is greater than

the Overhead Grip Reach (Standing).

1.2 Methods Used For Mathematical Calculation

Chi-square distribution

Analytic Hierarchy Process (AHP)

Regression Analysis

1.2.1 Chi-square distribution

The following information about chi square distribution is given from Wikipedia, the free

encyclopedia. (http://en.wikipedia.org/wiki/Chi-square_distribution).

Inprobability theory andstatistics, the chi-square distribution(also chi-squaredor-

distribution) with kdegrees of freedom is the distribution of a sum of the squares

of kindependentstandard normal random variables. It is one of the most widely

usedprobability distributions ininferential statistics, e.g., inhypothesis testing or in

construction ofconfidence intervals.When there is a need to contrast it with the non-central

chi-square distribution, this distribution is sometimes called the central chi-square

distribution.

The chi-square distribution is used in the commonchi-square tests for goodness of an

observed distribution to a theoretical one, the independence of two criteria of classification

ofqualitative data, and in confidence estimation for a populationstandard deviation of a

normal distribution from a sample standard deviation. Many other statistical tests also use this

distribution, likeFriedman's analysis of variance by ranks.

The chi-square distribution is a special case of thegamma distribution.

1.2.1.1 Definition

IfZ1...Zkareindependent,standard normal random variables, then the sum of their squares,

is distributed according to the chi-square distributionwith k degrees of freedom. This is

usually denoted as

Q ~ 2(k) or Q ~ k2

The chi-square distribution has one parameter: k(also denoted as ); a positive integer that

specifies the number ofdegrees of freedom
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1.2.1.2 Statistic of chi square distribution:

The statistic also can be written as- (oi ei)

2/ei (i=1 to)

Where

Xi=oi = observed frequency

i= ei= expected frequency

1.2.1.3 Characteristics curves

Figure 1.4: probability density function (pdf) of chi square distribution

Figure 1.5: cumulative distribution (cdf) function of chi square distribution

Probabilitydensityfunctionf(x)

x

CumulativeProbabilityF

(x)

x
http://en.wikipedia.org/wiki/File:Chi-square_distributionCDF.svghttp://en.wikipedia.org/wiki/File:Chi-square_distributionPDF.svghttp://en.wikipedia.org/wiki/File:Chi-square_distributionCDF.svghttp://en.wikipedia.org/wiki/File:Chi-square_distributionPDF.svg


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Table 1.1: characteristics of chi square distribution

notation:or

parameters: kN1degrees of freedomsupport: x[0, +)

pdf:

cdf:

mean: k

median:

mode: max{k2, 0}variance: 2k

skewness:

ex.kurtosis: 12/kentropy:

mgf: (1 2t) for t < cf: (1 2it)

1.2.2 Analytic Hierarchy Process (AHP)

The Analytic Hierarchy Process (AHP) is systematic approach for selecting alternatives.

People deal with complex decisions- rather than prescribing a "correct" decision, the AHP

helps people to determine one. Based on mathematics and human psychology, it was

developed by Thomas L. Saaty in the 1970s and has been extensively studied and refined

since then. Analytical Hierarchical Process (AHP) is a decision-making method for

prioritizing alternatives when multiple criteria must be considered and allows the decision

maker to structure complex problems in the form of a hierarchy, or a set of integrated levels.

A hierarchy is a system of ranking and organizing people, things, ideas, etc., where each

element of the system, except for the top one, is subordinate to one or more other elements.

Human organizations are often structured as hierarchies, where the hierarchical system is
http://en.wikipedia.org/wiki/Support_(mathematics)http://en.wikipedia.org/wiki/Probability_density_functionhttp://en.wikipedia.org/wiki/Cumulative_distribution_functionhttp://en.wikipedia.org/wiki/Expected_valuehttp://en.wikipedia.org/wiki/Medianhttp://en.wikipedia.org/wiki/Mode_(statistics)http://en.wikipedia.org/wiki/Variancehttp://en.wikipedia.org/wiki/Skewnesshttp://en.wikipedia.org/wiki/Excess_kurtosishttp://en.wikipedia.org/wiki/Information_entropyhttp://en.wikipedia.org/wiki/Moment-generating_functionhttp://en.wikipedia.org/wiki/Characteristic_function_(probability_theory)http://en.wikipedia.org/wiki/MCDAhttp://en.wikipedia.org/wiki/Mathematicshttp://en.wikipedia.org/wiki/Psychologyhttp://en.wikipedia.org/wiki/Thomas_L._Saatyhttp://en.wikipedia.org/wiki/Thomas_L._Saatyhttp://en.wikipedia.org/wiki/Psychologyhttp://en.wikipedia.org/wiki/Mathematicshttp://en.wikipedia.org/wiki/MCDAhttp://en.wikipedia.org/wiki/Characteristic_function_(probability_theory)http://en.wikipedia.org/wiki/Moment-generating_functionhttp://en.wikipedia.org/wiki/Information_entropyhttp://en.wikipedia.org/wiki/Excess_kurtosishttp://en.wikipedia.org/wiki/Skewnesshttp://en.wikipedia.org/wiki/Variancehttp://en.wikipedia.org/wiki/Mode_(statistics)http://en.wikipedia.org/wiki/Medianhttp://en.wikipedia.org/wiki/Expected_valuehttp://en.wikipedia.org/wiki/Cumulative_distribution_functionhttp://en.wikipedia.org/wiki/Probability_density_functionhttp://en.wikipedia.org/wiki/Support_(mathematics)


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used for assigning responsibilities, exercising leadership, and facilitating communication.

When we approach a complex decision problem, we can use a hierarchy to integrate large

amounts of information into our understanding of the situation. As we build this information

structure, we form a better and better picture of the problem as a whole.

Table 1.2:Level of preference weight

Level of

preference

weights

Definition Explanation

1 Equally Preferred Two activities contribute equally to the objective

3 ModeratelyExperience and judgment slightly favor one activity

over another

5 Strong importanceExperience and judgment strongly or essentially

favor one activity over another

7Noticeable

dominance

An activity is strongly favored over another and its

dominance demonstrated in practice

9 Extreme importanceThe evidence favoring one activity over another is of

the highest degree possible of affirmation

2,4,6,8 Intermediate valuesUsed to represent compromise between the

preferences listed above

Reciprocals Reciprocals for inverse comparison

1.2.3 Regression analysis:

Regression analysis is the focus on the relationship between a dependent variable and one or

more independent variable .Regression analysis helps one understand how the typical value

of the dependent variable changes when any one of the independent variable is varied, while

the other independent variables are held fixed. Most commonly, regression analysis estimates

the conditional expectation of the dependent variable given the impendent variable.

Regression analysis carried out the various techniques and developed the large body. A

simple liner regression technique is one of them. Simple linear regression is a technique in

parametric statistics thats commonly used for analyzing mean response of a variable Ywhich chances according to the magnitude of an intervention variable X. It forms the basis of

the one of the more important forms of inferential statistical analysis. In regression analysis

there is usually the independent variable and a dependent or response variable.

The relationship between two variables is best observed by means of a scatter plot. Then astraight line is drawn which would provide the best estimate of the observed trend. In other


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word, the line describes the relationship in the best possible manner. Even then for any given

value of X there is variability in the values of Y. this is because of the inherent variability

between individuals. The line drawn is therefore the line of means. Thus, it expresses the

mean of all values of Y corresponding to a given value of X.

Y-Axis

Figure 1.3: The regression line

Where the line of means cuts the Y-axis we get the intercept. The intercept is the value of Y

corresponding to X=0. Its units are the units of the Y variable. The line has a slope. The slope

measures the change in the value of Y corresponding to a unit change in the value of X.

Now it is clear that the line of means is an important parameter, its mathematical

representation Y= a + b X is called the regression equation, and a & b are the regression

coefficients.

1.2.4 One sided confidence bonds

The confidence intervals and resulting confidence bounds discussed thus far are two-sided in

nature (i.e., both upper and lower bounds are given). However, there are many applications in

which only one bound is sought. For example, if the measurement of interest is strength, the

engineer receives more information from a lower bound only. This bound communicates theworst case scenario. On the hand, if the measurement is something for which a relativelylarge value of is not profitable or desirable, then an upper confidence bound is of interest.

An example would be a case in which inference need to be made concerning the mean

mercury composition in a river. An upper bound is very informative in this case. One-sided

confidence bounds are developed in the same fashion as two-sided intervals. However, the is

a one-sided probability statement that makes use of the central limit theorem

P ( )=1-

One can then manipulate the probability statement much like before and obtain

P (>X-z/n) =1-

Slope

Intercept

X- Axis


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Similar manipulation of P (>-z) =1-

P (


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Chapter 2

Literature Review

Chou & Haiao (2005) have used two-dimensional anthropometric data for developing an

electric scooter in Taiwan. The developed electric scooter resulted in a significant

improvement in its appearance and ergonomic performance. The hierarchical estimation

method was applied to 60 anthropometric variables by using the 1988 US Army

anthropometric survey data and used to design an occupant package layout in a passenger car

(You & Ryu 2005).In 2006 Sebo et al have collected anthropometric data that were

performed by 12 primary care physicians on 24 adult volunteers in Geneva, Switzerland and

that was published in 2008.

Anthropometric data must contain at least some valuable information about certain aspect ofwelfare if growth reflects a persons diet and health. Cvrcek (2006) have explained that theheight and weight variation of adolescentboysexhibit a pattern that is inconsistent with thatfor a normal healthy population.

For ergonomic product design with better safety, comfort and health consideration three-

dimensional anthropometry is very important as it gather rich information. Chang et al.

(2007) have used three-dimensional anthropometric measurements that offer much more

surface information than traditional dimension measurement and proposed methods for low

cost portable hand-hell laser scanner along with a piece of glass used as a hand support to

reduce scanning shadow areas.

Engineering design is a strong determinant of workplace ergonomics. A survey among 680

engineers in 20 Danish enterprises indicated that engineers are not aware that they influencethe work environment of other people (Broberg 2007). Ergonomics had a low rating among

engineers, perhaps because neither management nor safety organizations expressed any

expectations in that area. The study further indicated that the effects of ergonomics training in

engineering schools were very limited.

The anthropometric measurement can be used as a basis for the design of workstations and

personal protective equipments that can make work environments safer and more users

friendly. Currently, there is increasing demand for this kind of information among those who

develop measures to prevent occupational injuries and increase the level of satisfaction.

Anthropometric measurements among 1805 Filipino workers in 31 manufacturing industries

showed data for standing, sitting, hand and foot dimensions, breadth and circumference ofvarious body part and grip strength that was the first ever comprehensive anthropometric

measurement of Filipino manufacturing workers in the country which is seen as a significant

contribution to the Filipino labor force who are increasingly employed by both domestic and

foreign multinationals and was published in 2007 (Pardo-Lu 2007). This study helps Filipino

working population for the economic design of workstations, personal protective equipments,tools, furniture and interface systems that aid in providing a safer, effective, more productive

and user friendly workplace.

Das, Shikdar & Winters (2007) demonstrated the beneficial effect of a combined work designand ergonomics approach, specially for the redesign of a workstation for a repetitive drill

press operation that increase both the production output and operator satisfaction. The result


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Braking and steering-assistance features of hospital bed have direct effects on task efficiency

and physical demand. Thus appropriate selection of specific designs able to improve

productivity and contribute to a reduction in work related musculoskeletal disorders risk

among healthcare workers. Kim et al (2009) have done a repeated measure experimental

study considering work related musculoskeletal disorders aimed to increase effectiveness ofhospital bed design features (brake pedal location and steering-assistance) in terms of

physical demands and usability during brake engagement and patient transportation tasks.

Iseri & Arslan (2009) have done a large survey of 4205 civilians (2263 males and 1942

female) in the year of 2007 to estimate the anthropometric characteristic of the Turkish

population by geographic region, age and gender which showed 37 measurements that are

commonly used in industry.

Husein et al (2010) have studied on facial anthropometry and aesthetic measurements to

compare Indian American women with North American white women. In this study the

researchers obtains 30 anthropometric measurements of 102 Indian American women and theresult showed significant difference in 25 of 30 facial measurements.

Laios & Giannatsis (2010) have employed virtual modeling technique and the method of

principle component analysis for ergonomic evaluation and redesign of children bicyclesbased on anthropometric data. In Greece the redesigned bicycles are now in full Production

and distribution is underway in many commercial outlets as proper fitting increases cyclingperformance, efficiency, and comfort and injury prevention.

Unsafe medical care leads to the suffering of millions of patients every year. Human Factors

and Ergonomics (HFE) is that scientific discipline which provides unique approach for

examining complex socio-technical systems. System approach, roles and methods of humanfactors and ergonomics have been studied by Carayon & Buckle (2010).

The system approach carefully developed by human factors and ergonomics specialists over

the past 50 years has a vital role to play in addressing healthcare challenges (Carayon &

Buckle 2010).

Hossain & Ahmed (2010) present 36 linear and static anthropometric dimensions and weight

of 88 male students living in three residential halls of Bangladesh University of Engineering

and Technology (BUET) for the design of five mostly used residential hall furniture (Bed,

Chair, Desk table, Book shelf and Locker). They showed the different percentages of

mismatches between furniture dimensions and corresponding body dimensions of individualusers.

Anthropometric data varies from region to region. Chuan, Hartono and Kumar (2010) werecollected anthropometric data of the Singaporean and Indonesian populations. The data were

mainly from university students. In total, 245 male and 132 female subjects from Indonesiaand 206 male and 109 female subjects from Singapore were measured. This study used 36

measurement dimensions. The authors made a comparison with previous anthropometric data

collected in 1990 of over a thousand Singaporeans. Statistical analysis showed that

Singaporeans both male and female tend to have larger dimensions than Indonesians in

general. In addition, the data reveal the current sample to be significantly larger on more than

50 percent of the dimension measured, for both males and females.


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Hafizi et al. (2010) have run a large anthropometric study on primary school children in Iranthat explained negative impact on human health if the use of furniture fails to fulfill

anthropometric data of its users. Gathering data about anthropometric dimensions areimportant as anthropometric data can change by time. In many communities anthropometric

data have been measured especially among school, college and university students. Study was

designed to obtain anthropometric dimensions of Iranian children aged 7-11 years and datawere obtained on 2030 primary school students (1015 males and 1015 females) in Yazd of

Iran. Study showed a descriptive statistics as well as key percentiles for 17 static

anthropometric data. The result showed some difference in anthropometric data with other

studies and significant gender differences in some dimensions as well. In order to create a

data bank for furniture design a study was run in Iran which measured anthropometric

dimensions of Iranian university students (Mirmohammadi et al. 2011). They measured 20

anthropometric dimensions of 911 university students (475 males and 436 females), aged 18-

25 years, that showed a significant difference between anthropometric dimensions of their

populations with others population. Except for buttock-knee all dimensions measured were

significantly different between two genders.

Hedge, James & Pavlovic-Veselinovic (2011) have optimized the implementation of

healthcare information technology considering risk of work related musculoskeletal disorders

in ways that will benefit user performance while minimizing their injury risks.

In the patient transportation study, the use of a steering lock reduced the number of

adjustments and decreased perceived physical demands during bed maneuvering.

Additionally, the adjustable push height reduced shoulder moments during an in-room bed

start-up task. The contour feature reduced patient sliding distance with repeated bed

raising/lowering, which can potentially reduce the demands placed on healthcare workers toreposition them. Metha et al. (2011) have suggested that proactive ergonomic considerations

in hospital bed design can reduce physical demands placed on healthcare workers.

International Ergonomics Association Technical Committee has been formed due to theconcern of increasing prevalence and role of information and technology in the lives of

children as well as the incident of back pain and heavy loads children carry in back packs(Bennett& Tien 2012). A survey was sent to Ergonomics for Children and Educational

Environments to describe a cross-section of international efforts to address the health and thefuture of children. It is possible to analyze and predict with an applied ergonomics that is

sensitive to the social complexities of workplace, including power, gender, hierarchy and

fuzzy system boundaries (Dekker 2012).

Widanarko et al. (2011) have described the prevalence of musculoskeletal symptoms in NewZealand where a sample of 3003 men and women aged 20-64 were randomly selected.

Musculoskeletal symptoms experienced during 12 months in 10 body regions were assessed

in telephone interviews using a modified version of the Nordic Musculoskeletal

Questionnaires. The highest prevalence was for low back (54%), neck (43%), and shoulder

(42%). Females reported a statically significantly higher prevalence of musculoskeletal

symptoms in the neck, shoulder, wrist/hands, upper back and hips/thighs/buttocks regions

compared to males while males reported more symptoms of elbows, low back and knees.

There were no statistically significant differences in prevalence among age groups.

Dianat et al. (2012) have evaluated the potential mismatch between classroom furniture

dimensions and anthropometric characteristics of 978 Iranian high school students (498 girls,


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480 boys), aged 15 to 18 years. The mismatch was varied between the high-school gradelevels and between genders, indicated their special requirements and possible problems.

In Bangladesh the use of ergonomics is very fewer in hospital and others workplace. The

objectives of this study is to show the relationship with physical demand (back pain, fatigue,

blood circulation problem, comfort and sleep) with anthropometric factors for hospital bed

and to build an anthropometric database for Bangladeshi patient to find correlation among

some pairs of these anthropometric factors.

2.1 Objectives

The objectives of this thesis are:

1. To show the relationship of physical demand (back pain, fatigue, blood circulationproblem, comfort and sleep) with anthropometric factors for normal hospital bed (Stature,

Elbow span, Political Height, Vertical grip reach) in Bangladesh.

2. To build an anthropometric database for Bangladeshi patient and redesign hospital bed

based on anthropometric data.

2.2 Methodology

The goal of the thesis was to find out the major WMSDs such as back pain, fatigue, blood

circulation problem, sleep and comfort .The hospital bed are responsible for above the

problem and risk factors. The anthropometries parameter of the human dimension isresponsible for WMSDs problem. The dimension of the hospital bed should be proper design.

In doing so the steps we have followed are shown in flows chart below:


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Chapter 3

Case Study & Data Collection

The objective of case study is to perform the steps required to meet the thesis goal. For that,

several steps had been taken. A short list of the steps is shown below:

The steps have been taken are:

At first, we have prepared some questionnaires for doctors and patients. Then we have visited

Rajshahi Medical Collage Hospital to collect data from doctors and patients. We haveanalyzed data after the answer of the questionnaires had taken. After that anthropometric data

of students have collected from Rajshahi University of engineering and Technology (RUET).Finally, anthropometric data have analyzed and appropriate methods have used for

mathematical calculations.

To collect data we have visited Rajshahi Medical College & Hospital, Rajshahi, Bangladesh.

A short description on Rajshahi Medical College is given below.

Rajshahi Medical College & Hospital, located in Rajshahi, Bangladesh which is affiliatedwith the Rajshahi University. It was established in 1958, the second such institution in

erstwhile East Pakistan after Dhaka Medical College. It has a large hospital that is centralprovider for a advanced healthcare in the northern part of Bangladesh. It admits 175 students

every year for its M.B.B.S. program. Its dental unit admits a further 50 students. Students areadmitted in these programs after high school and get a gegree after 5 years of study and 1

year internship in the Government owned public hospital.

A handful number of enthusiastic and philanthropic people started a Medical School inRajshahi city in 1954. A four year course was started leading to diploma called LMF

(Licentiate of Medical Faculty) offered by the State Medical Faculty, Dhaka. A total of eightystudents were admitted in the very first year of its inception. In 1954, the then East Pakistan

Government converted it into a government Institute, Rajshahi Medical School. Later on, the

government decided to start a five year course leading to MBBS (Bachelor of Medicine and

Bachelor of Surgery) degree and as such in 1958 Rajshahi Medical School emerged as

Rajshahi Medical College. At the beginning, the Medical College was housed in a small

building of the Barendra Museum. It was later shifted to the present college building. Forty

two native and two foreign students were admitted in the first batch.

Since then, the college has been continuing its steady progress. The number of admittedstudents is now increased to 175 which is equal in 8 old government medical colleges of

Bangladesh. Foreign students of SAARC countries are being admitted in this Institution

every year. Other hospitals situated in the city like Infectious Disease Hospital founded in

1962, Hospital for Tuberculosis and Chest Diseases founded in 1966, Leprosy Control Center

founded in 1968 are all affiliated with this college. A Nuclear Medicine Center was also

established within the campus in 1970. Following the war of liberation in 1971, the Medical

College and hospital have made considerable improvements in many aspects such as

extension of the college buildings, student's accommodation, number of hospital beds, and

establishment of a modern Auditorium etc. There has been addition of new departments like

Coronary Care Unit, Nephrology, Neurosurgery, Radiotherapy and Gastroenterology.


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Recently the hospital is equipped with CT scan, MRI, angiogram and renal haemodialysis

machine. There have been a few recent additions in the College too like establishment of a

beautiful mosque at the college premises, modernization and beautification of college main

gate and premises, extension of the conference room with modern audio-visual facilities. At

present besides undergraduate MBBS and BDS courses, postgraduate MD, MS, M.Phil, MPHand Diploma degrees are being awarded in 18 disciplines at Rajshahi Medical College.

After all of these there have a lot of problems in Rajshahi Medical College. The hospital beds

and other furnitures are not designed considering ergonomics and anthropometric data ofBangladeshi people. As a result patient suffers a lot of problems in times of having medical

service. Number of beds also less than the number of patients coming every day. And extra

patients are takes place on the floor which is also considered as beds. So, solving these

problems is very important for patient safety, comfort and proper service.

For this article, I have kept the Chinese proverb in mind, A picture is more powerful than athousand words. The figure expresses the present condition of Rajshahi Medical College.

Figure 3.1: Rajshahi Medical College & Hospital


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3.1 Rajshahi University of Engineering and Technology (RUET)

Rajshahi University of Engineering and Technologyformerly known as BIT, Rajshahi, is the

second oldest engineering university in Bangladesh.It was founded in 1964 as a faculty of

Engineering under the University of Rajshahi providing four years Bachelor degree in Civil,

Electrical and Electronic, Electronics and Telecommunication Engineering, Mechanical

Engineering and Industrial and Production Engineering, Computer Science and Engineering,

Glass and Ceramic Engineering, Urbanization & Regional Planning. It is widely reputed as

one of the best engineering universities in Bangladesh. About 2000 students are enrolled in

Undergraduate and Postgraduate Engineering and Science with over 200 teachers. This

university has a reputation for having a very good relationship between students and teachers.

RUET has continued to expand with the construction of new academic buildings, auditorium

complex, halls of residence, etc.

RUET is located on the north side of Rajshahi-Natore-Dhaka road at Kazla, 5 kilometers eastof Rajshahi city, on 152 acres (0.62 km2) of land. Known as green campus with a large

variety of trees, the campus is laid out with a picturesque landscape by the side of famous

Padma River and Rajshahi University.

The campus presents a spectacular harmony of architecture and natural beauty. The campus

area has been divided into function zones: residence for students, residential zones of faculty

and other supporting staff, academic zone for academic buildings and

laboratories/workshops, and cultural-cum-social and recreation zones for students. A bank

branch, post office, modern cafeteria, auditorium and medical center are on the campus. In

RUET there is a very big play ground and a central common room with a gymnasium for the

students. A secondary school and colleges are located in RUET to teach the children ofuniversity employees.

Rajshahi University of Engineering & Technology (RUET) was founded in 1964 as a faculty

of engineering under the University of Rajshahi providing four-year Bachelor degrees in

Civil, Electrical and Electronic and Mechanical Engineering. However, the institution could

not achieve its goal because of the complicated management system: The administration was

controlled by the Ministry of Education; academic curriculum by the University of Rajshahi;

and the infrastructural development and maintenance by the Public Works Department. To

circumvent these problems, several committees and commissions were formed since 1973.

On the recommendation of these committees/commissions and having considered the

practical aspects, autonomy was given to the four engineering colleges to make them centersof excellence of technology. A 15-member high-powered committee was formed, headed by

Professor Dr. Wahid Uddin Ahmed, the then vice chancellor of BUET.

The consistent effort of this committee ultimately led to the establishment of four engineering

colleges to Bangladesh Institute of Technology (BIT) in July 1986. But due to limited

autonomy and some constitutional inadequacies of the BIT ordinance, the expected progress

of the institutions could not be achieved. This ultimately necessitates re-framing the institutes

as full-fledged universities. Due to the development of Engineering Education it was the

appropriate steps to convert the four BITs to engineering and technological universities. The

parliament passed the university bill and that ultimately paved the way to commence the
http://en.wikipedia.org/wiki/Bangladeshhttp://en.wikipedia.org/wiki/Sciencehttp://en.wikipedia.org/wiki/Sciencehttp://en.wikipedia.org/wiki/Bangladesh


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activities of university from September 1, 2002. The name of the BIT became RajshahiUniversity of Engineering & Technology (RUET).

RUET is shown to be 316th (in Engineering & Technology sector) at "The World Top

University Ranking" searched in QS World Rankings 2011/12. However, It keeps 3rd Place

in Bangladesh IT sector while BUET is 271th, CUET 300th and KUET is 373th position(http://www.topuniversities.com/).

3.1.1 Student Health Service in RUET

An on-campus medical center provides primary and basic health care facilities to the students

free of charges. Two full-time MBBS doctors and other staffs provide these facilities. For

specialized consultation on complicated cases, the center refers the patients to specialist

consultants. There are a number of beds thatsnot designed with considering anthropometricdata of RUET students which is necessary for RUET students.

3.2 Questionnaires

The questionnaires we have prepared is shown below:

Date:

Name: Age:

Gender: Male Female Occupation:

1. Did each problem occur in your? Have you experienced any recurring symptoms such aspain, aching, numbness or any other symptom when you treat a patient?

Did each problem occur? Did this occur in the part of your body?

1. Neck Yes No Left Right Middle

2. Shoulder? Yes No Left Right Middle

3. Elbow? Yes No Left RightMiddle

4. Hand/wrist? Yes No Left Right Middle

5. Back? Yes No Left Right Middle

6. Hip? Yes No Left Right Middle

7. Knee? Yes No Left RightMiddle

8. Ankle? Yes No Left RightMiddle

2. Do you feel any problem for the height of the bad?

Yes

No; Height is ok.

If yes, then more height less height
http://www.topuniversities.com/http://www.topuniversities.com/


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3. Do you feel any problem for the length of the bed?

Yes No

If yes, then shorter length larger length

4. Do you feel any problem for the wide of the bed?

Yes No

If yes, then shorter wide longer wide

5. Do you feel any problem for stand height?

Yes No

If yes; then stand height is more stand height is less than standard.

6. Have you satisfied by using this bed?

Very satisfied somewhat satisfied Not too satisfied Not at all satisfied

7. In hospital what kinds of facility do you want from the hospital bed?

Ans.

8. For the following problems what factors of bed/anthropometry is responsible? Rank it like1,2,3,4.

Factors

Problems

Bedlength/Stature

Bed wide/Elbowspan

Bedheight/Popliteal

height

Bed standheight/Vertical

grip reach

1.Back pain

2. Fatigue

3. Bloodcirculation

problem

4. Comfort

5. Sleep


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3.3 Data collection

Collected data from doctors and patients

Factors

Problems

Bed length/

Stature

Bed width/

Elbow span

Bed height/

PoliticalHeight

Bed Stand

Height/Verticalgrip reach

Total

Back pain 58 23 0 0 81

Fatigue 37 21 51 11 120

Blood circulation

problem

32 29 43 21 125

Comfort 61 55 45 36 197

Sleep 59 48 2 7 116

Total 247 176 141 75 639


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Chapter 4

Result Analysis & Discussion

4.1 Result obtained by using Independent Test

1. H0= Problems are not related to anthropometric factors

2. H1= Problems are related to anthropometric factors

3. Level of significance,= 0.05, 0.014. Degree of freedom,= 125. 2actual= 144.154

6. 20.05, 12 = 21.026 > 2

actual

7. 20.01, 12 = 26.217 > 2actual

8. Decision: H0is rejected.

That means, problems are related to anthropometric factors.

4.2 Result obtained by using Analytic Hierarchy Process (AHP)

Table 4.1: Analytic Hierarchy Process (AHP)

Anthropometric

parameter

Attributes & their Weights Composite

weightRank

Backpain(0.468)

Fatigue(0.330)

Bloodcirculation

problem

(0.106)

Sleep(0.096)

Vertical grip reach

(Bed stand height)

0.110 0.096 0.200 0.070 0.172 3

Elbow span (Bed

width)

0.190 0.096 0.062 0.050 0.132 4

Popliteal Height (Bed

Height )

0.190 0.250 0.062 0.210 0.198 2

Stature (Bed length) 0.510 0.560 0.670 0.660 0.557 1

1. Result shows that for back pain, fatigue, blood circulation problem and sleep of patient bed

length is most responsible which is related to anthropometric factor stature.

2. After that, bed width is responsible which is related to anthropometric factor elbow span.

3. Then, bed height is responsible which is related to anthropometric factor popliteal height.

4. At last, Bed stand height is responsible which is related to anthropometric factor Verticalgrip reach.


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4.3 Result obtained by using Regression Analysis

Table 4.2: Mean and Standard deviation of anthropometric data

Stature (cm) Elbow span(cm) Popliteal height

(cm)

Vertical grip

reach(cm)

Mean 167.3141 88.33078 43.74369 201.8814

Standarddeviation

10.6542 3.8495 1.6215 14.2085

Table 4.3: Summary of the correlation analysis while taking independent variable x = stature

Dependent variables (Y) Prediction equation

Elbow span Y=0.850467x-52.4467

Popliteal height Y= 33.39599+0.05979x

Vertical grip reach Y=157.94156+0.2476x

From these equations if anyone give his stature height he will have proper dimension of

hospital bed.


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Chapter 5

Calculations

5.1 Independent Test:

Table 5.1: Collected data from doctors and patients

Factors

Problems

Bed length/

Stature

Bed width/

Elbow span

Bed height/

Political

Height

Bed Stand

Height/Vertical

grip reach

Total

Back pain 58 23 0 0 81

Fatigue 37 21 51 11 120

Blood circulation

problem

32 29 43 21 125

Comfort 61 55 45 36 197

Sleep 59 48 2 7 116Total 247 176 141 75 639

Let,

L= Bed length

W= Bed width

H= Bed height

Sh= Bed Stand Height

P= Back pain

F= Fatigue

B= Blood circulation problem

C= Comfort

S= Sleep

By using the marginal frequencies, we can list the following probability estimates:

P(L)= 247/639= 0.387

P(W)= 176/639= 0.275

P(H)= 141/639= 0.221

P(Sh)= 75/639= 0.117

P(P)= 81/639= 0.127

P(F)= 120/639= 0.188

P(B)= 125/639= 0.195


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P(C)= 197/639= 0.308

P(S)= 116/639= 0.182

Now, if H0 is true, that is problems are independent of anthropometric factors, we should

have,

P(LP) = P(L)P(P) = 0.3870.127 = 0.049P(LF) = P(L)P(F) = 0.073P(LB) = P(L)P(B) = 0.075P(LC) = P(L)P(C) = 0.119P(LS) = P(L)P(S) = 0.070P(W

P) = P(W)

P(P) = 0.035

P(WF) = P(W)P(F) = 0.052P(WB) = P(W)P(B) = 0.053P(WC) = P(W)P(C) = 0.085P(WS) = P(W)P(S) = 0.050P(HP) = P(H)P(P) = 0.028P(HF) = P(H)P(F) = 0.042P(HB) = P(H)P(B) = 0.043P(HC) = P(H)P(C) = 0.068P(HS) = P(H)P(S) = 0.040P(ShP) = P(Sh)P(P) = 0.015P(ShF) = P(Sh)P(F) = 0.022P(ShB) = P(Sh)P(B) = 0.023P(ShC) = P(Sh)P(C) = 0.036P(ShS) = P(Sh)P(S) = 0.021The expected frequencies are obtained by multiplying each cell probability by the totalnumber of observations. When Ho is true, the general rule for obtaining the expected

frequency of any cell is given by the following formula:

Expected frequency = (column total) (row total)/ (grand total)Thus, the expected numbers of frequency of bed length (L) that are not related to back pain

(P) are:


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() ()

The expected frequency for each cell is recorded in parentheses beside the actual observed

value in the following table:

Table 5.2: Expected and observed value

Factors

Problems

Bed length/

Stature

Bed width/

Elbow span

Bed height/

Political

Height

Bed Stand

Height/Vertical

grip reach

Total

Back pain 58(31.310) 23(22.310) 0(17.873) 0(9.507) 81

Fatigue 37(46.385) 21(33.051) 51(26.478) 11(14.085) 120

Blood circulation

problem

32(48.318) 29(34.429) 43(27.582) 21(14.671) 125

Comfort 61(76.148) 55(54.260) 45(43.469) 36(23.122) 197

Sleep 59(44.838) 48(31.950) 2(25.596) 7(13.615) 116Total 247 176 141 75 639

Degree of freedom,= (row1)(column1)= (5-1)(4-1)= 43= 12

Know,

2actual= (oi-ei)2

/ei

ei = expected frequency

oi= observed frequency

2actual=22.75+0.021+17.873+9.507+1.899+3.253+22.710+0.675+5.511+0.856+8.618+2.730+3.013+

0.010+0.054+7.173+4.473+8.062+21.752+3.214

2actual= 144.154Solution:

1. H0= Problems are not related to anthropometric factors

2. H1= Problems are related to anthropometric factors

3. Level of significance= 0.05, 0.014. Degree of freedom,= 125.

2

actual= 144.154


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6. 20.05, 12 = 21.026 > 2

actual

7. 20.01, 12 = 26.217 > 2

actual

8. Decision: H0is rejected.

That means, problems are related to anthropometric factors.

5.2 Study of approach under analytic hierarchy process

Table 5.3:Level of preference weight

Level of preference

weights

Definition Explanation

1 Equally Preferred Two activities contribute equally to the objective

3 Moderately Experience and judgment slightly favor one

activity over another

5 Strong

importance

Experience and judgment strongly or essentially

favor one activity over another

7 Noticeable

dominance

An activity is strongly favored over another and

its dominance demonstrated in practice

9 Extreme

importance

The evidence favoring one activity over another

is of the highest degree possible of affirmation

2,4,6,8 Intermediate

values

Used to represent compromise between the

preferences listed above

Reciprocals Reciprocals for inverse comparison

Figure 5.1: Analytic hierarchy process

Goal

Back pain

(C1)

Fatigue (C2) Blood

circulationproblem (C3)

Sleep (C4)

Stature (bed

length)

Elbow span

(bed wide)

Popliteal height

Bed hei ht

Vertical height

Bed stand


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Table 5.4: Evaluation at level 1

Attribute C1 C2 C3 C4 Geometric

mean

Normalized

weight

C1 1 2 5 3 2.34 0.468

C2 1 5 3 1.65 0.330

C3 1/5 1/5 1 2 0.53 0.106

C4 1/3 1/3 1 0.48 0.096

Total 2.03 3.53 11.5 9 5

Geometric mean for back pain, (1*2*5*3) ^ (1/4) =2.34

max = (Normalized weight of each row*sum of respective column)=0.468*2.03+0.33*3.53+0.106*11.5+0.096*9=4.197

Consistency Index (C.I) = (max-n)/ (n-1) = 0.0659 for n=4; R.I= 0.89Consistency Ratio (C.R) = C.I/R.I = 0.0659/0.89=0.074= 7.41 %< 10%, so acceptable.

Table 5.5: Average Random Index (RI) based on matrix size (adapted by Saaty)

N 1 2 3 4 5 6 7 8 9 10

RCI 0 0 0.52 0.89 1.11 1.25 1.35 1.40 1.45 1.49

Table 5.6: Evaluation for attribute for back pain

Parameter Stature

(bed

length)

Elbow

Height

Popliteal

height

Vertical

grip reach

Geometric

mean

Normalized

weight

Vertical

grip reach

1 1/2 1/2 1/4 0.5 0.11

Elbow

height

2 1 1 1/3 0.9 0.19

Poplitealheight

2 1 1 1/3 0.9 0.19

Stature

(Bed

length)

4 3 3 1 2.45 0.51

Total 9 5.5 5.5 1.91 4.75

Geometric mean for vertical grip reaches (Stand height) = (1*1/2*1/2*1/4) ^ (1/4) =.50

For Elbow Height = 0.90For Popliteal height = 0.90


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Similarly calculation for Stature (Bed length)

Eigenvector,max = (Normalized weight of each row* sum of respective column)

= (9*0.110+5.5*0.190+5.50*0.190+0.510*0.191)

= 4.0541

From Table 2 Random index for (n=4) = 0.89, Consistency Index CI= (maxn)/ (n1) =0.018

Consistency ratio CR=CI/RI=0.018/0.89=2.27%


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Table 5.8: Evaluation for attribute for blood circulation problem

Parameter Stature

(bed

length)

Elbow

Height

Popliteal

height

Vertical

grip reach

Geometric

mean

Normalized

weight

Verticalgrip reach

1 4 4 1/5 1.34 0.20

Elbow

height

1/4 1 1 1/9 0.41 0.062

Popliteal

height

1/4 1 1 1/9 0.41 0.062

Stature

(bed

length)

5 9 9 1 4.49 0.67

Total 6.5 15 15 1.42 6.65

Geometric mean for vertical grip reach (Stand height), (1*4*4*1/5) ^ (1/4) =1.34

Eigenvector max = (Normalized weight of each row*sum of respective column)=0.2*6.5+0.062*15+0.062*15+0.67*1.42=4.11

Consistency Index (C.I) = (max-n)/(n-1) = 0.0367 For n=4; R.I= 0.89.Consistency Ratio(C.R) = C.I/R.I = 0.0367/0.89=0.0412=4.12 %< 10%, so acceptable.

Table 5.9: Evaluation for attribute for sleep

Parameter Stature

(bed

length)

Elbow

Height

Popliteal

height

Vertical

grip reach

Geometric

mean

Normalized

weight

Vertical

grip reach

1 2 1/5 1/8 0.47 0.07

Elbow

height

1/2 1 1/4 1/9 0.34 0.05

Popliteal

height

5 4 1 1/5 1.41 0.21

Stature

(bed

length)

8 9 5 1 4.35 0.66

Total 14.5 16 6.45 1.44 6.57

Geometric mean for Vertical grip reach (Stand height) = (1*2*1/5*1/8) ^ (1/4)

=0.47

Eigenvector max = (Normalized weight of each row*sum of respective column)= (0.07*14.5+0.05*16+0.21*6.45+0.66*1.44)

=4.12

Consistency Index (CI) = (max-n)/(n-1) = 0.04 For n=4; R.I= 0.89Consistency Ratio (C.R) = C.I/R.I = 0.04/0.89=0.045=4.5 %< 10%, so acceptable


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Table 5.10: AHP for final evaluation

Anthropometric

parameter

Attributes & their Weights Composite

weight

Rank

Back

pain(0.468)

Fatigue

(0.330)

Blood

circulationproblem

(0.106)

Sleep

(0.096)

Vertical

grip

reach

(stand height)

0.110 0.096 0.200 0.070 0.172 3

Elbow span (Bed

width)

0.190 0.096 0.062 0.050 0.132 4

Popliteal Height (Bed

Height )

0.190 0.250 0.062 0.210 0.198 2

Stature (Bed length) 0.510 0.560 0.670 0.660 0.557 1

Sample calculation:

Composite weight for Vertical grip reach (Stand height)

=0.468*0.110+0.096*0.330+.2*0.106+0.070*0.096=0.172

Composite weight for Elbow span (Bed width)=0.468*0.190+0.096*0.330+0.062*0.106+0.050*0.096=0.132

Composite weight for Popliteal height (Bed height)

=.468*0.190+0.250*0.330+0.062*0.106+0.096*0.210=0.198

Composite weight for Stature (Bed

length)=0.4680*.510+0.560*0.330+0.670*0.106+0.660*0.096=0.557

5.3 One sided confidence bonds:

If is the mean of a random sample of size n from a population with variance 2, the one-sided

100(1-) % for is given by:

Upper one-sided bond: (+ z)/Lower one-sided bond: (- z)/5.4 Regression Analysis:

Mean, = Variance =

i-)2

/n

Standard deviation, =Variance


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A reasonable form of a relationship between the response Y and the regressor x is the linear

relationship

Y= a+bx

Where,

x= Independent variable or regressor

Y= Dependent variable or responses

a= Intercept

b= Slope

b=

i-

) (yi-

)/

i-

)

2

a= ( i-b i )/n = -bDue to patient safety for bed length, wide and height we have considered One sided

confidence bonds.

5.4.1 x = Stature and Y= Elbow span

= 0.05Here, = (+ z)/= 167.3141+ (1.64510.6542)/= 177.4630= (+ z)/= 88.33078+ (1.6453.8495)/= 98.4797

b= i-) (yi-)/ i-)2 = 11870.7/13957.86 = 0.0850467a= -b= 98.4797-0.850467177.4630 = -52.4467Y= a+bx

Y= 0.850467x52.4467This is the required equation shows relationship between strature and elbow span.

5.4.2. x = Stature and Y= Popliteal height

= 0.05= (+ z)/= 167.3141+ (1.64510.6542)/= 177.4630= (+ z)/= 43.74369(-1.6451.6215)/= 44.0065

b= i-) (yi-)/ i-)2= 834.6079/13957.86 = 0.05979a=

-b

= 44.0065-0.05979

177.4630 = 33.39599

Y= a+bx


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Y= 33.39599 + 0.05979 xThis is the required equation shows relationship between strature and popliteal height.

5.4.3 x = Stature and Y= Vertical grip reach (standing)

= (+ z)/= 167.3141+ (1.64510.6542)/= 177.4630y = = 201.8814

b= i-) (yi-)/ i-)2= 3455.973/13957.86 = 0.2476a= -b= 201.88140.2476177.4630 = 157.94156Y= a+bx

Y= 157.94156 + 0.2476 xThis is the required equation shows relationship between strature and vertical grip reach.


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Chapter 6

Recommendations and Future Work

Patient safety is a global issue that affects at all level of development. The design of hospital

bed should not be dependent on the esthetic views consideration but also should be dependenton the different dimensions of users body structure and postures. So the size and dimensionsof hospital bed will be different for people live in different region as human body dimension

varies with region to region. The integrated applications of esthetic view and anthropometricdata are critical factors for industrial designers in order to develop a satisfying product. More

anthropometric data will increase the accuracy of the model. In our case study we have only

used anthropometric data of 103 person and all are male. In future more anthropometric data

of both male and female will be helpful for the design of hospital bed. Also, there are various

types of hospital bed that should be design considering ergonomics and anthropometric data

of Bangladeshi people.Not only hospital bed, any furniture and work place should be

designed with considering ergonomics in order to increase productivity and human

satisfaction.


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Chapter 7

Conclusion

Every patient deserves a safe and comfortable sleeping and bed environment. Hospital bed

needed to design in such a way that both the patient and health care workers feel comfort,safe and convenience. Ergonomics or human factors are very important for the design ofhospital bed and other furniture. Our case study shows the relationship of hospital bed with

patient various problems like back pain, blood circulation problem, fatigue, sleep and comfortand what factors are responsible at most. This study gives a better solution for Bangladeshi

people to design hospital bed according to anthropometric data of this regional people. This

will increase patient safety and comfort for Bangladeshi people.


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Chapter 8

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Appendix

Anthropometric data

SL.No Name Stature(cm)

Elbow span(cm)

PoplitedHeight (cm)

VerticalGrip reach

(cm)

01 Md.Arif Uddin 170.18 89.00 41.40 202.30

02 Papon kumar paul 167.64 84.30 41.90 195.50

03 Faisal Rashed 167.64 93.00 43.00 207.60

04 Md.AR Rafiul Faisal 165.10 85.60 40.30 194.50

05 Md.Asaduzzaman 165.00 84.80 40.30 191.90

06 Md.Shahadat Hossain 165.10 85.00 43.30 197.10

07 Salim Mollah 170.18 87.80 45.30 203.10

08 Md.Shohel rana 170.18 91.10 41.50 207.10

09 Md.Idris Ali 167.64 82.50 41.80 202.0010 Rifat alam munna 162.56 81.10 43.50 190.50

11 Md.Ariful Islam 171.00 92.90 44.40 205.40

12 Muradul Islam 167.70 91.40 42.80 200.80

13 Debashahi kumar roy 163.83 86.90 41.20 196.70

14 Md.Ahahsan Habib 165.00 81.00 44.60 195.50

15 Md.Sojauddla 174.90 84.40 44.80 209.20

16 Md.Imran Hossain 171.90 89.50 43.60 209.30

17 Ali Ahsan Bappy 179.50 93.30 44.00 206.50

18 Ahasanul Haque Tarif 177.50 87.80 44.50 206.50

19 Shahed Mahuud 177.60 89.00 43.40 214.90

20 Md.Nashir Uddin 165.10 86.80 44.40 198.70

21 Md.Mostafizur 173.00 93.60 45.50 212.70

22 Md.Nazmul Hasan 160.00 85.80 41.70 196.50

23 Md.Rakibul Hasan 171.00 92.50 42.80 213.20

24 Md.Habibbur Rahman 170.18 85.50 44.90 209.20

25 Md.Abulmunger 170.20 90.30 43.80 202.20

26 Md.Abu Raihan 177.80 91.70 47.60 215.40

27 Khandaker Marsus 163.83 87.40 45.00 204.10

28 Md.Ershed Ali 171.45 92.20 45.00 208.20

29 Md.Mahedi Hasan 165.10 90.20 44.70 200.10

30 Md.Asaduzzaman 149.00 78.40 40.80 178.4031 Md.Hafiz Farukh 180.34 99.30 46.00 207.30

32 Iraj Ahmed 167.64 98.00 42.80 201.00

33 Md.Azizur Rahman 167.20 93.30 44.70 200.70

34 Md.Shahdat 162.56 87.00 41.00 195.00

35 Md.Sohel rana 162.56 91.40 41.90 202.20

36 Md.Hasan Sheikh 156.50 84.40 41.30 187.30

37 Md.Mahafujul Alam 168.90 88.40 44.30 203.20

38 Bipul kumar 172.20 94.80 46.00 201.70

39 Md.Asadul Haque 173.50 90.50 43.60 221.00

40 Md.Imam Hossain 161.30 85.60 44.90 198.2041 Md.Mamun Hossain 165.10 86.10 43.20 200.40


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SL.No Name Stature

(cm)

Elbow span

(cm)

Poplited

Height (cm)

Vertical

Grip reach

(cm)

42 Md.Abul Kalam Azad 178.00 96.10 44.20 206.9043 Md.Sultan Mahmd 161.00 86.00 42.00 194.40

44 Utpal Goswami 166.60 87.40 43.60 197.80

45 Nd.Enamul haque 161.90 91.60 43.80 198.00

46 Mahbibur Rahman 167.00 92.80 45.10 203.40

47 Masum saha badhon 168.00 90.00 44.70 205.20

48 Nasmus Sakib Khan 164.00 90.60 43.10 202.20

49 Tariful Islam 164.20 85.80 40.40 195.90

50 Md.Ali hasan 170.00 87.70 45.10 210.10

51 Ehsanul Haque 165.60 89.40 43.30 201.30

52 S.M.Nakib Hasan 163.50 86.10 41.80 196.50

53 Robiul Hasan 166.80 87.30 43.80 201.60

54 Md.Mahfuzul shekh 171.70 92.00 46.30 211.10

55 Md.Mesuk Ahmed 166.20 87.40 44.10 201.60

56 Md.Manik Hossain 161.60 84.02 44.70 191.80

57 S.M.Showyull Islam 172.30 88.80 44.80 209.80

58 Md.Monjur Bllahi 169.80 83.20 42.80 202.60

59 Md.Shafiqul Bari 164.50 84.10 43.30 200.70

60 Md.Sohel rana 175.60 92.10 45.90 213.70

61 Golam Mawla Newton 167.60 85.20 43.40 198.80

62 Md.Nurul Islam 157.20 83.80 41.10 191.20

63 Md.Akteruzzaman 177.70 96.30 45.70 218.8064 Md.Habibbur Rahman 168.80 84.50 44.50 190.00

65 Mobarak Hossain 170.20 91.00 45.40 207.60

66 Md.Rohidul Islam 167.10 90.40 43.10 202.40

67 Jafor Iqbal 157.70 86.60 43.30 198.90

68 Suaibur Rahman 179.00 95.00 47.00 219.20

69 Md.Al-Amin 159.20 87.20 42.10 190.20

70 Mamun Hossain Khan 169.20 87.50 42.50 202.40

71 Shaha Alam 163.40 86.20 43.20 194.88

72 Md.Muzahidul islam 161.20 89.40 44.60 198.50

73 Romanul-Ferdosh 163.80 85.40 44.70 201.2074 Shakawall Hossain 159.50 86.20 42.90 192.80

75 Md .Aminul Islam 159.30 87.20 42.20 195.60

76 Kumaresh biswas 161.40 92.50 42.60 195.10

77 Md.Feroz Ali 166.40 91.60 47.50 208.70

78 Md.Zillur Rahman 172.40 91.60 45.70 207.60

79 Shajedul Islam 169.80 93.70 44.10 204.70

80 Ripon Kumer saha 165.20 86.10 43.60 200.80

81 Dipu Bishwas 162.80 88.30 42.80 195.70

82 Tanvir Ahmed 166.40 87.90 43.00 203.50


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SL.No Name Stature(cm)

Elbow span(cm)

PoplitedHeight (cm)

Vertical Gripreach(cm)

83 Alinur rahman 164.30 88.80 45.40 200.80

84 Md.Fariduddin 157.90 83.80 42.40 190.20

85 Md.Feroz Ahmed 176.30 86.80 46.30 202.2086 Kamrulzzaman 172.60 87.10 46.70 207.30

87 Ali haider 169.80 87.40 43.00 200.50

88 Md .Liton ali 156.90 80.40 42.30 190.20

89 Md.Tariqul Islam 169.00 90.20 43.90 208.80

90 Aminul Islam 171.70 94.10 45.70 210.10

91 Md.Robiul Islam 164.40 86.70 43.60 204.10

92 Md.Rasal 171.20 83.80 45.00 204.90

93 Karim Ahmed 166.20 87.30 45.00 201.50

94 Salim Reza 173.30 93.40 44.20 201.20

95 Faruk Hossain 162.50 85.60 42.80 198.80

96 Abu Taher 162.20 83.90 41.80 199.2097 Atiar Rahman 167.00 89.20 42.70 200.00

98 Shahin Alam 176.80 91.00 45.20 213.10

99 Nazmul Islam Nahid 169.80 86.10 45.80 204.20

100 H.M.Kamal 170.00 83.80 45.60 203.10

101 Ram Prosad Halder 165.60 86.30 45.10 196.20

102 Md. Nuruzzaman 165.00 92.10 45.10 205.50

103 Md. Asadujjaman 162.60 84.30 42.00 202.20

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