FlowAnalysis-1

7/29/2019 FlowAnalysis-1

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Flow Analysis

Factors that Affect the Flow Pattern

Flow Analysis Information

Flow Patterns

a. Flow within Workstations b. Flow within Departments

c. Flow between Departments Flow Planning

Measuring Flow

Types of Layout

a. Fixed Location b. Product

c. Group Technology d. Processe. Hybrid

Flow Dominance Measure

Techniques for Machine Cell Formation

a. Row and Column Masking Algorithm

b. Single Linkage Clustering c. Average Linkage clustering


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Factors that Affect the Flow Pattern

Number of parts in each product

Number of operations on each part

Sequence of operations in each part

Number of subassemblies

Number of units to be produced

Product versus process type layout

Desired flexibility

Locations of service areas The building

. . . .


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Flow Analysis Information

Assembly Chart

Operations Process Chart

Flow Process Chart

Multi-Product Process Chart

Flow Diagram

From-To Chart


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Assembly Chart

It is an analog model of the assembly

process. Circles with a single link denote

basic components, circles with several

links denote assemblyoperations/subassemblies, and squares

represent inspection operations. The

easiest method to constructing an

assembly chart is to begin with the

original product and to trace the product

disassembly back to its basic components.


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Operations Process Chart

By superimposing the route sheets and

the assembly chart, a chart results that

gives an overview of the flow within

the facility. This chart is operations

process chart.


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Flow Process Chart

This chart uses circles for

operations, arrows for transports,squares for inspections, triangles

for storage, and the letter D for

delays. Vertical lines connect these

symbols in the sequence they are

performed.


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Multi-Product Process Chart

This chart is a flow process chart

containing several products.


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Flow Diagram

It depicts the probable

movement of materials in thefloor plant. The movement is

represented by a line in the plant

drawing.


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From-To Chart

This chart is a matrix that

contains numbers representing ameasure (units, unit loads, etc.)

of the material flow between

machines, departments,

buildings, etc.


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Flow Patterns: Flow within Workstations

Motion studies and ergonomics considerations are important in

establishing the flow within workstations. Flow within workstations

should be:

Simultaneous: coordinated use of hands, arms and feet.

Symmetrical: coordination of movements about the center of the

body.

Natural: movements are continuous, curved, and make use of

momentum.

Rhythmical and Habitual: flow allows a methodological and

automatic sequence of activities. It should reduce mental, eye and

muscle fatigue, and strain.


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Flow Patterns: Flow within Departments

The flow pattern within departments depends on the type of

department.

In a product and/or product family department, the flow follows the

product flow.1 machine/operator

1 machine/operator 2 machines/operator

1 machine/operator

More than 2

machines /operator


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Flow Pat.: Flow within Departments (cont.)

In a process department, little flow should occur between workstations

within departments. Flow occurs between workstations and isles.

Aisle

Aisle

Aisle

Aisle

Aisle

Dependent on interactions among workstations

available space

size of materials

Uncommon

One way

One way


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Flow Pat.: Flow between Departments

Flow between departments is a criterion often used to evaluate flow

within a facility.

Flow typically is a combination of the basic horizontal flow patterns

shown below. An important consideration in combining the flow

patterns is the location of the entrance (receiving department) and exit

(shipping department).

Straight

U flow

Serpentine

L flow

S flow

Circularflow

Simplest. Separate

receiving/shipping

crews

Very popular.

Combine receiving/shipping. Simple to

administer

When line is too long

Similar to straight.

It is not as long.

Terminate flow.Near point of origin


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Flow within a facility considering the

locations of entrance and exit

At the same location

On adjacent sides


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Flow within a facility considering the

locations of entrance and exit (cont.)

On the same side but

at opposite ends

On opposite sides


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Vertical Flow Pattern

Flow between buildings exists

and the connection between

buildings is elevated

Ground level ingress (entry)

and egress (exit) are required

Ground level ingress (entry)

and egress (exit) occur on the

same side of the building

Travel between floors occurs on

the same side of the building

Some bucket and belt

conveyors and escalators result

in inclined flow

Backtracking occurs due to the

return to the top floor


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Flow Planning

Planning effective flow involves combining the above patterns with adequate isles

to obtain progressive movements from origin to destination.

An effective flow can be achieved by maximizing directed flow paths, reducing

flow, and minimizing the costs of flow.

A directed flow path is an uninterrupted flow path progressing directly from

origin to destination: the Figure below illustrates the congestion and undesirableintersections that may occur when flow paths are interrupted.

Uninterrupted flow paths

Interrupted flow paths


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Flow Planning (cont.)

The reduction of flow can be achieved by work simplification including:

1. Eliminating flow by planning for the delivery of materials, information, or people

directly to the point of ultimate use and eliminate intermediate steps.

2. Minimizing multiple flows by planning for the flow between two consecutive points

of use to take place in as few movements as possible.

3. Combining flows and operations whenever possible by planning for the movement of

materials, information, or people to be combined with a processing step.

Minimizing the cost of flow can be achieved as follows:

1. Reduction of manual handling by minimizing walking, manual travel distances, and

motions.

2. Elimination of manual handling by mechanizing or automating flow.


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Measuring Flow

1. Flow among departments is one of the most important factors in the arrangement of departments

within a facility.

2. Flows may be specified in a quantitative manner or a qualitative manner. Quantitative measures

may include pieces per hour, moves per day, pounds per week. Qualitative measures may range

from an absolute necessity that two departments show be close to each other to a preference that

two departments not being close to each other.

3. In facilities having large volumes of materials, information, a number of people moving between

departments, a quantitative measure of flow will typically be the basis for the arrangement of

departments. On the contrary, in facilities having very little actual movement of materials,

information, and people flowing between departments, but having significant communication

and organizational interrelation, a qualitative measure of flow will typically serve as the basisfor the arrangement of departments.

4. Most often, a facility will have a need for both quantitative and qualitative measures of flow and

both measures should be used.

5. Quantitative flow measure: From-to Chart

Qualitative flow measure: Relationship (REL) Chart


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Quantitative Flow Measurement

A From-to Chart is constructed as follows:

1. List all departments down the row and across the column following the overall

flow pattern.

2. Establish a measure of flow for the facility that accurately indicates equivalent

flow volumes. If the items moved are equivalent with respect to ease of movement,

the number of trips may be recorded in the from-to chart. If the items moved vary

in size, weight, value, risk of damage, shape, and so on, then equivalent items may

be established so that the quantities recorded in the from-to chart represent theproper relationships among the volumes of movement.

3. Based on the flow paths for the items to be moved and the established measure of

flow, record the flow volumes in the from-to chart.


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Example 1

Stores

Turning

Milling

Press

Plate

Assembly

Warehouse

6 12 9 1 4

3 4

7 2

3 1 1

1 3 4 3

1 7

Stores

Turning

Milling

Press

Plate

Assembly

Warehouse

Stores

Milling

Turning

Press

Plate

Assembly

Warehouse

12 6 9 1 4

7 2

3 4

3 1 1

3 1 4 3

1 7

Stores

Milling

Turning

Press

Plate

Assembly

Warehouse

From-to Chart

Original Flow Pattern Revised Flow Pattern


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Flow Patterns

Store

Turning

Milling

Press

Plate

Assembly

Warehouse

Stores Turning Milling

Warehouse Assembly Plate

Press

Stores Press Plate Assembly

Turning Milling Warehouse

Stores Milling Warehouse

Turning Press Plate Assembly

Straight-line flow U-shaped flow

W-shaped flowS-shaped flow


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Flow Patterns (cont.)

Store

Turning

Milling

Press

Plate

Assembly

Warehouse

Stores Turning Milling

Warehouse Assembly Plate

Press

Stores Press Plate Assembly

Turning Milling Warehouse

Stores Milling Warehouse

Turning Press Plate Assembly

Straight-line flow U-shaped flow

W-shaped flowS-shaped flow


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Qualitative Flow Measurement

A Relationship (REL) Chart is constructed as follows:

1. List all departments on the relationship chart.

2. Conduct interviews of surveys with persons from each department listed on the

relationship chart and with the management responsible for all departments.

3. Define the criteria for assigning closeness relationships and itemize and record the

criteria as the reasons for relationship values on the relationship chart.

4. Establish the relationship value and the reason for the value for all pairs of

departments.

5. Allow everyone having input to the development of the relationship chart to have

an opportunity to evaluate and discuss changes in the chart.


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Relationship Chart

Code Reason

1 Frequency of use high

2 Frequency of use medium

3 Frequency of use low

4 Information flow high

5 Information flow medium

6 Information flow low

Rating Definition

A Absolutely Necessary

E Especially Important

I Important

O Ordinary Closeness OK

U Unimportant

X Undesirable

1. Directors conference room

2. President

3. Sales department

4. Personnel

5. Plant manager

6. Plant engineering office

7. Production supervisor

8. Controller office

9. Purchasing department

I

1

O

5

U

6

O

5

A

4

I

4

U

6

I

4

I

1

U

6

I

4

O

5

A

4

O

5

O

5

U

3

O

5

O

5

O

5

O

5

E

4

O

2

U

6

O

5

O

5

O

5

U

3

U

6

E

4

O

4

U

3

I

4

I

4

U

3

O

5

U

6


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Types of Layout

Volume

High

Medium

Low

Low Medium High Variety

Product

Planning

Department

Fixed MaterialsLocation

Planning

Department

ProcessPlanning

Department

Product

Family

Planning

Department

Product

Layout

Fixed Location

Layout

Group Technology

Layout

Process

Layout


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Fixed Product Layout

Lathe Press Grind

Weld AssemblyPaint

St

o

r

a

g

e

W

a

r

e

h

o

u

s

e


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Fixed Product Layout (cont.)

Advantages

1. Material movement is reduced.

2. Promotes job enlargement by allowing individuals or teams to perform the whole job.

3. Continuity of operations and responsibility results from team.

4. Highly flexible; can accommodate changes in product design, product mix, and product volume.

5. Independence of production centers allowing scheduling to achieve minimum total production

time.

Limitations

1. Increased movement of personnel and equipment.

2. Equipment duplication may occur.

3. Higher skill requirements for personnel.4. General supervision required.

5. Cumbersome and costly positioning of material and machinery.

6. Low equipment utilization.


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Product Layout

Drill Grind Drill

Lathe

Drill

Drill

St

o

r

a

g

e

W

a

r

e

h

o

u

s

e

As

s

e

m

b

l

y

Lathe

Bend

Lathe

Mill

Press

Drill


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Product Layout (cont.)

Advantages

1. Since the layout corresponds to the sequence of operations, smooth and logical flow lines result.

2. Since the work from one process is fed directly into the next, small in-process inventories result.

3. Total production time per unit is short.

4. Since the machines are located so as to minimize distances between consecutive operations, material

handling is reduced.

5. Little skill is usually required by operators at the production line; hence, training is simple, short,

and inexpensive.

6. Simple production planning control systems are possible.

7. Less space is occupied by work in transit and for temporary storage.

Limitations1. A breakdown of one machine may lead to a complete stoppage of the line that follows that machine.2. Since the layout is determined by the product, a change in product design may require major

alternations in the layout.

3. The pace of production is determined by the slowest machine.

4. Supervision is general, rather than specialized.

5. Comparatively high investment is required, as identical machines (a few not fully utilized) are

sometimes distributed along the line.


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Process Layout

Lathe Drill Weld

Mill

Drill

Grind

St

o

r

a

g

e

W

a

r

e

h

o

u

s

e

Lathe

Lathe

Mill

Mill

Lathe

Mill

Paint

Grind

Assembly

Assembly

Paint

Weld


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Process Layout (cont.)

Advantages

1. Better utilization of machines can result; consequently, fewer machines are required.

2. A high degree of flexibility exists relative to equipment or man power allocation for specific

tasks.

3. Comparatively low investment in machines is required.

4. The diversity of tasks offers a more interesting and satisfying occupation for the operator.

5. Specialized supervision is possible.

Limitations1. Since longer flow lines usually exist, material handling is more expensive.

2. Production planning and control systems are more involved.

3. Total production time is usually longer.4. Comparatively large amounts of in-process inventory result.

5. Space and capital are tied up by work in process.

6. Because of the diversity of the jobs in specialized departments, higher grades of skill are

required.


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Group Layout

Drill Grind Assembly

Drill

Weld

Assembly

St

o

r

a

g

e

W

a

r

e

h

o

u

s

e

Lathe

Assembly

Grind

Press

Mill

Lathe

Paint

Drill

Drill

Press

Grind

Assembly


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Group Layout (cont.)

Advantages

1. Increased machine utilization.

2. Team attitude and job enlargement tend to occur.

3. Compromise between product layout and process layout, with associated advantages.

4. Supports the use of general purpose equipment.5. Shorter travel distances and smoother flow lines than for process layout.

Limitations1. General supervision required.

2. Higher skill levels required of employees than for product layout.

3. Compromise between product layout and process layout, with associated limitations.

4. Depends on balanced material flow through the cell; otherwise, buffers and work-in-processstorage are required.

5. Lower machine utilization than for process layout.


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Hybrid Layout

Combination of the layouts discussed.

A sample hybrid layout that has characteristics of group, process and product

layout is shown in the following figure.

A combination of group layout in manufacturing cells, product layout in assembly

area, and process layout in the general machining and finishing section is used.

TM

TM TM

TM TMDM

BM


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Flow Dominance Measure

Notations:

M: number of activities.

Nij: number of different types of items moved between activities i and j.

fijk: flow volume between i and j for item k (in moves/time period).

hijk: equivalence factor for moving item k with respect to other items moved

between i and j (dimensionless).

wij: equivalent flow volume specified in from-to chart (in moves/time period),

w = f h .ij ijk ijk k

N ij

1


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Flow Dominance Measure (cont.)

Flow dominance measure = f =

where

f f

f f

U

'

U L

f

w M w

M 1

w, w =

w

M

f MM M 1

(M 1)(M 1), f M

1

(M 1)(M 1)

'

ij

2 2 2

j 1

M

i 1

M

2

1

2

ijj 1

M

i 1

M

2

U

2

2 L 2

1

2

1

2

fis the coefficient of variation. fL and fU are lower and upper bounds on f, respectively (fL f fU).

The upper bound fU is only guaranteed to work when each process plan includes all

activities. In this case, 0 f 1.


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Flow Dominance Measure (cont.)

Three cases :

1. f 0 a few dominant flows exist. product layout.

can use operations process chart as starting point for developing layout and

material handling system design. quantitative measures principal source of activity relationship.

2. f 1 many nearly equal flows exist.

any layout equally good with respect to flows .

qualitative measures principal source of activity relationship.

3. 0


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Example 2

Given three machines (activities) labeled 1, 2 & 3,

Product

A

B

C

Process Plan

1 - 2 - 3

2 - 1

3 - 1 - 2

Quantities/Shift

10

5

15

Assume Product B is twice as difficult to move as A or C hijB = 2 and hijA = hijC = 1

To

From

1

2

3

1

0

2 5

10

1 15

15

2

110

1 1525

0

0

3

0

1 10

10

0

Equivalent

Flow Volume

From-To Chart

w12 = 25,

w21 = 10, etc


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Example 2 (cont.)

M = 3 and

f3 1

6.67= .352

f 33 3 1

(3 1)(3 1)

= 1.984 and f 31

(3 1)(3 1)

f

'

2

U

2

2 L 2

( ) ( . )

.

. .

. ..

25 10 10 15 3 6 67

1

0 75

1984 1352

1984 0 7505122

2 2 2 2 2 212

1

2

1

2

w =(25 10 10 15)

36.672

no dominant flows exist

(likely, since 3 different process plans)


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Qualitative Measures

Closeness values (A, E, I, O, U, X) used to indicate physical proximity

requirements between activities.

Relationship Chart can only show symmetric relationships, as compared to

From-to Chart (wij wji possible).

Relationship Chart is starting point for developing layout when 0


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Conversion Method

To convert equivalent flow volumes to closeness values for the example

problem, use wij + wji to make them symmetric.

Conversion relations :

20 < wij + wji A w12 + w21 = 25 + 15 A

12 < wij + wji 20 E w13 + w31 = 0 + 15 E

5 < wij + wji 12 I w23 + w32 = 10 + 0 I

0 < wij + wji 5 O

wij + wji = 0 U

A

IE

Machine 1

Machine 2

Machine 3


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Group Technology

Group Technology (GT) is a management philosophy that attempts to group

products with similar design or manufacturing characteristics, or both.

Cellular Manufacturing (CM) is an application of GT that involves grouping

machines based on the parts manufactured by them.

The main objective of CM is to identify machine cells and part families

simultaneously, and to allocate part families to machine cells in a way that

minimizes the intercellular movement of parts.

Potential benefits of CM:

* Setup time reduction. * Improvement in quality.

* Work-in-process (WIP) reduction. * Improvement in material flow.* Material handling cost reduction. * Improvement in machine utilization.

* Direct/indirect labor cost reduction. * Improvement in space utilization.

* Improvement in employee moral.


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Group Technology (cont.)

A cellular manufacturing system (CMS) designer must consider a number of

constraints:

Available capacity of machines in each cell cannot be exceeded.

Safety and technological requirements pertaining to the location of equipment and

processes must be met. The size of a cell and the number of cells must not exceed a user-specified value.

Design analysis begins with a machine-part indicator matrix A = [aij] of size

mn, where m is the number of machines and n the number of parts.

Typically the matrix consists of 0 and 1 entries:

aij = 1 indicates that part j is processed by machine i.

aij = 0 indicates that part j is not processed by machine i.

Analysis attempt to rearrange the rows and columns of the matrix to get a

block diagonal form as shown in the following example.


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Example 3

Initial Machine Part

Processing Matrix

Rearranged Machine-Part

Processing Matrix

P1 P2 P3 P4P5 P6

M1

M2

M3

M4

M5

M6

M7

1

1 1 1

1 11

1 1

1

1

1 1

Part

Ma

chine

P1 P3 P2 P4P5 P6

M1

M4

M6

M2

M3

M5

M7

1

1 1

1 1

1 1 1

1 11

1

Part

Ma

chine


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Row and Column Masking (R&CM) Algorithm

1. Draw a horizontal line through the first row. Select any 1 entry in the matrix

through which there is only one line.

2. If the entry has a horizontal line, go to step 2a. If the entry has a vertical line,

go to step 2b.

2a. Draw a vertical line through the column in which this 1 entry appears. Go to

step 3.

2b. Draw a horizontal line through the row in which this 1 entry appears. Go to

step 3.

3. If there is any 1 entries with only one line through them, select any one and go

to step 2. Repeat until there are no such entries left. Identify the correspondingmachine cell and part family. Go to step 4.

4. Select any row through which there is no line. If there are no such rows, stop.

Otherwise, draw a horizontal line through this row, select any 1 entry in the

matrix through which there is only one line, and go to step 2.


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Example 3 Solution

Identification of the First Machine

Cell and Part Family

Identification of the Second Machine

Cell and Part Family

P1 P2 P3 P4P5 P6

M1

M2

M3

M4

M5

M6

M7

1

1 1 1

1 11

1 1

1 1

1 1

Part

Machine

2

3

4

1 5

P1 P2 P3 P4P5 P6

M1

M2

M3

M4

M5

M6

M7

1

1 1 1

1 11

1 1

1 1

1 1

Part

Machine

2

3

4

7

1 5 8

6


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Single Linkage (S-Link) Clustering Algorithm

S-Link is the simplest of all clustering algorithms based on the similarity

coefficient method.

The similarity coefficient between two machines is defined as the number of

parts visiting the two machines divided by the number of parts visiting either

of the two machines.

1. pairwise similarity coefficients between machines are calculated and stored in

the similarity matrix.

2. The two most similar machines join to form the first machine cell.

3. The threshold value (the similarity level at which two or more machine cellsjoin together) is lowered in predetermined steps and all machine/machine cells

with the similarity coefficient greater than the threshold value are grouped into

larger cells.

4. Step 3 is repeated until all machines are grouped into a single machine cell.


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Example 4: Initial Machine Part Matrix

P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 P13 P14 P15 P16 P17 P18 P19 P20 P21 P22

M1

M2

M3

M4

M5

M6

M7

M8

M9

M10

M11

1 1 1 1 1 1 1

1 1

1 1 1 1 1

1 1 1 1 1

1 1 1 1 1 1 1

1 1

1 1 1 1 1 1 1

1 1

1 1 1 1

1 1 1 1 1 1

Part

Machine


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Example 4: Initial Similarity Coefficient Matrix

M1 M2 M3 M4 M5 M6 M7M8 M9 M10 M11

M1

M2

M3

M4

M5

M6

M7

M8

M9

M10

M11

0.08

0.00 0.43

1.00 0.08 0.00

0.80 0.00 0.00 0.80

0.00 0.80 0.50 0.00 0.00

0.00 0.00 0.10 0.00 0.00 0.00

0.00 0.25 0.50 0.00 0.00 0.27

0.45

0.00 0.00 0.00 0.00 0.00 0.00

0.83 0.36

0.43 0.45 0.23 0.43 0.43 0.36

0.00 0.17 0.00

Machine

Machine


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Example 4: Dendrogram Based on S-Link

M1 M4 M5 M2 M6 M3 M8M10 M7 M9 M11

Machine

0.00

0.25

0.50

0.75

1.00

Similarity

Levels


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Example 4: Machine Part Groups using S-Link


M5

M1

M4

M10

M2

M6

M3

M8

M7

M9

M11

1 1 1 1 1 1 1 1 1

1 1 1 1 1 1 1 1 1

1 1 1 1 1 1 1 1 1

1 1 1 1 1 1 1 1 1 1 1

1 1 1 1 1

1 1 1 1

1 1 1 1 1

Part

Machine


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Average Linkage (A-Link) Clustering Algorithm

The similarity coefficient between two machine cells is defined as the average

of pairwise similarity coefficients between all members of the two cells.

1. Compute pairwise similarity coefficients between machines and construct the

similarity coefficient matrix.

2. Merge the two most similar machines into a single machine cell.

3. Compute the similarity coefficients between the newly formed machine cell

and the remaining cells. Revise the similarity coefficient matrix.

4. The threshold value (the similarity level at which two or more machine cells

join together) is lowered in predetermined steps and all machine/machine cellswith the similarity coefficient greater than the threshold value are grouped into

larger cells. Repeat steps 3 and 4 until all machines are grouped into a single

machine cell.


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Example 4: Revised Similarity Coefficient Matrix I

(M1,M4) (M2,M6) M3 M5 (M7,M9) M8 M10 M11

(M1,M4)

(M2,M6)

M3

M5

(M7,M9)

M8

M10

M11

0.04

0.00 0.47

0.80 0.00 0.00

0.00 0.00 0.05 0.00

0.00 0.26 0.50 0.00 0.41

0.43 0.41 0.23 0.43 0.00 0.17

0.00 0.00 0.00 0.00 0.62 0.36 0.00

Machine Cell

MachineCell


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Example 4: Revised Similarity Coefficient Matrix II

(M1,M4 ,M5) (M2,M6) M3 (M7,M9,M11) M8 M10

(M1,M4,M5)

(M2,M6)

M3

(M7,M9,M11)

M8

M10

0.02

0.00 0.47

0.00 0.00 0.03

0.00 0.26 0.50 0.39

0.43 0.41 0.23 0.00 0.17

Machine Cell

MachineCell


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Example 4: Revised Similarity Coefficient Matrices III & IV

(M1,M4 ,M5) (M2,M6) (M3,M8) (M7,M9,M11)M10

(M1,M4,M5)

(M2,M6)

(M3,M8)

(M7,M9,M11)

M10

0.02

0.00 0.37

0.00 0.00 0.21

0.43 0.41 0.20 0.00

Machine Cell

Machin

eCell

(M1,M4,M5,M10) (M2,M6, M3,M8) (M7,M9,M11)

(M1,M4,M5,M10)

(M2,M6, M3,M8)

(M7,M9,M11)

0.02

0.00 0.11

Machine Cell

MachineCell


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Example 4: Dendrogram Based on A-Link

M1 M4 M5 M10 M2 M6 M3M8 M7 M9 M11

Machine

0.00

0.25

0.50

0.75

1.00

Similarity

Levels


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Example 4: Machine Part Groups using A-Link


M5

M1

M4

M10

M2

M6

M3

M8

M7

M9

M11

1 1 1 1 1 1 1 1 1

1 1 1 1 1 1 1 1 1

1 1 1 1 1 1 1 1 1

1 1 1 1 1 1 1 1 1 1 1

1 1 1 1

1 1 1 1

1 1 1 1 1

Part

Machine


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Comparison

R&CM is the simplest clustering algorithm.

A major disadvantage of R&CM is that when the machine part matrix contains one or more

bottleneck machines (machines that belong to more than one cell) or exceptional parts (parts

that are processed in more than one cell), the algorithm may provide a solution with all

machines in a cell and all parts in a corresponding part family.

The major advantages of S-Link are its simplicity and minimal computational requirement.In S-Link, once pairwise similarity coefficients are computed and the similarity coefficient

matrix is constructed, the matrix can be used to develop the dendrogram which represents

the machine cells at different threshold values.

The major drawback of S-Link is the chaining problem. Due to the chaining problem, two

machine cells may join together just because two of their members are similar while the

remaining members may remain far apart in terms of similarity.

The chaining problem of S-Link can be overcome by using A-Link. Since in A-Link two

machine cells merge based on the overall similarity coefficient between all their members, it

is unlikely that two similar members in two cells cause the cells to merge while other

members are not similar enough. A-Link provides a more reliable solution to the machine

FlowAnalysis-1

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