3. 1. Algorithmic Approaches
1. Closeness ratings or material flow intensities can be
reduced to an algorithmic process.
2. Generating and numerically evaluating a large
number of layout alternatives in a very short time.
3. Performing “what if” analysis based on varying the
input data or the layout itself.
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4. 2. Algorithm Classification
1) Based on Relationship Chart or Flow Chart
2) Based on Distance- based objective and Adjacency-
based objective
3) Discrete and Continuous layout Representation
4) Primary function- layout improvement or layout
construction
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7. 1) Distance based objective-
Minimize the sum of flows time distances
Flow from Deptt. i to j Cost of moving unit load
Distance
between
Deptt. i and j
2) Adjacency based objective-
Maximize the adjacency score
Adjacency Score (0 or 1)
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16. Procedure-
Step 1-
From the relationship chart, select the department
pair with the largest weight. Ties, if any are broken
arbitrarily. Thus Department 3 and 4 are selected
to enter in the graph.
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19. 5. CRAFT
1. It stands for Computerized Relative Allocation of
Facilities Technique.
2. It uses from- to chart as input data.
3. CRAFT begins by determining the centroid of the
departments in the initial layout.
4. CRAFT next considers all- possible two-way(pair
wise) or three way exchanges and identifies the
best exchange.
5. The final layout obtained in such a manner is also
known as a two- opt(three- opt) layout.
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20. 20
6. Since CRAFT is not capable of automatically shifting
departments in such a manner, it considers exchanging
only those that are adjacent or equal in area.
7. A computerized layout algorithm narrows down the
solution space.
21. 6. MCRAFT
1. A personal computer implementation of CRAFT.
2. MCRAFT can exchange any two department
whether they are adjacent or not.
3. MCRAFT is generally not as effective as CRAFT in
treating obstacle and fixed department.
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24. 24
4 Iterations-
1) Department C and E (59611.11 units)
2) Department C and H (58083.34 units)
3) Department C and D (57483.34 units)
4) Department B and C (57333.34 units)
26. 7. BLOCPLAN
1. BLOCPLAN uses a relationship chart as well as from-
to chart as input data for the flow.
2. Layout cost can be measured by the distance based
objective or adjacency based objectives.
3. BLOCPLAN may be used as a construction algorithm
and an improvement algorithm.
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29. 29
The maximum flow between value = 90 units
Dividing the above maximum by 5, and then taking intervals accordingly
73 to 90 units (A) 55 to 72 units (E) 37 to 54 units (I)
19 to 36 units (O) 0 to 18 units (U)
30. 8. MIP
1. Facility layout problem is formulated as a Mixed
Integer Programming (MIP) problem.
2. Model based on mathematical programming are
regarded as construction type layout models.
3. Problem parameters and Decision variables are
defined which leads to the mathematical model
consisting objective function and constraints.
4. Retaining flexibility in departmental area
requirements is necessary for effective use.
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31. 9. LOGIC
1. LOGIC (Layout Optimization with Guillotine Induced
Cuts) is based on dividing the building into smaller and
smaller portions by executing successive “guillotine”
cuts.
2. Layout cost is measured by the distance based objective
function.
3. MCRAFT, LOGIC can automatically shift other
department, but this may pose a problem if a fixed
department is shifted in the process.
4. Layout obtained by LOGIC are supersets of layouts
obtained by BLOCPLAN and similar algorithm that uses
“bands” for layout formation.
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34. 10. MULTIPLE
1. MULTIPLE stands for Multi- floor Plant Layout
Evaluation.
2. It uses a from- to chart as input data for the flow.
3. MULTIPLE is an improvement type layout algorithm.
4. MULTIPLE retains the flexibility of CRAFT while
relaxing CRAFT’s constraint imposed on department
exchanges.
5. MULTIPLE uses space- filling curves (SFCs)/ Hilbert
curve and grids allotted to department are sorted a
priori according to their sequence on the SFC.
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37. 37
Package Name of Vender
1. VisFactory (or e-Factory) Unigraphics Solutions Inc. (UGS)
2. LayOPT * Production Modeling Corporation, PMC
3. FactoryModeler * Systemes Escape Temps, Inc.
4. Nikan SET Technology Inc.
5. eM- Workplace Techomatrix Technologies Ltd.
6. PLANOPT Engineering Optimization Software
7. PLANET Engineering Optimization Software
38. References
1. James A. Tompkins, John A. White, Yavuz A.
Bozer, J.M.A. Tanchoco, Facility Planning, 3rd
ed., John Wiley and Sons, Inc.,2003
2. http://www.ignou4u.in/ignou-ms-5-study-
materialbooks/
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