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Facility Layout 2. Basic Data and Layout Evaluation. The objective is to design a block layout. 1. 2. 3. 4. 5. 4b. Show the general placement, dimensions and relative position of departments. Block Layout. Next, how do we evaluate the block layout. 2. 1. 3. 4.
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Facility Layout 2 Basic Data and Layout Evaluation
The objective is to design a block layout. 1 2 3 4 5 4b Show the general placement, dimensions and relative position of departments Block Layout
Next, how do we evaluate the block layout. 2 1 3 4 • Flow Patterns – qualitatively • Qualitatively generated reward matrix • REL chart • Maximize A-based measure • Quantitatively generated reward matrix • Flow x Distance x Cost • Minimize this D-based objective 100 200 100 100 100
An example ABC Widgets Inc. is trying to create a layout for a new facility. The lot of terrain available is a square, 300 ft. by 300 ft. The company is organized in four departments, with the following dimensions: Dept 1: 100’ x 300’ Dept 2: 100’ x 200’ Dept 3: 100’ x 200’ Dept 4: 100’ x 200’ First, try to build a couple of feasible layouts in the next page
Let’s play with layouts 300 x 300 300 x 300 300 x 300 2 4 1 1 4 2 3 3
It is absolutely necessary that depts. 1 and 2 are close, and it is especially important that 1 and 4 are close. It is also important that 3 and 4 are somehow close and it’s OK if departments 2 and 4 are close to each other. Other than that, all other relationships are unimportant. Now, let’s explore the relationships between the departments Rating Definition A Absolutely Necessary E Especially Important I Important O Ordinary Closeness OK U Unimportant X Undesirable
In this example, we will calculate an Adjacency Based and a Distance Based Score for two layouts 2 2 1 1 4 3 4 3 100 100 100 200 100 100 100 100 100 200 Layout 1 Layout 2
Step 1: Convert REL data to a Reward Matrix A = 8 E = 4 I = 2 O = 1 U = 0 (X = -8) Scores are usually powers of a base number fij
Step 2: Find the Adjacency-Based score xij = 1 if the departments are adjacent = 0 if the departments are not adjacent • Adjacency means that they share a border, not corners • Layouts with same adjacency score may have different travel distances
Here is the data we need 2 2 1 1 100 100 4 3 4 100 3 200 100 100 100 100 100 200 Layout 1 Layout 2 ABS1 = 11 fij ABS2 = 15
Step 3: Find the Relative Efficiency for both layouts ABS1 Rel. Efficiency1 = = 73% ABS2 Rel. Efficiency2 = = 100%
Back to the company Now we will obtain some data related to the production processes that take place on ABC Widgets fij Size of the unit load 50 1 200 units a day 200 25 1 2 4 100 3
Step 1: Find the flow data In this example, we will use the number of daily trips between departments fij f flow between dept i and j c cost of moving the load (independent of MHE) d distance from dept i to j (Centroid-to-Centroid and Rectilinear)
How do we calculate Rectilinear Distances? Rectilinear Distance means that we move horizontally and vertically, not diagonally Does this make sense? When or where? Rect. Dist. = dx + dy y2 dy dx Rect. Dist. = |x1-x2| + |y1-y2| y1 x1 x2
Step 2: Let’s find the the distances between departments Rectilinear Distances Centroids 2 1 100 3 4 200 100 100 100 2 1 100 4 100 3 100 100 200
Step 3: Find the Distance Based score DBS1 = 3400 fij DBS2 = 2900
Next few classes will we discuss FLP algorithms. 1 2 3 4 5 4b • Methods to generate layouts from scratch or just generating improvements to layouts. • Once we have a layout, we use our D-based and A-based measures to compare the layouts and select the best alternative.