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## Facility Layout 2

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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.