Exam 23: Transportation Models

A firm has established a distribution network for the supply of a raw material critical to its manufacturing. Currently there are two origins for this raw material, which must be shipped to three manufacturing plants. The current network has the following characteristics: COSTS Plant 1 Plant 2 Plant 3 Supply Raw material source 1 \ 6 \ 8 \ 9 400 Raw material source 2 \ 4 \ 7 \ 3 600 Demand 500 500 500 1500\backslash1000 The firm has identified two potential sites for a third raw material source; these are identified as Candidate A and Candidate B. From A, the costs to ship would be $9 to Plant 1, $10 to Plant 2, and $12 to Plant 3. From B, these costs would be $11, $14, and $8. The new source, wherever it is located, will have a capacity of 500 units. Set up-but DO NOT SOLVE- this problem as though you were going to solve it with transportation problem software.

A transportation problem has 10 origins and 32 destinations. How many possible routes are there for this problem? How many routes will be used in the optimal solution?

The purpose of the transportation approach for location analysis is to minimize

A transportation problem requires exactly as many origins as destinations.

In a transportation minimization problem, the negative improvement index associated with a cell indicates that reallocating units to that cell would lower costs.

Which of the following combinations of sources and destinations would fill no more than 25% of cells with quantities to be shipped for the optimal solution?

What purpose does the northwest-corner rule serve?

The stepping-stone method frequently achieves an optimal solution as soon as it calculates an initial feasible solution.

Consider the transportation problem and its optimal solution in the tables below. The cell Source 3 - Destination 3 is currently empty. What would be the change in the objective function if the largest possible amount were shipped using that route, leaving all the supply and demand conditions unchanged? COSTS Dest. 1 Dest. 2 Dest. 3 Dest. 4 Supply Source 1 12 18 9 11 105 Source 2 19 7 30 15 145 Source 3 8 10 14 16 50 Demand 80 60 70 90 300/300 Shipments Dest. 1 Dest. 2 Dest. 3 Dest. 4 Row Total Source 1 30 0 70 5 105 Source 2 0 60 0 85 145 Source 3 50 0 0 0 50 Col. Total 80 60 70 90 300/300

What is transportation modeling?

A transportation model uses at least 10 sources and 100 destinations. If the ratio of sources to destinations remains constant, does the maximum % of cells used by the optimum solution remain constant? Why or why not?

Which of the following is not information needed for a transportation problem?

What is the difference between a feasible solution and an optimal solution?

An improvement index indicates