Page 175 - DCOM303_DMGT504_OPERATION_RESEARCH
P. 175

Operations Research




                    Notes          Travelling Salesman Problem: The problem in  combinatorial optimization in which, given a
                                   number of cities and the costs of travelling from one to the other, it is required to determine the
                                   cheapest route that visits each city once and then returns to the initial city.

                                   8.8 Review Questions

                                   1.  Discuss the variations in assignment problem.
                                   2.  Can there be multiple optimal solutions  to an  assignment problem? How would you
                                       identify the existence of multiple solutions if any?
                                   3.  How would you deal with the assignment problems, where the objective function is to be
                                       maximized?

                                   4.  What is an unbalanced assignment problem? Explain with the help of an example.
                                   5.  How is the Hungarian method applied for obtaining a solution if the matrix is rectangular?

                                   Problems

                                   6.  A manufacturer of garments plans to add 4 regional warehouses to meet increased demand.
                                       The following bids in lakhs of rupees have been for construction of the warehouses.

                                                                                Warehouse
                                              Contractor
                                                                  A             B           C           D
                                                  1               30            27          31         39
                                                  2               28            18          28         37
                                                  3               33            17          29         41
                                                  4               27            18          30         43
                                                  5               40            20          27         36

                                       Explain why each warehouse contract cannot simply be given to the contractor who bids
                                       cheapest. How will you then determine the optimal contract?
                                   7.  5 operators have to be assigned to 5 machines. The assignment costs are given in the table.

                                                                               Machine
                                             Operator         I           II        III       IV        V
                                               A              5            5         -         2         6
                                                B             7            4         2         3         4
                                                C             9            3         5         -         3
                                               D              7            2         6         7         2
                                                E             6            3         7         9         1

                                       Operator A cannot operate machine II and operator C cannot operate machine IV. Find the
                                       optimal assignment schedule.














          170                               LOVELY PROFESSIONAL UNIVERSITY
   170   171   172   173   174   175   176   177   178   179   180