# Problema depozitelor

Trimis la data: 2014-09-17 Materia: Management Nivel: Facultate Pagini: 4 Nota: / 10 Downloads: 0
Autor: Tudor Costin Dimensiune: 18kb Voturi: Tipul fisierelor: doc Acorda si tu o nota acestui referat:
vezi mai multe detalii vezi mai putine detalii
Raporteaza o eroare
An electronics company decides to locate a number of depots in the Twente region, to enable a timely delivery of goods to customers. To place a depot there are five candidate cities. These cities also represent the customers of the company. The company wants to place the depot(s) in one or more cities in such a way, that total depot and transportation costs are minimized. The following table specifies the annual demand for products, and the fixed annual depot costs for each of the cities. The data is based on estimates.

The central research question is:
In which cities should depots be located in order to minimize annual costs (= depot costs + transport costs)?
We will distinguish two versions of this problem. In Assignment 1.1 we consider the case without capacity restrictions on the depots. In Assignment 1.2 we consider the case with capacity restrictions on the depots. Assignment 1.3 consists of some theory questions; try to prepare these at home (i.e., use your time during the exercise class for assignments 1.1 and 1.2).

For this assignment we use the mathematical programming software "OMST_LP_Shell". Before you start, make sure you copy all the files to a directory.Warning: make sure to save your files before you log out of the terminal server. The assignments must be handed in through Blackboard.Assignment 1.1. (A): no depot capacity restrictions
We will study two ways to model this problem.(first model option) Demonstrate that the problem can be formulated straightforwardly as an integer linear program (ILP), with the variables Xd (0-1, indicates whether depot d is opened) and Ysd (non-negative integer, indicates the number of product units delivered to city s from depot d)

(i) Write down a qualitative model formulation, i.e., describe the parameters, variables, restrictions and objective.
(ii) Write down an ILP formulation of the problem in (i) (i.e., not in the OMST_LP_Shell!).(iii) Write down the corresponding LP relaxation (i.e., not in the OMST_LP_Shell).

(iv) Formulate the problem in (ii) in the 'OMST_LP_Shell'. Use the file 'depotlocatie1a.olp', in which the required sets, parameters and data have already been defined. Determine the optimal solution. What depot(s) do you find? From what depot is each city delivered?
(v) What is the solution of the LP-relaxation? Is it feasible? How can you interpret / use the LP relaxation solution?

• pag. 1
• pag. 2
• pag. 3
• pag. 4

Nota explicativa
Referatele si lucrarile oferite de Referate.ro au scop educativ si orientativ pentru cercetare academica.

Iti recomandam ca referatele pe care le downloadezi de pe site sa le utilizezi doar ca sursa de inspiratie sau ca resurse educationale pentru conceperea unui referat nou, propriu si original.

Referat.ro te invata cum sa faci o lucrare de nota 10!