Computation Section
Process Flow Analysis
 - Optimization Models
The Project Worksheet contains a button labeled Build LP/IP model. Pressing this button shows the dialog below.

Three options are available. The first produces a linear programming model with variables for the production level of each product. It computes the optimum product mix with constraints on the total resources used.

The second is also a linear programming model that adds to the production variables, variables that specify the time on each resource and the amounts of each raw material. It includes constraints on the amounts of raw materials and the amounts of resources available. It determines the optimum product mix with these added constraints.

The third is a mixed integer-linear programming model that also includes integer variables for the number of each resource type (machine type). It computes the optimum number of resources (machines) that should used for the system.

The objective in each case is to maximize the net income. The solutions obtained by solving the mathematical programming model are automatically placed on the Project worksheet.

The models use the Math Programming add-in, so that add-in must be installed to proceed. A solver add-in must also be available, either the Excel Solver or the Jensen LP/IP solver that is available from this site. The solver is chosen on the Linear Model dialog which appears after clicking the OK button on the dialog above. If the Excel Solver is used, be sure to connect to the Solver by selecting Solver from the Tools menu before trying to create a model. This establishes a connection to the add-in. Modeling will fail if the connection is not established.

Click the links at the left to learn about the three models.

Return to Top

tree roots

Operations Management / Industrial Engineering
by Paul A. Jensen
Copyright 2004 - All rights reserved

Next Page