Topics on "Operational Research" Mar. 2007, IST
Linear Programming, an introduction
MIGUEL A. S. CASQUILHO IST, Universidade Técnica de Lisboa, Ave. Rovisco Pais, IST; 1049-001 Lisboa, Portugal
Linear Programming is presented at an introductory level, mainly from the book by Hillier and Lieberman [2005], abridged and adapted to suit the objectives of the “Operational Research” course. It begins with segments of its third chapter.
Key words: linear programming; simplex method.
I. Fundamentals and scope
Based on a prototype example, Linear Programming is presented, as well as the simplex method of resolution. This method was first presented by G. B. Dantzig in 1947 [MacTutor, 2007]. The text is based on the book by Hillier and Lieberman [2005], and begins with segments of the third chapter of the book.
II. Explanation of the simplex method 3 Introduction to Linear Programming
(H&L 25)
The development of linear programming has been ranked among the most important scientific advances in the mid-20.th century, and we must agree with this assessment. Its impact since just 1950 has been extraordinary. Today it is a standard tool that has saved many thousands or millions of dollars for most companies or businesses of even moderate size in the various industrialized countries of the world; and its use in other sectors of society has been spreading rapidly.
3.1 Prototype example
(H&L 26)
Table 1 Data for the Wyndor Glass Co. problem
Plant A B C Profit per batch Production time per batch (h) Product 1 2 1 0 0 2 3 2 3 000 5 000 Production time available per week (h) 4 12 18
x1 = number of batches of product 1 produced per week x2 = number of batches of product 2 produced per week Z = total profit per week (in $1000) from producing these two products
M. Casquilho is Assistant Professor in the Department of Chemical and Biological Engineering, Instituto Superior Técnico, Universidade Técnica de Lisboa. E-mail address: mcasquilho@ist.utl.pt.
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