The Role of Software in Optimization and Operations Research

OPTIMIZATION AND OPERATIONS RESEARCH – The Role of Software in Optimization and Operations Research - Harvey J.
Greenberg
6.3. Discourse
Figure 10: Formulation Component of IMPS
The objective of a discourse model is to communicate with a user, to which we add: in a
manner that is most natural for him or her. Natural language includes both text and
graphics. Algebraic and functional forms are what we are used to seeing in textbooks,
but constrained logic programming (CLP) is changing that. We now enlarge our
expressive powers to include many mathematical and logical forms.
The idea is to have one fundamental structure from which many different views can be
constructed at the will of the analyst. Some of the early ideas from neural networks and
concept graphs have not quite fulfilled their potential in discourse for optimization. We
primarily rely on syntax, but there is a growing development of visualization,
particularly for analysis support.
6.4. Analysis
So far, intelligent analysis support has been rule-driven. To illustrate, we shall show
some substructures found by ANALYZE, followed by a hypothetical discourse. Figure
11 shows a portion of a linear program that traces the flow of activities that generate
baseload electricity in a particular region. There are 26 activities that could generate this
electricity. Of these, 13 have zero reduced cost, including 9 basic activities. Each of the
13 activities is a candidate for being in a margin-setting path, so other paths were traced.
Each of the 12 paths must be blocked by some activity at bound; otherwise, a less
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