Often, extensions to both are required. Conference of the Operational Research Society, Lancaster, England, September 8, 1998. Although modeling systems for optimization are by now well established, they continue to admit significant improvements. This presentation will survey a variety of extensions, for such purposes as expressing complementarity conditions, linking to databases, manipulating solver statuses and analyses, and providing remote access to model translators and solvers. Prospective extensions for better supporting stochastic programming and combinatorial optimization will also be touched upon.
Planning is the longer-term counterpart of scheduling in managing a steelmaking operation.
After brief remarks on the desirability of optimization in planning generally, this presentation surveys current technologies for building and maintaining planning optimization models. The fundamental characteristics of steelmaking are shown to be well suited to the creation of a generic model, which is in turn readily specialized to particular situations. The practical limits of size and complexity in such a model have increased substantially in recent years, due to the interaction of faster computers with improved algorithmic technology and more advanced optimization languages and environments. Examples of both approaches will be described and contrasted. We describe two approaches from our current research, one employing an algebraic modeling language and the other a 'toolkit' for network optimization.