Genetic programming is an automatic technique for producing a computer program that solves, or approximately solves, a problem. This chapter reviews several recent examples of human-competitive results produced by genetic programming. The examples all involve the automatic synthesis of a complex structure from a high-level statement of the requirements for the structure. The illustrative result...

The lot–sizing polytope is a fundamental structure contained in many practical production planning problems. Here we study this polytope and identify facet–defining inequalities that cut off all fractional extreme points of its linear programming relaxation, as well as liftings from those facets. We give a polynomial– time combinatorial separation algorithm for the inequalities when capacities ...

During the last decade, the mode of operation of many centralized computer installations has been significantly changed by the widespread use of remote job entry (RJE) . facilities. The increasing usage of remote work stations presents the analyst a significant problem in sizing remotes to efficiently handle the flow of jobs. Currently, few, if any, tools exist to aid the analyst in this area. ...

1. Abstract In structural sizing optimization problems the aim is to minimize an objective function under certain constraints. The design variables of the optimization problem are generally discrete and belong to certain discrete sets. In the context of the present work the design set is implemented and efficiently treated as a database that contains the required geometric properties for all de...

Abstrac t-Based on an incremental path search algorithm, this paper addresses the problem of performance driven path classification by sizing selected gates on the shortest and the longest identified paths of the circuit. Delay and power/area constraints are managed using circuit path sizing alternatives defined through a realistic evaluation of gate power and delay. Implemented in the POPS too...

Multi-item capacitated lot-sizing problems are reformulated using a class of valid inequalities, which are facets for the single-item uncapacitated problem. Computational results using this reformulation are reported, and problems vnth up to 20 items and 13 periods have been solved to optimality using a commercial mixed integer code. We also show how the valid inequalities can easily be generat...

This paper presents a population-sizing model for the entropy-based model building in genetic algorithms. Specifically, the population size required for building an accurate model is investigated. The effect of the selection pressure on population sizing is also incorporated. The proposed model indicates that the population size required for building an accurate model scales as Θ(m logm), where...

We present the development of a semi-analytical algorithm for optical particle sizing in disperse media. The algorithm is applied to the specific case of water clouds. However, it can be extended with minor modifications to other types of light-scattering medium. It is assumed that the optical thickness tau of the medium is large and the probability of photon absorption beta is small. Thus the ...

In this paper, the problem of lot sizing, scheduling and delivery of several items in a two-stage supply chain over a finite planning horizon is studied. Single supplier via a flexible flow line production system (FFL), produces several items and delivers them directly to an assembly facility. Based on basic period (BP) strategy, a new mixed zero-one nonlinear programming model has been develop...

Material requirements planning (MRP) is an old field but still now plays an important role in coordinating replenishment decision for materials/components of complex product structure. As the key part of MRP system, the multilevel lot-sizing (MLLS) problem concerns how to determine the lot sizes for producing/procuring multiple items at different levels with quantita‐ tive interdependences, so ...