The EOQ repair and waste disposal model with switching costs

Short-term scheduling for multiproduct batch chemical plants

Bellman’s equation is widely used in solving stochastic optimal control problems in a variety of applications including investment planning, scheduling problems and routing problems. Building on Markov decision processes for stationary policies, we present a new proof for Bellman’s equation of optimality. Our proof rests its case on the availability of an explicit model of the environment that embodies transition probabilities and associated costs.

On the Bellman's principle of optimality

This review is concerned with problems of industry and industrialization in the developing countries where OR methods are used for their solution. A matrix showing the geographic regions of application and the techniques used is given for 230 selected articles published over the last two decades. The objective of the review is to examine the extent to which OR applications in these areas are relevant to the development problems of the developing countries and whether the existing techniques and methodologies are suitable to tackle such problems. Finally, the research gaps are identified and research efforts necessary to bridge these gaps are suggested.

Applications of operational research in industry and industrialization in the developing countries: A review

To satisfy the increasing trend of diverse customer product needs and to cope with internal capacity constraints, the management of current manufacturing firms must plan multiproduct batch fabrication and be able to reduce its completion time and/or smooth overall production schedules Furthermore, because of various unforeseen problems in real fabrication processes, defective items may be randomly produced These items need to be identified and separated from perfect stocks to maintain the required quality level Inspired by these facts, we explore a multiproduct economic manufacturing quantity (EMQ) problem considering rework and overtime options An exact model is built to study the characteristics of the problem that have not yet been explicitly examined in the literature This newly developed model employs a mathematical technique together with differential calculus to not only obtain the total cost function of the system, but also to prove its convexity and determine the optimal cycle time that minimizes the total system cost A numerical illustration is provided to demonstrate its applicability Subsequently, the impact of overtime and rework on the optimal solution, relevant cost variables, and the completion time of batch fabrication, machine utilization, can be obtained This information on the cost-effectiveness of problem characteristics is valuable in facilitating managerial decisions

Determining the optimal cycle length for a multiproduct EMQ problem considering rework and overtime options

The single facility multiple products scheduling problem is formulated into a multiperiod mathematical programming model with zero-one variables. An algorithm to solve the scheduling problem by using the concept of state vectors of dynamic programming is described. An example of application of the model and the algorithm is also presented. It has been found that a suitable selection of a state vector reduces greatly the dimensionality of the problem

https://link.springer.com/content/pdf/10.1057%2Fjors.1980.149.pdf

H. K. Leong

Papers

A Method for Single Facility Multiple Products Scheduling