The recent efforts to mount an R&D response public health emergencies of international concern have led the formation what we term a biochemical infrastructure vaccine development and production. In principle, this is expected not only curtail existing pandemics but also anticipate contain yet-to-emerge future threats. Critically, by nature its geographical distribution technical modularity, th...

This paper describes a genetic algorithm approach to the dynamic job shop scheduling problem with jobs arriving continually. Both deterministic and stochastic models of the dynamic problem were investigated. The objective functions examined were weighted flow time, maximum tardiness, weighted tardiness, weighted lateness, weighted number of tardy jobs, and weighted earliness plus weighted tardi...

the most important environmental pollutant in steel industry is air pollution due to the process of its products. optimise sitting for this industry, in a great extend will prevent pollutants and emissions. khorasan steel company is located near some populous villages and three rivers. it is necessary to perform an investigation for providing abatement and control of air pollution, in time of p...

The objective of this paper is to propose a scheduling problem for multiple automated guided vehicles (AGVs) in a manufacturing system. Considering the due date of AGVs requiring for material handling among shops in a job shop layout, their earliness and tardiness are significant in satisfying the expected cycle time and from an economic view point. Earliness results in AGVs waiting and tardine...

We evaluate two alternative models of international trade in differentiated products. An increasing returns model where varieties are linked to firms predicts home market effects: increases in a country’s share of demand cause disproportionate increases in its share of output. In contrast, a constant returns model with national product differentiation predicts a less than proportionate increase...

Dispatching rules are widely used to dynamically schedule the operations in a shop. Their efficiency depends on the performance criteria of interest. One of the most important objectives to deal with in a manufacturing system is the tardiness which can be measured through several performance measures. This paper proposes an effective procedure to estimate the first two central moments (i.e., th...

The advantages of the TOC (Theory of Constraints) philosophy have been extensively documented in the literature since its introduction during the 80s. At the operational level, TOC is implemented by means of the well-known DBR (Drum-Buffer-Rope) production control system. In a multiproduct manufacturing environment, the performance of DBR is greatly affected by the dispatching rules employed in...

The objective of this paper is to propose a scheduling problem for multiple automated guided vehicles (AGVs) in a manufacturing system. Considering the due date of AGVs requiring for material handling among shops in a job shop layout, their earliness and tardiness are significant in satisfying the expected cycle time and from an economic view point. Earliness results in AGVs waiting and tardine...

Many optimization problems in the industrial engineering world, particularly in manufacturing systems, are very complex in nature and difficult to solve by conventional optimization techniques. The use of formal approaches is frequently limited owing to the complexity of the models or algorithms. In this paper, a novel approach is proposed for large scale single machine weighted tardiness probl...