the paper discusses the location-allocation model for logistic networks and distribution centers through considering uncertain parameters. in real-world cases, demands and transshipment costs change over the period of the time. this may lead to large cost deviation in total cost. scenario based robust optimization approaches are proposed where occurrence probability of each scenario is not know...

today, due to the direct and reverse logistics plays an important role in reducing the costs in supply chain. in this paper, in order to provide a closed-loop supply chain network including supply centers, production, distribution, collection, recycling and disposal of a used linear mixed integer programming. this paper to consider multi-period and multi-product in multi-level supply chain and ...

We focus on a three-stage supply chain problem for fast moving consumer goods including a supplier, a manufacturer and customers. There are different orders over identical cycles, to be processed in production site. The problem is to find a joint cyclic schedule of raw material procurement and job scheduling minimized the total cost comprised of raw material ordering cost and holding cost, prod...

mitochondrial respiration is a complex process which its biochemistry is often poorly understood by undergraduate students when explained in toxicology lectures. the use of experiments to reinforce their knowledge is important, but not always possible because of low teaching budgets. therefore, a low cost model, made using water, oil, styrofoam and modeling clay, is presented here to simulate t...

in this paper, the distribution network for multi-level supply chain has been studied. products produced in factories are sent to customers through warehouses and distribution centers based on specific demands. warehouses as holding inventory facilities are located close to factories and the distribution centers are placed in the most accessible locations for services near customers. each item ...

background: air pollution in tehran, capital of iran is responsible for several diverse negative effects. it has been estab­lished that air pollution can affect human health. these health effects include increased hospital admissions due to the ex­acerba­tion of cardiac and respiratory diseases, as well as symptoms such as headache, cough, eye irritation, nausea, sputum and even death in the mo...

replacement of a tractor is an influential factor affecting timely farm operation. the accurate prediction of repair and maintenance costs is essential to selection of a replacement model. this study used empirical data for 60 two-wheel drive (2wd) tractors from astan ghods-e razavi agroindustry. the types and numbers of tractors used were the massey ferguson 285 (17), fiat (10), john deere 314...

with the growth in customers’ demand diversification, mixed-model u-lines (mmul) have acquired increasing importance in the area of assembly systems. there are generally two different approaches in the literature for balancing such systems. some researchers believe that since the types of models can be very diverse, a balancing approach without simultaneously sequencing of models will not yield...

The objective of this research is to develop a turbine blade investment casting cost advisor model to assist a blade designer in decision-making in a concurrent engineering environment. It is a microcomputer based cost estimating system that employs a manufacturing knowledge base. The concept of the manufacturing process for blade production by the investment casting method is used to develop t...

The Hotelling's  control chart, is the most widely used multivariate procedure for monitoring  two or more related quality characteristics, but it’s power lacks the desired performance in detecting small to moderate shifts. Recently, the variable sampling intervals (VSI) control scheme in which the length of successive sampling intervals is determined upon the preceding values has been proved t...