In this paper, a supplier-retailer transportation system is investigated as a two-echelon environment. There is a single location in each echelon; the unique supplier at the first echelon has to replenish the retailer's warehouse at the second echelon. By the way, the shortage situation should be avoided. For this situation, a model is provided based on the traditional EOQ model. The inventory ...

Safety risk study on road transportation of hazardous chemicals is a reliable basis for the government to formulate transportation planning and preparing emergent schemes, but also is an important reference for safety risk managers to carry out dangerous chemicals safety risk managers. Based on the analysis of the transport safety risk of dangerous chemicals at home and abroad, this paper studi...

The transportation of hazardous goods represents an economic activity whose consequences can have serious impact on the safety of transportation, the environment and human health. With the aim of reviewing the elements that affect the activity, this article presents a model for the transportation of hazardous goods of which, generally, there are two forms: the theoretical model for the transpor...

In this paper, developed a new multi-product, multi-period, and multi-level closed-loop green supply chain planning model under uncertain conditions. The formulated model consists of five objective functions, which minimize the cost of the supply chain, minimize the CO2 emission of transportation vehicles, maximize the reliability of manufacturing and distribution centers, maximize t...

Freight and passenger transport are two main functions of the infrastructure and transportation networks in each country. It is required to efficiently utilize the transportation infrastructures to increase transportation-related performance measures. In this study, data envelopment analysis (DEA) model is used to evaluate performance of the Iranian provinces from the freight and passenger tran...

in this paper, the staff assignment problem considering cross-training of caregivers in health care systems is addressed to determine which staff should be cross-trained for each service and how they should be assigned to services. a bi-objective non-linear mathematical programming model is presented where the first objective function aims to minimize workload balancing, cross-training as well ...

this study aims to minimize the total cost of a four-echelon supply chain including suppliers, an assembler, distributers, and retailers. the total cost consists of purchasing raw materials from the suppliers by the assembler, assembling the final product, materials transportation from the suppliers to the assembler, product transportation from the assembler to the distributors, product transpo...