HLP (hub location problem) tries to find locations of hub facilities and assignment of nodes to extended facilities. Hubs are facilities to collect, arrange, and distribute commodities in telecommunication networks, cargo delivery systems, etc. Hubs are very crucial and their inaccessibility impresses on network whole levels. In this paper, first, total reliability of the network is defined bas...

This paper considers a time dependent(the travel time is not constant throughout the day) pollution routing problem (TDPRP), which aids the decision makers in minimizing travel time, toll cost and emitted pollution cost.  In complexity of urban areas most of the time one point is accessible from another with more than one edge. In contrast to previous TDPRP models, which are designed with only ...

Scheduling for job shop is very important in both fields of production management and combinatorial op-timization. However, it is quite difficult to achieve an optimal solution to this problem with traditional opti-mization approaches owing to the high computational complexity. The combination of several optimization criteria induces additional complexity and new problems. In this paper, we pro...

Model building is a fragile and complex process especially in the context of real cases. Each real case problem has its own characteristics with new concepts and conditions. A correct model should have some essential characteristics such as: being compatible with real conditions, being of sufficient accuracy, being logically traceable and etc. This paper discusses how to build an efficient mode...

Almost all of electric utility companies are planning to improve their management automation system, in order to meet the changing requirements of new liberalized energy market and to benefit from the innovations in information and communication technology (ICT or IT). Architectural design of the utility management automation (UMA) systems for their IT-enabling requires proper selection of ...

Setiap perusahaan selalu berusaha dapat memperoleh keuntungan yang besar. Salah satu cara dilakukan oleh adalah menekan biaya dikeluarkan. proses memerlukan besar logistik dan dua per tiga ini berasal dari persediaan transportasi. Permasalahan transportasi pada perspektif supply chain perlu dipertimbangkan bersama agar memberikan hasil optimal. dimodelkan dalam inventory routing problem (IRP). ...

This paper presents a new mathematical model for a bi-objective job shop scheduling problem with sequence-dependent setup times that minimizes the weighted mean completion time and the weighted mean tardiness time. For solving this multi-objective model, we develop a fuzzy multi-objective linear programming (FMOLP) model. In this problem, a proposed FMOLP method is applied with respect to the o...

The multi-level programming problems are attractive for many researchers because of their application in several areas such as economic, traffic, finance, management, transportation, information technology, engineering and so on. It has been proven that even the general bi-level programming problem is an NP-hard problem, so the multi-level problems are practical and complicated problems therefo...