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...

A different approach to the capacitated single allocation hub location problem is presented. Instead of using capacity constraints to limit the amount of flow that can be received by the hubs, we introduce a second objective function to the model (besides the traditional cost minimizing function), that tries to minimize the time to process the flow entering the hubs. Two bi-criteria single allo...

abstract in current study, an irrigation examination and acquisition of environmental water in kor-river fields, that is dominated from doroudzan dam to bakhtegan lake, was done by an integrated economy-environmental model. the model was considered by economic, hydrologic and agronomic components. in the economic component, an optimal harvesting of water was done using non-linear programming in...

Vendor managed inventory is a continuous replenishment program that is designed to provide major cost saving benefits for both vendors and retailers. Previous research on this area mainly included single objective optimization models where the objective is to minimize the total supply chain costs or to maximize the total supply chain benefits. This paper presents a bi-objective mathematical mod...

Instabilities of a thin viscous film flowing down a uniformly heated plane are investigated in this study. The heating generates a surface tension gradient that induces thermocapillary stresses on the free surface. Thus, the film is not only influenced by gravity and mean surface tension but also the thermocapillary force is acting on the free surface. Moreover, the heat transfer at the free su...

this paper presents a multi-objective linear programming model for disaster blood supply chain in some periods of time after disaster. this model assist to determine the quantity and location of facilities and also how to allocate blood to facilities. in this study, a three-level model is described, while blood is collected from temporary and permanent facilities and sent to blood center. blood...

The global optimization of constrained Non-Linear Bi-Objective Optimization problems (NLBOO) aims at covering their Pareto-optimal front which is in general a manifold in R. Continuation methods can help in this context as they can follow a continuous component of this front once an initial point on it is provided. They constitute somehow a generalization of the classical scalarizing framework ...