in this paper, a mathematical method is proposed to formulate a generalized ordering problem. this model is formed as a linear optimization model in which some variables are binary. the constraints of the problem have been analyzed with the emphasis on the assessment of their importance in the formulation. on the one hand, these constraints enforce conditions on an arbitrary subgraph and then g...

Increasing economy’s resistance against the menace of sanctions, various risks, shocks, and internal and external threats are one of the main national policies which can be implemented through bank investments. Investment project selection is a complex and multi-criteria decision-making process that is influenced by multiple and often some conflicting objectives. This paper studies portfolio inve...

This paper proposes a new mixed-integer model for the multi-skill resource-constrained project scheduling problem (MSRCPSP). The interactions between workers are represented as undirected networks. Therefore, for each required skill, an undirected network is formed which shows the relations of human resources. In this paper, community detection in networks is used to find the most compatible wo...

fuzzy linear programming models and methods has been one ofthe most and well studied topics inside the broad area of soft computing. itsapplications as well as practical realizations can be found in all the real worldareas. in this paper a basic introduction to the main models and methods infuzzy mathematical programming, with special emphasis on those developedby the authors, is presented. as ...

Much combinatorial optimisation problems constitute a nonpolynomial (NP) hard optimisation problem, i.e., they can not be solved in polynomial time. One such problem is finding the shortest route between two nodes on a graph. Meta-heuristic algorithms such as A∗ along with mixed-integer programming (MIP) methods are often employed for these problems. Our work demonstrates that it is possible to...

Today, generation and transmission expansion planning (G&TEP) to meet potential load growth is restricted by reliability constraints the presence of uncertainties. This study proposes constrained method for integrated renewable energy sources considering fault current limiter (FCL) placement sizing N-1 security. Moreover, an approach dealing with uncertain events adopted. The proposed model...

A rescheduling algorithm for trains on a single-track railway was developed in case of disturbances that would cause conflicts between trains. This is based mixed integer linear programming (MILP) with speed-up routines. The model considers station capacities explicitly (i.e., the number available tracks meeting and overtaking operations). Because too hard solvers (CPLEX this study) to tackle, ...

In this paper, we are discussing a research project aiming to optimize the scheduling of production orders within real application in packaging field. As first approach, model problem as an extended version hybrid and flexible flowshop with precedence constraints, parallel machines, sequence-dependent setups. The optimization objective considered is minimization total tardiness. To tackle probl...