Service restorability is a key requirement in optical networks. This means that when wavelength paths are established, both a primary path and a secondary disjoint path have to be set-up, with the secondary path being used for service restoration upon primary path failure. The secondary path may possibly be shared for efficiency. The need for secondary paths imposed by the restorability require...

In this paper, a multi-perspective decision support system (MP-DSS)‎ ‎to design hierarchical public transportation network is developed‎. ‎Since this problem depends on different perspectives‎, ‎MP-DSS consists of two sub-systems with macro and micro sub-systems based on travel information‎, ‎land use and expert knowledge‎. ‎In the micro sub-system‎, ‎two sub-modules are developed considering o...

The paper addresses a multi-item, multi-plant lot-sizing problem with transfer costs and capacity constraints. The problem is reformulated according to a multi-commodity flow formalism, and decomposed, through Lagrangean relaxation, into a master facility location problem and a slave minimal cost multi-commodity flow problem. The decomposition framework gives rise in a natural way to the design...

We consider the problem of finding a feasible single-commodity flow in a strongly connected network with fixed supplies and demands, provided that the sum of supplies equals the sum of demands and the minimum arc capacity is at least this sum. A fast algorithm for this problem improves the worst-case time bound of the Goldberg-Rao maximum flow method[3] by a constant factor. Erlebach and Hageru...

The scale of the global chemical industry is enormous: in 2003, the total value of global production exceeded US$1.7 trillion. International logistics is especially crucial to the high-value chemicals industry, since raw materials sources, production facilities, and consumer markets are distributed globally. Fluctuating demand, imbalanced trade flows, and expensive transportation equipment nece...

In the maximum flow network interdiction problem, an attacker attempts to minimize the maximum flow by interdicting flow on the arcs of network. In this paper, our focus is on the nodal interdiction for network instead of the arc interdiction. Two path inequalities for the node-only interdiction problem are represented. It has been proved that the integrality gap of relaxation of the maximum fl...

A simulation approach of a smart grid by cooperative bargaining is presented in this paper. Each participant of the smart grid determines its optimal schedule to meet its power and heating demand at minimal costs employing solar panels, fuel cells and batteries. This is done by solving a quadratic optimisation problem which takes the energy prices and the available devices into account. The ene...

In this paper we introduce the lexicographically minimum load linear programming problem and we provide a polynomial approach followed by the proof of correctness. This problem has applications in numerous areas where it is desirable to achieve an equitable distribution or sharing of resources. We consider the application of our technique in the problem of lexicographically minimum load in capa...

Abstract. We address the two-commodity maximum flow problem on undirected networks. As a result of a change of variables, we introduce a new formulation that solves the problem through classical maximum flow techniques with only one-commodity. Therefore, a general strategy, based on this change of variables, is defined to deal with other undirected multi-commodity problems. Finally, we extend t...