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A branch-and-cut for the Non-Disjoint m-Ring-Star Problem

Pierre Fouilhoux, Aurélien Questel (2014)

RAIRO - Operations Research - Recherche Opérationnelle

In this article we study the realistic network topology of Synchronous Digital Hierarchy (SDH) networks. We describe how providers fulfill customer connectivity requirements. We show that SDH Network design reduces to the Non-Disjoint m-Ring-Star Problem (NDRSP). We first show that there is no two-index integer formulation for this problem. We then present a natural 3-index formulation for the NDRSP together with some classes of valid inequalities that are used as cutting planes in a Branch-and-Cut...

A continuous optimization model for a joint problem of pricing and resource allocation

Mustapha Bouhtou, Guillaume Erbs (2009)

RAIRO - Operations Research

This paper investigates the problem of maximizing the revenue of a telecommunications operator by simultaneously pricing point-to-point services and allocating bandwidth in its network, while facing competition. Customers are distributed into market segments, i.e., groups of customers with a similar preference for the services. This preference is expressed using utility functions, and customers choose between the offers of the operator and of the competition according to their utility. We model...

A Global Stochastic Optimization Method for Large Scale Problems

W. El Alem, A. El Hami, R. Ellaia (2010)

Mathematical Modelling of Natural Phenomena

In this paper, a new hybrid simulated annealing algorithm for constrained global optimization is proposed. We have developed a stochastic algorithm called ASAPSPSA that uses Adaptive Simulated Annealing algorithm (ASA). ASA is a series of modifications to the basic simulated annealing algorithm (SA) that gives the region containing the global solution of an objective function. In addition, Simultaneous Perturbation Stochastic Approximation (SPSA)...

A hybrid genetic algorithm for a dynamic logistics network with multi-commodities and components

Peng-Sheng You, Yi-Chih Hsieh, Hisn-Hung Chen (2011)

RAIRO - Operations Research

Various topics related to reverse logistics have been discussed over the years. Most of them have assumed that facilities are kept open once they are established, and no returned products or recovery parts are stocked in intermediate recycling stations. However, firms may have the right to repeatedly open or close their facilities according to their economic benefits if they can acquire their facilities by lease. It also turns out that intermediate recycling stations like collection centers...

A hybrid genetic algorithm for a dynamic logistics network with multi-commodities and components

Peng-Sheng You, Yi-Chih Hsieh, Hisn-Hung Chen (2011)

RAIRO - Operations Research

Various topics related to reverse logistics have been discussed over the years. Most of them have assumed that facilities are kept open once they are established, and no returned products or recovery parts are stocked in intermediate recycling stations. However, firms may have the right to repeatedly open or close their facilities according to their economic benefits if they can acquire their facilities by lease. It also turns out that intermediate recycling stations like collection centers...

A note on the optimal portfolio problem in discrete processes

Naoyuki Ishimura, Yuji Mita (2009)

Kybernetika

We deal with the optimal portfolio problem in discrete-time setting. Employing the discrete Itô formula, which is developed by Fujita, we establish the discrete Hamilton–Jacobi–Bellman (d-HJB) equation for the value function. Simple examples of the d-HJB equation are also discussed.

A RED modified weighted moving average for soft real-time application

Joanna Domańska, Adam Domański, Dariusz R. Augustyn, Jerzy Klamka (2014)

International Journal of Applied Mathematics and Computer Science

The popularity of TCP/IP has resulted in an increase in usage of best-effort networks for real-time communication. Much effort has been spent to ensure quality of service for soft real-time traffic over IP networks. The Internet Engineering Task Force has proposed some architecture components, such as Active Queue Management (AQM). The paper investigates the influence of the weighted moving average on packet waiting time reduction for an AQM mechanism: the RED algorithm. The proposed method for...

Airspace sectorization with constraints

Huy Trandac, Philippe Baptiste, Vu Duong (2005)

RAIRO - Operations Research - Recherche Opérationnelle

We consider the Airspace Sectorization Problem (ASP) in which airspace has to be partitioned into a given number of sectors, each of which being assigned to a team of air traffic controllers. The objective is to minimize the coordination workload between adjacent sectors while balancing the total workload of controllers. Many specific constraints, including both geometrical and aircraft related constraints are taken into account. The problem is solved in a constraint programming framework. Experimental...

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