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A backstepping approach to ship course control

Anna Witkowska, Mirosław Tomera, Roman Smierzchalski (2007)

International Journal of Applied Mathematics and Computer Science

As an object of course control, the ship is characterised by a nonlinear function describing static manoeuvring characteristics that reflect the steady-state relation between the rudder deflection and the rate of turn of the hull. One of the methods which can be used for designing a nonlinear ship course controller is the backstepping method. It is used here for designing two configurations of nonlinear controllers, which are then applied to ship course control. The parameters of the obtained nonlinear...

A discrete-time approximation technique for the time-cost trade-off in PERT networks

Amir Azaron, Masatoshi Sakawa, Reza Tavakkoli-Moghaddam, Nima Safaei (2007)

RAIRO - Operations Research


We develop a discrete-time approximation technique dealing with the time-cost trade-off problem in PERT networks. It is assumed that the activity durations are independent random variables with generalized Erlang distributions, in which the mean duration of each activity is a non-increasing function of the amount of resource allocated to it. It is also assumed that the amount of resource allocated to each activity is controllable. Then, we construct an optimal control problem with three conflicting...

A factor graph based genetic algorithm

B. Hoda Helmi, Adel T. Rahmani, Martin Pelikan (2014)

International Journal of Applied Mathematics and Computer Science

We propose a new linkage learning genetic algorithm called the Factor Graph based Genetic Algorithm (FGGA). In the FGGA, a factor graph is used to encode the underlying dependencies between variables of the problem. In order to learn the factor graph from a population of potential solutions, a symmetric non-negative matrix factorization is employed to factorize the matrix of pair-wise dependencies. To show the performance of the FGGA, encouraging experimental results on different separable problems...

A fast Lagrangian heuristic for large-scale capacitated lot-size problems with restricted cost structures

Kjetil K. Haugen, Guillaume Lanquepin-Chesnais, Asmund Olstad (2012)

Kybernetika

In this paper, we demonstrate the computational consequences of making a simple assumption on production cost structures in capacitated lot-size problems. Our results indicate that our cost assumption of increased productivity over time has dramatic effects on the problem sizes which are solvable. Our experiments indicate that problems with more than 1000 products in more than 1000 time periods may be solved within reasonable time. The Lagrangian decomposition algorithm we use does of course not...

A finite-buffer queue with a single vacation policy: an analytical study with evolutionary positioning

Marcin Woźniak, Wojciech M. Kempa, Marcin Gabryel, Robert K. Nowicki (2014)

International Journal of Applied Mathematics and Computer Science

In this paper, application of an evolutionary strategy to positioning a GI/M/1/N-type finite-buffer queueing system with exhaustive service and a single vacation policy is presented. The examined object is modeled by a conditional joint transform of the first busy period, the first idle time and the number of packets completely served during the first busy period. A mathematical model is defined recursively by means of input distributions. In the paper, an analytical study and numerical experiments...

A heuristic column generation method for the heterogeneous fleet VRP

E. D. Taillard (2010)

RAIRO - Operations Research

This paper presents a heuristic column generation method for solving vehicle routing problems with a heterogeneous fleet of vehicles. The method may also solve the fleet size and composition vehicle routing problem and new best known solutions are reported for a set of classical problems. Numerical results show that the method is robust and efficient, particularly for medium and large size problem instances.

A Hybrid Approach Combining Local Search and Constraint Programming for a Large Scale Energy Management Problem

Haris Gavranović, Mirsad Buljubašić (2013)

RAIRO - Operations Research - Recherche Opérationnelle

This paper presents a heuristic approach combining constraint satisfaction, local search and a constructive optimization algorithm for a large-scale energy management and maintenance scheduling problem. The methodology shows how to successfully combine and orchestrate different types of algorithms and to produce competitive results. We also propose an efficient way to scale the method for huge instances. A large part of the presented work was done to compete in the ROADEF/EURO Challenge 2010, organized...

A hybrid approach for scheduling transportation networks

Mahjoub Dridi, Imed Kacem (2004)

International Journal of Applied Mathematics and Computer Science

In this paper, we consider a regulation problem of an urban transportation network. From a given timetable, we aim to find a new schedule of multiple vehicles after the detection of a disturbance at a given time. The main objective is to find a solution maximizing the level of service for all passengers. This problem was intensively studied with evolutionary approaches and multi-agent techniques, but without identifying its type before. In this paper, we formulate the problem as a classical one...

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 hybrid genetic algorithm for the vehicle routing problem with three-dimensional loading constraints

Lixin Miao, Qingfang Ruan, Kevin Woghiren, Qi Ruo (2012)

RAIRO - Operations Research

This paper addresses a Three-Dimensional Loading Capacitated Vehicle Routing Problem (3L-CVRP) which combines a three-dimensional loading problem and vehicle routing problem in distribution logistics. The problem requires the combinatorial optimization of a feasible loading solution and a successive routing of vehicles to satisfy client demands, where all vehicles must start and terminate at a central depot. In spite of its clear practical significance...

A hybrid genetic algorithm for the vehicle routing problem with three-dimensional loading constraints

Lixin Miao, Qingfang Ruan, Kevin Woghiren, Qi Ruo (2012)

RAIRO - Operations Research

This paper addresses a Three-Dimensional Loading Capacitated Vehicle Routing Problem (3L-CVRP) which combines a three-dimensional loading problem and vehicle routing problem in distribution logistics. The problem requires the combinatorial optimization of a feasible loading solution and a successive routing of vehicles to satisfy client demands, where all vehicles must start and terminate at a central depot. In spite of its clear practical significance...

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