In this paper we give a fast algorithm to generate all partitions of a positive integer n. Integer partitions may be encoded as either ascending or descending compositions for the purposes of systematic generation. It is known that the ascending composition generation algorithm is substantially more efficient than its descending composition counterpart. Using tree structures for storing the partitions of ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 11, no. 1, pp. 89-104, 2012]]>We formulate a deterministic HIV/AIDS model to theoretically investigate how counselling and testing coupled with the resulting decrease in sexual activity could affect the HIV epidemic in resource-limited communities. The threshold quantities are determined and stabilities analyzed. Theoretical analysis and numerical simulations support the idea that increase in the number of sexually inactive HIV positive individuals who voluntarily ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 1, pp. 31-55, 2011]]>To find the fuzzy optimal solution of fuzzy transportation problems it is assumed that the direct route between a source and a destination is a minimum-cost route. However, in actual application, the minimum-cost route is not known a priori. In fact, the minimum-cost route from one source to another destination may well pass through another source first. ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 2, pp. 163-180, 2011]]>We present a deterministic HIV/AIDS model with delay. We then extend the model by adjoining terms capturing stochastic effects. The intensity of the fluctuations in the stochastic system is analytically evaluated using Fourier transform methods. We carry out simulations to assess differences in the dynamical behavior of the deterministic and stochastic models. Simulation results show that they are no ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 2, pp. 181-191, 2011]]>Clustering remains one of the most difficult challenges in data mining. This paper proposes a new algorithm, CLAM, using a hybrid metaheuristic between VNS and Tabu Search to solve the problem of k-medoid clustering. The new technique is compared to the well-known CLARANS. Experimental results show that, given the same computation times, CLAM is more effective.

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 1, pp. 57-78, 2011]]>Consider the set S of points in the plane consisting of the ordered pairs (i, j), where 1 6 i 6 m and 1 6 j 6 n. A problem related to the study of segmentation evaluation of visual images concerns finding a permutation σ of the points of S for which the sum X s∈S d(s, σ(s)) ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 2, pp. 193-203, 2011]]>Design Rule Checking (DRC) in VLSI design involves checking if a given VLSI layout satisfies a given set of rules and reporting the violations if any. We propose data structures for reporting violations of the minimum extension rule in a query window of interest.

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 1, pp. 79-107, 2011]]>A matheuristic approach, where concepts from linear programming are integrated into an evolutionary algorithm, is proposed. It is tested on a problem arising in wireless sensor networks: a topology with minimum total power expenditure, that connects a source node to all the other nodes of the network, has to be identified. Experimental results are presented.

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 2, pp. 145-162, 2011]]>In this paper, we consider a trust region algorithm for unconstrained optimization problems. Unlike the traditional memoryless trust region methods, our trust region model includes memory of the past iteration, which makes the algorithm less myopic in the sense that its behavior is not completely dominated by the local nature of the objective function, but rather by a more global ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 2, pp. 109-118, 2011]]>We study the dual power management problem in wireless sensor networks. Given a wireless sensor network with two possible power levels (heigh and low) for each sensor, the problem consists in minimizing the number of sensors assigned heigh power while ensuring the connectivity of the network. We formulate the problem by a binary integer programming model to minimize the total ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 2, pp. 205-212, 2011]]>This paper deals with algorithms for detecting graph isomorphism (GI) properties. The GI literature consists of numerous research directions, from highly theoretical studies (e.g. defining the GI complexity class) to very practical applications (pattern recognition, image processing). We first present the context of our work and provide a brief overview of various algorithms developed in such disparate contexts. Compared ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 2, pp. 119-143, 2011]]>The positive hull of a finite set of vectors, , in d-dimensional space may or may not contain a lineality space . This article presents an algorithm that identifies the vectors of that belong to . This is done by means of a sequence of supporting hyperplanes because every supporting hyperplane of the positive hull of contains . Computational results show the effectiveness ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 10, no. 1, pp. 1-30, 2011]]>In this paper we propose a new procedure for classification based on a hybrid approach. The classification problem is solved by minimizing the distance between the components of each clusters and the centers of the clusters. The determination of the cluster centers is therefore a critical step in our approach and was addressed used the k-means algorithm. Once the ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 3, pp. 247-255, 2010]]>This paper proposes an algorithm to design a two-channel linear phase quadrature mirror filter (QMF) bank. The design problem is presented systematically as an unconstrained optimization that minimizes the weighted sum of error of transfer function of the filter bank at quadrature frequency, stopband energy and the passband error of a prototype filter (PF). A new method is developed ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 1, pp. 99-111, 2010]]>The topic of Gray codes for the set of compositions with non-negative integer parts has been studied by several authors. Klingsberg gave a non-recursive description of a Gray code for this set after the recursive version of Knuth. Recently, Walsh modified Klingsberg’s algorithm to find a Gray code which generates the set of all bounded compositions with non-...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 4, pp. 343-356, 2010]]>In this paper we introduce an optimization problem which involves maximization of the area of Voronoi regions of a set of points placed inside a circle. Such optimization goals arise in facility location problems consisting of both mobile and stationary facilities. Let ψ be a circular path through which mobile service stations are plying, and S be a set of ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 4, pp. 375-392, 2010]]>Polymers are compounds formed by the joining of smaller, often repeating, units linked by covalent bonds. The analysis of their sequence is a fundamental issue in many areas of chemistry, medicine and biology. Nowadays, the prevalent approach to this problem consists in using a mass spectrometry analysis that gives information about the molecular weights of the polymer and of its ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 3, pp. 213-232, 2010]]>Biochemical networks are a particular kind of biological networks which describe the cell metabolism and regulate various biological functions, from biochemical pathways to cell growth. The relationship between structure, function and regulation in complex cellular networks is still a largely open question. This complexity calls for proper mathematical models and methods relating network structure and functional properties. In this paper ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 1, pp. 19-37, 2010]]>This paper follows a word-document co-clustering model independently introduced in 2001 by several authors such as I.S. Dhillon, H. Zha and C. Ding. This model consists in creating a bipartite graph based on word fre- quencies in documents, and whose vertices are both documents and words. The created bipartite graph is then partitioned in a way that ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 2, pp. 131-147, 2010]]>The majority of visual impairments are related to retinal disorders. Therefore, techniques useful for early detection of retinal anomalies are of great interest for diagnosis and treatment of related pathologies. Optical Coherence Tomography (OCT) is a non-invasive technique that is becoming increasingly important in the analysis of human retina. This technique produces sections of a three dimensional reflectance map, ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 3, pp. 257-273, 2010]]>Predicting the native structure of proteins is one of the most challenging prob- lems in molecular biology. The goal is to determine the three-dimensional structure from the one-dimensional amino acid sequence. De novo prediction algorithms seek to do this by devel- oping a representation of the proteins structure, an energy potential and some optimization algorithm that finds the ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 2, pp. 181-194, 2010]]>In this paper we introduce a new scheduling scheme based on so called tri-directional scheduling strategy to solve the well known resource constrained project scheduling problem. In order to demonstrate the effectiveness of tri-directional scheduling scheme, it is incorporated into a priority rule based parallel scheduling scheme. Theoretical and numerical investigations show that the tri-directional scheduling scheme ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 4, pp. 357-373, 2010]]>In this paper we consider different concepts of causality in filtered probability spaces. Especially, we consider a generalization of a causality relationship “G is a cause of J within H ” which was first given by Mykland (1986) and which is based on Granger’s definition of causality (Granger, Econometrica 37:424–438, 1969). Then we apply this concept on weak ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 1, pp. 113-128, 2010]]>The modern systems biology approach to the study of molecular cellular biology, consists in the development of computational tools to support the formulation of new hypotheses on the molecular mechanisms underlying the observed cell behavior. Recent biotechnologies are able to provide precise measures of gene expression time courses in response to a large variety of internal and environmental perturbations. In ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 3, pp. 233-245, 2010]]>A new n log n algorithm for the scheduling problem of n independent jobs on m identical parallel machines with minimum makespan objective is proposed and its worst-case performance ratio is estimated. The algorithm iteratively combines partial solutions that are obtained by partitioning the set of jobs into suitable families of subsets. The computational behavior on three families of ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 1, pp. 39-51, 2010]]>Most of the well known methods for solving multi-objective combinatorial optimization problems deal with only two objectives. In this paper, we develop a metaheuristic method for solving multi-objective assignment problems with three or more objectives. This method is based on the dominance cost variant of the multi-objective simulated annealing (DCMOSA) and hybridizes neighborhood search techniques which consist ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 2, pp. 149-164, 2010]]>Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 3, pp. 209-211, 2010]]>

In this paper, both stochastic local search (SLS) and tabu search (TS) are studied for the optimal winner determination problem (WDP) in combinatorial auctions. The proposed methods are evaluated on various benchmark problems, and compared with the hybrid simulated annealing (SAGII), the memetic algorithms (MA) and Casanova. The computational experiments show that the SLS provides competitive results and finds solutions ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 2, pp. 165-180, 2010]]>The combined analysis of tissue micro array and drug response datasets has the potential of revealing valuable knowledge about various relations among gene expressions and drug activity patterns in tumor cells. However, the amount and the complexity of biological data needs appropriate data mining models in order to extract interesting patterns and useful information. The ultimate goal of this paper ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 3, pp. 275-289, 2010]]>A line is sought in the plane which minimizes the sum of the k largest (Euclidean) weighted distances from n given points. This problem generalizes the known straight-line center and median problems and, as far as the authors are aware, has not been tackled up to now. By way of geometric duality it is shown that such a line ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 1, pp. 1-17, 2010]]>A dual ascent reoptimization technique is proposed for updating optimal flows for the minimum cost network flow problem (MCNFP) given any number of simultaneous, heterogeneous changes to the network attributes (i.e. supply at nodes, arc costs and arc capacities) and the optimal solutions to the prior primal and dual problems. Significant savings in computation time can be achieved through ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 4, pp. 291-309, 2010]]>In this article, the impact of single-objective methods as intensification factors in a multi-objective approach is presented for the flexible docking problem. Based on a novel tri-objective model, a parallel multi-objective genetic algorithm has been designed. However, due to the high variability of the energy objective, intensification methods focused on this objective have been also included ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 2, pp. 195-208, 2010]]>The growing quality and delay requirements have catalyzed the emergence of new commercial paradigms, which have strongly modified the customer–supplier relationship. Customers and suppliers become more and more linked with contracts or global orders spanned over a relatively important period. This paper, examines a type of contract which specifies a fixed and cyclic delivery dates with delivery quantities varying ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 4, pp. 311-342, 2010]]>Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 2, pp. 129-130, 2010]]>

An original algorithm is presented that generates both restricted integer compositions and restricted integer partitions that can be constrained simultaneously by (a) upper and lower bounds on the number of summands (“parts”) allowed, and (b) upper and lower bounds on the values of those parts. The algorithm can implement each constraint individually, or no constraints to generate unrestricted sets of ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 9, no. 1, pp. 53-97, 2010]]>Recently, we have proposed a Multi-Objective Bayesian Artificial Immune System (MOBAIS) to deal effectively with building blocks (high-quality partial solutions coded in the solution vector) in combinatorial multi-objective problems. By replacing the mutation and cloning operators with a probabilistic model, more specifically a Bayesian network representing the joint distribution of promising solutions, MOBAIS takes into account the ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 2, pp. 151-173, 2009]]>The biclustering technique was developed to avoid some of the drawbacks presented by standard clustering techniques, such as their impossibility of finding correlating data under a subset of features, and, consequently, to allow the extraction of more accurate information from datasets. Given that biclustering requires the optimization of at least two conflicting objectives (residue and volume) and that multiple independent ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 2, pp. 175-202, 2009]]>Much of contemporary research in Artificial Immune Systems (AIS) has partitioned into either algorithmic machine learning and optimisation, or, modelling biologically plausible dynamical systems, with little overlap between. We propose that this dichotomy is somewhat to blame for the lack of significant advancement of the field in either direction and demonstrate how a simplistic interpretation of Perelson’s shape-space formalism ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 2, pp. 125-149, 2009]]>In this paper, we consider power control for the uplink of a direct-sequence code-division multiple-access data network. In the uplink, the purpose of power control is for each user to transmit enough power so that it can achieve the required quality of service without causing unnecessary interference to other users in the system. One method that has ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 1, pp. 1-18, 2009]]>Previous work suggests that innate immunity and representations of tissue can be useful when combined with artificial immune systems. Here we provide a new implementation of tissue for artificial immune systems using systemic computation, a new model of computation and corresponding computer architecture based on a systemics world-view and supplemented by the incorporation of natural characteristics. We show using ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 2, pp. 203-225, 2009]]>The paper considers the hybrid flow-shop scheduling problem with multiprocessor tasks. Motivated by the computational complexity of the problem, we propose a memetic algorithm for this problem in the paper. We first describe the implementation details of a genetic algorithm, which is used in the memetic algorithm. We then propose a constraint programming based branch-and-bound algorithm to ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 3, pp. 271-292, 2009]]>In this paper, we investigate how robust and flexible solutions of a number of stochastic variants of the capacitated vehicle routing problem can be obtained. To this end, we develop and discuss a method that combines a sampling based approach to estimate the robustness or flexibility of a solution with a metaheuristic optimization technique. This combination allows us to solve ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 4, pp. 387-407, 2009]]>This paper addresses the classification task of data mining (a form of supervised learning) in the context of an important bioinformatics problem, namely the prediction of protein functions. This problem is cast as a hierarchical classification problem. The protein functions to be predicted correspond to classes that are arranged in a hierarchical structure (this takes the form of a class ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 2, pp. 103-123, 2009]]>In the last 25 years a significant number of papers have treated the interesting case of the location of facilities which do not generate and/or attract flow, but intercept it. These facilities can be used by the flow units of the network or proposed to/imposed on them along their pre-planned path from an origin to a destination. In ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 1, pp. 35-79, 2009]]>Large neighborhood search (LNS) is a combination of constraint programming (CP) and local search (LS) that has proved to be a very effective tool for solving complex optimization problems. However, the practice of applying LNS to real world problems remains an art which requires a great deal of expertise. In this paper, we show how adaptive techniques can be used ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 3, pp. 245-270, 2009]]>We describe an algorithm for the construction of discretized Voronoi diagrams on a CPU within the context of a large scale numerical fluid simulation. The Discrete Voronoi Chain (DVC) algorithm is fast, flexible and robust. The algorithm stores the Voronoi diagram on a grid or lattice that may be structured or unstructured. The Voronoi diagram is computed by alternatively updating ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 3, pp. 343-355, 2009]]>The method of choosing the best boundaries that make strata internally homogeneous, given some sample allocation, is known as optimum stratification. In order to make the strata internally homogeneous, the strata are constructed in such a way that the strata variances should be as small as possible for the characteristic under study. In this paper the problem of determining optimum ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 4, pp. 409-423, 2009]]>We present a novel approach for compressing relatively small unordered data sets by means of combinatorial optimization. The application background comes from the field of biometrics, where the embedding of fingerprint template data into images by means of watermarking techniques requires extraordinary compression techniques. The approach is based on the construction of a directed tree, covering a sufficient subset of ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 3, pp. 293-334, 2009]]>Solving systems of nonlinear equations is perhaps one of the most difficult problems in all numerical computation. Although numerous methods have been developed to attack this class of numerical problems, one of the simplest and oldest methods, Newton’s method is arguably the most commonly used. As is well known, the convergence and performance characteristics of Newton’s method can be highly ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 4, pp. 425-443, 2009]]>This paper describes progress on the TLM modelling of the Laplace equation, in particular, how the rate of convergence is influenced by the choice of scattering parameter for a particular discretisation. The hypothesis that optimum convergence is achieved when the real and imaginary parts for the lowest harmonic in a Fourier solution cancel appears to be upheld. The Fourier solution ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 4, pp. 363-385, 2009]]>We point out that the total number of trails and the total number of paths of given length, between two vertices of a simple undirected graph, are obtained as expectation values of specifically engineered quantum mechanical observables. Such observables are contextual with some background independent theories of gravity and emergent geometry. Thus, we point out yet another situation in which ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 3, pp. 335-342, 2009]]>This research presents the implementation of GSCF, an AIS-based control framework, on a distributed wireless sensor network for tracking search and rescue robots in open fields. The General Suppression Control Framework (GSCF) is a framework inspired by the suppression hypothesis of the immune discrimination theory. The framework consists of five distinct components; each carries a specific function that can ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 2, pp. 227-242, 2009]]>Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 2, pp. 101-102, 2009]]>

This paper presents a chance constrained programming approach to the problem of maximizing the ratio of two linear functions of decision variables which are subject to linear inequality constraints. The coefficient parameters of the numerator of the objective function are assumed to be random variables with a known multivariate normal probability distribution. A deterministic equivalent of the stochastic linear fractional ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 4, pp. 357-361, 2009]]>Determining of a maximal network flow is a classic problem in discrete optimization with many applications. In this paper, a new algorithm based on the Dinic’s method is presented. Algorithms of the Dinic’s method work evidently faster than theoretical bounds for a randomized network. This paper presents a parameterized and easy to implement family of algorithms of finding a saturating ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 1, pp. 19-34, 2009]]>We consider routing in symmetrical three stage Clos networks. Especially we search for the routing of an additional connection that requires the least rearrangements, i.e. the minimal number of changes of already routed connections. We describe polynomial methods, based on matchings and edge colorings. The basic idea is to swap colors along alternating paths. The paths need to be ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 8, no. 1, pp. 81-100, 2009]]>Computational grids are an important emerging paradigm for large-scale distributed computing. As grid systems become more wide-spread, techniques for efficiently exploiting the large amount of grid computing resources become increasingly indispensable. A key aspect in order to benefit from these resources is the scheduling of jobs to grid resources. Due to the complex nature of grid systems, the ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 2, pp. 217-236, 2008]]>This paper introduces a new hybrid algorithmic nature inspired approach based on particle swarm optimization, for solving successfully one of the most popular logistics management problems, the location routing problem (LRP). The proposed algorithm for the solution of the location routing problem, the hybrid particle swarm optimization (HybPSO-LRP), combines a particle swarm optimization (PSO) algorithm, the multiple phase neighborhood ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 1, pp. 59-78, 2008]]>In previous work (Krasnogor, http://www.cs.nott.ac.uk/~nxk/papers.html. In: Studies on the Theory and Design Space of Memetic Algorithms. Ph.D. thesis, University of the West of England, Bristol, UK, 2002; Krasnogor and Smith, IEEE Trans Evol Algorithms 9(6):474–488, 2005) we develop a syntax-only classification of evolutionary algorithms, in particular so-...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 1, pp. 3-24, 2008]]>The generation of efficient Gray codes and combinatorial algorithms that list all the members of a combinatorial object has received a lot of attention in the last few years. Knuth gave a code for the set of all partitions of [n] = {1,2,...,n}. Ruskey presented a modified version of Knuth’s algorithm with distance 2. Ehrlich introduced a ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 3, pp. 291-310, 2008]]>We introduce and test a new approach for the bi-objective routing problem known as the traveling salesman problem with profits. This problem deals with the optimization of two conflicting objectives: the minimization of the tour length and the maximization of the collected profits. This problem has been studied in the form of a single objective problem, where either the ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 2, pp. 177-195, 2008]]>DNA codes are sets of words of fixed length n over the alphabet {A,C,G,T} which satisfy a number of combinatorial conditions. They have application in DNA computing, in DNA microarray technologies and as molecular bar codes. The combinatorial conditions considered are (i) minimum Hamming distance d, (ii) fixed GC content and, in some cases (iii) minimum distance ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 3, pp. 311-326, 2008]]>This paper tackles the Cyclic Hoists Scheduling Problem. This problem is often encountered in electroplating facilities when mass production is required. Then a repetitive sequence of moves is searched for the hoists. We more precisely deal with a global optimization problem that simultaneously considers the design and the scheduling of such production lines. It consists in studying systems integrating several ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 2, pp. 197-215, 2008]]>Applying numerical optimisation methods in the field of aerodynamic design optimisation normally leads to a huge amount of heterogeneous design data. While most often only the most promising results are investigated and used to drive further optimisations, general methods for investigating the entire design dataset are rare. We propose methods that allow the extraction of comprehensible knowledge from aerodynamic design ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 4, pp. 329-350, 2008]]>A self-organized scheme for the allocation service tasks in adaptive or organic computing systems is proposed. Such computing systems are highly self-organized and the components ideally adapt to the needs of users or the environment. Typically, the components of such systems need some service from time to time in order perform their work efficiently. Since the type of ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 2, pp. 237-254, 2008]]>In the paper, we use a mathematical model to study the population dyna mics of replicating malaria parasites and their interaction with the immune cells within a human host. The model is formulated as a system of age-structured partial differential equations that are then integrated over age to obtain a system of nonlinear delay differential equations. Our model incorporates ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 1, pp. 79-97, 2008]]>The evolutionary metaheuristic called scatter search has been applied successfully to optimization problems for several years. In this paper, we apply the scatter search technique to the well-known 0–1 multidimensional knapsack problem. We propose a new relaxation-based diversification generator, which produces an initial population with elite solutions. The computational results obtained for a set of classic and ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 2, pp. 143-159, 2008]]>In many classification applications and face recognition tasks, there exist unlabelled data available for training along with labelled samples. The use of unlabelled data can improve the performance of a classifier. In this paper, a semi-supervised growing neural gas is proposed for learning with such partly labelled datasets in face recognition applications. The classifier is first trained on the ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 4, pp. 425-435, 2008]]>The graph b-coloring is an interesting technique that can be applied to various domains. The proper b-coloring problem is the assignment of colors (classes) to the vertices of one graph so that no two adjacent vertices have the same color, and for each color class there exists at least one dominating vertex which is adjacent (dissimilar) to all ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 4, pp. 389-423, 2008]]>In this paper, both scatter search (SS) and genetic algorithms (GAs) are studied for the NP-Hard optimization variant of the satisfiability problem, namely MAX-SAT. First, we investigate a new selection strategy based on both fitness and diversity to choose individuals to participate in the reproduction phase of a genetic algorithm. The resulting algorithm is enhanced in two ways ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 2, pp. 101-124, 2008]]>The Real Time Vehicle Routing Problem RTVRP is a dynamic routing problem where requests are generated dynamically during the operation horizon without any previous knowledge. Received requests need to be answered as fast as possible and then assigned to a vehicle to be served. Due to timing constraints of the RTVRP, a solving approach should give the best compromise between ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 2, pp. 161-176, 2008]]>Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 4, pp. 327-328, 2008]]>

This paper introduces a new paradigm in the design of sorting algorithms, viz., fault tolerance. Fault tolerance is an important concept in modern day computing and design workflows must accommodate this need. In general, there are a number of avenues for faults to occur and techniques to address the same; this paper focusses on only one source of faulty behavior, ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 3, pp. 255-276, 2008]]>The capacitated p-median problem (CPMP) consists of finding p nodes (the median nodes) minimizing the total distance to the other nodes of the graph, with the constraint that the total demand of the nodes assigned to each median does not exceed its given capacity. In this paper we propose a cutting plane algorithm, based on Fenchel cuts, which allows ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 1, pp. 43-58, 2008]]>As was mentioned above the problem is a simplification of real problems appearing in the management of Earth observation satellites. In particular, we consider just a single revolution of the satellite. Below, we define it briefly. Given: • a number Nr of requests for satellite pictures that may be satisfied fully or partially (a request defines an area to be ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 1, pp. 25-42, 2008]]>In practical data mining tasks, high-dimensional data has to be analyzed. In most of the cases it is very informative to map and visual- ize the hidden structure of a complex data set in a low-dimensional space. In this paper a new class of mapping algorithms is deflned. These algo- rithms combine topology representing networks and difierent nonlinear ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 4, pp. 351-370, 2008]]>In this paper, a cooperative search method, based on a multi-agent structure is developed to deal with the k-coloring problem. Three agents coordinate using an adaptive memory, a search agent, an intensification agent and a diversification agent. We use the results of a preliminary fitness landscape study to adjust the navigation strategy in the solution space and to ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 2, pp. 125-142, 2008]]>We develop an integrated dynamic programming—linear programming (LP) model to solve for optimal land exploitation for a given crop. The model applies deficit irrigation in order to increase the irrigated area at the expense of reducing the crop yield per unit area. The dynamic program guarantees that deficit irrigation is considered only when it is economically efficient. Moreover, it ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 3, pp. 277-289, 2008]]>General finite mixture models are powerful tools for the density-based grouping of multivariate i.i.d. data, but they lack data visualization capabilities, which reduces their practical applicability to real-world problems. Generative topographic mapping (GTM) was originally formulated as a constrained mixture of distributions in order to provide simultaneous visualization and clustering of multivariate data. In its inception, ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 4, pp. 371-387, 2008]]>Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, 2008]]>

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 7, no. 2, pp. 99-100, 2008]]>

The main objective of this paper consists in modelling, optimizing, and controlling container transfer operations inside intermodal terminals. More specifically, maritime container terminals are here considered, involving three kinds of transportation modes, i.e., maritime, rail, and road transport. Generally speaking, an intermodal port terminal can be seen as a system of container flows with two interfaces, towards the hinterland ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 1, pp. 109-133, 2007]]>A Genetic Programming based approach for solving classification problems is presented in this paper. Classification is understood as the act of placing an object into a set of categories, based on the object’s properties; classification algorithms are designed to learn a function which maps a vector of object features into one of several classes. This is done by analyzing a ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 3, pp. 455-480, 2007]]>During ice storms, ice forms on high voltage electrical lines. This ice formation often results in downed lines and has been responsible for considerable damage to life and property as was evidenced in the catastrophic ice storm of Quebec recently. There are two main aspects, viz., the formation of ice and its timely mitigation. In this paper, we mathematically model ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 2, pp. 273-286, 2007]]>A variant of the classical vehicle routing problem, where vehicles can be assigned to more than one route within a working time period, is investigated. A hybrid Genetic Algorithm, which uses a new non-binary chromosome representation and which is enhanced by a domain specific data structure, appropriate genetic operators and a scheme for chromosome evaluation, is proposed. Test problems ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 4, pp. 591-613, 2007]]>One of the basic operations in communication networks consists in establishing routes for connection requests between physically separated network nodes. In many situations, either due to technical constraints or to quality-of-service and survivability requirements, it is required that no two routes interfere with each other. These requirements apply in particular to routing and admission control in large-scale, ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 3, pp. 361-391, 2007]]>Real optimization problems often involve not one, but multiple objectives, usually in conflict. In single-objective optimization there exists a global optimum, while in the multi-objective case no optimal solution is clearly defined but rather a set of solutions, called the Pareto-optimal front. Thus, the goal of multi-objective strategies is to generate a set of non-dominated ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 2, pp. 213-230, 2007]]>The paper presents an approach based on the principles of immune systems applied to the anomaly detection problem. Flexibility and efficiency of the anomaly detection system are achieved by building a model of the network behavior based on the self-nonself space paradigm. Covering both self and nonself spaces by hyperrec- tangular structures is proposed. The structures corresponding to self-...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 3, pp. 411-431, 2007]]>This work presented a new approach to solve the location management problem by using the location areas approach. A combination of Genetic Algorithm and Hopfield Neural Network is used to find the optimal configuration of location areas in a mobile network. Toward this end, the location areas configuration of the network is modeled so that the general condition of all ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 3, pp. 481-507, 2007]]>In this paper we consider integrated planning of transportation of raw material, production and distribution of products of the supply chain at Södra Cell AB, a major European pulp mill company. The strategic planning period is one year. Decisions included in the planning are transportation of raw materials from harvest areas to pulp mills, production mix and contents at pulp ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 1, pp. 25-45, 2007]]>We consider a single-period multi-location inventory system where inventory choices at each location are centrally coordinated. Transshipments are allowed as recourse actions in order to reduce the cost of shortage or surplus inventory after demands are realized. This problem has not been solved to optimality before for more than two locations with general cost parameters. In this paper ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 1, pp. 47-75, 2007]]>We consider a version of the total flow time single machine scheduling problem where uncertainty about processing times is taken into account. Namely an interval of equally possible processing times is considered for each job, and optimization is carried out according to a robustness criterion. We propose the first mixed integer linear programming formulation for the resulting optimization problem and ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 2, pp. 287-296, 2007]]>Received: date / Accepted: date Abstract Assigning and scheduling vehicle routes in a dynamic environ- ment is a crucial management problem. Despite numerous publications deal- ing with e-cient scheduling methods for vehicle routing, very few addressed the inherent stochastic and dynamic nature of travel times. In this paper, a vehicle routing problem with time-dependent travel times due to poten- ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 1, pp. 151-173, 2007]]>Road blocking due to thawing or heavy rains annually contribute to a considerable loss in Swedish forestry. Companies are forced to build up large stocks of raw material (saw and pulp logs) in order to secure a continuous supply when access to the road network is uncertain. Storage outdoors leads to quality deterioration and monetary losses. Other related costs due ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 1, pp. 3-23, 2007]]>This paper presents a model for evaluation of transport policies in multimodal networks with road and parking capacity constraints. The proposed model simultaneously considers choices of travelers on route, parking location and mode between auto and transit. In the proposed model, it is assumed that auto drivers make a simultaneous route and parking location choice in a user equilibrium manner, ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 2, pp. 239-257, 2007]]>An interval-parameter fuzzy linear programming method (IFMOLP) is proposed in this study for multiple objective decision-making under uncertainty. As a hybrid of interval-parameter and fuzzy methodologies, the IFMOLP incorporates interval-parameter linear programming and fuzzy multiobjective programming approaches to form an integrated optimization system. The method inherits advantages of interval-parameter programming, and allows uncertainties and decision-...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 2, pp. 195-212, 2007]]>This paper introduces a simple heuristic for a quadratic programming sub-problem within a Lagrangean relaxation heuristic for a dynamic pricing and lot-size problem. This simple heuristic is demonstrated to work well on both ‘standard problem instances’ from the CLSP-literature, as well as on very large-scale cases. Additionally, we introduce price constraints within the framework of dynamic ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 1, pp. 135-149, 2007]]>In this paper we consider a common optimization problem faced by a printing company while designing masters for advertisement material. A printing company may receive from various customers, advertisements for their products and services and their demand is for a specified number of copies to be printed. In a particular case, the printer receives these orders to be delivered next ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 2, pp. 259-271, 2007]]>We study a vehicle routing problem in which vehicles are dispatched multiple times a day for product delivery. In this problem, some customer orders are known in advance while others are uncertain but are progressively realized during the day. The key decisions include determining which known orders should be delivered in the first dispatch and which should be delivered in ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 1, pp. 87-107, 2007]]>In this work, we consider the identification problem of the diffusion coef-ficient in two-dimensional elliptic equations. For parameterization, we use the zonation method: the diffusion coefficient is assumed to be a piecewise constant space function and unknowns are both the diffusion coefficient values and the geometry of the zones. An algorithm based on geometric principles is developed in ...

Journal: Journal of Mathematical Modelling and Algorithms - JMMA, vol. 6, no. 4, pp. 529-545, 2007]]>