In this paper, we develop a new heuristic procedure for the linear ordering problem (LOP). This NP-hard problem has a significant number of applications in practice. The LOP, for example, is equivalent to the so-called triangulation problem for input-output tables in economics. In this paper we concentrate on matrices that arise in the context of this real-world application. The proposed algori...

Singapore Management University, 469 Buki t T imah Road Singapore 259756 [email protected] Fei X iao School of Comput ing National University of Singapore 3 Science Drive 2 Singapore 117543 [email protected] We propose a Node Centroid method with Hil lClimbing to solve the well-known matrix bandwidth minimization problem, which is to permute rows and columns of the matrix to minimize its band...

Process checkpoint/restart is a very useful technology for process migration, load balancing, crash recovery, rollback transaction, job controlling and many other purposes. Although process migration has not yet been widely used and is not widely available commercial systems, the growing shift of computing facilities from supercomputers to networked workstations and distributed systems is incre...

The free clustered travelling salesman problem (FCTSP) is an extension of the classical travelling salesman problem where the set of vertices is partitioned into clusters, and the task is to find a minimum cost Hamiltonian tour such that the vertices in any cluster are visited contiguously. This paper proposes the use of a memetic algorithm (MA) that combines the global search ability of Geneti...

This work addresses the Vehicle Routing Problem with Simultaneous Pickup and Delivery (VRPSPD). Due to its complexity, we propose a heuristic algorithm for solving it, so-called GENVNS-TS-CL-PR. This algorithm combines the heuristic procedures Cheapest Insertion, Cheapest Insertion with multiple routes, GENIUS, Variable Neighborhood Search (VNS), Variable Neighborhood Descent (VND), Tabu Search...

In this work we deal with sandwich graphs G = (V,E) and present the notion of vertices f -controlled by a subset M ⊆ V . We introduce the generalized maxcontrolled set problem (gmcsp), where gaps and positive weights are associated to each vertex of V . In this case, the objective is find a sandwich graph G in order to maximize the sum of the weights associated to all vertices f -controlled by ...

Given a set of nodes and the distances between them, the traveling salesman problem (TSP) consists in finding the shortest route that visits each node exactly once and returns to the first. The Steiner traveling salesman problem (STSP) is a variant of the TSP that assumes that only a given subset of nodes must be visited by a shortest route, eventually visiting some nodes and edges more than on...

The cutwidth minimization problem consists of finding a linear layout of a graph so that the maximum linear cut of edges is minimized. This NP-hard problem has applications in network scheduling, automatic graph drawing and information retrieval. We propose a heuristic method based on the Scatter Search (SS) methodology for finding approximate solutions to this optimization problem. This metahe...

Given an undirected graph with edge weights, the MAX-CUT problem consists in finding a partition of the nodes into two subsets, such that the sum of the weights of the edges having endpoints in different subsets is maximized. It is a well-known NP-hard problem with applications in several fields, including VLSI design and statistical physics. In this paper, a greedy randomized adaptive search p...

Distributed object computing forms the basis for nextgeneration application middleware. At the heart of distributed object computing are Object Request Brokers (ORBs), which automate many tedious and error-prone distributed programming tasks. Like many other distributed applications, conventional ORBs use statically configured software designs, which are hard to maintain, port, and optimize. Li...