The traveling salesman problem (TSP) is one of the most important combinational optimization problems that have nowadays received much attention because of its practical applications in industrial and service problems. In this paper, a hybrid two-phase meta-heuristic algorithm called MACSGA used for solving the TSP is presented. At the first stage, the TSP is solved by the modified ant colony s...

We propose a heuristic global optimization technique which combines combinatorial and continuous local search. The combinatorial component, based on Reactive Search Optimization, generates a trajectory of binary strings describing search districts. Each district is evaluated by random sampling and by selective runs of continuous local search. A reactive prohibition mechanisms guarantees that th...

Many methods have been developed for structural size and configuration optimization in which cross-sectional areas are usually assumed to be continuous. In most practical structural engineering design problems, however, the design variables are discrete. This paper proposes two efficient structural optimization methods based on the harmony search (HS) heuristic algorithm that treat both discret...

The order in which nodes are explored in a (depth-first) iterative deepening search strategy is principally determined by the condition under which a path of the search tree is cut off in each search phase. A corresponding criterion, which has a strong influence on the performance of the overall (heuristic) search procedure, is generally realized in the form of an upper cost bound. In this pape...

The effects of combining search and modelling techniques can be complex and unpredictable, so guidelines are very important for the design and development of effective and robust solvers and models. A recently observed phenomenon is the negative effect of symmetry breaking constraints on local search performance. The reasons for this are poorly understood, and we attempt to shed light on the ph...

Many instances of NP-hard problems can be solved efficiently if the treewidth of their corresponding graph is small. Finding the optimal tree decompositions is an NP-hard problem and different algorithms have been proposed in the literature for generation of tree decompositions of small width. In this paper is presented new iterated local search algorithm to find good upper bounds for treewidth...

This paper presents several local search heuristics for the problem of scheduling a single machine to minimize total weighted tardiness. We introduce a new binary encoding scheme to represent solutions, together with a heuristic to decode the binary representations into actual sequences. This binary encoding scheme is compared to the usual 'natural' permutation representation for descent, simul...

• Minimizing the aggregated fuel consumption on an inland waterway network. Mathematical programming formulation of speed optimization problem. Local search-based heuristic that allows scalability towards realistic input instances. Computational experiments conducted using real AIS data. Fuel and CO 2 emission are among main criteria to assess environmental economical impact vessels waterways. ...

The Heterogeneous Fleet Vehicle Routing Problem (HFVRP) is an important variant of the classical Capacitated (CVRP) that aims to find routes minimize total traveling cost a heterogeneous fleet vehicles. This problem great interest given its importance in many industrial and commercial applications. In this paper, we present Adaptive Iterated Local Search (AILS) heuristic for HFVRP. AILS local s...

barrel vaults are attractive space structures that cover large area without intermediate supports. in this paper, the charged search system (css) optimization algorithm is employed for optimal design of barrel vaults. this method utilizes the governing laws of coulomb and gauss from electrostatics and the newtonian law of mechanics. the results demonstrate the efficiency of the discrete css alg...