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This paper presents a large neighbourhood search for solving the planar location-allocation problem. This location-allocation problem entails to find the location of specified number of facilities on a plane and their customer allocations on a plane. It is generally assumed that all facilities have the same given capacity. A greedy algorithm is used to generate initial solutions and then an exchange neighbourhood procedure is put forward to explore large neighbourhood heuristically. The experiments are conducted to assess the performance of the proposed method using benchmark data sets taken from the facility location literature. The preliminary computational results show that the proposed methods provide competitive results when compared to the best known results from the literature. Some future research investigations on this capacitated planar location problem are also briefly highlighted.

The Container Loading Problem (CLP) is a study of loading a subset of goods or parcels of different sizes into a three-dimensional rectangular container of fixed dimensions such that the volume of packed boxes is maximized. In this paper, an improved version of the modified George and Robinson heuristic (iGRMOD) is developed to solve the CLP. Comparison computational results on benchmark data set from the literature will be presented. The performances of the iGRMOD are superior than the GRMOD and other heuristics reported in the literature.

To improve space utilization, the method for handling spaces plays an important role in the container loading problem. This paper deals with loading a set of cuboid items into a single container to maximize the utilization of the space. Six space partitions are presented and a set of rules for merging spaces is proposed. Through experimentation, using a benchmark data set, the influence of partitioning and merging are analyzed. The experimental results show that partitioning and merging in which all loaded boxes have one hundred percent support from below can produce good space utilization.

The need to accurately model multiscale phenomena is ubiquitous in eddy-current nondestructive evaluation. By using volume-integral equations, we are able to develop a very simple algorithm for accurately computing the response of a very small anomaly in the presence of a much larger one. We validate the algorithm and its associated code in VIC-3D{copyright, serif} through benchmark data on two test sets: (1) a notch at a bolt hole with an upper surface coil, and (2) a notch in a bolt hole with a plate surface coil.

The mixed vehicle routing problem with backhauls is investigated using an ant system heuristic. This distribution problem seems to suffer from a lack of published work even though it has immense practical applicability especially within logistic systems. Some enhancements to the basic ant system algorithm are embedded into the search. In particular a focus is on the choice in the placement of ants, the use of a site‐dependent candidate list, the introduction of a look ahead‐based visibility, and appropriate strategies for updating local and global trails. Encouraging computational results are reported when tested on benchmark data sets.

This paper discusses the critical experiments planned in the U.S. for the Topaz‐II reactor program. The experiments for each phase of the project are discussed. The initial experiments will focus on obtaining benchmark data on the Topaz‐II flight configuration for validation of computer codes. The final experiments will be conducted to perform necessary pre‐flight measurements and settings. The critical experiments are part of an integrated program to maximize flight safety and system reliability.