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This paper considers a problem of uniform-machine scheduling with machine release times to minimize makespan. Firstly, four properties of swapping jobs are proposed. Then, based on the properties, a heuristic algorithm is presented, which takes the LPT schedule as its initial solution and improves the solution by repeatedly swapping the jobs between two machines with the maximal and minimal makespan. Finally, computational results show that the presented heuristic is efficient and effective. [ABSTRACT FROM AUTHOR]

Vehicle routing problem (VRP) plays a vital role in logistics research. The multi-depot vehicle routing problem with time windows (MDVRPTW), an extension of VRP with time windows (VRPTW), is very complicated to be solved. This paper presented a two-stage heuristic to solve MDVRPTW. In the two-stage heuristic, aggregation-based clustering algorithm was firstly proposed to transfer MDVRPTW to several VRPTWs, and ant colony optimization (ACO) was developed to optimize each VRPTW. Two improvement strategies: crossover operation and adaptive ant-weight strategy, are designed to improve ACO. The performance of the two-stage heuristic was examined by use of some classic instances. Results show that the two-stage heuristic is a powerful tool for MDVRPTW. [ABSTRACT FROM AUTHOR]

This paper deals with the human resource scheduling problem of multiple IT projects. According to its specific requirements on time and personnel, the duration of the whole development process can be divided into equal-length time slices. Based on the relations among activities and personnel in a certain time slice, the search tree of personnel scheduling solutions can be constructed. By connecting all the search trees sequentially from all the time slices, the solution tree for the whole problem can be generated and all the solutions can be listed. Then, based on the average of advanced completion rate and the variance of advanced completion rate, the optimal solution can be found. By adding heuristic rules to this algorithm, the searching space can contract rapidly, and the searching efficiency can be enhanced greatly. In view of the particularities of this algorithm, it can be applied to many generalized resource scheduling problems that possess similar conditions with the problem described above. After applying this algorithm to a mock example, some regular patterns emerged, showing the potential that further heuristic rules can be extracted. [ABSTRACT FROM AUTHOR]