This paper addresses the open vehicle routing problem with time window(OVRPTW), where each vehicle does not need to return to the depot after completing the delivery task.The optimization objective is to minimize the ...This paper addresses the open vehicle routing problem with time window(OVRPTW), where each vehicle does not need to return to the depot after completing the delivery task.The optimization objective is to minimize the total distance. This problem exists widely in real-life logistics distribution process.We propose a hybrid column generation algorithm(HCGA) for the OVRPTW, embedding both exact algorithm and metaheuristic. In HCGA, a label setting algorithm and an intelligent algorithm are designed to select columns from small and large subproblems, respectively. Moreover, a branch strategy is devised to generate the final feasible solution for the OVRPTW. The computational results show that the proposed algorithm has faster speed and can obtain the approximate optimal solution of the problem with 100 customers in a reasonable time.展开更多
利用隔壁精馏塔替代混合碳五馏分原有分离流程中的脱丁烷塔和碳五预分离塔,通过Aspen Plus V12软件对混合碳五馏分的提纯流程进行稳态模拟,在此基础上运用灵敏度分析工具,对隔壁精馏塔的操作参数进行优化。结果表明:采用隔壁精馏塔替代...利用隔壁精馏塔替代混合碳五馏分原有分离流程中的脱丁烷塔和碳五预分离塔,通过Aspen Plus V12软件对混合碳五馏分的提纯流程进行稳态模拟,在此基础上运用灵敏度分析工具,对隔壁精馏塔的操作参数进行优化。结果表明:采用隔壁精馏塔替代脱丁烷塔和碳五预分离塔,最佳原料进料位置为第11块塔板、最佳质量回流比为5、最佳侧线采出位置为第7块塔板、最佳侧线采出量为500 kg h,气相回流位置为第37块塔板,液相回流位置为第12块塔板;在相同进料条件和相同碳五馏分纯度的前提下,与采用常规精馏工艺相比,采用隔壁塔精馏工艺时冷却能耗降低17.04%,加热能耗降低16.69%。展开更多
基金supported by the National Natural Science Foundation of China (61963022,51665025,61873328)。
文摘This paper addresses the open vehicle routing problem with time window(OVRPTW), where each vehicle does not need to return to the depot after completing the delivery task.The optimization objective is to minimize the total distance. This problem exists widely in real-life logistics distribution process.We propose a hybrid column generation algorithm(HCGA) for the OVRPTW, embedding both exact algorithm and metaheuristic. In HCGA, a label setting algorithm and an intelligent algorithm are designed to select columns from small and large subproblems, respectively. Moreover, a branch strategy is devised to generate the final feasible solution for the OVRPTW. The computational results show that the proposed algorithm has faster speed and can obtain the approximate optimal solution of the problem with 100 customers in a reasonable time.
文摘利用隔壁精馏塔替代混合碳五馏分原有分离流程中的脱丁烷塔和碳五预分离塔,通过Aspen Plus V12软件对混合碳五馏分的提纯流程进行稳态模拟,在此基础上运用灵敏度分析工具,对隔壁精馏塔的操作参数进行优化。结果表明:采用隔壁精馏塔替代脱丁烷塔和碳五预分离塔,最佳原料进料位置为第11块塔板、最佳质量回流比为5、最佳侧线采出位置为第7块塔板、最佳侧线采出量为500 kg h,气相回流位置为第37块塔板,液相回流位置为第12块塔板;在相同进料条件和相同碳五馏分纯度的前提下,与采用常规精馏工艺相比,采用隔壁塔精馏工艺时冷却能耗降低17.04%,加热能耗降低16.69%。
