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This paper studies the multi-depot open vehicle routing problem (MDOVRP), a variant of the vehicle routing problem (VRP), in which vehicles start from several depots and are not required to return to the depot. Despite the vast amount of literature about VRPs, the MDOVRP has received very little attention from researchers. In this paper, a new hybrid genetic algorithm is presented for finding the routes that minimize the traveling cost of the vehicles. Computational results on a number of test instances indicate the proposed algorithm dominates the CPLEX solver and the existing approach in the literature. Meanwhile, experiments are conducted on multi-depot VRP benchmarks, and the results are compared with a sophisticated tabu search approach and an exact method. 相似文献
994.
某压缩机转轴在正常工作中突然发生断裂,通过对失效转轴的化学成分、力学性能、显微组织、裂纹及断口形貌进行分析和检验,查明了其断裂原因。结果表明:该转轴断裂为旋转弯曲疲劳断裂;断裂起源于转轴补焊热影响区的沿晶微裂纹,转轴加工过程中表面进行补焊并且补焊工艺控制不当是导致其断裂失效的主要原因。 相似文献
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Understanding the Charge‐Transfer State and Singlet Exciton Emission from Solution‐Processed Small‐Molecule Organic Solar Cells
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998.
Kvar C. L. Black Tadas S. Sileika Ji Yi Ran Zhang José G. Rivera Phillip B. Messersmith 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(1):169-178
Illumination of noble metal nanoparticles at the plasmon resonance causes substantial heat generation, and the transient and highly localized temperature increases that result from this energy conversion can be exploited for photothermal therapy by plasmonically heating gold nanorods (NRs) bound to cell surfaces. Here, plasmonic heating is used for the first time to locally release silver from gold core/silver shell (Au@Ag) NRs targeted to bacterial cell walls. A novel biomimetic method of preparing Au@Ag core–shell NRs is employed, involving deposition of a thin organic polydopamine (PD) primer onto Au NR surfaces, followed by spontaneous electroless silver metallization, and conjugation of antibacterial antibodies and passivating polymers for targeting to gram‐negative and gram‐positive bacteria. Dramatic cytotoxicity of S. epidermidis and E. coli cells targeted with Au@Ag NRs is observed upon exposure to light as a result of the combined antibacterial effects of plasmonic heating and silver release. The antibacterial effect is much greater than with either plasmonic heating or silver alone, implying a strong therapeutic synergy between cell‐targeted plasmonic heating and the associated silver release upon irradiation. The findings suggest a potential antibacterial use of Au@Ag NRs when coupled with light irradiation, which has not been previously described. 相似文献
999.
Hierarchical Hydrogen Bonds Directed Multi‐Functional Carbon Nanotube‐Based Supramolecular Hydrogels
Ran Du Juanxia Wu Liang Chen Huan Huang Xuetong Zhang Jin Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(7):1387-1393
Supramolecular hydrogels (SMHs) are three‐dimensional networks filled with a large amount of water. The crosslinking force in the 3D network is always constructed by relatively weak and dynamic non‐covalent interactions, and thus SMHs usually possess extremely high susceptibility to external environment and can show extraordinary stimuli‐responsive, self‐healing or other attractive properties. However, the overall crosslinking force in hydrogel networks is difficult to flexibly modulate, and this leads to limited functions of the SMHs. In this regard, hierarchical hydrogen bonds, that is, the mixture of relatively strong and relatively weak hydrogen bonds, are used herein as crosslinking force for the hydrogel preparation. The ratio of strong and weak hydrogen bonds can be finely tuned to tailor the properties of resultant gels. Thus, by delicate manipulation of the overall crosslinking force in the system, a hydrogel with multiple (thermal, pH and NIR light) responsiveness, autonomous self‐healing property and interesting temperature dependent, reversible adhesion behavior is obtained. This kind of hierarchical hydrogen bond manipulation is proved to be a general method for multiple‐functionality hydrogel preparation, and the resultant material shows potential for a range of applications. 相似文献
1000.