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1.
针对能源消耗严重和环境污染双重压力下的现象,提出对汽车企业零部件循环取货路径的优化建议.将CO2的排放量与满足汽车制造企业的生产需要相结合,根据货运车辆的碳排放需要选择合适的碳排放计算模型,分别建立不考虑碳排放的循环取货路径模型和考虑碳排放的循环取货路径模型,利用遗传算法及基本原理对所建模型进行算法设计,并运用Matl...  相似文献   

2.
针对汽车制造企业精益生产的要求,结合远距离汽车零部件供应商循环取货特点,从供应商集并中心选址、循环取货车辆路径的设计、汽车零部件远距离供应商循环取货流程设计、循环取货信息系统的设计和商务系统规划五个环节对远距离零部件供应商循环取货进行系统的研究。最后对W公司远距离零部件供应商循环取货进行实证研究。  相似文献   

3.
基于C-W算法的汽车零部件循环取货车辆路径优化研究   总被引:1,自引:1,他引:0  
针对汽车零部件取货具有多频次和时间窗限制的特点,利用先进的循环取货方式对零部件进行取货.并构建数学模型优化取货路径,利用C-W算法,获得符合所有约束条件的满意解.使其在配送总量一定的情况下,运输总里程大大降低,从而节约了运输成本.最后给出一个算例.  相似文献   

4.
信息化赋能传统物流行业的迭代升级,为解决由于汽车制造业独有的物流特点带来的运输难题,使循环取货速度提升、成本费用降低及物流车辆造成城市内部交通压力得到缓解,以汽车厂A在城市Q本地循环取货实际运输需求为基础,设计了基于改进的遗传算法用于汽车零部件运输的智能路径规划方法。利用循环物流过程中当月零部件需求量、供应商订单详情、选配运输车辆容载率、单车器具体积占比、时间窗需求等耦合性因素,使用大规模邻域搜索算法改进遗传算法,求解出应用Solomon数据算例的最优路径并于遗传算法相比较和厂A与供应商间实际运输需求的最优配送方案线路。实验结果表明,该方法在性能上具有显著优越性,数值仿真结果阐明了该方法的适用性和优化过程中的收敛情况。  相似文献   

5.
【目的】质押物配送是物流金融中存货质押融资业务的重要流程。优化质押物配送路径可以节省配送时间,减小质押物在途风险以及运输成本。【方法】以配送质押物的车辆运行总距离最小为目标,将其转化为带距离和容量约束的车辆路径问题(DCVRP),建立数学模型。针对粒子群算法(PSO)的优缺点,设计用于求解该问题的混合变邻域搜索粒子群算法(PSO-VNS)。【结果】利用该算法求解应用实例,与基本粒子群算法对比求解的算法收敛过程和所得配送路径方案。【结论】通过实例研究表明,所改进的PSO-VNS算法能够快速跳出局部收敛,其全局寻优能力得到改善,且收敛速度更快,能够较好地为质押物配送路径问题提供解决方案。  相似文献   

6.
【目的】质押物配送是物流金融中存货质押融资业务的重要流程。优化质押物配送路径可以节省配送时间,减小质押物在途风险以及运输成本。【方法】以配送质押物的车辆运行总距离最小为目标,将其转化为带距离和容量约束的车辆路径问题(DCVRP),建立数学模型。针对粒子群算法(PSO)的优缺点,设计用于求解该问题的混合变邻域搜索粒子群算法(PSO-VNS)。【结果】利用该算法求解应用实例,与基本粒子群算法对比求解的算法收敛过程和所得配送路径方案。【结论】通过实例研究表明,所改进的PSO-VNS算法能够快速跳出局部收敛,其全局寻优能力得到改善,且收敛速度更快,能够较好地为质押物配送路径问题提供解决方案。  相似文献   

7.
在分析具有同时送货和取货需求的车辆路径问题(VRPSDP)的基础上,建立VRPSDP数学模型,提出一种新的求解VRPSDP问题的蚁群禁忌混合优化算法(ACO-TS),并通过实验验证该算法的有效性和可行性.新算法首先采用蚁群算法产生阶段最优解,然后利用禁忌搜索算法对阶段最优解进一步优化.实验表明,新算法能够高效解决VRPSDP问题,并且具有较好的优化效果.  相似文献   

8.
【目的】质押物配送是物流金融中存货质押融资业务的重要流程。优化质押物配送路径可以节省配送时间,减小质押物在途风险以及运输成本。【方法】以配送质押物的车辆运行总距离最小为目标,将其转化为带距离和容量约束的车辆路径问题(DCVRP),建立数学模型。针对粒子群算法(PSO)的优缺点,设计用于求解该问题的混合变邻域搜索粒子群算法(PSO-VNS)。【结果】利用该算法求解应用实例,与基本粒子群算法对比求解的算法收敛过程和所得配送路径方案。【结论】通过实例研究表明,所改进的PSO-VNS算法能够快速跳出局部收敛,其全局寻优能力得到改善,且收敛速度更快,能够较好地为质押物配送路径问题提供解决方案。  相似文献   

9.
【目的】着力设计带相容性约束的车辆路径问题的高效启发式算法。【方法】针对带相容性约束的车辆路径问题的特点,提出了一种混合蚁群算法。该算法的核心由蚁群搜索和禁忌搜索组成,对蚁群搜索的状态转移公式和信息素更新规则进行了改进,并在蚁群搜索过程中加入了一个扰动机制,同时在禁忌搜索部分采用了新的邻域结构和禁忌规则。【结果】得到了关于带相容性约束的车辆路径问题的混合蚁群算法。【结论】通过多个算例对算法进行了测试,计算结果表明该算法具有很高的求解效率。  相似文献   

10.
运用Shapley值法模型,来解决汽车零部件循环取货收益分配问题,并综合考虑各合作企业的风险,投资和物流能力对收益的影响,计算出综合修正因子,改进传统的Shapley值法模型.结合实例,对改进的Shap-ley值法模型和传统的Shapley值法模型进行比较分析,得出改进Shapley值法模型的汽车零部件循环取货收益分配结果的更加合理.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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