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61.
62.
为了降低制造业的生产成本,提高收益,在分析生产物流配线闲置和超载成本的基础上,采用粒子群算法对其进行优化,并利用模糊自适应改进惯性权值,通过实证研究表明该方法实用,可操作性强,可以有效降低制造业生产物流成本,具有广泛的应用价值。 相似文献
63.
针对突发事件下的应急物资调运问题,考虑了多个地区同时受灾以及多个出救点需要对其进行救灾并且各出救点的运力有限的情况,以最小化总的车辆运输费用,最大化救灾效率、各受灾点的救灾满意度,以及各受灾点得到救助的公平性为目标,建立了该问题的多目标混合整数非线性规划模型,并提出了一个基于两层架构协调的迭代式遗传算法进行求解。基于仿真数据的实验结果证明了所提出的模型和算法的有效性。 相似文献
64.
王艳 《无锡商业职业技术学院学报》2014,(1):106-109
目前,高职院校图书馆采编工作面临一些突出的现实问题,不仅影响到采编工作的质量效益和管理水平,也直接影响到图书、期刊与报纸等纸质资源的馆藏质量、广大师生读者满意率和图书馆窗口服务水平,引入ISO9000质量管理体系,并贯穿实施于整个采编业务的全过程,可以全面提升图书馆采编工作质量和管理水平。 相似文献
65.
Jaeyoung Jung R. Jayakrishnan 《International Journal of Sustainable Transportation》2017,11(8):567-581
Electric vehicles (EVs) are energy efficient and often presented as a zero-emission transport mode to achieve long-term decarbonization visions in the transport sector. The implementation of a sustainable transportation environment through EV utilization, however, requires the addressing of certain cost and environmental concerns such as limited driving range and battery-charging issues before its full potential can be realized. Nevertheless, a specific type of use of EVs, namely in taxi services, may elicit positive public opinion, as it promises a commitment toward sustainability in urban life. In light of this, this study proposes an integrated approach that combines EV operation with a conceptual design for shared-ride taxi services. As some productivity loss may be naturally expected due to the time spent in charging, it is important to look at whether such performance loss from the passenger and system standpoints can be offset with ingenuity in operational design. In this study, an EV taxi charge-replenishing scheme that can be coupled with a real-time taxi-dispatch algorithm is designed. The proposed EV charging schemes for taxi services are studied via simulations and the effects of the limited driving range and battery-charging details are examined from a system performance viewpoint. The simulation study also reveals illustrative results on the impact of the EV taxi fleet's operation on the charging system. Next, a real-time shared-taxi operation scheme that allows ride sharing with other passengers is proposed to maximize the operational efficiency. The simulation results suggest that the shared-taxi concept can be a viable option to improve on the limitations caused by EV operation. In addition, the importance of projected charging demands and queue delays at different charging locations are also addressed. Some limitations and a future research agenda are also discussed. 相似文献
66.
为利用投影寻踪(PP)技术科学,客观评价区域水资源可持续发展能力,基于生态环境、水资源和经济社会因素选取20个指标构建区域水资源可持续发展能力评价指标体系。利用新型仿生群体智能算法——凉亭鸟优化(SBO)算法优化PP技术最佳投影方向,提出SBO-PP水资源可持续发展能力评价模型,并构建灰狼优化(GWO)算法-PP模型、人工蜂群(ABC)算法-PP模型、差分进化(DE)算法-PP模型、地理生物学优化(BBO)算法-PP模型、粒子群优化(PSO)算法-PP模型作对比,以云南省2006—2015年及2020年水资源可持续发展能力评价为例进行实例研究。结果表明:SBO算法优化PP技术获得的适应度值优于GWO、ABC、DE、BBO和PSO算法,具有较好的求解精度、稳健性能和极值寻优能力。SBO-PP模型对云南省2006—2007年水资源可持续发展能力评价为"较差",2008—2015年评价为"中等",2020年评价为"较强"。 相似文献
67.
[目的]考虑环境和耕地约束,构建了城镇化效率测算指标体系,测算并分析我国2000~2014年区域城镇化效率,并且从城镇化发展模式与产业结构分布形态2个角度探索区域城镇化效率差异的机理。[方法]以"工业三废"和耕地面积减少量作为非合意产出,构建了由11个指标组成的投入—合意产出—非合意产出指标体系,进而利用优化ISBM模型测算了2000~2014年我国区域城镇化效率,并利用谱系聚类方法分析了其梯队层次特征。[结果]我国各省域城镇化效率总体较低,绝大多数省域处于效率缺损的状态;各省域城镇化效率表现为明显的5个梯队层次,不同区域、不同梯队省域城镇化效率存在明显差异,总体呈现出东、中、西依次递减的格局,并且省域之间城镇化效率差距自2000年以来呈不断缩小的趋势;东部地区城镇化效率较高,总体上城镇化与产业结构之间相互协调,城市群发展程度高而使得城市之间的分工合作程度高;中西部地区城镇化效率相对较低,产业结构对经济的支撑作用相对较弱,城市体系断层明显,城市群带动作用弱。[结论]我国区域城镇化效率总体较低且不平衡,这在很大程度上取决于城镇化模式和演进机制,区域之间的城镇化效率差异体现在产业结构层次、城市集聚方式以及劳动力转移方式等方面。 相似文献
68.
A network approach to modeling the multi-echelon spare-part inventory system with backorders and interval-valued demand 总被引:4,自引:0,他引:4
Eugene Levner Yael Perlman T.C.E. Cheng Ilya Levner 《International Journal of Production Economics》2011,132(1):43-51
A multi-echelon inventory system implies the existence of a hierarchy of stocking locations, and the dependence and interaction between them. We consider a multi-echelon, spare-part inventory management problem with outsourcing and backordering. The problem is characterized by deterministic repair time/cost, and supply and demand that lie within prescribed intervals and that vary over time. The objective is to minimize the total inventory and transportation costs. We develop a network model for problem analysis and present a network flow algorithm for solving the problem. We prove that the Wagner-Whitin property, known for the lot-sizing problem, can be extended to the spare-part inventory management problem under study. 相似文献
69.
《Socio》2016
Heuristic algorithms have been widely used to provide computationally feasible means of exploring the cost effective balance between grid versus off grid sources for universal electrification in developing countries. By definition in such algorithms however, global optimality is not guaranteed. We present a computationally intensive but globally optimal mixed integer non-linear programming (MINLP) model for electricity planning and use it in a Monte Carlo simulation procedure to test the relative performance of a widely used heuristic algorithm due to [28]. We show that the overall difference in cost is typically small suggesting that the heuristic algorithm is generally cost effective in many situations. However we find that the relative performance of the heuristic algorithm deteriorates with increasing degree of spatial dispersion of unelectrified settlements, as well as increasing spatial remoteness of the settlements from the grid network, suggesting that the effectiveness of the heuristic algorithm is context specific. Further, we find that allocation of off grid sources in the heuristic algorithm solution is often significantly greater than in the MINLP model suggesting that heuristic methods can overstate the role of off-grid solutions in certain situations. 相似文献
70.
In this paper, we propose a method for improving the accuracy of the estimation of interregional input–output tables, by combining the RAS method and the real-coded Genetic Algorithm (GA); these are simple representative methods for the estimation of an interregional input–output table. By comparing the performance evaluation results obtained using the proposed method, the RAS method, and Simulated Annealing, we verified that the combination of the genetic algorithm and the RAS method can enhance the estimation accuracy of an interregional input–output table. In addition, performance is further enhanced by adjusting GA parameters. 相似文献