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31.
《Expert systems with applications》2014,41(15):6701-6717
Partner selection and transportation scheduling are critical to the success of a Virtual Enterprise. Collaborative transportation is a promising strategy that can help many enterprises survive and thrive in today’s highly competitive market. To help decision makers establish and operate Virtual Enterprises more effectively, an innovative decision support system is proposed in this paper. First, new model for integration of partner selection and collaborative transportation scheduling in Virtual Enterprises is developed. This integrated optimisation problem is very dynamic in nature and it is required to optimise a number of interlinked sub-problems at the same time. Then, a novel Genetic Algorithm with a unique dynamic chromosome representation and genetic operations is developed to find an optimal solution to the integrated problem. The effectiveness of the proposed approach is demonstrated in a representative case study. 相似文献
32.
针对综合交通网络评价指标权重及属性值具有主观性和随机性的特点,提出了基于模拟运算的布局规划方案排序选优的群体随机决策方法.仿真生成满足集结的多个专家对指标重要性偏好排序统计分布的权重,同时考虑交通需求的不确定性对指标值的影响,结合客观熵权计算方案的综合评价值,由多次模拟得到的排序优势度确定方案的优劣差异.根据设计的仿真流程通过算例说明了方法应用的有效性,评价中考虑了主客观因素及随机性特征,可以为网络布局提供科学决策依据. 相似文献
33.
简要介绍先进的埋地管道防腐工艺——管道三层PE防腐,在埋地天然气管道、给排水管道中的应用,三层PE管道防腐工艺逐渐取代传统的管道防腐工艺。 相似文献
34.
城市慢行交通系统是现代城市交通系统的重要组成部分,随着多模式城市交通发展,建立便捷和高效的城市慢行交通网络系统成为现代城市解决交通问题和提升交通运行效率的关键措施。基于此,文中应用统一建模语言(UML)和地理标识语言(GML)建立城市慢行交通网络数据模型,提出一种统一的和一致性的交通地理要素定义和性质描述方法,并阐述基于GML的城市慢行交通网络的地理要素和关系表达。研究成果促进了城市交通地理数据的组织、表达、集成、共享和操作,对建立高效的城市慢行交通网络系统具有重要的理论价值。 相似文献
35.
Momoji Kubo Tsuguo Kubota Changho Jung Minako Ando Satoshi Sakahara Kenji Yajima Kotaro Seki Rodion Belosludov Akira Endou Seiichi Takami Akira Miyamoto 《Catalysis Today》2004,89(4):479-493
Recently, we introduced a concept of combinatorial chemistry to computational chemistry and proposed a new method called “combinatorial computational chemistry”, which enables us to perform a theoretical high-throughput screening of catalysts. In the present paper, we reviewed our recent application of our combinatorial computational chemistry approach to the design of new catalysts for high-quality transportation fuels. By using our combinatorial computational chemistry techniques, we succeeded to predict new catalysts for methanol synthesis and Fischer–Tropsch synthesis. Moreover, we have succeeded in the development of chemical reaction dynamics simulator based on our original tight-binding quantum chemical molecular dynamics method. This program realizes more than 5000 times acceleration compared to the regular first-principles molecular dynamics method. Electronic- and atomic-level information on the catalytic reaction dynamics at reaction temperatures significantly contributes the catalyst design and development. Hence, we also summarized our recent applications of the above quantum chemical molecular dynamics method to the clarification of the methanol synthesis dynamics in this review. 相似文献
36.
37.
Cooperative adaptive cruise control(CACC)vehicles are intelligent vehicles that use vehicular ad hoc networks(VANETs)to share trafc information in real time.Previous studies have shown that CACC could have an impact on increasing highway capacities at high market penetration.Since reaching a high CACC market penetration level is not occurring in the near future,this study presents a progressive deployment approach that demonstrates to have a great potential of reducing trafc congestions at low CACC penetration levels.Using a previously developed microscopic trafc simulation model of a freeway with an on-ramp—created to induce perturbations and trigger stop-and-go trafc,the CACC system s efect on the trafc performance is studied.The results show signifcance and indicate the potential of CACC systems to improve trafc characteristics which can be used to reduce trafc congestion.The study shows that the impact of CACC is positive and not only limited to a high market penetration.By giving CACC vehicles priority access to high-occupancy vehicle(HOV)lanes,the highway capacity could be signifcantly improved with a CACC penetration as low as 20%. 相似文献
38.
J. N. Armor 《Catalysis Letters》2007,114(3-4):115-121
Perspectives are offered for reducing the impact of huge amounts of CO2 produced today from power generation and transportation vehicles. The origins of the dilemma between the world’s increasing
use of hydrocarbons as an energy source and the cogeneration of CO2 which results as a co-product are discussed. Hydrocarbons will provide much of the fuel needs for these major, global industries
for the next 20 years and meet 60% of the world’s energy demand. With the growth of both power generation and transportation
vehicles around the world, CO2 levels will continue to increase in the atmosphere. Renewables such as wind, dams, and biomass will not be able to handle
all the energy demand. Technology breakthroughs are needed to reduce the world’s dependence on fossil fuels, which will be
aggravated by the drive to use more coal. Current approaches for removing CO2 are discussed as well as near term and future options with particular focus on how catalysis can offer some solutions. In
particular, solar photocatalysis based approaches offer a potentially viable energy solution. 相似文献
39.
首先介绍了面向智能交通系统(Intelligent Transportation System,ITS)的无线接入网网络结构和主要业务,对车路协同业务和PTT语音业务进行了分析和建模。然后根据不同业务的特点及QoS需求提出具有针对性的调度方案:对于车路协同业务,采用适应车速的动态调度方法;对于PTT语音业务,采用基于状态转换的调度方法;对于视频和其他对时延不敏感的数据业务,采用缓存请求的调度方式。最后在OPNET平台上对调度方法进行仿真,针对各种ITS业务得出延时、丢包率等性能曲线,验证了算法的有效性,这也为ITS接入网的网络设计提供了参考。 相似文献
40.