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501.
A fuzzy stochastic approach to the multicriteria selection of an aircraft for regional chartering 下载免费PDF全文
Luiz Flavio Autran Monteiro Gomes Joao Erick de Mattos Fernandes João Carlos C. B. Soares de Mello 《先进运输杂志》2014,48(3):223-237
This article deals with the problem of decision support for the selection of an aircraft. This is a problem faced by an airline company that is investing in regional charter flights in Brazil. The company belongs to an economic group whose core business is logistics. The problem has eight alternatives to be evaluated under 11 different criteria, whose measurements can be exact, stochastic, or fuzzy. The technique chosen for analyzing and then finding a solution to the problem is the multicriteria decision aiding method named NAIADE (Novel Approach to Imprecise Assessment and Decision Environments). The method used allows tackling the problems by working with quantitative as well as qualitative criteria under uncertainty and imprecision. Another considerable advantage of NAIADE over other multicriteria methods relies in its characteristics of not requiring a prior definition of the weights by the decision maker. As a conclusion, it can be said that the use of NAIADE provided for consistent results to that aircraft selection problem. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
502.
This paper proposed a methodology to estimate rear‐end crash potential of the merging vehicles traveling in the merge lane, on the basis of the traffic data extracting from the available videotapes. First, we developed a binary logit model to identify drivers' merging behavior in the work zone merging area. Subsequently, the occurrence potential of rear‐end crash based on time‐to‐collision was computed between the merging vehicle and its neighboring vehicles. The overall crash potential of the merging vehicle was finally determined. It was found that the crash potential decreases with the remaining distance to work zone. Moreover, there will be a rear‐end crash potential of 4.0% if the merging vehicle fails to complete merging at the end of work zone merging area. If the merging vehicle takes an early merge, there will be a lower rear‐end crash potential (1.2%). These findings suggest that we should encourage merging vehicles to take early merges for improving the traffic safety in the work zone merging areas. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
503.
The impacts of household structure on the individual stochastic travel and out‐of‐home activity time budgets 下载免费PDF全文
The amount of time individuals and households spend in travelling and in out‐of‐door activities can be seen as a result of complex daily interactions between household members, influenced by opportunities and constraints, which vary from day to day. Extending the deterministic concept of travel time budget to a stochastic term and applying a stochastic frontier model to a dataset from the 2004 UK National Travel Survey, this study examines the hidden stochastic limit and the variations of the individual and household travel time and out‐of‐home activity duration—concepts associated with travel time budget. The results show that most individuals may not have reached the limit of their ability to travel and may still be able to spend further time in travel activities. The analysis of the model outcomes and distribution tests show that among a range of employment statuses, only full‐time workers' out‐of‐home time expenditure has reached its limit. Also observed is the effect of having children in the household: Children reduce the flexibility of hidden constraints of adult household members' out‐of‐home time, thus reducing their ability to be further engaged with out‐of‐home activities. Even when out‐of‐home trips are taken into account in the analysis, the model shows that the dependent children's in‐home responsibility reduces the ability of an individual to travel to and to be engaged with out‐of‐home activities. This study also suggests that, compared with the individual travel time spent, the individual out‐of‐home time expenditure may perform as a better budget indicator in drawing the constraints of individual space–time prisms. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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研究突发事件导致列车晚点情况下城市轨道交通列车运行调整问题.从乘客角度出发,提出了“首站控制”和“多站协调控制”两类列车运行调整策略.考虑列车能力约束和列车区间运行时间、追踪间隔时间等运行条件约束,以受突发事件影响的全部乘客等待时间最小为优化目标,建立了基于两类调整策略的列车运行调整模型,采用Lingo软件进行求解.以某简化线路为算例,与不采取控制策略相比,两类策略下乘客等待时间均节省约9%,结果表明了模型的有效性,能够为轨道交通列车运行调整提供辅助支持. 相似文献
506.
安全气囊是汽车约束系统的重要组成部分.为了使安全气囊在碰撞事故中能够很好的保护乘员,在车辆安全系统的开发阶段需要进行大量的安全气囊匹配试验.汽车正面安全气囊匹配试验主要包括100%重叠正面碰撞试验、40%偏置碰撞、30.角碰撞、正面柱碰撞和钻入碰撞等.在气囊的匹配试验中,需要对气囊展开的时间特性进行分析,以便不断优化约束系统的设计,达到在交通事故中保护车内乘员的目的. 相似文献
507.
环氧沥青混合料作为一种使用性能优异的高等级铺面工程材料,其热固性赋予沥青优良的物理、力学性能。然而环氧沥青在固化剂的官能团作用下,其化学反应复杂,反应过程受各种因素影响较大。从影响环氧沥青混合料性能的因素出发,通过超温、超时以及混合料在不同固化程度与试验温度条件下的试验研究,分析时间、温度等因素对环氧沥青混合料性能的影响,为九江长江二桥钢桥面环氧沥青混凝土铺装施工提供技术保障。 相似文献
508.
对非现场的交通执法,单纯依靠违章照片已不能满足市民、交警和管理者的需要,于是违法视频作为强有力的证据便成为了执法中不可或缺的一部分。通过对在客户端本地构建内嵌服务器和在数据中心搭建应用服务器形成双B/S模式的研究,结合非现场交通执法实践,分析和构建适用于各交巡警部门的交通违法视频管理系统,重点探讨了视频格式的压缩转换、GPFS存储、时间码的嵌入、视频分割、流媒体的播放等。 相似文献
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详细阐述了船舶与海洋工程结构物舱室间空气声隔声的测量与评价问题,并结合SEVAN300型浮式海上生产储油平台典型舱室间隔声测量,对混响时间、舱室间隔声量的测量等进行细致描述;结合ISO相关内容就评价过程中的单值评价量、粉红噪声修正和交通噪声修正等进行说明,为船舶与海洋工程结构物舱室间空气声隔声的测量和评价提供参考。 相似文献