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41.
在交通场景中采用一些预警措施能够有效地减少交通事故发生。例如,对车辆轨迹进行跟踪并预测车辆的驾驶行为,就是一个常用的预警方法。在对车辆进行跟踪的过程中,数据关联是很重要的部分,它可以对车辆的观测点和轨迹进行关联,从而更新车辆的轨迹,完成跟踪过程。在此背景下,提出了一种新的数据关联算法,即k近邻联合概率数据关联算法(k Nearest Neighbor-Joint Probability Data Association,kNN-JPDA)。实验结果表明,该算法能够较好地解决在交通场景下车辆数据的数据关联问题,在精度以及运行效率方面都有所提高。  相似文献   
42.
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   
43.
A future successful global marketer must develop an excellent quality marketing system that impresses users and continuously provides excellent, quality products in a timely manner through corporate management. In this study, the authors proposed the Customer Science Dual System, CS-TMNS & CS-SDSM. For the purpose of innovating strategic product development systems so called Customer Value Creative System, the Total Marketing Network System, CS-TMNS is established. In addition, for intelligent utilization of the established CS-TMNS, statistical science is incorporated so as to create the Strategic Designing Support Methods, CS-SDSM, as a new approach to the creation of wants that are vital to product planning and designing. Concretely, the author will also introduce the effectiveness of this system that reflects latent customer needs through scientific marketing application examples via Automobile Design Profile for the Younger Generation.  相似文献   
44.
Human-mediated seed dispersal is recognised as an important, but under-researched, issue. To assess the potential for tourists to act as unintentional seed dispersal agents, we reviewed published and unpublished data on seed dispersal via clothing, vehicles (cars) and in/on horses and donkeys, all of which can be used by tourists. Seeds from 754 species of terrestrial plants have been collected from these vectors, 15% of which are internationally recognised environmental weeds. Seeds were collected from personal clothing and equipment (228 species), the fur of donkeys and horses (42 species), horse dung (216 species) and vehicles (505 species). Most were herbs (429 species) or graminoids (237 species) and native to Europe. Annual Poa, White Clover, Kentucky Bluegrass and Yorkshire Fog were the most frequent species. There have been eight studies specifically on tourists, which identified 12 species on clothing, 26 on vehicles and 133 from horse dung. Methods that minimise the risk of tourists as human-mediated dispersal agents may therefore be appropriate for some tourism activities/destinations: suggestions are made. Further sampling using standardised experimental techniques is required to assess the relative risk associated with specific tourist activities and locations and determine which, and how much, seed is transported.  相似文献   
45.
设计并实现了一种求解基本车辆路径问题的无交叉遗传算法,阐述了无交叉遗传算法求解物流车辆路径问题的关键技术,包括编码方案、初始种群生成方案、适应度函数、种群选择方案和变异操作等;并对比了使用目标函数倒数法和目标函数做差法构造适应度函数时的求解效果。实验结果表明,给出的无交叉遗传算法在求解车辆路径问题上具有良好的性能。  相似文献   
46.
文章针对当前汽车柴油发动机产品在可靠性方面存在的主要问题,结合国家试验标准,通过列举某台国产汽车柴油机可靠性试验中出现的故障情况及排除措施,纠正此类可靠性试验保养操作中的常见误区,阐明进行汽车柴油机可靠性试验的重要性和必要性。  相似文献   
47.
通过对现代汽车反馈传感器信号检测的结果分析,总结目前机动车疑难故障诊断的新的方法和思路,对汽车维修中常见的无明显故障码的现象产生原因进行研究,提出了相应的解决办法和应对措施.对汽车反馈传感器波形检测的实车应用进行了有意义的探讨和论证.  相似文献   
48.
Disaster‐relief logistics consists of providing adequate emergency supplies rapidly to the affected people so as to minimize human suffering and death. This study empirically examines the impact that the shortage of fuel, a commonly encountered problem in many disaster situations, can have on the effectiveness of disaster‐relief logistics operations. We focus on investigating the following two issues: (1) whether the shortage of fuel is more damaging in attaining logistical goals than the equivalent‐sized shortage in emergency supplies themselves, and (2) what types of vehicles should be used when the fuel supply is limited. Results suggest that the shortage of fuel may be more damaging than the shortage of emergency supplies, and that smaller trucks may be preferred to larger trucks when the shortage of fuel becomes severe.  相似文献   
49.
This article employs an integrated discrete-continuous car ownership model to jointly forecast households’ future preferences on vehicle type, quantity and use, and to estimate greenhouse gas (GHG) emissions. The model system is estimated on a dataset collected from a web-based stated preference survey conducted in Maryland in 2014. The data contain vehicle purchase decisions and sociodemographic information of 456 households who were requested to state their future preferences over a 9-year period (2014–2022). In each time period, a respondent is faced to four alternatives that include the current vehicle, a new gasoline vehicle, a new hybrid electric vehicle, and a new battery electric vehicle. Intertemporal choices between conventional and “green” vehicles such as hybrid and electric cars capture dynamics in vehicle purchase decisions. Short run and medium-long run situations were predicted and compared based on the first 4-year data and the entire 9-year data of the dynamic panel. Vehicle GHG emissions were calculated correspondingly. We find the introduction of “green” vehicles makes a positive impact on car ownership and use, especially in a medium-long run. Two “green” taxation policies, gasoline tax and ownership tax, were proposed and their impact on vehicle use and emission reductions was evaluated. Results indicate that: (a) gasoline tax is a more effective way to reduce vehicle miles traveled and GHG emissions and (b) gasoline tax makes a higher impact on car use and emission reductions in the medium-long run, while ownership tax makes a higher impact in the short run.  相似文献   
50.
近年来,江苏省机动车保有量快速增长,污染物排放呈逐年上升趋势。但机动车污染防治工作仍停留在被动管理状态,未完全实现对在用车辆的多方动态监管,从而造成了现阶段"重检测轻维护"的局面。积极开展机动车维护制度的研究,找出切实可行的工作程序和管理办法,将有助于推进交通节能减排工作的开展。  相似文献   
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