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51.
Zhong  Gang  Yin  Tingting  Zhang  Jian  He  Shanglu  Ran  Bin 《Transportation》2019,46(5):1713-1736

The travel behavior of passengers from the transportation hub within the city area is critical for travel demand analysis, security monitoring, and supporting traffic facilities designing. However, the traditional methods used to study the travel behavior of the passengers inside the city are time and labor consuming. The records of the cellular communication provide a potential huge data source for this study to follow the movement of passengers. This study focuses on the passengers’ travel behavior of the Hongqiao transportation hub in Shanghai, China, utilizing the mobile phone data. First, a systematic and novel method is presented to extract the trip information from the mobile phone data. Several key travel characteristics of passengers, including passengers traveling inside the city and between cities, are analyzed and compared. The results show that the proposed method is effective to obtain the travel trajectories of mobile phone users. Besides, the travel behavior of incity passengers and external passengers are quite different. Then, the correlation analysis of the passengers’ travel trajectories is provided to research the availability of the comprehensive area. Moreover, the results of the correlation analysis further indicate that the comprehensive area of the Hongqiao hub plays a relatively important role in passengers’ daily travel.

  相似文献   
52.
目前,专家系统在国外的各行各业都得到了普遍应用。本文简要介绍了专家系统的概况优越性和未来的发展,较详细的介绍了专家系统在公路方面的应用。该文对我们推广应用专家系统在公路工程中的应用有一定的启迪。  相似文献   
53.
This study investigates different methods to visualise uncertainty in static representations of probabilistic traffic models predictions on road-networks. Although various graphical cues may be used to represent uncertainty it is not a priori clear which of them are most suited for this purpose, since their legibility, intelligibility and the degree to which they interfere with other graphical elements in a representation differ widely. Several graphical uncertainty representations were therefore developed and analysed in expert sessions. A selection of the initial set of uncertainty visualisations was further evaluated in a cognitive alternative task-switching experiment. The results show that graphical representations are able to convey uncertainty information relatively accurately, while some uncertainty visualisations outperform others. It depends on the model and scenario which representation is most suited for a given application. This paper presents an overview of possible graphic uncertainty representations and the considerations involved when applying them to uncertainty in traffic model visualisations.  相似文献   
54.
Transportation - Bicycling is an increasingly popular mode of travel in Canadian urban areas, like the Greater Toronto and Hamilton Area (GTHA). While trip origins and destinations can be inferred...  相似文献   
55.
If the Third United Nations Conference on the Law of the Sea succeeds in adopting a new Caracas Convention on the Law of the Sea, it is likely to embody detailed provisions on the delimitation of both the continental shelf and the new zone, the exclusive economic zone. In this paper, the most recent draft of these rules—contained in the Revised Single Negotiating Text—is subjected to a detailed and critical scrutiny which leads to the conclusion that the Sixth Session of the Conference still has a great deal of work to do before agreement can be reached on a satisfactory set of rules.  相似文献   
56.
This research attempted to analyze nanoparticles and other harmful exhaust emissions in accordance with injection strategies and air-fuel ratio (AFR) changes for small diesel engines. The emission characteristics were analyzed in the medium-speed condition, which is the main driving range of a diesel engine. In the case of particulate matter (PM), the number of particles was measured, analyzed, and compared to identify the correlation and emission characteristics of nanoparticles by using a dilution device and condensation particle counter (CPC), which are international standards for particle measurement recommended by the Particulate Measurement Programme (PMP). The engine torque tended to be reduced as pilot injections were added, and the torque was increased by the increased boost pressure, but reduced by the exhaust pressure increase in a part of the low-load range. The number of nanoparticles was not influenced greatly by the change in AFR, but the reduction effect on the PM weight was great depending on the boost pressure increase. In addition, the number of nanoparticles tended to increase as the fuel injection timing became closer to TDC in all conditions, and its difference became larger with an increase in AFR. In addition, in the case of the pilot injection, nanoparticle emission showed similar characteristics depending on the main injection timing, but it was increased by advanced injection timing when performing the main injection only, and the number of the nanoparticles increased as pilot injections were added. Last, the optimal conditions for EMS calibration were analyzed by selecting the conditions of torque reduction and NOx increase within 5 % from all of the engine operating conditions; optimized conditions are presented.  相似文献   
57.
通过常规阶段和奥运期间对出租车运行特征的监测与对比分析,研究奥运期间在交通限行背景下出租车出行规律和特征,评价出租车客运系统供给能力和运行效率,研究影响交通特征变化的有关因素,从而为今后大型活动的交通保障工作积累经验。研究结果表明,奥运期间出租车出车率达到92.26%,日均客运量较赛前增加19.2%,出租车空驶率由赛前的46.05%降低到37.06%;76.31%的受访者认为出租车运行速度较赛前有明显提高,而仅28.85%的受访者认为出租车候车时间明显变短,出租车服务水平还有待进一步提高。  相似文献   
58.
目的探讨中国汉族人群5-羟色胺转运体启动区(5-HTTLPR)基因多态性和抑郁症的发病、性别、严重程度及自杀是否相关。方法应用聚合酶链式反应(PCR)扩增技术测定150例抑郁症患者和150例正常对照者的5-HT-TLPR基因型和等位基因,分别验证各种基因型与中、重度抑郁症发病、性别及自杀行为的相关性。结果病例组SS、LS基因型及S等位基因频率均高于对照组(26.0% vs.20.0%;52.7% vs.46.0%;52.3% vs.43.0%;P均<0.05);两组性别分层比较,女性S等位基因频率高于对照组(55.3% vs.43.6%,P<0.05);病例组严重程度分层比较差异无统计学意义(P>0.05);病例组有无自杀行为分层比较,有自杀行为患者SS基因型频率(37.3% vs.20.2%)及S等位基因频率(61.8% vs.47.5%)均高于无自杀行为患者(P<0.05);抑郁自杀组性别分层比较未显示显著性差异(P>0.05);抑郁自杀组病情程度分层比较,重度抑郁自杀者SS基因型频率(42.5% vs.18.2%)及S等位基因频率(68.7% vs.36.4%)均高于中度抑郁自杀者(P<0.05)。结论在中国汉族人群中,5-HTTLPR多态性和抑郁症相关。S等位基因可能是抑郁症的易感基因,特别是女性,SS型可能是抑郁症易感基因型;S等位基因可能是抑郁症患者自杀的危险基因,SS基因型人群可能是抑郁症患者自杀的危险人群,特别是携带S等位基因的重度抑郁症患者更易自杀。  相似文献   
59.
以EQ491型发动机油底壳为研究对象,通过有限元法得到了油底壳模型的固有频率和振型,运用模态实验技术,验证了有限元模型的合理性。在原始有限元模型的基础上,对油底壳模型进行约束模态分析,验证了油底壳结构的合理性,即油底壳固有频率远大于发动机机体激振频率。  相似文献   
60.
随着风力发电机的容量不断提高,发电机的功率损耗和温升较为严重,双馈风力发电机中导电杆组件的温度变化较高,直接关系着整机的寿命和安全运行。通过有限体积法,结合导电杆组件各部分传热,仿真分析了瞬态传热时导电杆组件的温度场,结果表明,铜杆圆柱凸台与环氧树脂绝缘层存在最大的温度变化,产生的热应力容易损害导电杆组件。  相似文献   
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