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11.
    
The use of smartphone technology is increasingly considered a state-of-the-art practice in travel data collection. Researchers have investigated various methods to automatically predict trip characteristics based upon locational and other smartphone sensing data. Of the trip characteristics being studied, trip purpose prediction has received relatively less attention. This research develops trip purpose prediction models based upon online location-based search and discovery services (specifically, Google Places API) and a limited set of trip data that are usually available upon the completion of the trip. The models have the potential to be integrated with smartphone technology to produce real-time trip purpose prediction. We use a recent, large-scale travel behavior survey that is augmented by downloaded Google Places information on each trip destination to develop and validate the models. Two statistical and machine learning prediction approaches are used, including nested logit and random forest methods. Both sets of models show that Google Places information is a useful predictor of trip purpose in situations where activity- and person-related information is uncollectable, missing, or unreliable. Even when activity- and person-related information is available, incorporating Google Places information provides incremental improvements in trip purpose prediction.  相似文献   
12.
    

This article reports on an implementation study of a computerised decision support system for public transport management for the Athens Public Transport Authority (APTA). The study analysed the current situation, specified user requirements, determined system functionality, designed the system architecture, organised the project and, finally, planned dissemination activities. The decision support system covers the main public transport management activities of APTA - transport service provision, economic and financial planning, passenger complaints and suggestions, and personnel management - offering its users the possibility to study the potential effects of their decisions before implementation. To achieve this, the system will consist of a data warehousing system, for the integrated management of a wide variety of data sources, and of online analytical processing tools, for information analysis and scenario testing. The system architecture has been designed to offer robustness, flexibility, rich functionality and open connectivity. The system aims to help APTA reduce operational costs and provide a better transport service, attracting more passengers to public transport and reducing, in the process, congestion and pollution.  相似文献   
13.
    
Growing concerns regarding urban congestion, and the recent explosion of mobile devices able to provide real-time information to traffic users have motivated increasing reliance on real-time route guidance for the online management of traffic networks. However, while the theory of traffic equilibria is very well-known, fewer results exist on the stability of such equilibria, especially in the context of adaptive routing policy. In this work, we consider the problem of characterizing the stability properties of traffic equilibria in the context of online adaptive route choice induced by GPS-based decision making. We first extend the recent framework of “Markovian Traffic Equilibria” (MTE), in which users update their route choice at each intersection of the road network based on traffic conditions, to the case of non-equilibrium conditions, while preserving consistency with known existence and uniqueness results on MTE. We then exhibit sufficient conditions on the network topology and the latency functions for those MTEs to be stable in the sense of Lyapunov for a single destination problem. For various more restricted classes of network topologies motivated by the observed properties of travel patterns in the Singapore network, under certain assumptions we prove local exponential stability of the MTE, and derive analytical results on the sensitivity of the characteristic time of convergence to network and traffic parameters. The results proposed in this work are illustrated and validated on synthetic toy problems as well as on the Singapore road network with real demand and traffic data.  相似文献   
14.
城市网约车订单需求体现了居民出行活力,同时表征了出行规律和内在特征。如何从复杂动态的时变数据中准确地识别异常点并进行调度优化,是优化网约车平台运力的关键环节。建立了网约车订单需求数据的时间序列图,并分析了订单需求的动态特性,提出1种基于混合机器学习框架的网约车订单需求预测模型(ARIMA-BPNN-DSR, ABD)。混合模型由差分整合移动平均自回归模型(auto regressive integrated moving average model,ARIMA)和反向传播神经网络(back propagation neural network,BPNN)通过动态选择回归算法(dynamic selection of regression,DSR)融合而成。混合模型汲取了统计方法的鲁棒性和机器学习方法的高效性,并考虑各个独立基线模型在数据局部空间上的性能表现。以2019年和2020年(疫情影响下)厦门市滴滴网约车平台订单数据作为试验基准并进行对比分析,结果表明:①与多个基线模型相比,ABD模型实现了最优的预测性能,同时在面向疫情外部因素影响下同样表现出优异的性能;②消融实验表明,在常规序列中,BPNN对融合模型的预测性能增益更高。混合模型相比较单独的ARIMA和BPNN模型,在预测性能指标上,平均绝对误差(mean absolute error,MAE)分别提高22.77%和13.50%,均方百分比误差(mean absolute percentage error,MAPE指标分别提高21.71%和12.37%。另外,在受到2020年的外部干扰下,ARIMA提供的稳定性至关重要;③预测结果与观测值之间的残差结合3-sigma异常检测准则实现订单数据中的需求突增异常点自动识别,以此提高交通管理效率。该结果说明,提出的ABD模型具有良好的预测精度和鲁棒性。  相似文献   
15.
王娜 《汽车实用技术》2022,47(16):152-156
以安徽三联学院机械工程学院的汽车构造网络线上教学为例,对线上教学模式开展方 法进行分析,以腾讯课堂为依托进行同步直播,以超星学习通为依托进行异步自学,并在讲 授中以问题导向为引导,加入多种互动方式进行互动连接,在内容梳理上引入思维导图,取 到了较好的效果。为实施稳定、有序、高效的线上教学模式提供借鉴。  相似文献   
16.
广州地铁3号线(北延段)非联锁站使用艾默生UHA1R-0050L型小功率UPS,由于单机运行故障率偏高,且无独立维修旁路,无法进行在线维修、更换,为此实施了UPS并机改造,提高了负载设备供电的可靠性。  相似文献   
17.
    
Autonomous and connected vehicles are expected to enable new tolling mechanisms, such as auction-based tolls, for allocating the limited roadway capacity. This research examines the public perception of futuristic auction-based tolling systems, with a focus on the public acceptance of such systems over current tolling practices on highways (e.g., dynamic and fixed tolling methodologies). Through a stated-preference survey, responses from 159 road-users residing in Virginia are elicited to understand route choice behavior under a descending price auction implemented on a hypothetical two-route network. Analysis of the survey data shows that there is no outright rejection of the presented auction-based tolling among those who are familiar with the current tolling methods. While males strongly support the new method, no clear pattern emerges among other demographic variables such as income and education level, and age. While high income respondents and regular commuters are more likely to pay higher tolls, no statistical significance between different genders, age groups, household sizes, and education levels is found. Based on the modeling results and the hypothetical road network, it is found that descending price tolling method yields higher average toll rates, and generates at least 70% more revenue when travel time saving is 30 min, and improves capacity utilization of the toll road significantly compared to fixed tolls.  相似文献   
18.
目前铁路电务部门主要依靠人工和机务故障报修系统的提报信息,对动车组司机操控信息分析系统(EOAS)车载设备进行维护,但无效及误报信息较多,无法满足当前车载设备的运用保障需求。针对该问题,基于故障预测与健康管理(PHM)技术,利用EOAS实时回传的车载设备运行数据和图像信息,通过通用故障建模、大数据技术、图像识别,智能分析运行状态变化,实现EOAS车载设备健康状态在线实时监测、关键部件的故障报警及预测、EOAS全生命周期的健康信息管理,为设备日常运用、维护和管理提供技术手段,实现精准和预防性维修,把当前被动的故障处理转变为故障预防管理。该系统投入运用后,对相关设备维护人员的知识储备、经验能力、熟练程度等要求大大降低;与原人工检测作业对比,检测耗时大幅缩短,有效提升电务部门的设备维护效率和质量,保障了车载设备的持续可靠运行。  相似文献   
19.
本文从服务旅客、业务管理和系统监控等角度对互联网售票系统进行了需求分析,提出了基于现有铁路客票系统、12306网站、铁路电子支付平台和站车无线交互平台构建互联网售票系统的总体方案,论述了系统的逻辑结构设计、系统功能设计、网络结构设计和关键业务流程设计,最后介绍了系统投产后的运行概况、存在的问题及下一步的研究重点.  相似文献   
20.
介绍了由谐振非接触供电模块、应变片扭力检测模块、信号无线收发模块等组成的扭矩信号采集装置,将其应用在船用柴油机的曲轴扭矩检测。通过试验,实现了对船用柴油机曲轴扭矩检测系统的输出电压计应变量的连续采集,完成了对船用柴油机曲轴扭矩的在线实时检测。该装置性能可靠、精度高、实时性好,在轮机管理方面具有较好的实际应用价值。  相似文献   
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