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81.
In recent years, there has been increased interest in using completely anonymized data from smart card collection systems to better understand the behavioural habits of public transport passengers. Such an understanding can benefit urban transport planners as well as urban modelling by providing simulation models with realistic mobility patterns of transit networks. In particular, the study of temporal activities has elicited substantial interest. In this regard, a number of methods have been developed in the literature for this type of analysis, most using clustering approaches. This paper presents a two-level generative model that applies the Gaussian mixture model to regroup passengers based on their temporal habits in their public transportation usage. The strength of the proposed methodology is that it can model a continuous representation of time instead of having to employ discrete time bins. For each cluster, the approach provides typical temporal patterns that enable easy interpretation. The experiments are performed on five years of data collected by the Société de transport de l’Outaouais. The results demonstrate the efficiency of the proposed approach in identifying a reduced set of passenger clusters linked to their fare types. A five-year longitudinal analysis also shows the relative stability of public transport usage.  相似文献   
82.
The existing studies concerning the influence of weather on public transport have mainly focused on the impacts of average weather conditions on the aggregate ridership of public transit. Not much research has examined these impacts at disaggregate levels. This study aims to fill this gap by accounting for intra-day variations in weather as well as public transport ridership and investigating the effect of weather on the travel behavior of individual public transit users. We have collected smart card data for public transit and meteorological records from Shenzhen, China for the entire month of September 2014. The data allow us to establish association between the system-wide public transit ridership and weather condition on not only daily, but also hourly basis and for each metro station. In addition, with the detailed trip records of individual card holders, the travel pattern by public transit are constructed for card holders and this pattern is linked to the weather conditions he/she has experienced. Multivariate modeling approach is applied to analyze the influence of weather on public transit ridership and the travel behavior of regular transit users. Results show that some weather elements have more influence than others on public transportation. Metro stations located in urban areas are more vulnerable to outdoor weather in regard to ridership. Regular transit users are found to be rather resilient to changes in weather conditions. Findings contribute to a more in-depth understanding of the relationship between everyday weather and public transit travels and also provide valuable information for short-term scheduling in transit management.  相似文献   
83.
Remote user authentication is essential in distributed network environment to protect unauthorized access of a networked system. However, most of those existing remote user authentication schemes have not provided the user identity anonymity, while user anonymity is particularly important in some practical applications. Therefore, based on self-encryption mechanism, a new remote user authentication scheme was proposed. The scheme not only has no need of maintaining a password table at the remote server, but also can protect the user's anonymity.  相似文献   
84.
在机车的显示与诊断系统中,使用高分辨率平板显示器已成为一种趋势。本文详细介绍了等离子体显示屏及其驱动系统的工作原理。  相似文献   
85.
研究并设计了一种可联机使用也可单独使用的高安全性的无线IC卡读写模块,它以AT89C51单片机为微控制器,以MFRCS00芯片为IC卡读写器,构建了一个使用简单的IC卡读写系统。该系统基于MFRC500芯片构成读写模块,并对微控制器与读写芯片的通信方式作了详细介绍。该系统的最大特点在于其通信过程中使用高安全性的数据加密算法。  相似文献   
86.
Introduction Remoteuserauthenticationschemesarevery usefulindistributedsystemssincetheycanguar-anteeonlythelegalusershaverighttovisitthere-sourcesprovidedbytheremoteservers.There-fore,overthepastyears,manyremoteuserau-thenticationschemes[1-8]havebeenproposed.In1981,Lamport[1]proposedthefirstwell-known passwordauthenticationschemeusingapassword tabletoachieveuserauthentication.However,Lamport'sschemesuffersfromtheriskofamodi-fiedpasswordtableandthecostofprotectingand maintainingthepasswordtabl…  相似文献   
87.
结合BP神经网络的建模方法,首次提出跨区消费分布矩阵的推算模型,并根据实际应用情况来设置误差阀值和学习率等关键参数,通过训练实际一卡通消费数据,得到跨区消费分布矩阵,实际输出数据误差在允许的范围内.实验表明该模型适用于跨区消费分布情况的预测,可为省域公交一卡通提供重要的决策支撑数据.  相似文献   
88.
89.
交通一卡通目前在全国范围内已经大范围普及,但是一卡通的应用较为单一,主要是用于交通支付和小额支付.针对目前城市普遍存在的交通拥堵问题,本文对北部湾经济区交通一卡通在交通管理领域的应用进行研究,挖掘一卡通的交通管理功能.交通一卡通在交通管理领域的应用将提高交通管理技术,并缓解城市交通拥堵.  相似文献   
90.
广东省高速公路发展迅猛,联网收费正从区域联网向全省联网逐步实现。通行卡作为收费唯一的介质,作用十分突出。尽管各高速公路路段都有严格的通行卡管理制度,但由于部分路段的收费系统使用年限较长、个别路段所采用的半自动卡机模式、卡箱陈旧、部分入口发卡亭没有安装监控系统等问题,导致通行卡管理存在管理疏漏。探讨我省高速公路通行卡管理采取哪些有效措施防范,从而获得较高的经济效益。  相似文献   
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