排序方式: 共有108条查询结果,搜索用时 15 毫秒
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大学生课堂使用手机情况调查与对策研究 总被引:1,自引:0,他引:1
文章从大学生课堂上使用手机的现状出发,调查研究大学生课堂使用手机的行为,并进行原因剖析,提出了针对性的对策与建议。 相似文献
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提出并实现了一种基于手机定位轨迹数据的出行行程识别方法.通过速度对轨迹点进行划分,将低于一定速度阈值以下的轨迹点合并为候选停留位置,再利用距离阈值和时间阈值对候选停留位置进行合并,从而确定出真正的停留点,继而自动统计出行次数和出行时间.该方法解决了手机定位数据的定位漂移和抖动的问题,行程识别精度高,识别结果可为交通规划工作提供相关数据,并具有比传统交通调查方法更低的成本和更短的数据更新周期. 相似文献
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基于手机定位的高速公路事件检测方法研究 总被引:3,自引:0,他引:3
改善自动事件检测方法的检测率(DR)、误报率(FAR)和平均检测时间(MTTD),对于提高事件管理效率至关重要。在分析现有检测方法的基础上,提出基于手机定位的高速公路事件检测方法并给出一种检测算法。算法以在路车辆上每部手机的定位数据为基础,由此获取平均速度、速度标准差和速度变化系数作为特性参数,采用模糊综合评判方法判断道路交通运行状态,实现高速公路事件的自动检测。模拟实验证明了该算法的有效性。 相似文献
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Xingdong DENG Jianmin XU Bo WANG 《Journal of Transportation Systems Engineering and Information Technology》2009,9(4):145-150
In view of the increasingly serious traffic problems caused by motorcycles, several large and medium-sized cities in China implemented motorcycle forbidden ban. Taking Guzngzhou city as an example, the paper summarizes the major characteristics of the traffic mode transferring period. Meanwhile, the travel volumes transfering from motorcycles to other modes are estimated and the changes of residents' travel mode choice are analysed. Then, the existing problems of urban traffic are pionted out from the aspects such as public transit, motorcycle travel, freight transport, and taxi transport. Finally, some applicable countermeasures are put forward to solve the problems existing in the period of traffic mode transferring. The countermeasures research in this paper provides references for traffic planning and policy making both in Guangzhou and other similar cities. 相似文献
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Alex A. Kurzhanskiy Pravin Varaiya 《Transportation Research Part C: Emerging Technologies》2012,21(1):163-180
The paper presents an algorithm for the prediction and estimation of the state of a road network comprising freeways and arterials, described by a Cell Transmission Model (CTM). CTM divides the network into a collection of links. Each link is characterized by its fundamental diagram, which relates link speed to link density. The state of the network is the vector of link densities. The state is observed through measurements of speed and flow on some links. Demand is specified by the volume of vehicles entering the network at some links, and by split ratios according to which vehicles are routed through the network. There is model uncertainty: the parameters of the fundamental diagram are uncertain. There is uncertainty in the demand around the nominal forecast. Lastly, the measurements are uncertain. The uncertainty in each model parameter, demand, and measurement is specified by an interval. Given measurements over a time interval [0, t] and a horizon τ ? 0, the algorithm computes a set of states with the guarantee that the actual state at time (t + τ) will lie in this set, consistent with the given measurements. In standard terminology the algorithm is a state prediction or an estimate accordingly as τ > 0 or =0. The flow exiting a link may be controlled by an open- or closed-loop controller such as a signal or ramp meter. An open-loop controller does not change the algorithm, indeed it may make the system more predictable by tightening density bounds downstream of the controller. In the feedback case, the value of the control depends on the estimated state bounds, and the algorithm is extended to compute the range of possible closed-loop control values. The algorithm is used in a proposed design of a decision support system for the I-80 integrated corridor. 相似文献
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近年来由于无线射频对象辨识技术(RFID)的快速发展,使低成本、可大量部署的与可涵盖大面积的无线射频对象识别器有突破性的进展.由读取器(Reader)、感应器(Transponder)与中介系统(Middleware System)3者串联而成的无线射频对象辨识架构,将形成未来生产线自动化、物料管理与物流业的新兴架构.由国际组织EPCglobal Inc.所倡导的EPC Network是RFID应用的标准科技,目前世界各大零售通路商如Wal-Mart、Tesco及Metro、P&G、Gillette等皆积极参与电子商品条形码EPC(Electronic Product Code)的应用.本论文针对RFID技术的EPC网络架构,实作一套综合RFID智能手机、EPC网络的智能移动采购系统.使用者以具有RFID Reader的智能手机进行采购,Content Web Server与ODS Server负责记录EPC Code的商品数据,透过EPC网络的ObjectTracing功能将商品直接运送到使用者家中;或由家中的RFID冰箱主动通知使用者所需采购信息,传送至智能手机进行采购,完成电子交易. 相似文献
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针对手机控制及操作复杂的现实问题,通过灵活利用方位信息,开发将方位信息用于检索的基于移动末应用软件系统,达到减少手机操控负担的目的,验证通过方位信息检索对减轻手机的输入、操控负担和提高检索速度的有效性. 相似文献
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沈桢桢 《南通航运职业技术学院学报》2012,(3):126-128
通过分析当今中国学习英语的现状,结合构建主义理论、学习风格理论及实际英语教学中存在的问题,从学生和教师两方面论述了采用移动学习法学习英语的可行性,并介绍了使用三种常见的移动设备学习英语的具体方法,最终得出基于网络的英语移动学习在中国有着积极的作用和广泛的前景这一结论。 相似文献