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751.
752.
利用 GPS 技术、单片机和射频通信技术,完成了儿童定位和报警电路的设计与制作.本电路解析 GPS数据获得儿童的位置、速度信息,SD 卡存储轨迹信息,8位 ATmega 单片机完成距离的计算和逻辑判断,射频收发芯片完成儿童与监护人之间的数据传送,实现两者之间应答式的实时定位监护. 相似文献
753.
Arne Kesting Martin Treiber Martin Schnhof Dirk Helbing 《Transportation Research Part C: Emerging Technologies》2008,16(6):668-683
We present an adaptive cruise control (ACC) strategy where the acceleration characteristics, that is, the driving style automatically adapts to different traffic situations. The three components of the concept are the ACC itself, implemented in the form of a car-following model, an algorithm for the automatic real-time detection of the traffic situation based on local information, and a strategy matrix to adapt the driving characteristics (that is, the parameters of the ACC controller) to the traffic conditions. Optionally, inter-vehicle and infrastructure-to-car communication can be used to improve the accuracy of determining the traffic states. Within a microscopic simulation framework, we have simulated the complete concept on a road section with an on-ramp bottleneck, using empirical loop-detector data for an afternoon rush-hour as input for the upstream boundary. We found that the ACC vehicles improve the traffic stability and the dynamic road capacity. While traffic congestion in the reference scenario was completely eliminated when simulating a proportion of 25% ACC vehicles, travel times were already significantly reduced for much lower penetration rates. The efficiency of the proposed driving strategy even for low market penetrations is a promising result for a successful application in future driver assistance systems. 相似文献
754.
The scheduling operations of many paratransit agencies in the United States are undertaken manually. Those customers who are eligible to travel call in their requests the day before the trip is needed. As the trip requests are received, they are entered into a list of unscheduled trips. In order to schedule these trips, the scheduler must first determine the number of drivers and shuttle buses that are available as well as the time of availability of each. The scheduler must then try to match the rides that are in “similar” areas around the “same” time to place together on the driver's schedule. As new trip requests are made, the schedulers must adjust the trips that are already scheduled to try and schedule as many trips as possible in the most efficient way. By developing a system that would improve the scheduling system operations of, in this case, DART (Delaware Administration for Regional Transit) First State Paratransit, customers can expect to receive better service that will improve their ability to travel throughout the community. Some devices that could also improve the operations of paratransit agencies are described in this paper, such as satellite‐based Global Positioning System (GPS), radio communication systems, mobile computers, radio frequency‐based data communication systems, internet web pages, automated paratransit information systems, and card‐based data storage and transfer media. However, because paratransit systems are difficult to operate cost‐efficiently, the optimum and most cost‐efficient device must be selected. The system chosen for DART First State Paratransit includes the use of a relational database management system (RDMS) and a transportation Geographic Information System (GIS). RDMS keeps track of the database information as well as the scheduled trips and the GIS is ideal for analyzing both geographic and temporal data. This system is shown to be superior to the manual system. 相似文献
755.
汽车超载会严重破坏公路设施,增加公路维护费用,缩短公路使用寿命。构建货车限载自锁装置,将交通管理与车辆管理部门联合起来,可使车辆管理变得简单易行。 相似文献
756.
介绍GPS导航产品,概述导航产品的验证内容,结合实际重点探讨合理性/实用性验证和实车验证,提出一些方法和经验。 相似文献
757.
沪蓉西高速公路铁罗坪斜拉桥190m主塔为目前国内山区斜拉桥中最高的主塔,位于V字形山谷中,昼夜温差大,主塔施工受气候及环境影响大,施工控制测量是塔柱施工质量控制的关键之一。为了确保能够顺利地按照设计要求完成190m高主塔的施工,施工中通过研究国内其它高墩施工的测量技术,结合现场具体情况,总结出一套满足山区斜拉桥高墩测量的控制技术,特别深入研究探讨了对塔柱索导管采用GPS差分定位技术,供同类型桥梁施工借鉴。 相似文献
758.
759.
物流業中執行各種類型服務業務,在固定服務區域範圍來指派車輛,實施規劃合理的搬運工作;但無法確實要求搬運服務者,依事前規劃之排程及一些臨時性緊急性任務變動逐一實施服務,主要因為無法對已離場車輛實施即時掌控,導致離場車輛的任務指派、插入、刪除、變更等的調度工作增加許多複雜因素。論文架構針對:①離場車輛彈性調度的運用層面上,導入動態服務區域的規劃,使用排程演算配送順序,調整日單位車輛數及總車行距離;②利用FRID大量收集即時資料及GPS定位功能,掌握各服務區域內之搬運服務者的作業負擔量,同時對各服務區域內之車輛需求進行重新規劃;③運用即時電子看板(E-KANBAN)指派集結與新運送路徑,計算各車的運送距離並逐步整合服務區域,令各車的調度指派彈性增加。論文架構以3G無線網路實踐雙向通信的功能,透過電子看板傳遞與接收即時車載運送物品資信,擴大車控中心機能,操作排程及服務區域的動態規劃,逐步修正配送作業流程,達成車輛使用率遞減,降低運輸成本。 相似文献
760.
根据边坡地理条件和影响滑坡体的环境因素,可以利用各种监测设备对滑坡进行有针对性的监测。各种监测仪器的适用范围使监测设备在实际使用中,无法完全满足监测工程要求,因此可综合考虑多种监测方法,实现各种监测方法的优势互补,并通过各监测结果之间的对比印证,判断有效监测方案。在诸永高速公路深泽乡滑坡中,根据滑坡特征,采用了GPS与全站仪对滑坡体进行监测。监测结果表明,对于深泽乡滑坡情况而言,全站仪监测方案效率更高,在其他阶段监测工程中可作为优先考虑的方案。 相似文献