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251.
Special unique database management and processing system (Oceanbase) have been developed to work with the large sets of multivariable interdisciplinary oceanographic and environmental data. AralBase system developed to work with the Aral Sea interdisciplinary data is a variety of the OceanBase. AralBase is a special database application with the expanded functionality designed to explore large multidisciplinary oceanographic and environmental data sets. It provides many possibilities for data loading, selection, access, processing, analysis, preview and export. The AralBase has a customizing user-friendly multi-windows interface. A user can create his/her own desktops and open and arrange as many windows as he/she needs.The most valuable feature of AralBase is the integration of many service tools that allow the user to carry out almost all data processing without any additional software. At the moment, the database is loaded with the oceanographic and meteorological data provided by the participants of the Inco-Copernicus Aral-Kum Project.The OceanBase system and the AralBase, in particular, are the very flexible systems, and they can be used in any environmental and oceanographic project or institution dealing with the water environment (ocean, lakes, rivers) data. The preloaded data bases with the Data Explorer system module can be distributed among the interested scientists and experts to simplify drastically their work with data. 相似文献
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Multimodal trip making, that is trips using a combination of several modes between origin and destination, is expected to be beneficial to society and might offer advantages to the traveler as well. This article looks at some of the implications of multi‐modality in trip making for the design of urban transit systems since these play an important role in multi‐modal transportation systems. In this respect, the article looks at the strategic design characteristics of urban transit networks, that is line density, stop density and service frequencies for the case of multimodal access to urban transit networks and for hierarchical network structures in urban transit systems. The analyses show that multimodal access does not require alternative network structures. For hierarchical network structures it is concluded that these are primarily determined by the hierarchy in demand densities and thus by hierarchy in urban structures. 相似文献
253.
Telecommuting and travel: state of the practice,state of the art 总被引:1,自引:0,他引:1
Patricia L. Mokhtarian 《Transportation》1991,18(4):319-342
This paper provides an overview of the status of telecommuting in the United States, especially as it relates to changes in travel behavior. Regarding the state of the practice, the paper discusses some refinements to the definition of telecommuting that have developed through increased operational experience. It reports several policy statements involving telecommuting, and explores the appeal of telecommuting as a public policy instrument. It highlights some trends in the implementation of home-based and work center-based telecommuting, and suggests that visible public-sector involvement has been crucial to the increased activity in this area.In sketching the state of the art, the paper outlines some frequently-stated hypotheses on telecommuting and travel behavior, and summarizes current empirical findings relating to those hypotheses. Finally, it suggests a variety of topics suitable for further research. These include studying factors influencing the ultimate adoption levels of telecommuting; impacts on energy/air quality, mode choice, and location/urban form; interactions with other transportation demand management strategies; relationships to the traditional urban travel demand forecasting process; cost/benefit tradeoffs; and telecommuting centers. 相似文献
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论述了通过一种新型磁阻式传感器测量汽车传动系统齿轮装置润滑油中的磨损颗粒含量的方法,以达到在线监测传动系统齿轮装置磨损程度的目的。 相似文献
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针对新型交通系统多编组智轨列车(Autonomous rail rapid transit,ART)由于车体过长而存在的安全隐患,基于8个单目相机传感器和2个铰接角度传感器,提出改进的图像配准方法以生成单车厢环视图像。结合图像映射原理与几何对齐技术融合铰接传感器角度数据实现整车全景环视图像的生成。研究结果表明:在单车厢环视图像生成过程中,改进的基于固定棋盘格内角点的图像配准方法配准精度与效率更高,且实际操作更简单;在多车厢环视图像生成过程中,本文所提出的方法被证明了在不同的铰接角时都能够有效且清晰地生成整车的全景环视图像,这对可视化大型多编组车辆视野盲区以及主动为驾驶员提供行车环境信息从而保证车辆安全驾驶具有重要意义。 相似文献
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后备控制模式是提高信号系统可靠性,保证其正常运营的重要手段之一。南京地铁二号线在西门子Trainguard MTA TC系统原有后备控制模式的基础上,又引入了中国电子科技集团公司第十四研究所研发的后备控制模式,使整个系统的可靠性得以提高。通过对多级后备控制模式的设计及原理进行分析,为今后进一步完善后备系统提供参考。 相似文献
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