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931.
932.
以新建铁路为例,详细论证了使用GIS管理铁路项目的可能性、必要性和优越性,提出了一套完整的解决方案,包括用户管理、对象授权、属性链接、资料共享、数据备份等,此方法具有较高的推广应用价值. 相似文献
933.
周暐 《铁路通信信号工程技术》2004,(3):9-11
本文首先剖析了驼峰无线机车信号系统中,信号复示关系建立与机车定位的关系,然后介绍点式查询应答器(简称:应答器)和全球卫星定位系统(GPS)这两种定位方式在机车走行定位方面的应用模式,最后,给出两种定位方式集成、融合后,在驼峰无线机车信号方面的应用实例及效果。 相似文献
934.
935.
936.
介绍在工程全长15.6km、主桥长4.58km的虎门大桥建设中,利用GPS定位技术进行桥梁的施工放样。实践证明,GPS定位技术确定的悬挂桥索塔、锚锭、连续刚构桥主墩和西岸引桥高墩的平面和高程点误差和相对点位误差均满足桥梁施工规范要求。同时也说明了在沿海平坦地区,采用施工椭球方法进行GPS三维坐标转换能获得良好的平面和高程转换精度。 相似文献
937.
公路建设工程日益增多,传统的测量方法已不能满足新的要求,因此,GPS以其高精度、快速度、低费用等优点在公路建设中得到了广泛的应用。 相似文献
938.
Legibility has long been recognized as an important factor in creating a good image of a city in individuals’ minds. This image is perceived to assist people in understanding the city, finding their way, and recalling the city. The quality of the image affects individuals’ abilities in way-finding. This is especially important for cosmopolitan and global cities such as London in order to preserve resources and time, manage travel costs, limit pollution (air or noise) and enhance these cities as places to live, work and visit. This research examines the cognitive maps of London drawn by a sample of its residents to discover how different modes of transportation and GPS usage could affect individuals’ urban images. Such research is useful for town planners, local government departments, and urban and transport planners because of the way it considers the legibility of London as and provides a tool to study individuals’ urban images. 101 participants were recruited with at least a two-year residency from both genders (38.6% females and 61.4% males) with the average age of 33.88 and S.D. = 10.63. The results suggest car use has a positive correlation with seeing London in city scale and GPS usage has a negative correlation. Whilst recent studies have shown that there are differences between active travel modes (e.g., walking, bicycle riding or driving a car) and passive modes (e.g., as a passenger taking a bus, train or taxi), this study indicates that GPS usage also influences cognitive maps, with a negative correlation found between GPS usage and drawing maps on a city scale. Other significant associations were found for the car drivers with a positive relation with the number of roads mentioned on the maps, seeing London in city scale and having a two-dimensional façade image of the city in mind. 相似文献
939.
This paper analyzes the effect of access and egress time to transport terminals over the spatial competiveness of the high-speed train (HST) in the Madrid–Barcelona (Spain) corridor, one of the densest airline domestic markets in the world. Applying spatial data from 2010 provided by a geographical information system (GIS) to a mode choice model estimated with sample travelers in this corridor, the present study examines whether and how the level-of-service of transport terminals spatially affects the competitiveness or modal distribution of HST and air transport in the provinces of Madrid and Barcelona; and, in particular, the degree of competitiveness that can be accrued by the access time provided by private car and transit in different market segments, especially mandatory and leisure trips. In a number of urban zones near train stations and airports, terminal accessibility clearly favors one transport mode in comparison to the other. Improving terminal accessibility via private car or public transit not only affects the relative access to terminals, but also represents a key strategy for readjusting the market shares of the competing modes in the corridor. 相似文献
940.
Particular safety problems relate to traffic on local streets. Local Area Traffic Management (LATM) schemes are often implemented with the objective of counteracting these safety problems. One analytical difficulty in appraising the effectiveness of LATM in dealing with safety problems has been the ‘footloose’ nature of accident locations in a local street network. Seldom are there distinct ‘blackspot’ locations. An area‐wide approach is needed and the interaction between the system and arterial road network must be considered. The paper describes the development of a Safety Evaluation Method for Local Area Traffic Management (termed SELATM). It is a GIS‐based program for analysing accident patterns over time and the evaluation of the safety benefits of LATM schemes. The evaluation is perform at different network levels for various accident variables. The thrust of the program involved the integration of network data with data on accidents and the installed devices to generate summary accident statistics for the various network levels allowing for before and after comparison with a control area. This program as developed is applied to a LATM scheme at Enfield, a suburb in metropolitan Adelaide. 相似文献