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21.
基于经验模式分解的钢轨波浪弯曲不平顺提取方法 总被引:5,自引:3,他引:2
钢轨波浪弯曲不平顺隐藏在轨道不平顺中。采用小波分析和经验模式分解相结合的方法,对钢轨波浪弯曲不平顺进行识别和提取分析。利用对称双正交小波对轨检车监测到的车体垂向加速度响应和高低轨道不平顺信号进行小波变换,滤除波长1 m以下成分后,基本可以保证用经验模式分解得到的第1个固有模态函数包含全部钢轨弯曲不平顺信息。对提取得到的钢轨波浪弯曲不平顺的分析表明,不同钢轨上存在的弯曲不平顺不同,钢轨存在的波浪弯曲不平顺是波长在3 m附近变化的准周期不平顺;钢轨波浪弯曲不平顺是引起车体颤振的原因。建议在提速线路和客运专线上应限制波浪弯曲钢轨上道。 相似文献
22.
本文重点介绍了采取新的思路将现有医院触摸屏查询系统扩展运用于住院医保患者自付费用的实时核查,并将运算结果进一步共享运用在医院信息系统(HIS)各个功能模块。 相似文献
23.
广州公路桥梁养护管理模式探讨 总被引:1,自引:0,他引:1
搞好桥梁养护工作的重点,就是要建立一种与本地区经济发展及养护机制相适应的养护管理模式,广州公路养护管理模式的建立与成功运用,确保了在养10000多座桥梁长期的安全和畅通。 相似文献
24.
Kåre Rumar 《Transportation》1990,17(3):215-229
Initially the driver's role as a link in the driver-vehicle-road-traffic control-chain is discussed in a historical perspective. The gradual changes and the advantages and problems arising from these changes are discussed from behavioural point of view.Then the driver tasks are analyzed. A separation is made between trip planning, navigation, road following, traffic interaction, rule compliance, other than traffic tasks, car handling and speed choice. The relations between and the weights of these subtasks are discussed. Some existing driver behaviour models are reviewed in relation to the above mentioned tasks.Finally an effort is made based on the analyses of driver tasks and driver models to specify some general and some more specific potential advantages and problems with expected future RTI-systems. 相似文献
25.
Hironao Kawashima 《Transportation》1990,17(3):263-284
A perspective view of of Japanese R&D activities of Driver Information Systems is given from the standpoint of developing joint projects by public and private sectors. First, a brief history of the R&D activities is illustrated from above mentioned standpoint. Then, two major projects, AMTICS and RACS, and the social backgrounds of these projects are explained. In order to give a clear idea of both projects some technical details are treated.Based on the history and the present status of the developments, the basic design conceptions of Japanese Driver Information Systems are explained and several factors or reasons which have influenced to the design conception are discussed. Then, the promoting systems of the R&D activities are generally explained and present status of the projects and future problems in developing more advanced systems are also handled. A brief discussion on the establishment of international standard is also mentioned as a final comment. 相似文献
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27.
详细地对机务管理信息系统进行了分析,指出了系统运行环境和主要技术功能,为机务管理部门进行现代化管理提供了很好的借鉴。 相似文献
28.
Discusses and analyzes the causes and characteristics of the uncertainties of the information and actions for preventing collision at sea on the basic knowledge of the collision avoidance.Describes the ways and functions of the investigations about the uncertainties of the information and actions of collision avoidance with the navigation simulators.Puts forward some suggestions for the officers to master the skills of the recognition of these uncertainties of the information and actions by the training with the sim- ulator during the MET course. 相似文献
29.
In mode choice decision, travelers consider not only travel time but also reliability of its modes. In this paper, reliability was expressed in terms of standard deviation and maximum delay that were measured based on triangular distribution. In order to estimate value of time and value of reliability, the Multinomial and Nested Logit models were used. The analysis results revealed that reliability is an important factor affecting mode choice decisions. Elasticity is used to estimate the impacts of the different policies and system improvements for water transportation mode. Among these policies, decision maker can assess and select the best alternative by doing the benefit and cost analysis based on a new market share, the value of time, and the value of reliability. Finally, a set of promising policies and system improvement of the water transportation were proposed. 相似文献
30.
MapX在电子海图中的应用与实现 总被引:7,自引:1,他引:6
研究MapX的特点,应用MapX实现了电子海图中GIS的功能,并以船舶监控系统中GIS分析部分为例,实现了图层操作,海图要素拾取、添加,船舶监控,轨迹回放等功能。 相似文献