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111.
通过对福建省福鼎宁德段高速公路声环境现状的调查研究,采用类比分析的方法,确定其沿线所要保护的声环境敏感点,合理科学预测交通噪声对声环境的影响,提出减轻噪声污染的若干措施。 相似文献
112.
应用地质雷达技术和管道探摄仪探查管道病害 总被引:1,自引:0,他引:1
简单阐述了地质雷达探查技术的原理和管中探摄方法,结合具体工程实例,讲述了该技术在雨、污水管道病害探查中的应用。达到在不采取截流措施的前提下对雨、污水管道外部土体扰动情况及管道内部的完整性情况进行准确判断的目的。 相似文献
113.
常规汽油机上实现电控点火提前的研究 总被引:2,自引:0,他引:2
在分析了点火提前的机械控制和电子控制两种方法的特点以及电子控制方法中的自适应 控制的研究现状的基础上,提出了常规机械控制的汽油机上仅利用分电器输出的点火信号进行点提关自适应控制的理论和方法,并进行了该理论方法可行性研究。 相似文献
114.
合理的横断面形式、平纵线形指标、路基路面设计是城市道路改建中的关键。结合苏州老城区道路改建项目,针对现状建设条件、交通量预测结果,推荐采用三块板断面布置形式。通过拆除原侧分带、压缩非机动车道形式,使现状双向四车道实现双向六车道,同时新建侧分带保留了四排绿化,充分考虑了老城区道路绿化景观需求。拓宽新建段一般路基设计采用20 cm C20混凝土处理,路面设计根据现状弯沉值推荐了两种方案,为城市道路改建工程提供经验参考。 相似文献
115.
数据处理方法在路堤工后沉降预测中的应用 总被引:3,自引:1,他引:2
介绍了3种预测路堤工后沉降的模型及求解方法,并应用于工程实例中;把3种方法得到的结果与实测结果相比较,指出各种方法各有优点,各有其适用情况。 相似文献
116.
117.
Transit Traveler Information Systems (TTIS) comprise a wide range of technologies that transit agencies use to provide reliable and timely transit-related information to customers. The touch-screen interactive information kiosk is an example of these emerging TTIS technologies. This paper examines the implementation of interactive touch-screen information kiosks, known as “On the Go!” Touch-Screen Travel Stations, at Metropolitan Transportation Authority-New York City Transit (MTA-NYCT) facilities in 2011. It analyzes data from passenger intercept surveys, from the kiosks’ built-in application usage logs and from field observations to understand actual passenger utilization of the kiosks and to assess the implications for transit agencies. The field observations also made it possible to obtain a profile of kiosk users, which sheds light on the concept of the “digital divide.” The findings, presented as lessons learned, can help agencies elsewhere develop guidelines and effective strategies for implementing similar interactive transit information systems. 相似文献
118.
This paper develops an agent-based modeling approach to predict multi-step ahead experienced travel times using real-time and historical spatiotemporal traffic data. At the microscopic level, each agent represents an expert in a decision-making system. Each expert predicts the travel time for each time interval according to experiences from a historical dataset. A set of agent interactions is developed to preserve agents that correspond to traffic patterns similar to the real-time measurements and replace invalid agents or agents associated with negligible weights with new agents. Consequently, the aggregation of each agent’s recommendation (predicted travel time with associated weight) provides a macroscopic level of output, namely the predicted travel time distribution. Probe vehicle data from a 95-mile freeway stretch along I-64 and I-264 are used to test different predictors. The results show that the agent-based modeling approach produces the least prediction error compared to other state-of-the-practice and state-of-the-art methods (instantaneous travel time, historical average and k-nearest neighbor), and maintains less than a 9% prediction error for trip departures up to 60 min into the future for a two-hour trip. Moreover, the confidence boundaries of the predicted travel times demonstrate that the proposed approach also provides high accuracy in predicting travel time confidence intervals. Finally, the proposed approach does not require offline training thus making it easily transferable to other locations and the fast algorithm computation allows the proposed approach to be implemented in real-time applications in Traffic Management Centers. 相似文献
119.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):305-325
This paper presents the results of an experimental and numerical investigation on the derailment of a railway wheelset with solid axle. Tests were carried out under quasi-steady-state conditions, on a full-scale roller rig, and allowed to point out the effect of different parameters like the wheelset's angle of attack and the ratio between the vertical loads acting on the flanging and non-flanging wheels. On the basis of the test results, some existing derailment criteria are analysed in this paper and two new criteria are proposed. A model of wheel–rail contact is proposed for the mathematical modelling of the flange climb process, and numerical vs. experimental comparisons are used to obtain model validation. 相似文献
120.