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751.
台湾因人口集中都会区且道路年增率远不及车辆年增率,形成都会区内及城际道路交通日益频繁与拥塞,台湾目前陆运交通主流与世界趋势相同,主要以轨道运输系统为陆运交通主要解决方案,同时近年来在降低环境污染及增加能源使用效能之呼声下,更使得铁路运输亦再度成为最佳解决方案.近年来台北捷运系统中和线古亭站穿越民房下方潜盾隧道段、维修线中华路区段及板桥线西门站至龙山寺站地下隧道,沿线接获越来越多居住其上的居民对振动噪音污染生活质量之抱怨与不满,同时因民众环保意识的日渐抬头,民众对捷运行驶的噪音愈来愈不能忍受,噪音陈情的地点也愈来愈多,目前虽采取许多改善措施,但似乎不能满足沿线居民的需求.此篇论文即针对轨道运输系统中台北捷运地下隧道分轨道噪音之成因进行分析,并经分析评估,拟定出各轨道噪音案在地下隧道的防治对策,并对部分防治对策做-长期监测,并对部分监测数据进行初步分析比对,厘清对策与成因在理论上及实务上之成效比对,从而进行设计上之回馈,以提供轨道运输在环境噪音防治之最佳方案.  相似文献   
752.
The commonly used 'uniform pressure method' (UP) is a well-tried method to simulate an airbag deployment in accident cases. Nevertheless, this method indicates rather heavy inadequacies at the examination of the airbag deployment in the first milliseconds. A solution is the airbag deployment calculation by using computational fluid dynamics (CFD) methods, wherein the calculated gas flow pressure may be applied 'correctly' to the airbag shell elements.

This CFD simulation is integrated in LS-Dyna with the so-called Arbitrary Lagrangian Eulerian (ALE) method and in this review the result's accuracy will be discussed. According to the FMVSS 208, an OoP model will be built-on and comparisons with simulations and tests are done. Another important detail in this labour is the airbag cover examination and the tear seam modelling, as a trivial FE modelling cannot be done due to the very fine mesh. So two possible solutions for tear seam modelling are introduced and discussed. Furthermore considerations concerning the gas generator combustion will also be revealed and an analysis about the impossibility of the direct comparison between gas generator tank test and airbag deployment will be done. At least some parameters, which take effects in the simulation, are researched and evaluated, so finally an optimised simulation model can be made available for further examinations.  相似文献   
753.
台湾近年来新兴轨道运输系统方兴未艾,都市轨道运输系统,因其路线多经过都市闹区,故常采用地下型式兴建,当发生意外事故或灾变时,乘客能否安全逃生必须倚赖系统对隧道内与地下车站之乘客安全疏散所设计的逃生设备及事前完备规划的操作程序;目前台北捷运系统在隧道段及地下车站之灾害处理对策部份,已属成熟,由于台北捷运系统为台湾都会区轨道运输系统最先施作者,其规划设计除参考国外捷运系统之相关规划设计准则外,并融合台北都会区域活动特性而订定了台北捷运系统地下隧道乘客逃生操作程序,本文将台北捷运系统规划隧道安全疏散程序及地下车站乘客疏散原则,作一全面性说明及分析,希望能提供国内其它轨道运输隧道系统安全规划之案例参考.  相似文献   
754.
In this article, vehicle dynamics integrated control algorithm using an on-line non-linear optimization method is proposed for 4-wheel-distributed steering and 4-wheel-distributed traction/braking systems. The proposed distribution algorithm minimizes work load of each tire, which is controlled to become the same value. The global optimality of the convergent solution of the recursive algorithm can be proved by extension to convex problems. This implies that theoretical limited performance of vehicle dynamics integrated control is clarified. Furthermore, the effect of this vehicle dynamics control for the 4-wheel-distributed steering and 4-wheel-distributed traction/braking systems is demonstrated by simulation to compare with the combination of the various actuators.  相似文献   
755.
This paper presents a new model which studies probability distributions of queue lengths at fixed time traffic signals. It extends Haight's model for Poisson arrivals that the arrival distribution during the effective red period is general and the headway between two successive departures is not less than the minimum departure headway. Moreover, the probability generating function of the queue length, at the end of the effective red period, is derived. The probabilities of the queue lengths, at the ends of the effective green, actual red and amber periods, are also obtained. Comparison is made with Haight's model. Finally a case study for the proposed model is reported.  相似文献   
756.
This article deals with the simulation of a vehicle/pilot system experiencing external disturbances. In the simulation, the car is modeled with two degrees of freedom and the pilot is assumed to respond to the state vector with a time delay. When perturbations are introduced, the pilot is expected to drive his car back to the initial state while minimizing a quadratic cost function. With some simplifications for low frequencies responses, the model is then used to simulate the response of different vehicles to an initial step in lateral displacement. The results from the simulations are interpreted in the light of the controllability diagrams.  相似文献   
757.
758.
This United States stands alone amongst the nations of the world in its attempt to unilaterally regulate transnational ocean linear services. The major reason for current US regularity policies with regard to scheduled ocean transportation lies in its fundamental distruct of any form of co-operation amongst competitors as demonstrated by its history of antitrust legislation.

The linear industry, because of its unique technical and economic charectersitics has given rise to the establishment of ocean conferences—co ordinating sgreements between the operators of linear vessels. Whilst ocean conferences are permitted—even encouraged—by the their most diluted form, the so-called 'open conferences.

This Paper offers a critical review of Successive US regulatory practices in maritime transport. It is argued that these practices result in excess costs in US trades to the order of $1 billion annually, and that the linear industry's efficient functioning is seriously impaired by these rules-rules imposed by a government administration which fails to recognize that the linear industry's technical efficiency is of far greater importance than its market performance.  相似文献   
759.
This note shows, with an example, that user costs on transportation systems need not remain constant or increase with increasing volume, even with design and operational options fixed.  相似文献   
760.
It is quite challenging to estimate the braking performance of a vehicle because the brake system is comprised of many parts, including a booster, master cylinder, and caliper. Calculation of characteristics such as braking force through vehicle tests requires much time and money. Therefore, the development of a method to estimate the braking performance of a vehicle using qualitative methods is beneficial. In this study, a program that can analyze the braking capabilities of a vehicle such as pressure, efficiency, and pedal travel is presented. The increase in disc temperature during braking as well as the properties of various boosters can be calculated using the proposed program. Dynamic characteristics of a vehicle equipped with a Load Sensing Proportional Valve (LSPV) were computed more precisely by obtaining the change in valve pressure according to the displacement of a suspension system. Since all input and output files are composed in the Microsoft Excel format, both design data management and database construction can easily completed.  相似文献   
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