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111.
近年来,北京城市轨道交通建设发展速度加快,对缓解交通拥堵、提升公共交通出行效率、提高交通出行的准时性起到重要作用,但在一体化方面还存在不足。通过对北京城市轨道交通一体化进行专项调查研究,选取110个轨道站点,获取线下调查样本2 400份、线上调查样本约1 000份,系统分析北京市轨道交通一体化和便利性的现状。针对调查分析结论,提出提升轨道交通一体化的对策建议:加强初始统一规划设计,优化交通枢纽布局和运营衔接,深化既有站点服务水平,推动站点接驳功能修补等。  相似文献   
112.
Currently, as well as in the past, researchers have shown great interest in developing suspension systems for vehicles and especially in the design and optimization of the suspension parameters, such as the stiffness and the damping coefficient. These parameters are considered to be important factors that have an influence on safety and improve the comfort of the passengers in the vehicle. This paper describes a simplified methodology to determine, in a quick manner, the suspension parameters for different types of passenger cars equipped with passive suspension systems. Currently, different types of passenger cars are produced with different types of suspension systems. Finding a simplified methodology to determine these parameters with sufficient accuracy would contribute a simplified and quick method to the inspection of the working conditions of a suspension system. Therefore, a simple system to determine these parameters is needed. An analysis of the suspension parameters is performed using mathematical modeling and numerical analysis conducted using the Working Model software. The result derived from the developed methodology shows small errors when compared with the generic values, and it can be concluded that the design of the suspension parameter measurement device using the developed methodology is useful, simple, and has sufficient accuracy.  相似文献   
113.
Variations in track temperature, surface conditions and layout have led tyre manufacturers to produce a range of rubber compounds for race events. Each compound has unique friction and durability characteristics. Efficient tyre management over a full race distance is a crucial component of a competitive race strategy. A minimum lap time optimal control calculation and a thermodynamic tyre wear model are used to establish optimal tyre warming and tyre usage strategies. Lap time sensitivities demonstrate that relatively small changes in control strategy can lead to significant reductions in the associated wear metrics. The illustrated methodology shows how vehicle setup parameters can be optimised for minimum tyre usage.  相似文献   
114.
为了满足锻造生产厂厂商对自动化生产设备的要求,锻造设备制造厂厂商开发了预锻、锤锻自动化等新设备,提出了新的设备驱动理念,研制了新一代的控制系统。  相似文献   
115.
More than 10000 different types of ship ply the waters of Bangladesh all year round, but the performance of these ships in terms of CO2 emission is not known an...  相似文献   
116.
在现有感应控制二次过街系统中,道路两边以及安全岛按钮控制多为分开控制,没有相互协调,行人在安全岛等待时间过长易导致违章过街等问题。在一次过街感应控制算法基础上,结合二次过街相关理论、机动车与行人延误机理以及行人过街信号配时理论,提出"人行绿波"协调思路,对路段二次过街感应控制算法进行设计,并应用Vissim软件进行仿真验证,结果显示设计感应控制算法能有效地降低行人和机动车延误。  相似文献   
117.
118.
Environmental risk evaluation criteria   总被引:1,自引:0,他引:1  
This paper describes an approach to incorporating environmental risk evaluation criteria within IMO’s guidelines for Formal Safety Assessment (FSA). Such criteria are currently absent from FSA, and the discussion to include them has just started. Said criteria are relevant for evaluating on a cost-benefit basis Risk Control Options (RCOs) for reducing oil spill pollution risk. Oil pollution may comefrom any ship, including bunker spills from non-tank vessels. RCOs are not necessarily ship-based, and may include vessel traffic management information systems (VTMIS) and other options. The proposed approach may be useful in extending FSA to cover environmental risk evaluation criteria and combines such criteria with criteria already in use in FSA. It can also readily be extended to environmental consequences other than oil pollution. Recent IMO developments on this matter are also reported.  相似文献   
119.
Recent sedimentary study of the shelf of the Basque country   总被引:2,自引:1,他引:1  
The Northern Iberian margin of the Spanish Basque country (provinces of Gipuzkoa and Viscaia) is characterized by a narrow continental platform, which receives inputs of riverine particulate matter from the numerous riverine systems located within the Basque country. This particulate matter is subsequently deposited within the Bay of Biscay, and Gouf de Capbreton [Frouin, R., Fiuza, A.F.G., Ambar, I., Boyd, T.J., 1990. Observations of a poleward surface current off the coasts of Portugal and Spain during winter. Journal of Geophysical Research 95 (C1), 679–691]. The main goal of this study is to establish a map of the surface sediment distribution of the Basque continental shelf and more specifically to map the muddy patch located at the eastern side of that continental shelf.Three oceanographic cruises were conducted in 2003 and 2004. From these campaigns 340 surface samples, 12 short cores and 3 gravity cores have been collected over the mid and outer shelf from depths ranging between 50 m and 150 m deep. 3 seismic profiles were obtained across the shelf mud patch using a Sparker device.Sediment grain-size analyses were performed by the classical physical method of sieving and use of settling columns. The POC (Particular Organic Carbon) amounts in sediment and water samples were determined using the Strickland and Parsons' method [Strickland, J.D.H., Parsons, T.R., 1972. Determination of particulate carbon. In : A practical handbook of seawater analysis. Fisheries ResearchBoard of Canada, Ottawa, pp. 207−211] as adapted by Etcheber [Etcheber, H., 1981. Comparaison des diverses méthodes d'évaluation des teneurs en matières en suspension et en carbone organique particulaire des eaux marines du plateau continental aquitain. Journal de Recherche Océanographique VI (2), 37−42]. Radioisotopic measurements (210Pbexc) were made using a semi-planar germanium detector coupled to a multichannel analyser. Radiographical analysis was performed with an X-ray equipment (SCOPIX®) coupled with a radioscopy instrumentation and processing unit.Firstly, a detailed sedimentological map of this shelf has been produced and secondly, geophysical surveys have precisely mapped the geometry of the main mud patch on the continental shelf. In the mud patch itself the rates of sedimentation are between 0.13 and 0.50 cm yr− 1. The maximum rate of sedimentation is located in the central mud patch, whereas the minimum rate of deposition occurs close to the rocky outcrops. These results seem to be in agreement with the estimation of the total thickness of the mud patch revealed by seismic profiles. The central part corresponds to the maximum thickness of 7 m.Interpretations of the associated oceanic current forcing factors (current direction, wave fetch and wind directional modes) relating to the identified sediment depositional zones are also undertaken.  相似文献   
120.
Optimal liner fleet routeing strategies   总被引:1,自引:0,他引:1  
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