考虑动车接续的高速铁路列车运行线效率评价

将高速铁路动车组接续与列车运行图协同考虑,分析包含动车组折返时间在内的列车运行线占用运输资源及反馈技术指标,给出各子指标的计算方法.以反馈技术指标与占用运输资源的赋权比定义列车运行线效率,考虑列车运行图编制的NP-hard属性,基于DEA方法构建列车运行线效率求解模型.以海南东环线列车运行图为例进行验证,并分析所构建指标的特性.算例中一站直达列车运行线效率非最高,而部分停站时间有效性高的列车运行线效率为全图最高,说明考虑动车折返时间后,运行线相对效率发生了一定变化.直达列车应考虑动车组周转时间合理开行,合理的停站有利于列车运行线效率的提高.

Delays caused by motorized vehicles unable to clear intersections in China: Graphical analysis

In many Chinese cities,motorized vehicles （M-vehicles） move slowly at intersections due to the interference of a large number of non-motorized vehicles （NM-vehicles）.The slow movement makes a part of M-vehicles fail to leave intersections timely after the traffic signal tums red,and thereby conflicts between vehicles from two directions occur.The phenomenon was analyzed graphically by using the cumulative vehicle curve.Delays in three cases were modeled and compared：NM-vehicle priorities and M-vehicle priorities with all-red intervals unable to release all vehicles,and longer all-red intervals ensuring release all vehicles.Marginal delays caused by two illegal behaviors that occasionally happened in mixed traffic intersections were also investigated.It is concluded that increasing the speed of M-vehicles leaving intersections and postponing the entering of NM-vehicles are the keys in mathematics,although they are uneasy in disordered mixed traffic intersections due to a dilemma between efficiency and orders in reality.The results could provide implications for the traffic management in the cities maintaining a large number of M-and NM-vehicles.

Performance optimization of electric power steering based on multi-objective genetic algorithm

The vehicle model of the recirculating ball-type electric power steering (EPS) system for the pure electric bus was built. According to the features of constrained optimization for multi-variable function, a multi-objective genetic algorithm (GA) was designed. Based on the model of system, the quantitative formula of the road feel, sensitivity, and operation stability of the steering were induced. Considering the road feel and sensitivity of steering as optimization objectives, and the operation stability of steering as constraint, the multi-objective GA was proposed and the system parameters were optimized. The simulation results show that the system optimized by multi-objective genetic algorithm has better road feel, steering sensibility and steering stability. The energy of steering road feel after optimization is 1.44 times larger than the one before optimization, and the energy of portability after optimization is 0.4 times larger than the one before optimization. The ground test was conducted in order to verify the feasibility of simulation results, and it is shown that the pure electric bus equipped with the recirculating ball-type EPS system can provide better road feel and better steering portability for the drivers, thus the optimization methods can provide a theoretical basis for the design and optimization of the recirculating ball-type EPS system.

New Suburban Emu Sets in Norway ＆ Their Influences Due to Stresses on the Railway Network

Currently new suburban trains for the operating company Norwegian State Railways are being delivered. The innovative EMU Class BM72 four-unit electric train sets should replace the existing operational EMU Class BM69 three-unit electric train sets which have been in service for more than almost 40 years. Hence, a renewal of the suburban train fleet seemed to be necessary. Due to the design, the new four-unit electric train sets have unusually high axle loads being used as suburban train for passenger traffic. As an average, the EMU Class BM72 train sets have axle loads which are approximately 22-25 percent higher than axle loads of the existing EMU train sets of class BM69. Hence, this paper will discuss the consequences concerning rail stresses and track deterioration tendencies with respect to a total replacement of the BM69 sets to the BM72 sets. Approved hand tool calculation methods found in the literature will be applied in order to calculate the stresses. Further will works completed by the ORE- committee D 161 be applied regarding considerations with respect to track damages. In this case, relative comparisons between EMU Class BM72 and EMU Class BM69 will be carried out.

Development of the Interurban Service with the Use of Alternative Commercial Road Trains

The main task of this paper is to review the principal aspects in organization of interurban long haul service with the use of road trains on the basis of the ＂district＂ traffic system. The goal of the paper is to determine the most effective methods of trucking operations in order to highlight the regularities that characterize these methods. The paper describes practicable methods of freight flow analysis, some factors and parameters concerning movement of motor-vehicle trains and original route schedules as well. Of special interest is the obtained algorithm of economically effective trucking operations of motor-vehicle trains on the route.

Road traffic fatalities among pedestrians, bicyclists and motor vehicle occupants in Sirjan, Kerman, Iran

Objective： To analyze the crash and injury data in forensic medicine for years of 2004-2007. Methods： A sample of over 567 accident cases （9 pedestrians, 116 bicyclists, and 442 motor vehicle occupants） was considered from the Department of Forensic Medicine, Shahid Bahonar University of Kerman, involving drivers of all ages and covering a four-year period. Results： The male fatality rates were significantly higher than female ones. The groups at 15-30 years old and at 30-55 years old had the first and second highest numbers of deaths （40% and 34%, respectively）. There were substantial differences in distribution of injuries in motor vehicle occupants and pedestrians and bicyclists. Among motor vehicle occupants, there were more head injuries, such as skull fracture, brain contusion, subdural haemorrhage, and epidural haemorrhage. Nearly 77% of fatalities occurred during 08：00-22：00 in Sirjan. Internal bleeding was also higher in motor vehicle occupants. Pedestrians and bicyclists also had head injuries frequently. Conclusions： In spite of reduction of road traffic fatalities in Sirjan in 2007, it is still one of the cities with high road traffic fatality in the world. These results underline the importance of preventive strategies in transportation, suggesting that different methods are necessary to reduce fatalities of various traffic participants.