HX_D3B型交流传动电力机车网络控制系统

研究了HXD3B型机车网络控制系统的结构组成和特点,阐述了机车控制单元VCU、牵引控制单元DCU、网关TCN-GW、微机显示单元DDU的功能以及网络控制系统的主要控制功能。     

HX_D3B型交流传动电力机车概述

HXD3B型机车是大连机车车辆有限公司自主开发的六轴大功率交流传动货运电力机车。机车额定功率为9600kW,最高运行速度为120km/h,电传动系统采用IGBT水冷变流机组。文章主要介绍了该型机车的主要特点、主要技术参数、设备布置、通风系统、电气系统、机械系统、制动及供风系统等。     

城市轨道车辆的粘着利用与节能

轮轨间的最佳粘着利用对城市轨道车辆节能起着重要作用.本文分析了城市轨道车辆的粘着特点,提出了改善其粘着利用的途径,并指出了装设粘控装置能实现最佳粘着利用,收到良好的节能效果.     

绝对不应期电刺激对兔心室肌收缩功能影响的钙反应性

目的　观察绝对不应期电刺激增强兔离体乳头肌收缩作用的钙反应性 ,探讨绝对不应期电刺激增强心肌收缩功能的可能机制。方法　分离兔右心室乳头肌、灌流并给予 1HZ 刺激使其等长收缩 ,于该基础刺激的绝对不应期给予双相方波电流刺激 (称之CCM)。依次灌流不同Ca2 + 浓度 (0 .5、1.5、2 .5、3.5、4 .5、5 .5、6 .5mmol·L- 1 )的K H液 ,观察乳头肌的最大张力 (PT)的变化。结果　①CCM刺激时PT比刺激前增加。②CCM对乳头肌张力的作用存在着Ca2 + 浓度量效反应 ,低Ca2 + 浓度下CCM增加PT的作用最明显 ,随着Ca2 + 浓度的增高而作用减弱。当Ca2 + 浓度进一步增高时 ,PT不再增加。结论　于绝对不应期电刺激能明显增强离体心肌的收缩功能 ,提示其可能机制为细胞外Ca2 + 内流增加 ,细胞 [Ca2 + ]i增高     

城市轻轨车辆转向架方案的选择

本文根据城市轻轨车辆用转向架的运用条件和技术要求,结合我国的技术水平和传统特点,对城市轻轨车辆转向架结构设计中应考虑的问题进行了分析,认为在进行轻轨车辆转向架设计时,应采用空气弹簧、盘形制动,弹性车轮、磨耗形踏面、焊接构架等先进技术.     

To save money or to save time: Intelligent routing design for plug-in hybrid electric vehicle

Electric vehicles (EVs) are promising alternative to conventional vehicles, due to their low fuel cost and low emissions. As a subset of EVs, plug-in hybrid electric vehicles (PHEVs) backup batteries with combustion engines, and thus have a longer traveling range than battery electric vehicles (BEVs). However, the energy cost of a PHEV is higher than a BEV because the gasoline price is higher than the electricity price. Hence, choosing a route with more charging opportunities may result in less fuel cost than the shortest route. Different with the traditional shortest-path and shortest-time routing methods, we propose a new routing choice with the lowest fuel cost for PHEV drivers. Existing algorithms for gasoline vehicles cannot be applied because they never considered the regenerative braking which may result in negative energy consumption on some road segments. Existing algorithms for BEVs are not competent too because PHEVs have two power sources. Thus, even if along the same route, different options of power source will lead to different energy consumption. This paper proposes a cost-optimal algorithm (COA) to deal with the challenges. The proposed algorithm is evaluated using real-world maps and data. The results show that there is a trade-off between traveling cost and time consumed when driving PHEVs. It is also observed that the average detour rate caused by COA is less than 14%. Significantly, the algorithm averagely saves more than 48% energy cost compared to the shortest-time routing.     

Carbon and energy footprints of electric delivery trucks: A hybrid multi-regional input-output life cycle assessment

Due to frequent stop-and-go operation and long idling periods when driving in congested urban areas, the electrification of commercial delivery trucks has become an interesting topic nationwide. In this study, environmental impacts of various alternative delivery trucks including battery electric, diesel, diesel-electric hybrid, and compressed natural gas trucks are analyzed. A novel life cycle assessment method, an environmentally-extended multi-region input-output analysis, is utilized to calculate energy and carbon footprints throughout the supply chain of alternative delivery trucks. The uncertainties due to fuel consumption or other key parameter variations in real life, data ranges are taken into consideration using a Monte Carlo simulation. Furthermore, variations in regional electricity mix greenhouse gas emission are also considered to present a region-specific assessment for each vehicle type. According to the analysis results, although the battery electric delivery trucks have zero tailpipe emission, electric trucks are not expected to have lower environmental impacts compared to other alternatives. On average, the electric trucks have slightly more greenhouse emissions and energy consumption than those of other trucks. The regional analysis also indicates that the percentage of cleaner power sources in the electricity mix plays an important role in the life cycle greenhouse gas emission impacts of electric trucks.     

Development of driving cycles for electric vehicles in the context of the city of Florence

Strong efforts are spent in automotive engineering for the creation of so called Driving Cycles (DCs). Vehicle DC development has been a topic under research over the last thirty years, since it is a key activity both from an authority and from an industrial research point of view. Considering the innovative characteristics of Electric Vehicles (EVs) and their diffusion on certain contexts (e.g. city centers), the demand for tailored cycles arises. A proposal for driving data analysis and synthesis has been developed through the review and the selection of known literature experiences, having as a goal the application on a EVs focused case study. The measurement campaign has been conducted in the city of Florence, which includes limited traffic areas accessible to EVs. A fleet of EVs has been monitored through a non-invasive data logging system. After data acquisition, time-speed data series have been processed for filtering and grouping. The main product of the activity is a set of DCs obtained by pseudo-randomized selection of original data. The similarity of synthetic DCs to acquired data has been verified through the validation of cycle parameters. Finally, the new DCs and a selection of existing ones are compared on the basis of relevant kinematic parameters and expected energy consumption. The method followed for the creation of DCs has been implemented in a software package. It can be used to generate cycles and, under certain boundary conditions, to get a filtered access to the measured data and provide integration within simulation environment.     

超小水线面单体船波浪载荷确定方法探讨

通过分析波浪和船体的相对位置,利用微段载荷求和的方法计算静波浪载荷,提出超小水线面单体船的波浪载荷计算方法,实例计算表明在静水平衡状态的基础上,可以有效地计算其静波浪载荷,为超小水线面单体船的研究提供参考。     

在用轻型汽油车的净化技术和使用状况

介绍了为达到全国即将实施的相当于欧Ⅰ的排放标准 ,对在用轻型汽油车进行改造的几种技术方案 ,为我国大量的在用轻型汽油车如何达到排放法规的要求提供借鉴。