浅谈桥头跳车原因及防治措施

在软土地基上修建的桥梁,桥头跳车现象普遍存在,但影响桥头跳车的因素很多,是个复杂的问题.本文分析桥头跳车的原因,并提出防治桥头跳车的一些措施.     

蓝牙技术在飞行器地面测试中的应用

飞行器在地面测试目前所采用的是有线电缆网,严重制约了飞行器测试的机动性和计算机化。本文提出一种无线脱落插头概念,其可靠性、安全性能够满足飞行器测试的要求。无线脱落插头是微电子、计算机技术与通信技术相结合产品,是蓝牙技术在飞行器测试中的一个新应用。它将促进飞行器测试自动化,有着广泛的应用前景。     

汽车维修分队能力建设评估指标体系构建与分析

详细分析了汽车维修分队能力建设评估指标体系的构建过程,提出了根据汽车维修分队能力建设本身的内涵及外延,依据有关法规,利用系统论建立评估指标的方法,给出了评估指标体系。此指标可用于对汽车维修分队建设的考核,对汽车维修分队建设具有一定参考价值。     

基于现有技术条件下我国电动汽车商业化之路

目前我国电动汽车的发展进入了瓶颈阶段,即无法实现商业化。制约电动汽车商业化的障碍主要有:电池充电时间长,效率低;整车价格贵、汽车整体运行成本高;缺乏足够的充换电网络和专业的维修网点。在现有技术条件下解决电动汽车商业化的有效途径是采取换电模式,其优点为:没有技术障碍问题、换电站投资成本低、缩短车辆的等待时间、提高电池的使用寿命、降低电池的使用成本。目前应由国家制定统一的电池标准和充电设备等标准,并依托中石油、中石化、南方电网等央企来构建充换电网络。     

Severity of alcohol-related motor vehicle crashes in British Columbia: case - control study

The objective of the present study was to compare the injury severity and vehicle damage severity rates of alcohol-related crashes with rates of non-alcohol-related crashes in British Columbia (BC). Injury severity rates and vehicle damage severity rates were taken from 2002 Insurance Corporation of British Columbia traffic collision data. The data were computed in order to compare the differences in injury severity and vehicle damage severity rates of alcohol-related vs. non-alcohol-related motor vehicle crashes. Case - control methods were used in this study to analyse the risk of alcohol-related crashes compared to non-alcohol-related crashes in BC. Odds ratios (OR) and 95% CI were calculated to estimate relative risks. In the case - control analysis, the risk of fatal collision was increased for those drinking and driving compared with those driving sober (OR 4.70; 95% CI 3.15 - 7.01). Risk of injury collision was increased for those drinking and driving compared with those driving sober (OR 1.32; 95% CI 1.19 - 1.37). Importantly, the risk of vehicle damage severity was increased for those drinking and driving compared with those driving sober (write-off vehicle OR 4.24; 95% CI 3.70 - 4.86, severely damaged vehicles OR 1.98; 95% CI 1.77 - 2.21). The study reinforces existing literature to suggest that current evidence is sufficient to show an increased risk of injury and fatality to drivers and occupants in alcohol-related crashes. This paper not only emphasizes this well-known relationship, but also such consequences as increased vehicle damage severity. The connection between drinking and severity of motor vehicle crashes is popularly believed and has now received substantial scientific support. There is strong justification for injury prevention experts and policy-makers to step up motor vehicle crash injury prevention advocacy by implementing evidence-based policies to reduce rates of alcohol-impaired driving in the province of BC. Most unintentional injuries in BC are related to motor vehicle crashes. Significant improvements can be made in these statistics by: increasing the use of occupant protection (safety belt and child restraint seats); reducing alcohol-related injuries through multiple strategies including corrections in the physical environment, extensive enforcement of drinking and driving laws and health promotion/education.     

一种改进的重置成本法在旧机动车价格评价体系中的应用

旧机动车属于固定资产机器设备的一类产品,对旧机动车的评估也是以资产评估理论为基础,评估中重置成本法具有更多的优点和更广阔的适用范围,因此本文选择重置成本法作为旧机动车评估的理论依据.将原有的重置成本法公式进行改进,对成新率的综合调整系数采用了英国运筹学家赛特(T.L.Saaty)提出的层次分析法进行确定.文章详细介绍了这一种改进的重置成本法,并通过实例进行了实际应用.     

联合V2X通信和最小跳数距离的车辆定位方法

针对传统V2X定位方法定位成功率及定位精度较低的问题,提出了一种联合V2X通信和最小跳数距离的车辆定位方法。车辆利用最小跳数距离估算自身与通信范围外辅助节点间的相对距离,并利用路径相似度因子最高的辅助节点对该误差进行补偿,从而改善定位性能受通信距离约束的局限性。同时,综合考虑距离、辅助节点类型对定位性能的影响,利用加权最小二乘法对车辆位置坐标进行解算,提升定位的精度。仿真结果表明,所提定位方法与V2X定位方法相比,在定位成功率及定位精度方面分别提升38.6%和12.5%,具有一定的应用价值。     

The Motor Industry in an Enlarged EU

The motor industry in the ‘First Fifteen’ EU makes an enormous contribution to its economic prosperity. This is manifest in the scale of employment, output, investment, international trade and technological change. The enlargement of the EU will see the full integration of the auto sector in the accession countries with the activities in the West to reinforce its already massive scale. The nature of optimum size and the importance of economies of scale creates a bias to bigness in vehicle manufacture. Hence, the auto industry in the accession countries consists largely of the local operations of transnational companies. As car demand is income elastic the level of sales in the accession countries is relatively small but as the economies expand the potential is enormous. This, together with non‐scaler advantages such as low wage rates, has attracted considerable investment by vehicle firms in the last fifteen years into the accession countries. Various tariff reduction agreements have meant that integration of the East Central European motor industry with Western operations has pre‐dated the current formal enlargement of the EU. The countries that have done particularly well in attracting automotive investment have been Poland, the Czech Republic and, particularly, Slovakia. The recent history of the auto sector in the accession countries has not been without its problems. The collapse of the command economies saw disruption in the market and the decline of the local indigenous car makers. Subsequently this was more than offset by new inward investment. There has been no revival of the local commercial vehicle industry and further restructuring can be expected. The long‐term survival of the auto component sector in the accession countries will depend on how the sector responds to the competitive challenges of free trade and enlargement. However, there are signs that significant high value‐added activities such as vehicle design and development, will be sustainable in East Central Europe. The motor industry in the accession countries will face its own challenges, not least the tendency of the industry to anticipate formal integration. This time it will mean expansion into Eastern Europe. Hence, whilst the location of vehicle plants in the accession countries challenges the traditional centres of manufacture in the West, including ‘the periphery’, in turn they must be alert to even newer competition elsewhere.     

Telematics: Decision Time for Detroit

With implications for navigation, safety, entertainment and vehicle maintenance as well as regulation and infrastructure investment in roads, telematics has the potential to transform driving more than any other innovation for decades. In the already well-established Asian telematics industry, revenue tends to come from extra charges at the time of vehicle-sale, with most subsequent services provided free. The US model has evolved differently, with much of the cost of telematics hardware and software subsidized in the initial vehicle sale price and revenue coming from services used. The decision to invest in telematics is therefore riskier in the US. This article first briefly summarizes the potential of telematics. It then analyzes the investment risks, particularly for automakers. It concludes with recommendations on how the US auto industry can minimize risk and make the most of the opportunities.     

An Analysis of Trade Performance of the Australian Passenger Motor Vehicle Industry: Trends,Patterns, and Determinants

This article presents an empirical analysis of the trends, patterns, and determinants of the Australian passenger motor vehicle industry trade in the context of policy liberalization. Although export orientation and import penetration ratios have shown rising trends, especially since the early 1990s, faster growth in import penetration has led to a surge in the industry’s trade deficit. Econometric results appear to suggest that tariff protection, export incentives, and government assistance have made the industry less competitive, in domestic and world markets. These findings indicate that further liberalization may help improve the Australian passenger motor vehicle industry’s trade performance.     

物流配送管理中车辆路径问题研究

本文论述了物流配送管理中车辆路径问题,研究了车辆路径问题的定义、模型,提出了根据客户、车辆和配送中心三类限制条件来对车辆路径问题进行分类的方法。     

Transiting to Work: The Role of Private Transportation for Low‐Income Households

This study examines the role of reliable vehicles in facilitating employment, using a new data set, the Iowa Transportation and Employment Survey. The empirical results document significantly higher levels of transportation problems and human capital barriers among low‐income households compared to other households and among low‐income nonworking adults compared to their employed counterparts. The multivariate analysis of low‐income households shows that employment and reliable transportation are related. Respondents without access to a reliable vehicle are less likely to be employed; those employed are more likely to have access to a reliable vehicle. Residence in an area adjacent to a metropolitan area has a positive effect on working.     

基于模糊评判的车辆维修保障能力评估研究

分析了影响维修保障能力的因素;运用模糊综合评判的方法建立了车辆维修保障能力评估模型;对该模型进行了实例分析,验证了该算法的合理性和有效性。     

外测系统箭（弹）载电子设备EMC的考虑

阐述了箭（弹）载连续波相参应答机机内由于电磁干扰（ＥＭＩ）而产生锁相环虚假锁定的机理以及消除方法。     

车辆自动识别系统移动站及其在城市交通监管中的应用

车辆自动识别系统 (AVI)移动站具有机动、快速和自动识别车辆的特点 ,适合于在城市监管中广泛应用。它采用射频识别 (RFID)技术 ,通过车卡 (TAG)采集车辆数据信息 ,对车辆进行自动识别和处理 ,识别率超过 99%;采用视频识别 (VFID)技术 ,通过摄像机采集车辆图像信息 ,在光照较强的情况下 ,识别率可以达到 80 %以上。     

Ford Motor Company's Global Electrification Strategy

Ford Motor Company has developed global platforms for its vehicles, including hybrid electric vehicles and forthcoming battery-electric and plug-in hybrids. Providing electrification technologies is a key element of Ford's broader strategy of producing vehicles that have improved fuel economy and reduced greenhouse emissions. The breadth of this effort—across a range of vehicle types—is unique in the automotive industry. Of particular importance is using the same vehicle platforms for electrified vehicles as for conventionally fueled vehicles in Ford's global strategy. Infrastructure development is a key element in the success of plug-in hybrid and battery electric vehicles. To this end, Ford is developing home-charging systems and communication networks that will enable drivers to find recharging stations.     

Speed control in developing countries: issues,challenges and opportunities in reducing road traffic injuries

Speed has been determined to be one of the most common contributing factors in vehicle crashes. This study explores vehicle speed as a factor in the causation of road traffic crashes, using the example of Ghana. It examines the effectiveness of various speed control measures, based on policereported traffic crashes in Ghana and published works on speed control measures in both industrialized and developing countries. In Ghana, pedestrians were the main victims of road traffic injuries. The dominant driver error assigned by traffic police was loss of control, with the underlying factor being excessive vehicle speeds. The ‘speed factor’ alone accounted for more than 50% of all Ghanaian road traffic crashes between 1998 and 2000. While the enforcement of speed limits by traffic police may not be affordable for most developing countries, rumble strips and speed humps were found to be effective on Ghanaian roads. Rumble strips installed on the main Accra-Kumasi highway reduced crashes by about 35% and fatalities by about 55%. Reducing vehicle speeds may be one of the most effective interventions to stem traffic crashes in low-income countries. However, setting lower speed limits is not an effective intervention without the traffic law enforcement resources to ensure that limits are followed. Developing countries must also look to other speed reduction measures such as speed bumps and rumble strips, roads that segregate high- and low-speed users, and technological solutions such as speed governors, as well as greater public awareness of the problem.     

The exchange rate and the price level

The US-Dollar has inflated the world. Its vehicle is the present international monetary system of pegged exchange rates. This system which was introduced to stimulate International trade and division of labour between the different countries became an important promoter of world wide inflation.     

飞行器卫星通信链路设计与分析

介绍了飞行器与卫星间通信链路的组成、工作原理和系统设计考虑,讨论了系统信息传输 体制和飞行器载设备的实现。通过理论计算及仿真,进行了系统关键技术及主要性能指标的 可实现性分析,对工程应用具有一定参考价值。     

自由贸易协定原产地规则调整的经济效应评估——以《美墨加协定》汽车原产地规则为例

本文使用2011—2019年美国汽车市场数据,测度了1354款车型的需求价格弹性和替代弹性,在识别了原产地规则限制度对合规车型售价影响的基础上,反事实模拟测算了《美墨加协定》汽车原产地规则调整的经济效应。研究发现:(1)美国汽车市场上各款车型的需求价格弹性和替代弹性是异质性的;(2)以北美区域价值含量为代理变量的原产地规则与美国汽车市场上合规车型售价呈正向相关关系,与不合规车型售价呈U型关系;(3)《美墨加协定》汽车原产地规则限制度的提升,会对需要调整采购决策以继续合规的车型销量产生负向冲击,其他车型受市场替代效应的影响,其销量有所增加;(4)原产地规则调整降低了对北美自由贸易区外汽车中间品的需求,提升了对区内汽车中间品的需求。