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881.
The purpose of this paper is to summarize the European maritime transport policy within the context of maritime politics at large. At the outset the legal framework conditions and supportive instruments for the shipping and port industries are presented. Against the background of recent accidents at sea, such as the sinking of ERIKA and PRESTIGE, the EU legislation on maritime safety is of particular interest as it is both complex and rapid in reaction to environmental needs and political pressure. Finally, the sensible relationship between the EU as a regional organization and the IMO as “the competent international organization” is discussed with a view to reconcile possible rivalry and to suggest a complementary cooperation between the two organizations.  相似文献   
882.
The share of immobile persons, i.e. persons not leaving their homes on a given reporting day, is both a central result and a prime quality indicator of a travel diary survey. The wide range of values for the share of immobiles reported in travel diary and time budget survey literature has motivated this in-depth analysis of the reasons for these disparities. This paper collates available evidence on the share of immobiles in travel diary surveys. The share of these non-travellers (UK), or no-trippers (US), varies greatly between otherwise similar surveys. After analysing both disaggregate and aggregate information, this paper concludes that the share of immobiles should be in the range of 8%–12% for the standard one-day, weekday-only travel diary. The analysis suggests that a substantial share of respondents refuse to participate in a soft way, i.e. by claiming not to have left the house. In its conclusions, the paper sketches new ways to reduce the share of such soft refusers during the interview and to identify them during the analysis.   相似文献   
883.
Modelling the temporal response of travellers to transport policy interventions has rapidly emerged as a major issue in many practical transport planning studies and is recognised to hold particular challenges. The importance of congestion and its variation over the day, together with the emergence of time-dependent road user charging as a policy tool, emphasise the need to understand whether and how travellers will change the timing of their journeys. For practical planning studies, analysts face a major issue of relating temporal changes to other behavioural changes that are likely to result from policy or exogenous changes. In particular, the relative sensitivity of time and mode switching has been difficult to resolve. This paper describes a study undertaken to determine the relative sensitivity of mode and time of day choice to changes in travel times and costs and to investigate whether evidence exists of varying magnitudes of unobservable influences in time of day switching. The study draws on data from three related stated preference studies undertaken over the past decade in the United Kingdom and the Netherlands and uses error components logit models to investigate the patterns of substitution between mode and time of day alternatives. It is concluded that the magnitude of unobserved influences on time switching depends significantly on the magnitudes of the time switches considered. With time periods of the magnitude generally represented in practical modelling, i.e. peak periods of 2–3 hours, time switching is generally more sensitive in these data than mode switching. However, the context of the modelling and the extent to which relevant variables can be measured will strongly influence these results.  相似文献   
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基于驾驶员跟车习惯的报警/避撞算法研究   总被引:2,自引:0,他引:2  
张磊  王建强  李克强  连小珉 《汽车工程》2006,28(4):351-355,375
在驾驶员实车实验的基础上,研究跟车工况中的驾驶员行为特性和习惯,建立驾驶员跟随车距模型,并结合对车辆制动过程的分析,研究分别基于驾驶员制动行为特性和驾驶员跟随车距模型的报警/避撞算法,通过改变算法的参数值,可使算法得到的报警/避撞时机符合不同驾驶员的驾驶习惯。利用实验数据对算法进行离线检验,验证该算法在报警/避撞系统中的适用性。  相似文献   
887.
改进的有限时间最优预瞄横向控制器设计   总被引:1,自引:1,他引:1  
马莹  李克强  高峰  郭磊  连小珉 《汽车工程》2006,28(5):433-438
提出了有限时间最优预瞄横向控制算法,根据高速公路车道保持系统实际控制要求,使用了同时考虑车辆当前偏差、预瞄点偏差和控制变量的有限时间二次型性能指标函数。运用最优跟踪算法并进行预瞄距离内曲率恒定的假设,使得控制器参数可以离线求解,保证了车辆控制的实时性。通过仿真及实车试验验证,该控制算法具有较好的跟踪效果。  相似文献   
888.
新型汽车主动避撞安全距离模型   总被引:7,自引:1,他引:7  
侯德藻  刘刚  高锋  李克强  连小珉 《汽车工程》2005,27(2):186-190,199
针对现有模型的不足,以驾驶员车间距保持目的假设为基础建立了一种新型汽车主动避撞安全距离模型,通过驾驶员试验获得了反映驾驶员驾驶特点的模型参数。经仿真及试验对比,该模型计算结果体现了驾驶员的驾驶特点,能够适用于多种交通状况,满足了汽车主动避撞系统的要求。  相似文献   
889.
基于车载微机的混合动力汽车监测与诊断系统研究   总被引:5,自引:1,他引:5  
以某混合动力轿车为研究对象,开展了基于车载微机的混合动力汽车监测与诊断系统的研究,在介绍了该系统用途以及相对于传统的基于CAN总线的监测系统优点的基础上,对系统的硬件设计、软件设计和系统功能进行了详细阐述,并利用仿真网络环境埘系统进行了测试,最终将其应用于某混合动力汽车上.  相似文献   
890.
Over the last twenty to thirty years, railway vehicle dynamics has changed from being an essentially mechanical engineering discipline to one that is increasingly starting to include sensors, electronics and computer processing. This paper surveys the application of these technologies to suspensions and running gear, focused upon the complementary issues of control (which has been reviewed within Vehicle System Dynamics previously) and monitoring (which has not previously been reviewed). The theory, concepts and implementation status are assessed in each case, from which the paper identifies the key trends and concludes with a forward look at what is likely to develop over the next years.  相似文献   
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