基于模糊神经网络的机动车驾驶教练员职业适宜性研究

提出应用模糊神经网络系统,建构教练员职业适宜性的3个要素(即心理素质、驾驶技能和知识的表达阐述能力)的学习样本,分析"三要素"的8项特征参数指标——场依存性、速度估计能力、交通安全意识、简单反应、选择反应、跟踪能力、行车注意力、表达阐述能力等,使用K-均值法对实验样本进行初始分类,形成标准学习样本,使用该样本对所构建系统进行训练和调试。利用经调试训练后的系统,依据所测教练员的心理、心理参数对其职业适宜性进行评价。试验表明:建立的教练员职业适宜性仿真模型能取得很好的评价效果。     

AHP-SWOT法在道路交通安全改善策略中的应用

针对交通事故的特点,探讨AHP-SWOT方法在道路交通事故评价中的具体应用。SWOT(优势—劣势,机会—威胁)分析法是一种综合考虑系统外部环境和内部条件的各种因素,对其进行系统评价并从中选择最佳策略的方法,但是它缺少定量分析的过程。AHP(层次分析法)具有定性分析和定量分析相结合的优势,采用SWOT和AHP相结合的方法进行评价更加合理和准确。将AHP-SWOT方法应用于道路交通安全评价系统,分析道路交通安全系统所面临的机会和威胁、所处的优势和劣势,可为正确评价道路安全水平、制定合理的道路交通安全改善策略提供理论指导。实例证明该方法可行有效。     

道路交叉口冲突仿真分析

针对基于事故的安全评价在数量、周期、均值、随机性等方面以及基于现场冲突观测识别在主观性、可靠性、成本、指标全面性等方面存在的问题,提出基于冲突仿真的交叉口安全预评价分析方法:研究利用安全间接分析(SSAM)模型分析冲突的基本原理和冲突时间(TTC)、遭遇时间(PET)等分析指标的计算方法;以及利用VISSIM仿真软件进行冲突仿真分析应注意的策略。以邢台市某道路交叉口安全改善方案为例,进行改善前后冲突仿真的比较分析。研究结果表明,改善后在通行效率显著提升的同时,交叉、追尾、车道变换冲突的数量均显著减少,TTC值有所增加,说明改善后安全程度有所提升。笔者提出的方法和案例应用为道路交叉口改善措施的安全预评价提供了一种分析途径和有益借鉴。     

道路交通紧急救援服务点的优化选址

针对道路交通紧急救援对公平性、效率性、事故并发性的多目标决策需求,提出用于道路交通救援点选址的多目标决策模型。该模型通过最小化最大救援时间满足救援公平性;通过最大化一次覆盖的需求量和最小化救援点到需求点总加权时间满足救援效率;通过最大化备份覆盖的需求量满足事故并发与重大事故的救援。针对多目标决策模型,开发基于模拟退火法的优化解法,结合算例分析,能够获得减少最大救援时间、最大化一次覆盖和备份覆盖需求量的多个目标方向上最优解,实现pareto最优化的成功率均在95%以上。实例计算比较表明,笔者提出的模型与算法可以为决策者提供多目标选址方案。     

Air Quality Monitoring and Management in Lisbon

The environmental decision-making process is related with the interpretation of data both in spatial and temporal dimensions. This paper presents a methodology that integrates the time-space framework of air quality data to infer the temporal pattern and spatial variability that could be interpreted for environmental decision purposes. Variograms that accommodate time and space lags were used for the analysis and proved to be effective. Its environmental meaning, in particular its relationship with traffic patterns is discussed. Data from air quality monitoring stations located in the central part of Lisbon were used in this study. It describes a strategy to identify the type of vehicles responsible for certain pollutant levels, particularly for nitrogen oxides, and discusses the application of new air quality European legislation to the city of Lisbon, Portugal.     

"九五"期间乌鲁木齐市交通噪声的控制措施及效果

在分析交通噪声影响因素的基础上,对乌鲁木齐市近十年控制交通噪声污染的措施和效果进行了探讨。     

Migratory crustaceans as biomonitors of metal pollution in their nursery areas. The Lesina lagoon (SE Italy) as a case study

Lichens collected in an unpolluted forest (background) in November 2004, transplanted at 41 sampling sites along the Madina-Tetteh Quarshie road, retrieved in February 2005 and analysed were found to contain higher concentrations of Manganese (Mn), Vanadium (V), lead, Cadmium (Cd), Chromium (Cr) and Nickel (Ni) than in the background area. Observations showed that of all the heavy metals studied, Manganese concentrations were highest at all sampling points with maximum values around a traffic light, an intersection and car fitting/mechanic workshops. Significant correlations were found between Ni and Mn, Mn and Cr and Mn and V. Statistical analysis also revealed a relatively even dispersion of the studied elements on the eastern side of the road than on the western side.     

南京市城市典型道路交通噪声控制措施效果初探

针对南京市典型道路的交通噪声控制措施,分别选取低噪声路面、声屏障、隔声窗3种噪声控制措施进行监测,监测显示低噪声路面对整体声级降噪有限,声屏障对于1kHz倍频带以上的中高频隔声相对较好,真空玻璃隔声窗能对低频噪声有显著改善。     

基于尾涡强度的无人机与民机纵向安全间隔评估研究

为了解决无人机频频入侵机场净空,与民航客机发生危险接近的问题,以碰撞风险为量化指标,对无人机与民机需要保持的纵向安全间隔进行评估研究。分析民机尾涡流场对无人机运行的影响,利用Crow近场涡强度消散理论,得到实际尾迹影响区改进Reich碰撞模板,据此建立CNS/GPS性能环境下的纵向间隔评估模型,通过Matlab进行间隔值求解。研究结果表明:模型可以较为准确地反映民机起飞初始爬升阶段无人机尾随运行时导航性能和尾涡迹对所需最小间隔值的影响,并得到给定安全目标水平的计算结果。     

An evaluation scheme for assessing the effectiveness of intersection movement assist (IMA) on improving traffic safety

Objective: Intersection movement assist (IMA) has been recognized as one of the prominent countermeasures to reduce angle crashes at intersections, which constitute 22% of total crashes in the United States. Utilizing vehicle-based sensors, vehicle-to-vehicle (V2V), and vehicle-to-infrastructure (V2I) communications, IMA offers extended vision to provide early warning for an imminent crash. However, most of IMA-related research implements their methods and strategies only in simulations, test tracks, or driving simulator studies that have quite a few assumptions and limitations and hence the effectiveness evaluations reported may not be transferable or comparable.

Methods: This study seeks to develop a generalized evaluation scheme that can be used not only to assess the effectiveness of IMA on improving traffic safety at intersections but to facilitate comparisons across similar studies. The proposed evaluation scheme utilizes the concepts of traffic conflict in terms of time-to-collision (TTC) as a crash surrogate. This approach avoids the issue of having insufficient crash frequency data for system evaluation. To measure the effectiveness of IMA on reducing traffic conflicts, a relative risk is calculated for comparing the risk of with/without using the IMA. As a proof-of-concept study, this study applied the proposed evaluation scheme and reported the effectiveness of IMA on improving traffic safety in a field operation test (FOT). Seven test scenarios were conducted at 4 intersections, and a total of 40 participants were recruited to use the IMA for 6 months.

Results: It was estimated that IMA users have 26% fewer conflicts with TTC less than 5 s and have 15% fewer conflicts with TTC less than 4 s. However, the results vary across different sites and different definitions of conflicts in terms of TTC.

Conclusions: Overall, IMA is promising to effectively reduce angle crashes related to sight obstruction and has potential to reduce not only crash frequency but crash severity.