交通事故黑点鉴别方法研究综述

交通事故黑点的鉴别与改善历来是交通管理实践者与学者所关注的重要研究对象。改善黑点的致灾因素,可以显著的改变道路交通安全管理形势。首先对黑点的定义进行讨论,然后分析了几种常见的确定交通事故黑点的理论方法的优缺点,最后指出了黑点鉴别方法的研究的新趋势。     

道路事故多发路段动力学仿真识别系统

为了从车-路耦合角度客观、直接地识别道路事故多发路段,开发了事故多发路段动力学仿真识别系统,建立了车辆模型、道路模型与车-路耦合模型,提出了事故多发路段识别方法,通过小附着系数路面动力学仿真试验和弯道制动动力学仿真试验进行验证。采用闭环控制方法控制汽车的运行状态,依据道路的特性,选择表征车辆行驶安全性的特征参数,通过特征参数曲线识别事故多发路段。仿真结果表明:在主要考虑道路因素导致事故多发时,所识别出的事故多发路段与依据交警部门事故统计信息所识别出的事故多发路段一致,因此,此系统可行。     

VMS Release of Traffic Guide Information in Beijing Olympics

During the Beijing Olympics, the traffic guidance by VMS achieved excellent effects. The road condition dynamic and quantitative information which was released during the Olympics provided travelers with real-time road conditions and travel time of main Olympic lines. The paper mainly discussed VMS traffic information release based on traffic flow real-time detecting. It introduced the logical structure of the Olympic traffic guidance VMS information release. It posed the data process of VMS release based on the original data collected and discussed certain methods of data process. It also discussed the self-generation model of VMS traffic guidance information. The mid point-centered method and section-centered method were utilized to calculate the travel time and the average speed. Finally, the paper presented the practical effects of the model and algorithm used in the traffic guidance VMS release.     

统计能量法预测铁路声屏障的降噪效果

用统计能量分析（简称SEA）来预测铁路声屏障的降噪效果,并针对某一有声屏障的铁路段进行了SEA模。模型包含列车车体与声屏障之间的声空间以及声屏障2个子结构。计算结果与常用的经验计算方法的预测结果相近。     

滨海港建港条件分析

分析了在废黄河口地区建设滨海港的有利与不利因素,提出了与当地自然环境相适应的“挖入”式总体布置模式。     

统计技术中控制图的应用

详细介绍了控制图的应用方法 ,结合桥梁工程说明如何应用控制图来监控施工过程 ,及时发现问题 ,以保证施工质量     

NINE-YEAR EFFICACY OF HEPATITIS B VACCINATION WITHLOW-DOSE IN THE THIRD INJECTION

Nowthescheduleofvaccinationagainsthep-atitis BisusuallythreedosesoflOUg(or2oUg)',,.Itisusedasgoldstandard,asitislargelyappliedandrecommendedbyvaccinemanufactqrers.Inor-dertousethevaccinemorerationallyandtoobtainsafeimmunizationwithreducedcosts,manystud-iescompareddifferentscheduleswithvariantdosages.Buttheconclusionsdidn'tmatchwitheachother-Andfornolong-termfollowingup,theresultscan'tbeputintopractice.Inadouble-blindandrandomizedtrial,start-edinl986,weprovidedvaccineofvariantdosagesinthethir…     

LONG-TERM EFFICACY AND IMMUNOLOGICAL MEMORY OF PLASMA-DERIVED HEPATITIS B VACCINE 11 YEARS AFTER INITIAL INOCULATION

The length of protection of hepatitis B vaccineand the effective time for vaccine booster doseshave not been defined.Most of studies suggestedthatthe vaccine was effective for8to1 0 years[1～ 5] .However,in most cases,the study design was notrigorous. Many were cross- sectional studies per-formed before and aftervaccination,orstudies thatcompared the vaccinees with the general popula-tion.A few of studies as by Hadler[1] et al .werebased on randomized,double- blind and placebo-controlled tria…     

燃料电池客车氢系统碰撞安全性仿真分析与评价

针对燃料电池客车供氢系统碰撞安全性问题,建立了供氢系统正面碰撞有限元仿真模型,分析了某燃料电池客车氢系统的强度与刚度特性,结果表明,仿真与碰撞试验结果良好一致;该燃料电池客车氢系统的碰撞安全性满足相关法规的要求。     

Research on maximum power point tracking in redundant load mode for photovoltaic system

In order to ensure that the photovoltaic (PV) array always works at the global maximum point of power to increase the system’s overall efficiency, this paper leads the study on maximum power point tracking (MPPT) in redundant load mode. A new control system is designed by combining the redundant electronic load module, embedded controller, supportive capacitor and boost circuit. The system adjusts duty ratio of boost circuit dynamically based on the maximum power point parameter provided by redundant load unit in order to realize MPPT. An experiment shows that no matter whether system is under an even illumination or partly perturbed by shadow, this method can find the exact maximum power point.