北京老旧立交桥“平面立交”新设计

随着北京的城市化快速进展,私家车数量快速增长,堵车已成为这个城市每日不可避免地困扰,首都成了"首堵"。老旧的北京环路桥梁在这个大环境下更加不堪重负,陈旧的设施和道路交通模式已经不能适应当下的情况。本文以刘家窑桥为例,分析老旧立交桥的问题。分析结果表明,不同种类的人群对堵车问题有不同的意见,这使得道路模式之间的矛盾愈发明显。针对此问题,该种新型道路交通模式能明显缓和矛盾,最大限度地改善其交通情况。新的道路交通模式基于平面立交理论,以改进软设施的原则对平面立交(刘家窑桥为例)进行的新的设计。在新模式模型中,刘家窑地区10分钟内的车行量增加2-3倍,十分有效地增加了车辆通行流量,有效地减少了刘家窑地区道路的拥堵几率。     

外加剂对双液浆性能影响的实验研究

在水泥-水玻璃的化学反应机理分析的基础上,对氯化铝溶液及磷酸氢二钠两种不同外加剂对浆液凝固特性的影响进行了对比试验研究。试验包括凝胶时间、结石率、抗压强度及耐久性试验,初步获得了两种外加剂水泥-水玻璃浆液性能的影响规律。     

谈OGFC沥青路面施工工艺与质量控制

结合开级配抗滑磨耗层（OGFC）沥青路面的试验研究课题,在室内目标配比及生产配比设计试验的基础上。通过常澄高速公路试验路的铺筑确定了合理的施工工艺。本文在总结试验路施工工艺的基础上,分析了路面空隙率与渗水系数的关系,并介绍了施工工艺和质量控制方法,为今后OGFC路面的推广应用积累一些经验。     

一种求解线性二层规划的修正Frank-Wolf方法

利用迭代点校正方法，将非线性规划中的Frank—Wolf方法应用于线性二层规划问题，从而提出了一种求解线性二层规划的简单算法，同时给出了算法的收敛性．数值结果表明，给出的算法是可行有效的．     

山区双车道公路交通安全隐患改善技术研究

山区双车道公路事故多发,基于现有规范、标准、指南及工程经验制定安全隐患等级评判标准,并运用效益造价比法对安全处治对策进行评估,建立了效益造价比排序模型,为山区双车道公路安全隐患改善有序推进提供技术依据。     

Impedance-based and circuit-parameter-based battery models for HEV power systems

The relationship between voltage and current inside a battery, or the impedance, plays an important role in the simulation and design of hybrid electric vehicle (HEV) power systems. This paper proposes a new approach employing the Bode plot for evaluation of equivalent circuit parameters for a lithium polymer battery (LiPB) for HEV application. The main concept of the proposed circuit-parameter-based model approach is the application of a transfer function used to process the frequency response of the battery for calculation of accurate circuit parameters. Additionally, the Bode plot is also applied to derive the impedance-based model directly from frequency response measurements for short time simulations and practical use in the HEV. Two methods for battery modeling are proposed and verified experimentally with the voltage-current profile of a conventional HEV using the battery measured in this paper. The results show that the proposed circuit-parameter-based technique provides a satisfactory battery equivalent circuit model.     

汽车发动机活塞环陶瓷涂层工艺及性能研究

从活塞环苛刻的工况出发,研究适合活塞环的表面强化工艺,分析等离子喷涂工艺表面处理的技术特点,探讨喷涂陶瓷涂层活塞环的性能变化     

发动机后置式三桥城市客车典型悬架布置方案研究

论述发动机后置式三桥城市客车的设计思路,着重介绍其典型的随动桥布置方式及悬架结构方案。     

Model-Based Integrated Control of Engine and CVT to Minimize Fuel Use

In this study, a model-based integrated control method for engines and continuous variable transmissions (CVTs) is developed. CVT refers to a type of transmission which allows an engine to be operated independently with respect to the vehicle speed, with the engine torque and CVT gear ratio controlled in an integrated manner. In the proposed integrated control scheme, engine operating points which minimize the rate of instantaneous fuel consumption are calculated, and the engine target torque and target gear ratio are determined in an integrated manner based on the results of the calculations. Unlike the previous map-based control method, the method introduced in this study does not require an engine torque map or a CVT ratio map for tuning, and the engine torque and CVT ratio are controlled to minimize the amount of fuel used while satisfying the level of acceleration demand from the driver. The control scheme is based on the powertrain model, and the CVT response lag and transmission loss are also considered in the integrated control processes. The algorithm is simulated with various driving cycles, with the simulation results showing that the fuel economy performance of the vehicle system is improved with the newly suggested engine-CVT integrated control algorithm.     

基于投影法的路线方案评价与应用

根据路线选线时考虑的主要问题,筛选出影响路线走向的相关因素,构建公路路线评价的指标体系;应用投影法,建立路线方案比选模型.实例应用表明:模型能全面地反映路线方案确定的各种影响因素,且能对路线方案做出客观的评价.