长波长轨道不平顺检测中的数字滤波方法

分析和比较了目前较为成熟的轨道长波长不平顺的检测方法，尽管随检测原理的不同，各国的轨检系统采用的处理方法相关很大，但其共同点是均离不开数字信号处理方法，从而保证系统有良好的幅频特性和相频特性。     

轿车侧面碰撞安全性能改进措施探讨

介绍了通过改进车身结构来改善轿车侧面碰撞安全性能的措施:车身侧面结构采用高强度钢、采用填充技术和结构优化技术,并对某车型结构改进实例进行仿真分析,验证了上述结构改进措施的有效性。     

天然气发动机电子节气门控制系统的研究

介绍基于电控调压器的增压单燃料CNG发动机的系统组成,在分析电子节气门结构和驱动原理的基础上,开发了以MC68376为主芯片的电子节气门控制系统,采用TLE6209设计了电子节气门驱动电路。设计了基于模糊自整定参数PID控制器,通过电子节气门在CNG发动机试验台架上的阶跃响应试验和油门开度与节气门开度的跟踪响应试验,验证了所设计的节气门控制系统可以实现对电子节气门精确、快速和稳态误差小的闭环控制。     

大源渡二线船闸人字门静动力数值计算

针对大源渡二线船闸下闸首人字门背拉杆施加预应力与振动问题,进行三维有限元静、动力计算,给出优化模型的多组解,得到背拉杆最优预应力值,同时得到闸门自振频率。分析结果表明,各结构应力均小于材料允许值,门体的斜接柱下角点横向、竖向变形及门轴柱中点横向变形满足要求,为解决船闸人字门背拉杆预应力施工及运行过程中经常产生的人字门振动问题提供了技术支持。     

触觉传感器及感知技术研究现状与发展趋势

触觉感知技术可用于对物体的探索和操作,对环境的交互作用具有重要意义。本文从介绍触觉传感器应满足的机械手操作任务要求出发,全面综述了不同类型触觉传感器的结构和工作原理,并分析了它们的优缺点。分析讨论触觉传感器在人工皮肤和生物医学领域的应用现状,最后总结了先进的机器学习算法和信号处理技术在触觉传感系统中的应用。     

核电站取水口海生物驱赶消杀技术研究

近年来,国内多座滨海核电站海生物频繁入侵,可能引发冷源取水口堵塞、核电站跳堆事故,严重影响核电站的安全可靠运行。本文对国内外核电站冷源防护技术进行了广泛调研,介绍了多种海生物驱赶消杀技术,分析了各种技术的作用原理,论述了各种技术的优缺点,给出了工程指导建议。结合核电站取水口立体纵深防护原则,提出了一种海生物驱赶消杀综合系统模型,为核电站改造以及新建核电站规划设计提供了参考。     

农村客车市场分析

通过对近三年农村客车销售数据的分析,得出农村客车市场低迷的结论;从客运市场、政府政策、市场环境、微观运营等角度分析市场低迷的原因;从长远角度分析农村客车市场,提出农村客车市场发展建议。     

Investigation into untripped rollover of light vehicles in the modified fishhook and the sine maneuvers. Part I: Vehicle modelling, roll and yaw instability

Vehicle rollovers may occur under steering-only maneuvers because of roll or yaw instability. In this paper, the modified fishhook and the sine maneuvers are used to investigate a vehicle's rollover resistance capability through simulation. A 9-degrees of freedom (DOF) vehicle model is first developed for the investigation. The vehicle model includes the roll, yaw, pitch, and bounce modes and passive independent suspensions. It is verified with the existing 3-DOF roll-yaw model. A rollover critical factor (RCF) quantifying a vehicle's rollover resistance capability is then constructed based on the static stability factor (SSF) and taking into account the influence of other key dynamic factors.

Simulation results show that the vehicle with certain parameters will rollover during the fishhook maneuver because of roll instability; however, the vehicle with increased suspension stiffness, which does not rollover during the fishhook maneuver, may exceed its rollover resistance limit because of yaw instability during the sine maneuver. Typically, rollover in the sine maneuver happens after several cycles.

It has been found that the proposed RCF well quantifies the rollover resistance capability of a vehicle for the two specified maneuvers. In general, the larger the RCF, the more kinetically stable is a vehicle. A vehicle becomes unstable when its RCF is less than zero. Detailed discussion on the effects of key vehicle system parameters and drive conditions on the RCF in the fishhook and the sine maneuver is presented in Part II of this study.     

Hierarchical distributed coordination strategy of connected and automated vehicles at multiple intersections

In this paper, we present a hierarchical distributed coordination strategy for connected and automated vehicles (CAVs) that are travelling through multiple unsignalized intersections. The control strategy focuses on the improvement of vehicle fuel efficiency and system mobility. In presence of wireless communication among the involved CAVs and the intersection controllers, our coordination strategy focuses on leading the CAVs travel through a road network without conventional traffic light control and ensuring collision avoidance at the intersection areas. We propose a three-layered coordination strategy in this paper. First, we evaluate the road desired average velocity considering both upstream and downstream traffic to speed up the traffic density balance. Second, the intersection controllers optimally assign reference velocity to each vehicle based on the minimization of velocity deviation from its current velocity and collision avoidance at the intersections. Finally, fast model predictive control (F-MPC) is applied for each vehicle to track their reference velocity in a computationally efficient manner. Two simulation scenarios with different difficulty levels have been implemented on a two-interconnected intersection network. Simulation results indicate the feasibility and scalability of the proposed method, as well as vehicle fuel efficiency and system mobility improvement.     

非线性缆索单元及其在缆索承重桥中的应用

柔性缆索本身所具有的高度几何非线性给缆索计算带来困难,而缆索线形的确定是缆索承重桥能否实现的关键.文中建立了Lagrange坐标系下缆索曲线方程,推导出2节点非线性缆索单元的切线刚度矩阵,并给出了应用该单元求解缆索线形的迭代格式.用该方法计算某大桥方案主缆线形和无应力长度,并将结果与解析法结果对比分析,二者相对误差不大于0.06%,从而证明该方法的可靠性.