驾驶员统计特性对人—车闭环系统响应的影响与汽车主动安全性评价

基于预瞄跟随理论，本文应用一般随机摄动法，对考虑驾驶员不确定性的人－车闭环系统进行响应分析，结合实例，说明该方法在汽车主动安全性评价中的应用。     

净化消声器压力损失计算方法

本文综合运用流体力学、热力学及化学有关理论,对柴油机用的净化消声器的压力损失算法进行推导及试验验证,为在净化消声器设计阶段预测净化消声器对发动机性能的影响提供了可用的手段。     

开目CAPP在武船机制的应用

武昌造船厂机械制造分厂(简称武船机制)是武昌造船厂的下属核心企业,主要进行武船配套零部件的工艺设计与制造。在推进信息化建设过程中,采用了开目CAPP解决方案,取得了较好的效果。武船机制工艺信息化系统需求分析1.产品和工艺特点分析(1)产品的质量要求高,工期要求严格,对工艺设计质量和效率有很高的要求。(2)采用按订单生产的方式,进行独立的成本核算和控制。(3)需从总厂ERP系统中提取工程任务树,建立工艺设计与制造任务。设计完成的工艺数据也需按照ERP系统要求的格式进行统计并向ERP系统进行传递。(4)不同订单中的工艺专业种类繁…     

ISS-based robust adaptive fuzzy algorithm for maintaining a ship's track

This paper focuses on the problem of linear track keeping for marine surface vessels. The influence exerted by sea currents on the kinematic equation of ships is considered first. The input-to-state stability(ISS) theory used to verify the system is input-to-state stable. Combining the Nussbaum gain with backstepping techniques,a robust adaptive fuzzy algorithm is presented by employing fuzzy systems as an approximator for unknown nonlinearities in the system. It is proved that the proposed algorithm that guarantees all signals in the closed-loop system are ultimately bounded. Consequently,a ship's linear track-keeping control can be implemented. Simulation results using Dalian Maritime University's ocean-going training ship 'YULONG' are presented to validate the effectiveness of the proposed algorithm.     

Phase change analysis of an underwater glider propelled by the ocean's thermal energy

The phase change characteristic of the power source of an underwater glider propelled by the ocean's thermal energy is the key factor in glider attitude control. A numerical model has been established based on the enthalpy method to analyze the phase change heat transfer process under convective boundary conditions. Phase change is not an isothermal process,but one that occurs at a range of temperature. The total melting time of the material is very sensitive to the surrounding temperature. When the temperature of the surroundings decreases 8 degrees,the total melting time increases 1.8 times. But variations in surrounding temperature have little effect on the initial temperature of phase change,and the slope of the temperature time history curve remains the same. However,the temperature at which phase change is completed decreases significantly. Our research shows that the phase change process is also affected by container size,boundary conditions,and the power source's cross sectional area. Materials stored in 3 cylindrical containers with a diameter of 38mm needed the shortest phase change time. Our conclusions should be helpful in effective design of underwater glider power systems.     

城市道路交通系统频谱分析方法及应用

对实际道路交通系统特征的研究是通过分析布设在路网中不同地点大量交通信息采集设备采集的数据来进行的。交通信息采集是对城市道路交通系统在时间和空闻上一个采样过程,其数据具有时问和空间属性．本文系统地建立了一种城市道路交通系统频谱分析方法。对于时间采样,通过功率谱分析认为：不同的数据采样间隔,获得的交通信息不同,从而分析出的...     

基于GIS/GPS的高速公路车辆追尾预警系统研究

分析了高速公路车辆追尾事故的原因,研究了车辆安全制动距离,综合驾驶员跟驰与车辆制动模型得到安全距离函数,提出一种基于GIS/GPS的高速公路车辆追尾预警系统框架,建立了车辆报警流程图。该系统有利于预防追尾事故,提高高速公路安全。     

天舟COMAN设计／仿真集成管理系统与PDM、SDM系统的关系

引言 2009年2月27日至3月1日,由北京天舟上元信息技术有限公司主办,《数字军工》杂志社协办的"复杂产品研发核心能力平台建设技术研讨会"在海南三亚成功召开.     

《地铁设计规范》问与答(21)

问题57 《地铁设计规范》第6.2.1条规定:"正线及辅助线钢轨应依据近、远期客流量,并经技术经济综合比较确定,宜采用 60kg/m钢轨,也可采用 50kg/m钢轨."