基于应力优化的大客车结构多目标优化

对某全承载式大客车进行了结构有限元分析,研究了该客车结构强度、振动模态频率、质量等多个性能目标的优化设计问题.分析结果表明,该客车初始设计模型的刚度满足设计要求但应力较大.强度储备不足,因此采用优化结构最大应力的方法进行优化.经过两个阶段的优化设计,显著降低了结构最大应力.提高了一阶扭转频率,减轻了车身骨架质量,客车结构设计更为合理.     

基于神经网络的桩基完整性预测分析

反射波法进行桩基完整性检测时,常规理论分析结果与实际状态存在一定的差异。文中以反射波法检测基本数据为基础,分析影响桩基质量的主要因素,针对桩土共同作用的动静力学特征,选择了5个方面的重要因素,建立神经网络评价系统的影响因子,根据这些影响因素对桩基质量检验的影响规律,给出它们的影响系数。通过建立神经网络预测系统,对桩身缺陷的位置、类型和程度给予合理准确的解释。     

Security Mechanisms of Wired Equivalent Privacy and Wi-Fi Protected Access in WLAN： Review and Analysis

An analysis of WLAN security mechanisms of wired equivalent privacy (WEP) and Wi-Fi protected access (WPA) discovers that the current literature is not totally creditable in its judgment on the security value of WEP and WPA.Based on the respective performances of WEP and WPA under certain typical attacks,this paper substantiates the judgment that WEP has quite a few vulnerabilities concerning confidentiality and integrity,but at the same time challenges the judgment on WPA with that WPA is robust enough to confront potential typical attacks and is not so unreliable as the current literature believes,although it has some vulnerabilities in its message integrity code (MIC).     

降低机车车辆电子产品及其系统风险的对策

从硬件和软件可靠性改计、保护、故障诊断和冗余几方面阐述了降低机车车辆电子产品及其最统风险的各种播施及其有效性。在产品设计阶段．就必须考虑各种降低风险的对策,采取行之有效的措施．才能得到高安全完整性的产品。     

在役输气管线的完整性评价方法

引入国外发展较好的完整性评价技术,从影响在役输气管线完整性的各种因素着手,对在役输气管线的完整性评价从安全性、可靠性和风险性3个方面进行分析。管道完整性评价是将3种评价方法有机结合起来,深入研究将大大减少管道事故的发生,并减轻事故造成的后果,从而为在役输气管线的完整性管理提供可靠的依据。     

重载铁路移动闭塞系统架构研究

依托大秦铁路,研究重载铁路移动闭塞系统架构.根据移动闭塞原理,设计重载铁路移动闭塞系统架构.详细介绍系统架构设计要点、重载铁路既有信号系统实现移动闭塞功能需新增的关键技术和设备,以及基于列车位置追踪的移动闭塞安全功能.在重载铁路既有线引入移动闭塞系统,可以提升大秦铁路乃至我国重载铁路货物运输能力.     

在役风险管道检测与评价技术在湖田管线的应用

目前,在役老管道存在防腐层老化、管体腐蚀等问题,急需对在役风险管道进行检测和安全评价。文中以湖田输气站至烯烃厂天然气管线为实例,提出了管道完整性检测技术与安全评价方法,确定管道的现状,并提出相应措施及建议,保障管道安全运行。     

超限超载货物运输系统结构模型分析

对超限超载货物运输形成机理的研究是长效治理超限超载的基础工作。运用系统解释结构模型法（ISM法）,分析了超限超载货物运输影响因素间的层次作用关系．明确了各影响因素在超限超载货物运输形成过程中所发挥的不同作用．指出相关法制建设的滞后与交通规费收取模式的不合理是导致超限超载货物运输的根源．而市场经济利益驱动是其直接诱因．为长效治理超限超载货物运输提供了理论支持。     

公铁两用挖掘机上道作业防倾覆机构设计

公铁两用挖掘机因上道、下道灵活便捷,改装后具备换枕、道床整形等功能得以逐步推广应用.为保障公铁两用挖掘机通过曲线及大臂旋转90°时的作业安全,设计防倾覆机构,依靠勾舌抱紧钢轨轨头外侧下缘的方式平衡倾覆力矩,保持车辆稳定.防倾覆机构采用液压驱动,通过油缸控制勾舌开合,完成挖掘机上道、下道和工作状态转换.运用试验证明,设置...     

Understanding user acceptance factors of electric vehicle smart charging

Smart charging has been the focus of considerable research efforts but so far there is little notion of users’ acceptance of the concept. This work considers potentially influential factors for the acceptance of smart charging from the literature and tests their viability employing a structural equation model, following the partial least squares approach. For a sample of 237 early electric vehicle adopters from Germany our results show that contributing to grid stability and the integration of renewable energy sources are key motivational factors for acceptance of smart charging. In addition, the individual need for flexibility should not be impaired through charging control. Further well known influential factors like economic incentives do not seem to have a significant impact in the sample group under scrutiny. These and further findings should be taken into account by aggregators when designing attractive business models that incentivize the participation of early adopters and ease market rollout.