在线GSM-R电磁环境测试研究

常规的电磁环境测试方案,不但要求关闭铁路本线所有相关基站,还要求同时关闭临近铁路线路的相关基站,这对于长大线路和日趋密集的GSM-R跨线地区进行电磁环境测试难度更大。因此,迫切需要研究GSM-R在线工作条件下,具备简单可重复性的电磁环境测试解决方案。     

《汽车发动机构造与维修》在线开放课程建设研究与实践

随着课程改革的不断发展,我们更加注重专业教学效果的提升,尤其当前汽修专业的发展,要使学生对汽车发动机构造与维修进行了解,将新技术应用到汽车的维修过程中,明确汽车发动机构造的复杂化,培养技能型新人才,适应当前时代的挑战。所以,对《汽车发动机构造与维修》课程进行有效的改革,满足当前企业人才需求的变化,从课程体系、教学内容、教学方法等方面来进行实际探究,促进整体教学质量和效率的提升,优化课程教学模式。     

网约车安全预警机制探析

针对我国网鈞车平台在安全预警机制方面存在的漏洞以及网约车安全预警机制建立的必要性,提出建立网约车安全预警机制;基于交通运输部介入安全预警机制的目标,实现警企联合,建立快速预警和防范播报机制,提出网约车安全预警机制的全面规划管理,做到合理维护乘客、驾驶人、平台三方的权益,保障公民的人身财产妥全,将危险损害程度最小化以求避免危险事故的发生,同时助力网约车行业健康发展。     

Distributed coordinated in-vehicle online routing using mixed-strategy congestion game

This study proposes a coordinated online in-vehicle routing mechanism for smart vehicles with real-time information exchange and portable computation capabilities. The proposed coordinated routing mechanism incorporates a discrete choice model to account for drivers’ behavior, and is implemented by a simultaneously-updating distributed algorithm. This study shows the existence of an equilibrium coordinated routing decision for the mixed-strategy routing game and the convergence of the distributed algorithm to the equilibrium routing decision, assuming individual smart vehicles are selfish players seeking to minimize their own travel time. Numerical experiments conducted based on Sioux Falls city network indicate that the proposed distributed algorithm converges quickly under different smart vehicle penetrations, thus it possesses a great potential for online applications. Moreover, the proposed coordinated routing mechanism outperforms traditional independent selfish-routing mechanism; it reduces travel time for both overall system and individual vehicles, which represents the core idea of Intelligent Transportation Systems (ITS).     

基于在线振动响应的桥梁损伤识别方法

选用桥梁单元的刚度下降率作为损伤因子.基于铁路列车-桥梁耦合振动模型,计算桥梁在线振动响应对损伤因子的灵敏度并构建灵敏度矩阵,以结构不同状态下的响应残差为约束条件建立灵敏度方程,用Tikhonov正则化方法求解灵敏度方程得到各单元的损伤因子,实现对桥梁损伤的定位和定量评估.应用该识别方法对简支梁桥和2跨连续梁桥的识别结果表明:该识别方法对测点位置不敏感.可根据梁上任意1个测点的响应准确确定损伤位置及损伤程度;不但能识别桥梁的绝对损伤,而且能识别桥梁的损伤增量,即相对损伤;抗噪能力较强,即使噪声水平达到10%,也能正确识别出5%以上的损伤,但对5%以下小幅损伤可能会有误判.     

在线测量不确定度评估及质量控制应用

在线测量是质量控制的重要手段,但实际过程中对于测量误差的忽视容易导致误判和漏判,因此需要采用可靠的方法评估测量误差对过程质量控制的影响.以某发动机工厂在线测量的曲轴线终检机为例,通过研究测量系统的结构和测量原理,分析测量误差的构成和分量,建立测量误差数学模型,评估曲轴终检机的测量不确定度.阐述考虑测量不确定度条件下的质...     

语义网发展对大学生网络思想政治教育的挑战与对策

文章在分析大学生网络思想政治教育背景的基础上,研究了网络发展与大学生网络思想政治教育工作之间的联系,论述了以语义网为代表的Web 3.0带给思想政治教育工作者新的挑战,并针对如何应对新技术提出了一些对策,以期有助于推动新技术在网络思想政治教育工作中的应用。     

接触网承力索的覆冰厚度在线监测技术研究

接触网覆冰会严重影响列车运行安全,为了及时开展防融冰工作,提出一种高效快捷的基于在线监测的覆冰状态分析方法,实时分析接触网的覆冰状态。分析覆冰形成的气象条件以及接触网覆冰的物理模型;利用Ansys软件仿真分析覆冰对接触网补偿装置补偿位移b值的影响,得出覆冰厚度简单近似计算公式,并通过试验验证其准确性;设计覆冰状态在线监测系统,并将系统投入使用。研究结果表明:当达到一定的环境条件时,接触网会发生覆冰,且接触线与承力索的覆冰形态不同;随着覆冰厚度的增加,接触网补偿装置的补偿位移不断增大,根据承力索补偿位移可以较为准确地计算覆冰厚度;经过一段时间的应用,覆冰在线监测系统可以长期稳定运行。     

Evaluating the environmental impacts of online shopping: A behavioral and transportation approach

Various fields and commercial sectors have witnessed a transformation with the advent of the internet. In the last decade, the retail sector in particular has witnessed the massive growth of e-commerce. This has also significantly altered our shopping experiences, influencing a range of decisions, from where, how, and how much to shop. With the consistent growth of e-commerce transactions, more trucks than ever before are entering cities today, bringing with them the negative externalities of increased congestion and pollution. This study first unravels underlying shopping behaviors–both in-store and online–using the 2016 American Time Use Survey (ATUS) data. The authors also develop an econometric behavioral model to understand the factors that affect shopping decisions. At a macro level, the disaggregate individual shopping behaviors are studied by implementing the model to synthetic populations to estimate potential vehicle miles traveled and environmental emissions in two metropolitan areas, Dallas and San Francisco (SF). Finally, the study estimates the impacts of rush deliveries, basket size, and consolidation levels by developing a breakeven analysis between in-store and online shopping. These results confirm the importance of managing the urban freight system, including delivery services and operations, to foster a more sustainable urban environment.     

基于智能运维系统的地铁信号设备维护管理研究

针对上海地铁"故障修+计划修"的信号设备维护管理现状,结合智能化、信息化、专业化的维护管理需求,并基于智能运维系统应用,从维护作业管理及维护流程管理层面,提出信号设备维护管理建议。