整治“外挂”车辆 营造“公平”环境

必须认清外桂和不规范驻地经营现象存在的危害性,采取切实有效的措施,开展治理外桂工作,营造公平的竞争环境．推动道路运输业健康、有序地发展。     

某输油管道刺漏调查分析

某输油管道在5天之内发生了2次泄漏事故,造成了巨大的经济损失。对两次泄漏事故和抢修过程进行了深入调查,对导致输油管道泄漏的各种原因进行了分析。依据管道刺漏形貌及位置,认为内壁腐蚀导致管道穿孔。对管道铺设轨迹进一步调查,研究结果表明管道两次刺漏位置均发生在低谷位置。认为密度较大的水等腐蚀介质容易在管道低谷位置积聚,其液面位置容易腐蚀。根据调查分析结果,对防止输油管道穿孔提出了建议。     

公路主枢纽站场总体布局方案优选模型及算法

在公路主枢纽站场总体布局中 ,可采用多种方法得出若干个布局方案 ,但方案优选是一件复杂的工作 .笔者利用系统工程的方法建立了方案优选模型 ,并对判断矩阵构成、一致性检验及处理、层次排序针对问题特性提出了算法 ,还给出了应用程序框图及程序特点 .模型及算法对公路主枢纽站场布局规划、初步设计中的方案变更及其相关规划设计项目有应用价值     

AEB制动对碰撞事故中假人运动姿态及损伤程度的影响研究

随着汽车安全性能要求越来越高,自动紧急制动系统(Autonomous Emergency Braking,AEB)等主动安全配置在汽车上应用越来越广泛。本文针对碰撞前车辆AEB功能的启用对汽车被动安全阶段(100%正面碰撞,FRB)假人离位及损伤可能产生的影响进行探索研究。研究结果表明:AEB启动自动紧急制动功能,乘员假人的头部、颈部、胸部、骨盆部位会相对车辆有一定的前倾运动。并且车辆AEB自动紧急制动功能启动的情况下发生100%正面碰撞,驾驶员损伤值的增高均早于碰撞前车辆未配备AEB功能车辆驾驶员的损伤值,且最高损伤值小于碰撞前车辆未配备AEB功能车辆驾驶员的损伤值,对于骨盆部位则影响不大。碰撞前AEB自动紧急制动系统功能的启用会导致假人有一定的前倾离位,但不一定导致碰撞后假人损伤最高值的增大。     

Nature of influence of out‐of‐vehicle time‐related attributes on transit attractiveness: a random parameters logit model analysis

This paper describes the nature of the impacts of walking distances and waiting time on transit use. The relative trade‐offs of walking and transfer components with other transit service attributes are also discussed. A total of 449 completed stated‐preference interviews were collected; with six observations from each respondent, the total number of observations was 2694. This data set was used to estimate the coefficients in different utility functions using a random parameters logit model. The results demonstrated that walking distances to and from transit stops have important and significant nonlinear negative influences on the attractiveness of transit. Transfer waiting time was also shown to have a significant nonlinear negative impact on transit attractiveness. The random parameters logit model had a better model fit than the standard logit model. Some of the findings obtained here are novel, while others are consistent with previous works. These findings have implications for both theory and practice. Copyright © 2014 John Wiley & Sons, Ltd.     

耗损故障的三参数Weibull分布极大似然估计方法

鉴于工程实际中经常遇到的耗损故障零部件检修周期和可靠寿命的确定问题,给出一种针对耗损故障的三参数Weibull分布极大似然估计方法,通过计算对方法的正确性和有效性进行模拟验证,结合实例说明该方法在实际中的应用。     

智能N取M型高可靠安全计算机系统

通过分析指出传统故障-安全系统在电子系统日趋复杂的背景下将遇到故障检测复杂性剧增的问题,为解决系统设计的可持续发展问题,满足用户对可靠性和安全性不断提高的需求,提出一种智能的N取M型高可靠安全计算机系统,并在系统的可靠性、安全性、设计成本、可维护性以及系统容量方面同传统安全系统进行对比分析。性能仿真数据说明新的安全计算平台不仅能够完全满足IEC61508中SIL4等级系统的要求,更重要的是,这一类型的安全计算结构极大地降低了对单器件可靠性及安全性的要求,比传统故障-安全结构在设计和维护成本方面更加具备可持续发展的潜力。     

高速列车车轮非圆化与振动噪声关系跟踪试验研究

选定某型号新运营的高速列车进行长期跟踪试验,研究不同运行时期内,车轮非圆化与振动噪声的发展变化规律及两者间的相互影响关系。研究发现:现有的车轮镟修加工手段,不能完全消除车轮非圆化磨耗的再次形成和发展,镟修后车轮会继承部分或者全部镟修前的非圆化特性;部分初始无高阶非圆化特性的车轮,镟修后至列车再运行一定里程时会出现车轮高阶非圆化特征,同时期的振动噪声频谱会对高阶非圆化阶次所在的频率有所反映。在考虑车轮镟修及车辆固有特性两种因素下,分析了车轮高阶非圆化的可能成因,并提出了缓解车轮高阶非圆化、降低车内振动噪声的方法。     

How to restrain participants opt out in shared parking market? A fair recurrent double auction approach

We propose a fair recurrent double VCG (FRD-VCG) auction mechanism to approach the emerging shared parking management problem. In a given shared parking environment with a parking management platform and a double-side perspective, the proposed mechanism considers how to restrain the potential participants (parking slot demanders and slot suppliers) opt out, which is based on the participants’ priority attributes and are calculated with respect to historic auction records provided by the parking platform. Participants’ fairness bids are then generated combining their priority attributes and their submitted bids (bid price and parking time) with the support of a novel evaluation function, which integrates priority attributes, bid price and parking time into an output value. The parking slot allocation rule and transaction payment rule are further designed to dealing with these issues include winner determination and price setting, respectively. Simulations show advantages of the proposed FRD-VCG mechanism, i.e., comparing with the double VCG (D-VCG) mechanism for the shared parking management problem where priority attributes and evaluation function are not considered, the proposed FRD-VCG mechanism has the potential to persuade participants to remain in the market whilst it improves the market’s retention rate, the parking slot’s utilization rate and the participants’ utilities.     

加筋土筋土界面特性试验研究

通过直剪试验研究路堤填料含水量对筋土界面特性的影响规律。试验结果表明,当填料含水量大于其最佳含水量后,界面破坏时的剪切力随着填料含水量的增加而降低。通过拉拔试验,研究填料种类、填料压实度、加筋材料对筋土界面特性的影响规律,可为加筋土工程的设计和施工提供参考。