基于云平台的铁路视频系统及安全技术研究

云技术的广泛应用是信息技术发展的新趋势,铁路视频监控系统无论从存储的可扩展性、安全性还是从集中管理、大数据收集的角度,都需要云技术的有力支撑,云技术的应用也会带来新的安全问题,如云数据安全风险、虚拟化安全风险、非法访问风险等。简要分析铁路视频监控系统面临的安全问题和相应的安全技术方案。     

高桩码头评估的干扰能量法及与常规方法的对比

针对高桩码头的检测评估工作中缺少合理有效的评估方法和评估指标的问题,对结合干扰能量法的高桩码头结构评估指标进行研究。采用变分原理和最小势能原理,结合高桩码头的结构特点,建立基于干扰能量法的高桩码头结构整体安全评价的指标体系,并与现行规范进行对比。结果表明,此方法在评估局部构件的同时,还可定量给出结构的整体安全系数,能够反映不同构件对于整体安全性的贡献。     

BIM技术在清华珠三角公建项目施工中的应用研究

随着科技的进步及项目管理水平的提高,BIM技术应运而生。本文以清华珠三角研究院粤港澳大湾区创新基地项目为依托,从应用目标、应用前准备工作、前期策划管理、技术管理、质量安全管理、物资设备管理、进度管理、经济成本管理等方面开展BIM技术在公建项目施工中的应用研究,结果表明:使用BIM技术,使项目管理走向精细化、全面化、高效化,并提高质量标准,增加安全保障,减少项目成本,提高项目利润率;同时与AI技术相结合,使BIM技术更加具有简便性,产出更大效益。     

道路运输行业安全监管现状分析及对策研究

结合道路运输行业安全监管现状,从道路运输行业安全监管职责和内容、监管方式、安全检查方面对道路运输行业安全监管存在的问题进行分析,并有针对性的提出了相应的建议和对策。     

锂动力电池成组规模及结构形式对绝缘性影响

本文以UUV用锂动力电池组为对象,研究电池模块串、并联关系对成组绝缘性能的影响,结果表明电池成组规模越大,绝缘性能越差。考察了锂电池组不同部位的物理隔离对成组绝缘性的影响,结果表明对电池模块与模块、电池组与UUV舱体间采取绝缘防护,可有效提升电池成组绝缘性能。     

道路环境对交通安全的影响及对策

交通安全,涉及到人、车以及道路和环境等很多因素。近年来,因为各种原因使得有关单位以及人员将更多的将精力放在人、车、道路这几个因素上,对道路交通环境没有过多的考虑和研究。深入研究道路交通环境,有利于道路交通的安全,文章通过对其的研究和分析,得出有关道路交通环境对交通安全的影响和解决措施,对于防止道路交通安全事故具有重要意义。同时为人们的生命财产的安全提供保障、对构建社会主义和谐社会具有很大帮助。     

Analysis of volatility in driving regimes extracted from basic safety messages transmitted between connected vehicles

Driving volatility captures the extent of speed variations when a vehicle is being driven. Extreme longitudinal variations signify hard acceleration or braking. Warnings and alerts given to drivers can reduce such volatility potentially improving safety, energy use, and emissions. This study develops a fundamental understanding of instantaneous driving decisions, needed for hazard anticipation and notification systems, and distinguishes normal from anomalous driving. In this study, driving task is divided into distinct yet unobserved regimes. The research issue is to characterize and quantify these regimes in typical driving cycles and the associated volatility of each regime, explore when the regimes change and the key correlates associated with each regime. Using Basic Safety Message (BSM) data from the Safety Pilot Model Deployment in Ann Arbor, Michigan, two- and three-regime Dynamic Markov switching models are estimated for several trips undertaken on various roadway types. While thousands of instrumented vehicles with vehicle to vehicle (V2V) and vehicle to infrastructure (V2I) communication systems are being tested, nearly 1.4 million records of BSMs, from 184 trips undertaken by 71 instrumented vehicles are analyzed in this study. Then even more detailed analysis of 43 randomly chosen trips (N = 714,340 BSM records) that were undertaken on various roadway types is conducted. The results indicate that acceleration and deceleration are two distinct regimes, and as compared to acceleration, drivers decelerate at higher rates, and braking is significantly more volatile than acceleration. Different correlations of the two regimes with instantaneous driving contexts are explored. With a more generic three-regime model specification, the results reveal high-rate acceleration, high-rate deceleration, and cruise/constant as the three distinct regimes that characterize a typical driving cycle. Moreover, given in a high-rate regime, drivers’ on-average tend to decelerate at a higher rate than their rate of acceleration. Importantly, compared to cruise/constant regime, drivers’ instantaneous driving decisions are more volatile both in “high-rate” acceleration as well as “high-rate” deceleration regime. The study contributes to analyzing volatility in short-term driving decisions, and how changes in driving regimes can be mapped to a combination of local traffic states surrounding the vehicle.     

In search of surrogate safety indicators for vulnerable road users: a review of surrogate safety indicators

Surrogate indicators are meant to be alternatives or complements of safety analyses based on accident records. These indicators are used to study critical traffic events that occur more frequently, making such incidents easier to analyse. This article provides an overview of existing surrogate indicators and specifically focuses on their merit for the analyses of vulnerable road users and the extent to which they have been validated by previous research. Each indicator is evaluated based on its ability to consider the collision risk, which can be further divided into the initial conditions of an event, the magnitude of any evasive action and the injury risk in any traffic event. The results show that various indicators and their combinations can reflect different aspects of any traffic event. However, no existing indicator seems to capture all aspects. Various studies have also focused on the validity of different indicators. However, due to the use of diverse approaches to validation, the large difference in how many locations were investigated and variations in the duration of observation at each location, it is difficult to compare and discuss the validity of the different surrogate safety indicators. Since no current indicator can properly reflect all the important aspects underlined in this article, the authors suggest that the choice of a suitable indicator in future surrogate safety studies should be made with considerations of the context-dependent suitability of the respective indicator.     

逐日路径演化中出行者信息偏好的实验分析

在逐日出行过程中,出行者对各类信息的偏好是一个动态变化的过程,不同出行者对同类信息的偏好也不同.本研究搭建不同信息条件下逐日路径选择实验场景,用信息偏好系数表征不同类别信息对出行者感知时间影响的相对权重,研究出行者信息偏好的演化规律与分布特征.实验结果表明,出行个体信息偏好的演化存在3种类型,出行群体对感知时间的信息偏好系数先震荡增加后逐步稳定,出行个体对感知时间的信息偏好系数在出行群体中成正态分布.与只提供完全历史信息相比,同时提供基于指数平滑法的系统预测信息会降低出行者对感知时间的偏好.     

Predictive power of inspection outcomes for future shipping accidents – an empirical appraisal with special attention for human factor aspects

This paper investigates whether deficiencies detected during port state control (PSC) inspections have predictive power for future accident risk, in addition to other vessel-specific risk factors like ship type, age, size, flag, and owner. The empirical analysis links accidents to past inspection outcomes and is based on data from all around the globe of PSC regimes using harmonized deficiency codes. These codes are aggregated into eight groups related to human factor aspects like crew qualifications, working and living conditions, and fatigue and safety management. This information is integrated by principal components into a single overall deficiency index, which is related to future accident risk by means of logit models. The factor by which accident risk increases for vessels with above average compared to below average deficiency scores is about 6 for total loss, 2 for very serious, 1.5 for serious, and 1.3 for less-serious accidents. Relations between deficiency scores and accident risk are presented in graphical format. The results may be of interest to PSC authorities for targeting inspection areas, to maritime administrations for improving asset allocation based on prediction scenarios connected with vessel traffic data, and to maritime insurers for refining their premium strategies.