电动轮自卸车事故分析与监控系统研究

电动轮自卸车是集发动机、发电机、电动机、液压系统、电控系统于一体的大型运输车辆,发生安全事故会造成重大损失。笔者对造成事故的人为因素和设备因素进行了研究,并用故障树对电动轮起火事故作了较详细的分析,确定了造成事故的重要因素。在此基础上设计了基于CAN总线的安全监控系统。该系统以单片计算机为核心,采用模块化结构,组成控制器局域网络,进行分布式控制。监控系统由硬件系统和软件系统两部分构成。对发电机、电动机、发动机进行技术状态监测的同时监测驾驶员的疲劳状态和违章操作情况,可以减少由人为因素和设备因素造成的安全生产事故。对大型工矿设备的安全技术保障有一定的借鉴作用。     

数控机床的故障诊断

针对数控机床的故障特点，主要介绍了数控机床机械类故障和电气类故障的诊断程序和诊断方法。     

汽车轮胎气压监测系统发展综述

轮胎气压监测系统是汽车上一种新的主动安全技术产品,近年来,在国内外发展迅速。由于它能够实时监测汽车轮胎的气压和温度情况,并能及时给驾驶员以警告,因而可以最大限度地避免由爆胎引发的交通事故,提高了汽车的行车安全。综述了汽车轮胎气压监测系统的发展,包括间接式轮胎气压监测系统、直接式轮胎气压监测系统和下一代无电池轮胎气压监测系统(被动式TPMS)。介绍了各种汽车轮胎气压监测系统的结构组成和工作原理,分析比较了它们各自的优缺点。重点介绍了国外3种主流的直接式TPMS开发系统,对TPMS的研究、开发具有实用参考意义。展望了未来轮胎气压监测技术的发展趋势:无电池TPMS将取代现有类型,成为未来TPMS发展的主流。     

铁路行车安全与司机生理和心理素质关系的研究

从确保铁路行车安全的角度，结合铁路机车乘务工作的职业特点和要求，分析了影响铁路行车安全的诸多因素中最为重要的人的因素在安全驾驶中的作用，以及作为能够胜任我国铁路机车驾驶工作要求的合格司机应具备的生理、心理因素；论文采用国际先进的分析技术和分析软件（ＳＡＳ），对抽取的１２７８ 名现役铁路司机的８８ 个测试因子数据进行了全面综合的统计分析，得出有关司机的心理和生理特征以及与行车安全的内在关系，为提高铁路司机的整体素质及铁路行车安全可靠性提供了科学的依据     

Experimental Study on the Potential Application of Cottonseed Oil–Diesel Blends as Fuels for Automotive Diesel Engines

This paper presents the results of an experimental study on the direct application of cottonseed oil–diesel blends as fuel for diesel engine vehicles without using additional retrofit mechanical systems. The use of biofuels is one of the main actions promoted by the European Union and member states in an effort to tackle global warming, enhance energy security and contribute to regional development. Here, the possibility to blend cottonseed oil directly with fossil diesel as a fuel for diesel engines is examined. This option has lower cost and larger well-to-wheel greenhouse gas benefits than fatty acid methylesters. The paper presents measurements of important fuel properties, density, viscosity, cetane number and cold flow characteristics. In addition, a common rail Euro 3 compliant diesel car is tested using 10% v/v cottonseed oil–diesel blends in order to examine the effects on performance and emissions of regulated pollutants and CO₂. Furthermore, particle emission characteristics are studied, including total and solid particle number concentrations and particle size distributions over driving cycles and steady state modes. The results indicate that the test fuel presents good operating characteristics and limited effects on regulated emissions and vehicle performance. These results would justify further research on the direct use of vegetable oils as automotive fuels.     

柴油汽车掺烧LPG降低黑烟排放技术

研究了柴油机掺烧液化石油气(LPG)以降低黑烟排放的技术方案，并开发出了一种以独特型板调节装置为特征的机械控制式柴油/LPG双燃料供给系统。发动机不改变原有结构加装该系统后即成为柴油/LPG双燃料发动机，可以同时燃烧柴油和LPG两种燃料，并且在整个工作范围内，随着工况变化能够按照预先优化设定的型板型线规律而自动调节柴油／LPG供给量比例，使烟度降低50％以上，同时满足经济性、动力性以及操作性能等要求，此外，也可以切换为单独燃烧柴油，而不改变发动机的原有性能。该系统结构简单、成本低廉，非常适合于改装城市在用公交车，降低其黑烟排放。     

What’s in a name? Drivers’ perceptions of the use of five SAE Level 2 driving automation systems

Introduction: Automobile manufacturers are developing increasingly sophisticated driving automation systems. Currently, the highest level of automation available on the market is SAE Level 2, which provides sustained assistance for both lateral and longitudinal vehicle control. The purpose of this study was to evaluate how drivers’ perceptions of what behaviors secondary to driving are safe while a Level 2 system is operating vary by system name. Methods: A nationally representative telephone survey of 2005 drivers was conducted in 2018 with questions about behaviors respondents perceived as safe while a Level 2 driving automation system is in operation. Each respondent was asked about two out of five system names at random for a balanced study design. Results: The name “Autopilot” was associated with the highest likelihood that drivers believed a behavior was safe while in operation, for every behavior measured. There was less variation observed among the other four SAE Level 2 system names when compared with each other. A limited proportion of drivers had experience with advanced driver assistance systems and fewer of these reported driving a vehicle in which Level 2 systems were available. Drivers reported that they would consult a variety of sources for information on how to use a Level 2 system. Conclusions: The names of SAE Level 2 driving automation systems influence drivers’ perceptions of how to use them, and the name “Autopilot” was associated with the strongest effect. While a name alone cannot properly instruct drivers on how to use a system, it is a piece of information and must be considered so that drivers are not misled about the correct usage of these systems. Practical Applications: Manufacturers, suppliers, and organizations regulating or evaluating SAE Level 2 automated driving systems should ensure that systems are named so as not to mislead drivers about their safe use.     

Results from a national survey of Crown prosecutors and defense counsel on impaired driving in Canada: A “System Improvements” perspective

Introduction

This article summarizes the main findings from a study designed to examine the legal process in Canada as it applies to alcohol-impaired driving from the point of view of Crown prosecutors and defense counsel, and to identify evidentiary or procedural factors that may impact the legal process, the rights of the accused, and interactions of all parts in the legal process.

Method

The data in this study were collected by means of a survey that was mailed out to the population of Crown prosecutors and defense counsel in Canada. In total, 765 prosecutors and 270 defense lawyers or an estimated 33% of all Canadian prosecutors and 15% of defense lawyers completed and returned the questionnaire. The "systems improvement" paradigm was used to interpret the findings and draw conclusions. Such an approach acknowledges the importance of the context in which countermeasures are implemented and delivered and the structures or entities used to deliver countermeasures to a designated target group.

Results

Results on type of charges and breath alcohol concentration, caseload, case outcomes, case preparation time, conviction rate at trial and overall conviction rate, reasons for acquittals and time to resolve cases are described.

Discussion

The findings from this national survey suggest that there are important challenges within the criminal justice system that impede the effective and efficient processing of impaired driving cases. Some of these challenges occur as a function of practices and policies, while others occur as a function of legislation.

Impact on industry

This study illustrates that a "system improvements" approach that acknowledges the importance of all elements of the criminal justice system and the interaction between those elements, can be beneficial in overcoming the alcohol-impaired driving problem.     

Trends in young driver risk and countermeasures in European countries

This paper reviews European trends regarding young drivers' accident risk and the effects of countermeasures. Young driver risk differs between countries, and has improved in the last decade, probably as a result of general improvements in road safety levels. Young male drivers' relative risk is rising, indicating that current policies are less effective for males than for females. Further research is needed to understand the causes of this development. In Europe, most countries are moving toward multiphase licensing systems, including elements like accompanied driving, protective measures, and probation periods. European evaluation studies show mixed results regarding these elements, pointing to a need for more research into the effective components.     

Comparison of portable and onboard navigation system for the effects in real driving

Navigation systems are very useful and popular tools which display a user’s location and make use of graphics, text and voice information to guide him to a predetermined destination. Recently, some researches had revealed that drivers choose to receive driving directions using portable devices owing to their price and convenience. This study aimed to survey whether the driving efficiency and controlling are different as using portable and onboard navigation systems. A smartphone (2.7″ screen) and driving support system we instructed (8.9″ display interface) were adopted as the portable and onboard navigation systems respectively. Thirty subjects were paid to participate in this study, and field experiments were executed in urban and rural environments. Participants were randomly divided into two groups with equal numbers and drove according to instructions provided by one of these systems. The results indicated that the performance of drivers using the portable navigation system is better than that of the onboard one, in terms of efficiency and car handling, both in the urban and rural environments, despite the fact that the display screen of the phone is so small.     

Assessing drivers' response during automated driver support system failures with non-driving tasks

IntroductionWith the increase in automated driver support systems, drivers are shifting from operating their vehicles to supervising their automation. As a result, it is important to understand how drivers interact with these automated systems and evaluate their effect on driver responses to safety critical events. This study aimed to identify how drivers responded when experiencing a safety critical event in automated vehicles while also engaged in non-driving tasks.MethodIn total 48 participants were included in this driving simulator study with two levels of automated driving: (a) driving with no automation and (b) driving with adaptive cruise control (ACC) and lane keeping (LK) systems engaged; and also two levels of a non-driving task (a) watching a movie or (b) no non-driving task. In addition to driving performance measures, non-driving task performance and the mean glance duration for the non-driving task were compared between the two levels of automated driving.ResultsDrivers using the automated systems responded worse than those manually driving in terms of reaction time, lane departure duration, and maximum steering wheel angle to an induced lane departure event. These results also found that non-driving tasks further impaired driver responses to a safety critical event in the automated system condition.ConclusionIn the automated driving condition, driver responses to the safety critical events were slower, especially when engaged in a non-driving task.Practical applicationTraditional driver performance variables may not necessarily effectively and accurately evaluate driver responses to events when supervising autonomous vehicle systems. Thus, it is important to develop and use appropriate variables to quantify drivers' performance under these conditions.     

基于多元子代理模块系统(MAS)的单司机值乘驾驶安全可靠性研究

介绍并分析影响单司机值乘驾驶安全可靠性的因素,强调单司机值乘人-机-环境系统安全性中人行为的重要性,提出利用MAS模型对单司机值乘的安全可靠性进行分析。介绍该模型的标定过程,给出其驾驶行为的安全可靠度和Agent模型结合在一起来确定司机决策行为的过程和方法。为提高我国单司机值乘驾驶安全性提供了一种研究方法。     

Comprehensive alarm information processing technology with application in petrochemical plant

During the abnormal plant conditions, too much information is produced due to momentary plant excursions above alarm limits. This flood of information impedes correct interpretation and correction of plant conditions by the operator. Existing techniques for the design of alarm systems mostly have weak ability to handle complex hazard scenarios and increase the probability of larger safety issues. In this paper, a comprehensive alarm information processing (AIP) technology is introduced, called multi-round alarm management system (MRAMS), including several processing strategies: AIP based on single sensor, AIP based on sensor group, root cause diagnosis based on Bayesian network, sensor fault judgment method and false alarm inhibition method. In case studies, both simulation experiment and pilot application on a real petrochemical plant are presented. Results indicate the MRAMS is helpful in improving the accuracy of correctly diagnosing the root causes and hence avoiding false and redundant alarms. By adopting this new technology, the safe and reliable operation of the plant can be achieved, and the economic loss brought by improper alarms can be reduced.     

Critical aspects for collision induced oil spill response and recovery system in ice conditions: A model-based analysis

The recovery effectiveness for oil spills in ice conditions depends on a complex system and has not been studied in depth, especially not from a system risk control perspective. This paper aims to identify the critical aspects in the oil spill system to enable effective oil spill recovery. First, a method is developed to identify critical elements in a Bayesian Network model, based on an uncertainty-based risk perspective. The method accounts for sensitivity and the strength of evidence, which are assessed for the different Bayesian Network model features. Then, a Bayesian Network model for the mechanical oil spill recovery system is developed for the Finnish oil spill response fleet, contextualized for representative collision accident scenarios. This model combines information about representative sea ice conditions, ship-ship collisions and their associated oil outflow, the oil dispersion and spreading in the ice conditions, and the oil spill response and recovery of the fleet. Finally, the critical factors are identified by applying the proposed method to the developed oil spill response system model. The identified most critical system factors relates collision aspect: Forcing Representative Scenario, Representative Accident Location, Impact Speed, Impact Location, Impact Angle and response aspect: Response Vessel Operability.     

基于PLIF的混合气温度和浓度测量及其应用

缸内混合气温度和浓度分布,对发动机稳定运行,保障行车安全、避免发生路上人身伤亡或财物损失有重要影响。为了测量发动机缸内混合气的温度和浓度分布,建立了利用单波长激光诱导双示踪剂产生双荧光的测试系统,并拍摄了不同混合气温度、压力和浓度下的荧光图像,获得了不同示踪剂的荧光强度及其比值随温度、压力和浓度的变化关系,并将标定结果用于光学发动机缸内混合气的温度和浓度测量。结果表明,荧光强度及荧光比值均受到环境的压力、温度和混合气浓度的影响。利用PLIF方法得到的片光源穿过的缸内水平截面内的平均温度与用气缸压力计算的同一曲轴转角下的缸内平均温度变化趋势相同,两者之间的差值随着活塞上行而逐步减小。     

Experiences from dual-country drivers: Driving safely in China and the US

This study explored the international experience of driving in two countries from the perspectives of drivers. It highlighted the differences in driving experiences between China and the US from people who have driven in both countries. A qualitative research approach utilizing focus group discussions was conducted in China and the US. The pros and cons, strengths and weaknesses of the transportation systems in the two countries were discussed. Car accidents or near misses due to differences between the two countries were explored. Advice for people who want to drive in these two countries as foreign visitors was discussed. Results showed that there are strengths and weaknesses in both countries in their driving systems. Both countries could benefit from exploring the traffic and roadway system of the other.     

Real-time leak detection in oil pipelines using an Inverse Transient Analysis model

Based on Inverse Transient Analysis (ITA) method, a real-time leak detection method is proposed to capture leak location and the associated leak rate in oil pipe conveyance systems. In the proposed approach, location and flow rate of leak (if any), the fluid properties, as well as physical parameters of the system, are calculated in consecutive periods through minimizing the discrepancy between the calculated and measured flow parameters of the system. The method of characteristics is employed to numerically calculate the transient responses of the system and the genetic algorithm is utilized as the optimization engine. The proposed approach was applied to several real pipeline systems in which the required transient flow data are either directly collected from the field or fabricated with a third-party numerical software. Extensive numerical explorations were conducted to investigate the performance of the proposed method in real-time leak detection and to determine the extent to which field data errors, stemming from Supervisory Control and Data Acquisition (SCADA) systems and measurement equipment, affect the leak flow rate and location detectability of the proposed approach. The results show that the proposed approach provides promising results under a variety of transient and steady-state flow conditions even in the case with small leak flow rate of around 2% of the line rate. The results also reveal that the noises in the measurement data and the errors originated from SCADA systems do not significantly compromise the leak detectability of the proposed approach, confirming that the proposed approach can be utilized in practice.     

The effect of extending graduated driver licensing to older novice drivers in Indiana

Introduction: Graduated driver licensing (GDL) systems have been shown to reduce rates of crashes, injuries, and deaths of young novice drivers. However, approximately one in three new drivers in the United States obtain their first driver’s license at age 18 or older, and thus are exempt from most or all provisions of GDL in most states. Method: In July 2015, the state of Indiana updated its GDL program, extending its restrictions on driving at night and on carrying passengers during the first 6 months of independent driving, previously only applicable to new drivers younger than 18, to all newly-licensed drivers younger than 21 years of age. The current study examined monthly rates of crashes per licensed driver under the affected conditions (driving at night and driving with passengers) among Indiana drivers first licensed at ages 18, 19, and 20 under the updated GDL system compared with drivers licensed at the same ages under the previous GDL system. We used Poisson regression to estimate the association between the GDL system and crash rates, while attempting to control for other factors that might have also influenced crash rates. We used linear regression to estimate the association between the GDL system and the proportion of all crashes that occurred under conditions restricted by the GDL program. Results: Results showed, contrary to expectations, that rates of crashes during restricted nighttime hours and with passengers were higher among drivers licensed under the updated GDL system. This mirrored a statewide increase in crash rates among drivers of all ages over the study period and likely reflected increased overall driving exposure. The proportions of all crashes that were at night or with passengers did not change. Practical Applications: More research is needed to understand how older novice drivers respond when GDL systems originally designed for younger novice drivers are applied to them.     

系统安全相似分析法及其应用

系统安全相似分析法是发掘共性事故致因,运用逻辑学和数学方法解决安全问题的方法。通过评价比较分析法、比较安全法、模糊相似分析法与系统相似分析法的优缺点,采用多隶属模糊集对系统相似分析法进行改进,克服其无法度量模糊因素相似性的缺陷,得到适用于模糊系统的系统安全相似分析法。基于此,建立系统安全相似度计算数学模型,并构建系统安全相似分析范式。将改进的分析方法应用于4起典型煤矿瓦斯爆炸事故,分析得出,越界开采、井下密闭作业、应急救援不力、密不上报、拒不撤出作业人员等是造成瓦斯爆炸事故严重程度升级的主要因素;物质流、能量流、信息流相似度接近于1,然而其对造成事故的潜在影响受到忽视,是煤矿避免瓦斯爆炸事故的极佳着手点。结果表明,这一改进有效实现了事故致因因素的相似性度量,为系统安全分析与事故预防提供了新思路与新方法。