A safety analysis of roundabouts and turbo roundabouts based on Petri nets

Objective: In this work, a roundabout and a turbo roundabout model are compared and previous modeling with continuous Petri nets and safety are analyzed through indicators of complexity. Petri nets are a graphic and mathematical representation that allow a faithful modeling of urban systems.

Method: The methodology has been designed for the transformation of a real system to small subgraphs that represent the maneuvers in roundabouts, approximated as roads and lanes of incorporation. Places within the roundabout have been located and defined as continuous places from their influence and visibility toward adjacent conditions. The transitions have been modeled by time and inhibitory arcs, which represent priorities and areas where drivers must pay attention. The created networks represent a faithful model of vehicle flow trajectories in the roundabouts.

Results: The methodology is applied to the same real road intersection. The case study is a recent transformation from roundabout to turbo roundabout. The roundabout network complexity is corroborated by a greater number of entries and exits that lead to each roundabout place (reflected in the maneuvers that can be performed) and a greater number of inhibiting arcs. In most of the turbo roundabout places, the driver’s only option is reduced to occupying next place. The possibility of choosing between several places supposes a greater trajectory intersection and an increased time for decision making. The only situation where the complexity is the same between both systems is when a vehicle accesses the inner lane of the roundabout from the left lane on a single-lane road. The main maneuvers causing accidents have been modeled and their solution in a turbo roundabout is presented.

Conclusions: The reduced complexity of the turbo roundabout is due to the strict limitations in lane changes, turning turbo roundabouts into a safer model: A lower number of possible movements that can be performed by drivers and a smaller number of trajectories with collision risk. Petri nets have proven to be perfectly applicable to the representation of traffic circular systems (such as roundabouts and turbo roundabouts) and to measure the complexity and security of the system.     

Road safety in China: Analysis of current challenges

Introduction

China has the world's largest population, and is the second largest automobile market. China's economy is booming, resulting in a rapid increase in both the road infrastructure and access to private vehicles. Along with economic growth, the ownership of motorized vehicles has almost quadrupled in the past 10 years, from 42.2 million in 1997 to 159.7 million in 2007. However, at the same time, China also has a very high number of road fatalities compared to other countries, with about 100,000 reported fatalities each year.

Method

This study analyzes the Chinese road-fatality situation to identify areas in which the total harm caused by crashes can be substantially and readily reduced. It provides a comprehensive analysis of the current road-fatality situation in China using conventional indices and the likely future trends.

Results

Four areas were identified in which countermeasures have the most potential to substantially reduce fatalities in China: pedestrians and other non-motorists, nighttime driving, vehicle passengers, and motorcycles.

Conclusion

While China faces unprecedented road safety issues, this report identifies major areas in which there are opportunities to greatly reduce total harm.     

建筑企业安全文化对安全绩效影响的实证研究

基于安全文化在建筑业安全管理中的重要性越来越突出,因此安全文化对于提高安全绩效,减少建筑业事故发生率的作用日益得到重视。文中进行实证研究,探讨建筑企业安全文化对安全绩效的影响。安全文化的维度为安全制度文化、安全物质文化和安全观念文化,研究结果表明,安全制度文化、安全物质文化和安全观念文化均有助于安全绩效提高,研究结果可在一定程度上促使建筑企业重视并自觉改善安全文化,有助于减少建筑业安全事故发生率,提升安全绩效。     

Road traffic injuries to foreigners in the People's Republic of China, 2000-2008

Introduction: China's rapid motorization has resulted in significant challenges in road safety. Method: Using official national statistics, this study examines road traffic injuries (RTIs) experienced by foreigners in China. The number of foreigners entering China has increased 2.4 times over the study period, from 10.16 million in 2000 to 24.33 million in 2008. Results: From 2000- 2008, the number of road traffic fatalities among foreigners similarly increased 2.5 fold, including 49 fatalities reported in 2008. Nonfatal RTIs during this same time frame increased by a magnitude of 1.8 (126 nonfatal injuries in 2000 to 223 in 2008). Conclusions: This study suggests that the total number of foreigners working or visiting China each year who suffer fatal and nonfatal road traffic injuries is relatively low. Impact on Industry: This study provided evidence suggesting that foreigners visiting or working in China face a relatively low risk of road traffic injuries.     

Estimating the variance in before-after studies

Problem

To simplify the computation of the variance in before-after studies, it is generally assumed that the observed crash data for each entity (or observation) are Poisson distributed. Given the characteristics of this distribution, the observed value (x_i) for each entity is implicitly made equal to its variance. However, the variance should be estimated using the conditional properties of this observed value (defined as a random variable), that is, f(x_i|μ_i), since the mean of the observed value is in fact unknown.

Method

Parametric and non-parametric bootstrap methods were investigated to evaluate the conditional assumption using simulated and observed data.

Results

The results of this study show that observed data should not be used as a substitute for the variance, even if the entities are assumed to be Poisson distributed. Consequently, the estimated variance for the parameters under study in traditional before-after studies is likely to be underestimated.

Conclusions

The proposed methods offer more accurate approaches for estimating the variance in before-after studies.     

模糊神经网络技术在矿山安全评价中的适应性研究

我国矿山企业安全生产形势严峻,矿山安全一直是我国矿山企业急需解决的安全评价技术及其应用是预防和控制矿山灾害事故的重要内容.对国内外矿山安全评价理论和技术的研究进展进行了系统的论述,并对国内安全评价理论和技术的研究和应用过程出现的问题进行了分析,指出模糊神经网络技术在矿山安全研究中的可行性,为矿山安全管理和科学决策提供了一种新的思路.     

我国工业企业安全科技需求问题的探讨

安全生产是一个庞大的系统工程，安全科学研究工作是这个庞大系统工程中的重要链条之一。安全科学研究工作的深度和广度对安全生产具有重大促进作用。围绕我国安全生产面临的实际问题，搞好重大安全科学研究课题的论证和列项，是争取快出成果和培养有用人才的一个不可忽视的问题．     

技改项目劳动安全卫生评价方法与问题

介绍了天津钢管有限责任公司技术改造项目劳动安全卫生评价的做法与收获,并对评价过程中存在的问题及解决方法进行了探讨。     

The safety observer effect: the effects of conducting safety observations

INTRODUCTION: Some research suggests that conducting safety observations of another's safety performance may serve as an effective tool in increasing the safety performance of the observer. The primary purpose of the present study was to assess the effects of conducting safety observations on the postural safety performance of observers engaging in an assembly task for short time periods. The secondary objectives of the study were: (a) to measure productivity, and (b) to measure the accuracy of participant safety observations. METHOD: An ABC (A: baseline, B: information, C: observation) multiple-baseline design counterbalanced across postural behaviors (back, shoulder, and feet position) was implemented with six participants. RESULTS AND DISCUSSION: Substantial improvements in postural safety occurred after participants conducted safety observations, and these improvements did not appear to negatively affect productivity. Results also suggest that there is no relation between the accuracy of an observer's safety observation and their subsequent safety performance. IMPACT ON INDUSTRY: This research provides evidence that a safety observation process can function to increase safe postural behavior of observers. Thus, the implementation of such a process may contribute to the prevention of musculoskeletal disorders and related costs in the workplace.     

Deterioration of the useful visual field with ageing during simulated driving in traffic and its possible consequences for road safety

A previous study has shown that the useful visual field deteriorates in a simulated road traffic situation as a function of the driver’s age and of the vehicle’s speed under monotonous conditions [Rogé, J., Pébayle, T., Lambilliotte, E., Spitzenstetter, F., Giselbrecht, D., Muzet, A., 2004. Influence of age, speed and duration of monotonous driving task in traffic on the driver’s useful visual field. Vision Research 44 (23), 2737–2744]. The aim of this new experiment is to study the effects of traffic density and age on the useful visual field of the driver during a simulated driving task with controlled traffic characteristics (speed, number of cars) for all participants. In total, 10 young drivers (m = 28.2 years) and 10 older drivers (m = 51.2 years) followed a car in road traffic at an average speed of 126 km h⁻¹ during two 2 h sessions corresponding to two conditions of traffic (light traffic, with five vehicles around the participant; and heavy traffic, with nine vehicles). While following this vehicle, the driver had to detect changes in the colour of a signal located in the central part of his or her visual field and a signal that appeared at different eccentricities on the rear lights of other vehicles in the traffic. Analysis of the data indicated that age interacted with the location of the peripheral signal and density of traffic interacted with the duration of driving. The implications of these results are discussed in terms of road safety and in terms of models of deterioration of the useful visual field (general interference and tunnel vision).     

胜利油田推行安全经济管理的可行性分析

社会主义市场经济形势,决定了安全生产工作实行经济管理的必然性和可行性。安全经济管理效益有"滞后效应"的"隐形"性的特点,我们在实践操作中,不但要关心采取哪一种安全管理方案或措施所获得的安全水平最高,减少事故的效果最好,而且也要研究哪种方案或措施能够实现最省时、所投入的费用最少、达到的安全效果最好。实际上是把安全经济管理当作一种投资活动,怎样通过最小的投入获取最大化的投资收益。我们既要研究直接效果和间接效果,还要研究近期效果和远期效果;不仅要从局部单位出发计算经济效果,还要从全企业整体出发计算近期和远期的经济效果。在胜利油田推行安全经济管理应搞好"三同时"管理、开展安全管理经济评价、运用经济手段加强安全管理等工作。我们应建立胜利油田安全经济管理效益评价体系,寻找提高油田安全经济管理效益的新途径。     

安全系统的功能安全的发展及实施建议

安全系统的功能安全是基于整体安全生命周期的风险控制与管理,是安全管理学和安全监控技术的新发展。有效的开展功能安全相关工作是进一步落实科技兴安战略和预防为主方针的必然要求,对于减低安全生产事故风险,提高安全监控监管监察效能,缩小安全技术差距具有重要意义。实施功能安全相关工作需要各行业协调行动,从战略高度进行综合分析、宏观设计、统筹安排和合理规划。对功能安全研究与应用、安全生产法规标准、产业发展、科研试验、人才队伍等方面进行了探讨,在加大功能安全相关研发投入,增强科技扶持力度,提高功能安全准入门槛,建设功能安全认证服务机构,发展功能安全产业,培养功能安全专业人才等方面提出了相应的建议措施。     

"安全科学学"理论与实践——20世纪80年代安全科学学科在我国初创纪实

从劳动保护科学概念入手,介绍了"安全技术与工程学"学科、专业的诞生过程,较详实地记录了20世纪80年代安全科学学科初创的始末.从中国劳动保护科学技术学会成立与安全工程试办专业的确立到安全科学学科概念及安全科学技术体系结构模型的提出,见证了从理论探索到实践认识提高与应用的过程.安全科学学科创建时期是我国安全科学理论与实践的一个重要阶段.     

\"The little squealer\" or \"the virtual guardian angel\"? Young drivers' and their parents' perspective on using a driver monitoring technology and its implications for parent-young driver communication

Introduction

In-vehicle driving monitoring technologies have the potential to enable young drivers to learn from self-assessment. However, their use is largely dependent on parental involvement.

Method

A total of 79 interviews were conducted with young drivers and parents regarding this technology and its use. Most had the experience of having an in-vehicle data recorder installed in the vehicle driven by the young drivers. Parents and the young drivers expressed both appreciation as well as reservations about its potential as a means to enhance the driving safety of young drivers.

Results

A surprising finding was that some parents did not check the feedback and said they relied on the young driver to do so. Main concerns related to privacy, parent-young driver relationship, self-esteem and confidence, constructive use of the feedback data, and the limitations of the documentation that can be done by the technology.

Conclusions

Providing parents and young drivers with a support system and tools to discuss and utilize the feedback are underscored. Challenges include addressing the invasion of young drivers’ privacy and gender differences, and using the monitoring-capacity of the technology to enhance safe driving practices. Implications for programs to enhance communication and a dialogical approach between parents and young drivers are discussed.     

Impact of Adaptive Front-lighting Systems (AFS) on road safety: Evidences and open points

Almost four years after the entry into force of Regulation ECE 123 on Adaptive Front-lighting Systems (AFS) for motor vehicles, and once the first cars bearing them start to circulate, a comparison between the original idea of AFS and their potential impact in safety and accident prevention is possible. In this work, we present the basic concepts of this new way to light roads and analyse some unforeseen consequences that might arise within the ECE regulatory framework once the presence of AFS becomes massive. This paper also pretends to be an useful guide for some countries like China, still considering the best way to definitively regulate these complex systems whose impact on road safety is expected to be huge.     

An observational study of child safety seat use in an international safe community: Tehran,Iran

Objective: Despite strong evidence of the effectiveness of child safety seats in reducing injuries, the use of these devices in some communities is still rare. The purpose of this study was to determine the prevalence of child safety seat use and the factors influencing its use in the safe community of Tehran.

Methods: This roadside observational study was conducted in 2015 and 2,178 personal cars with a child under 12 years aboard were observed on Tehran's streets in regard to use of child safety seats. Other variables such as the gender of the driver, driver's age group, type of street, region of municipality, time of day, and day of the week were also collected.

Results: Prevalence of child safety seat use was 4.3% and was significantly higher among women drivers, on freeways, and in municipal regions 1, 4, and 7.

Conclusions: The prevalence of child safety seat use in Tehran as a most populous member of the international safe community was very low and most children commuted in insecure situations in the vehicle. Therefore, it is proposed that plans should be made to increase the use of child safety seats in international safe communities.     

安全文化建设在首钢大石河铁矿运用的体会

首钢大石河铁矿坚持“以人为本” ,大力加强“安全文化”建设 ,为职工的生命安全营造了绿色屏障     

New findings regarding the significance of pavement skid resistance for road safety on Swiss freeways

INTRODUCTION: The significance of the influence of poor pavement skid resistance values on accident frequency in wet pavement conditions has been the object of many studies over several years. The various investigations have produced very diverse findings. Only seldom, however, has detailed consideration been given to the central question of whether pavement skid resistance is a decisive parameter in the occurrence of local accident "black spots." Until now, the focus has been more on describing a relationship between pavement skid resistance and accident frequency. METHOD AND RESULTS: In the course of the network-wide survey of the states of pavements and of accident occurrence on Switzerland's freeways from 1999 to 2003, it emerged that a relationship with inadequate pavement skid resistance was provable for only a small proportion of accident black spots. These findings were used to frame a guideline for authorities and highway operators about how to treat skid resistance when assessing pavements and accident occurrence on freeways.     

限速值对信号交叉口交通安全的影响分析

为研究交叉口进口道车辆限速值对交叉口的安全和运行产生的影响,通过微观仿真平台,分析车辆在交叉口限速分别为30,38和46 km/h时的车均延误、车均行程时间,并将车辆行驶轨迹输入安全辅助评价(SSAM)软件中展开分析。结果表明,车辆限速值的提高对车均延误的影响不大,但会减小车辆在进口道的车均行程时间。另外,限速值从30 km/h提高到46 km/h,引起的碰撞时间(TTC)、后侵占时间(PET)数值变化不显著,但使总冲突数从42个增加到59个。     

Injury crashes with bicyclists at roundabouts: influence of some location characteristics and the design of cycle facilities

Problem

Previous research indicated that conversions of intersections into roundabouts appear to increase the number of injury crashes with bicyclists. However, it was assumed that the effectiveness of roundabouts could vary according to some differences in design types of cycle, facilities and other geometrical factors.

Method

Regression analyses on effectiveness-indices resulting from a before-and-after study of injury crashes with bicyclists at 90 roundabouts in Flanders, Belgium.

Results

Regarding all injury crashes with bicyclists, roundabouts with cycle lanes appear to perform significantly worse compared to three other design types (mixed traffic, separate cycle paths, and grade-separated cycle paths). Nevertheless, an increase of the severest crashes was noticed, regardless of the design type of the cycle facilities. Roundabouts that are replacing signal-controlled intersections seem to have had a worse evolution compared to roundabouts on other types of intersections.

Impact on industry

The results might affect design guidelines for roundabouts, particularly for the accommodation of bicyclists.