Analyzing injury severity factors at highway railway grade crossing accidents involving vulnerable road users: A comparative study

Objective: The main objective of this study is to identify the main factors associated with injury severity of vulnerable road users (VRUs) involved in accidents at highway railroad grade crossings (HRGCs) using data mining techniques.

Methods: This article applies an ordered probit model, association rules, and classification and regression tree (CART) algorithms to the U.S. Federal Railroad Administration's (FRA) HRGC accident database for the period 2007–2013 to identify VRU injury severity factors at HRGCs.

Results: The results show that train speed is a key factor influencing injury severity. Further analysis illustrated that the presence of illumination does not reduce the severity of accidents for high-speed trains. In addition, there is a greater propensity toward fatal accidents for elderly road users compared to younger individuals. Interestingly, at night, injury accidents involving female road users are more severe compared to those involving males.

Conclusions: The ordered probit model was the primary technique, and CART and association rules act as the supporter and identifier of interactions between variables. All 3 algorithms' results consistently show that the most influential accident factors are train speed, VRU age, and gender. The findings of this research could be applied for identifying high-risk hotspots and developing cost-effective countermeasures targeting VRUs at HRGCs.     

装备典型舰载平台振动环境严酷度分析

目的为了正确识别舰载环境。方法采用INV3062T2数据采集系统,在典型舰载平台上实测了装备在舱室内的振动环境。结果数据表明,舱室内各方向上的振动加速度是一个正态随机变量,得到了各方向加速度峰值和振动加速度谱密度。结论分析表明,舱室内典型振动环境属于I型,是一类长期存在但量值较小的振动环境。     

行人过街空间违章行为特性及安全影响分析*

为探究提前右转车道处不同因素与人车冲突的相关性,以及行人空间违章对过街安全的影响。采集2 062个行人及人车冲突的样本数据,获取行人和机动车的时空信息,对比分析不同类型行人过街轨迹的特征;综合考虑人车冲突时间和速度指标构建人车冲突严重度指标,从行人生理特征、车流条件、道路环境等方面选取8个因素作为自变量,构建人车冲突严重度的多元有序Logistic模型。研究结果表明:空间违章过街的行人平均过街速度和速度离散程度都明显高于其他行人;年龄、车速、人行横道长度、车辆到达率以及过街轨迹类型都是影响人车冲突严重程度的重要因素。各类型空间违章行为使严重冲突占比均提升75%以上。研究结果有助于交管部门采取措施保障行人过街安全。     

Examining traffic crash injury severity at unsignalized intersections

Introduction

This study presents multiple approaches to the analysis of crash injury severity at three- and four-legged unsignalized intersections in the state of Florida from 2003 until 2006. An extensive data collection process was conducted for this study.

Method

The dataset used in the analysis included 2,043 unsignalized intersections in six counties in the state of Florida. For the scope of this study, there were three approaches explored. The first approach dealt with the five injury levels, and an ordered probit model was fitted. The second approach was an aggregated one, and dealt with only the severe versus non-severe crash levels, and a binary probit model was used. The third approach dealt with fitting a nested logit model. Results from the three fitted approaches were shown and discussed, and a comparison between the three approaches was shown.

Results

Several important factors affecting crash severity at unsignalized intersections were identified. These include the traffic volume on the major approach, and the number of through lanes on the minor approach (surrogate measure for traffic volume), and among the geometric factors, the upstream and downstream distance to the nearest signalized intersection, left and right shoulder width, number of left turn movements on the minor approach, and number of right and left turn lanes on the major approach. As for driver factors, young and very young at-fault drivers were associated with the least fatal probability compared to other age groups.

Impact on industry

The analysis identified some countermeasures to reduce injury severity at unsignalized intersections. The spatial covariates showed the importance of including safety awareness campaigns for speeding enforcement. Also, having a 90-degree intersection design is the most appropriate safety design for reducing severity. Moreover, the assurance of marking stop lines at unsignalized intersections is very essential.     

Rapid Increases and Time‐Lagged Declines in Amphibian Occupancy after Wildfire

Climate change is expected to increase the frequency and severity of drought and wildfire. Aquatic and moisture‐sensitive species, such as amphibians, may be particularly vulnerable to these modified disturbance regimes because large wildfires often occur during extended droughts and thus may compound environmental threats. However, understanding of the effects of wildfires on amphibians in forests with long fire‐return intervals is limited. Numerous stand‐replacing wildfires have occurred since 1988 in Glacier National Park (Montana, U.S.A.), where we have conducted long‐term monitoring of amphibians. We measured responses of 3 amphibian species to fires of different sizes, severity, and age in a small geographic area with uniform management. We used data from wetlands associated with 6 wildfires that burned between 1988 and 2003 to evaluate whether burn extent and severity and interactions between wildfire and wetland isolation affected the distribution of breeding populations. We measured responses with models that accounted for imperfect detection to estimate occupancy during prefire (0–4 years) and different postfire recovery periods. For the long‐toed salamander (Ambystoma macrodactylum) and Columbia spotted frog (Rana luteiventris), occupancy was not affected for 6 years after wildfire. But 7–21 years after wildfire, occupancy for both species decreased ≥25% in areas where >50% of the forest within 500 m of wetlands burned. In contrast, occupancy of the boreal toad (Anaxyrus boreas) tripled in the 3 years after low‐elevation forests burned. This increase in occupancy was followed by a gradual decline. Our results show that accounting for magnitude of change and time lags is critical to understanding population dynamics of amphibians after large disturbances. Our results also inform understanding of the potential threat of increases in wildfire frequency or severity to amphibians in the region. Incrementos Rápidos y Declinaciones Desfasadas en la Ocupación de Anfibios Después de un Incendio     

Factors associated with occupational injury severity in the New South Wales underground coal mining industry

The relationship between a large number of mine and mine worker characteristics and injury severity was examined using multiple regression techniques. The study was based on data extracted from the New South Wales (N.S.W.) Joint Coal Board's computer based accident/incident reporting system describing 21,372 non-fatal, lost-time injurious incidents that occurred in the N.S.W. underground coal mining industry during the 4 year period from 1 July 1986 to 30 June 1990. The number of days lost as a result of an injurious incident was the best available proxy measure of injury severity. Over the study period, the number of days lost per 100,000 tonnes of raw coal production declined by 73%. Over the same period, injurious incidents involving more than 20 days off work, which constituted only 16% of all injurious incidents in underground mines, resulted in 75% of the total days lost for the whole N.S.W. underground coal mining industry. Factors that had practical importance and that were significantly associated with injury severity included mine worker's age, part of the body injured, type of accident, agency of accident, and mine worker activity. Factors not important or not significant in their relationship with injury severity were: time into shift, previous hours worked, mine location of incident, occupation, work experience, frequency of task, shift, and mining region. This study suggests that factors related to the susceptibility of a mine worker's body tissue to damage or repair, and factors related to the concentration of energy on the mine worker by vehicle and environmental characteristics are important determinants of injury severity.     

The Relationship Between Road Accident Severity and Recorded Weather

Road accident severity may be influenced by a number of factors. This article investigates the relationship between weather and road accidents in England and Wales. The weather information recorded on Police Accident Report Forms was taken as the prevailing weather at the time of the accident. At the local authority level, accident severity for the various adverse weather categories of rain, fog, and high winds is compared with the nonhazardous condition of fine weather. Severity ratios are then calculated. Findings establish that accident severity decreases significantly in rain compared with fine weather, while severity in fog shows geographical variation. Evidence for accident severity in high winds remains inconclusive.     

基于大坝安全鉴定和专家经验的病险程度评价技术

针对目前我国大坝安全鉴定办法在病险水库严重程度评价中的不足,提出一种大坝病险严重程度的评价方法。以现行大坝安全鉴定技术和专家经验为基础,将水库大坝病险分为五级;提出病险严重性分级以及定性定量转换原则;建立防洪能力、渗流、稳定、变形裂缝、抗震能力、金属结构、工程质量、运行管理、现场检查9个评价大坝病险程度因素的指标体系以及分级和定性-定量转换方法;采用线性加权和法进行病险严重程度综合评价;研究并提出病险程度综合评价影响系数模型以及两种权重确定方法;建立了一套较为完整的病险程度综合评价体系。通过举例分析,提供了使用该方法的途径和过程,表明该方法的可操作性,可行性和实用性。     

Perceived safety climate, job demands, and coworker support among union and nonunion injured construction workers

PROBLEM: This study evaluated injured construction workers' perceptions of workplace safety climate, psychological job demands, decision latitude, and coworker support, and the relationship of these variables to the injury severity sustained by the workers. METHODS: Injury severity was assessed using the Health Assessment Questionnaire (HAQ), which evaluates functional limitations. Worker perceptions of workplace variables were determined by two instruments: (a) the Safety Climate Measure for Construction Sites and (b) the Job Content Questionnaire (JCQ). RESULTS: The overall model explained 23% of the variance in injury severity, with unique contributions provided by union status, the Safety Climate Score, and Psychological Job Demands. A positive significant correlation was found between injury severity and the Safety Climate Scores (r = .183, P = .003), and between the Safety Climate Scores and union status (r = .225, P < .001). DISCUSSION: There were statistically significant differences between union and nonunion workers' responses regarding perceived safety climate on 5 of the 10 safety climate items. Union workers were more likely than nonunion workers to: (a) perceive their supervisors as caring about their safety; (b) be made aware of dangerous work practices; (c) have received safety instructions when hired; (d) have regular job safety meetings; and (e) perceive that taking risks was not a part of their job. However, with regard to the 49-item JCQ, which includes Coworker Support, the responses between union and nonunion workers were very similar, indicating an overall high degree of job satisfaction. However, workers who experienced their workplace as more safe also perceived the level of management (r = -.55, P < .001) and coworker (r = -.31, P < .001) support as being higher. IMPACT ON INDUSTRY: The findings of this study underscore the critical need for construction managers to alert workers to dangerous work practices and conditions more frequently, and express concern and praise workers for safe work in a manner that is culturally acceptable in this industry. Workplace interventions that decrease the incidence and severity of injuries, but that are flexible enough to meet a variety of potentially competing imperatives, such as production deadlines and client demands, need to be identified.     

重庆市城区地质灾害分级评价研究

我国是世界上地质灾害最严重的国家之一。本文以重庆市为例,对九大城区各种地质灾害进行分级评价,根据本地区实际情况,得到灾害发生的频率和严重度,从而计算出灾害指数。利用这种方法,可以简单直观地对各种地质灾害进行危害程度的评价。