Driver behaviour, dilemma zone and safety effects at urban signalized intersections in Greece

Driving behaviour at signalized intersections is one of the main factors contributing to the safety level of such entities. This behaviour, with respect to yellow signal obedience or violation, is examined at a signalized intersection in Thessaloniki, Greece. The data, collected for the study purposes, include vehicles' speeds and distance from stop line when exposed to yellow light, gender and age group of drivers as well as reaction of Platoon leaders and first followers. Drivers were grouped into three categories, namely conservative, normal and aggressive, according to their behaviour at the intersection, the existence of a dilemma or option zone and their initial approaching speed. A binary choice model was also developed relating the probability of stopping at the STOP line or crossing it as a function of approach speed, distance from intersection, gender, age group and the existence or not of a dilemma zone. The findings of this research indicate that a large percentage of drivers facing the yellow signal are caught in a dilemma zone due to high approaching speeds and exercise an aggressive behaviour. The distribution of drivers into the three categories changes with differing assumptions pertaining to the factors affecting the calculation of safe stopping distance and critical crossing distance as well as speed thresholds for determining a priori aggressive behaviour. The research concludes that aggressive drivers represent a high percentage of all drivers and measures towards improving driving behaviour and/or reducing vehicles' speeds are required.     

The effect of distractions on the crash types of teenage drivers

Teenage drivers are overrepresented in crashes when compared to middle-aged drivers. Driver distraction is becoming a greater concern among this group as in-vehicle devices, opportunities for distractions, and teenage drivers' willingness to engage in these activities increase. The objective of this study was to determine how different distraction factors impact the crash types that are common among teenage drivers. A multinomial logit model was developed to predict the likelihood that a driver will be involved in one of three common crash types: an angular collision with a moving vehicle, a rear-end collision with a moving lead vehicle, and a collision with a fixed object. These crashes were evaluated in terms of four driver distraction categories: cognitive, cell phone related, in-vehicle, and passenger-related distractions. Different driver distractions have varying effects on teenage drivers' crash involvement. Teenage drivers that were distracted at an intersection by passengers or cognitively were more likely to be involved in rear-end and angular collisions when compared to fixed-object collisions. In-vehicle distractions resulted in a greater likelihood of a collision with a fixed object when compared to angular collisions. Cell phone distractions resulted in a higher likelihood of rear-end collision. The results from this study need to be evaluated with caution due to the limited number of distraction related cases available in the U.S. GES crash database. Implications for identifying and improving the reporting of driver distraction related factors are therefore discussed.     

矿用胶带输送机常用机械软启动装置

对矿用胶带输送机常用的几种机械软启动装置的结构、工作原理和主要性能特点进行了分析介绍，各类软启动装置存在较大差异，选用时，应根据实际情况进行技术经济综合分析比较后确定。     

Driver anger on the information superhighway: A content analysis of online complaints of offensive driver behaviour

In recent years, several websites have been developed allowing drivers to post their complaints about other motorists online. These websites allow drivers to describe the nature of the offensive behaviour and to identify the offending motorist by vehicle type, colour, and license plate number. Some websites also ask drivers to list the location where the event took place and the exact date and time of the offence. The current study was a content analysis of complaints posted to RoadRagers.com between 1999 and 2007 (N = 5624). The purpose of the study was to: (1) assess the research value of this novel data source; (2) demonstrate the value of content analysis to the study of driver behaviour; (3) further validate an existing coding scheme; (4) determine whether this new data source would replicate previous research findings regarding the most frequent types of driver complaints and temporal distribution of these reports; (5) provide recommendations for improved driver training and public safety initiatives based on these data. A coding scheme that was originally developed for an assessment of complaints submitted to the Ontario Provincial Police (OPP) ( Wickens et al., 2005) was revised to accommodate the new dataset. The inter-rater reliability of the revised coding scheme as applied to the website complaints was very good (kappa = .85). The most frequently reported improper driver behaviours were cutting/weaving, speeding, perceived displays of hostility, and tailgating. Reports were most frequent on weekdays and during the morning and afternoon rush hour. The current study replicated several findings from the analysis of reports to the OPP, but possible differences in the sample and data collection method also produced some differences in findings. The value of content analysis to driver behaviour research and of driver complaint websites as a data source was demonstrated. Implications for driver safety initiatives and future research will be discussed.     

Pregnant driver-associated motor vehicle crashes in North Carolina, 2001–2008

Background

Motor vehicle crashes are the leading cause of maternal injury-related mortality during pregnancy in the United States, yet pregnant women remain an understudied population in motor vehicle safety research.

Methods

We estimated the risk of being a pregnant driver in a crash among 878,546 pregnant women, 16–46 years, who reached the 20th week of pregnancy in North Carolina (NC) from 2001 to 2008. We also examined the circumstances surrounding the crash events. Pregnant drivers in crashes were identified by probabilistic linkage of live birth and fetal death records and state motor vehicle crash reports.

Results

During the 8-year study period, the estimated risk of being a driver in a crash was 12.6 per 1000 pregnant women. Pregnant women at highest risk of being drivers in serious crashes were 18–24 years old (4.5 per 1000; 95% confidence interval, CI,4.3, 4.7), non-Hispanic black (4.8 per 1000; 95% CI = 4.5, 5.1), had high school diplomas only (4.5 per 1000; 95% CI = 4.2, 4.7) or some college (4.1 per 1000; 95% CI = 3.9, 4.4), were unmarried (4.7 per 1000; 95% CI = 4.4, 4.9), or tobacco users (4.5 per 1000; 95% CI = 4.1, 5.0). A high proportion of crashes occurred between 20 and 27 weeks of pregnancy (45%) and a lower proportion of crashes involved unbelted pregnant drivers (1%) or airbag deployment (10%). Forty percent of crashes resulted in driver injuries.

Conclusions

NC has a relatively high pregnant driver crash risk among the four U.S. states that have linked vital records and crash reports to examine pregnancy-associated crashes. Crash risks were especially elevated among pregnant women who were young, non-Hispanic black, unmarried, or used tobacco. Additional research is needed to quantify pregnant women's driving frequency and patterns.     

0.18 μm CMOS单电流源模式LVDS驱动器设计

设计了一款单电流源模式低电压差分信号(LVDS)驱动器.采用反馈控制电路,以降低工艺、电压和温度变化引起的输出电平波动,电路稳定在规定的范围内.采用0.18 μm CMOS工艺设计,仿真结果表明,驱动器工作速率可以达到660 Mb/s,差分输出信号摆幅为320 mV.     

0.25W射频功率放大器

安华高的MGA-30489是一款0.25瓦高动态范围的驱动放大MMIC,它采用SOT-89的标准塑封。拥有极好的输入输出回损和良好的线性度。芯片很容易匹配,并获得最佳的功率和线性。     

GPU加速在集成成像的应用

针对在计算3D集成成像过程中耗时较多的问题,采用了一种新的硬件加速方法——GPU加速,分别在不同透镜数目和三维物体复杂度下,对CPU和GPU的运算时间进行对比。结果表明:计算复杂度大于数据拷贝时间时,GPU的整体加速效果明显,并且随着计算复杂度的提高,加速效果越来越显著。     

DAB接收机USB固件升级的实现

本文在自主开发的DAB接收机的基础上,提出一种通过USB接口实现接收机设备固件升级(DFU)的方法。当产品投入市场后可能会存在不足之处,通过DFU能达到对产品软件进行优化和修补的目的,也可为产品增加更多更新的功能,让用户获得更好的使用体验。经测试表明,本文提出的方法能可靠的对接收机产品进行固件升级。     

安森美半导体AC-DC非隔离高功率因数LED驱动方案

本文介绍了安森美半导体用于非隔离型AC-DC中低功率通用照明LED驱动器应用方案,给出试验样板的技术参数和测试结果。