汽车EPS系统的行车工况补偿控制策略

针对汽车在常见转向工况时转向的操纵性和安全性不足问题,提出将常见工况补偿控制策略融合到汽车EPS助力控制中,将汽车速度、汽车质量、方向盘左右晃动考虑在内,设计了高速避让、低速满载、颠簸路面3种补偿控制策略;并理论分析加入高速避让、低速满载、颠簸路面3种补偿策略后,方向盘、齿条位移和汽车横摆角速度增减值的变化;最后,通过搭建汽车EPS系统模型和二自由度汽车模型进行仿真验证。仿真结果表明,采用补偿控制策略后,汽车在高速、低速大重量及于凹凸不平的路面行驶时,助力电机目标电流的获取与汽车行驶的内外环境紧密相连,且可随行车条件的改变而适时改变,使汽车EPS系统具有了更好的操纵性和安全性。     

Differential protective effects of motorcycle helmets against head injury

Background: Although numerous observational studies have demonstrated a protective effect of motorcycle helmets against head injury, the degree of protection against specific head injury types remains unclear. Experimental biomechanics studies involving cadavers, animals, and computer models have established that head injuries have varying etiologies. This retrospective cross-sectional study compared helmet protection against skull fracture, cerebral contusion, intracranial hemorrhage, and cerebral concussion in a consecutive series of motorcycle operators involved in recent traffic crashes in Kentucky.

Methods: Police collision reports linked to hospital inpatient and emergency department (ED) claims were analyzed for the period 2008 to 2012. Motorcycle operators with known helmet use who were not killed at the crash scene were included in the study. Helmet use was ascertained from the police report. Skull fracture, cerebral contusion, intracranial hemorrhage, and cerebral concussion were identified from International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes on the claims records. The relative risks of each type of head injury for helmeted versus unprotected operators were estimated using generalized estimating equations.

Results: Helmets offer substantial protection against skull fracture (relative risk [RR] = 0.31, 95% confidence interval [CI], 0.23, 0.34), cerebral contusion (RR = 0.29, 95% CI, 0.16, 0.53), and intracranial hemorrhage (RR = 0.47, 95% CI, 0.35, 0.63). The findings pertaining to uncomplicated concussion (RR = 0.80, 95% CI, 0.64, 1.01) were inconclusive. A modest protective effect (20% risk reduction) was suggested by the relative risk estimate, but the 95% confidence interval included the null value.

Conclusions: Motorcycle helmets were associated with a 69% reduction in skull fractures, 71% reduction in cerebral contusion, and 53% reduction in intracranial hemorrhage. This study finds that current motorcycle helmets do not protect equally against all types of head injury. Efforts to improve rotational acceleration management in motorcycle helmets should be considered.     

The influence of personal protection equipment,occupant body size,and restraint system on the frontal impact responses of Hybrid III ATDs in tactical vehicles

Objective: Although advanced restraint systems, such as seat belt pretensioners and load limiters, can provide improved occupant protection in crashes, such technologies are currently not utilized in military vehicles. The design and use of military vehicles presents unique challenges to occupant safety—including differences in compartment geometry and occupant clothing and gear—that make direct application of optimal civilian restraint systems to military vehicles inappropriate. For military vehicle environments, finite element (FE) modeling can be used to assess various configurations of restraint systems and determine the optimal configuration that minimizes injury risk to the occupant. The models must, however, be validated against physical tests before implementation. The objective of this study was therefore to provide the data necessary for FE model validation by conducting sled tests using anthropomorphic test devices (ATDs). A secondary objective of this test series was to examine the influence of occupant body size (5th percentile female, 50th percentile male, and 95th percentile male), military gear (helmet/vest/tactical assault panels), seat belt type (3-point and 5-point), and advanced seat belt technologies (pretensioner and load limiter) on occupant kinematics and injury risk in frontal crashes.

Methods: In total, 20 frontal sled tests were conducted using a custom sled buck that was reconfigurable to represent both the driver and passenger compartments of a light tactical military vehicle. Tests were performed at a delta-V of 30 mph and a peak acceleration of 25 g. The sled tests used the Hybrid III 5th percentile female, 50th percentile male, and 95th percentile male ATDs outfitted with standard combat boots and advanced combat helmets. In some tests, the ATDs were outfitted with additional military gear, which included an improved outer tactical vest (IOTV), IOTV and squad automatic weapon (SAW) gunner with a tactical assault panel (TAP), or IOTV and rifleman with TAP. ATD kinematics and injury outcomes were determined for each test.

Results: Maximum excursions were generally greater in the 95th percentile male compared to the 50th percentile male ATD and in ATDs wearing TAP compared to ATDs without TAP. Pretensioners and load limiters were effective in decreasing excursions and injury measures, even when the ATD was outfitted in military gear.

Conclusions: ATD injury response and kinematics are influenced by the size of the ATD, military gear, and restraint system. This study has provided important data for validating FE models of military occupants, which can be used for design optimization of military vehicle restraint systems.     

Examining motor vehicle crash involvement and readiness to change on drinking and driving behaviors among injured emergency department patients

Objective: To measure the effect of motor vehicle crash (MVC) involvement and readiness to change drinking and driving behaviors on subsequent driving and drinking behaviors among injured emergency department (ED) patients who use alcohol at harmful levels.

Methods: This was a secondary analysis of a randomized controlled trial of injured ED patients who screened positive for harmful alcohol use, who at recruitment reported driving in the past 12 months and received at least one of the intended intervention sessions (brief behavioral intervention versus attention placebo control; N = 407). Outcome variables were as follows: (1) change in 6 impaired driving behaviors and (2) report of MVCs and traffic violations in the 12 months following recruitment; predictor variables were as follows: (1) treatment assignment, (2) MVC involvement at recruitment, and (3) baseline readiness to change alcohol use and drinking and driving.

Results: Modeling of change in the 6 impaired driving variables indicated that neither the recruitment visits being MVC related nor baseline readiness to change alcohol use and drinking and driving behaviors predicted greater changes in impaired driving over time. Baseline reports of past moving traffic violations and the ED visit being MVC related predicted a greater likelihood of each behavior at 12 months following study recruitment.

Conclusions: This study and others have demonstrated that ED patients with harmful alcohol use are willing to engage in behavioral interventions directed at changing risky behaviors. However, this study did not demonstrate that patients considered having the potential to be more engaged with the intervention because their ED visit was MVC related and/or they had expressed intent to change their risky alcohol use and drinking and driving behaviors were more likely to change these risky behaviors.     

移动除臭装置对填埋场作业面膜下臭气去除试验研究

采用移动除臭装置对填埋场作业面夜间覆膜后产生的臭气进行净化试验研究。结果表明,移动除臭装置对臭气中H2S和NH3平均去除率分别为52.7%,41.3%;臭气浓度平均去除率为97.4%;甲硫醇及甲硫醚的去除率分别为99.9%,100%。温度、气体停留时间是影响除臭效果的主要因素。     

Impact of Georgia's teenage and adult driver responsibility act: 15-year follow-up

Objective: This study was designed to investigate the 15-year impact of Georgia's graduated drivers' licensing (GDL) law, the “Teenage and Adult Driver Responsibility Act” (TADRA), on fatality crashes among young drivers.

Methods: Fatality Analysis Reporting System (FARS) data for Georgia and Census denominators were used to determine fatal crash rates (FCRs) of drivers ages 16 through 19 who passed through the Georgia GDL system during the 5.5 years prior to through 15.5 years after TADRA's implementation. FCRs of younger drivers were compared to those of drivers ages 20–54 and 55–75 and compared by gender. Attention was given to speeding- and alcohol-related crashes, 2 foci of TADRA.

Results: The decline in FCRs has been maintained and even increased through 15.5 years after passage of the law. Extending the curfew and further limiting passengers (passed in 2001) and driver's education and supervised driving requirements (added in 2007) may have contributed. The greatest declines were among 16- and 17-year-olds; most of the gains were among male drivers. The changes were greatest for alcohol- and speeding-related crashes. Those 18 and 19 years old did not demonstrate an increase in FCR over the period studied.

Conclusion: Georgia's graduated licensing law, TADRA, has maintained and in some instances increased in effectiveness over the 15.5 years since its inception. Though national research suggests that GDL laws are associated with increased crash rates among 18- to 19-year-old drivers, this has not occurred in Georgia; 18- and 19-year-olds demonstrated no change or reductions in FCR over the 20.5-year period evaluated. Declines were greatest for those driving behaviors targeted by the law.     

天津市在用汽车遥感检测分析研究

遥测法是对在用车污染情况进行监督管理的高效、便捷的新技术,利用天津市遥测法对路上行驶的在用车的监测数据,分析了各项污染指标间的关系、同一辆车检测数据的重复性、对在用车的控制效果、不同控制方案下遥测法检测限值,并提出了遥测法检测数据的精度要求。     

佛山市南海城区环境空气中铅污染现状分析研究

为了解佛山市南海城区环境空气中铅污染现状,在南海城区中心设置空气质量监测点,采用重量法和电感耦合等离子体质谱法分别对空气颗粒物及不同粒径颗粒物的铅含量进行定量分析,测定结果为:TSP、PM10、PM2.5平均浓度分别是150 ug/m3、99 ug/m3、67 ug/m3,其中铅平均浓度分别是214 ng/m3、175 ng/m3、156 ng/m3.结论为:南海城区环境空气中的铅浓度达到国家环境空气质量二级标准,铅污染水平处于珠江三角洲的中游;大气中的铅主要分布在PM2.5中,机动车尾气是其主要来源.