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61.

Problem

Motor-vehicle crashes are a leading cause of death in the United States. In the event of a crash, seat belts are highly effective in preventing serious injury and death.

Methods

Data from the 2006 Behavioral Risk Factor Surveillance System were used to calculate prevalence of seat belt use by state and territory and by type of state seat belt law (primary vs. secondary enforcement).

Results

In 2006, seat belt use among adults ranged from 58.3% to 91.9% in the states and territories. Seat belt use was 86.0% in states and territories with primary enforcement laws and 75.9% in states with secondary enforcement laws.

Discussion

Seat belt use continues to increase in the United States. Primary enforcement laws remain a more effective strategy than secondary enforcement laws in getting motor-vehicle occupants to wear their seat belts.  相似文献   
62.

Introduction

This article compares observed driving behavior in a city, a town, and a village.

Method

Unobtrusive observations were made at intersections in each residential type. Five violation types were observed: (a) not wearing a seat belt (seat belt violation); (b) not using a safety seat for a child (safety seat violation for children); (c) not using a speaker while speaking on the phone (on-phone violation); (d) failing to comply with a ‘give way’ sign (‘give way’ sign violation); and (e) stopping in an undesignated area (undesignated stop violation). It was expected that in accordance with the anonymity hypothesis that the bigger residential areas' rate of traffic violations would be higher. The effects of the residential type, drivers' gender, and age were assessed using the multiple regression model. The stepwise method of evaluation was employed. The model converged on step 3 (Adjusted R square = 0.039). Residential type and gender contributed significantly to the model. Results: Consistent with prior research, male drivers committed more violations than female drivers. Chi-square analyses were used to test the distribution of violations by the settlement types. Overall, more drivers committed violations in the two small residential areas than in the city, with 30% of city drivers, 43% of town drivers, and 51% of village drivers committing at least one violation (χ2 (2) = 37.65, p < 0.001). Moreover, in the town and the village, a combination of one or more violations was committed more often than in the city (χ2 (1) = 34.645, p < 0.001). Accordingly, more drivers committed violations in the two small settlements (48.4%) than in the city (30.6%). Possible explanations for the observed results were provided in the Discussion section.

Impact on Industry

The conclusions of this paper are that drivers in small villages tend to disobey traffic laws. Therefore, efforts have to be made in companies to take this issue in consideration while running fleets in companies located in small places far from the center.  相似文献   
63.
介绍了氧-乙炔火焰切割加工废钢铁产生的烟尘治理系统的设计和系统设备选型,重点介绍了烟尘捕集罩的设计和除尘器、电磁脉冲阀、风机的选型和PLC自动控制以及系统实际运行效果,为废钢铁加工企业治理污染提供一套简单、经济、实用的除尘系统作参考.  相似文献   
64.
介绍了一座80m烟囱由径向进气方式改为弧形切向进气的工程案例。列出了烟囱改造前后引风机运行一日的能耗数据,对比分析得出采用弧形烟道具有一定的节能效果,探讨了采用弧形烟道烟囱降低能耗的基本原因。  相似文献   
65.
如何合理确定村镇供水管网敷设方案,关系到整个供水系统的安全性和可靠性。通过生成树变化法,将环状管网转化成树状管网,确定供水管网中最短供水路线,再计算最短供水路线下的最低综合费用、供水系统的经济管径,以确定最优管道敷设方案。根据该方法对四川省某镇供水系统进行了设计。  相似文献   
66.
将产业结构演变的城市化响应系数作为衡量区域产业结构演变城市化响应强度的变量指标,运用变异系数和离差分析方法对陕西省产业结构演变的城市化响应进行类型划分,可划分为强响应区、中等响应区、弱响应区三种类型区;运用广义脉冲响应法对三种类型区分别进行产业结构演变城市化响应系数与各影响因素之间相关性的动态研究,探讨陕西省产业结构演变的城市化响应时至差异性。  相似文献   
67.
以糖、淀粉、蛋白质、纤维素培养基及菌株增殖倍数、菌株性能等为筛选方法,从牛粪低温堆肥中筛选不同原料重要功能菌并组成功能菌剂;以不同类别原料菌及单菌株发酵实验对升温机制进行研究。结果表明,芽孢杆菌、假单胞菌、纤维单胞菌及小孢霉菌等为重要功能菌;菌剂起温快,升温效果好,48 h堆体即由低温进入中温,5 d达到高温,腐熟时间可缩短至约17~18 d;糖功能菌升温效果最为显著,淀粉及蛋白质功能菌次之,纤维素功能菌升温能力较弱;菌株利用各种原料能力越强,增殖速度越快,对升温作用越大。各菌株充分利用基质各成分,紧密协同和促进,是低温堆体发酵升温的主要作用机制。  相似文献   
68.
王秀芳  刘国荣  朱珈 《环境技术》2008,26(1):22-24,45
本文简述电气领域如何评定测量不确定度过程,并结合CNAS T0346低温试验能力验证计划,识别和具体分析低温试验中各测量不确定度的来源,对各种影响因素进行评价,论述人、机、料、法、环、测各环节对测量结果的影响,给出了低温试验测量结果不确定度的评估过程。  相似文献   
69.

Problem

Motorized recreational vehicle (MRV)-related injuries can result in severe medical and financial consequences. The objective of this study was to describe the epidemiology, and clinical and financial impact of MRV-related injuries in Ohio.

Method

Probabilistically linked statewide Emergency Medical Services (EMS) and hospital (inpatient and emergency department) data for 2003 and 2004 were examined. Record pairs with a MRV-related E-code (E821-E823, E825) were included in this study.

Results

There were 2,893 patients with MRV-related injuries, who had linked EMS and hospital records, resulting in more than $15 million in hospital charges and 1,921 inpatient days of hospitalization. The male-to-female ratio was nearly 4:1, and 19% were younger than 16. Almost 82% of cases were not wearing a helmet; there was a trend of decreasing helmet use with increasing age. Mean (SE) inpatient hospital charges and length of stay (LOS) were $22,218 ($1,290) and 3.8 (0.2) days, respectively. The mean (SE) Injury Severity Score (ISS) for inpatients was 9.2 (0.4). Individuals injured on a street/highway were 3.20 times more likely to sustain an ISS ≥ 16 (95% CI: 1.03, 9.88; p = 0.044) and 3.05 times more likely to sustain a traumatic brain injury (TBI) (95% CI: 1.17, 7.94; p = 0.024) than those who were injured at a place designated for sport or recreation. Children aged 12 to 15 and young adults aged 16 to 25 were 2.47 and 2.14 times more likely, respectively, to sustain a TBI than adults aged 36 or older (aged 12 to 15: 95% CI: 1.13, 5.38; p = 0.024; aged 16 to 25: 95% CI: 1.26, 3.64; p = 0.005). Higher ISS was associated with both higher total charges (p < 0.001) and longer LOS (p < 0.001).

Discussion

This study demonstrates that MRV-related injuries are an important public health problem in Ohio, with a substantial clinical and financial impact.

Impact on Industry

Enactment and enforcement of statewide MRV safety legislation and training of MRV users offer valuable opportunities to prevent these costly injuries.  相似文献   
70.
影响马尾松毛虫虫灾发生类型因素的重要性分析   总被引:4,自引:1,他引:3  
运用列联表分析方法探讨了小班的林地起源、优势树种、地理、生长等因素对小班的马尾松毛虫虫灾发生类型的影响。分析结果表明:小班的海拔高度和坡度是决定小班的马尾松虫灾发生类型的关键因素。小班的优势种结构、平均树高及郁闭度对小班的马尾松毛虫虫灾发生类型也有较大的影响。图12表1参2  相似文献   
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