The Illinois .08 law. An evaluation

Lowering state blood alcohol concentration (BAC) limits to 0.08, though controversial, has been supported by most evaluation studies to date. The Illinois .08 BAC law implemented in 1997 provided a unique opportunity to evaluate the effect of the law without the simultaneous passage of an administrative license revocation (ALR) law, which has clouded some previous evaluations of the .08 laws. The proportion of all drinking drivers in fatal crashes was compared before versus after implementing the .08 law using time-series analysis to evaluate 12 years of fatal crash data for Illinois and five bordering states. The results showed that the proportion of drinking drivers in fatal crashes decreased by 14% in Illinois and increased by 3% in bordering states. The proportion of drinking drivers in fatal crashes in Illinois, though increasing since 1995, was sharply reduced after passage of the .08 law in 1997, saving more than 100 lives in 1998 and 1999 than it would have without the .08 law.     

Forfeiture programs in California: why so few?

PROBLEM: It is estimated that at least 75% of suspended or revoked drivers continue to drive illegally. In states like California, there are also a substantial and growing number of people who drive without ever having been licensed. Some states, such as Ohio and California, have enacted vehicle impoundment and forfeiture programs as sanctions to reduce these offenses. Published evaluations indicate that vehicle impoundment laws reduce recidivism and crash rates. However, vehicle forfeiture programs have been less successful, mostly because of low levels of enforcement. METHOD: Police officers and district attorneys from 17 jurisdictions were interviewed by phone or in person to determine current enforcement levels and impediments to more aggressive application of statutory authority. RESULTS AND DISCUSSION: The survey found that most California jurisdictions are enforcing vehicle impoundments for first-time offenders. However, very few jurisdictions were enforcing the vehicle forfeiture law for repeat offenders. Among the reasons for not enforcing the vehicle forfeiture law was a perception that it was too time-consuming and/or not a priority among prosecutors. However, a number of authorities indicated that the simple vehicle impoundment procedure is often functionally equivalent to forfeiture because many drivers fail to retrieve the vehicle at the end of the impoundment period. IMPACT ON INDUSTRY: Vehicle impoundment programs are effective mechanisms in deterring illicit driving, and states should be encouraged to initiate vehicle impoundment laws. States could achieve even greater safety benefits if vehicle forfeiture sanctions were extensively used for repeat offenders. However, based on California's experience, the incremental benefits of vehicle forfeiture (over vehicle impoundment) may not be very great.     

Using a driving simulator to identify older drivers at inflated risk of motor vehicle crashes

PROBLEM: To develop appropriate assessment criteria to measure the performance of older drivers using an interactive PC-based driving simulator, and to determine which measures were associated with the occurrence of motor-vehicle crash. METHOD: One hundred and twenty-nine older drivers residing in a metropolitan city volunteered to participate in this retrospective cohort study. Using the driving simulator, appropriate driving tasks were devised to test the older drivers, whose performances were assessed by 10 reliable assessment criteria. Logistic regression analysis was then undertaken to determine those criteria that influence the self-reported crash outcome. RESULTS: As expected, driving skill of older drivers was found to decline with age. Over 60% of the sample participants reported having at least one motor-vehicle crash during the past year. Adjusting for age in a logistic regression analysis, the cognitive abilities associated with the crash occurrence were working memory, decision making under pressure of time, and confidence in driving at high speed. SUMMARY: The findings of this retrospective study indicated those individuals at inflated risk of vehicle crashes could be identified using the PC-based interactive driving simulator. Prospective studies need to be undertaken to determine whether the driving simulator can predict future crash events. IMPACT ON INDUSTRY: This study demonstrated an economical driving simulator approach to screen out problematic or unsafe older drivers before a more detailed but expensive road test is considered.     

山岳型旅游地旅游城镇化动力机制研究——以九华山为例

旅游城镇化是指发展旅游业的地区为了给旅游者提供交通、游览、食宿、娱乐、购物等一系列服务，使生产、提供这些商品和服务的行业与居民大量在此聚集，逐渐形成具有明显职能特色的城镇的过程。分析旅游城镇化现象产生的动力机制是旅游城镇化研究的重要内容。在实地调研的基础上，以九华山为例，分析了山岳型旅游地旅游城镇化现象产生和发展的内外多维动力系统，并结合九华山独特的佛教旅游地特征，有针对性地分析了九华山旅游城镇化发展的特点。     

不同城市化速度地区建设用地演变驱动力比较研究

以深圳和武汉为例,选择与建设用地相关性大的10项社会经济指标,采用简单的逐步回归方法对城市化速度存在较大差异的2个城市建设用地演变驱动力进行了比较分析,对2个城市驱动力的共性和差异给出了合理解释,可增强对城市化过程中建设用地演变机理的动态理解,为抑制建设用地的过快增长提供参考。     

应用车载测试系统研究轻型机动车在实际道路上的排放特征

采用一套车载排放测试系统,对深圳市7辆具有代表性的轻型车辆进了实际道路排放测试.根据测试结果,分析了机动车运行工况对排放的影响,比较了基于油耗和行驶里程的排放因子,并计算了各测试车辆的平均排放因子.结果表明,深圳市轻型机动车加速和减速运行模式共占整个运行时间的66.7%和行驶里程的80.3%,对各种污染物的贡献率达74.6%～79.2%.并且加速模式下的排放水平明显高于其他运行模式;基于油耗的排放因子受车速的影响较小,可以避免因机动车运行工况不同所带来的排放差异,从宏观尺度更为合理地预测机动车污染物排放量;车辆技术水平对排放影响很大,化油器车的C0、HC和NOx排放因子分别是欧Ⅲ车的19.9～20.5、5.6～26.1和1.8～2.0倍;我国在进行轻型车排放测试时使用ECE EUDC工况,不能反映我国城市实际道路行驶工况下的机动车排放水平.     

长江上游植被覆盖的时空分异季节变化及其驱动因子研究

以GIMMS/NDVl为基础,结合气候与人类活动数据,研究了1982～2003年间长江上游植被覆盖季节变化的空间分布.结果表明,近22年来,长江上游春季、夏季植被覆盖呈增加趋势,以春季最显著;秋季、冬季植被覆盖呈降低趋势,以秋季降低最显著.春季、夏季降雨与气温的同步增加,致使植被覆盖增加;秋季降雨减少,以及气温的增加导致植被覆盖降低;另外,作物播种面积的增加是春季、夏季植被覆盖增加,秋季、冬季植被覆盖减少的重要原因.春季→夏季→秋季→冬季NDVI增加的区域在窄问上大致呈现低纬度向高纬度转移的趋势.春季、夏季所有植被类型的NDVI均有增加趋势;而秋季所有植被类型的NDVI均降低;冬季植被除针叶林的NDVI略有增长外,其余植被类型的NDVI均降低.     

基于遥感影像的1992—2002年昆明市城区扩张及驱动力分析

以TM＼ETM＋遥感影像为数据源,利用ERDAS软件经过几何校正、图像增强等处理,得到比较清晰的昆明市的遥感影像,再对其进行非监督分类,得到昆明市土地利用分类图,在土地利用分类图的基础上进行二值化处理。提取出1992年和2002昆明市主城区图,并把二者叠加,生成1992年-2002年昆明市城区城市扩张图。通过计算得出：1992年面积约为193．16km^2,同样可计算出2002年面积为258．09km^2,以年平均增长率为3．36％的速度迅速扩展,建成区扩展弹性系数为0．85,处于相对协调期,但要略低于合理值。扩展方向主要为以老城区为核心向东南、西南和东北三个方向呈“星形”扩展。通过综合分析影响昆明市扩展的各种因素发现：自然因素、交通因素是城市扩展的条件和基础,社会经济是城市扩展的内在推动力,规划、政策等对扩展起引导作用。     

基于PEMS的柴油公交车排放测试分析

使用车载尾气检测技术PEMS对一辆在用国Ⅲ柴油公交车进行了实际公交线路运行时的气态污染物排放测试,统计得出了车辆运行速度、加速度、气态污染物排放速率、排放因子特性。分析结果表明公交车平均速度为18 km/h,96.9%的速度点落在0~40 km/h的区间段,99%的加速度点落在-1.5~1.5 m/s2的区间段。随着车速的增加,排气污染物排放速率增大,其中NOX排放速率增大显著。车速增大,污染物排放因子降低;低于30 km/h时,车速增大,排放因子降低显著,高于30 km/h时,排放因子随车速增大变化变缓。排放因子受排放速率和车速共同影响。污染物排放速率随加速度增大而增大,加速时的排放速率显著高于减速时的排放速率。研究结果说明,提高车辆运行速度、减少急加速,可以有效降低公交车尾气排放。     

机动车车载尾气检测技术研究综述

车载尾气检测技术的出现和发展为机动车尾气的相关研究提供了一种较为准确、便捷、实时反映城市路网排放的测试方法。本文详细介绍了车载尾气检测技术的发展历程和原理,综述了该技术在行驶周期开发、尾气排放特性和规律研究、建立机动车尾气排放数据库和建立城市路网排放清单等领域的应用现状,并通过比较该技术在国内、外的应用差距,提出了在绿色交通领域充分利用该技术进行机动车污染评价与控制的合理建议。