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1.
Motor carrier safety is an important concern of shippers, carriers, policy makers, consignees, insurance providers, and the motoring public. One aspect of carrier safety that has garnered substantial attention is whether carriers making greater use of owner–operators are more or less safe vis‐à‐vis carriers making greater use of employee drivers. Currently, conflicting theoretical predictions exist regarding the direction of this relationship. In this article, we offer a reconciliation of the alternative theoretical predictions by developing a coherent theory that merges sociological rational choice theory and theory regarding motor carrier safety. We subject our theory to empirical testing by fitting a series of seemingly unrelated regression models to a vector of safety measures tracked as part of the Federal Motor Carrier Safety Administration's Compliance, Safety, and Accountability program. Our results are consistent with our proposed theory of owner—operator safety and provide meaningful theoretical and managerial implications and directions for future research.  相似文献   
2.
本文根据胶质含量测定试验方法的要求,以车用汽油中胶质含量(包括未洗胶质含量和溶剂洗胶质含量)测定为例,探讨了0.5单位数值修约、极限数值的表示和判定在胶质含量测定数据处理和结果判定中的应用。目的在于使车用汽油产品检测工作中在数据处理、报告和结果判定方面更加规范和统一。  相似文献   
3.
Previous research indicates that changes in housing wealth affect consumer spending on cars. We find that home equity extraction plays only a small role in this relationship. Consumers rarely use funds from equity extraction to purchase a car directly, even during the mid‐2000s’ housing boom; this finding holds across three nationally representative household surveys. We find in credit bureau data that equity extraction does lead to a statistically significant increase in auto loan originations, consistent with equity extraction easing borrowing constraints in the auto loan market. This channel, though, accounts for only a tiny share of overall car purchases.  相似文献   
4.
为了解四川省车用汽油质量安全现状,并为加强车用汽油质量安全监管提供依据,国家石油天然气产品质量监督检验中心在全省范围内采集3种标号共200个批次的车用汽油样品进行监测。结果表明:90号车用汽油质量安全的风险较高,93号车用汽油质量安全的风险较高,97号车用汽油质量存在风险,四川省流通领域的车用汽油质量现状并不乐观,消费者的用油安全存在一定风险。  相似文献   
5.
赵伟光 《价值工程》2014,(14):40-41
本设计利用凌阳SPCE061A单片机控制四相步进电机,完成智能小车前轮的连杆传动,带动前轮转向;并通过单片机控制功率放大电路,带动后轮共轴直流电机,完成正转倒转功能;其间的各种行进控制用语音识别来完成,包括前进,后退,停止,左转,右转。在智能车的前端装有两个光线传感器,可以通过对左右光线的变化识别是否将要碰撞前方障碍物,进而反馈到单片机进行转向控制,完成躲避障碍物的功能。  相似文献   
6.
王树生 《价值工程》2014,(19):52-53
简要介绍了应用于上海铁路局上海虹桥站动车段、武汉铁路局客运专线动车组检修基地上使用的CRH动车转向架检测输送线的组成、结构特点、主要技术参数及使用情况。  相似文献   
7.
Two questions facing motor carrier managers are (1) whether carriers should specialize in providing full truckload (TL) or less‐than‐truckload (LTL) services vis‐à‐vis offering mix of both and (2) whether this decision is contingent on carrier size. Yet, the literature provides little guidance because research to date has offered contradictory theoretical predictions and inconsistent empirical findings. Drawing on the theory of strategic purity and information processing theory, we explain why service specialization is likely to increase carriers' technical efficiency and why size will have a more pronounced effect on technical efficiency for carriers specializing in LTL services versus TL services. To test our theory, we assemble a panel data set from archival government sources regarding general freight motor carriers' provision of LTL and TL services. We measure carriers' technical efficiency using data envelopment analysis and test our hypotheses by fitting a series of panel data mixed‐effects models. Our results indicate that carriers are most technically efficient when they specialize in one service type. We also find that size positively affects technical efficiency but only for carriers specializing in LTL services; no returns to scale with regard to technical efficiency exist for carriers specializing in TL services.  相似文献   
8.
本文以对某钢铁企业2×360m2烧结机主抽风机电机高压变频调速系统调试为例,阐述了高压变频速系统的分类、特点和应用。  相似文献   
9.
This study aims to explore the motor insurance market's attitude towards usage‐based insurance (UBI), and thus its readiness for a launch in the near future. Data on client perception was collected using a structured questionnaire. On the basis of this, an initial selection of factors, other than income, that could influence the declared attitude of drivers was demonstrated showing that it is primarily dependent on certain demographic characteristics like their age, sex, or place of residence. A strong relationship was also demonstrated with respect to the intensity of the vehicle's use, to the amount of the insurance premium they have paid, and to the self‐assessment of the respondents' driving skills. Clients are likely to accept the concept of UBI once implemented, but that they are not ready yet to give up the traditionally used methods of premium calculation. Their attachment to discounts granted can be very strong in particular to the no‐claims bonus.  相似文献   
10.
吴国磊  罗毅  李玺尧 《价值工程》2014,(28):284-285
随着城市机动车保有量的迅速增加,机动车尾气污染已成为影响大气环境质量的一个重要污染源。本文系统监测了不同运行工况(高怠速、怠速)下机动车气体污染物排放水平,系统分析总结了CO和HC两种主要污染物变化规律,对控制机动车气体污染物水平,改善环境空气质量有重要理论和现实意义。  相似文献   
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