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1.
This paper analyzes the effects of cell phone usage and economic freedom on motor vehicle death rates by estimating regression models on data for three years across 38 countries. The models incorporate a representative set of motor vehicle fatality determinants. Results indicate that cell phone use has a statistically significant nonlinear impact on highway death rates and that economic freedom does not appear to have an effect.  相似文献   
2.
文中首先分析了公路客运交通枢纽选址问题的研究思路.然后从客运枢纽为了达到方便客户、优化路网、减少投资等综合交通最优化的角度建立了教学模型,并给出了用遗传算法求解的程序流程图.最后通过某城市的客运枢纽规划实例,表明此理论型布局能够满足人们的出行需求,显示了该方法的科学性和可行性.  相似文献   
3.
支持向量机(Support Vector Machine,SVM)是建立在统计学习理论和结构风险最小化准则基础上的机器学习方法,该方法可以较好的解决以往很多学习方法的小样本、高维数、非线性和局部最小点等实际问题.本文利用支持向量机(SVM)回归理论和方法,建立基于核函数主成分支持向量机(Kernel Principal Component Analysis-Support Vector Machine,KPCA-SVM)回归模型,并用2000-2008年杭州市公路客运量为样本进行了预测,结果表明,KPCA-SVM模型具有较高的预测精度和可靠性,是一种有效的公路客运量预测方法.  相似文献   
4.
The concept of “inducing growth” is typically considered an adverse consequence of a project on the land use system. In certain instances, however, the desire to induce growth and foster land use change is a focus of land use policy. Such is the example of the Appalachian Highway Development System (AHDS) program initiated by the Appalachian Regional Commission (ARC) during the late 1960s. With the goal of providing highway infrastructure to improve assess to a geographically isolated and historically impoverished region, the ADHS has added nearly 3000 miles of highway to the Appalachian landscape. The degree to which highway investment has contributed to regional growth remains a controversial point and tractable methods to quickly assess landscape change given a project of this magnitude are elusive. In this paper a portion of the AHDS trending through southern Ohio is examined using data acquired from the Landsat series of satellites. Beginning with a pre-highway condition in 1976, a 26 year time horizon, concluding in 2002, was analyzed based on a post-classification change detection methodology. Results of this investigation revealed slight, yet significant, levels of urban expansion within a 10 km corridor along the path of AHDS Corridor D/State Route 32. Beyond this buffer zone the land use system evidenced more stability, suggesting that as distance increased from Corridor D/State Route 32, reduced accessibility also reduced the attractiveness of land for urban uses. Relating these results back to the infrastructure investment policies of the ARC demonstrates that growth did result from the construction of Corridor D and supports previous findings that land development based on highway construction is extremely time-sensitive.  相似文献   
5.
我国公路工程施工质量管理浅析   总被引:1,自引:0,他引:1  
我国每年的公路工程投资巨大,公路工程投资的质量管理是一个非常棘手的问题.文章根据公路工程建设的特点,分析了当前我国公路工程建设质量管理的问题,提出了解决的思路.  相似文献   
6.
The state of the nation’s infrastructure is the subject of widespread discussion and comment because it is thought to include many deteriorating and unsafe bridges. Ever since the terrorist attacks of 9/11, there has been increasing concern over the extent to which an attack on infrastructure could result in serious economic disruption. This research develops a model to analyze the economic consequences of an attack on a major element of the highway network. We add a freight network to a national multiregional economic impact model and make freight traffic flows endogenous. The use of a sub-national interstate model recognizes that most infrastructure planning is at the state level and most political leaders’ interest is local. We base our approach on the National Interstate Economic Model (NIEMO) and refer to an elaboration that we name Transportation network and the National Interstate Economic Model (TransNIEMO). The new model enables us to study the state-specific and industry-specific economic impacts of some significant changes in the nature of highway freight movements. We tested the model for selected freight movements in and out of California. The results are entirely plausible and encourage us to elaborate and test the model for hypothetical disruptions of freight traffic throughout the US.  相似文献   
7.
The study investigated trends in traffic crashes with fatal and non-fatal injuries in Arkhangelsk, Russia in 2005–2010. Data were obtained from the road police. Negative binomial regression with time regressor was used to investigate trends in monthly incidence rates (IRs) of crashes, fatalities, and non-fatal injuries. During the six-year period, the police registered 4955 crashes with fatal and non-fatal injuries, which resulted in 217 fatalities and 5964 non-fatal injury cases. The IR of crashes with fatal and non-fatal injuries per total population showed no evident change, while the IR per increasing total number of motor vehicles decreased on average by 0.6% per month. Pedestrian crashes constituted 51.8% of studied crashes, and pedestrians constituted 54.6% of fatalities and 44.5% of non-fatal injuries. The IRs of pedestrian crashes and non-fatal pedestrian injuries per total population decreased on average by 0.3% per month, and these were the major trends in the data.  相似文献   
8.
This fictional prototype explores two of the future's major societal challenges: the delivery of healthcare to an increasingly ageing society; and the policing of a society, in which digital surveillance may predominate. It contrasts the author's vision of what life could be like in the United Kingdom in a decade's time (just as he contemplates retirement) with the simpler values of the 1980s, when he began his postgraduate career. The lyrics of the poignant 1982 Bruce Springsteen song, “Highway Patrolman” are used to bridge the epochs1. The prototype relocates the two main ‘middle-America’ characters, brothers Joe and Frank Roberts, in London in the year 2025. Much has already changed politically and socially in ‘Western societies’ in the intervening period up to 2012, driven by the inexorable advances of technology. As further scientific advances drive us to an anticipated paradigm change,2 one can only speculate on how society will advance, posing serious ethical dilemmas. Many of the changes will be positive. However, the story explores the potential negative consequences to the ageing population, in what appears to be a successful economy. Although somewhat pessimistic in outlook, a hopeful conclusion is that the ‘ties that bind’ will still predominate.  相似文献   
9.
The highway logo signing program has existed for over 20 years. Since its inception, most motorists have become accustomed to relying on these blue signs to provide information on services available at each highway exit. However, there is little, if any, literature that examines the program as an advertising source, and no formal literature that addresses the signing program from the perspective of the independent business owner. This paper provides service business owners with information about the highway logo signing program, and is directed toward independent owners who are considering the signing program as an advertising source. A five step process is described that owners can follow to first determine if the venue is viable, and then if the investment is value-added for them.  相似文献   
10.
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