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501.
The concept of walkability refers to the extent to which a neighbourhood is walking-friendly. Several walkability indexes have been developed to quantify and evaluate the pedestrian environment. These indexes differ in terms of type of data, methods and goals. The indexes variables may present either uniform or distinct weights, defined by arbitrary, empirical or other diverse weighting methods. This paper pursues the determination of a weighted walkability index, constructed on the basis of the relative importance of their attributes. Weights were determined by the application of the Fuzzy Analytic Hierarchy Process (FAHP), a robust multi-criteria method which considers the experts’ uncertainty in decision making. Moreover, FAHP weights were compared with the attribute weights obtained from other simpler methods, and a chi-square test for homogeneity was computed to compare the obtained values. The three most important walkability attributes were: Public Security, Traffic Safety and Pavement Quality, similar results to the ones found in the literature. The application to a case study in the city of Porto Alegre, Brazil, allowed categorizing the studied neighbourhoods and to analyse the effect of changes on attributes in walkability. 相似文献
502.
The existing literature on urban transportation planning in China focuses primarily on large cities and neglects small cities. This paper aims to fill part of the knowledge gap by examining travel mode choice in Changting, a small city that has been experiencing fast spatial expansion and growing transportation problems. Using survey data collected from 1470 respondents on weekdays and weekends, the study investigates the relationship between mode choice and individuals’ socio-economic characteristics, trip characteristics, attitudes, and home and workplace built environments. While more than 35 percent of survey respondents are car owners, walk, bicycle, e-bike, and motorcycle still account for over 85 percent of trips made during peak hours. E-bike and motorcycle are the dominant means of travel on weekdays, but many people shift to walking and cycling on weekends, making non-motorized and semi-motorized travel especially important for non-commuting trips. Results of multinomial logistic regression show that: (1) job-housing balance might exert different effects on mode choice in different types of urban areas; (2) negative attitude towards e-bike and motorcycle is associated with more walking and cycling; and (3) land use diversity of workplace is related to commuting mode choice on weekdays, while land use diversities of both residential and activity places do not significantly affect mode choice on weekends. Our findings imply that planning and design for small cities needs to differentiate land use and transportation strategies in various types of areas, and to launch outreach programs to shift people’s mode choice from motorized travel to walking and cycling. 相似文献
503.
从我国证券投资基金发展现状出发,通过对证券投资基金投资者资产补偿和保险机制国际通行做法的分析,对我国证券投资者资产补偿和保险机制发展缓慢的原因进行了分析,提出了具体的措施。 相似文献
504.
505.
广东省中小企业自主创新的环境、问题及对策 总被引:1,自引:0,他引:1
索德拉图 《广东交通职业技术学院学报》2009,8(2):52-54
文章在对广东省中小企业自主创新环境、问题进行总体分析的基础上,针对广东省中小企业自主创新中的困难和问题.探索地方政府在促进中小企业自主创新中的作用、责任以及政府促进中小企业自主创新的财税政策措施。借鉴国外成功经验,在财政政策上,政府对中小企业自主创新进行直接投资、财政补贴、政府出资设立中小企业自主创新专项基金、建立科技开发准备金制度;在税收政策上,优化政府的税收政策设计、允许中小企业实行加速折旧、制定有利于中小企业自主创新的税收减免政策等。 相似文献
506.
507.
Theory suggests that profit maximizing firms have an incentive to incorporate cost-effective technologies into their products. However, simple net present value calculations comparing upfront costs of fuel-saving technologies to future savings suggest this is not always the case. This puzzle is commonly referred to as the “energy efficiency paradox.” A growing number of empirical studies examine why households may under-invest in energy efficiency. Fewer studies examine similar undervaluation by businesses. We explore investment decisions within the heavy-duty trucking sector for fuel-saving technologies via focus groups and interviews to gain insight into what factors might explain apparent underinvestment in fuel-saving technologies. We find some evidence that market failures related to lack of information about technology performance and network externalities contribute to slow adoption of some technologies. However, information about new technologies for tractors seems to generate limited spillovers. There is also some evidence of split incentives between owners and drivers, though companies have invested in a variety of technologies and approaches in an attempt to address these effects. Other factors important in trucking investment decisions that are not classic market failures include tradeoffs between fuel economy and other valued truck attributes, as well as uncertainty and risk associated with new technologies if decision-makers are loss averse. 相似文献
508.
进入“十五”计划以后,工程项目固定资产投资进入新一轮发展高潮,几乎每一个领域都有大量基本建设项目,给工程造价咨询业带来了“如何最有效控制项目投资”的课题。该文着重从现场投资监理的角度,讨论从招标到竣工结算等重要环节的工程投资监理方法。 相似文献
509.
西部高速公路工程环境保护技术研究 总被引:2,自引:1,他引:2
阐述了西部高速公路建设带来的环境问题及保护方法,针对西部地区的区域特点,通过常吉高速公路实例,研究了高速公路施工阶段和营运期间的自然环境保护技术,从而给出了解决高速公路建设与自然环境保护之间的可行保护措施。 相似文献
510.
高速列车的动态环境及其技术的根本特点 总被引:7,自引:1,他引:7
讨论了高速列车所处的动态环境。指出高速列车与普通列车的根本不同在于列车所处的动态环境发生了质的变化,由机械、电气作用为主,变为以气动作用为主。正是由于这一巨大变化,才产生了一系列高速列车技术的特点。例如,由于需要特大牵引功率来克服地表稠密大气所产生的阻力,高速列车必须放弃机车牵引,采用动车组模式;对高速列车必须进行“噪声设计”,才能分别按环保要求决定高速通道不同区段的最高限制速度。本文根据上述观点得出一些不同于通常所理解的关于地面高速交通的结论。比如:指出磁浮列车只有在低速下运行,才能凸显其低噪声的优点,高速度并不是它的特长。本文还进一步指出,地面开敞式高速交通,最高速度不宜高于400 km/h,超过这一限速必须采用真空管道高速交通。 相似文献