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11.
王凡  左志  王涛 《交通标准化》2014,(15):25-31
将出行者按照时间价值(VOT)和地域划分为不同群体,在一个简单路网上建立交通网络模型,分析拥挤收费的公平性影响.研究模拟居民的多种不同出行选择,分析了实施拥挤收费对两处居民各类人群在出行方式分担、行程时间以及交通可达性等方面的影响.研究发现,对于始发地居民,引入拥挤收费能够降低其行程时间,提高可达性;而对于周边道路沿途的居民,若周边道路通行能力不高,适当的拥挤收费会提高可达性,若周边道路通行能力较好,拥挤收费则会小幅度的减少其交通可达性.  相似文献   
12.
扇区复杂度作为管制员工作负荷和动态空域配置的重要参考依据,需要事先准确地对其 进行评估。本文针对有监督复杂度数据集存在的小样本问题,提出基于条件生成对抗网络的扇 区复杂度评估框架。首先,构建交通流量、航空器性能和潜在冲突这3类复杂度指标,并结合主观 复杂度等级得到标定样本;其次,利用条件生成对抗网络设计有标记样本生成算法,获得增广数 据集;最后,分别采用逻辑回归、支持向量机和随机森林算法建立复杂度评估模型。以中南区域 扇区为例,从定性和定量的视角验证生成样本的有效性,并在多种训练集配置下对比各模型评估 结果。研究结果表明:条件生成对抗网络在200次迭代后逐步收敛至稳定;生成样本与真实样本 的绝大多数指标在均值上的相对误差小于5%,在标准差上的相对误差大于5%;在多分类评价指 标下,增广数据集对3种模型整体评估精度分别提升11.77%、11.04%和8.34%。本文提出的评估 框架可以在有限数据条件下提高样本多样性,是解决扇区复杂度评估问题的一种有效方法。  相似文献   
13.
本文以2005-2006年度房地产行业上市公司作为样本,研究股权融资成本与信息披露质量之间的关系。在对变量的描述和样本检验的基础上,我们可以得出结论,即信息披露质量越高,股权融资成本越低。最后,本文通过实验研究,提出了一系列降低股权融资成本的政策建议。  相似文献   
14.
城市公共交通是一种特殊的公共资源,影响各个社会群体获得其他发展资源的机会.目前,中国仍然缺乏评价城市公共交通资源空间配置社会公平绩效的有效方法.基于社会公平理念,以2010年上海市中心城区为例,提出轨道交通网络分布的社会公平绩效评价和分析方法.首先,采用基尼系数和洛伦兹曲线,对轨道交通网络分布和常住人口分布的空间匹配进行社会公平绩效的总体评价.其次,采用区位熵的方法进行社会公平绩效的空间分析.研究表明:人均享有轨道交通网络资源水平的空间差异由多种原因造成,这也显示出在城市轨道交通网络分布中应用社会公平概念的复杂性;在土地使用规划中强调混合功能和职住平衡是提高轨道交通网络分布的社会公平绩效的重要策略.最后指出,城市轨道交通网络分布的社会公平绩效评价方法可用于同一城市的历时性比较和不同城市的共时性比较.  相似文献   
15.
Air pollution and road traffic noise are considered to be the two most important nuisances that could negatively affect the quality of life. A prolonged exposure to high concentrations of these pollutants could conduct to various health problems. Studies in environmental equity have often considered these nuisances individually whenever it comes from the same source. The main objective of this paper is to determine if the 15 years of age, those aged 65 and over, visible minorities and low income individuals located in a portion of the Island of Montreal are overrepresented in city blocks characterized by having among the highest levels of transportation-related air pollutants (i.e., ambient concentrations of NO2 and road traffic noise in decibels (dB(A)). The results show that low-income individuals and, to a lesser extent, visible minorities, are significantly overrepresented in city blocks characterized by the higher levels of NO2 and road traffic noise in dB(A). Multinomial logistic regression analysis confirms these results, and also shows that young people under 15 years are under-represented in the most polluted areas. However, contrary to the previous bivariate results, people aged 65 and over are negatively and significantly associated with the likelihood of their living in a city block located in an advantaged area after controlling for the independent effects of the other explanatory variables. Moreover, visible minorities are significantly overrepresented in advantaged areas. Considering the observed results, some solutions are identified to reduce road traffic noise and air pollution in the city blocks localized near major traffic arteries.  相似文献   
16.
The goal of this study is to develop and apply a new method for assessing social equity impacts of distance-based public transit fares. Shifting to a distance-based fare structure can disproportionately favor or penalize different subgroups of a population based on variations in settlement patterns, travel needs, and most importantly, transit use. According to federal law, such disparities must be evaluated by the transit agency, but the area-based techniques identified by the Federal Transit Authority for assessing discrimination fail to account for disparities in distances travelled by transit users. This means that transit agencies currently lack guidelines for assessing the social equity impacts of replacing flat fare with distance-based fare structures. Our solution is to incorporate a joint ordinal/continuous model of trip generation and distance travelled into a GIS Decision Support System. The system enables a transit planner to visualize and compare distance travelled and transit-cost maps for different population profiles and fare structures. We apply the method to a case study in the Wasatch Front, Utah, where the Utah Transit Authority is exploring a switch to a distance-based fare structure. The analysis reveals that overall distance-based fares benefit low-income, elderly, and non-white populations. However, the effect is geographically uneven, and may be negative for members of these groups living on the urban fringe.  相似文献   
17.
Social equity is increasingly becoming an important objective in transport planning and project evaluation. This paper provides a framework and an empirical investigation in the Greater Toronto and Hamilton Area (GTHA) examining the links between public transit accessibility and the risks of social exclusion, simply understood as the suppressed ability to conduct daily activities at normal levels. Specifically, we use a large-sample travel survey to present a new transport-geography concept termed participation deserts, neighbourhood-level clusters of lower than expected activity participation. We then use multivariate models to estimate where, and for whom, improvements in transit accessibility will effectively increase activity participation and reduce risks of transport-related social exclusion. Our results show that neighbourhoods with high concentrations of low-income and zero-car households located outside of major transit corridors are the most sensitive to having improvements in accessibility increase daily activity participation rates. We contend that transit investments providing better connections to these neighbourhoods would have the greatest benefit in terms of alleviating existing inequalities and reducing the risks of social exclusion. The ability for transport investments to liberate suppressed activity participation is not currently being predicted or valued in existing transport evaluation methodologies, but there is great potential in doing so in order to capture the social equity benefits associated with increasing transit accessibility.  相似文献   
18.
In this paper, we represent a systematic review of stated preference studies examining the extent to which cycle infrastructure preferences vary by gender and by age. A search of online, English-language academic and policy literature was followed by a three-stage screening process to identify relevant studies. We found 54 studies that investigated whether preferences for cycle infrastructure varied by gender and/or by age. Forty-four of these studies considered the extent of separation from motor traffic. The remainder of the studies covered diverse topics, including preferred winter maintenance methods and attitudes to cycle track lighting. We found that women reported stronger preferences than men for greater separation from motor traffic. There was weaker evidence of stronger preferences among older people. Differences in preferences were quantitative rather than qualitative; that is, preferences for separated infrastructure were stronger in some groups than in others, but no group preferred integration with motor traffic. Thus, in low-cycling countries seeking to increase cycling, this evidence suggests focusing on the stronger preferences of under-represented groups as a necessary element of universal design for cycling.  相似文献   
19.
我国铁路投资公平性问题和投融资体制改革的研究   总被引:3,自引:1,他引:2  
研究目的:铁路的运力不足、线路负荷过重已经成为制约我国经济发展的一道“瓶颈”,铁路布局的地域差异性使得西部地区过于单薄的铁路网无法满足西部大开发和区域经济协调发展的需求,如何加快并保障我国铁路事业均衡、快速、可持续发展已引起人们的普遍关注。研究方法:从投融资改革的角度探讨了铁路发展问题,同时引入了地区公平性的原理。研究结论:本文重点分析了我国铁路产业投融资市场化的可行模式和政府引导的多主体投资形式,并提出了国家在土地、税收和财政补贴等多方面支持西部地区铁路建设的倾斜性政策和措施。  相似文献   
20.
中国铁路建设投资公司成立以来,作为合资铁路中铁道部出资人代表,不断强化责任意识,按照“资产监管、资本经营”的发展方针,精心组织,推进项目的引资融资,依法组建项目公司,规范运作,强化项目公司建设和项目建设的投资控制,创新项目的运营管理模式,提高运营效益。在工作中,坚持工程建设与公司建设、投资监管与项目融资、出资人自身建设与项目建设并重,在实践中取得了一定成绩。  相似文献   
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