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201.
In Brazil, the explosion of informal transport activity during the past decade has had profound effects on formal public transport
systems and is a source of great controversy in the urban transportation sector. A variety of policies have been proposed
to manage the growth of the sector. This study seeks to understand how proposed policies will impact the users of these systems.
A corridor in Rio de Janeiro with substantial informal activity was used as a case study. Measures of welfare changes in a
discrete choice framework were used to estimate proposed policies’ impacts on users. Eleven candidate policies were evaluated,
ranging from the eradication of the informal modes and investment in formal modes, to the legalization of the informal modes.
Benefits were compared with costs and the distribution of benefits across income classes was explored. Net benefits from some
policies were found to be substantial. Legalizing the informal sector was found to benefit users slightly but further investments
in the sector are probably inefficient. Users benefited most from improvements in formal mass transit modes, at roughly 100–200
dollars per commuter per year. Finally, policies to foster a competitive environment for the delivery of both informal and
formal services were shown to benefit users about 100 dollars per commuter per year. Together, the regulation of the informal
sector and investments in the formal sector serve to reinforce the movement towards competitive concessions for services and
help reduce the impacts of cartelization and costly in-road competition.
相似文献
Ronaldo BalassianoEmail: |
202.
Lidia P. Kostyniuk 《Transportation》2009,36(6):641-642
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船舶减摇方式介绍及发展趋势 总被引:2,自引:0,他引:2
针对船舶的减摇问题,综述了船舶减摇的几种方法,分析了船舶主要减摇装置舭龙骨、减摇鳍、减摇水舱、减摇舵的优缺点,指出了存在的技术难题,并展望了有价值的研究方向。 相似文献
205.
在乘用车前期设计阶段,为让儿童保护的安全性能得到控制和优化,以某乘用车根据国家安全法规要求进行儿童座椅拉拽台架试验时,ISOFIX固定装置出现焊点从车身上拉脱失效为例,基于焊点热影响区损伤的焊点失效准则和钣金断裂失效准则,运用有限元分析对其进行虚拟评估和结构改进,有限元分析与试验结果吻合良好.改进结构通过了儿童座椅拉拽... 相似文献
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This paper studies the fault diagnosis of singular stochastic systems. The probability distribution of output is measured
by probability density functions (PDFs), which are modeled by a square root B-spline expansion. An adaptive nonlinear observer
is proposed to estimate the size of the fault occurring in systems. Furthermore, the linear matrix inequality (LMI) approach
is applied to establish sufficient conditions for the existence of the observer. Finally, the simulation results are given
to indicate the method for diagnosing the fault. 相似文献
210.
Michael Ekow Manuel 《WMU Journal of Maritime Affairs》2017,16(3):473-483
Traditional seafarer training has always focused on the acquisition and use of practical skills. The prevailing view is that, while this approach addresses a degree of cognitive skills, it focuses on and gives much more emphasis to the acquisition of hands-on practical skills for the performance of specific tasks. On the other hand, academic education has been seen to be much more focused on the development of in-depth analytical and critical thinking skills; cognitive skills that are less reliant on hands-on task-oriented training, but stress critical reading and discussion. The global trend in maritime education and training is increasingly to link an essentially vocational education that provides specific and restricted competence outcomes with more general or deeper academic components leading to an academic qualification. This trend has led to some dilemmas for curriculum development, for training legislation in a global industry, and for achieving desired learning outcomes in a professional setting (in the shipping industry). This paper discusses some of the challenges arising from this trend and the opportunities the trend offers. 相似文献