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161.
162.
Floriano C. M. Pires Luis F. Assis Cassiano M. Souza 《Maritime Policy and Management》2005,32(3):209-226
The Brazilian ship financing system has some unique features. The funds made available to finance the construction and acquisition of ships are sourced from a tax on import and cabotage freight, payable by the shippers. For Brazilian flagged ships, a portion of the tax generated can be used for the payment of loan instalments. This paper analyses the impact of the tax on the economy as a whole, and discusses the distribution of the tax burden between the shipowner and the shipper, taking into account the maritime transport demand elasticities in Brazil. The paper also analyses the effectiveness of the financing system in reducing the capital cost to shipowner, and the distortion effects produced by the utilization of the tax in loan repayments. The conclusion is that there are important distortions that may threaten the recovery of the maritime industry in Brazil. 相似文献
163.
164.
Sandford F. Borins 《Transportation Research Part B: Methodological》1982,16(1):17-29
A simulation model was used to show the impacts of non-optimal pricing and investment timing policies for a major airport and an urban expressway. It was found that: the losses of economic surplus due to non-optimal pricing and investment policies were relatively small (less than 1% of the net present value of economic surplus for optimal pricing and investment), that marginal cost pricing covers the capital cost of all but the first increment of capacity, that higher user fees will permit the facilities to break even with relatively small losses of economic surplus, that marginal cost pricing has some effect relative to existing pricing policies in delaying the dates new capacity is required and achieving better capacity utilization, and that the shape of the cost function has a substantial impact on the amount of capacity required. 相似文献
165.
EXPRESSION CLONING OF A PROTECTIVE LEISHMANIA ANTIGEN 总被引:5,自引:0,他引:5
郑时春 《西安交通大学学报(英文版)》1995,(2)
EXPRESSIONCLONINGOFAPROTECTIVELEISHMANIAANTIGENE.Mougneau,F.Altars,A.E.Wakil,ZhengShichun;T.Coppola,Z.Wang,R.Waldmann,R.M.Loc... 相似文献
166.
167.
F. J. J. Cadwallader 《Maritime Policy and Management》2013,40(5):253-254
168.
In 1991, the Aquaculture Department of the Southeast Asian Fisheries Development Center launched a community-based fishery resources management project on Malalison Island, in central Philippines, to help conserve the country's marine resources and to help the fisherfolk rise above their poverty. The eight-year project integrated various disciplines in biology, economics, sociology, public administration, and engineering in its study of fishery resources and fishing communities and in evolving intervention strategies for resource conservation and management, and for community development. The project's most important accomplishment was the inculcation among the fisherfolk of the importance of resource conservation and management. The most important lesson learned was that an enlightened and empowered fisherfolk could be effective managers and responsible users of fishery resources. 相似文献
169.
比较了不同结构径向转向型与普通2轴转向架间的动力不.折重点是直线稳定性,曲线轮轨横向力和轮轨磨耗指标等参数。其结果表明,所研究的径向转向架结构在一般应用范围内,没有比普通转向架起到更好的作用。但在特殊运行条件下和某些应用形式中,某些径向转向架比普通转向架更具优势。 相似文献
170.
刘贵 《变流技术与电力牵引》2007,(2):52-57
燃料电池(FC)通常输出直流低压.受工作条件影响,其输出电压不稳定,且动态响应明显慢于瞬变负载的要求,因此在许多应用中,燃料电池发电机必须与负载以及其它可能的能源/电源相连接.基于这些原因,燃料电池堆输出功率、蓄电池/超级电容器的输入/输出功率必须经过电力电子变换器进行调节.阐述了与燃料电池功率输出调节有关的主要问题,尤其考虑了在2种最重要的应用场合(微分布式发电或联产发电和运输系统)下,与其相连的.电力电子变流器的特定要求.主要讨论了燃料电池功率调节专用的DC/DC变换器的基本电路结构,着重考虑PEMFC技术. 相似文献