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61.
This article reports on an integrated modeling exercise, conducted on behalf of the US Federal Highway Administration, on the potential for frequent automated transit shuttles (‘community transit’), in conjunction with improvements to the walking and cycling environment, to overcome the last-mile problem of regional rail transit and thereby divert travelers away from car use. A set of interlocking investigations was undertaken, including development of urban visualizations, distribution of a home-based survey supporting a stated-preference model of mode choice, development of an agent-based model, and alignment of the mode-choice and agent-based models. The investigations were designed to produce best-case estimates of the impact of community transit and ancillary improvements in reducing car use. The models in combination suggested significant potential to divert drivers, especially in areas that were relatively transit-poor to begin with.  相似文献   
62.

This article examines the sociocultural, economic, and environmental causes of the decline of the artisanal fisheries in the rocky coast of Cape Creus (NW Mediterranean) over the past decades. The changes that have occurred over time have favored trawlers, purse-seiners, shellfish fisheries, and tourism activities, to the detriment of artisanal fisheries. This article shows that the establishment of a marine reserve in 1998 could not reverse the observed decline in the artisanal fisheries. This raises the necessity of implementing a fishery management plan integrated into a coastal management plan, which should accompany the habitat protection. These plans could assist in the maintenance and the sustainable development of the artisanal fishing sector in Cape Creus as well as in other Mediterranean coastal areas where artisanal fisheries are also declining.  相似文献   
63.
Book review     
Modern Transport Geography. Edited by R. S. Hoyle and R. D. Knowles on behalf of the Transport Geography Study Group of the Institute of British Geographers. (London: Belhaven, 1992.) [Pp.276.] £15–99 (Paperback). ISBN 1 852 93158 2; £45·00 (Hardback). ISBN 1 852 93157 4.  相似文献   
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简述了制动噪声的影响因素,分析了制动噪声产生机理以及解决方法。  相似文献   
67.
如何提高双面胶带在外饰零件粘接效果的研究,在工程设计和材料学研究中一直是空白,通过对粘贴的设计、工艺、过程和结果评估几个方面进行分析,探讨提高双面胶带在外饰零件粘接效果的方案和措施。  相似文献   
68.
利用多体动力学技术和联合仿真的方法及半主动开关控制和改进型开关控制中的时滞,对车辆动力学性能的影响进行了仿真分析.结果表明:无时滞理想状态下,半主动控制对车辆横向动力学性能的控制效果明显,且运行速度越高控制效果越好;时滞对车辆横向动力学性能的影响较大,但并非随着时滞的增大而逐渐恶化,而是呈波浪形起伏,当时滞处于100~200 ms和400~500ms范围时,半主动控制效果最差,甚至失效;考虑时滞后,开关控制效果优于其改进型,这与没有考虑时滞因素时结论相反,证实了时滞分析的必要.  相似文献   
69.
Chile has been attempting to establish a Management Area (MA) system that melds the use of marine protected areas with marine tenure. The process has brought to the fore the competing interests of various user groups: artisanal fishermen, marine science professionals, government managers, tourist developers, and the Navy. We explore the core relationships among fishermen and the ecologists and biologists whose work is essential for establishing and maintaining a MA. The MA system's creation and implementation raise the key question of whether a marine tenure system can work under the conditions imposed by the Chilean government. There is a need to recognize and reconcile contradictions in a government management model that strives simultaneously to be a conservation zone and a financially profitable co-management zone. This article examines the MA management system's fault lines in the context of Chile's political economy, and the intimate interaction of management with fishermen's cultural survival strategies.  相似文献   
70.
In areas like household production and travel choice, time assigned to the different activities plays a key role in addition to consumption as the main variables in utility within the consumer behaviour framework. However, a comprehensive conceptual structure to understand the technological relations between goods consumption and the assignment of time to activities is still lacking. In this paper the problem is reviewed and all possible relations between goods and time are re-formulated. Two general functions are defined and proposed to account for all these relations, forming a new taxonomy for the technical constraints. The resulting consumer behaviour model is used to obtain general expressions for both the value of saving time in constrained activities like travel, and the value of leisure.  相似文献   
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