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21.
Transportation - A fully separated bicycle network from vehicular traffic is not realistic even for the most bicycle-friendly cities. Thus, all around the world urban cycling entails switching...  相似文献   
22.
Although considerable progress has recently been made in the evolution of marine traffic procedures in coastal and waterway areas, mariners are finding difficulty in coping with the diverse traffic schemes that have so far been devised. This paper is a plea for international and logical marine traffic management, so that ships can operate safely and efficiently within a framework of the proliferating offshore zonal legislation that we are now witnessing.  相似文献   
23.
Under the 1997 Oceans Act, Fisheries and Oceans Canada (DFO) is required to lead and facilitate the development of integrated management plans for Canada's oceans. One of the integrated management projects is the Eastern Scotian Shelf Integrated Management Initiative (ESSIM), through which DFO is working with a range of stakeholders to develop and implement an integrated ocean management plan for the eastern Scotian Shelf. As part of this Initiative, DFO has undertaken a program to develop a set of objectives and related indicators for ocean management. This includes the development of a framework, objectives, and indicators for human use of the resource including the social, economic, and institutional (governance) components of ocean management, areas that have received little attention internationally. This article provides some background to ESSIM and human uses of the resources of the eastern Scotian Shelf; briefly reviews objectives-based management and human use objectives internationally; outlines the process undertaken to develop the Human Use Objectives Framework; presents the resultant objectives and indicators that were developed; and highlights some of the lessons learned and challenges for their implementation.  相似文献   
24.
In a car-free city centre car traffic is limited by an area-wide ban to its functionally necessary share. This usually includes delivery and service vehicles and residents' cars. The lock-out of unnecessary car traffic must not be an isolated measure, but part of a pulland-push approach. The most important supporting measure concerns the provision of attractive public transport services. Case studies from Bologna, Lubeck, Aachen, York, and Nuremburg are reported.  相似文献   
25.
控股大众的现实意义2005年9月保时捷宣布收购大众的18.5%股权。从而宣布两家公司的关系回到了费迪南德先生开发大众甲壳虫车的30年代。围绕Ferdinand Piech(费迪南德·保时捷的孙子)的角色问题,这一控股行动倍受股东和金融机构的质疑。  相似文献   
26.
The transport sector has been identified as a significant contributor to greenhouse gas emissions. As part of its emissions reduction strategy, the United Kingdom Government is demonstrating support for new vehicle technologies, paying attention, in particular, to electric vehicles.Cluster analysis was applied to Census data in order to identify potential alternative fuel vehicle drivers in the city of Birmingham, United Kingdom. The clustering was undertaken based on characteristics of age, income, car ownership, home ownership, socio-economic status and education. Almost 60% of areas that most closely fitted the profile of an alternative fuel vehicle driver were found to be located across four wards furthest from Birmingham city centre, while the areas with the poorest fit were located towards the centre of Birmingham. The paper demonstrates how Census data can be used in the initial stages of identifying potential early adopters of alternative vehicle drivers. It also shows how such research can provide scope for infrastructure planning and policy development for local and national authorities, while also providing useful marketing information to car manufacturers.  相似文献   
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介绍了在钢桥连接系采用空心截面杆件时,连接系与主梁的连接问题中,偏心连接板有效长度系数的分析和确定.有效长度系数对于这种连接的设计起关键作用.在分析过程中,运用了NASTRAN有限元分析平台对实际问题进行了建模计算,并对结果进行了比较分析.从结果中,我们发现,连接板尺寸的变化可以得出不同的破坏荷载,从而推导出不同的有效长度系数.使用较长的连接板可以得出较小的有效长度系数.板厚的增大使有效长度系数明显增大.通过本文的几个模型分析结果,我们发现,有效长度系数取值在1.0~2.0之间.  相似文献   
29.
Virtually all marine conservation planning and management models in place or proposed have in common the need for improved scientific rigor in identifying and characterizing the marine habitats and processes encompassed. An emerging central theme in the last few years has been the concept of representativeness, or representative systems of marine protected areas (MPAs). Representativeness and similar terms are used in two distinct senses in current literature, leading to considerable confusion. Definitions of these terms as they are currently used are provided. The habitat classification and mapping needed to incorporate considerations of representativeness into MPA planning must logically be carried out at the same scale at which management occurs. Management of highly protected areas is found to occur almost exclusively at local scales or finer, independent of the reservation model or philosophy employed. Current techniques for cost-effective surveying of marine areas are discussed. The emerging field of remote videography, in some cases linked with acoustic discrimination sensors, can provide quantitative data on real biological distributions. Such data lend themselves well to robust multivariate analysis in deriving habitat maps at scales relevant to managers, as a basis for assessing and planning for representation in MPA design.  相似文献   
30.
Abstract

The location as well as pace of marina development is a major issue in current coastal zone management. The supply and demand for marinas providing certain services in specific locations are growing and must be met. At the same time the environmental integrity of the coastal zone must be maintained against the many possible impacts of marina development. Compounding these problems from the view of both the developer and coastal zone manager is the absence of necessary data and accepted methodologies for estimating future supply needs for marine berthing. This paper describes a multi‐focii approach to the establishment of an information base and marina supply projections for the Mississippi Gulf Coast. Data on existing marina types, services, and facilities are obtained via fieldwork; future marina slip supply needs are estimated using a combination of several techniques and data sources. The study serves two purposes. First, it initiates the basis for improved management of marina development on Mississippi's Gulf Coast. Second, on a more theoretical level, it stimulates research toward developing and validating supply and demand projection techniques for marinas.  相似文献   
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