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41.
Three design problems are discussed in this article. First, it is shown that the network design problem with congestion reduces to an all-or nothing traffic assignment problem under some assumptions on the congestion function and the investment cost function. Second, the land use design problem is formulated as an extension of the Koopmans-Beckmann problem and a heuristic is proposed to solve this problem. Third, it is shown that the seemingly more complex problem of designing jointly a land-use plan and a transportation network reduces to a pure land-use design problem. All that is needed to solve the joint optimization problem is a shortest path algorithm and a heuristic to solve the land use design problem. Computational experience is reported for each algorithm.  相似文献   
42.
43.
Abstract

Over 90 percent of British Columbia's annual log harvest enters into complex water‐based systems of transportation, storage, and handling. These systems have considerable impacts on a wide range of coastal resources and uses. A number of site‐specific conflicts have arisen between forestry and preexisting or emerging values including fisheries, mariculture, recreational boating, and harbor redevelopment. Specific data on the impacts leading to conflict are often fragmentary. However, concerns about highly valued and fragile areas‐particularly estuariesalong with industrial concerns regarding log losses and handling efficiency, have prompted changes in log handling. These include moves to dryland sorting, log bundling, and a redistribution of forestry activities in estuaries to accommodate other values. Conflict adjustments and responses have in the past been largely ad hoc and attempted in a jurisdictional vacuum concerning control of coastal management. A more inclusive strategy is now slowly emerging, which involves the coordinated participation of federal, provincial, and industrial interests.  相似文献   
44.
The Coastal Zone Management Effectiveness Study was undertaken between 1995 and 1997 to determine how well state coastal management programs in the United States were implementing five of the core objectives of the U.S. Coastal Zone Management Act (CZMA). The five core objectives studied were: (1) protection of estuaries and coastal wetlands; (2) protection of beaches, dunes, bluffs and rocky shores; (3) provision of public access to the shore; (4) revitalization of urban waterfronts; and (5) accommodation of seaport development (as an illustration of the policy to give priority to coastal-dependent uses). Separate articles in this issue of Coastal Management report the findings of the five studies, each dealing with one of the core objectives. Each of the articles assesses issue importance, processes and tools used, and the limited outcome data available for that objective. This article provides an overview of the purposes of the study, the methodology used, the summary findings of each study, and overall conclusions and recommendations of the study team. State coastal programs are found to be effective in addressing the five CZMA objectives examined, but this conclusion is based on very limited information about program outcomes. A more definitive conclusion will require better outcome information. Coastal managers in the United States have not agreed upon indicators of success, which severely inhibits systematic and sustained collection of outcome information. A national outcome monitoring and performance evaluation system is recommended to address these deficiencies and allow better determinations of program effectiveness in the future.  相似文献   
45.
4~18周之雄性自发高血压大鼠(SHR)与正常血压(WKY)鼠各分为5个年龄组。乙醚麻醉下测取有关心功能指标,并以短暂的主动脉阻闭所得到的左室发展压峰值(pDevP,由左室收缩压减去左室舒张末压获得)作为左室最大压力产生能力的指标。实验结果显示:①各年龄组SHR之动脉收缩压、舒张压、平均动脉压、左室收缩压均高于同龄组WKY鼠(P<0.05)。SHR之上述指标随年龄增长而增高。②各年龄组SHR之pDevP均高于同龄组WKY鼠(P<0.05)。SHR之pDevP随年龄增长而增大。  相似文献   
46.
To explain walking propensity or frequency, empirical studies have generally used two sets of explanatory variables, namely, socio-demographic variables and built environment variables. They have generally shown that both socio-demographic characteristics and built environment characteristics are associated with walking propensity. We examine the traditional walkability variables that encompass density, mix of uses, and network connectivity in New Jersey, using a statewide sample including an oversample of Jersey City. We estimate a two-stage least squares model using a conditional mixed process that combines an ordered probit model of walking frequency in the second stage based on a truncated regression of car ownership in the first stage. Our results show that built environment variables have some small effects, mainly from better network connectivity associated with increased walking frequency. One of our key findings is that built environment features also work indirectly via how they influence car ownership. In general, we find sufficient evidence that suggests fewer cars are owned in areas with more walkable built environment features. The other key variable that we control for is whether a household owns a dog. This also proved to be strongly associated with walking suggesting that dog ownership is a necessary control variable to understand the frequency of walking.  相似文献   
47.
坦白讲,实际上这是一篇软文,是一家美国的小规模汽车公司Local Motors的软文。很显然,远在大洋彼岸的我们完全与这个汽车公司所在的市场没有任何关系,也就不可能因为刊登这个软文获得任何商业上的好处。但我还是认为Local Motors的传奇创立者的传奇故事,以及他对待汽车的全新角度将会让你看到一种全新的汽车制造模式,或者说关于汽车制造的思考方式。"我想象的微型工厂里不仅能制造汽车,还会是汽车结束生命的地方。"  相似文献   
48.
汽车设计师盖瑞·麦戈文(GerryMcGovern)的家坐落在无忧无虑的英国乡间,他对自己的这栋现代派宅子相当得意,特地邀我们上门拍摄他的最新杰作、路虎Evoque。车子和宅子本身一样,都停泊在不怎么稳当的斜坡上,两者如面包和果酱一般亲密无间。  相似文献   
49.
Abstract

Marine and coastal zone policy represents a collaboration of people managing and people managed. This paper takes a holistic stance in suggesting that marine communities are viewed properly as networks of focused interest groups, policymakers, professionals, and publics. The interplay between culture and marine and coastal policy is appropriately one topic of applied social research. Seven ethnographic studies in this domain are introduced in this theme issue and help us to understand sociocultural processes and institutions bearing on marine affairs.  相似文献   
50.
Abstract

The European Union (EU) promotes gradual lifting of restrictions on foreign hauliers involved in domestic road transport of goods (cabotage), and a major deregulation was scheduled in 2014. Due to complaints from several member states facing competition from new EU-countries with lower labour costs, this process was postponed until 2015. An important aspect related to such a deregulatory reform includes potential consequences for transport safety and accident risk factors. The main aims of the current paper are therefore to examine the potential transport safety outcomes of increasing internationalization of domestic road haulage, and to examine potential accident risk factors of foreign hauliers. This is done by reviewing the research literature. This paper shows that the heavy goods vehicle (HGV) accident risk varies with a factor of up to 10 in European countries, and that the accident risk of foreign HGVs is approximately two times higher than that of domestic HGVs in the studied European countries. The paper points to several risk factors and concludes that better data on accident risk and risk factors must be gathered in order to enable European authorities to correctly analyse and respond to this important traffic safety challenge.  相似文献   
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