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21.
Centralized, top-down fisheries management models based on biological stock-recruitment have, at best, achieved limited success when adapted to Third World fisheries. Comanagement, a resource management approach oriented towards resource users and their communities, has been proposed as an alternative strategy for managing Third World fisheries. We examine the initial success and subsequent problems of one such collaborative coastal zone management project on St. Lucia's leeward coast. Factors that must be considered in the development, implementation, and maintenance of coastal comanagement systems operating in the contexts of tropical marine ecosystems in developing nations are identified and discussed.  相似文献   
22.
The success of any coastal zone management policy is dependent on, among other things, effective legislation and its enforcement. This article examines some possible legal constraints on the implementation of an integrated coastal zone management policy in Ireland. An introduction to the existing legal framework is provided, and the inconsistencies and ambiguities related, in particular, to jurisdiction and area of responsibility are highlighted. In particular the effect of land ownership and property rights on coastal zone management are examined with reference to two popular resort beaches in County Donegal, Ireland. While a revision of the relevant legislation is desirable, it is probably unrealistic; however, powers are available to the various institutions involved in coastal management that are currently unused. These are reviewed and their potential to improve coastal zone management is discussed.  相似文献   
23.
Scientific knowledge is central to “good” governance of coastal spaces: developing methods through which the complexities of the coastal zone can be understood by stakeholders to improve the sustainable management of coastal systems. Enhancing our knowledge of the range of processes that shape coastal spaces and define the total behavioural environment of the system remains a primary challenge for the coastal research community. However, this article raises the argument that current approaches to Integrated Coastal Zone Management (ICZM)—the preferred governing framework for the coastal environment, do not give sufficient emphasis to this fundamental need. Improving the basic scientific knowledge that underpins policymaking at the coast is argued to be urgently needed. Issues such as that of developing a communality of the purpose and approach between stakeholders within the coastal zone (through conflict resolution and access to information, for example) seem to claim the rights of the integrated management research agenda. However, the very nature of ICZM as “worthwhile coastal management” requires that integrated management represents more than a governing framework. Successful integration in coastal management must also be underpinned by knowledge of the integrated behavior of the system. Science has an increasingly marginalized position within ICZM and as a result geographers, contributing knowledge of the patterns and processes of the human and environmental landscapes, are also becoming a disappearing breed in integrated coastal management.  相似文献   
24.
区域控制器(Zone Controller,ZC)边界切换场景是城市轨道交通列车控制系统的重要场景,切换过程中移交ZC、接管ZC和车载子系统之间要进行频繁的信息交互,因而对其安全性和实时性有更严苛的要求。根据ZC子系统特点,将MSC半形式化方法作为切入点,结合时间自动机理论,建立ZC切换场景的MSC模型和时间自动机网络模型,用于ZC切换场景功能和受限活性的安全验证。结果表明:ZC边界切换控制功能满足系统安全性和受限活性的规范要求。因此此种建模验证方法是可行的,可以将其应用于列控系统其他场景的建模与验证过程中。  相似文献   
25.
Irritablebowelsyndrome(IBS)isacommon functionalgastrointestinaldisorderinpopulations.RecentstudieshaveshownthatpersistentIBSsymp tomsdevelopedinbetween7%and31%ofsubjects afterinfectiousgastroenteritisandtransientinflam mationenteritis[1].Thisassociationis…  相似文献   
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The main purpose of this paper is to develop an efficient method to design traffic analysis zones (TAZs), which is necessary for implementing a planning process with Geographic Information System (GIS) for Transportation (GIS‐T), using statistical spatial data analyses and GIS technology. The major roles of GIS in this method are: (1) to produce basic spatial units (BSUs) with topological data structure; (2) to integrate various procedures during the TAZ generation including computer program routines; and (3) to visualize the output of each TAZ generation. One of the most significant reasons for obtaining well‐defined TAZs is the fact that they are defined at the outset of transportation demand modeling, used from trip generation to trip assignment, and will ultimately affect transportation policy decisions.

Toward obtaining well‐defined TAZs, this paper concentrates on two important constraints: homogeneity and contiguity. Iterative partitioning technique is adopted to promote the optimum homogeneity of generated TAZs, while a contiguity checking algorithm is developed to ensure contiguous TAZs are generated by the iterative partitioning technique.  相似文献   
28.
鄱阳湖生态经济区文化软实力建设是提升鄱阳湖生态经济区整体实力和竞争力的必然要求,是指基于已有文化资源,通过采取相应举措,增强其内在的凝聚力、生命力、创新力和外在的感召力、吸引力、影响力。丰富的文化资源是文化软实力建设的基础。鄱阳湖生态经济区文化资源转化为文化软实力还面临内在凝聚力不强、对外传播力不大等诸多困境,提炼核心价值观、加强传播力度、推进资源开发、吸纳优质人才、强化合作交流、构建长效机制是破解困境之策。  相似文献   
29.
Beach management and coastal management are interwoven and scale-dependent activities in Australia. Present coastal policies are broad and designed for large, national, and statewide scales. They specify ecologically sustainable development as the overarching goal for coastal management and provide the context for beach management. On smaller scales, an approach focusing on the reduction of geomorphic hazards as the basis of beach management was established by the Coastline Hazard Policy, with nonhazard aspects of beach management such as ecological, economic, and social concerns assuming secondary importance. Although beach management can occur effectively under these coastal management arrangements, better guidance is required to make this process as effective and efficient as possible. This guidance - the policy framework - could be better developed for beach management and better integrated with existing coastal management arrangements. While this policy development is not strictly necessary to achieve positive outcomes from beach management, it is necessary to effectively guide implementation of the existing broad coastal policies. Effective goals for beach management are yet to be thought out and clearly articulated in Australia. A good start would be to couple the present goals of ecologically sustainable development and hazards reduction into a coherent goal for beach management. A specific policy for beaches should be developed given the importance of beaches in Australia.  相似文献   
30.
Q235钢焊接熔合区在混合菌共同作用下的腐蚀行为   总被引:1,自引:0,他引:1  
通过观察腐蚀形貌,测量极化曲线和阻抗谱,研究了Q235钢熔合区在SRB和V.natriegens共同作用下的腐蚀行为。研究表明,熔合区的腐蚀程度,单一菌溶液中,SRB大于V.natriegens,混合菌溶液大于单一菌;混合菌溶液中SRB和V.natriegens表现出协同作用,加速试样的腐蚀;试样的耐腐蚀性能,熔合区小于焊缝区小于母材区。  相似文献   
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