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城市生态系统内部各组分之间存在着错综复杂的关系,任一组分的变化会对其他组分产生不同程度的影响.快速的城市化进程带来了一系列影响城市可持续发展的问题.若想从根本上消除这些可持续发展隐患,需要采用"耦合"方法.本文明晰了"耦合"的3种应用情景及相应定义表述,同时对城市耦合理论发展脉络进行梳理,分别从物理耦合视角及政策效果耦合视角进行能-水-食物-土地-气候变化(EWFLC)五系统两两分析总结.从物理耦合视角解读发现,目前的耦合研究大多集中在城市尺度,并且主要针对两个系统之间的直接耦合关系,间接耦合关系研究相对缺乏,两系统的关联多会对社会和经济产生积极影响.从政策效果耦合视角来看,目前针对五系统的政策多面向直接解决目标系统问题,政策实施的中间目标大多可量化,且政策效果评估大多含有多个指标.在此基础上,本文提出了可同时结合物理耦合及政策效益耦合的城市EWFLC五系统分析框架,旨在帮助城市开展政策遴选,实现城市可持续发展.  相似文献   

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Climate change: the science and the policy   总被引:7,自引:3,他引:4  
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Patients with end-stage heart failure have a trajectory of illness characterized by an overall gradual decline in function punctuated by periods of symptom exacerbation followed by a return nearly to their baseline. These exacerbations are not predictable. Death may come suddenly and unexpectedly for each patient, even though predictive models can draw an accurate survival curve by averaging the experience of a substantial number of people with heart failure. Heart failure patients often have treatable symptoms, such as dyspnea, fatigue, and generalized pain. In this article, we explain the trajectory of patients with heart failure, illustrate the importance of advance care planning for these patients, discuss the impact of choices to use or forgo new technologies, and suggest ways to improve the care system. Only by reexamining our health care spending priorities can we create a sustainable care system that allows patients to live both long and comfortably, reaching a balance that serves them and their communities well.  相似文献   

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The Nanticoke-Moors of Delaware are an ethnic group of Native American, Afro-American, and Euro-American descent. Their physiognomic and ethnic marginality has subjected them to a limited range of social and economic options under the influence of American racial policies. This article concerns their ethnic formation in the colonial period and the demographic effects (changes in fertility, mortality, and structure) of their 19th- and 20th-century social history. The demographic sample consists of 406 headstones from three community cemeteries. Each cemetery represents a socially and economically distinct unit, including a group that identifies with its traditional Indian heritage, an Afro-American acculturated group, and a migrant community of marginal ethnic affiliation. Variation and change in life expectancy is shown. Relationships between the political and economic processes affecting Nanticoke-Moor social affiliation, and those affecting color caste-class formation among mainstream Afro-Americans, are discussed.  相似文献   

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薛婧妍  刘耕源 《生态学杂志》2018,29(12):4226-4238
城市生态系统内部各组分之间存在着错综复杂的关系,任一组分的变化会对其他组分产生不同程度的影响.快速的城市化进程带来了一系列影响城市可持续发展的问题.若想从根本上消除这些可持续发展隐患,需要采用“耦合”方法.本文明晰了“耦合”的3种应用情景及相应定义表述,同时对城市耦合理论发展脉络进行梳理,分别从物理耦合视角及政策效果耦合视角进行能-水-食物-土地-气候变化(EWFLC)五系统两两分析总结.从物理耦合视角解读发现,目前的耦合研究大多集中在城市尺度,并且主要针对两个系统之间的直接耦合关系,间接耦合关系研究相对缺乏,两系统的关联多会对社会和经济产生积极影响.从政策效果耦合视角来看,目前针对五系统的政策多面向直接解决目标系统问题,政策实施的中间目标大多可量化,且政策效果评估大多含有多个指标.在此基础上,本文提出了可同时结合物理耦合及政策效益耦合的城市EWFLC五系统分析框架,旨在帮助城市开展政策遴选,实现城市可持续发展.  相似文献   

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This paper describes an autonomics development tool which serves as both a powerful and flexible policy-expression language and a policy-based framework that supports the integration and dynamic composition of several autonomic computing techniques including signal processing, automated trend analysis and utility functions. Each of these technologies has specific advantages and applicability to different types of dynamic adaptation. The AGILE platform enables seamless interoperability of the different technologies to each perform various aspects of self-management within a single application. Self-management behaviour is specified using the policy language semantics to bind the various technologies together as required. Since the policy semantics support run-time re-configuration, the self-management architecture is dynamically composable. The policy language and implementation library have integrated support for self-stabilising behaviour, enabling oscillation and other forms of instability to be handled at the policy level with very little effort on the part of the application developer. Example applications are presented to illustrate the integration of different autonomics techniques, and the achievement of dynamic composition.
Richard John AnthonyEmail:
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