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81.
One important extension of the IAD framework has been to the study of local public economies. These are multi‐organizational, multi‐level arrangements defined as the set of governmental jurisdictions, public and nonprofit agencies, and private firms that interact in various patterns to provide and produce public goods and services within a specific locality or region. Commonly, the localities or regions studied from this perspective have been U.S. metropolitan areas, often defined as a central city and its surrounding or adjoining county. Localities can be delineated, however, on various terms, and in the IAD framework, it is the geo‐physical nature of a locality that, in substantial part, drives the analysis. One of the strengths of the approach is its capacity to explain local variations in public organization as a function of the geo‐physical diversity of localities, while at the same time developing empirical generalizations and normative principles that apply across diverse regions. What, for example, might the organization and governance of a complex metropolitan area have in common with the organization and governance of a complex protected area, such as the greater Yellowstone eco‐region or the Adirondack Park? Construing both sorts of regions as local public economies can enhance our overall understanding of public organization at the same time that it permits a more nuanced understanding of diverse localities. Such work contributes to the ongoing IAD project of “understanding institutional diversity.”  相似文献   
82.
Wetlands are common in Coastal Western Hemlock forests yet the hydrologic processes that generate runoff from small swamps are not completely understood. Direct field observations, hydrologic, and electrical conductivity data were collected from a gently sloping forested swamp complex from July to November 2009. Swamps occupied depressions between raised mounds (0.1 to 3 m high) and were connected by an ephemeral creek. Runoff was controlled by antecedent moisture conditions and influenced by basin microtopography. Two hydrologic regimes occurred during the study period and different runoff processes dominated each regime. Runoff was generated by subsurface flow during dry antecedent conditions as swamps remained hydrologically disconnected from each other. Runoff was generated by surface outflow from hydrologically connected swamps during wet antecedent conditions as ponded water spilled out of the depressions. The forested swamp complex produced a faster but limited hydrologic response during dry antecedent conditions compared to a slower but greater hydrologic response during wet antecedent conditions. Stormwater runoff and runoff ratios were up to two orders of magnitude higher in wet conditions than during similarly sized events in dry conditions. These factors should be considered when designing monitoring programs or runoff models in forested swamps with significant microtopography. Field surveys and estimates of hydrologic inputs and outputs may be useful in predicting the potential hydrologic connectivity of isolated forested swamps.  相似文献   
83.
Cable-stayed bridges exhibit unique responses under a strong motion. It is partly due to the complexity in their damping mechanism. Recently, the benchmark problem of a cable-stayed bridge was developed to clarify the effectiveness of various seismic control strategies. Due to the new development of magnetorheological dampers, the application of variable dampers in bridges becomes possible. In this study, the effectiveness of the nonlinear viscous damping force scheme and the two-step friction damping force scheme are investigated. It is found that the nonlinear viscous damping force scheme is effective to control the response of the cable-stayed bridge with less demand for the damping force capacity of a damper. In addition, the two-step friction damping force scheme shows the improvement over conventional friction damping because the energy dissipation of a damper can be increased.  相似文献   
84.
Damage phenomena observed in structures subject to intense seismic events are the result of stiffness and strength degradation. This paper studies the damage assessment of hysteretic degrading structures described by means of the Bouc-Wen model, modified to represent the mechanical degradation induced by severe earthquakes. In order to consider randomness of seismic action, the analysis is performed by adopting a stochastic approach and the Park and Ang damage functional is also evaluated in stochastic way. A parametric analysis is carried out with the aim to analyse the effect of mechanical characteristics and measure parameters of earthquake intensity on seismic response and damage level. Damage spectra are finally obtained and they are used to develop, on the basis of the Performance Based Seismic Design, ductility demand spectra.  相似文献   
85.
Abstract

In view of the compendium of field evidence and supporting analysis work indicating the possible damaging effects of vertical earthquake ground motion, this paper addresses the problem of code-type vertical force calculation. In light of recent engineering seismology studies of the relationship between vertical and horizontal peak ground acceleration, the inadequacy of the 2/3-rule depicted by codes is highlighted. A simple piece-wise linear relationship is proposed and shown to represent existing strong-motion measurements adequately. Bilinear and inelastic spectra are derived and studied. It is demonstrated that net tensile forces and displacements may ensue, thus eroding the shear resistance of RC columns. A simple procedure is outlined whereby modal analysis may be employed to estimate conservatively vertical earthquake forces on buildings. Finally, areas of further exploration and refinement are identified.  相似文献   
86.
For investigating the seismic behaviour of monolithic beam-column joints, a new technique of assessment of joint performance, termed the Shear Deformation Energy Index, is presented in this paper. Previous research efforts in this field were evaluated and the relative merits and drawbacks of each approach were highlighted. Primary variables influencing the seismic behaviour of joints were studied in the experimental phase of the current study. This included pseudo-static testing of nine interior beam-column sub-assemblages with different joint configurations. The parametric investigation of primary variables was complemented by studying the behaviour of specimens of eight different experimental programmes. For easy application of the technique in design practice, the Index is graphically represented versus its main variables in a design chart, referred to as the Performance Chart.  相似文献   
87.
A senior American specialist on China and noted geographer argues that the preoccupation of China geographers' with empirical analyses of that country's dramatic economic, social, and urban transformation over the last two decades—usually explained in terms of the now familiar quadruple forces of globalization, marketization, deregulation, and decentralization—should be broadened to reflect a concern for the problems of disadvantaged groups impacted negatively in dynamic urban and environmental settings. The methodology of reflexive activism is proposed as affording a framework for a more relevant geography focused on the study of China, with the potential to bring about positive and constructive change on behalf of China's disadvantaged population and its natural environment, and (as a possible side benefit) generate local epistemologies enriching the study of geography more broadly. Journal of Economic Literature, Classification Numbers: P30. 68 references.  相似文献   
88.
ABSTRACT

There are growing concerns in South Africa about the threat that acid mine drainage (AMD) poses to local natural water resources in many of the country's mining areas. Since the beginning of the 21st century, the toxic water has been responsible for pollution in parts of the country. Government and operators in the country's water sector have actively been working in recent years at addressing the problem. This article deals with a contemporary history of an AMD crisis in the coalmining town of Carolina, in the Mpumalanga Province of South Africa, and explains how the matter was eventually resolved. The discourse focuses on how people of Carolina responded to the contamination of the municipality's water supply system and eventually chose to follow the path of active protest. The water crisis even made a detour to the high court, with a number of non-governmental organisations (NGOs) actively supporting the cause of local residents. Although by September 2012 the town's water supply was restored, the community remained distrustful of the local authority's ability to secure a consistent supply of good quality water. The authorities took some measures to restore trust. People had been traumatised and sound relations had to be restored in the aftermath of the crisis. The Carolina crisis of 2012 is contemplated from the perspective of the current threat that AMD poses to South Africa's finite water resources and the danger of mining in sensitive areas.  相似文献   
89.
In this paper, we look at what it means to ‘eat Hawai'i’ and examine how Hawai'i Regional Cuisine (HRC) imagines, produces, and consumes place through particular constructions of local foods. The term ‘local’ attaches to foods as a marker of numerous positive attributes such as seasonal, sustainable, and community-based. Drawing upon ongoing ethnographic research on Hawai'i Island, we examine spatial and discursive constructions of local and how this particular cuisine places itself in local food networks while simultaneously using place to localize itself within the Island's food networks. Using a case study approach to carefully contextualize localness, we show how Merriman's Restaurant and HRC complicate notions of alternative and local food systems in its discursive and material production and reproduction of Local food and locally grown food.  相似文献   
90.
在清代的佛山镇,义仓几乎承担了所有的地方善举,成为地域社会的"善举联合体"。佛山义仓的运作机制,不是对宗族公产房支轮值原则的简单移植,而是将"九社""八图""二十七铺"的里社组织融入到义仓的管理中,且在义仓管理中,力求革除豪族对义仓公产的强占,从而使义仓成为佛山地方善举的母体。在社会联结的意义上,围绕北帝信仰的祖庙,在空间和象征上成为佛山镇公共管理的黏合剂。  相似文献   
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