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1.
In this paper, I present an intensive case study of the development of the National Flood Insurance Program to advance two key arguments. First, the conventional model of adoption of general interest reform neglects an important aspect of political context: whether the relevant policy domain is one with or without “publics.” I argue that in domains without publics the politics of reform will differ substantially from the accepted model. Second, I argue that the type of learning necessary to address a given policy failure matters in reform politics. Instrumental learning is necessary but may not be sufficient for successful general interest reforms. When the social construction of a policy failure is such that many people misconceive of the fundamental purpose of a policy, social learning must take place before instrumental learning can be effective.  相似文献   
2.
Nicholas Beuret 《对极》2017,49(5):1164-1185
The environmental movement in the global North is in a state of impasse. It appears that despite the renewed international focus on climate change, and the actions of innumerable social movements, a “solution” to the problem appears as one, without a viable solution. It is the contention of this paper that climate change has no clearly viable solution as it is a seemingly impossible problem. This paper investigates how the problem of climate change is constructed as a global object of political action and how it functions to render politics into a matter of calculative action, one that seeks—but fails—to take hold of a slippery carbon infrastructure. It concludes by suggesting one possible solution to this dilemma is to turn away from the global scalar logic of climate change and towards a situated focus on questions of infrastructure, or what Dimitris Papadopoulos calls “thick justice”.  相似文献   
3.
Studies of failure typically assess public policies through the lenses of effectiveness, efficiency, and performance. Here I wish to propose a further dimension to the evaluation and assessment of policy failure—legitimacy. The substantive elements of public policies and the procedural steps taken by authoritative decision makers during the policy cycle affect the perception of policy legitimacy held by both stakeholders and the public. In substantive terms, policy content should align with the dominant attitudes of the affected policy community and, ideally, the broader public. Procedurally, factors such as policy incubation, the emotive appeals deployed to gain support for an initiative, and the processes of stakeholder engagement shape the legitimacy of public policies and the governments who promote them. This argument is based on a comparison of education reform in two Canadian provinces during the 1990s. Governments in Alberta and Ontario pursued common agendas of education reform, but while Alberta achieved success, the Ontario government experienced a series of setbacks and lost the support of education stakeholders and the public. The root of Ontario's failures lies in the realm of legitimacy. These findings highlight the fact that the strategies used for enacting policy change may fail to bring about the necessary consensus among societal actors to sustain a new policy direction and calls attention to our need to better understand how governments can achieve meaningful public participation while still achieving legislative success in an efficient fashion.  相似文献   
4.
V. Vilarrasa 《Geofluids》2016,16(5):941-953
Fluid injection in deep geological formations usually induces microseismicity. In particular, industrial‐scale injection of CO2 may induce a large number of microseismic events. Since CO2 is likely to reach the storage formation at a lower temperature than that corresponding to the geothermal gradient, both overpressure and cooling decrease the effective stresses and may induce microseismicity. Here, we investigate the effect of the stress regime on the effective stress evolution and fracture stability when injecting cold CO2 through a horizontal well in a deep saline formation. Simulation results show that when only overpressure occurs, the vertical total stress remains practically constant, but the horizontal total stresses increase proportionally to overpressure. These hydro‐mechanical stress changes result in a slight improvement in fracture stability in normal faulting stress regimes because the decrease in deviatoric stress offsets the decrease in effective stresses produced by overpressure. However, fracture stability significantly decreases in reverse faulting stress regimes because the size of the Mohr circle increases in addition to being displaced towards failure conditions. Fracture stability also decreases in strike slip stress regimes because the Mohr circle maintains its size and is shifted towards the yield surface a magnitude equal to overpressure minus the increase in the horizontal total stresses. Additionally, cooling induces a thermal stress reduction in all directions, but larger in the out‐of‐plane direction. This stress anisotropy causes, apart from a displacement of the Mohr circle towards the yield surface, an increase in the size of the Mohr circle. These two effects decrease fracture stability, resulting in the strike slip being the least stable stress regime when cooling occurs, followed by the reverse faulting and the normal faulting stress regimes. Thus, characterizing the stress state is crucial to determine the maximum sustainable injection pressure and maximum temperature drop to safely inject CO2.  相似文献   
5.
Many analysts are concerned about territories subject to state failure becoming safe havens for terrorists. In this article, I apply this logic to maritime piracy syndicates and their ship hijacking operations, and argue that a focus on the geographies of state failure can help us explain why pirates' behavior varies between failed and weak states. Analysis of a dataset of hijacking incidents suggests that state failure is associated with less sophisticated attacks, while state weakness encourages more sophisticated attacks. Through case studies of the process by which pirates carry out their attacks in East Africa and Southeast Asia, I argue that it is the differences in political and economic landscapes that influence how pirates embed their operations across territory, and thus how they carry out their operations. Notably, because they do not have to worry about enforcement, pirates in failed states can engage in time-intensive kidnappings for ransom, while only weak states provide the markets and transportation infrastructure necessary for operations where ships and cargo are seized and sold for profit. These findings suggest that weak states might actually be more problematic for international security in some respects than failed states.  相似文献   
6.
Why do policies fail? There are many answers to this question, and many ways of answering it. In this paper, we use the tools of policy framing and systems thinking to investigate two recent Australian examples of public policy failure, each involving a different policy milieu and time-span. We show that, in both these cases, unintended consequences arose because governments lost control of the implementation process while remaining politically accountable for the outcomes. We develop the concept of transmitted risk to show how this occurred. We argue that governments expose themselves to this kind of risk when they make policy decisions involving a combination of excessive incentives and poorly controlled third parties.  相似文献   
7.
Obituaries     
Abstract

A rich variety of processes have modified the glacial landscape of the Scottish Highlands since the last glaciers disappeared 11,500 years ago. Many of these processes can be described as paraglacial (glacially-conditioned): retreat of glacier ice has resulted in exposure of metastable sediment sources (rock slopes, drift-mantled slopes and valley-floor glacigenic deposits) that have been reworked over a range of timescales. Much of the reworked sediment has been deposited in paraglacial sediment stores (talus accumulations, debris cones, alluvial fans, valley fills, river terraces and deltas). The trajectory of paraglacial sediment transfer can be approximated by an exhaustion model. A corollary of this model is that all sediment stores eventually undergo a change from net accumulation to net erosion, reflecting the non-renewable nature of sediment sources. This concept helps to explain why most talus accumulations, debris cones and alluvial fans in the Highlands are now relict, and why many floodplains appear to have experienced an initial period of aggradation followed by later river incision and terrace development. Since deglaciation, rock slopes have experienced paraglacial stress release due to differential deglacial unloading. Many rock slopes have remained stable or experienced gradual adjustment through intermittent rockfall. At over 600 sites, however, large-scale rock-slope failure has occurred, either in the form of catastrophic failure with complete or arrested debris runout, or as major slope deformations. Modification of drift-mantled slopes has been dominated by rainstorm-generated debris flows activity, which have stripped sediment from slopes and redeposited it in debris cones. Radiocarbon dating of buried organic horizons shows that debris flows have occurred intermittently throughout the Holocene. Snow avalanches have played only a localized role in paraglacial sediment transfer. The Holocene alluvial history of the Highlands is poorly understood. Some alluvial fans formed during a few exceptional flood events, and there is evidence that postglacial floodplain aggradation peaked in the late Holocene and was succeeded by floodplain incision and terrace development, possibly reflecting upstream reduction in paraglacial sediment supply. Other processes have operated independently of glacial conditioning. The effects of wind action are dominant in the coastal zone, forming dunefields through aeolian reworking of beach sand, and on plateaux in the form of deflation surfaces and sand sheets. Extensive erosion of plateau-top sands and aeolisols occurred in the period AD 1550–1700, a period of exceptional storminess. Small-scale periglacial processes have also been active on high ground throughout the Holocene, including granular weathering of exposed rock surfaces, the development of small-scale frost-sorted patterned ground on unvegetated terrain, and slow downslope movement of solifluction sheets, solifluction lobes and ploughing boulders.  相似文献   
8.
Little is known of hard-rock coastal landsliding in Scotland. We identify 128 individual coastal landslides or landslide complexes >50 m wide along the coasts of Shetland. Most are apparently translational slides characterized by headscarps, displaced blocks and/or debris runout, but 13 deep-seated failures with tension cracks up to 200 m inland from cliff crests were also identified. Thirty-one sites exhibit evidence of at least localized recent activity. Landslide distribution is primarily determined by the distribution of coastal cliffs >30 m high, and they are preferentially developed on metasedimentary rocks. Analysis of 16 landslides on Fetlar (NE Shetland) indicates that most are translational dip-slip failures; 3 represent deep-seated failures and several exhibit active frontal erosion attributable to basal sapping by storm waves. As these landslides terminate in shallow water, failure was probably initiated when rising sea level resulted in footslope erosion and upslope propagation of instability, causing downslope displacement of landslide blocks on upper slopes. 10Be exposure dating of two headscarps yielded ages of 4.8?±?0.2 ka and 4.4?±?0.2 ka, consistent with the onset of footslope erosion as sea level rose. Our results suggest that landslides have played a hitherto undocumented but important role in retreat of cliffed coastlines in Scotland.  相似文献   
9.
环氧树脂类粘结材料目前已成为文物保护工作中常用的粘结材料。但是,在一些应用案例中经常发现环氧树脂类粘结材料有变色、脆化、剥落等老化现象。为了了解环氧类粘结材料的老化规律,摸清材料成分、配方和环境因素的影响,以通用双酚A型环氧树脂为主剂与各种典型固化剂、稀释剂、偶联剂等配制成黏结材料,模拟自然界极端环境条件,通过反复的破坏循环实验,探讨典型环氧类粘结材料的老化过程和机理。  相似文献   
10.
An experimental program for identifying the causes of failures in structural walls under earthquake loading and investigating potential rehabilitation schemes was undertaken. Large-scale models of the plastic hinge region of the walls were tested. An innovative test setup that provides the possibility of controlling the ratio of the shear force to both bending moment and axial load was constructed. A control wall was tested and failed prematurely in shear reproducing the failure observed in the field. Two different rehabilitation schemes to improve the behaviour of the wall using biaxial fibre reinforced polymer (FRP) sheets were designed to prevent the shear failure. To improve the ductility, the end column elements of the walls were confined using anchored FRP. The two schemes were tested and proved to be effective in increasing shear strength, ductility, and energy dissipation capacity of the walls.  相似文献   
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