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Research on coalitions in the policy process has found evidence of both short-term and long-term coalitions. Two possible methodological reasons for the varied results are that (1) there has been little systematic longitudinal research on the topic, and (2) most scholars have not distinguished situations where fundamental versus secondary interests are at stake. This article addresses both points by first applying the Advocacy Coalition Framework (ACF), which distinguishes fundamental from secondary beliefs/interests, and then performing a quantitative analysis of the content of organizations' testimonies regarding automotive pollution control over 26 years. Consistent with the ACF, we find that coalitions of interest groups, legislators, local governments, and agencies are relatively stable over time, despite two potentially disruptive events—the 1973–74 Oil Embargo and the 1980 Elections. On the other hand, there is little support for the ACF's hypothesis that broader beliefs will be more stable than narrower secondary beliefs. Our systematic methodology also enables us to separate the general pattern of stability from interesting exceptions of instability. 相似文献
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We present the combination of an analysis of resource demand by the early post-contact (1721) Cherokee population with spatially explicit estimates of production for five key resources: architectural land, agricultural land, firewood, hard mast, and white-tailed deer (Odocoileus virginianus). We combine a recent synthesis of village location and population, a map of recognized Cherokee territory, digital terrain data, estimates of per capita demand, and productive capacity for each resource. Average, high, and low demands were estimated for each resource and assigned based on a weighted function of terrain and distance from each village. We conclude that Cherokee demands for architectural and agricultural land, hard mast, and fuelwood were easily met within a short proximity to each town under all combinations of production and demand. These resources were likely not limiting, and were satisfied for the entire Cherokee population by less than 1% of the entire recognized Cherokee territory in 1721. These resources likely exceeded demand even when sources were restricted to the convex hull of the Cherokee territory, or to near stream, flat regions. Deer resources were likely harvested over a much larger area and to a much greater extent. Our best estimate of deer resource demand was 32% of annual sustainable production in the Cherokee territory, with from 16 to 48% of estimated sustainable production harvested for low and high demand estimates, respectively. Our estimates vary in response to uncertainties in deer production, harvest proportion, deer density, and sustainable harvest rates. Deer demand was substantially higher under all combinations of conditions than that available within the convex hull of Cherokee villages, indicating significant travel was needed to furnish deer requirements. Spatially explicit models that consider terrain- and distance-related tradeoffs suggest that Cherokee demand for deer drove harvest over areas consisting of over half the recognized Cherokee territory. 相似文献
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Equations of state for basin geofluids: algorithm review and intercomparison for brines 总被引:1,自引:0,他引:1
Physical properties of formation waters in sedimentary basins can vary by more than 25% for density and by one order of magnitude for viscosity. Density differences may enhance or retard flow driven by other mechanisms and can initiate buoyancy‐driven flow. For a given driving force, the flow rate and injectivity depend on viscosity and permeability. Thus, variations in the density and viscosity of formation waters may have or had a significant effect on the flow pattern in a sedimentary basin, with consequences for various basin processes. Therefore, it is critical to correctly estimate water properties at formation conditions for proper representation and interpretation of present flow systems, and for numerical simulations of basin evolution, hydrocarbon migration, ore genesis, and fate of injected fluids in sedimentary basins. Algorithms published over the years to calculate water density and viscosity as a function of temperature, pressure and salinity are based on empirical fitting of laboratory‐measured properties of predominantly NaCl solutions, but also field brines. A review and comparison of various algorithms are presented here, both in terms of applicability range and estimates of density and viscosity. The paucity of measured formation‐water properties at in situ conditions hinders a definitive conclusion regarding the validity of any of these algorithms. However, the comparison indicates the versatility of the various algorithms in various ranges of conditions found in sedimentary basins. The applicability of these algorithms to the density of formation waters in the Alberta Basin is also examined using a high‐quality database of 4854 water analyses. Consideration is also given to the percentage of cations that are heavier than Na in the waters. 相似文献
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This article reviews the state of the two security and defence institutions available to west Europeans: NATO and the EU's common European Security and Defence Policy (ESDP). In each case, the authors assess the political maturity and stability of the institution, and then ask what it can contribute in terms of coordinated military capability to west European's strategic readiness. NATO's Prague summit in November 2002 will address the thorny issue of the next tranche of post–Cold War enlargement. But beyond the predictable debate about which candidates to admit, and what should be offered to those unsuccessful in their bid, there will be a far more urgent and important agenda to be discussed at Prague—the military capabilities of the European allies. Given that ESDP is still far from achieving its capability goals, the authors argue that the time is right for European allies to begin thinking in terms of generating a composite, joint strike force which could be configured to be interoperable with US forces and which could salvage something useful from the disheartening lack of progress in developing a European military capability. 相似文献