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21.
Timothy M. LaPira 《政策研究杂志》2014,42(2):226-251
Does the emergence of a new boundary‐spanning policy regime shift the focus of well‐established organized interests, or does it mobilize new ones? In this article, I show that interest groups with a presence in Washington before 9/11 rapidly—but temporarily—shift their attention to the homeland security issues. Established groups' entrenchment in antecedent subsystems appears to buffer against widespread policy disruption and interest upheaval. However, a new set of previously latent groups opportunistically mobilizes after the regime is institutionalized. Newly mobilized groups replace those that retreat back to the regime's antecedent subsystems. Though the policy regime fails to resolve the jurisdictional turf conflicts that triggered its creation, the institutionalization of homeland security generates its own original, distinct government demand for lobbying. Interests that previously had no business in Washington before 9/11 took advantage of the new opportunities the regime offered without supplanting interests established long before the Department of Homeland Security and its congressional committees existed. 相似文献
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Prehistory vs. Archaeology: Terms of Engagement 总被引:1,自引:1,他引:0
Timothy Taylor 《Journal of World Prehistory》2008,21(1):1-18
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MEASURING THE IMPACT OF AIR POLLUTION ON PROPERTY VALUES 总被引:1,自引:0,他引:1
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Richard L. Francis Timothy J. Lowe Gerard Rushton M. Brenda Rayco 《Geographical analysis》1999,31(1):67-87
When solving a location problem using aggregated units to represent demand, it is well known that the process of aggregation introduces error. Research has focussed on individual components of error, with little work on identifying and controlling total error. We provide a focussed review of some of this literature and suggest a strategy for controlling total error. Consideration of alternative criteria for evaluating aggregation schemes shows that the method selected should be compatible with the objectives of the analyses in which it is used. Experiments are described that show that two different measures of error are related in a nonlinear way to the number of aggregate demand points (q), for any value of the number of facilities (p). We focus on the parameter q/p and show that it is critical for determining the expected severity of the error. Many practical implementations of location algorithms operate within the range of q/p where the rate of change of error with respect to q/p is highest. 相似文献
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What really goes on in Silicon Valley? Spatial clustering and dispersal in modular production networks 总被引:3,自引:0,他引:3
Is the geographic trajectory of capitalism toward spatial clusteringor dispersal? Recent theoretical work in the stream of relationaleconomic geography includes several dynamic elements that increasethe importance of spatial clustering over time. This paper developsthe concept of modular production networks toshow that spatial clustering and dispersal can be compatible,mutually reinforcing trends. Modular production networks encompassnodes of tacit activity linked through the exchange of codifiedinformation to create global-scale production systems. In placeslike Silicon Valley, industry participants rely on the benefitsof proximity to help build and manage global-scale productionnetworks. 相似文献
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There is a long history of human interaction with plants of the Aroideae subfamily (Araceae). Despite these plants' chemical defenses against animal and vegetal predation, humans have targeted their starchy corms, tubers and rhizomes for dietary purposes. In the Eastern Woodlands of North America, early Europeans described the Native population as utilizing the highly acridic Peltandra virginica (arrow arum) for subsistence needs. In order to render this resource edible, however, the acridic principle first needs to be eliminated. Our study investigates the affect these processing activities have on the integrity of arrow arum starch grains. Findings from this study demonstrate that environmental variables specific to individual processing procedures may be more influential on starch grain survival than simply the temperatures reached during cooking. 相似文献