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This article examines the impact of the Cold War on the Italian political system. It compares the relations of the two main Italian parties - the DC and the PCI - with their external interlocutors and allies - the USA and the USSR - during the first decade of the Cold War. By doing so, the article rejects traditional interpretations of how post-Second World War international constraints limited Italy's sovereignty. It argues instead that the main Italian pro-western party, the Christian Democrats, deliberately opted for a policy of containment of American pressures. Such a policy was functional to the twin objectives of consolidating DC hegemony, and safeguarding Italy's new republican constitution.  相似文献   
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Theories of policymaking often focus on subsystems within a larger, overarching governance system. However, subsystem identification is complicated by the complexity of governance systems, characterized by multiple, interrelated issues, multi-level interactions, and a diverse set of organizations. This study suggests an empirical, bottom-up methodology to identify subsystems. Subsystems are identified based on bundles of similar observed organizational activity. The study further suggests a set of three elementary criteria to classify individual subsystems. In order to prove the value of the methodology, subsystems are identified through cluster analysis, and subsequently classified in a study of Swiss water governance. Results suggest that Swiss water governance can be understood as a network of overlapping subsystems connected by boundary penetrating organizations, with high-conflict and quiet politics subgroups. The study shows that a principled analysis of subsystems as the interconnected, constituent parts of complex governance systems offers insights into important contextual factors shaping outcomes. Such insights are prerequisite knowledge in order to understand and navigate complex systems for researchers and practitioners alike.  相似文献   
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过去五十多年里,在对意大利的石雕和大型青铜雕塑进行保护时,各种跨学科的深度评估方法得到了建立。在此框架内,射线照相检测技术取得了进步。射线照相术作为一种无损的研究手段,可以从宏观层面对艺术作品进行考察,在文物评估中一直发挥着核心作用。在检测阶段,射线照相术既可以被用来重构古代艺术工艺和流程,也可以被用来评估文物的机械和结构信息。本文介绍了射线照相术的研究历史及其不同方法,比如中能X射线的使用、高能X射线的应用(线性加速器)、伽马放射性同位素源的使用(伽马射线照相术)。本文描述了射线照相术在石质和青铜雕塑上的重要应用案例,其中对马可·奥勒留骑马像的研究就是一个典型。本文还描述了“高能X射线”的首次应用,该技术被用来检测奥维多大教堂的圣母子、两组天使和一个青铜天篷雕塑。文章的结论部分定义了正确解释数据结果的必要标准,特别是在通过射线照相检测技术探究青铜雕塑检测信息和铸造工艺的相关性时,应该考虑到铸造缺陷和不连续性。  相似文献   
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The p‐regions is a mixed integer programming (MIP) model for the exhaustive clustering of a set of n geographic areas into p spatially contiguous regions while minimizing measures of intraregional heterogeneity. This is an NP‐hard problem that requires a constant research of strategies to increase the size of instances that can be solved using exact optimization techniques. In this article, we explore the benefits of an iterative process that begins by solving the relaxed version of the p‐regions that removes the constraints that guarantee the spatial contiguity of the regions. Then, additional constraints are incorporated iteratively to solve spatial discontinuities in the regions. In particular we explore the relationship between the level of spatial autocorrelation of the aggregation variable and the benefits obtained from this iterative process. The results show that high levels of spatial autocorrelation reduce computational times because the spatial patterns tend to create spatially contiguous regions. However, we found that the greatest benefits are obtained in two situations: (1) when ; and (2) when the parameter p is close to the number of clusters in the spatial pattern of the aggregation variable.  相似文献   
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The St. John Hospital is part of a larger complex of buildings known as the Hospitallers Quarter, located south of the Holy Sepulchre in Jerusalem. At present, the hospital looks like an irregular volume both in height and in plan; it is covered by ten groin vaults resting on very stocky pillars. Each vault is formed by intersecting double curvature surfaces. In order to verify the effectiveness of continuous carbon fiber reinforced polymer sheets reinforcement, bonded at the extrados of vaults, laboratory tests were carried out on a 1:5 scale model, built with materials and construction techniques similar to those of the real building. Experimental tests were performed on the unstrengthened and strengthened vault. The experimental results shown that the strengthening system is able to increase the collapse load of the vault, without substantial variation of the initial stiffness.  相似文献   
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Structural characteristics of social networks have been recognized as important factors of effective natural resource governance. However, network analyses of natural resource governance most often remain static, even though governance is an inherently dynamic process. In this article, we investigate the evolution of a social network of organizational actors involved in the governance of natural resources in a regional nature park project in Switzerland. We ask how the maturation of a governance network affects bonding social capital and centralization in the network. Applying separable temporal exponential random graph modeling (STERGM), we test two hypotheses based on the risk hypothesis by Berardo and Scholz (2010) in a longitudinal setting. Results show that network dynamics clearly follow the expected trend toward generating bonding social capital but do not imply a shift toward less hierarchical and more decentralized structures over time. We investigate how these structural processes may contribute to network effectiveness over time.  相似文献   
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