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71.
On the Performance of the Subtour Elimination Constraints Approach for the p‐Regions Problem: A Computational Study 下载免费PDF全文
Juan Carlos Duque Mario C. Vélez‐Gallego Laura Catalina Echeverri 《Geographical analysis》2018,50(1):32-52
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
72.
Network Dynamics in Natural Resource Governance: A Case Study of Swiss Landscape Management 下载免费PDF全文
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
73.
Mario Damen 《Journal of Medieval History》2017,43(3):255-284
This article focuses on the social and political features of the knighthood in one of the most densely populated areas of the Low Countries, the administrative district of Brussels, known as the ammanie, in the fifteenth century. A systematic identification of all knights (rather than a selection) enables us to correct Huizinga’s picture and that of other, more recent, historians of the late medieval nobility as a social group in decay. Moreover, this case study contributes to ongoing debates on the position and status of late medieval knighthood. First, the data make it possible to assess the impact of Burgundian policies on the social, political and military relevance of the knighthood of Brabant. Second, special attention is given to their feudal possessions, in particular lordships and fortified residences, in order to establish stratification within the knighthood. Finally, the status and position of bannerets within the Brabantine knighthood is highlighted since they played a crucial role as intermediaries between the duke of Brabant and the urban elites of Brussels. 相似文献
74.
Mario Liong Petula Sik-Ying Ho 《Gender, place and culture : a journal of feminist geography》2019,26(7-9):1081-1093
AbstractIn this short review, we explain the need for a multidimensional analytical framework for exploring how the construction of men and masculinities has shaped Hong Kong’s social and political development, and how politics both enable and constrain men in their lived experiences and practices in various life spheres at the city’s current political juncture. We observe that the majority of the extant research on men and masculinities in Hong Kong is depoliticized, whereas studies on current Hong Kong politics are largely gender-blind. However, the ever-tightening grip of the Chinese Communist Party and the instances of political resistance in response, namely, the Umbrella Movement of 2014 and Fishball Revolution of 2016, suggest that the influence of the wider political situation has penetrated every dimension of life, which has considerable implications for masculine identities and practices. Rather than continuing to conduct the depoliticized masculinity studies and genderless political studies we have seen to date, it is time for a thorough investigation of the dynamic intersection of men’s practices and the political context of Hong Kong. 相似文献
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Mario Poceski 《东方研究杂志》2017,65(1):229-233