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Abstract

A consistent access to food is paramount for humans at individual and group level. Besides providing the basic nutritional needs, access to food defines social structures and has stimulated innovation in food procurement, processing and storage. We focus on the social aspects of food storage, namely the role of cooperation for the emergence and maintenance of common stocks. Cooperative food stocks are examined here as a type of common-pool resource, where appropriators must cooperate to avoid shortage (i.e. the tragedy of commons). ‘Food for all’ is an agent-based model in which agents face the social dilemma of whether or not to store in a cooperative stock, adapting their strategies through a simple reinforcement learning mechanism. The model provides insights on the evolution of cooperation in terms of storage efficiency and considering the presence of social norms that regulate reciprocity. For cooperative food storage to emerge and be maintained, a significant dependency on the stored food and some degree of external pressure are needed. In fact, cooperative food storage emerges as the best performing strategy when facing environmental stress. Likewise, an intermediate control over reciprocity favours cooperation for food storage, suggesting that concepts of closed reciprocity are precursors to cooperative stocks, while excess control over reciprocity is detrimental for such institution.  相似文献   
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We present the results of six years of archaeological work carried out in Heping Dao, Keelung, northern Taiwan. The site has revealed a rich archaeological record spanning a sequence that comprehends most of the history of Taiwan, including the most salient historical landmarks in it. The study of this long-term sequence of habitation in Heping Dao throughout prehistory to current times, allows us to attempt a historical archaeology of the longue duree of the place that in turn enables the establishment of comparisons between periods and raising of specific questions, among them: the general understanding of cultural transformation along the Neolithic and the Iron Age, and in turn the transition Iron Age/Aboriginal historic times in Taiwan, which in our view has to be observed as a history of continuity rather than of interruptions; the recognition of the Chinese presence in Taiwan in the pre-European period; the implantation of the European colony and its effects on the local populations; the differing material remains and impacts caused by the presence of pre-European Chinese and the Qing occupation; and the potential for a comparison between the European and the Japanese colonial projects as seen in the material record.  相似文献   
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In the scope of European Cooperation in Science and Technology–Wood Science for Conservation of Cultural Heritage (COST IE0601–WoodCultHer) (available at http://www.woodculther.org) it was agreed to produce Guidelines for the Assessment of Historic Timber Structures, covering the principles and possible approaches for the safety assessment of old timber structures of historical relevance that could be used as the basis for possible European Standards, as discussed with CEN/TC346 (Conservation of Cultural Heritage).

This approach was targeted at all those concerned with the conservation of heritage buildings. These guidelines should also help decision-making regarding the need for immediate safety measures. The aim is to guarantee that inspection and assessment measures provide the necessary data for historical analysis, structural safety assessment, and planning of intervention works, while having minimal impact on the building fabric (the original materials, structural systems, and techniques).This article provides information on the criteria to be used in the assessment of load-bearing timber structures in heritage buildings. It covers the preliminary assessment (desk survey, preliminary visual survey, measured survey, structural analysis, and preliminary report), as well as the detailed survey of timbers (with a special emphasis on visual strength grading on site) and carpentry joints. The subsequent diagnostic report and the detailed design of repairs are outside its scope.  相似文献   

45.
  总被引:1,自引:0,他引:1  
Abstract. This paper models externalities of production across regional economies. Under the assumption that knowledge diffuses without political or administrative barriers, we derive externalities that affect the steady state and the process of growth of each economy. The empirical counterpart of the reduced form equation summarizing the process of growth allows us to test for the presence of regional spillovers and to measure their magnitude. Our results for a sample of European regions show that spillovers are far from negligible, are robust to the consideration of variables within each region, and may cause nondecreasing returns at the spatial aggregate level. The paper also relates previous empirical evidence on spatial dependence in growth studies to the externalities modeled here.  相似文献   
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Fostering border relations among the people in border regions seems a precondition for the future envisagement and success of cross-border regions and European Integration. Related studies to border relations observe the weakness of these informal border contacts and relations. However, weak ties represent an opportunity for interaction, and little has been said about how they might play in the construction and performance of institutional cross-border cooperation (CBC). In this work, we examine the nature of personal border networks of professionals working in CBC and how they are interconnected with the institutional CBC. This paper is based on a mainly qualitative research of two different border regions: Andalusia, Algarve and Alentejo (AAA) and South Finland and Estonia (SFE). Nevertheless, the methodology is multi-method, using semi-structured interviews, with specific questions for applying a social network analysis. Conclusions point out different patterns of border relations in both border regions. In AAA, most of the cross-border relations are weaker and related to their professional involvement in institutional CBC. In SFE, border relations rely both on working and personal reasons. All of these cross-border relations imply a significant value as opportunities for social capital construction across the borders and, hence, for greater interaction and cross-border integration.  相似文献   
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