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71.
Andreas Angourakis José Ignacio Santos José Manuel Galán Andrea L. Balbo 《Environmental Archaeology》2015,20(4):349-363
AbstractA 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
72.
Biodiversity and Environmental Change: Monitoring,Challenges and Direction edited by D. LINDENMAYER,E. BURNS,N. THURGATE and A. LOWE (eds), CSIRO Publishing,Melbourne, Australia, 2014, xiv + 624 pp,ISBN: 9780643108561 (hardback), AU$120.00
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CATE MACINNIS‐NG 《Geographical Research》2015,53(2):226-227
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Zoltán Boldizsár Simon 《European Review of History》2015,22(5):819-834
An essential element usually passes unnoticed in recent discussion about how history as an academic discipline is supposed to be relevant for the shaping of our public life. It is the concept of history itself (history as both the course of events and historical writing) that underlies the whole discussion, which also configures the two currently most influential and fashionable efforts to reinstate the public relevance of history: The History Manifesto, co-authored by Jo Guldi and David Armitage, and Hayden White's The Practical Past. In advising to turn to the past in order to shape the present and the future, both books rely on the familiar developmental view that characterised nineteenth-century thinking in general, and on which the discipline of history became institutionalised in particular. The author's main contention in this essay is that turning to this notion of history is not the solution for the problem of the supposed public irrelevance of professional historical studies, but the problem itself. The developmental view, based on a presumption of a deeper continuity provided by the subject of the historical process that retains its self-identity amid all changes, certainly suited the discipline of history when it was engaged in the project of nation-building. However, it hardly fits our present concerns. These concerns, like the Anthropocene, take the shape of unprecedented change, and what they challenge is precisely the deeper continuity of the developmental view. The discipline of history can regain public relevance only insofar as it proves to be able to exhibit a thinking of its own specificity which can nevertheless explain such unprecedented changes. What such historical thinking could provide is what the developmental view can no longer: the possibility to act upon a story that we can believe. 相似文献
75.
Balázs István Tóth 《European Planning Studies》2015,23(7):1327-1344
Territorial capital has gained considerable attention in the past few years. The aim with this work is to throw light on some underlying aspects of territorial capital research. The study focuses on the theoretical and empirical issues of territorial capital and highlights some critical remarks related to the topic. On the one hand, the focus of the study is on the comparison of concepts and approaches in connection with territorial capital; then an in-depth look is taken at “capital frameworks” related to the research field. On the other hand, a comprehensive overview is presented of empirical investigations by comparing the applied methods, dimensions and variables of territorial capital. An argument is also made for a critical assessment concerning the topic with regard to the sense and function of territorial capital in regional economics and local economic development and highlights some further dilemmas concerning the “properties of capital” and “territorial capital paradigm”. Finally, some suggestions are provided for the future of territorial capital analysis. The main result of the study is an own belief in the concept of territorial capital. 相似文献
76.
Latent trajectory models for space‐time analysis: An application in deciphering spatial panel data
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Li An Ming‐Hsiang Tsou Brian H. Spitzberg Dipak K. Gupta J. Mark Gawron 《Geographical analysis》2016,48(3):314-336
This article introduces latent trajectory models (LTMs), an approach often employed in social sciences to handle longitudinal data, to the arena of GIScience, particularly space‐time analysis. Using the space‐time data collected at county level for the whole United States through webpage search on the keyword “climate change,” we show that LTMs, when combined with eigenvector filtering of spatial dependence in data, are very useful in unveiling temporal trends hidden in such data: the webpage‐data derived popularity measure for climate change has been increasing from December 2011 to March 2013, but the increase rate has been slowing down. In addition, LTMs help reveal potential mechanisms behind observed space‐time trajectories through linking the webpage‐data derived popularity measure about climate change to a set of socio‐demographic covariates. Our analysis shows that controlling for population density, greater drought exposure, higher percent of people who are 16 years old or above, and higher household income are positively predictive of the trajectory slopes. Higher percentages of Republicans and number of hot days in summer are negatively related to the trajectory slopes. Implications of these results are examined, concluding with consideration of the potential utility of LTMs in space‐time analysis and more generally in GIScience. 相似文献
77.
Characterization of a Historical Cannonball from the Fortress of San Juan De Ulúa Exposed to a Marine Environment
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M. Hernandez M. Hernandez‐Escampa C. Abreu J. Uruchurtu M. Bethencourt A. Covelo 《Archaeometry》2016,58(4):610-623
Metallurgical analyses and chemical characterizations were carried out on historical cannonballs from the Fortress of San Juan de Ulúa, Veracruz, México. Cannonballs dating from the 18th and 19th centuries share metallurgical characteristics similar to those of material coming from a shipment of ammunition found in the wreck of a sunken French ship from the battle of Trafalgar. The analyses show that the base material is grey cast iron with a carbon equivalent of 4.94 and a ferritic–perlitic matrix, in which the high phosphorus content has led to the formation of iron phosphide compounds in conjunction with a homogeneous distribution of carbon graphite flakes of Type C. In addition, corrosion products from samples revealed the presence of various crystalline iron compounds (X‐ray diffraction), mostly highly chlorinated iron compounds identified as akaganeite. X‐ray fluorescence identified various characteristics of the corrosion products as a function of the sampling depth. FT–IR spectroscopy revealed that the main difference between the corrosion products (internal and external) is determined by the number of organic species. Differential scanning calorimetry corroborated that these corrosion products are thermally stable compounds at elevated temperatures. 相似文献
78.
A Box Containing Carpenter's Accessories from The Akko 1 Shipwreck,Israel: Archaeometallurgical Analysis of Surviving Ironwork
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The Akko 1 shipwreck was an Egyptian armed vessel, built at the beginning of the 19th century. A wooden saw handle and a box containing iron nails and two split pins were discovered towards the stern. Given their function, location and context, these were part of the ship's carpenter's tools and accessories. A methodology was developed for conducting systematic metallurgical analysis in order to understand the manufacturing process of the surviving ironwork items, as well as to enlarge our knowledge regarding ironworking technologies during the early 19th century. Such methodology may assist in the future understanding of the technological evolution of similar wrought‐iron objects. The results demonstrated that the artefacts have a wrought‐iron heterogeneous microstructure and were manufactured by hot‐working prior to surface hardening by pack carburization. 相似文献
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