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ABSTRACT. Recursive algorithms for the elimination of redundant paths in spatial lag operators are introduced. It is shown that these algorithms have superior computational properties in comparison with the cumbersome procedure proposed by Ross and Harary (1952). A rigorous definition of spatial lag operators is given, while a number of mathematical results and properties are derived. Theoretical and empirical results regarding the performance of the proposed algorithms are presented. 相似文献
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Dieter Franz Kogler Gaston Heimeriks Loet Leydesdorff 《European Planning Studies》2018,26(11):2256-2278
ABSTRACTCities can be considered as engines of the knowledge-based economy, because they are the primary sites of knowledge production activities that subsequently shape the rate and direction of technological change and economic growth. Patents provide rich information to analyse the knowledge specialization of specific places, such as technological details and information on inventors and entities involved. The technology codes attributed at the level of individual patent documents can be used to indicate the diversity and scope of the knowledge claims underlying a specific invention. In this study we introduce tools for portfolio analysis in terms of patents that provide insights into the technological specialization of cities. The mapping and analysis of patent portfolios of cities exploits data derived from the Unites States Patent and Trademark Office (USPTO) and dedicated tools (at https://leydesdorff.net/software/patents/). The results allow policy makers and other stakeholders to identify promising areas of further knowledge development, including smart specialization strategies. 相似文献
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Hans Harmsen Jørgen Hollesen Christian Koch Madsen Bo Albrechtsen Mikkel Myrup Henning Matthiesen 《Conservation and Management of Archaeological Sites》2018,20(4):175-198
ABSTRACTEvaluating the rate of deterioration at archaeological sites in the Arctic presents several challenges. In West Greenland, for example, increasing soil temperatures, perennial thaws, coastal erosion, storm surges, changing microbial communities, and pioneer plant species are observed as increasingly detrimental to the survival of organic archaeological deposits found scattered along the country’s littoral zones and extensive inner fjord systems. This article discusses recent efforts by the REMAINS of Greenland project for developing a standardised protocol that defines the archaeological state of preservation, the preservation conditions, and asset value of organic deposits. Special emphasis is given to the degradation of materials such as bone and wood that are historically observed to be well-preserved in Greenland but now currently at risk. The protocol provides a baseline for monitoring future changes and will assist archaeologists in Greenland with a procedure for documenting and predicting areas of increasing vulnerability due to a warming climate. 相似文献
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Eva Svensson Hilde Rigmor Amundsen Ingunn Holm Hans Hulling Annie Johansson Jan Löfgren 《International Journal of Heritage Studies》2018,24(1):17-34
There is a rich, but unacknowledged, heritage of rural subalterns, crofters, in Scandinavia. A Swedish-Norwegian interdisciplinary research-network investigated the most prominent category – the remains of crofts. Due to industrialisation, urbanisation and the modern welfare state, the institution of crofting was abolished, and many crofters left for opportunities elsewhere. The welfare state transformed a landscape of living and working people into a one filled with relicts mostly from the nineteenth century. Although numerous and important to local citizens, these sites fall outside the authorised heritage discourse (AHD) in terms of both research and heritage management. This paper takes an environmental justice perspective to challenge the AHD. Three themes are in focus: (1) bringing out the history of a subaltern and marginalised group of people; (2) promoting crofts as heritage of importance to local citizens and demanding complex management due to the various historical narratives and risks; (3) considering the crofting landscapes in relation to the (economisation) framing of heritage in development processes, especially in relation to fair development in present rural communities. 相似文献
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Hans Esselborn 《Revue de synthèse / Centre international de synthèse》1996,117(3-4):441-460
With the help of Luhmann’s theory, this essay tries to define the connection between the boom of autobiographical writing in the late 18th century and the rise of the middle classes. Central to this, is his definition of “career”, with which he describes the individuals’ behaviour in the new functional bourgeois society. Strictly speaking, the individual gains personal and social identity, through his or her spoken or written autobiography as can be seen clearly in Jung-Stilling’s autobiography, which was published bit by bit. The individual hereby improves its prospects of social advancement. On the other hand, K. P. Moritz in hisAnton Reiser describes his hero’s life as the “career” of a failure whose hyperactive imagination interferes with the formation of his identity. Thus autobiographical writing in the 18th century shows itself as the literary autopoiesis of the authors’ concrete individuality. 相似文献