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101.
《Marine Policy》2017
Over the past decade, fisheries learning exchanges (FLEs), in which representatives from different fisher communities come together to share marine conservation challenges and solutions, have been produced by a range of non-government organizations (NGOs) and federal agencies. This paper presents an overview of the history and scope of FLEs. A literature review, questionnaire, expert workshop, and key informant interviews were conducted. A content analysis was performed of the key informant interviews using a grounded theory approach. This paper offers a formal definition of a FLE, describes different configurations of FLEs, discusses the utility, common objectives, and common outcomes of FLEs, and outlines a research agenda for future work on FLEs. Organizers have found FLEs to have four main utilities: 1) FLEs leverage peer-to-peer sharing so that participants open each other's horizons for improving fisheries and fishing 2) FLEs catalyze and speed change, 3) FLEs are good for sharing thoughts that are difficult to receive and accept, 4) FLEs facilitate involvement and commitment from relevant parties needed for change. The most commonly documented purposes of FLEs were related to marine reserves, fisheries management strategies, bycatch reduction, and alternative livelihoods to fishing. The most common objectives among the FLEs surveyed were to encourage action or behavior, to openly exchange ideas, and to introduce new technology. As a result of FLEs the common outcomes were that participants were inspired to make changes, new programs were implemented, relationships were built and connections made, and participants enhanced their understanding of marine management strategies. 相似文献
102.
Spatial and temporal knowledge representation 总被引:1,自引:1,他引:0
Antony Galton 《Earth Science Informatics》2009,2(3):169-187
Knowledge Representation (KR) originated as a discipline within Artificial Intelligence, and is concerned with the representation
of knowledge in symbolic form so that it can be stored and manipulated on a computer. This article surveys that part of KR
that is concerned with the representation of space and time, with particular reference to the use of such representations
in geographical information science.
相似文献
Antony GaltonEmail: |
103.
104.
我国知识集约型可持续农业的发展机制研究 总被引:2,自引:1,他引:2
阐述了知识集约型可持续农业的理论内涵和本质特征,论述了知识集约型可持续农业是我国的必然选择和未来希望,并通过深入剖析我国农业知识化程度低下的现状特征及形成原因,具体地提出了我国知识集约型可持续农业的发展机制。 相似文献
105.
Attitudes to Geography in Australia 总被引:1,自引:0,他引:1
R. V. Gerber 《The Australian geographer》2001,32(2):221-239
This article reports on an initial study in Australia of attitudes to geography held by members of the community at large. The study focused on perceptions of the role of geography in contributing to wider social goals relating to lifelong learning and living. Groups of business people, government representatives, professional people, educators and members of the general public were surveyed. The results focus on the perceptions of the importance of geography to Australian society; important knowledge, skills and values that are learned while doing geography; and the importance of geography for work. The generally positive appreciation of geography that is held by the wider community needs to be promoted carefully in the education sectors and in society at large if geography is to live up to the importance that is ascribed to it. 相似文献
106.
Corporate knowledge transfer via interlocking directorates: a network analysis approach 总被引:1,自引:0,他引:1
This paper explores spatial changes to knowledge transfer by Canadian and American corporate networks from 1976 to 1996. Results support facets of a World Cities approach for Canada. Toronto lies at the top of the hierarchy, while Montreal, Calgary, and Vancouver fall into a third tier of specialized regional cities. The American knowledge network also possesses facets of the world cities approach. The world city, New York, lies at the top of the hierarchy. Further down, Chicago is a specialized national city, while a number of regional centers have emerged to play a larger role over the twenty-year study period. A third tier of cities has emerged to play the critical role of specialized regional cities. This geographical phenomenon can be explained in terms of industry, headquarters locations, and network maturity. Finance, insurance and real estate, as well as “other manufacturing” are three sectors of the economy that are prominent in the network. In Canada, these sectors have increasingly centralized in Toronto while decentralizing in the United States. Similarly, the headquarters location of American firms is decentralizing from New York and Chicago, while Canadian headquarters continue to be centralized in Toronto. Finally, results indicate that the potential for knowledge transfer depends upon maturity of the system under investigation. The mature US network with a large pool of qualified business individuals is better suited for knowledge transfer at the regional level. The Canadian network is less developed and not appropriate for regional systems of knowledge transfer. The result is a Canadian corporate knowledge threshold that encompasses the entire country while a number of much smaller corporate knowledge thresholds appear across the United States. 相似文献
107.
This paper presents an account of the progress of the integration between the Danish and Swedish parts of the Öresund Region within the world of science, with emphasis on biotech. The paper is based on data from the database Science Citation Index Expanded. The amount of co-authorships produced by agents from each side of the region is analysed for a 12-year period (1994–2005) and used as an indicator to show how the integration is proceeding. Each of the co-authorships is examined to shed light on the nature of the interactions, thereby identifying the agents most involved in collaboration. Furthermore, the development in co-authorships within the region is compared to the development in co-authorships between the Öresund Region and four selected reference areas. Our findings indicate that there has been a substantial increase in both the number of co-authorships overall and within biotech solely. The rise in co-authorships between the two parts is proceeding at a faster pace than the rise in co-authorships between the Öresund Region and the reference areas. The overall results of this paper indicate a growing integration of the biotech sector in the Öresund Region. 相似文献
108.
Neil Wrigley 《Geoforum》2006,37(3):340-351
This paper examines the organizational challenge of e-commerce for emerging retail transnational corporations (TNCs). The paper begins by scoping and conceptualizing the retail TNCs and in the process, draws attention to the high level of territorial embeddedness of these firms. This provides the framework for the remainder of the paper, where the organizational challenge of a ‘multi-channel’ paradigm (blending online and offline forms of retail distribution) is evaluated. Specifically, the paper argues that place, space and embeddedness continue to matter in the ‘new e-conomy’ of multi-channel distribution. 相似文献
109.
经对多个滑坡体勘察实践,结合前人研究成果,对滑动带(面)的确定,滑带土抗剪强度指标的选取,稳定性计算中易被忽视的问题进行探讨。 相似文献
110.
Rafi Baker George Christakos 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(4):435-446
The well-known “Maximum Entropy Formalism” offers a powerful framework for deriving probability density functions given a
relevant knowledge base and an adequate prior. The majority of results based on this approach have been derived assuming a
flat uninformative prior, but this assumption is to a large extent arbitrary (any one-to-one transformation of the random
variable will change the flat uninformative prior into some non-constant function). In a companion paper we introduced the
notion of a natural reference point for dimensional physical variables, and used this notion to derive a class of physical
priors that are form-invariant to changes in the system of dimensional units. The present paper studies effects of these priors
on the probability density functions derived using the maximum entropy formalism. Analysis of real data shows that when the
maximum entropy formalism uses the physical prior it yields significantly better results than when it is based on the commonly
used flat uninformative prior. This improvement reflects the significance of the incorporating additional information (contained
in physical priors), which is ignored when flat priors are used in the standard form of the maximum entropy formalism. A potentially
serious limitation of the maximum entropy formalism is the assumption that sample moments are available. This is not the case
in many macroscopic real-world problems, where the knowledge base available is a finite sample rather than population moments.
As a result, the maximum entropy formalism generates a family of “nested models” parameterized by the unknown values of the
population parameters. In this work we combine this formalism with a model selection scheme based on Akaike’s information
criterion to derive the maximum entropy model that is most consistent with the available sample. This combination establishes
a general inference framework of wide applicability in scientific/engineering problems. 相似文献