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71.
In Part I of this paper (Smith and Hsieh, 1997) a programming formulation of steady states was developed for gravity-type interactive Markov chains in terms of their associated spatial-flow chains. These results are here applied to analyze the stability properties of interactive Markov chains. In particular, the objective function for this programming formulation is shown to constitute a Lyapunov function for an appropriately defined continuous-time version of spatial-flow chains. The Lyapunov stability properties of these spatial flows are then shown to yield corresponding stability properties for the continuous-time versions of interactive Markov chains. In particular, these processes always exhibit global convergence to steady states. Finally, it is shown that when steady states are unique, these convergence results are inherited by those interactive Markov chains that are 'sufficiently close' to their continuous-time versions. 相似文献
72.
This paper explores attempts to establish a network of firms and organizations to develop the multimedia industry at a regional level. The paper sets out its review in the context of the regional economy, and then details the nature of the networking process under investigation. An evaluation of networking in this context is provided, based on detailed empirical research. Lessons are drawn from the experiences of seeking economic modernization through organizational networks. 相似文献
73.
Strategic planning, as developed in the military and business sectors, offers a procedural model with important differences from the earlier comprehensive approach. Economic and physical development strategies, often called for by national planning legislation in European countries, frequently have little in common with the model proposed by Steiner for private firms, or espoused for the public sector by Bryson and others: there appears to be confusion resulting from use of similar terms. This paper investigates efforts to employ at least the major features of strategic planning in two institutionally and culturally different contexts, nearly half a world apart. In Bergen, Norway, these principles have informed economic development planning and planning for a major district of the city. In the case of Seattle, Washington, USA, the new comprehensive plan is based on framework policies developed during a 2‐year public process, and now that the city‐wide plan is adopted, Seattle is turning to developing neighbourhood plans which will provide more operational detail for guiding public and private investments. Comparison of these two cases both provides contrasts and similarities stemming from the two different contexts, and help to evaluate the transférability of strategic planning from the private to the public sector. 相似文献
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Environmental limitations on prehistoric pastoralism in Africa 总被引:1,自引:0,他引:1
Andrew B. Smith 《African Archaeological Review》1984,2(1):99-111
In several areas of Africa, pastoralism that existed prehistorically no longer survives today. Two such areas, the Southwestern Cape of South Africa and the Sahara, are discussed here, outlining methodologies for reconstruction of adaptive strategies on the basis of environmental parameters that constrained the pastoral economies.
Résumé En plusieurs régions d'Afrique, le pastoralisme qui existait en temps préhistorique a maintenant disparu. L'article discute de deux de ces régions, le cap sud-ouest de l'Afrique du Sud et le Sahara, donnant un aperçu des méthodologies qui visent la reconstruction des stratégies adaptatrices en se fondant sur les paramètres écologiques qui ont contraint les économies pastorales.相似文献