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根据产业经济学的观点,提出我国地理信息产业目前处于产业扩张阶段的观点,推动产业规模迅速扩大成为行业发展的主要目标。由于派生性特点,寻求地理信息的本源性需求是产业完成扩张的关键问题,利用地理信息反映的价格信息支持社会公众经济博弈活动将是地理信息巨大的本源性需求。本文建议在产业扩张阶段应当瞄准社会公众、探索对公众生活进行博弈支持的服务方式。 相似文献
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加强地理信息资源建设和开发利用的思考 总被引:1,自引:0,他引:1
地理信息资源的建设和开发利用在准确掌握国情国力、提高管理决策水平、管理社会公共事务、处理经济社会发展等重大问题中将发挥越来越重要的作用。本文在对发改委、测绘、国土、环境保护等部门进行调研的基础上,从我国地理信息的获取和利用现状、地理信息资源建设和开发利用政策法规的制定、产业发展以及国家安全等四个方面进行了研究,并提出了建议。 相似文献
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Yalchin Efendiev Akhil Datta-Gupta Xianlin Ma Bani Mallick 《Mathematical Geosciences》2008,40(2):213-232
In this paper, the Markov Chain Monte Carlo (MCMC) approach is used for sampling of the permeability field conditioned on
the dynamic data. The novelty of the approach consists of using an approximation of the dynamic data based on streamline computations.
The simulations using the streamline approach allows us to obtain analytical approximations in the small neighborhood of the
previously computed dynamic data. Using this approximation, we employ a two-stage MCMC approach. In the first stage, the approximation
of the dynamic data is used to modify the instrumental proposal distribution. The obtained chain correctly samples from the
posterior distribution; the modified Markov chain converges to a steady state corresponding to the posterior distribution.
Moreover, this approximation increases the acceptance rate, and reduces the computational time required for MCMC sampling.
Numerical results are presented. 相似文献
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James L. Coleman Jr. 《Natural Resources Research》1995,4(3):273-288
The American whaling industry rose from humble beginnings off Long island to become an international giant. In its peak year, 1846, 735 ships and 70,000 people served the industry. As whale stocks and reserves decreased, whalers were forced to go farther and farther from their New England home ports. Voyages became longer, and risks on required return-on-investment became higher. The easy money of Atlantic and Pacific whaling was no more: the only remaining profitable ventures were to Arctic and Antarctic waters. Many ships returned empty, if at all. in 1871, most of the Arctic whaling fleet was crushed by early winter ice and lost. This calamity, in conjunction with the long-term diminishing whale stocks, the diversion of investment capital to more profitable ventures, and the discovery, development, and refinement of abundant petroleum crude oil, struck the death blow to the American whaling industry. By 1890, only 200 whaling vessels were at work, and by 1971, no American commercial whaling ship sailed the world's oceans.It is apparent that no single event caused the final, rapid decline. However, a single calamity, in an already stressed industry, that was self-insured and commercially interlinked, precipitated the end. Today's American petroleum industry, although adopting some principles of the American whaling industry, also has embraced other activities such as work process reengineering and customer alliances, which may preempt, or postpone, a similar catastrophic demise. 相似文献
17.
甘军丽 《云南地理环境研究》2006,18(2):100-103
基于建立泛珠三角的研究背景,通过对广州发展工业旅游的条件的分析得出结论,认为由于地缘关系和历史原因,在泛珠三角的成员中,广东最早接受香港地区的经济辐射,港澳台投资者在广东大量投资建厂,工业优势也日渐凸显,这种得天独厚的优势,为广东发展工业旅游奠定了坚实的基础。并通过对广东工业旅游示范点和其他适合发展工业旅游的企业进行调查分析和实证研究,总结了广东发展工业旅游的主要客源类型,并对广东工业旅游的发展提出了几点发展思路。工业与旅游相结合,两者完全可以达到双赢,并可以得到一定的社会效益,也是结论性认识。 相似文献
18.
运用可拓工程方法和主成分分析方法建立了福建省第三产业发展水平的综合评判物元模型。模型的输出结果表明:福建省各地区第三产业发展水平差距悬殊;综合关联度将第三产业发展水平划分成4个等级,单指标关联度则揭示了各地区第三产业发展的优、劣势。 相似文献
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Local food is championed as one alternative response to industrial systems of food production and supply. While advocacy for local food is high, there is a lack of empirical evidence about the actual shape and scale of such food supply chains, especially from a retail perspective. Using supply chain diagrams, this paper presents a summary of ‘new’ agro-food geographies for five different retail types—farm shops, butchers, caterers, specialist shops, supermarkets/department stores—that all source local food from suppliers in the Scottish-English borders. Presented as five separate ‘shopping trips’, the paper examines where, how and why retailers source local food. Results reveal the complex nature of local food systems, especially in terms of intra-sector competitive dynamics (with a notable tension between direct forms of retail and established (independent) retailers), links and overlaps with ‘normal’ food retail systems and elastic notions of the ‘local’. The paper also draws a key distinction between locally produced and locally supplied food products. 相似文献