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Gary Bridge 《Geoforum》2008,39(4):1570-1584
This paper explores the radical possibilities of pragmatism for geography using the illustration of arguments concerning a renewed (urban) public realm through the exchange of validity claims in communication. Pressing further the pragmatist possibilities of Habermas’s idea of communicative action it draws on John Dewey’s work, and a range of contemporary pragmatist philosophers, to consider human communicability in its widest sense. This is then explored using an example of the spatiality and performativity of body-minds in a range of communicative spaces of the city. Then the paper moves on to consider the radical implications of pragmatism for geography in general in terms of body-mind/environment relations; a transactional view of space; experience, rationality and radical democracy.  相似文献   
2.
张翼飞  赵敏 《地球科学进展》2007,22(11):1141-1149
意愿价值评估法(CVM)以新古典经济学需求理论为基础,通过构造假想市场使生态服务价值的评估成为可能.但是,经验研究中出现了与新古典经济理论及其预期不一致的异常现象,致使CVM的有效性与可靠性受到广泛质疑,而成为目前国际CVM研究的主要方向.对国际、国内CVM有效性与可靠性的研究进展进行了综述,重点梳理了国际上对WTP的内容依赖性、WTP与WTA的显著差异及可靠性与效益转移等方面的经验研究;而国内由于缺乏该方面的系统研究,制约了CVM在我国生态价值评估及环境公共政策制定中的应用.为此,在前期开展的实例研究基础上,设计了适合我国社会经济特征和生态环境特点的CVM有效性与可靠性研究的技术路线和多重调查方案,以期推动CVM在我国的进一步发展与应用.  相似文献   
3.
铜陵矿区水系沉积物中重金属存在形态特征研究   总被引:11,自引:0,他引:11  
通过对铜陵水系沉积物重金属形态分析实验,研究了重金属各种形态在沉积物中分布特征。分析结果显示,矿区水系沉积物中Cu、Pb、Zn、Cd等重金属含量都显著的高于对照样品,水系已经受到重金属的污染。提出了防治和改善铜陵地表水环境污染的措施。  相似文献   
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区域创新系统的运行融合了区域经济发展的各个主体,促使创新资源在各个主体间流动,并最终产生知识的创新与成果的转化。但由于创新环境的不完善,这个过程中存在着市场失效的的现象。导致创新资源有时并不按照市场的规则来执行资源的分配与利用。本文运用Topsis法,在考虑环境对创新系统的影响下对中部六省各个区域创新系统的有效性运行进行了分析。  相似文献   
5.
在辽宁沿海经济带发展战略环评中,运用数据包络分析(DEA)方法进行港城一体化发展量化评价。评价结果表明:锦州属于“双有效城市”,丹东和盘锦属于“双无效城市”,营口属于“港口有效城市”,大连和葫芦岛属于“城市有效城市”。根据量化结果提出港口统筹规划、临港产业带动城市发展、港城可持续发展等港城一体化发展对策。  相似文献   
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l.Intr0ducti0nTheequationsgoverningthemotionsoftheatmosphereandoceanaren0nlinear0nes.Itisdiffcultandcomplicatedtodealwiththenonlinearproblem.Sothetangentlinearmodel(TLM),whichisobtainedbylinearizingthenonlinearmodelinthevicinityofthebasicflow.iswidelyutilizedinthetheoreticalresearchandpracticalimplementationintheatmosphericandoceanicsciences.First-TLMcanbeusedtoestimatetheev0luti0nofsmallPerturbati0nsinaf0recastmodel.Second,itisadoptedinextendedKalmanfilterinthedataassimilation(Evensen,l99…  相似文献   
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Unbonded flexible pipe is one of the important pieces of equipment in floating production systems for transport of oil and gas between floaters and subsea wells located in deep water. To assure safety over a long-term service period, analysis of fatigue behavior under alternative bending is a key requirement. An analytical model for prediction of bending behavior is essential for understanding the mechanism of the local stress distribution in the helical wires of the tension armor layers under alternative curvatures and rapid estimation of the service life of flexible pipes for designers in engineering practice. In this paper, seven analytical models available in the literature are selected and summarized. Although the experimental results reported in the literature are limited, a three-dimensional finite element model is developed for investigation of the seven models, and the validity and limitations of these models for different structural parameters of helical wire are discussed, i.e., the width-thickness ratio of the wire section and helical angle. The analytical model based on spring theory resulted in a satisfactory estimation of bending stress for most cases and is recommended as a tool for the basic design of the helical armor wire structures in flexible pipes.  相似文献   
8.
The Kuwaiti desert is swept by strong winds, particularly by northwesterly wind, during the summer months (April through September), causing mass-scale sand transport that poses a serious environmental hazard. Understanding that accurate transport rate data are very difficult to obtain either by field measurements or by using any existing sand transport formulae, this paper presents a mathematical model to predict the sand-transport rate for Kuwaiti desert by following a well-known theoretical approach of Lettau and Lettau (1978) and by taking into account the effect of seasonal wind variability. The validity of the model is next examined using the field data from the study of Al-Awadhi and Al-Sudairawi (2002). The examination showed that the model underestimates the rate of sand transport by an average ratio of 0.15. The application of the model, at some seven locations that are evenly distributed across the Kuwaiti desert, indicated that about 40% of the amount of sand transport in Kuwait prevails from the NW during the peak summer months (June and July). The resulting map of sand transport rate indicated that the zone of higher sand transport rate is located within the areas covered by most extensive mobile sand sheets and sand dunes.  相似文献   
9.
Participatory mapping in social research is characterized by methodological pluralism, with two common methods being qualitative mapping using stakeholder interviews and quantitative methods that engage larger public samples through digital, internet mapping. To date, there has been no systematic evaluation of the extent to which mixed methods in participatory mapping yield valid results when applied to the same research setting and research questions. A mixed methods research design (combined exploratory sequential and convergent parallel) was implemented in a large research project to identify marine and coastal values in the Kimberley region of Australia. Qualitative interviews (n = 167) were completed with stakeholders to identify place-based values using polygon mapping methods and internet-based public participation GIS (PPGIS) methods (n = 578). We defined and operationalized the concepts of concurrent, commensurate, and convergent validity to assess mixed methods research outcomes. We found that qualitative and quantitative methods resulted in moderate to high concurrent validity when assessing the importance of place values in the study area. Convergent validity (spatial) was highly variable by place value, with stronger convergent validity found with mapped aesthetic, recreational fishing, tourism, biodiversity, and Aboriginal culture values, and weakest with existence, therapeutic, and commercial fishing values. Convergent validity was influenced by weak commensurate validity through the use of different geometric features (polygons versus points) for mapping values across a large study area. The utility of mixed methods for planning decision support in a convergent parallel design depends on demonstrating convergence in construct meaning, spatial location, and consistency in values in the sampling populations.  相似文献   
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