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31.
运用德尔菲调查—灰色统计法确立水库鱼产力综合评价中的指标权重体系 总被引:1,自引:0,他引:1
本文运用德尔菲方法对水库鱼产力综合评价中指标权重的合理分配问题作了专家调查,并采用灰色统计法对调查结果进行归纳处理,从而确立了一个水库鱼产力影响因素诸层次各方面的评价指标权重体系,可供今后的评价工作参考使用。 相似文献
32.
Two commonly used methods of simulating random time series, given a target power spectrum, are discussed. Wave group statistics, such as the mean length of runs of high waves, produced by the different simulation schemes are compared. The target spectra used are obtained from ocean measurements, and cover a wide range of ocean conditions. For a sufficiently large number of spectral components, no significant differences are found in the wave group statistics produced by the two simulation techniques. 相似文献
33.
海冰板的环形屈曲的压缩破坏 总被引:2,自引:0,他引:2
在轴对称条件下,给出海冰板的环向屈曲面临载荷,从细观力学的观点分析了微裂纹开裂的条件,扩展方向并给出绕海洋平台柱腿冰的损伤区的尺度。所给出的临界半径是一个与冰材料力学特征,冰的微结构参数一海洋平台柱腿半径相关的特征参数。对现场所观察和测量的结构给出了解释和定量分析。 相似文献
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36.
Open source, spatial analysis, and activity-travel behaviour research: capabilities of the aspace package 总被引:2,自引:0,他引:2
This paper reports on recent experience with the development of aspace, an Open Source (OS) library for the geographic visualization and analysis of activity-travel behaviour. The paper begins
with an overview of recent progress with respect to the convergence of Open Source technology, spatial analysis, and travel
behaviour research. The remainder of the paper focuses on aspace; a collection of functions that, when combined with data describing the geographical location of daily activities, can be
used to visualize and describe spatial properties of individual and household activity spaces. These properties include: size,
orientation, shape, and the geographical dispersion of activity locations contained within the activity space. Several planar
geometries are used to transform measurable spatial properties into intuitive objects for visualizing spatial patterns of
activity participation. Experiments are conducted, using data from the first wave of the 2003 Toronto Travel Activity Panel
Survey, to demonstrate the potential application of aspace for basic and applied policy-based research into activity-travel behaviour. The toolkit is distributed as a downloadable
‘package’ from the Open Source R Project for Statistical Computing.
相似文献
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本文在解放军土地管理局研制的“军用土地管理信息系统”的基础上,从系统设计和应用的角度出发,明确了系统应包括的基本功能,提出了改进和完善系统的方法。 相似文献
39.
A geochemical evaluation of the Szc-Halimba-Kisld area, Hungary, covering an area of more than 200 km2 is presented using different statistical and geostatistical methods. The study area is a representative example of allochtonous karst bauxite accumulation. The three groups of deposits studied here have been explored and mined since 1950. Several thousand boreholes have been drilled, and bauxite cores were analyzed for the five main chemical components. A total of 80,000 pleces of analytical data were processed, followed by a geological examination of borehole logs and of mining excavations.The quantitative geochemical evaluation of the data set led to both geochemical and practical results: The geochemical behavior of the allochtonous, clastic karst bauxite deposits differs essentially from that of the autochtonous and parautochtonous ones, as well as that of the lateritic bauxite deposits. The deposits of the study area can be split into several subsequent geochemical-sedimentological units, each representing an event of bauxite transport and accumulation. Clear regional patterns can be revealed in the composition of these units. The geostatistically measured chemical variability of the geochemical units is rather different, the lowest units showing the smallest variability. The interrelations of the main chemical components are weaker and more irregular in the studied deposits than in the autochtonous lateritic bauxite deposits. Additional local genetic features, such as transport routes, can be delineated by the methods applied. Within each deposit, local changes of chemical composition and of its variability can be determined more precisely. These results can be used in bauxite prospecting and exploration, because areas of high or low bauxite quality can be predicted. 相似文献
40.
有关循环经济下农业政策法制建设的探讨 总被引:1,自引:1,他引:1
蒋小翼 《云南地理环境研究》2006,18(1):79-82
如今,发展循环经济,建立循环型社会已经成为世界各国的潮流和趋势。在中国,要想发展循环经济,必须在各个产业逐步建立起与之相支持的文化、法律、政策、经济和生态体制。中国是一个农业大国,发展循环农业经济建设,无论对循环经济的发展和循环型社会的形成还是对农业经济的发展都具有重要意义。从中国现阶段农业政策法制状况出发,借鉴国外的先进经验,探讨在农业方面实现循环经济的可能性和必要性以及如何完善中国农业制度来适应这一新兴理念。 相似文献