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131.
Kun Zhang Shawn William Laffan Songlin Zhang 《International journal of geographical information science》2013,27(3):403-416
The highly skewed sex ratio at birth (SRB) in China has stimulated numerous studies. However, the geographic distribution of SRB is seldom investigated, particularly at the county level. The need for an understanding at this level has increased since the Chinese government initiated its ‘Care for Girls’ campaign to improve the survival rate of females. This campaign has been initiated in a set of pilot counties. In this article we assess the effectiveness of the set of pilot counties in Shandong province and propose two alternate configurations. To do this, we first assess the spatial distribution of the SRB values by county in Shandong, expressed as a z-score (zSRB) after correcting for the biologically expected SRB value and population size of zero-aged children. A local Moran's Ii analysis of the zSRB values indicates a significant high–high cluster in the southwest of the province. The Ii , zSRB and female deficit (the difference of the observed from biologically expected number of zero-aged females) were then used to define two alternate configurations for the pilot counties. A comparison of the current and alternate configurations against a Monte Carlo randomisation analysis shows that the current configuration is significantly different from a random selection (p < 0.05) for the two criteria of maximising the aggregate female deficit and maximising the zSRB. Although this is a good result, both alternate configurations were more significant (p < 0.001), and therefore represent potentially better configurations for the campaign given the criteria used. The spatial analysis approach developed here could be used to improve the effectiveness of the Care-for-Girls campaign in Shandong province, and elsewhere in China. 相似文献
132.
Wave attenuation and phase velocity dispersion in the temperature domain are more complicated than those in the frequency domain. To describe wave propagation properties in the temperature domain, a so-called thermal activation mechanism model is built on the experimental result that increasing the temperature or decreasing frequency could obtain similar results on the attenuation. A rheological model (the Zener model) is employed to describe viscoelastic attenuation in saturated porous rocks. The Arrhenius relation is introduced to describe the thermal activation mechanism. The wave propagation model with thermal effects in porous media is then obtained, and 1-D P-wave and S-wave propagation characteristics are analyzed in numeric process, respectively.Two attenuation mechanisms are found in this model, the Biot loss and the thermal activation relaxation. The thermal relaxation attenuation peak and the Biot attenuation peak are observed in both frequency and temperature spectra. These two peaks move towards each other when the temperature increases on frequency spectra. The thermal relaxation peak shifts towards higher frequencies while the Biot peak shifts towards lower frequencies. At some temperature, these two peaks will superpose. The combination of the thermal relaxation and the Biot loss leads to the complexity of wave velocity curves. Similar phenomena could be observed on temperature spectra. The thermal relaxation features may relate to a so-called “local heat transfer” mechanism. These two peaks in the temperature domain have been observed in the experiments by other investigators. The characteristics of velocity and attenuation are more remarkable for high porosity rock samples. The model is helpful for the understanding of wave propagation in the temperature domain. 相似文献
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山区沟域经济发展的空间结构GIS分析——以北京市门头沟区为例 总被引:1,自引:0,他引:1
沟域经济是山区发展的新模式,对其空间结构进行研究,可以为山区经济的空间优化和人口、产业布局提供参考,具有理论价值和指导意义.门头沟区位处北京市的山区,其沟域经济发展具有典型性.对此,运用ArcGIS、SPSS软件,采用DEM数据的高程、长度和坡度要素,提取了门头沟区的代表性沟域.在解读门头沟区沟域经济空间结构内涵的基础... 相似文献
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介绍了俄罗斯利用原子弹爆炸获得的长地震剖面资料和利用这些资料对地球的起源和演化的研究成果,以及对不同构造带,如乌拉尔造山带、西伯利亚盆地、科拉半岛、图拉地台和巴仑支海等地区的地壳和上地幔结构及地球动力学过程等方面的研究成果。 相似文献
137.
The data on the coal production and consumption in Jilin Province for the last ten years were collected,and the Grey System GM( 1,1) model and unary linear regression model were applied to predict the coal consumption of Jilin Production in 2014 and 2015. Through calculation,the predictive value on the coal consumption of Jilin Province was attained,namely consumption of 2014 is 114. 84 × 106 t and of 2015 is 117. 98 ×106t,respectively. Analysis of error data indicated that the predicted accuracy of Grey System GM( 1,1) model on the coal consumption in Jilin Province improved 0. 21% in comparison to unary linear regression model. 相似文献
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LIChaokui ZHUQing ZHANGYeting HUANGDuo ZHAOJie CHENSonglin 《地球空间信息科学学报》2004,7(2):135-143
The basic mathematic models, such as the statistic model, the time-serial model, the spatial dynamic model etc.,and some typical analysis methods based on 3DCM are proposed and discussed. A few typical spatial decision making methods integrating the spatial analysis and the basic mathematical models are also introduced, e.g. visual impact assessment, dispersion of noise immissions, base station plan for wireless communication. In addition, a new idea of expectation of further applications and add-in-value service of 3DCM is promoted. As an example, the sunshine analysis is studied and some helpful conclusions are drawn. 相似文献