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通过对2009—2012年度临沂市9县3区统计年鉴和变更调查中11个相关指标数据的搜集,借助MATLAB7.0软件平台,利用BP人工神经网络算法,算出2009—2012年度各县区土地利用集约度,并利用BP人工神经网络的预测功能,预测了2013年和2014年度土地利用集约度值,结果表明临沂市平均土地利用集约度水平正逐步从粗放利用发展到中度集约,兰山区土地利用集约度水平一直为高度集约,集约度居全市之首,罗庄区一直为中度集约,稳中有进。预计到2014年底,大部分县区在中度集约或以上,仅有费县、蒙阴2县为粗放利用。。 相似文献
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A numerical method of statistical pattern recognition is proposed in this paper. Different from the discriminatory analysis method currently used in the mathemalic statistics, it is unnecessary to assume that the predictand should be subject to a certain distribution. On the contrary, the statistical relationship between predictand and predictor has been obtained directly with computer according to actual distribution to recognize the category of patterns. Result of forecast has been improved as compared with the usual analytic discriminatory method. The influence of predictor on predictand can be seen clearly from this method and the transparency is good. Therefore, it is better to use the method in very short range forecast for which causality is more obvious. 相似文献
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以临沂市兰山区李官镇为例探讨了土地利用类型结构的分维特征,讨论了分维值与土地利用复杂性和稳定性的关系。经研究,李官镇土地利用结构具有分形特征,人为因素对农村道路、沟渠和有林地的影响突出,使得这3种土地利用类型结构呈现复杂化和不规则化,在以后的规划中应以合理规划农村道路,合理布局沟渠和有林地为主要思路,为土地利用科学规划提供辅助决策。 相似文献
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混凝土表面缺陷处理的施工质量,主要取决于修补材料的正确选用和修补工艺的正确操作。修补材料主要包括表层缺陷修补材料、混凝土表面保护和浅层修补材料及孔槽填补材料;工艺优化主要包括湿润养护工艺优化、大面积修补工艺优化、小孔洞填补工艺优化、大孔洞填补工艺优化。三峡大坝三期工程混凝土表面缺陷处理的修补材料,都经过推荐、调查、室内... 相似文献
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This paper describes a geopotential thickness difference method for computing instability energy E. EP1P2 =g0 ( ΔHsP1P2-ΔHP1P2 , where ΔHP1P2 is the geopotential thickness of P1-P2 level; ΔHsP1P2 is called adia-batic geopotential thickness, based on which a computational method for high resolution of instability energy is proposed. E(x,y)≈g0(A(x,y) - B(x,y)), where A is interpolating polynomial of ΔHSP2P2 and it is afunction ofθe, of surface observing stations (x, y); B(x,y) is the thickness over corresponding stations (x, y) obtained using surface fitting method. Therefore, data of METAR can be used by computer to produce hourly horizontal distribution chart of E of surface observing station density. With the result that the temporal and spatial resolution of stability analysis has been improved. Practical use has shown that this method is an effective tool for very short range forecast of severe convective storms. 相似文献
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