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例说连贯性思维在解一题多问型问题时的重要作用
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作者 娄正凯 《新高考(高三语文、数学、英语)》 2011年第4期43-43,共1页
我们先来看下面一道试题.在边长为α菱形ABCD中.LABC=60°.PC⊥平面ABCD,PA=2AB,E,F分别是PA和AB的中点。(1)求证:BD⊥PA;(2)求证:EF∥平面PBC;(3)求三棱维E-PBC的体积。
关键词 一题多问 连贯性 PBC 三棱维 平面 菱形 边长
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立体几何中常用的基本图形
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作者 周彩霞 《数学教学研究》 2001年第3期9-11,共3页
关键词 立体几何 基本图形 空间四点 三棱维 二面角
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点面距离,一招三式
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作者 张良强 《数学学习与研究(初中)》 2003年第1期19-21,共3页
关键词 点面距离 立体几何 等积转化 三棱维 平行转化 线面平行模型 比例转化 线面相交模型 例题 题解
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An automatic unified modeling method of geological object and engineering object based on tri-prism(TP) 被引量:1
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作者 张荣春 李浩 +1 位作者 吴铭飞 王亚芹 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1419-1426,共8页
For the interaction relation between geological object and engineering object in some fields related to water conservancy and hydropower, a unified modeling idea was proposed. On the basis of summarizing both advantag... For the interaction relation between geological object and engineering object in some fields related to water conservancy and hydropower, a unified modeling idea was proposed. On the basis of summarizing both advantages and disadvantages of existing modeling methods, an automatic unified modeling method of both engineering and geological objects based on tri-prism(TP) model was presented. Through the lossless correction algorithm of deviated drill holes contained in this method, the real deviated drill holes could be corrected into the equivalent virtual vertical ones. And the correction accuracy fully meets the requirements of unified modeling. With the virtual vertical drilling data, TIN construction of both cover layer and other stratums would be built in order to obtain the 3D geological model. Then, the engineering design data would be introduced into the 3D geological model for achieving unified modeling. For this process, the volume subdividing and restructuring principles were introduced to deal with the spatial relationships between engineering object and geological object. In order to improve the efficiency of unified modeling, the reconstruction of TIN based on constraint information was also applied in this method. At last, the feasibility and validation of the unified modeling method as well as its relevant key algorithms were verified by specific experiments and analysis of results. 展开更多
关键词 tri-prism(TP) model unified modeling deviated drill holes correction volume subdividing constraint information
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A three-dimensional matching localization algorithm based on helix triangular pyramid array
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作者 ZHAO Jiu-bin LIU Yuan-xue +1 位作者 LIU Chang-jia LING Yue 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第3期816-833,共18页
On the eve of the occurrence of geological hazards,part of the rock and soil body begins to burst,rub,and fracture,generating infrasound signals propagating outward.3D advanced positioning of the landslide has remaine... On the eve of the occurrence of geological hazards,part of the rock and soil body begins to burst,rub,and fracture,generating infrasound signals propagating outward.3D advanced positioning of the landslide has remained unsolved,which is important for disaster prevention.Through the Fourier transform and Hankel transform of the wave equation in cylindrical coordinates,this work established a three-dimensional axisymmetric sound field model based on normal waves,and designed a 4-element helix triangular pyramid array with vertical and horizontal sampling capabilities.Based on this,the three-dimensional matching localization algorithm of infrasound for geological hazards is proposed.Applying the algorithm to the infrasound signal localization of rock and soil layers,it was found that the helix triangular pyramid array can achieve accurate estimation of depth and distance with a smaller number of array elements than the traditional array,and may overcome the azimuth symmetry ambiguity.This study shows the application prospects of this method for predicting geohazards position several hours in advance. 展开更多
关键词 geologic hazards INFRASOUND helix triangular pyramid array 3D matchinglocalization algorithm
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