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3D electrical resistivity inversion using prior spatial shape constraints 被引量:8
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作者 李术才 聂利超 +4 位作者 刘斌 宋杰 刘征宇 苏茂鑫 徐磊 《Applied Geophysics》 SCIE CSCD 2013年第4期361-372,510,共13页
To minimize the number of solutions in 3D resistivity inversion, an inherent problem in inversion, the amount of data considered have to be large and prior constraints need to be applied. Geological and geophysical da... To minimize the number of solutions in 3D resistivity inversion, an inherent problem in inversion, the amount of data considered have to be large and prior constraints need to be applied. Geological and geophysical data regarding the extent of a geological anomaly are important prior information. We propose the use of shape constraints in 3D electrical resistivity inversion, Three weighted orthogonal vectors (a normal and two tangent vectors) were used to control the resistivity differences at the boundaries of the anomaly. The spatial shape of the anomaly and the constraints on the boundaries of the anomaly are thus established. We incorporated the spatial shape constraints in the objective function of the 3D resistivity inversion and constructed the 3D resistivity inversion equation with spatial shape constraints. Subsequently, we used numerical modeling based on prior spatial shape data to constrain the direction vectors and weights of the 3D resistivity inversion. We established a reasonable range between the direction vectors and weights, and verified the feasibility and effectiveness of using spatial shape prior constraints in reducing excessive structures and the number of solutions. We applied the prior spatially shape-constrained inversion method to locate the aquifer at the Guangzhou subway. The spatial shape constraints were taken from ground penetrating radar data. The inversion results for the location and shape of the aquifer agree well with drilling data, and the number of inversion solutions is significantly reduced. 展开更多
关键词 electrical resistivity INVERSION prior spatial constraints direction vector GEOPHYSICS geotechnical engineering.
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新型粉笔
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作者 吴秋实 《企业科技与发展》 1995年第12期12-12,共1页
粉笔是具有多年历史的简易书写工具,它使用方便、价格低廉,应用极为广泛。但由于其使用过程中产生粉尘较多,被吸入体内不利身体健康、同时粉笔末易于飞散,对环境也会造成污染。这里介绍一种新型粉笔,它具有与普通粉笔相似的外型和功能,... 粉笔是具有多年历史的简易书写工具,它使用方便、价格低廉,应用极为广泛。但由于其使用过程中产生粉尘较多,被吸入体内不利身体健康、同时粉笔末易于飞散,对环境也会造成污染。这里介绍一种新型粉笔,它具有与普通粉笔相似的外型和功能,书写流利,字迹易于擦掉,且几乎不产生粉尘,可以在很多场合替代通常所用的粉笔。 这种粉笔由球状物质、微粉物质、蜡状物质、润滑剂及颜料等诸成分组成。作为粉笔主体成分之一的球状物质是平均粒径为80微米的球状颗粒,可选用白炭黑、氧化铝等无机物,也可选用聚丙烯酸树脂、密胺树脂、酚醛树脂、聚乙烯树脂等有机聚合物。 展开更多
关键词 球状物质 聚丙烯酸树脂 氧化铝 平均粒径 粉笔 重量百分数 硬脂酸钙 酚醛树脂 液体石蜡 白炭黑
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Thermodynamic behavior for generalized f(R) gravity with arbitrary coupling between matter and geometry
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作者 WU YaBo ZHAO YueYue +3 位作者 LU JianBo ZHANG Xin TONG HaiDan YANG Hao 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第12期2331-2337,共7页
The thermodynamic behavior of field equations for the generalized f(R) gravity with arbitrary coupling between matter and geometry is studied in the two kinds of spacetime,i.e.,the both spatially homogenous,isotropic ... The thermodynamic behavior of field equations for the generalized f(R) gravity with arbitrary coupling between matter and geometry is studied in the two kinds of spacetime,i.e.,the both spatially homogenous,isotropic FRW universe and static,spherically symmetric black hole spacetime.The field equations of the generalized f(R) gravity with arbitrary coupling between matter and geometry can be cast to the form of the first law of thermodynamics with the reputed entropy production terms dS,which are quite general and can degenerate to the cases of Einstein's general relativity and pure f(R) gravity with non-coupling and nonminimal coupling as special cases.The appearance of the entropy production term dS illustrates that the horizon thermodynamics is non-equilibrium one for the generalized f(R) gravity with arbitrary coupling between matter and geometry. 展开更多
关键词 f(R) gravity THERMODYNAMICS black hole FRW universe
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