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ASYMPTOTIC EXPRESSION NEAR THE ELLIPSE OF CONVERGENCE OF JACOBI SERIES IN COMPLEX PLANE
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作者 Mu Lehua(Shandong University, China) 《Analysis in Theory and Applications》 1995年第3期62-71,共10页
In this paper, we shall give an Abel type theorem of Jacobi series and then based on it discuss asymptotic expressions near the ellipse of convergence of Jacobi series in complex plane.
关键词 ASYMPTOTIC EXPRESSION NEAR THE ELLIPSE OF CONVERGENCE OF JACOBI SERIES IN complex plane lim
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Reduced Partition Function Ratio in the Frequency Complex Plane: A Mathematical Approach
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作者 Jie Yuan 《Open Journal of Geology》 2014年第12期654-664,共11页
This paper gives a mathematical approach to calculate the fractionation factor of isotopes in a general cluster (also known as?super-molecule), which composes of necessary chemical effect within three bonds outside th... This paper gives a mathematical approach to calculate the fractionation factor of isotopes in a general cluster (also known as?super-molecule), which composes of necessary chemical effect within three bonds outside the interested atom(s). The cluster might have imaginary frequencies after being optimized in quantum softwares. The approach includes the contribution of the difference, which is resulted from the substitution of heavy and light isotopes in the cluster, of vibrations of imaginary frequencies to give precise prediction of isotope fractionation factor. We call the new mathematical approximation “reduced partition function ratio in the frequency complex plane (RPFRC)”. If there is no imaginary frequency for a cluster, RPFRC?is simplified to be Urey (1947) or Bigeleisen and Mayer (1947) formula. Final results of this new algorithm are in good agreement with those in earlier studies. 展开更多
关键词 ISOTOPE FRACTIONATION Cluster REDUCED PARTITION Function RATIO FREQUENCY complex plane
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On the Kinematics for the Closed Planar Homothetic Inverse Motions in Complex Plane
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作者 Onder Sener Ayhan Tutar 《Journal of Applied Mathematics and Physics》 2017年第5期1120-1129,共10页
In this paper, the Steiner area formula and the polar moment of inertia were expressed during one-parameter closed planar homothetic inverse motions in complex plane. The Steiner point was defined when the rotation nu... In this paper, the Steiner area formula and the polar moment of inertia were expressed during one-parameter closed planar homothetic inverse motions in complex plane. The Steiner point was defined when the rotation number was different zero and it was called the Steiner normal when the rotation number was equal to zero. The fixed pole point was given with its components and its relation between Steiner point or Steiner normal was explained. The sagittal motion of a telescopic crane was considered as an example. This motion was described by a double hinge consisting of the fixed control panel of the telescopic crane and the moving arm of the telescopic crane. The theoretical concepts and results were applied for this motion. 展开更多
关键词 STEINER Formula Polar Moment of INERTIA PLANAR KINEMATICS Homothetic INVERSE MOTIONS complex plane
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Real Hypersurfaces in Complex Two-Plane Grassmannians Whose Jacobi Operators Corresponding to -Directions are of Codazzi Type
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作者 Carlos J. G. Machado Juan de Dios Pérez Young Jin Suh 《Advances in Pure Mathematics》 2011年第3期67-72,共6页
We prove the non-existence of Hopf real hypersurfaces in complex two-plane Grassmannians whose Jacobi operators or the Jacobi corresponding to the directions in the distribution are of Codazzi type if they satisfy a f... We prove the non-existence of Hopf real hypersurfaces in complex two-plane Grassmannians whose Jacobi operators or the Jacobi corresponding to the directions in the distribution are of Codazzi type if they satisfy a further condition. We obtain that that they must be either of type (A) or of type (B) (see [2]), but no one of these satisfies our condition. As a consequence, we obtain the non-existence of Hopf real hypersurfaces in such ambient spaces whose Jacobi operators corresponding to -directions are parallel with the same further condition. 展开更多
关键词 Real HYPERSURFACES complex Two-plane GRASSMANNIANS JACOBI Operators Codazzi TYPE
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COMPLEX RAY EXPANSION OF PLANE WAVE
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作者 尧德中 阮颖铮 《Journal of Electronics(China)》 1994年第2期176-179,共4页
Based on the high frequency approximation theory, the complex ray expansion of plane wave is derived. The results obtained may be regarded as the basis of the numerical expansion of plane wave, which has been used suc... Based on the high frequency approximation theory, the complex ray expansion of plane wave is derived. The results obtained may be regarded as the basis of the numerical expansion of plane wave, which has been used successfully in some problems. 展开更多
关键词 WAVE PROPAGATION plane WAVE complex RAY
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Complex variable solution for boundary value problem with X-shaped cavity in plane elasticity and its application* 被引量:3
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作者 Hang ZHOU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第9期1329-1346,共18页
A new type of displacement pile, the X-section cast-in-place concrete (XCC) pile, has recently been developed in China. Extensive field tests and laboratory experi- ments are undertaken to evaluate its performance a... A new type of displacement pile, the X-section cast-in-place concrete (XCC) pile, has recently been developed in China. Extensive field tests and laboratory experi- ments are undertaken to evaluate its performance and quantify the non-uniform deforma- tion effect (NUDE) of the X-shaped cross section during installation. This paper develops a simplified theoretical model that attempts to capture the NUDE. Based on the theory of complex variable plane elasticity, closed-form solutions of the stress and displacement for the X-shaped cavity boundary value problem are given. Subsequently, the analytical solution is used to evaluate the NUDE, the concrete filling index (CFI), and the perimeter reduction coefficient of the XCC pile cross section. The computed results are compared with field test results, showing reasonable agreement. The present simplified theoretical model reveals the deformation mechanism of the X-shaped cavity and facilitates applica- tion of the newly developed XCC pile technique in geotechnical engineering. 展开更多
关键词 complex variable solution boundary value problem plane elasticity X-section cast-in-place concrete (XCC) pile deformation mechanism theoretical study
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PROBLEM OF THE PERIODIC WELDING OF ANISOTROPIC ELASTIC PLANE WITH DIFFERENT MATERIALS
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作者 黄民海 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第7期111-117,共7页
In this paper, the problem of the periodic welding of an anisotropic elastic half_plane and a strip with different materials is studied. By means of the complex variable method for plane elasticity and the theory of b... In this paper, the problem of the periodic welding of an anisotropic elastic half_plane and a strip with different materials is studied. By means of the complex variable method for plane elasticity and the theory of boundary value problems for analytic function, the stress distribution is given in closed forms. 展开更多
关键词 ANISOTROPIC plane elastic complex variable method WELDING boundary value problem
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Fundamental Solution for Welding Problem by Two Dissimilar Isotropic Semi-Planes
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作者 Yi Xuming Ye Biquan (Department of Mathematics,Wuhan University,Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期31-34,共4页
A fundamental solution was obtained for an infinite plane bonded by two dissimilar isotropic semi-planes by employing plane elastic complex variable method and theory of boundary value problems for analytic functions.... A fundamental solution was obtained for an infinite plane bonded by two dissimilar isotropic semi-planes by employing plane elastic complex variable method and theory of boundary value problems for analytic functions.Fundamental solution was prepared for solving these types of problems with boundary element method. 展开更多
关键词 complex variable method in plane elasticity boundary value problems for analytic functions fundamental solution BEM
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复杂结构楼板面内力学行为研究综述与展望
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作者 陶慕轩 蒋骋昊 潘文豪 《工程力学》 EI CSCD 北大核心 2024年第12期1-9,共9页
楼板是框架结构中受力机制最为复杂的构件之一。该文对复杂结构中楼板面内行为研究进行了综述,分别讨论了楼板面内基本受力性能和机理、楼板面内力学模型、楼板面内特性对结构整体性能的影响以及考虑楼板面内行为的设计方法,并在研究综... 楼板是框架结构中受力机制最为复杂的构件之一。该文对复杂结构中楼板面内行为研究进行了综述,分别讨论了楼板面内基本受力性能和机理、楼板面内力学模型、楼板面内特性对结构整体性能的影响以及考虑楼板面内行为的设计方法,并在研究综述的基础上,提出未来有待进一步研究的问题。综合考察关于楼板行为的一系列研究,总体上混凝土结构的研究成果比较丰富,组合结构的研究成果较为匮乏,而组合结构应用于复杂结构更具竞争力。因此,未来有待进一步针对组合结构体系,提出考虑面外组合作用的楼板面内非线性行为精细化高效数值模型,研究不同楼板面内力学模型对结构体系抗震性能的影响规律,建立楼板面内简化模型的误差定量评价方法,提出组合结构体系考虑楼板面内非线性行为的抗震设计方法。 展开更多
关键词 楼板 面内 复杂结构 组合结构 展望
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General solutions of plane problem for power function curved cracks
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作者 郭俊宏 袁泽帅 卢子兴 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第5期563-570,共8页
A new exact and universal conformal mapping is proposed. Using Muskhelishvili's complex potential method, the plane elasticity problem of power function curved cracks is investigated with an arbitrary power of a natu... A new exact and universal conformal mapping is proposed. Using Muskhelishvili's complex potential method, the plane elasticity problem of power function curved cracks is investigated with an arbitrary power of a natural number, and the general solutions of the stress intensity factors (SIFs) for mode I and mode II at the crack tip are obtained under the remotely uniform tensile loads. The present results can be reduced to the well-known solutions when the power of the function takes different natural numbers. Numerical examples are conducted to reveal the effects of the coefficient, the power, and the projected length along the x-axis of the power function curved crack on the SIFs for mode I and mode II. 展开更多
关键词 power function curved crack conformal mapping Muskhelishvili's complex potential method stress intensity factor (SIF) plane problem
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PROBLEMS OF COLLINEAR CRACKS BETWEEN BONDED DISSIMILAR MATERIALS UNDER ANTIPLANE CONCENTRATED FORCES
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作者 刘又文 蒋持平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第10期955-964,共10页
In this paper problems of collinear cracks between bonded dissimilar materials under antiplane concentrated forces are dealt with. General solutions of the problems are formulated by applying extended Schwarz principl... In this paper problems of collinear cracks between bonded dissimilar materials under antiplane concentrated forces are dealt with. General solutions of the problems are formulated by applying extended Schwarz principle integrated with the analysis of the singularity of complex stress functions. Closed-form solutions of several typical problems are obtained and the stress intensity factors are given. These solutions include a series of original results and some results of previous researches. It is found that under symmetrical loads the solutions for the dissimilar materials are the same as those for the homogeneous materia[7] 展开更多
关键词 anti-plane shear solid-solid interface CRACK complex functions singular solution stress intensity factor
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磁电弹性材料中圆弧形裂纹的反平面断裂问题 被引量:1
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作者 刘欣宇 刘官厅 《内蒙古师范大学学报(自然科学汉文版)》 CAS 2024年第1期17-26,共10页
利用广义复变函数理论和保角映射技术,研究磁电弹性复合材料中圆弧形裂纹在无穷远处受到沿磁电极化方向的磁/电载荷和反平面机械载荷的共同作用下的反平面问题,给出应力场及位移场的精确解析解,并获得在磁电全非渗透及全渗透边界条件下... 利用广义复变函数理论和保角映射技术,研究磁电弹性复合材料中圆弧形裂纹在无穷远处受到沿磁电极化方向的磁/电载荷和反平面机械载荷的共同作用下的反平面问题,给出应力场及位移场的精确解析解,并获得在磁电全非渗透及全渗透边界条件下圆弧裂纹尖端场强度因子和能量释放率的解析解。基于数值解进行数值分析,由数值结果表明:控制圆弧形裂纹半弦长与弓高比值的减少,可以提高材料的可靠性能;在两种边界条件下,机械载荷的不断增加最终会促进裂纹的扩展;在磁电全渗透边界条件下,裂纹扩展不受磁/电载荷的影响,但与材料常数和机械载荷的大小水平有关;在磁电全非渗透边界条件下,正(负)磁/电载荷的增加会阻碍裂纹扩展。 展开更多
关键词 磁电弹性复合材料 圆弧形裂纹 反平面问题 复变函数方法
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基于幅相复平面的空管雷达测高方法研究
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作者 田仕达 王诗惠 +1 位作者 包阳 方宇 《空天预警研究学报》 CSCD 2024年第4期289-293,共5页
针对两坐标体制的空管一次雷达对目标高度测量需求,提出了一种基于幅相复平面的空管一次雷达测高方法.利用高低双波束幅相差构建复平面,在复平面-仰角形成的复空间内形成拟合曲线,通过待测样本的高低波束幅相差值在三维拟合曲线进行插值... 针对两坐标体制的空管一次雷达对目标高度测量需求,提出了一种基于幅相复平面的空管一次雷达测高方法.利用高低双波束幅相差构建复平面,在复平面-仰角形成的复空间内形成拟合曲线,通过待测样本的高低波束幅相差值在三维拟合曲线进行插值,从而得到目标仰角,进而结合目标距离获得目标高度.实录数据统计分析表明,相比传统的比相测角方法,该方法在对低仰角和低信噪比目标的仰角测量精度上具有明显优势. 展开更多
关键词 空管一次雷达 雷达测高 幅相复平面
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基于近地层垂直速度能谱尺度特征确定复杂下垫面零平面位移
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作者 宋薇 彭珍 +1 位作者 邹钧 孙鉴泞 《气象科学》 2024年第1期157-165,共9页
本文利用位于南京市郊区的南京大学仙林校区SORPES观测站多层湍流观测数据分析了湍流谱特征,以白天不稳定条件下垂直速度能谱谱峰对应的长度尺度也就是离地高度为判据,探讨了运用该方法确定复杂下垫面零平面位移的可行性。统计分析表明... 本文利用位于南京市郊区的南京大学仙林校区SORPES观测站多层湍流观测数据分析了湍流谱特征,以白天不稳定条件下垂直速度能谱谱峰对应的长度尺度也就是离地高度为判据,探讨了运用该方法确定复杂下垫面零平面位移的可行性。统计分析表明,该方法确定的长度尺度呈现出较为一致的概率分布形状,概率最大的长度尺度对应于离地高度,在复杂下垫面情况下这个高度就是零平面位移高度到观测高度之间的距离,将观测点的离地高度减去这个距离就能得到零平面位移。本文同时运用不稳定条件下垂直速度方差在近地层中的相似关系来确定零平面位移,并与谱方法得到的结果进行对比。结果表明,谱方法和方差法得到的零平面位移非常接近。 展开更多
关键词 复杂下垫面 零平面位移 垂直速度能谱 垂直速度方差
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模糊复平面:点与线
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作者 王芳弟 刘自强 《兰州工业学院学报》 2024年第5期96-101,105,共7页
通过在模糊复平面中提出的模糊复点和模糊复线的概念,研究了模糊复平面的几何性质;定义了模糊复距离,证明了它是2个模糊复点之间的1个(弱)模糊复度量;讨论了模糊复线的基本性质;同时研究了模糊复线段、平行和相交的模糊复线,并给出了一... 通过在模糊复平面中提出的模糊复点和模糊复线的概念,研究了模糊复平面的几何性质;定义了模糊复距离,证明了它是2个模糊复点之间的1个(弱)模糊复度量;讨论了模糊复线的基本性质;同时研究了模糊复线段、平行和相交的模糊复线,并给出了一些实例说明了本文得到的结论。 展开更多
关键词 模糊复平面 模糊复点 模糊复线
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复平面区域面积的定积分与曲线积分表示
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作者 李静 王在华 《高等数学研究》 2024年第4期29-31,共3页
本文研究复平面内区域面积,从复平面内三角形面积出发,采用数学归纳法得到任意多边形面积计算公式,进而采用微元法得到平面内任意光滑简单闭曲线所围成区域面积的定积分与曲线积分计算公式.
关键词 复平面 面积 定积分 曲线积分
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BaTiO_3系PTCR材料电学性能的复阻抗解析 被引量:16
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作者 张中太 齐建全 +1 位作者 唐子龙 夏峰 《硅酸盐学报》 EI CAS CSCD 北大核心 1996年第1期100-104,共5页
采用复阻抗解析法研究了BaTiO_3系PTCR材料晶粒、晶界的电学性能。结果表明:使用欧姆接触电极的PTCR材料等效电路的复阻抗为 :晶粒电阻呈NTC特性,而晶界电阻在T<Tc时呈NTC特性,T>Tc时呈明显的PTC... 采用复阻抗解析法研究了BaTiO_3系PTCR材料晶粒、晶界的电学性能。结果表明:使用欧姆接触电极的PTCR材料等效电路的复阻抗为 :晶粒电阻呈NTC特性,而晶界电阻在T<Tc时呈NTC特性,T>Tc时呈明显的PTC特性;PTC效应是一种晶界效应。 展开更多
关键词 钛酸钡 晶粒 晶界 复阻抗 电学性 半导体材料
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8-羟基喹啉金属配合物在电致发光器件中的应用研究进展 被引量:21
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作者 周亚东 曾和平 +2 位作者 靖慧莲 袁国赞 欧阳新华 《有机化学》 SCIE CAS CSCD 北大核心 2006年第6期783-792,739,共10页
介绍了8-羟基喹啉金属配合物在有机电致发光器件中应用以及新研究进展.
关键词 8-羟基喹啉金属配合物 电致发光 平板显示器
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BaTiO_3基PTCR陶瓷的复阻抗谱研究 被引量:20
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作者 唐小锋 唐子龙 周志刚 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2000年第6期1037-1042,共6页
采用复阻抗方法,系统地研究了BaTiO3基PTCR陶瓷的电性能.通过Cole-Cole图,计算了样品的晶粒、晶界电阻值和弛豫时间常数,同时利用Heywang模型估算了势垒高度.Cole-Cole图分析表明,随着测试温... 采用复阻抗方法,系统地研究了BaTiO3基PTCR陶瓷的电性能.通过Cole-Cole图,计算了样品的晶粒、晶界电阻值和弛豫时间常数,同时利用Heywang模型估算了势垒高度.Cole-Cole图分析表明,随着测试温度的提高,Cole-Cole圆将从单半圆向双扭线过渡,表明在居里温度附近,由于热激活出现了不同的缺陷类型.实验结果表明了PTC效应是一种晶界效应,晶粒电阻随温度的变化呈NTC特性,而晶界电阻却呈明显的PTC特性.Heywang模型作为经典的理论模型,经过不断的完善,至今仍能对陶瓷材料PTC现象的宏观机制做出明确的解析。 展开更多
关键词 BaTiO3PTCR陶瓷 Cole-Cole图 复阻抗谱
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复杂环境下语音增强的复平面谱减法 被引量:6
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作者 王水平 唐振民 +1 位作者 陈北京 蒋晔 《南京理工大学学报》 EI CAS CSCD 北大核心 2013年第6期857-862,共6页
为了降低复杂环境中存在的各类噪声,消除噪声给语音识别及说话人识别等系统在军事自动指挥及控制领域等的应用中带来的影响,设计了一种新的谱减法。针对传统谱减法在语音增强过程中的原始语音和噪声信号相差为0的错误假设,提出一种基于... 为了降低复杂环境中存在的各类噪声,消除噪声给语音识别及说话人识别等系统在军事自动指挥及控制领域等的应用中带来的影响,设计了一种新的谱减法。针对传统谱减法在语音增强过程中的原始语音和噪声信号相差为0的错误假设,提出一种基于复平面的、考虑纯净语音与噪声及带噪语音之间相位差信息的改进谱减法,对增益函数进行修正。经过复杂的战场仿真环境测试表明,该方法性能较好,在低信噪比的环境下性能更优。对于输入信噪比为5 dB的带噪语音,经复平面谱减法去噪后,输出信噪比为12.21 dB,比传统谱减法提高了2.1 dB。 展开更多
关键词 复杂环境 语音增强 复平面 谱减法 增益函数
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