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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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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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磁电弹性材料中圆弧形裂纹的反平面断裂问题
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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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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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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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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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不同{021}/{110}晶面暴露比针铁矿对As(Ⅴ)吸附特性的研究
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作者 宋超凡 王晓睿 +2 位作者 杨昆仑 韩杰 缪恒锋 《环境科学研究》 CAS CSCD 北大核心 2023年第6期1166-1177,共12页
为探究针铁矿不同晶面对As(Ⅴ)的吸附能力,该研究制备两种具有不同比例{021}/{110}晶面的针铁矿,利用XRD、FTIR、N2吸附脱附等温线、SEM、TEM等技术表征材料的晶体结构、比表面积和表面形貌等情况.通过等温吸附和吸附动力学试验,研究不... 为探究针铁矿不同晶面对As(Ⅴ)的吸附能力,该研究制备两种具有不同比例{021}/{110}晶面的针铁矿,利用XRD、FTIR、N2吸附脱附等温线、SEM、TEM等技术表征材料的晶体结构、比表面积和表面形貌等情况.通过等温吸附和吸附动力学试验,研究不同初始As(Ⅴ)浓度、pH和竞争阴离子影响下,两种针铁矿吸附As(Ⅴ)的差异性.结果表明:①制备的针铁矿Goe-A和Goe-B均为高纯针铁矿,Goe-A和Goe-B的比表面积分别为92.76和46.78m^(2)/g.②As(Ⅴ)在针铁矿表面的吸附更符合Freundlich等温吸附模型和准二级动力学模型,表明吸附是以多层吸附和化学吸附为主;经比表面积归一化后,发现含有更高比例{021}/{110}晶面的Goe-B表面拥有更好的吸附性能,在pH=4时吸附量达到0.304mg/m^(2),是Goe-A的1.57倍.③pH会影响针铁矿的吸附,吸附量随着pH的增加而降低,而在碱性条件下Goe-B表现出更强的吸附能力.随As(Ⅴ)浓度的增加,大量配体吸附引起的点位竞争效应大于pH变化引起的静电力作用.④吸附前后XRD的变化表明,As(Ⅴ)主要吸附在针铁矿表面,而不是结合到针铁矿的晶体结构中;而FTIR和XPS分析发现,As(Ⅴ)通过与Fe—OH配体交换形成了新的络合物(Fe—O—As)吸附在针铁矿表面.研究显示,含有更高比例{021}/{110}晶面的针铁矿表现出更强的吸附性能,是修复环境砷污染的理想吸附剂. 展开更多
关键词 针铁矿 晶面 络合物 吸附 砷污染
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利用线性变换方法求解稳态受迫振动 被引量:1
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作者 宇文天浩 郝思洁 金文涛 《大学物理》 2023年第3期37-40,共4页
物体的受迫振动是大学物理力学部分基础且重要的内容.受迫振动在一定时间后会达到稳定状态,而该稳态下受迫振动方程的解是理解后续课程内容——共振现象的基础,具有重要的意义.本文利用线性变换方法详细求解受迫振动稳态解,相比于常规... 物体的受迫振动是大学物理力学部分基础且重要的内容.受迫振动在一定时间后会达到稳定状态,而该稳态下受迫振动方程的解是理解后续课程内容——共振现象的基础,具有重要的意义.本文利用线性变换方法详细求解受迫振动稳态解,相比于常规解析法,更加简洁和直观,且有助于学生深入理解线性代数在解决物理问题中的应用. 展开更多
关键词 受迫振动 稳态解 线性变换 矢量 复平面
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声波测井响应的二维谱与共振特征
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作者 沈建国 陈志东 +1 位作者 张强 沈永进 《石油物探》 CSCD 北大核心 2023年第5期972-989,共18页
在井内液体中激发瞬态振动后,该振动沿径向传播的分量被井壁无数次反射,在地层中激发出无数个纵波、横波,固井Ⅰ界面胶结差时还在套管固体中激发无数个套管模式波,其沿井轴方向传播时通过边界在井内液体中耦合出声波——耦合波。无数次... 在井内液体中激发瞬态振动后,该振动沿径向传播的分量被井壁无数次反射,在地层中激发出无数个纵波、横波,固井Ⅰ界面胶结差时还在套管固体中激发无数个套管模式波,其沿井轴方向传播时通过边界在井内液体中耦合出声波——耦合波。无数次反射波与耦合波叠加构成声波测井响应,该测井响应受频率和圆柱形状影响。瞬态振动的频率连续,其测井响应是频率f和井轴方向波数k的复变函数的双重积分,用双变量复变函数——二维谱描述。在f-k平面上,刚性壁圆柱形液体内能够传播的模式波其二维谱的极值呈双曲线分布,套管模式波和地层内的纵波的二维谱的极值呈斜直线分布。它们通过边界在井内液体中耦合,双曲线与斜直线相交,为满足边界条件,实现声波耦合,双变量复变函数在交点处没有极值,交点周围二维谱的极值分布改变:双曲线和斜直线均断开,沿斜直线分布的二维谱极值是纵波或套管波的频谱,靠近双曲线幅度大,离开则幅度快速减小,随频率变化构成频谱峰,在峰值附近频谱断开,频谱峰形状与套管和地层物理参数有关,决定首波波形形状,具有共振特征。在频率域用指数函数的频谱拟合断开的频谱峰形状得到首波的衰减系数,它是固井质量和地层物理衰减、声速的综合描述,可用于评价固井质量和非常规油气藏。改变套管井的套管厚度和半径发现,双曲线被各种方式截断,形成不同的耦合波,均具有共振特征。 展开更多
关键词 声波测井 频率 波数 复平面 双变量复变函数 波形形状 耦合
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复杂断块油田断层快速精准定位方法研究
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作者 李晓娜 杨滔 +1 位作者 张云 陈琦 《成都大学学报(自然科学版)》 2023年第3期330-336,共7页
复杂断块油田由于断层极为发育,切割关系复杂,给构造研究带来较大的困难,其储量规模受断层控制.在开发中要合理动用该类油藏,必须精细刻画断层的平面展布特征,为开发井的部署提供依据.根据井型不同,断层类型不同,斜井轨迹沿构造的高低,... 复杂断块油田由于断层极为发育,切割关系复杂,给构造研究带来较大的困难,其储量规模受断层控制.在开发中要合理动用该类油藏,必须精细刻画断层的平面展布特征,为开发井的部署提供依据.根据井型不同,断层类型不同,斜井轨迹沿构造的高低,通过公式法总结了12种模式来精准定位断层在平面上的位置.依靠研究成果,2018—2019年,在WJ油田部署了39口井,累计产油3.25×10~4 t,平均日产油3.5 t,取得了良好的开发效果,为该类油藏的动用提供了技术支撑. 展开更多
关键词 复杂断块 平面展布特征 12种模式
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复杂平面类多(高)层建筑室内消火栓系统竖向环状管网设计
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作者 刘江凌 《福建建筑》 2023年第10期111-114,共4页
水平环网系统难以满足建筑室内消火栓环状管网的性能化要求。但由于现行规范没有明文禁止,且竖向环网系统在平面复杂的多(高)层建筑中,设计难度较大,因此,水平环网系统在该类建筑设计中仍有应用,不利于系统供水的可靠性。基于某工程实例... 水平环网系统难以满足建筑室内消火栓环状管网的性能化要求。但由于现行规范没有明文禁止,且竖向环网系统在平面复杂的多(高)层建筑中,设计难度较大,因此,水平环网系统在该类建筑设计中仍有应用,不利于系统供水的可靠性。基于某工程实例,总结探讨了复杂平面类多(高)层建筑室内消火栓系统竖向环网的一般设计思路。提倡工程设计中应采用性能安全可靠的环状管网系统,并为该类建筑室内消火栓系统设计提供借鉴。 展开更多
关键词 复杂平面类 多(高)层建筑 室内消火栓系统 竖向环状管网
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一种基于BPCS的高容量可逆信息隐藏算法
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作者 马光亚 丁海洋 +1 位作者 张凡 秦定武 《北京印刷学院学报》 2023年第3期8-14,共7页
提出了一种基于位面复杂度的高容量可逆信息隐藏方法。首先通过计算低位平面中位平面复杂度分割(BPCS)复杂度筛选出最佳位平面,其次将筛选出的位平面进行实块和非实块划分,对块进行重构组成新的位平面,将辅助信息和秘密信息嵌入,最后通... 提出了一种基于位面复杂度的高容量可逆信息隐藏方法。首先通过计算低位平面中位平面复杂度分割(BPCS)复杂度筛选出最佳位平面,其次将筛选出的位平面进行实块和非实块划分,对块进行重构组成新的位平面,将辅助信息和秘密信息嵌入,最后通过块置乱、像素置乱和混沌加密对图像进行加密。基于这种算法,一定程度上优化了位平面嵌入选择,可以实现高容量的信息嵌入和图像恢复。 展开更多
关键词 位面复杂度分割 高容量 可逆信息隐藏 相关系数
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