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两种Gauss映射象体积的比较
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作者 周建伟 《苏州大学学报(自然科学版)》 CAS 1992年第3期245-248,共4页
本文给出比较两种Gauss映射象的体积的公式,并附带给出一关于对称矩阵行列式的不等式。
关键词 流形 体积 高斯映射象
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长为2~e的Z_4^-线性循环码的Gray映射象 被引量:1
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作者 王新华 江中豪 《北京交通大学学报》 CAS CSCD 北大核心 2006年第3期77-80,共4页
刻画了长为2e在Gray映射下的象是线性码的Z4-线性循环码;确定了长为2e在Gray映射下的象为循环码的Z4-线性循环码的结构,部分回答了Wolfmann提出的一个公开问题.
关键词 线性码 循环码 Gray映射象
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图象的部分分形映射压缩算法 被引量:5
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作者 王舟 余英林 《计算机研究与发展》 EI CSCD 北大核心 1998年第3期199-204,共6页
自Barnsley提出分形图象编码的概念,特别是Jacquin给出了第一个完全由计算机自动完成的图象编码算法以来,分形图象编码得到了越来越多的关注.一种新的趋势是将分形编码方法与其他方法相结合.结合方式之一是只对图象... 自Barnsley提出分形图象编码的概念,特别是Jacquin给出了第一个完全由计算机自动完成的图象编码算法以来,分形图象编码得到了越来越多的关注.一种新的趋势是将分形编码方法与其他方法相结合.结合方式之一是只对图象中的一部分进行分形编码而其他部分采用不同的编码方式.文中针对这一思想给出了部分分形映射,并对其在不同条件下的收敛性、拼贴定理等性质进行了讨论.对这一思想的可行性在理论上得到了一些有益的结论.还据此给出了通用的部分分形编码框架和一个新的具体实现算法.实验表明,在提高压缩比的同时,运算时间也缩短了. 展开更多
关键词 编码 分形映射 压缩算法 处理
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ImageReady3.0图象映射的创建与操作
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作者 曹 建 《电脑技术——Hello-IT》 2001年第7期49-50,共2页
经常上网的读者肯定遇到过这种情况,在某些网页中,一幅图象的不同位置存在有链接到不同地址的超链接。如果查看一下这类网页的HTML文件源代码,就会发现它实际上使用了图象映射(Image Map)技术。图象映射是利用图象上的一个或多个热点而... 经常上网的读者肯定遇到过这种情况,在某些网页中,一幅图象的不同位置存在有链接到不同地址的超链接。如果查看一下这类网页的HTML文件源代码,就会发现它实际上使用了图象映射(Image Map)技术。图象映射是利用图象上的一个或多个热点而实现的超链接。 展开更多
关键词 IMAGEREADY 3.0 映射 调板设置 处理软件
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用Mapedit来制作图象映射
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作者 周勇生 《电脑》 2000年第11期54-55,共2页
关键词 映射 Mapedit 编辑 计算机
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开、紧、连续映射与σ点有限基
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作者 刘罗飞 《湖南数学年刊》 1989年第Z1期120-123,共4页
文[1]证得拓扑空间 X 为可展空间的充要条件是 X 为度量空间的开、p 映射象、[3]又证明 X 具有点可数基当且仅当 X 为度量空间的开、连续、S映射象。本文的主要结果是:X 具有σ点有限基的充要条件是 X 为度量空间的开、紧、连续映射象。
关键词 度量空间 连续映射 映射象 充要条件 子空间 有限 当且仅当 维空间 离散空间 证明
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多值次伪压缩映象不动点和多值次增生映象零点的Ishikawa迭代逼近
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作者 高兴慧 崔艳兰 《延安大学学报(自然科学版)》 2003年第1期21-23,共3页
在一般的Banach空间中,研究了多值次伪压缩映象不动点和多值次增生映象零点的具有误差的Ishikawa迭代逼近问题,所得结果改进和推广了这一领域内一些相关的结果。
关键词 多值次伪压缩映射象 多值次增生映 误差 ISHIKAWA迭代序列
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基于图象的表面细节技术
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作者 王章野 陈正鸣 陆艳青 《计算机工程》 CAS CSCD 北大核心 2001年第6期14-16,共3页
主要讨论了几种基于图象的表面细节技术,这些技术可产生照片级的真实感绘制及惊人的视觉效果,并讨论它们在红外仿真成象中的应用。
关键词 表面细节 照片级真实 红外仿真 计算机图形学 真实图 纹理映射
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RMI原则在数学中的应用
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作者 单锋 苏伦华 +1 位作者 孙作安 程丛沈 《大学数学》 1995年第1期189-193,共5页
本文叙述了RMI原则的一些基本概念,例举了RMI原则在数学分析、线性代数、积分变换和概率论中的应用。
关键词 RMI原则 关系结构 可逆映射 反演 映射象
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Grbner基理论与拉丁方问题
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作者 陈入云 向淑晃 陈小松 《湖北民族学院学报(自然科学版)》 CAS 2008年第1期8-11,共4页
借助多项式映射原理和Grbner基理论,讨论和研究了n×n阶拉丁方问题,得到了判别方阵是n×n阶拉丁方的方法:存在n×n阶拉丁方当且仅当常数项的幂积与理想I的和是幂积h∈k[y1,y2,…,yn2]在一个映射下的象;若h是幂积,则变元y1... 借助多项式映射原理和Grbner基理论,讨论和研究了n×n阶拉丁方问题,得到了判别方阵是n×n阶拉丁方的方法:存在n×n阶拉丁方当且仅当常数项的幂积与理想I的和是幂积h∈k[y1,y2,…,yn2]在一个映射下的象;若h是幂积,则变元y1,y2,…,yn2的指数集合即为拉丁方的构成元素,其中I=<z1z2…z2nt-1>. 展开更多
关键词 多项式映射 映射 幂积 GROEBNER基 拉丁方
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M{2,3},M{2,4}和M{2,3,4}的有效刻画(英文)
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作者 征道生 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2016年第2期9-19,共11页
集合A到集合B上的一个一一映射f称为B的一个有效刻画。本文提出的选逆象指标法(SIIIM)给出集A_1={α:α=(I_s,η)~T∈C_s^(n×s)}到象集B_1={β:β=α(α~*α)^(-1)α~*,α∈A_1}的一个有效刻画公式,并证明了B_1是I{2,3}_s的稠密子... 集合A到集合B上的一个一一映射f称为B的一个有效刻画。本文提出的选逆象指标法(SIIIM)给出集A_1={α:α=(I_s,η)~T∈C_s^(n×s)}到象集B_1={β:β=α(α~*α)^(-1)α~*,α∈A_1}的一个有效刻画公式,并证明了B_1是I{2,3}_s的稠密子集,且I{2,3}_s的每个元素都与B_1的某个元素置换相似,利用上述结果,分别建立了I{2,3}和长方阵广义逆矩阵类M{2,3}.的有效刻画公式。再利用等式I{2,3}_s=I{2,4}_s=I{2,3,4}_s,进一步获得了M{2,4},M{2,3,4}的有效刻画公式.算法3.1可用于无重复地计算I{2,3}_s的任一个元素. 展开更多
关键词 广义逆的有效刻画 矩阵的奇异值分解 正交投影矩阵 映射公式的逆指数集 稠密子集
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正合列的一些推广 被引量:2
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作者 朱艳丽 《青海师范大学学报(自然科学版)》 2004年第4期8-12,共5页
本文主要把模论中的图追踪,五引理,马蹄引理推广到一般情形.
关键词 映射 映射和核 正合列
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Composite cone-beam filtered backprojection algorithm based on nutating line
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作者 WANG YU OU Zong-ying +1 位作者 SU Tie-ming WANG Feng 《Optoelectronics Letters》 EI 2006年第3期221-224,共4页
The FDK algorithm is the most popular cone beam algorithm in the medical and industrial imaging field. Due to data insufficiency acquired from a circular trajectory, the images reconstructed by the FDK algorithm suffe... The FDK algorithm is the most popular cone beam algorithm in the medical and industrial imaging field. Due to data insufficiency acquired from a circular trajectory, the images reconstructed by the FDK algorithm suffer from the intensity droping with increasing cone angle. To overcome the drawback,a modified FDK algorithm is presented by convert the 1D ramp filtering direction from along the horizontal lines to along the nutating lines based on the result of Turbell. Unlike Turbell's method,there is no need for our algorithm to rebin the cone-beam data into 3D parallel-beam data before reconstructing. Moreover pre-weighting of the projection data is corrected by compensating for the cone angle effect. In addition,another correction term derived from the result of Hu is also induced into our algorithm. The simulation experiments demonstrate that the final algorithm can SUDDress the intensity droD associated with the FDK algorithm. 展开更多
关键词 复合材料 FDK算法 映射 重建
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Mapping of Freshwater Lake Wetlands Using Object-Relations and Rule-based Inference 被引量:1
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作者 RUAN Renzong Susan USTIN 《Chinese Geographical Science》 SCIE CSCD 2012年第4期462-471,共10页
Inland freshwater lake wetlands play an important role in regional ecological balance. Hongze Lake is the fourth biggest freshwater lake in China. In the past three decades, there has been significant loss of freshwat... Inland freshwater lake wetlands play an important role in regional ecological balance. Hongze Lake is the fourth biggest freshwater lake in China. In the past three decades, there has been significant loss of freshwater wet- lands within the lake and at the mouths of neighboring rivers, due to disturbance, primarily from human activities. The main purpose of this paper was to explore a practical technology for differentiating wetlands effectively from upland types in close proximity to them. In the paper, an integrated method, which combined per-pixel and per-field classifi- cation, was used for mapping wetlands of Hongze Lake and their neighboring upland types. Firstly, Landsat ETM+ imagery was segmented and classified by using spectral and textural features. Secondly, ETM+ spectral bands, textural features derived from ETM+ Pan imagery, relative relations between neighboring classes, shape fea^xes, and elevation were used in a decision tree classification. Thirdly, per-pixel classification results from the decision tree classifier were improved by using classification results from object-oriented classification as a context. The results show that the technology has not only overcome the salt-and-pepper effect commonly observed in the past studies, but also has im- proved the accuracy of identification by nearly 5%. 展开更多
关键词 rule-based inferring object-based classification freshwater lake wetland relation feature Hongze Lake
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Some Surjectivity Theorems for Maximal Monotone Operators and Its Application
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作者 WU Yue-xiang WANG La-di 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期615-620,共6页
The main purpose of this paper is to study the surjectivity theorems for maximal monotone mapping in reflexive Banach spaces by using fixed point theory. We prove some new surjectivity theorems under some conditions a... The main purpose of this paper is to study the surjectivity theorems for maximal monotone mapping in reflexive Banach spaces by using fixed point theory. We prove some new surjectivity theorems under some conditions and give its application in differential equation. 展开更多
关键词 maximal monotone mapping surjectivity theorems nonlinear equation
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AN IMPROVED RADIAL BASIS FUNCTION BASED METHOD FOR IMAGE WARPING
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作者 NieXuan ZhaoRongchun +1 位作者 ZhangCheng ZhangXiaoyan 《Journal of Electronics(China)》 2005年第4期422-426,共5页
A new image warping method is proposed in this letter, which can warp a given image by some manual defined features. Based on the radial basis interpolation function algorithm, the proposed method can transform the or... A new image warping method is proposed in this letter, which can warp a given image by some manual defined features. Based on the radial basis interpolation function algorithm, the proposed method can transform the original optimized problem into nonsingular linear problem by adding one-order term and affine differentiable condition. This linear system can get the steady unique solution by choosing suitable kernel function. Furthermore, the proposed method demonstrates how to set up the radial basis function in the target image so as to achieve supports to adopt the backward re-sampling technology accordingly which could gain the very slippery warping image. Theexperimental result shows that the proposed method can implement smooth and gradual image warping with multi-anchor points' accurate interpolation. 展开更多
关键词 Image warping Radial basis function Pixel mapping Affine map
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ImageReady 3.0的系统配置
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作者 曹建 《电脑技术——Hello-IT》 2001年第11期43-45,共3页
为了在图象处理中获得比较好的视觉效果和精确处理的参考标准,无论是Photoshop 6.0还是ImageReady 3.0都允许用户设置它的系统环境。本文主要讲解ImageReady 3.0所独有的针对Web图象处理的系统设置项目及设置操作方法。
关键词 IMAGEREADY3.0 处理软件 系统配置 映射
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Frontpage2002的两个另类功能
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作者 魏文 《电脑知识与技术(过刊)》 2003年第16期87-89,共3页
关键词 FRONTPAGE2002 网页制作 映射编辑 网页属性 个人主页
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Mapped Finite Element Discrete Variable Representation
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作者 De-quan Yu Shu-lin Cong +1 位作者 Dong H. Zhang Zhi-gang Sun 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第6期755-764,I0005,共11页
Efficient numerical solver for the SchrSdinger equation is very important in physics and chemistry. The finite element discrete variable representation (FE-DVR) was first proposed by Rescigno and Mc-Curdy [Phys. Rev... Efficient numerical solver for the SchrSdinger equation is very important in physics and chemistry. The finite element discrete variable representation (FE-DVR) was first proposed by Rescigno and Mc-Curdy [Phys. Rev. A 62, 032706 (2000)] for solving quantum-mechanical scattering problems. In this work, an FE-DVR method in a mapped coordinate was proposed to improve the efficiency of the original FE-DVR method. For numerical demonstration, the proposed approach is applied for solving the electronic eigenfunctions and eigenvalues of the hydrogen atom and vibrational states of the electronic state 3E+ of the Cs2 molecule which has long-range interaction potential. The numerical results indicate that the numerical efficiency of the original FE-DVR has been improved much using our proposed mapped coordinate scheme. 展开更多
关键词 Discrete variable representation Mapped Fourier method Ultra-cold atomic photoassociation Schrodinger equation solver Singularity of Coulomb potential
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Bloch Constant of Holomorphic Mappings on the Unit Ball of C^n 被引量:7
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作者 Jianfei WANG Taishun LIU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2007年第6期677-684,共8页
In this paper, the authors establish distortion theorems for various subfamilies Hk(B) of holomorphic mappings defined in the unit ball in C^n with critical points, where k is any positive integer. In particular, th... In this paper, the authors establish distortion theorems for various subfamilies Hk(B) of holomorphic mappings defined in the unit ball in C^n with critical points, where k is any positive integer. In particular, the distortion theorem for locally biholomorphic mappings is obtained when k tends to -∞. These distortion theorems give lower bounds on [det f′(z)[ and Re det f′(z). As an application of these distortion theorems, the authors give lower and upper bounds of Bloch constants for the subfamilies βk(M) of holomorphic mappings. Moreover, these distortion theorems are sharp. When B is the unit disk in C, these theorems reduce to the results of Liu and Minda. A new distortion result of Re det f′(z) for locally biholomorphic mappings is also obtained. 展开更多
关键词 Bloch constant Holomorphic mappings Locally biholomorphic mappings Critical points
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