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A color image encryption scheme based on a 2D coupled chaotic system and diagonal scrambling algorithm
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作者 苏静明 方士辉 +1 位作者 洪炎 温言 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期233-243,共11页
A novel color image encryption scheme is developed to enhance the security of encryption without increasing the complexity. Firstly, the plain color image is decomposed into three grayscale plain images, which are con... A novel color image encryption scheme is developed to enhance the security of encryption without increasing the complexity. Firstly, the plain color image is decomposed into three grayscale plain images, which are converted into the frequency domain coefficient matrices(FDCM) with discrete cosine transform(DCT) operation. After that, a twodimensional(2D) coupled chaotic system is developed and used to generate one group of embedded matrices and another group of encryption matrices, respectively. The embedded matrices are integrated with the FDCM to fulfill the frequency domain encryption, and then the inverse DCT processing is implemented to recover the spatial domain signal. Eventually,under the function of the encryption matrices and the proposed diagonal scrambling algorithm, the final color ciphertext is obtained. The experimental results show that the proposed method can not only ensure efficient encryption but also satisfy various sizes of image encryption. Besides, it has better performance than other similar techniques in statistical feature analysis, such as key space, key sensitivity, anti-differential attack, information entropy, noise attack, etc. 展开更多
关键词 color image encryption discrete cosine transform two-dimensional(2D)coupled chaotic system diagonal scrambling
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Criteria Condition for Generalized Diagonally Dominant Matrices 被引量:3
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作者 田素霞 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期102-106,共5页
In this paper, we provide some new necessary and sufficient conditions for generalized diagonally dominant matrices and also obtain some criteria for nongeneralized dominant matrices.
关键词 generalized diagonally dominant matrices Positive diagonal matrix criteria condition
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The Distribution of Eigenvance of Product Diagonal Dominance Matrix 被引量:1
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作者 杨益民 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期32-40,共9页
Let DD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(jj)|≥A_iA_j,i≠j,i,j∈N}.PD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(kk)|≥A_iA_jA_k,i≠j≠k,i,j,k∈N}. In this paper,we show DD_0(R)PD_0(R),and the conditions under which the nu... Let DD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(jj)|≥A_iA_j,i≠j,i,j∈N}.PD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(kk)|≥A_iA_jA_k,i≠j≠k,i,j,k∈N}. In this paper,we show DD_0(R)PD_0(R),and the conditions under which the numbers of eigen vance of A∈PD_0(R)\DD_0(R)are equal to the numbers of a_(ii),i∈N in positive and negative real part respectively.Some couter examples are given which present the condnions can not be omitted. 展开更多
关键词 MATRIX diagonal dominance EIGENVALUE DISTRIBUTION
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Missing Value Imputation for Radar-Derived Time-Series Tracks of Aerial Targets Based on Improved Self-Attention-Based Network
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作者 Zihao Song Yan Zhou +2 位作者 Wei Cheng Futai Liang Chenhao Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第3期3349-3376,共28页
The frequent missing values in radar-derived time-series tracks of aerial targets(RTT-AT)lead to significant challenges in subsequent data-driven tasks.However,the majority of imputation research focuses on random mis... The frequent missing values in radar-derived time-series tracks of aerial targets(RTT-AT)lead to significant challenges in subsequent data-driven tasks.However,the majority of imputation research focuses on random missing(RM)that differs significantly from common missing patterns of RTT-AT.The method for solving the RM may experience performance degradation or failure when applied to RTT-AT imputation.Conventional autoregressive deep learning methods are prone to error accumulation and long-term dependency loss.In this paper,a non-autoregressive imputation model that addresses the issue of missing value imputation for two common missing patterns in RTT-AT is proposed.Our model consists of two probabilistic sparse diagonal masking self-attention(PSDMSA)units and a weight fusion unit.It learns missing values by combining the representations outputted by the two units,aiming to minimize the difference between the missing values and their actual values.The PSDMSA units effectively capture temporal dependencies and attribute correlations between time steps,improving imputation quality.The weight fusion unit automatically updates the weights of the output representations from the two units to obtain a more accurate final representation.The experimental results indicate that,despite varying missing rates in the two missing patterns,our model consistently outperforms other methods in imputation performance and exhibits a low frequency of deviations in estimates for specific missing entries.Compared to the state-of-the-art autoregressive deep learning imputation model Bidirectional Recurrent Imputation for Time Series(BRITS),our proposed model reduces mean absolute error(MAE)by 31%~50%.Additionally,the model attains a training speed that is 4 to 8 times faster when compared to both BRITS and a standard Transformer model when trained on the same dataset.Finally,the findings from the ablation experiments demonstrate that the PSDMSA,the weight fusion unit,cascade network design,and imputation loss enhance imputation performance and confirm the efficacy of our design. 展开更多
关键词 Missing value imputation time-series tracks probabilistic sparsity diagonal masking self-attention weight fusion
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Zeno and the Wrong Understanding of Motion—A Philosophical-Mathematical Inquiry into the Concept of Finitude as a Peculiarity of Infinity
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作者 Andreas Herberg-Rothe 《Journal of Applied Mathematics and Physics》 2024年第3期912-929,共18页
In contrast to the solutions of applied mathematics to Zeno’s paradoxes, I focus on the concept of motion and show that, by distinguishing two different forms of motion, Zeno’s apparent paradoxes are not paradoxical... In contrast to the solutions of applied mathematics to Zeno’s paradoxes, I focus on the concept of motion and show that, by distinguishing two different forms of motion, Zeno’s apparent paradoxes are not paradoxical at all. Zeno’s paradoxes indirectly prove that distances are not composed of extensionless points and, in general, that a higher dimension cannot be completely composed of lower ones. Conversely, lower dimensions can be understood as special cases of higher dimensions. To illustrate this approach, I consider Cantor’s only apparent proof that the real numbers are uncountable. However, his widely accepted indirect proof has the disadvantage that it depends on whether there is another way to make the real numbers countable. Cantor rightly assumes that there can be no smallest number between 0 and 1, and therefore no beginning of counting. For this reason he arbitrarily lists the real numbers in order to show with his diagonal method that this list can never be complete. The situation is different if we start with the largest number between 0 and 1 (0.999…) and use the method of an inverted triangle, which can be understood as a special fractal form. Here we can construct a vertical and a horizontal stratification with which it is actually possible to construct all real numbers between 0 and 1 without exception. Each column is infinite, and each number in that column is the starting point of a new triangle, while each row is finite. Even in a simple sine curve, we experience finiteness with respect to the y-axis and infinity with respect to the x-axis. The first parts of this article show that Zeno’s assumptions contradict the concept of motion as such, so it is not surprising that this misconstruction leads to contradictions. In the last part, I discuss Cantor’s diagonal method and explain the method of an inverted triangle that is internally structured like a fractal by repeating this inverted triangle at each column. The consequence is that we encounter two very different methods of counting. Vertically it is continuous, horizontally it is discrete. While Frege, Tarski, Cantor, Gödel and the Vienna Circle tried to derive the higher dimension from the lower, a procedure that always leads to new contradictions and antinomies (Tarski, Russell), I take the opposite approach here, in which I derive the lower dimension from the higher. This perspective seems to fail because Tarski, Russell, Wittgenstein, and especially the Vienna Circle have shown that the completeness of the absolute itself is logically contradictory. For this reason, we agree with Hegel in assuming that we can never fully comprehend the Absolute, but only its particular manifestations—otherwise we would be putting ourselves in the place of the Absolute, or even God. Nevertheless, we can understand the Absolute in its particular expressions, as I will show with the modest example of the triangle proof of the combined horizontal and vertical countability of the real numbers, which I developed in rejection of Cantor’s diagonal proof. . 展开更多
关键词 Zeno False Assumptions about Motion Finitude INFINITY Cantor’s diagonal Method Inverted Triangle as a Different Method Vertical and Horizontal Dimensions Quantum Theory Relativity of Space and Time Depending on Velocity
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Diagonal街区的理念
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作者 熊燕 《山西建筑》 2004年第16期9-10,共2页
介绍了Diagonal街区的理论 ,阐述了Diagonal属于主要大街的一部分 ,指出在Diagonal街区的建筑不仅服务于一个目标 ,而且包含着多样的城市功能和办公空间及住宅 ,组成一个完整的街区。
关键词 diagonal街区 城市功能 办公空间 建筑景观
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NONNULL DISTRIBUTION OF THE LIKELIHOOD RATIO CRITERION FOR TESTING THE EQUALITY OF DIAGONAL BLOCKS WITH BLOCKWISE INDEPENDENCE 被引量:5
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作者 A. K. Gupta C. C. Chao(Bowling Green State University Bowling Green, OH 43403-0221 C. C. ChaoJacksonville State Univesity Jacksonville, AL 36265) 《Acta Mathematica Scientia》 SCIE CSCD 1994年第2期195-203,共9页
In this paper, the nonnull moments and the distributions of the likelihood ratio criterion for testing the equality of diagonal blocks with blockwise independence under certain alternatives have derived.
关键词 RATIO BLOCKWISE CRITERION diagonal DISTRIBUTION EQUALITY FOR INDEPENDENCE LIKELIHOOD NONNULL
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Diagonally loaded SMI algorithm based on inverse matrix recursion 被引量:7
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作者 Cao Jianshu Wang Xuegang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期160-163,共4页
The derivation of a diagonally loaded sample-matrix inversion (LSMI) algorithm on the busis of inverse matrix recursion (i.e.LSMI-IMR algorithm) is conducted by reconstructing the recursive formulation of covarian... The derivation of a diagonally loaded sample-matrix inversion (LSMI) algorithm on the busis of inverse matrix recursion (i.e.LSMI-IMR algorithm) is conducted by reconstructing the recursive formulation of covariance matrix. For the new algorithm, diagonal loading is by setting initial inverse matrix without any addition of computation. In addition, a corresponding improved recursive algorithm is presented, which is low computational complexity. This eliminates the complex multiplications of the scalar coefficient and updating matrix, resulting in significant computational savings. Simulations show that the LSMI-IMR algorithm is valid. 展开更多
关键词 Robust adaptive beamforming Space-time adaptive processing (STAP) diagonal loading Inverse matrix recursion
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GEAR CRACK EARLY DIAGNOSIS USING BISPECTRUM DIAGONAL SLICE 被引量:4
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作者 Li WeihuaZhang GuicaiShi TielinYang ShuziSchool of Mechanical Scienceand Engineering,Huazhong University of Scienceand Technology,Wuhan 430074, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第2期193-196,共4页
A study of bispectral analysis in gearbox condition monitoring is presented.The theory of bispectrum and quadratic phase coupling (QPC) is first introduced, and then equationsfor computing bispectrum slices are obtain... A study of bispectral analysis in gearbox condition monitoring is presented.The theory of bispectrum and quadratic phase coupling (QPC) is first introduced, and then equationsfor computing bispectrum slices are obtained. To meet the needs of online monitoring, a simplifiedmethod of computing bispectrum diagonal slice is adopted. Industrial gearbox vibration signalsmeasured from normal and tooth cracked conditions are analyzed using the above method. Experimentsresults indicate that bispectrum can effectively suppress the additive Gaussian noise andchracterize the QPC phenomenon. It is also shown that the 1-D bispectrum diagonal slice can capturethe non-Gaussian and nonlinear feature of gearbox vibration when crack occurred, hence, this methodcan be employed to gearbox real time monitoring and early diagnosis. 展开更多
关键词 condition monitoring gear crack early diagnosis quadratic phase coupling bispectrum diagonal slice
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Recent developments on applications of sequential loop closing and diagonal dominance control schemes to industrial multivariable system 被引量:4
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作者 A.H.Mazinan M.F.Kazemi 《Journal of Central South University》 SCIE EI CAS 2013年第12期3401-3420,共20页
With a focus on an industrial multivariable system, two subsystems including the flow and the level outputs are analysed and controlled, which have applicability in both real and academic environments. In such a case,... With a focus on an industrial multivariable system, two subsystems including the flow and the level outputs are analysed and controlled, which have applicability in both real and academic environments. In such a case, at first, each subsystem is distinctively represented by its model, since the outcomes point out that the chosen models have the same behavior as corresponding ones. Then, the industrial multivariable system and its presentation are achieved in line with the integration of these subsystems, since the interaction between them can not actually be ignored. To analyze the interaction presented, the Gershgorin bands need to be acquired, where the results are used to modify the system parameters to appropriate values. Subsequently, in the view of modeling results, the control concept in two different techniques including sequential loop closing control(SLCC) scheme and diagonal dominance control(DDC) schemes is proposed to implement on the system through the Profibus network, as long as the OPC(OLE for process control) server is utilized to communicate between the control schemes presented and the multivariable system. The real test scenarios are carried out and the corresponding outcomes in their present forms are acquired. In the same way, the proposed control schemes results are compared with each other, where the real consequences verify the validity of them in the field of the presented industrial multivariable system control. 展开更多
关键词 multivariable system diagonal dominance control sequential loop closing control Profibus network OPC server orifice relation interaction analysis Gershogerin bands non-minimum phase system
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Adaptive diagonal loaded minimum variance beamforming applied to medical ultrasound imaging 被引量:2
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作者 刘昊霖 张志宏 刘东权 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1826-1832,共7页
In order to enhance the robustness and contrast in the minimum variance(MV) beamformer, adaptive diagonal loading method was proposed. The conventional diagonal loading technique has already been used in the MV beamfo... In order to enhance the robustness and contrast in the minimum variance(MV) beamformer, adaptive diagonal loading method was proposed. The conventional diagonal loading technique has already been used in the MV beamformer, but has the drawback that its level is specified by predefined parameter and without consideration of input-data. To alleviate this problem, the level of diagonal loading was computed appropriately and automatically from the given data by shrinkage method in the proposed adaptive diagonal loaded beamformer. The performance of the proposed beamformer was tested on the simulated point target and cyst phantom was obtained using Field II. In the point target simulation, it is shown that the proposed method has higher lateral resolution than the conventional delay-and-sum beamformer and could be more robust in estimating the amplitude peak than the MV beamformer when acoustic velocity error exists. In the cyst phantom simulation, the proposed beamformer has shown that it achieves an improvement in contrast ratio and without distorting the edges of cyst. 展开更多
关键词 medical ultrasound imaging minimum variance BEAMFORMING diagonal loading delay-and-sum BEAMFORMING CONTRAST ROBUSTNESS
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Analysis of factors affecting diagonal tension and compression capacity of corner joints in furniture frames fabricated with dovetail key 被引量:2
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作者 Mosayeb Dalvand Ghanbar Ebrahimi +1 位作者 Akbar Rostampour Haftkhani Sadegh Maleki 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第1期155-168,共14页
This study was conducted to analyze the effect of joint type, and numbers and types of dovetail keys on diagonal tension and compression performance of corner joints in a furniture frame. Joint members were cut from w... This study was conducted to analyze the effect of joint type, and numbers and types of dovetail keys on diagonal tension and compression performance of corner joints in a furniture frame. Joint members were cut from white fir lumber. Butted and mitered joints were constructed with one and two dovetail key(s) with butterfly and H shapes. Joints were glued by polyvinyl acetate (PVAc) and cynoacrylate (CA). Compression capacity of joints was higher than diagonal tension. Mitered joints were stronger than butted ones. Butterfly dovetail keys were superior to H shape keys. Double keys performed better than single key. Experimental joints glued with PVAc were stronger than those glued with CA glue and control specimens. In terms of strength, butterfly dovetailed joints were comparable with doweled joints. 展开更多
关键词 diagonal tension diagonal compression dovetail key JOINTS LUMBER
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Ship motion extreme short time prediction of ship pitch based on diagonal recurrent neural network 被引量:3
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作者 SHEN Yan XIE Mei-ping 《Journal of Marine Science and Application》 2005年第2期56-60,共5页
A DRNN (diagonal recurrent neural network) and its RPE (recurrent prediction error) learning algorithm are proposed in this paper .Using of the simple structure of DRNN can reduce the capacity of calculation. The prin... A DRNN (diagonal recurrent neural network) and its RPE (recurrent prediction error) learning algorithm are proposed in this paper .Using of the simple structure of DRNN can reduce the capacity of calculation. The principle of RPE learning algorithm is to adjust weights along the direction of Gauss-Newton. Meanwhile, it is unnecessary to calculate the second local derivative and the inverse matrixes, whose unbiasedness is proved. With application to the extremely short time prediction of large ship pitch, satisfactory results are obtained. Prediction effect of this algorithm is compared with that of auto-regression and periodical diagram method, and comparison results show that the proposed algorithm is feasible. 展开更多
关键词 extreme short time prediction diagonal recursive neural network recurrent prediction error learning algorithm UNBIASEDNESS
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The theoretical study on diagonal wave interaction with perforated-wall breakwater with rock fill 被引量:2
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作者 LIU Hongjie LIU Yong LI Yucheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第6期103-110,共8页
The interaction of diagonal waves with perforated-wall breakwater partially filled with rock fill is studied using the linear potential theory. By means of the matched eigenfunction expansion method, an analytical met... The interaction of diagonal waves with perforated-wall breakwater partially filled with rock fill is studied using the linear potential theory. By means of the matched eigenfunction expansion method, an analytical method is presented to calculate the reflection coefficient and the wave force coefficient of the breakwater. The calculated results of the reflection coefficient for limiting cases are the same to the existing results. The main effect factors of the reflection coefficient and the wave force coefficient are analyzed by numerical examples. With the increasing of thickness of rock fill, the wave force coefficient on the perforated wall generally decreases, while the reflection coefficient increases. With the increasing of the incident angle of the wave, the reflection coefficient of the breakwater first decreases, reaches its minimum, and then increases monotonously. 展开更多
关键词 diagonal wave perforated wall rock fill reflection coefficient wave force
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Criteria Conditions for Generalized Diagonally Dominant Matrices 被引量:3
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作者 TIAN Su-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期63-67,共5页
In this paper, some new sufficient conditions for generalized dominant matrices are given, and some results in [1] are generalized and improved.
关键词 generalized diagonal dominant matrices α-diagonal dominant matrix criteria condition
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Tracking multiple targets in MIMO radar via adaptive asymmetric joint diagonalization with deflation 被引量:3
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作者 ZHANG Zhengyan ZHANG Jianyun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期731-741,共11页
In view of the low performance of adaptive asymmetric joint diagonalization(AAJD), especially its failure in tracking high maneuvering targets, an adaptive asymmetric joint diagonalization with deflation(AAJDd) al... In view of the low performance of adaptive asymmetric joint diagonalization(AAJD), especially its failure in tracking high maneuvering targets, an adaptive asymmetric joint diagonalization with deflation(AAJDd) algorithm is proposed. The AAJDd algorithm improves performance by estimating the direction of departure(DOD) and direction of arrival(DOA) directly, avoiding the reuse of the previous moment information in the AAJD algorithm.On this basis, the idea of sequential estimation of the principal component is introduced to turn the matrix operation into a constant operation, reducing the amount of computation and speeding up the convergence. Meanwhile, the eigenvalue is obtained, which can be used to estimate the number of targets. Then, the estimation of signal parameters via rotational invariance technique(ESPRIT) algorithm is improved to realize the automatic matching and association of DOD and DOA. The simulation results show that the AAJDd algorithm has higher tracking performance than the AAJD algorithm, especially when the high maneuvering target is tracked. The efficiency of the proposed method is verified. 展开更多
关键词 MIMO radar low complexity angles tracking adaptiveasymmetric joint diagonalization with deflation (AAJDd) high ma-neuvering target
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Online blind source separation based on joint diagonalization 被引量:2
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作者 Li Ronghua Zhou Guoxu Yang Zuyuan Xie Shengli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期229-233,共5页
A new algorithm is proposed for joint diagonalization. With a modified objective function, the new algorithm not only excludes trivial and unbalanced solutions successfully, but is also easily optimized. In addition, ... A new algorithm is proposed for joint diagonalization. With a modified objective function, the new algorithm not only excludes trivial and unbalanced solutions successfully, but is also easily optimized. In addition, with the new objective function, the proposed algorithm can work well in online blind source separation (BSS) for the first time, although this family of algorithms is always thought to be valid only in batch-mode BSS by far. Simulations show that it is a very competitive joint diagonalization algorithm. 展开更多
关键词 blind source separation joint diagonalization nonconvex optimization
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Diagonal Invariant Ideals of Topologically Graded C~*-algebras 被引量:2
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作者 XU Qing-xiang ZHANG Xiao-bo 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第4期338-341,共4页
We study diagonal invariant ideals of topologically graded C*-algebras over discrete groups. Since all Toeplitz algebras defined on discrete groups are topologically graded, the results in this paper have improved the... We study diagonal invariant ideals of topologically graded C*-algebras over discrete groups. Since all Toeplitz algebras defined on discrete groups are topologically graded, the results in this paper have improved the first author's previous works on this topic. 展开更多
关键词 Fell bundle topologically graded C*-algebra diagonal invariant ideal
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Hybrid reconstruction algorithm for computed tomography based on diagonal total variation 被引量:1
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作者 Lu-Zhen Deng Peng He +3 位作者 Shang-Hai Jiang Mian-Yi Chen Biao Wei Peng Feng 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第3期172-180,共9页
Inspired by total variation(TV), this paper represents a new iterative algorithm based on diagonal total variation(DTV) to address the computed tomography image reconstruction problem. To improve the quality of a reco... Inspired by total variation(TV), this paper represents a new iterative algorithm based on diagonal total variation(DTV) to address the computed tomography image reconstruction problem. To improve the quality of a reconstructed image, we used DTV to sparsely represent images when iterative convergence of the reconstructed algorithm with TV-constraint had no effect during the reconstruction process. To investigate our proposed algorithm, the numerical and experimental studies were performed, and rootmean-square error(RMSE) and structure similarity(SSIM)were used to evaluate the reconstructed image quality. The results demonstrated that the proposed method could effectively reduce noise, suppress artifacts, and reconstruct highquality image from incomplete projection data. 展开更多
关键词 COMPUTED TOMOGRAPHY (CT) Sparse-view reconstruction diagonal total variation (DTV) COMPRESSIVE sensing (CS)
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THE STRESS SUBSPACE OF HYBRID STRESS ELEMENT AND THE DIAGONALIZATION METHOD FOR FLEXIBILITY MATRIX H 被引量:2
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作者 张灿辉 冯伟 黄黔 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第11期1263-1273,共11页
The following is proved: 1) The linear independence of assumed stress modes is the necessary and sufficient condition for the nonsingular flexibility matrix; 2) The equivalent assumed stress modes lead to the identica... The following is proved: 1) The linear independence of assumed stress modes is the necessary and sufficient condition for the nonsingular flexibility matrix; 2) The equivalent assumed stress modes lead to the identical hybrid element. The Hilbert stress subspace of the assumed stress modes is established. So, it is easy to derive the equivalent orthogonal normal stress modes by Schmidt's method. Because of the resulting diagonal flexibility matrix, the identical hybrid element is free from the complex matrix inversion so that the hybrid efficiency, is improved greatly. The numerical examples show that the method is effective. 展开更多
关键词 hybrid stress finite element Hilbert stress subspace diagonalization method for flexibility matrix
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