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HAUSDORFF DIMENSION OF RECURRENCE SETS FOR MATRIX TRANSFORMATIONS OF TORI
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作者 Zhangnan HU Bing LI 《Acta Mathematica Scientia》 2025年第4期1659-1673,共15页
Let T:T^(d)→T^(d),defined by Tx=AX(mod 1),where A is a d×d integer matrix with eigenvalues 1<|λ_(1)|≤|λ_(2)|≤…≤|λ_(d)|,We investigate the Hausdorff dimension of the recurrence set R(ψ)={x∈T^(d):T^(n)... Let T:T^(d)→T^(d),defined by Tx=AX(mod 1),where A is a d×d integer matrix with eigenvalues 1<|λ_(1)|≤|λ_(2)|≤…≤|λ_(d)|,We investigate the Hausdorff dimension of the recurrence set R(ψ)={x∈T^(d):T^(n)x∈B(x,ψ(n))for infinitely many n}forα≥log|λ_(d)/λ_(1)|,whereψis a positive decreasing function defined onℕand its lower order at infinity isα=lim inf_(n→∞)-logψ(n)/n.In the case that A is diagonalizable overℚwith integral eigenvalues,we obtain the dimension formula. 展开更多
关键词 quantitative recurrence properties Hausdorff dimension matrix transformations
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Determination of Transmission Routing of OXC Nodes Based on AWG Multiplexer by Matrix Transformation 被引量:1
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作者 GUOAi-huang FUJun-mei 《Semiconductor Photonics and Technology》 CAS 2004年第1期1-4,7,共5页
The structures of the space switching and the wavelength switching optical cross connect (OXC) nodes which are based on the arrayed waveguide grating (AWG) multiplexer are analyzed.By the matrix transformation relatio... The structures of the space switching and the wavelength switching optical cross connect (OXC) nodes which are based on the arrayed waveguide grating (AWG) multiplexer are analyzed.By the matrix transformation relation between the input and output wavelengths of the AWG multiplexer, the wavelength transmission routings of the space switching and wavelength switching OXC nodes are determined. 展开更多
关键词 AWG multiplexer OXC nodes matrix transformation Wavelength transmission routing
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Matrix transformations of l^q(X) to l^p(Y )
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作者 GUO Hao LI Rong-lu WU Jun-de 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第1期78-86,共9页
Let X and Y be Banach spaces, 0 〈 q 〈 +∞, i ≤ p 〈 +∞. In this paper, we characterize matrix transformations of lq ( X ) to lp ( Y ).
关键词 matrix transformation sequence space demi-linear mapping.
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Research on the Applications of Probability Model and Matrix Transformation in Data Analysis and Management under the Environment of Information Time
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作者 Ying Cao 《International Journal of Technology Management》 2015年第7期152-154,共3页
In this paper, we research the probability theory and matrix transformation based technique to manage the data for processing and analysis. Clustering analysis research has a long history, over the decades, the import... In this paper, we research the probability theory and matrix transformation based technique to manage the data for processing and analysis. Clustering analysis research has a long history, over the decades, the importance and the cross characteristics with other research direction to get the affirmation of the people. The probability theory and linear algebra act as the powerful tool for analyzing and mining data. The experimental result illustrates the effectiveness. In the near future, we plan to conduct more theoretical analysis on the topic. 展开更多
关键词 Probability Model matrix transformation Data Analysis and Management.
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Real-Time Error Analysis of Multi-Channel Capacitive Voltage Transformer Using Co-Prediction Matrix
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作者 Jiusong Hu Ao Xiong +2 位作者 Yongqi Liu Guaxuan Xiao Yi Zhong 《Journal of Power and Energy Engineering》 2025年第1期1-17,共17页
Capacitive voltage transformers (CVTs) are essential in high-voltage systems. An accurate error assessment is crucial for precise energy metering. However, tracking real-time quantitative changes in capacitive voltage... Capacitive voltage transformers (CVTs) are essential in high-voltage systems. An accurate error assessment is crucial for precise energy metering. However, tracking real-time quantitative changes in capacitive voltage transformer errors, particularly minor variations in multi-channel setups, remains challenging. This paper proposes a method for online error tracking of multi-channel capacitive voltage transformers using a Co-Prediction Matrix. The approach leverages the strong correlation between in-phase channels, particularly the invariance of the signal proportions among them. By establishing a co-prediction matrix based on these proportional relationships, The influence of voltage changes on the primary measurements is mitigated. Analyzing the relationships between the co-prediction matrices over time allows for inferring true measurement errors. Experimental validation with real-world data confirms the effectiveness of the method, demonstrating its capability to continuously track capacitive voltage transformer measurement errors online with precision over extended durations. 展开更多
关键词 Capacitive Voltage transformers Co-Prediction matrix HIGH-VOLTAGE Measurement error
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The Dual Spaces of Sets of Difference Sequences of Order m and Matrix Transformations 被引量:4
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作者 Eberhard MALKOWSKY M.MURSALEEN Suthep SUANTAI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第3期521-532,共12页
Let p = (pk)k=0^∞ be a bounded sequence of positive reals, m C N and u be s sequence of nonzero terms. If x = (xk)k=0^∞ is any sequence of complex numbers we write Δ(m)x for the sequence of the m th order dif... Let p = (pk)k=0^∞ be a bounded sequence of positive reals, m C N and u be s sequence of nonzero terms. If x = (xk)k=0^∞ is any sequence of complex numbers we write Δ(m)x for the sequence of the m th order differences of x and Δu^(m)X = {x=(x)k=0^∞ uΔ(m)x ∈ X} for any set X of sequences. We determine the α-, β- and γ-duals of the sets Δμ^(m)X for X=co(p),c(p),l∞(p) and characterize some matrix transformations between these spaces Δ^(m)X. 展开更多
关键词 difference sequences dual spaces matrix transformations
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Error modeling of 3-RSR parallel robot based on D-H transformation matrix 被引量:3
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作者 李瑞琴 杨斌 《Journal of Measurement Science and Instrumentation》 CAS 2014年第3期53-59,2,共7页
By selecting any one limb of 3-RSR parallel robot as a research object, the paper establishes a position and orienta- tion relationship matrix between the moving platform and the base by means of Denavit-Hartenberg (... By selecting any one limb of 3-RSR parallel robot as a research object, the paper establishes a position and orienta- tion relationship matrix between the moving platform and the base by means of Denavit-Hartenberg (D-H) transformation matrix. The error mapping model is derived from original error to the error of the platform by using matrix differential method. This model contains all geometric original errors of the robot. The nonlinear implicit function relation between po- sition and orientation error of the platform and the original geometric errors is simplified as a linear explicit function rela- tion. The results provide a basis for further studying error analysis and error compensation. 展开更多
关键词 error modeling 3-RSR parallel robot Denavit-Hartenberg (D-H) transformation matrix
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基于Matrix Core的高性能多维FFT设计与优化 被引量:1
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作者 陆璐 祝松祥 +2 位作者 田卿燕 林海山 郭逸劼 《华南理工大学学报(自然科学版)》 北大核心 2025年第3期20-30,共11页
快速傅里叶变换(FFT)算法广泛应用于科学计算等领域。为了充分挖掘图形处理器(GPU)的计算能力并进一步提高FFT的计算效率,该文针对矩阵形式的Stockham FFT,提出了一种基于Matrix Core的高性能多维FFT计算方案。在计算优化方面,该方案利... 快速傅里叶变换(FFT)算法广泛应用于科学计算等领域。为了充分挖掘图形处理器(GPU)的计算能力并进一步提高FFT的计算效率,该文针对矩阵形式的Stockham FFT,提出了一种基于Matrix Core的高性能多维FFT计算方案。在计算优化方面,该方案利用Matrix Core加速FFT计算中的矩阵乘运算,同时通过编译器内部指令完成小粒度的矩阵乘加,使得Matrix Core支持更多尺寸的FFT计算。在内存优化方面,该方案使用2层迭代策略,以充分利用共享内存,减少与全局内存的数据交换;根据Matrix Core的矩阵数据在各个线程寄存器中的分布规律,直接在寄存器上完成FFT计算中大量存在的矩阵逐元素乘操作;通过对共享内存中的数据进行重排来缓解存储体冲突,并采用双缓冲策略缓解访存瓶颈。该文还提出了高效的矩阵转置策略,以加速多维FFT计算。在AMD MI250 GPU平台上将该方案与GPU上主流的高性能FFT计算库rocFFT和VkFFT进行了比较实验,结果表明:该方案在AMD MI250上的1维、2维和3维FFT平均计算效率均优于rocFFT和VkFFT,3维FFT的平均计算效率为rocFFT的1.5倍,为VkFFT的2.0倍,具有较好的性能提升;mcFFT的计算精度与rocFFT和VkFFT保持在相同水平。 展开更多
关键词 图形处理器 matrix Core 快速傅里叶变换 矩阵乘法
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CRACK IDENTIFICATION IN STEPPED CANTILEVER BEAM COMBINING WAVELET ANALYSIS WITH TRANSFORM MATRIX 被引量:1
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作者 Weiwei Zhang Zhihua Wang Hongwei Ma 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第4期360-368,共9页
This paper illustrates the crack identification method combining wavelet analysis with transform matrix. Firstly, the fundamental vibration mode was applied to wavelet analysis. The crack location was found by the pea... This paper illustrates the crack identification method combining wavelet analysis with transform matrix. Firstly, the fundamental vibration mode was applied to wavelet analysis. The crack location was found by the peaks of the wavelet coefficients. Secondly, based on the identified crack locations, a simple transform matrix method requiring only the first two tested natural frequencies was used to further identify the crack depth. The present method can be used for crack identification in a complex structure. Numerical results of crack identification of a stepped cantilever beam show that the suggested method is feasible. 展开更多
关键词 CRACK cantilever beam WAVELET transform matrix
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Inverse Transformation of Elliptical Relative State Transition Matrix 被引量:1
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作者 Jianfeng Yin Yinrui Rao Chao Han 《International Journal of Astronomy and Astrophysics》 2014年第3期419-428,共10页
A new set of relative orbit elements (ROEs) is used to derive a new elliptical formation flying model in previous work. In-plane and out-of-plane relative motions can be completely decoupled, which benefits elliptical... A new set of relative orbit elements (ROEs) is used to derive a new elliptical formation flying model in previous work. In-plane and out-of-plane relative motions can be completely decoupled, which benefits elliptical formation design. In order to study the elliptical control strategy and perturbation effects, it is necessary to derive the inverse transformation of the relative state transition matrix based on relative orbit elements. Poisson bracket theory is used to obtain the linear transformations between the two representations: the relative orbit elements and the geocentric orbital frame. In this paper, the details of these transformations are presented. 展开更多
关键词 RELATIVE ORBIT Elements ELLIPTICAL Formation FLYING RELATIVE State Transition matrix Inverse transformation POISSON BRACKET
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A Direct Transformation of a Matrix Spectrum
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作者 Albert Iskhakov Sergey Skovpen 《Advances in Linear Algebra & Matrix Theory》 2015年第3期109-128,共20页
A method is presented for calculating a matrix spectrum with a given set of eigenvalues. It can be used to build systems with different spectrums with the aim of choosing desired alternative. It enables a practical im... A method is presented for calculating a matrix spectrum with a given set of eigenvalues. It can be used to build systems with different spectrums with the aim of choosing desired alternative. It enables a practical implementation of control algorithms without resorting to transformation of variables. 展开更多
关键词 matrix SPECTRUM FROBENIUS matrix FROBENIUS transformATION Spectral EQUATION
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Transformation Matrix for Combined Loads Applied to Thin-Walled Structures
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作者 Abdelraouf M. Sami Alsheikh David William Alan Rees 《World Journal of Mechanics》 2022年第6期65-78,共14页
This paper transforms combined loads, applied at an arbitrary point of a thin-walled open section beam, to the shear centre of the cross-section of the beam. Therein, a generalized transformation matrix for loads with... This paper transforms combined loads, applied at an arbitrary point of a thin-walled open section beam, to the shear centre of the cross-section of the beam. Therein, a generalized transformation matrix for loads with respect to the shear centre is derived, this accounting for the bimoments that develop due to the way the combined loads are applied. This and the authors’ earlier paper (World Journal of Mechanics 2021, 11, 205-236) provide a full solution to the theory of thin-walled, open-section structures bearing combined loading. The earlier work identified arbitrary loading with the section’s area properties that are necessary to axial and shear stress calculations within the structure’s thin walls. In the previous paper attention is paid to the relevant axes of loading and to the transformations of loading required between axes for stress calculations arising from tension/compression, bending, torsion and shear. The derivation of the general transformation matrix applies to all types of loadings including, axial tensile and compression forces, transverse shear, longitudinal bending. One application, representing all these load cases, is given of a simple channel cantilever with an eccentrically located end load. 展开更多
关键词 Thin-Walled Structure Open Sections transformation matrix Load transformation Combined Load transformation Shear Centre WARPING BIMOMENT Sectorial Area Properties
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Orthogonalization of unified and extended Bézier basis and its transformation matrix
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作者 FANG Meie JI Zhongping WANG Guozhao 《Computer Aided Drafting,Design and Manufacturing》 2013年第1期41-46,共6页
UE-Brzier (unified and extended Brzier) basis is the unified form of Brzier-like bases, including polynomial Brzier basis, trigonometric polynomial and hyperbolic polynomial Brzier basis. Similar to the original Brz... UE-Brzier (unified and extended Brzier) basis is the unified form of Brzier-like bases, including polynomial Brzier basis, trigonometric polynomial and hyperbolic polynomial Brzier basis. Similar to the original Brzier-like bases, UE-Brzier basis func-tions are not orthogonal. In this paper, a group of orthogonal basis is constructed based on UE-Brzier basis. The transformation matrices between UE-Brzier basis and the proposed orthogonal basis are also solved. 展开更多
关键词 UE-B6zier basis ORTHOGONALIZATION legendre basis transformation matrix
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Effects of Heparin on Transforming Growth Factor-β_1 and Extracellular Matrix Components in the Glomeruli of Diabetic Rats
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作者 李元红 彭荔薰 +2 位作者 张木勋 欧阳金芝 张建华 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2003年第1期10-12,共3页
The effects of heparin on the expression of transforming growth factor-β 1 (TGF-β 1) and two extracellular matrix components laminin (LN) and fibronectin (FN) in diabetic rat glomeruli were investigated. Twent... The effects of heparin on the expression of transforming growth factor-β 1 (TGF-β 1) and two extracellular matrix components laminin (LN) and fibronectin (FN) in diabetic rat glomeruli were investigated. Twenty-six rats were randomly divided into control group (C, n=8), diabetic group (D, n=9), and diabetes+heparin group (DH, n=9). After 8-week therapy of heparin (200 U once daily by abdominal injection), TGF-β 1, LN and FN expression in glomeruli was detected by immunohistochemical method. The results showed that the expression levels of TGF-β 1, LN and FN were higher in group D than in group C. It was found that heparin could reduce 24-h urinary albumin excretion and inhibit overexpression of TGF-β 1, LN and FN in glomeruli of diabetic rats. It suggested that the inhibitory effect of heparin on diabetic glomerular sclerosis was at least partly related with the inhibition of TGF-β 1 expression. 展开更多
关键词 diabetic nephropathy HEPARIN transforming growth factor-β 1 extracellular matrix
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三维卷积与Transformer支持下联合空谱特征的高光谱影像分类 被引量:1
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作者 何光 吴田军 《计算机工程与应用》 北大核心 2025年第2期259-272,共14页
由于CNN对局部特征提取能力强,目前仍是高光谱影像处理和分析中的主流深度模型,但是CNN感受野有限,无法建立长距离依赖关系,学习全局语义信息受限。Transformer的自注意力机制可以对输入序列中的每个位置进行注意力计算,从而能有效获取... 由于CNN对局部特征提取能力强,目前仍是高光谱影像处理和分析中的主流深度模型,但是CNN感受野有限,无法建立长距离依赖关系,学习全局语义信息受限。Transformer的自注意力机制可以对输入序列中的每个位置进行注意力计算,从而能有效获取全局上下文信息。如何实现CNN和Transformer的技术耦合并充分利用空间信息和光谱信息进行高光谱遥感影像分类是一个重要的待研问题。鉴于此,提出一种新的基于三维卷积和Transformer的高光谱遥感影像分类方法,尝试联合空谱特征实现解译能力的提升。使用主成分分析方法对高光谱遥感影像沿垂直方向降维;用非负矩阵分解算法对降维后遥感影像沿水平方向进行空间特征提取,将两种工具处理后遥感影像进行拼接,以充分保留信息;再用三维卷积核对拼接后遥感影像进行空间特征和光谱特征的综合提取;用Transformer的注意力机制对提取空间信息和光谱信息的遥感影像序列建立长距离依赖关系并使用多层感知机完成分类任务。实验表明,所提方法在WHU-Hi龙口、汉川、洪湖以及雄安新区马蹄湾村数据集上均表现出比对比方法更优异的分类性能,表明该方法具有一定的泛化性和稳健性。 展开更多
关键词 非负矩阵分解 特征融合 三维卷积 空谱联合 transformER 高光谱遥感影像分类
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CHARACTERIZATIONS OF SOME MATRIX CLASSES OF QUASI-HOMOGENEOUS OPERATORS 被引量:1
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作者 陈爱红 李容录 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2285-2294,共10页
In this paper, we give a general characterization of a class of matrices of quasi-homogeneous operators between topological vector spaces.
关键词 matrix transformation quasi-homogeneous operator gliding hump property
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BANACH SPACES AND INEQUALITIES ASSOCIATED WITH NEW GENERALIZATION OF CESàRO MATRIX 被引量:1
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作者 Feyzi BASAR Hadi ROOPAEI 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1518-1536,共19页
Let the triangle matrix A^(ru)be a generalization of the Cesàro matrix and U∈{c_(0),c,l_(∞)}.In this study,we essentially deal with the space U(A^(ru))defined by the domain of A^(ru)in the space U and give the ... Let the triangle matrix A^(ru)be a generalization of the Cesàro matrix and U∈{c_(0),c,l_(∞)}.In this study,we essentially deal with the space U(A^(ru))defined by the domain of A^(ru)in the space U and give the bases,and determine the Kothe-Toeplitz,generalized K?theToeplitz and bounded-duals of the space U(A^(ru)).We characterize the classes(l_(∞)(A^(ru)):l_(∞)),(l_(∞)(A^(ru)):c),(c(A^(ru)):c),and(U:V(A^(ru)))of infinite matrices,where V denotes any given sequence space.Additionally,we also present a Steinhaus type theorem.As an another result of this study,we investigate the l_(p)-norm of the matrix A^(ru)and as a result obtaining a generalized version of Hardy's inequality,and some inclusion relations.Moreover,we compute the norm of well-known operators on the matrix domain l_(p)(A^(ru)). 展开更多
关键词 matrix domain normed sequence space duals and matrix transformations
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基于手机平台的Data Matrix 2维条码识别 被引量:4
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作者 刘宁钟 尤海英 孙涵 《中国图象图形学报》 CSCD 北大核心 2010年第2期287-293,共7页
传统的条码图像采集和识别是通过工业扫描枪。近年来,随着移动增值业务和3G技术的发展,2维条码在手机设备的应用中得到飞速发展。以Data Matrix为例,研究了基于嵌入式手机设备的2维条码识别技术。首先根据Data Matrix条码的特点,给出了... 传统的条码图像采集和识别是通过工业扫描枪。近年来,随着移动增值业务和3G技术的发展,2维条码在手机设备的应用中得到飞速发展。以Data Matrix为例,研究了基于嵌入式手机设备的2维条码识别技术。首先根据Data Matrix条码的特点,给出了一种基于链码跟踪和线段检测的快速Data Matrix检测算法。接着分析了条码信号经过点扩展函数卷积后的降质模型,并利用维纳滤波对条码信号进行反模糊滤波。最后,针对透视畸变的现象,设计了一种适合于嵌入式手机设备的快速反透视算法。实验结果表明,提出的识别算法具有优秀的性能,显著提高了条码的识别率,满足了实际使用的要求。 展开更多
关键词 2维条码 手机 DATA matrix反模糊 反透视变换
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考虑强噪声干扰的数字音频信号质量增强方法
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作者 张冰 《现代电子技术》 北大核心 2026年第1期73-76,共4页
针对数字音频信号中有效特征易被强噪声掩盖、时频域特性混淆,进而导致音频清晰度不足、可懂度大幅下降的问题,文中提出考虑强噪声干扰的数字音频信号质量增强方法。基于时段定位方法对强噪声实施预处理实现信号初步增强后,对目标时段... 针对数字音频信号中有效特征易被强噪声掩盖、时频域特性混淆,进而导致音频清晰度不足、可懂度大幅下降的问题,文中提出考虑强噪声干扰的数字音频信号质量增强方法。基于时段定位方法对强噪声实施预处理实现信号初步增强后,对目标时段数字音频信号进行短时傅里叶变换,映射至梅尔频率尺度,得到目标时段内含残留强噪声音频信号的精细特征。通过奇异值分解分离音频与噪声特征,经反对角线元素平均与特征逆转换,输出质量增强的数字音频信号。实验结果表明,所提方法可将SNR提升最高达7.2 dB,即便在-10 dB极端强噪声下,该方法仍展现出跨类型、跨强度的稳定增强优势,是一种具有普遍性、高效性的数字音频信息质量增强方法。 展开更多
关键词 强噪声干扰 数字音频信号 信号质量增强 短时傅里叶变换 梅尔频率倒谱 HANKEL矩阵
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DOMAIN OF THE DOUBLE SEQUENTIAL BAND MATRIX B(r,s) ON SOME MADDOX'S SPACES
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作者 Faruk OZGER Feyzi BASAR 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期394-408,共15页
The domain of generalized difference matrix B(r, s) in the classical spaces L∞, e, and co was recently studied by Kirisci and Basar in [16]. The main goal of this article is to introduce the paranormed sequence spa... The domain of generalized difference matrix B(r, s) in the classical spaces L∞, e, and co was recently studied by Kirisci and Basar in [16]. The main goal of this article is to introduce the paranormed sequence spaces L∞(B,p), c(B,p), and co(B,p), which are more general and comprehensive than the corresponding consequences of the matrix domain of B(r, s), as well as other studies in literature. Besides this, the alpha-, beta-, and gamma-duals of the spaces L∞ (B, p), c(B, p), and co (B, p) are computed and the bases of the spaces c(B, p) and co (B, p) are constructed. The final section of this article is devoted to the characterization of the classes (λ(B, p): μ) and (μ:λ(B, p)), where λ ∈ {c, co, L∞ } and μ is any given sequence space. Additionally, the characterization of some other classes which are related to the space of Mmost convergent sequences is obtained by means of a given lemma. 展开更多
关键词 matrix domain double sequential band matrices almost convergence para-normed spaces matrix transformations
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