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利用快速W变换计算离散sine变换及离散cosine变换的新算法 被引量:7
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作者 朱跃生 马维祯 《数据采集与处理》 CSCD 1990年第3期9-12,共4页
本文导出了DWT-Ⅲ与DST-Ⅳ,DCT-Ⅳ的关系式,构造了用FWT计算DST-Ⅳ,DCT-Ⅳ的新算法。新算法结构规则,计算效率高。
关键词 数字信号处理 W变换 sine变换 离散
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利用快速W变换计算偶离散cosine变换-Ⅳ的新算法 被引量:3
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作者 吴一全 王厚枢 《数据采集与处理》 CSCD 1992年第1期10-18,共9页
偶离散cosine变换-Ⅳ(EDCT-Ⅳ)的快速算法是计算各类EDCT的关键。本文系统地导出了常用的四种类型离散W变换(DWT-j,j=Ⅰ,Ⅱ,Ⅲ,Ⅳ)与EDCT—Ⅳ的关系式,从而构造了用快速W变换(FWT-j)计算EDCT-Ⅳ的四种新算法。文中给出了四种算法的运算... 偶离散cosine变换-Ⅳ(EDCT-Ⅳ)的快速算法是计算各类EDCT的关键。本文系统地导出了常用的四种类型离散W变换(DWT-j,j=Ⅰ,Ⅱ,Ⅲ,Ⅳ)与EDCT—Ⅳ的关系式,从而构造了用快速W变换(FWT-j)计算EDCT-Ⅳ的四种新算法。文中给出了四种算法的运算量,并与EDCT-Ⅳ的其它快速算法进行了比较。 展开更多
关键词 W变换 cosine变换 算法
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基于分数阶Cosine和Sine变换说话人证实特征的提取
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作者 王金芳 杨宝俊 李月 《石家庄铁道学院学报》 2008年第2期66-69,共4页
提出了基于分数阶Cosine变换和分数阶Sine变换用于说话人证实的新颖特征,即广义Bark平均能量差和主、从分数阶域间广义Bark平均能量差。为考核这些特征的实用性能,完成了一系列说话人证实实验。虽然上述特征的单一应用并未体现出极佳的... 提出了基于分数阶Cosine变换和分数阶Sine变换用于说话人证实的新颖特征,即广义Bark平均能量差和主、从分数阶域间广义Bark平均能量差。为考核这些特征的实用性能,完成了一系列说话人证实实验。虽然上述特征的单一应用并未体现出极佳的准确率,但它们经过合理组合后的性能同原单一特征相比更能良好地描述说话人声音个性。 展开更多
关键词 说话人证实 分数阶cosine变换 分数阶sine变换 特征提取
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图象编码技术与COSINE变换
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作者 熊庭刚 《舰船指挥控制系统》 1995年第3期45-50,共6页
电视,电影和照片都是常见的模拟图象的例子,正如所有模拟信号一样,模拟图象在处理(比如在一部电影胶片或一盒录像带复制期间或在电视信号的发射期间)时,其质量可能降低。而数字图象的处理能够防止图象质量的下降,不仅如此,还给计算机处... 电视,电影和照片都是常见的模拟图象的例子,正如所有模拟信号一样,模拟图象在处理(比如在一部电影胶片或一盒录像带复制期间或在电视信号的发射期间)时,其质量可能降低。而数字图象的处理能够防止图象质量的下降,不仅如此,还给计算机处理和修改图象打开了大门。 例如,用传统的彩色照相术,为了处理、放大和复印一个图象,需要复杂的化学、光学和印刷处理。存贮或分发传统的照片也是件麻烦的事。相比之下,使用一个电子摄像机所获得的照片能够存贮在各种介质上(如EEPROM、磁盘或光盘等)。 展开更多
关键词 编码 cosine变换 图象处理 通信
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求广义KP方程精确行波解的sine-cosine方法和推广的tanh方法 被引量:3
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作者 韦敏志 唐生强 《桂林电子科技大学学报》 2012年第1期65-68,共4页
运用sine-cosine方法和推广的tanh方法求解广义KP方程,以获得其类孤立波解和紧孤子解,这2类精确解的主要特点是具有超强的稳定性,从而对非线性偏微分方程的研究具有重要的意义,sine-cosine方法和推广的tanh方法为众多的非线性偏微分方... 运用sine-cosine方法和推广的tanh方法求解广义KP方程,以获得其类孤立波解和紧孤子解,这2类精确解的主要特点是具有超强的稳定性,从而对非线性偏微分方程的研究具有重要的意义,sine-cosine方法和推广的tanh方法为众多的非线性偏微分方程的求解提供了有效的数学工具。 展开更多
关键词 广义KP方程 类孤立波解 紧孤子解 sine-cosine方法 推广的tanh方法
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一种基于Logistic-Sine-Cosine映射的彩色图像加密算法 被引量:9
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作者 张赛男 李千目 《计算机科学》 CSCD 北大核心 2022年第1期353-358,共6页
科技的飞速发展为拍摄和分享图像带来了便利,但随着图像数据的急剧增多,泄露和篡改等安全问题也频频发生,图像加密技术的应用迫在眉睫,尤其是彩色图像的加密急需改进与发展。传统的加密技术主要是针对数据流加密,其效率低、计算量大,存... 科技的飞速发展为拍摄和分享图像带来了便利,但随着图像数据的急剧增多,泄露和篡改等安全问题也频频发生,图像加密技术的应用迫在眉睫,尤其是彩色图像的加密急需改进与发展。传统的加密技术主要是针对数据流加密,其效率低、计算量大,存在一定的局限性。基于变换域加密将图像从空域变换到频域进行加密再变换到空域,属于一种有损加密。基于混沌的加密,密钥空间大,实现简单,加密速度快,一般需要采用多个混沌系统来增强加密的安全性。为此,文中设计了一种针对彩色图像RGB三通道的简单安全的空域加密算法,先由Logistic-Sine-Cosine映射生成较为安全的混沌序列,接着利用混沌序列设计4轮置乱和扩散像素,最后,在一系列安全性分析实验中验证了基于Logistic-Sine-Cosine映射的彩色图像加密算法的安全性和有效性。 展开更多
关键词 RGB彩色图像 Logistic-sine-cosine映射 行列通道置乱 三通道像素 图像加密
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基于Logistic-Sine-Cosine映射的图像加密算法 被引量:3
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作者 黄佳鑫 赵凯悦 +1 位作者 李佳文 李珊珊 《科学技术与工程》 北大核心 2023年第27期11713-11721,共9页
为了提高数字图像加密的速度和算法的安全性,提出了基于Fridrich框架的加密算法。通过Fisher-Yates变换置乱原始图像打破像素间的强相关性,再利用滤波器在RGB平面上进行滤波得到密文。Logistic-Sine-Cosine复合混沌系统具有良好的混沌特... 为了提高数字图像加密的速度和算法的安全性,提出了基于Fridrich框架的加密算法。通过Fisher-Yates变换置乱原始图像打破像素间的强相关性,再利用滤波器在RGB平面上进行滤波得到密文。Logistic-Sine-Cosine复合混沌系统具有良好的混沌特性,且时间复杂度低。密钥由输入参数和明文的SHA-512值共同决定,对明文高度敏感。二维滤波器扩散效果良好,其滤波器模板由明文和密钥决定并引入了伪随机像素值,在提升扩散效果的同时增强了系统抗差分攻击的能力。仿真结果表明,密文图像像素分布近似均匀、像素关联性弱、密钥空间足够大、密钥敏感性高,能够有效抵抗暴力、裁剪、差分等常见攻击,具有较高的安全性,且算法时间复杂度较低。 展开更多
关键词 图像加密 Logistic-sine-cosine映射 Fisher-Yates置乱 滤波器扩散 SHA-512(secure hash algorithm-512)
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Sine Cosine Optimization with Deep Learning-Based Applied Linguistics for Sentiment Analysis on COVID-19 Tweets 被引量:1
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作者 Abdelwahed Motwakel Hala J.Alshahrani +5 位作者 Abdulkhaleq Q.A.Hassan Khaled Tarmissi Amal S.Mehanna Ishfaq Yaseen Amgad Atta Abdelmageed Mohammad Mahzari 《Computers, Materials & Continua》 SCIE EI 2023年第6期4767-4783,共17页
Applied linguistics is an interdisciplinary domain which identifies,investigates,and offers solutions to language-related real-life problems.The new coronavirus disease,otherwise known as Coronavirus disease(COVID-19)... Applied linguistics is an interdisciplinary domain which identifies,investigates,and offers solutions to language-related real-life problems.The new coronavirus disease,otherwise known as Coronavirus disease(COVID-19),has severely affected the everyday life of people all over the world.Specifically,since there is insufficient access to vaccines and no straight or reliable treatment for coronavirus infection,the country has initiated the appropriate preventive measures(like lockdown,physical separation,and masking)for combating this extremely transmittable disease.So,individuals spent more time on online social media platforms(i.e.,Twitter,Facebook,Instagram,LinkedIn,and Reddit)and expressed their thoughts and feelings about coronavirus infection.Twitter has become one of the popular social media platforms and allows anyone to post tweets.This study proposes a sine cosine optimization with bidirectional gated recurrent unit-based senti-ment analysis(SCOBGRU-SA)on COVID-19 tweets.The SCOBGRU-SA technique aimed to detect and classify the various sentiments in Twitter data during the COVID-19 pandemic.The SCOBGRU-SA technique follows data pre-processing and the Fast-Text word embedding process to accomplish this.Moreover,the BGRU model is utilized to recognise and classify sen-timents present in the tweets.Furthermore,the SCO algorithm is exploited for tuning the BGRU method’s hyperparameter,which helps attain improved classification performance.The experimental validation of the SCOBGRU-SA technique takes place using a benchmark dataset,and the results signify its promising performance compared to other DL models. 展开更多
关键词 Applied linguistics deep learning sentiment analysis COVID-19 pandemic sine cosine optimization TWITTER
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Logarithmic Sine and Cosine Transforms and Their Applications to Boundary-Value Problems Connected with Sectionally-Harmonic Functions
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作者 Mithat Idemen 《Applied Mathematics》 2013年第2期378-386,共9页
Let stand for the polar coordinates in R2, ?be a given constant while satisfies the Laplace equation in the wedge-shaped domain or . Here αj(j = 1,2,...,n + 1) denote certain angles such that αj αj(j = 1,2,...,n + ... Let stand for the polar coordinates in R2, ?be a given constant while satisfies the Laplace equation in the wedge-shaped domain or . Here αj(j = 1,2,...,n + 1) denote certain angles such that αj αj(j = 1,2,...,n + 1). It is known that if r = a satisfies homogeneous boundary conditions on all boundary lines ?in addition to non-homogeneous ones on the circular boundary , then an explicit expression of in terms of eigen-functions can be found through the classical method of separation of variables. But when the boundary?condition given on the circular boundary r = a is homogeneous, it is not possible to define a discrete set of eigen-functions. In this paper one shows that if the homogeneous condition in question is of the Dirichlet (or Neumann) type, then the logarithmic sine transform (or logarithmic cosine transform) defined by (or ) may be effective in solving the problem. The inverses of these transformations are expressed through the same kernels on or . Some properties of these transforms are also given in four theorems. An illustrative example, connected with the heat transfer in a two-part wedge domain, shows their effectiveness in getting exact solution. In the example in question the lateral boundaries are assumed to be non-conducting, which are expressed through Neumann type boundary conditions. The application of the method gives also the necessary condition for the solvability of the problem (the already known existence condition!). This kind of problems arise in various domain of applications such as electrostatics, magneto-statics, hydrostatics, heat transfer, mass transfer, acoustics, elasticity, etc. 展开更多
关键词 INTEGRAL Transforms Harmonic Functions WEDGE PROBLEMS Boundary-Value PROBLEMS Logarithmic sine TRANSFORM Logarithmic cosine TRANSFORM
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A Double Adaptive Random Spare Reinforced Sine Cosine Algorithm
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作者 Abdelazim G.Hussien Guoxi Liang +1 位作者 Huiling Chen Haiping Lin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2267-2289,共23页
Many complex optimization problems in the real world can easily fall into local optimality and fail to find the optimal solution,so more new techniques and methods are needed to solve such challenges.Metaheuristic alg... Many complex optimization problems in the real world can easily fall into local optimality and fail to find the optimal solution,so more new techniques and methods are needed to solve such challenges.Metaheuristic algorithms have received a lot of attention in recent years because of their efficient performance and simple structure.Sine Cosine Algorithm(SCA)is a recent Metaheuristic algorithm that is based on two trigonometric functions Sine&Cosine.However,like all other metaheuristic algorithms,SCA has a slow convergence and may fail in sub-optimal regions.In this study,an enhanced version of SCA named RDSCA is suggested that depends on two techniques:random spare/replacement and double adaptive weight.The first technique is employed in SCA to speed the convergence whereas the second method is used to enhance exploratory searching capabilities.To evaluate RDSCA,30 functions from CEC 2017 and 4 real-world engineering problems are used.Moreover,a nonparametric test called Wilcoxon signed-rank is carried out at 5%level to evaluate the significance of the obtained results between RDSCA and the other 5 variants of SCA.The results show that RDSCA has competitive results with other metaheuristics algorithms. 展开更多
关键词 sine cosine algorithm global optimization swarm intelligence meta-heuristic algorithms
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Shape and Size Optimization of Truss Structures under Frequency Constraints Based on Hybrid Sine Cosine Firefly Algorithm
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作者 Ran Tao Xiaomeng Yang +1 位作者 Huanlin Zhou Zeng Meng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第1期405-428,共24页
Shape and size optimization with frequency constraints is a highly nonlinear problem withmixed design variables,non-convex search space,and multiple local optima.Therefore,a hybrid sine cosine firefly algorithm(HSCFA)... Shape and size optimization with frequency constraints is a highly nonlinear problem withmixed design variables,non-convex search space,and multiple local optima.Therefore,a hybrid sine cosine firefly algorithm(HSCFA)is proposed to acquire more accurate solutions with less finite element analysis.The full attraction model of firefly algorithm(FA)is analyzed,and the factors that affect its computational efficiency and accuracy are revealed.A modified FA with simplified attraction model and adaptive parameter of sine cosine algorithm(SCA)is proposed to reduce the computational complexity and enhance the convergence rate.Then,the population is classified,and different populations are updated by modified FA and SCA respectively.Besides,the random search strategy based on Lévy flight is adopted to update the stagnant or infeasible solutions to enhance the population diversity.Elitist selection technique is applied to save the promising solutions and further improve the convergence rate.Moreover,the adaptive penalty function is employed to deal with the constraints.Finally,the performance of HSCFA is demonstrated through the numerical examples with nonstructural masses and frequency constraints.The results show that HSCFA is an efficient and competitive tool for shape and size optimization problems with frequency constraints. 展开更多
关键词 Firefly algorithm sine cosine algorithm frequency constraints structural optimization
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ON DOUBLE SINE AND COSINE TRANSFORMS,LIPSCHITZ AND ZYGMUND CLASSES
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作者 Vanda Flp Ferenc Móricz 《Analysis in Theory and Applications》 2011年第4期351-364,共14页
We consider complex-valued functions f ∈ L^1 (R^2+), where R+ := [0,∞), and prove sufficient conditions under which the double sine Fourier transform fss and the double cosine Fourier transform fcc belong to o... We consider complex-valued functions f ∈ L^1 (R^2+), where R+ := [0,∞), and prove sufficient conditions under which the double sine Fourier transform fss and the double cosine Fourier transform fcc belong to one of the two-dimensional Lipschitz classes Lip(a,β) for some 0 〈 α,β ≤ 1; or to one of the Zygmund classes Zyg(α,β) for some 0 〈 α,β ≤ 2. These sufficient conditions are best possible in the sense that they are also necessary for nonnegative-valued functions f ∈ L^1 (R^2+). 展开更多
关键词 double sine and cosine Fourier transform Lipschitz class Lip(α β) 0 α β 1 Zygmund class Zyg( α β) 0 α β ≤2.
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Hybrid Sine Cosine and Stochastic Fractal Search for Hemoglobin Estimation
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作者 Marwa M.Eid Fawaz Alassery +3 位作者 Abdelhameed Ibrahim Bandar Abdullah Aloyaydi Hesham Arafat Ali Shady Y.El-Mashad 《Computers, Materials & Continua》 SCIE EI 2022年第8期2467-2482,共16页
The sample’s hemoglobin and glucose levels can be determined by obtaining a blood sample from the human body using a needle and analyzing it.Hemoglobin(HGB)is a critical component of the human body because it transpo... The sample’s hemoglobin and glucose levels can be determined by obtaining a blood sample from the human body using a needle and analyzing it.Hemoglobin(HGB)is a critical component of the human body because it transports oxygen from the lungs to the body’s tissues and returns carbon dioxide from the tissues to the lungs.Calculating the HGB level is a critical step in any blood analysis job.TheHGBlevels often indicate whether a person is anemic or polycythemia vera.Constructing ensemble models by combining two or more base machine learning(ML)models can help create a more improved model.The purpose of this work is to present a weighted average ensemble model for predicting hemoglobin levels.An optimization method is utilized to get the ensemble’s optimum weights.The optimum weight for this work is determined using a sine cosine algorithm based on stochastic fractal search(SCSFS).The proposed SCSFS ensemble is compared toDecision Tree,Multilayer perceptron(MLP),Support Vector Regression(SVR)and Random Forest Regressors as model-based approaches and the average ensemble model.The SCSFS results indicate that the proposed model outperforms existing models and provides an almost accurate hemoglobin estimate. 展开更多
关键词 sine cosine optimization metaheuristics optimization hemoglobin estimation weight average ensemble
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Discrete Convolution Associated with Fractional Cosine and Sine Series
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作者 Xiuxiu Gao Qiang Feng +1 位作者 Yinyin Mei Yi Xiang 《Journal of Beijing Institute of Technology》 EI CAS 2021年第3期305-310,共6页
Fractional sine series(FRSS)and fractional cosine series(FRCS)are the discrete form of the fractional cosine transform(FRCT)and fractional sine transform(FRST).The recent stud-ies have shown that discrete convolution ... Fractional sine series(FRSS)and fractional cosine series(FRCS)are the discrete form of the fractional cosine transform(FRCT)and fractional sine transform(FRST).The recent stud-ies have shown that discrete convolution is widely used in optics,signal processing and applied mathematics.In this paper,firstly,the definitions of fractional sine series(FRSS)and fractional co-sine series(FRCS)are presented.Secondly,the discrete convolution operations and convolution theorems for fractional sine and cosine series are given.The relationship of two convolution opera-tions is presented.Lastly,the discrete Young’s type inequality is established.The proposed theory plays an important role in digital filtering and the solution of differential and integral equations. 展开更多
关键词 fractional cosine series fractional sine series discrete convolution discrete Young’s in-equality
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A Hybrid Modified Sine Cosine Algorithm Using Inverse Filtering and Clipping Methods for Low Autocorrelation Binary Sequences
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作者 Siti Julia Rosli Hasliza A Rahim +8 位作者 Khairul Najmy Abdul Rani Ruzelita Ngadiran Wan Azani Mustafa Muzammil Jusoh Mohd Najib Mohd Yasin Thennarasan Sabapathy Mohamedfareq Abdulmalek Wan Suryani Firuz Wan Ariffin Ahmed Alkhayyat 《Computers, Materials & Continua》 SCIE EI 2022年第5期3533-3556,共24页
The essential purpose of radar is to detect a target of interest and provide information concerning the target’s location,motion,size,and other parameters.The knowledge about the pulse trains’properties shows that a... The essential purpose of radar is to detect a target of interest and provide information concerning the target’s location,motion,size,and other parameters.The knowledge about the pulse trains’properties shows that a class of signals is mainly well suited to digital processing of increasing practical importance.A low autocorrelation binary sequence(LABS)is a complex combinatorial problem.The main problems of LABS are low Merit Factor(MF)and shorter length sequences.Besides,the maximum possible MF equals 12.3248 as infinity length is unable to be achieved.Therefore,this study implemented two techniques to propose a new metaheuristic algorithm based on Hybrid Modified Sine Cosine Algorithm with Cuckoo Search Algorithm(HMSCACSA)using Inverse Filtering(IF)and clipping method to achieve better results.The proposed algorithms,LABS-IF and HMSCACSA-IF,achieved better results with two large MFs equal to 12.12 and 12.6678 for lengths 231 and 237,respectively,where the optimal solutions belong to the skew-symmetric sequences.The MF outperformed up to 24.335%and 2.708%against the state-of-the-art LABS heuristic algorithm,xLastovka,and Golay,respectively.These results indicated that the proposed algorithm’s simulation had quality solutions in terms of fast convergence curve with better optimal means,and standard deviation. 展开更多
关键词 Merit factor AUTOCORRELATION skew-symmetric sequences combinatorial optimization sine cosine algorithm cuckoo search algorithm radar system wearable antenna antenna and propagation
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广义块Toeplitz特征值问题的基于sine变换的预处理子(英文)
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作者 王元媛 卢琳璋 《数学研究》 CSCD 2008年第3期240-250,共11页
在求块Toeplitz矩阵束(A_(mn),B_(mn))特征值的Lanczos过程中,通过对移位块Toepltz矩阵A_(mn)-ρB_(mn)进行基于sine变换的块预处理,从而改进了位移块Toeplitz矩阵的谱分布,加速了Lanczos过程的收敛速度.该块预处理方法能通过快速算法... 在求块Toeplitz矩阵束(A_(mn),B_(mn))特征值的Lanczos过程中,通过对移位块Toepltz矩阵A_(mn)-ρB_(mn)进行基于sine变换的块预处理,从而改进了位移块Toeplitz矩阵的谱分布,加速了Lanczos过程的收敛速度.该块预处理方法能通过快速算法有效快速执行.本文证明了预处理后Lanczos过程收敛迅速,并通过实验证明该算法求解大规模矩阵问题尤其有效. 展开更多
关键词 分块Toeplitz矩阵 双对称 sine变换 预处理Lanczos方法
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Hankel矩阵离散Sine变换的快速算法
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作者 曾祝明 《常熟理工学院学报》 2009年第4期25-28,共4页
利用Hankel矩阵的结构特点导出一递推关系式,给出了Hankel矩阵离散Sine变换(DST)的一个快速算法.该算法所需要的存贮空间为O(N),计算变换矩阵的M个元素所需的计算量为O (NlogN)+O(M).
关键词 HANKEL矩阵 离散sine变换(DST) 快速算法
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利用有限正弦和有限余弦变换模拟地震波场:声波方程 被引量:7
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作者 孙建国 王雪秋 《吉林大学学报(地球科学版)》 EI CAS CSCD 北大核心 2006年第1期108-112,共5页
研究了一种利用有限正弦和有限余弦变换解变密度声波方程的方法,它的基本思想有下列4点:(1)对声波方程两端进行关于一个或多个变量的有限正弦或有限余弦变换;(2)将待求波场的Fourier正弦或余弦级数表达式代入到经过变换后的波动方程之中... 研究了一种利用有限正弦和有限余弦变换解变密度声波方程的方法,它的基本思想有下列4点:(1)对声波方程两端进行关于一个或多个变量的有限正弦或有限余弦变换;(2)将待求波场的Fourier正弦或余弦级数表达式代入到经过变换后的波动方程之中,进而得到级数表达系数所满足的微分方程式;(3)分别对时间和未作变换的空间导数进行有限差分或其它形式的近似,得到变换系数所满足的离散(矩阵)方程;(4)将通过解离散(矩阵)方程而得到的变换系数代入到相应的反演公式中去,用求和的方式得到待求波场的数值解。与其它方法相比,利用有限正弦和有限余弦的优点在于可以无限制地扩展变换方向的计算区间和可以处理任意变化的速度和密度结构而不明显地增加计算量。 展开更多
关键词 有限正弦和有限余弦变化变换 地震波场数值模拟 强速度变化
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线性正则正弦与余弦变换的卷积定理及其应用 被引量:4
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作者 王荣波 冯强 《光电工程》 CAS CSCD 北大核心 2018年第6期69-78,共10页
针对奇、偶信号的去噪问题,提出了一种基于线性正则正(余)弦变换卷积定理的乘性滤波器设计方法。在现有线性正则变换域卷积理论的基础上,研究了两类线性正则正(余)弦变换卷积定理,利用所得卷积定理,通过合理选择滤波函数,设计了一类基... 针对奇、偶信号的去噪问题,提出了一种基于线性正则正(余)弦变换卷积定理的乘性滤波器设计方法。在现有线性正则变换域卷积理论的基础上,研究了两类线性正则正(余)弦变换卷积定理,利用所得卷积定理,通过合理选择滤波函数,设计了一类基于卷积定理的线性正则正(余)弦变换域带限信号的乘性滤波模型,并对算法的复杂度进行分析。研究表明,这种滤波模型特别适合处理奇、偶信号,并能有效降低乘积滤波的计算复杂度,提高运算效率。 展开更多
关键词 线性正则变换 线性正则正(余)弦变换 卷积定理 滤波
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实对称正定Toeplitz矩阵的带位移的Sine预处理子 被引量:3
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作者 刘仲云 吴念慈 +1 位作者 秦小蓉 张育林 《数学理论与应用》 2017年第1期1-6,共6页
本文研究了求解实对称正定Toeplitz线性方程组的预处理共轭梯度法.基于实对称Toeplitz矩阵都有一个三角变换分裂(TTS)的事实,我们提出了带位移的Sine预处理子TS,分析了预处理矩阵的谱性质,并讨论了每步迭代的计算复杂度.数值实验表明该... 本文研究了求解实对称正定Toeplitz线性方程组的预处理共轭梯度法.基于实对称Toeplitz矩阵都有一个三角变换分裂(TTS)的事实,我们提出了带位移的Sine预处理子TS,分析了预处理矩阵的谱性质,并讨论了每步迭代的计算复杂度.数值实验表明该预处理子比T.Chan预处理子^([2])更有效. 展开更多
关键词 TOEPLITZ矩阵 三角变换分裂 带位移的sine预处理子 预处理共轭梯度方法
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