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A multiscale adaptive framework based on convolutional neural network:Application to fluid catalytic cracking product yield prediction
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作者 Nan Liu Chun-Meng Zhu +1 位作者 Meng-Xuan Zhang Xing-Ying Lan 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2849-2869,共21页
Since chemical processes are highly non-linear and multiscale,it is vital to deeply mine the multiscale coupling relationships embedded in the massive process data for the prediction and anomaly tracing of crucial pro... Since chemical processes are highly non-linear and multiscale,it is vital to deeply mine the multiscale coupling relationships embedded in the massive process data for the prediction and anomaly tracing of crucial process parameters and production indicators.While the integrated method of adaptive signal decomposition combined with time series models could effectively predict process variables,it does have limitations in capturing the high-frequency detail of the operation state when applied to complex chemical processes.In light of this,a novel Multiscale Multi-radius Multi-step Convolutional Neural Network(Msrt Net)is proposed for mining spatiotemporal multiscale information.First,the industrial data from the Fluid Catalytic Cracking(FCC)process decomposition using Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)extract the multi-energy scale information of the feature subset.Then,convolution kernels with varying stride and padding structures are established to decouple the long-period operation process information encapsulated within the multi-energy scale data.Finally,a reconciliation network is trained to reconstruct the multiscale prediction results and obtain the final output.Msrt Net is initially assessed for its capability to untangle the spatiotemporal multiscale relationships among variables in the Tennessee Eastman Process(TEP).Subsequently,the performance of Msrt Net is evaluated in predicting product yield for a 2.80×10^(6) t/a FCC unit,taking diesel and gasoline yield as examples.In conclusion,Msrt Net can decouple and effectively extract spatiotemporal multiscale information from chemical process data and achieve a approximately reduction of 30%in prediction error compared to other time-series models.Furthermore,its robustness and transferability underscore its promising potential for broader applications. 展开更多
关键词 Fluid catalytic cracking product yield Data-driven modeling Multiscale prediction Data decomposition convolution neural network
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Blind reconstruction of convolutional code based on segmented Walsh-Hadamard transform 被引量:10
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作者 Fenghua Wang Hui Xie Zhitao Huang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期748-754,共7页
Walsh-Hadamard transform (WriT) can solve linear error equations on Field F2, and the method can be used to recover the parameters of convolutional code. However, solving the equations with many unknowns needs enorm... Walsh-Hadamard transform (WriT) can solve linear error equations on Field F2, and the method can be used to recover the parameters of convolutional code. However, solving the equations with many unknowns needs enormous computer memory which limits the application of WriT. In order to solve this problem, a method based on segmented WriT is proposed in this paper. The coefficient vector of high dimension is reshaped and two vectors of lower dimension are obtained. Then the WriT is operated and the requirement for computer memory is much reduced. The code rate and the constraint length of convolutional code are detected from the Walsh spectrum. And the check vector is recovered from the peak position. The validity of the method is verified by the simulation result, and the performance is proved to be optimal. 展开更多
关键词 convolutional code blind reconstruction Walsh-hadamard transform (WriT) tinear error equation.
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A production prediction method of single well in water flooding oilfield based on integrated temporal convolutional network model 被引量:2
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作者 ZHANG Lei DOU Hongen +6 位作者 WANG Tianzhi WANG Hongliang PENG Yi ZHANG Jifeng LIU Zongshang MI Lan JIANG Liwei 《Petroleum Exploration and Development》 CSCD 2022年第5期1150-1160,共11页
Since the oil production of single well in water flooding reservoir varies greatly and is hard to predict, an oil production prediction method of single well based on temporal convolutional network(TCN) is proposed an... Since the oil production of single well in water flooding reservoir varies greatly and is hard to predict, an oil production prediction method of single well based on temporal convolutional network(TCN) is proposed and verified. This method is started from data processing, the correspondence between water injectors and oil producers is determined according to the influence radius of the water injectors, the influence degree of a water injector on an oil producer in the month concerned is added as a model feature, and a Random Forest(RF) model is built to fill the dynamic data of water flooding. The single well history is divided into 4 stages according to its water cut, that is, low water cut, middle water cut, high water cut and extra-high water cut stages. In each stage, a TCN based prediction model is established, hyperparameters of the model are optimized by the Sparrow Search Algorithm(SSA). Finally, the models of the 4 stages are integrated into one whole-life model of the well for production prediction. The application of this method in Daqing Oilfield, NE China shows that:(1) Compared with conventional data processing methods, the data obtained by this processing method are more close to the actual production, and the data set obtained is more authentic and complete.(2) The TCN model has higher prediction accuracy than other 11 models such as Long Short Term Memory(LSTM).(3) Compared with the conventional full-life-cycle models, the model of integrated stages can significantly reduce the error of production prediction. 展开更多
关键词 single well production prediction temporal convolutional network time series prediction water flooding reservoir
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Fine-Grained Classification of Product Images Based on Convolutional Neural Networks 被引量:1
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作者 Tongtong Liu Rubing Wang +2 位作者 Jikang Chen Shengliang Han Jimin Yang 《Advances in Molecular Imaging》 2018年第4期69-87,共19页
With the rapid development of the Internet of things and e-commerce, feature-based image retrieval and classification have become a serious challenge for shoppers searching websites for relevant product information. T... With the rapid development of the Internet of things and e-commerce, feature-based image retrieval and classification have become a serious challenge for shoppers searching websites for relevant product information. The last decade has witnessed great interest in research on content-based feature extraction techniques. Moreover, semantic attributes cannot fully express the rich image information. This paper designs and trains a deep convolutional neural network that the convolution kernel size and the order of network connection are based on the high efficiency of the filter capacity and coverage. To solve the problem of long training time and high resource share of deep convolutional neural network, this paper designed a shallow convolutional neural network to achieve the similar classification accuracy. The deep and shallow convolutional neural networks have data pre-processing, feature extraction and softmax classification. To evaluate the classification performance of the network, experiments were conducted using a public database Caltech256 and a homemade product image database containing 15 species of garment and 5 species of shoes on a total of 20,000 color images from shopping websites. Compared with the classification accuracy of combining content-based feature extraction techniques with traditional support vector machine techniques from 76.3% to 86.2%, the deep convolutional neural network obtains an impressive state-of-the-art classification accuracy of 92.1%, and the shallow convolutional neural network reached a classification accuracy of 90.6%. Moreover, the proposed convolutional neural networks can be integrated and implemented in other colour image database. 展开更多
关键词 product CLASSIFICATION FEATURE Extraction convolutional NEURAL Network (CNN) Softmax
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Blind recognition of k/n rate convolutional encoders from noisy observation 被引量:13
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作者 Li Huang Wengu Chen +1 位作者 Enhong Chen Hong Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第2期235-243,共9页
Blind recognition of convolutional codes is not only essential for cognitive radio, but also for non-cooperative context. This paper is dedicated to the blind identification of rate k/n convolutional encoders in a noi... Blind recognition of convolutional codes is not only essential for cognitive radio, but also for non-cooperative context. This paper is dedicated to the blind identification of rate k/n convolutional encoders in a noisy context based on Walsh-Hadamard transformation and block matrix (WHT-BM). The proposed algorithm constructs a system of noisy linear equations and utilizes all its coefficients to recover parity check matrix. It is able to make use of fault-tolerant feature of WHT, thus providing more accurate results and achieving better error performance in high raw bit error rate (BER) regions. Moreover, it is more computationally efficient with the use of the block matrix (BM) method. © 2017 Beijing Institute of Aerospace Information. 展开更多
关键词 Cognitive radio convolution convolutional codes Error correction hadamard matrices hadamard transforms Linear transformations Mathematical transformations Matrix algebra Signal encoding
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M-矩阵Hadamard积最小特征值下界的改进
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作者 周平 《文山学院学报》 2024年第5期54-57,共4页
针对非奇异M-矩阵和M-矩阵的逆矩阵Hadamard积的最小特征值下界问题,结合M-矩阵的逆矩阵元素的上界、特征值包含域定理以及不等式放缩技巧,获得两个容易计算的、具有可调节参数且只与矩阵元素相关的新估计式,同时给出当A-1是双随机矩阵... 针对非奇异M-矩阵和M-矩阵的逆矩阵Hadamard积的最小特征值下界问题,结合M-矩阵的逆矩阵元素的上界、特征值包含域定理以及不等式放缩技巧,获得两个容易计算的、具有可调节参数且只与矩阵元素相关的新估计式,同时给出当A-1是双随机矩阵时的两个改进的估计式,并通过理论分析和数值例子对比表明新下界比已有的结果更精确,具有一定的优越性和有效性。 展开更多
关键词 M-矩阵 hadamard 双随机矩阵 最小特征值 新下界
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On the Coefficients of Several Classes of Bi-univalent Functions Defined by Convolution 被引量:5
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作者 Guo Dong Li Zong-tao 《Communications in Mathematical Research》 CSCD 2018年第1期65-76,共12页
In this paper, we introduce several new subclasses of the function class Σ of bi-univalent functions analytic in the open unit disc defined by convolution.Furthermore, we investigate the bounds of the coefficients |a... In this paper, we introduce several new subclasses of the function class Σ of bi-univalent functions analytic in the open unit disc defined by convolution.Furthermore, we investigate the bounds of the coefficients |a2| and |a3| for functions in these new subclasses. The results presented in this paper improve or generalize the recent works of other authors. 展开更多
关键词 analytic and univalent functions coefficient bi-univalent function hadamard product convolution
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Matrix Inequalities for the Fan Product and the Hadamard Product of Matrices 被引量:6
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作者 Dongjie Gao 《Advances in Linear Algebra & Matrix Theory》 2015年第3期90-97,共8页
A new inequality on the minimum eigenvalue for the Fan product of nonsingular M-matrices is given. In addition, a new inequality on the spectral radius of the Hadamard product of nonnegative matrices is also obtained.... A new inequality on the minimum eigenvalue for the Fan product of nonsingular M-matrices is given. In addition, a new inequality on the spectral radius of the Hadamard product of nonnegative matrices is also obtained. These inequalities can improve considerably some previous results. 展开更多
关键词 M-MATRIX NONNEGATIVE Matrix FAN product hadamard product Spectral Radius Minimum EIGENVALUE
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A new model of the harmonic control based on Hadamard product
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作者 Xinjin LIU Yun ZOU Xiefei YAN 《控制理论与应用(英文版)》 EI 2009年第4期433-437,共5页
In terms of Hadamard product, a new model is proposed for the control of connection coefficients of the state variables of the systems. The control law to stabilize the systems via the regulations of connection coeffi... In terms of Hadamard product, a new model is proposed for the control of connection coefficients of the state variables of the systems. The control law to stabilize the systems via the regulations of connection coefficients is obtained via a Hadamard product involved bilinear matrix inequalities. This new control model may be of significant applications in many fields, especially may be of some special sense in the emergency control such as isolation and obstruction control. 展开更多
关键词 hadamard synergic stabilization problem Harmonic control Isolation and obstruction control hadamard product
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LIE-TROTTER FORMULA FOR THE HADAMARD PRODUCT
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作者 Jing WANG Yonggang LI Huafei SUN 《Acta Mathematica Scientia》 SCIE CSCD 2020年第3期659-669,共11页
Suppose that A and B are two positive-definite matrices,then,the limit of(A^p/2B^pA^p/2)1/p as p tends to 0 can be obtained by the well known Lie-Trotter formula.In this article,we generalize the usual product of matr... Suppose that A and B are two positive-definite matrices,then,the limit of(A^p/2B^pA^p/2)1/p as p tends to 0 can be obtained by the well known Lie-Trotter formula.In this article,we generalize the usual product of matrices to the Hadamard product denoted as*which is commutative,and obtain the explicit formula of the limit(A^p*B^p)^1/p as p tends to 0.Furthermore,the existence of the limit of(A^p*B^p)^1/p as p tends to+∞is proved. 展开更多
关键词 Lie-Trotter formula reciprocal Lie-Trotter formula hadamard product positive-definite matrix
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A CONJECTURE CONCERNING THE HADAMARD PRODUCT OF INVERSE M-MATRICES
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作者 Zhou Yuzhong(Dept.of Math.,South China Normal University,Guangzhou 510631,PRC) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第S1期113-114,共2页
1 IntroductionFor an n×n matrix A which is an inverse M-matrix,M.Neumann in [1]conjecturedthat the Hadamard product A·A is an inverse of an M-matrix.They have checked hisconjecture without failure on Ultrame... 1 IntroductionFor an n×n matrix A which is an inverse M-matrix,M.Neumann in [1]conjecturedthat the Hadamard product A·A is an inverse of an M-matrix.They have checked hisconjecture without failure on Ultrametric matrices and inverse of MMA-matrices,Uni-pathicmatrices and the Willongby inverse M-matrices.Bo-Ying Wang et al.in[2]haveinvestigated Triangular inverse M-matrices which are closed under the Hadamard multipli-cation.Lu Linzheng,Sun Weiwei and Li Wen in[3]presented a more general 展开更多
关键词 WANG A CONJECTURE CONCERNING THE hadamard product OF INVERSE M-MATRICES ZHANG MORE
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Generalized Inversions of Hadamard and Tensor Products for Matrices
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作者 Saburou Saitoh 《Advances in Linear Algebra & Matrix Theory》 2014年第2期87-95,共9页
We shall give natural generalized solutions of Hadamard and tensor products equations for matrices by the concept of the Tikhonov regularization combined with the theory of reproducing kernels.
关键词 Reproducing Kernel Positive Definite HERMITIAN MATRIX Tensor product hadamard product GENERALIZED Inverse MATRIX Equation Tikhonov Regularization 100/0 = 0 0/0 = 0 GENERALIZED Fraction GENERALIZED Fractional Function
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The Exact Solutions of Such Coupled Linear Matrix Fractional Differential Equations of Diagonal Unknown Matrices by Using Hadamard Product
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作者 Zayed Al-Zuhiri Zeyad Al-Zhour Khaled Jaber 《Journal of Applied Mathematics and Physics》 2016年第2期432-442,共11页
In this paper, we present the general exact solutions of such coupled system of matrix fractional differential equations for diagonal unknown matrices in Caputo sense by using vector extraction operators and Hadamard ... In this paper, we present the general exact solutions of such coupled system of matrix fractional differential equations for diagonal unknown matrices in Caputo sense by using vector extraction operators and Hadamard product. Some illustrated examples are also given to show our new approach. 展开更多
关键词 Fractional Operators Matrix Fractional Differential Equations hadamard product Vector Extraction Operator
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A REMARK ON CERTAIN CONVOLUTION OPERATOR
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作者 刘金林 《苏州大学学报(自然科学版)》 CAS 1993年第2期128-130,共3页
A certain operator D^(a+p-1) defined by convolutions (or Hadamard products) is introduced. The object of this paper is to give an application of the convolution operator D^(a+p-1) to the differential inequalities.
关键词 卷积 不等式 函数分析 hadamard积分
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Identifying Brand Consistency by Product Differentiation Using CNN
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作者 Hung-Hsiang Wang Chih-Ping Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期685-709,共25页
This paper presents a new method of using a convolutional neural network(CNN)in machine learning to identify brand consistency by product appearance variation.In Experiment 1,we collected fifty mouse devices from the ... This paper presents a new method of using a convolutional neural network(CNN)in machine learning to identify brand consistency by product appearance variation.In Experiment 1,we collected fifty mouse devices from the past thirty-five years from a renowned company to build a dataset consisting of product pictures with pre-defined design features of their appearance and functions.Results show that it is a challenge to distinguish periods for the subtle evolution of themouse devices with such traditionalmethods as time series analysis and principal component analysis(PCA).In Experiment 2,we applied deep learning to predict the extent to which the product appearance variation ofmouse devices of various brands.The investigation collected 6,042 images ofmouse devices and divided theminto the Early Stage and the Late Stage.Results show the highest accuracy of 81.4%with the CNNmodel,and the evaluation score of brand style consistency is 0.36,implying that the brand consistency score converted by the CNN accuracy rate is not always perfect in the real world.The relationship between product appearance variation,brand style consistency,and evaluation score is beneficial for predicting new product styles and future product style roadmaps.In addition,the CNN heat maps highlight the critical areas of design features of different styles,providing alternative clues related to the blurred boundary.The study provides insights into practical problems for designers,manufacturers,and marketers in product design.It not only contributes to the scientific understanding of design development,but also provides industry professionals with practical tools and methods to improve the design process and maintain brand consistency.Designers can use these techniques to find features that influence brand style.Then,capture these features as innovative design elements and maintain core brand values. 展开更多
关键词 Machine learning product differentiation brand consistency principal component analysis convolutional neural network computer mouse
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从三个角度考察Hadamard不等式
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作者 咸伟志 周明亮 《佳木斯大学学报(自然科学版)》 CAS 2024年第6期164-168,共5页
高等代数、数学分析以及解析几何是大学数学专业的三门基础课程,它们在理论基础、问题处理方法等方面存在差异,然而相互之间存在协同作用,相互渗透。Hadamard不等式是高等数学中一项重要的代数不等式。相较于以往单一代数视角的研究,本... 高等代数、数学分析以及解析几何是大学数学专业的三门基础课程,它们在理论基础、问题处理方法等方面存在差异,然而相互之间存在协同作用,相互渗透。Hadamard不等式是高等数学中一项重要的代数不等式。相较于以往单一代数视角的研究,本文旨在从高等代数、数学分析和解析几何这三门数学专业基础课程的不同视角探讨Hadamard不等式的成立,并分析在不同视角下证明该不等式的差异和联系。 展开更多
关键词 hadamard不等式 行列式 拉格朗日乘数法 欧氏空间 叉积
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基于Walsh-Hadamard变换的卷积码盲识别 被引量:83
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作者 刘健 王晓君 周希元 《电子与信息学报》 EI CSCD 北大核心 2010年第4期884-888,共5页
该文针对信道编码的盲识别问题,提出了高误码率下(n,1,m)卷积码的盲识别方法。首先给出了盲识别的数学模型,进而扩展了Walsh-Hadamard变换的应用范围。证明了通过对截获码序列做Walsh-Hadamard变换可以解决卷积码的盲识别问题,该方法在... 该文针对信道编码的盲识别问题,提出了高误码率下(n,1,m)卷积码的盲识别方法。首先给出了盲识别的数学模型,进而扩展了Walsh-Hadamard变换的应用范围。证明了通过对截获码序列做Walsh-Hadamard变换可以解决卷积码的盲识别问题,该方法在智能通信、信息截获、密码分析等领域有重要的应用。仿真实验表明该算法可以对高误码率的卷积码进行有效的识别。 展开更多
关键词 盲识别 卷积码 高误码率 Walsh-hadamard变换
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矩阵Hadamard积和Fan积的特征值界的一些新估计式(英文) 被引量:11
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作者 陈付彬 任献花 郝冰 《数学杂志》 CSCD 北大核心 2014年第5期895-903,共9页
本文研究了非奇异M-矩阵A与B的Fan积的最小特征值下界和非负矩阵A与B的Hadamard积的谱半径上界的估计问题.利用Brauer定理,得到了一些只依赖于矩阵的元素且易于计算的新估计式,改进了文献[41现有的一些结果.
关键词 M-矩阵 非负矩阵 hadamard Fan积 谱半径 最小特征值
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M-矩阵与其逆矩阵的Hadamard积最小特征值下界的估计 被引量:12
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作者 杨晓英 韩惠丽 刘新 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2013年第6期50-53,共4页
关于M-矩阵A与其逆矩阵的Hadamard积AA-1,利用Gerschgorin圆盘定理给出了AA-1的最小特征值下界的一些新的估计式,改进了Fiedler和Markham的猜想.
关键词 hadamard M-矩阵 最小特征值 下界 逆矩阵
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基于分段抽取软判决加权Walsh Hadamard变换的卷积码识别算法 被引量:6
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作者 张岱 张玉 +1 位作者 杨晓静 樊斌斌 《兵工学报》 EI CAS CSCD 北大核心 2015年第12期2298-2305,共8页
针对低信噪比环境下卷积码识别研究存在的不足,提出一种基于分段抽取软判决加权Walsh Hadamard变换(WHT)的卷积码识别算法。该算法利用接收比特的解调软判决信息求取软判决频次序列,并构造加权Walsh Hadamard矩阵,从而识别得到基本校验... 针对低信噪比环境下卷积码识别研究存在的不足,提出一种基于分段抽取软判决加权Walsh Hadamard变换(WHT)的卷积码识别算法。该算法利用接收比特的解调软判决信息求取软判决频次序列,并构造加权Walsh Hadamard矩阵,从而识别得到基本校验序列。利用基本编码矩阵构造规则,最终实现记忆长度及基本生成矩阵的识别。算法结合分段抽取思想,降低了所需运行存储量。仿真实验表明,该算法可在低信噪比环境下对不同码率卷积码进行有效识别,具有较好的容错性,且对大约束度的卷积码性能提高更为显著。 展开更多
关键词 信息处理技术 卷积码识别 低信噪比 软判决信息 加权Walsh hadamard变换 分段抽取
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