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Phase spectrum estimation of the seismic wavelet based on a criterion function 被引量:4
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作者 Yu Yongcai Wang Shangxu +1 位作者 Yuan Sanyi Qi Pengfei 《Petroleum Science》 SCIE CAS CSCD 2012年第2期170-181,共12页
Phase spectrum estimation of the seismic wavelet is an important issue in high-resolution seismic data processing and interpretation. On the basis of two patterns of constant-phase rotation and root transform for wave... Phase spectrum estimation of the seismic wavelet is an important issue in high-resolution seismic data processing and interpretation. On the basis of two patterns of constant-phase rotation and root transform for wavelet phase spectrum variation, we introduce six sparse criteria, including Lu’s improved kurtosis criterion, the parsimony criterion, exponential transform criterion, Sech criterion, Cauchy criterion, and the modified Cauchy criterion, to phase spectrum estimation of the seismic wavelet, obtaining an equivalent effect to the kurtosis criterion. Through numerical experiments, we find that when the reflectivity is not a sparse sequence, the estimated phase spectrum of the seismic wavelet based on the criterion function will deviate from the true value. In order to eliminate the influence of non-sparse reflectivity series in a single trace, we apply the method to the multi-trace seismogram, improving the accuracy of seismic wavelet phase spectrum estimation. 展开更多
关键词 Seismic wavelet phase spectrum criterion function SPARSE
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Kernel matrix learning with a general regularized risk functional criterion 被引量:3
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作者 Chengqun Wang Jiming Chen +1 位作者 Chonghai Hu Youxian Sun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第1期72-80,共9页
Kernel-based methods work by embedding the data into a feature space and then searching linear hypothesis among the embedding data points. The performance is mostly affected by which kernel is used. A promising way is... Kernel-based methods work by embedding the data into a feature space and then searching linear hypothesis among the embedding data points. The performance is mostly affected by which kernel is used. A promising way is to learn the kernel from the data automatically. A general regularized risk functional (RRF) criterion for kernel matrix learning is proposed. Compared with the RRF criterion, general RRF criterion takes into account the geometric distributions of the embedding data points. It is proven that the distance between different geometric distdbutions can be estimated by their centroid distance in the reproducing kernel Hilbert space. Using this criterion for kernel matrix learning leads to a convex quadratically constrained quadratic programming (QCQP) problem. For several commonly used loss functions, their mathematical formulations are given. Experiment results on a collection of benchmark data sets demonstrate the effectiveness of the proposed method. 展开更多
关键词 kernel method support vector machine kernel matrix learning HKRS geometric distribution regularized risk functional criterion.
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CRITERION AND APPRAISABLE FUNCTION OF SIZE CHARACTERISTICS
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作者 Xie, Hengxing Yi, Guohong Li, Songren 《中国有色金属学会会刊:英文版》 EI CSCD 1997年第1期9-13,共5页
CRITERIONANDAPPRAISABLEFUNCTIONOFSIZECHARACTERISTICS①XieHengxing,YiGuohong,LiSongrenDepartmentofMineralEngin... CRITERIONANDAPPRAISABLEFUNCTIONOFSIZECHARACTERISTICS①XieHengxing,YiGuohong,LiSongrenDepartmentofMineralEngineering,CentralSou... 展开更多
关键词 SIZE SIZE CHARACTERISTICS criterion appraisable function
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A Criterion for Determining the Number of Clusters 被引量:1
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作者 郝立丽 郝立柱 《Northeastern Mathematical Journal》 CSCD 2008年第6期534-544,共11页
Aiming to provide an appropriate number K of clusters, in this paper, we propose a new criterion function - H criterion function, whose three properties have also been proved. We validate the performance of the H crit... Aiming to provide an appropriate number K of clusters, in this paper, we propose a new criterion function - H criterion function, whose three properties have also been proved. We validate the performance of the H criterion function on one artificial dataset and three real-world datasets, and the results are almostly consistent with a previous method. The nonparametric criterion we proposed is intuitive, simple and the computational cost is acceptable. 展开更多
关键词 hierarchical clustering H criterion function invariance of linear transformation
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Probability Criterion for a Dynamic Financial Model with Short-Selling Allowed
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作者 韩其恒 唐万生 李光泉 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第1期18-23,共6页
Probability criterion has its practical significance, and its investment decision-making is determined by the expected discounted wealth. In a complete, standard financial market with short-selling allowed, this paper... Probability criterion has its practical significance, and its investment decision-making is determined by the expected discounted wealth. In a complete, standard financial market with short-selling allowed, this paper probes into the investment decision-making with probability criterion. The upper limit of criterion function is obtained. The corresponding discounted wealth process and hedging portfolio process are provided. Finally, an illustrative example of one-dimensional constant-coefficient financial market is given. 展开更多
关键词 Probability criterion SHORT-SELLING criterion function Hedging portfolio process.
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Normal Families of Holomorphic Functions Concerning Zero Numbers 被引量:1
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作者 Yang Qi 《Communications in Mathematical Research》 CSCD 2018年第2期97-105,共9页
In this paper, we study the normal families related with a Hayman conjecture of higher derivative concerning zero numbers, and get one normal criteria.Our result improve some earlier related result.
关键词 holomorphic function shared value normal criterion
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The Normal Meromorphic Functions Family Concerning Higher Order Derivative and Shared Set by One-Way 被引量:1
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作者 Yi Li 《Advances in Pure Mathematics》 2011年第6期322-324,共3页
Let F be a meromorphic functions family on the unit disc Δ, If for every (the zeros of f is a multiplicity of at least k) and if then and ( ), then F is normal on Δ.
关键词 MEROMORPHIC function NORMALITY criterion SHARED Set by One-Way Higher Order DERIVATIVE
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Normality Criteria of Meromorphic Functions Concerning Shared Fixed-points 被引量:1
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作者 杨祺 《Chinese Quarterly Journal of Mathematics》 2015年第1期20-29,共10页
In this paper, we study the normality criteria of meromorphic functions concerning shared fixed-points, we obtain: Let F be a family of meromorphic functions defined in a domain D. Let n, k ≥ 2 be two positive intege... In this paper, we study the normality criteria of meromorphic functions concerning shared fixed-points, we obtain: Let F be a family of meromorphic functions defined in a domain D. Let n, k ≥ 2 be two positive integers. For every f ∈ F, all of whose zeros have multiplicity at least (nk+2)/(n-1). If f(f(k))nand g(g(k))nshare z in D for each pair of functions f and g, then F is normal. 展开更多
关键词 meromorphic function FIXED-POINTS shared value normal criterion
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The Value Distribution and Normality Criteria of a Class of Meromorphic Functions
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作者 Yang Qi 《Communications in Mathematical Research》 CSCD 2017年第1期53-63,共11页
In this article,we use Zalcman Lemma to investigate the normal family of meromorphic functions concerning shared values,which improves some earlier related results.
关键词 meromorphic function shared value normal criterion
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Normality Criteria of Meromorphic Functions
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作者 WANG QIONG YUAN WEN-JUN +1 位作者 CHEN WEI TIAN HONG-GEN 《Communications in Mathematical Research》 CSCD 2016年第1期88-96,共9页
In this paper, we consider normality criteria for a family of meromorphic functions concerning shared values. Let F be a family of meromorphic functions defined in a domain D, m, n, k and d be four positive integers s... In this paper, we consider normality criteria for a family of meromorphic functions concerning shared values. Let F be a family of meromorphic functions defined in a domain D, m, n, k and d be four positive integers satisfying m ≥ n + 2 and d≥k+1/m-n-1 and a(≠ 0), b be two finite constants. Suppose that every f∈F has all its zeros and poles of multiplicity at least k and d, respectively. If (fn)(k)-afm and (gn)(k) -agm share the value b for every pair of functions (f, g) of ~, then is normal in D. Our results improve the related theorems of Schwick (Schwick W. Normality criteria for families of meromorphic function. J. Anal. Math., 1989, 52: 241-289), Li and Gu (Li Y T, Gu Y X. On normal families of meromorphic functions. J. Math. Anal. Appl., 2009, 354: 421-425). 展开更多
关键词 meromorphic function shared value normal criterion
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Some Notes on Normality Criteria of Meromorphic Functions
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作者 CHEN WEI ZHANG YING-YING +1 位作者 TIAN HONG-GEN YUAN WEN-JUN 《Communications in Mathematical Research》 CSCD 2014年第1期81-89,共9页
In this paper, we study the normality of families of meromorohic functions related to a Hayman conjecture. We prove that the conditions in Hayman conjecture and in other criterions can be relaxed. The results in this ... In this paper, we study the normality of families of meromorohic functions related to a Hayman conjecture. We prove that the conditions in Hayman conjecture and in other criterions can be relaxed. The results in this paper improve some previous results. 展开更多
关键词 meromorphic function shared value normal criterion
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Derivation of Plastic Work Rate Done per Unit Volume for Mean Yield Criterion and Its Application 被引量:8
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作者 Dewen ZHAO Yingjie XIE +1 位作者 Xiaowen WANG Xianghua LIU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第4期433-436,共4页
In Haigh Westergaard stress space linear combination of twin shear stress and Tresca yield functions is called the mean yield (MY) criterion. The mathematical relationship of the criterion and its plastic work rate ... In Haigh Westergaard stress space linear combination of twin shear stress and Tresca yield functions is called the mean yield (MY) criterion. The mathematical relationship of the criterion and its plastic work rate done per unit volume were derived. A generalized worked example of slab forging was analyzed by the criterion and its corresponding plastic work rate done per unit volume. Then, the precision of the solution was compared with those by Mises and Twin shear stress yield criterions, respectively. It turned out that the calculated results by MY criterion were in good agreement with those by Mises criterion. 展开更多
关键词 Mean yield criterion Plastic work rate done per unit volume functional linearization Slab forging
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Normality of Meromorphic Functions Family and Shared Set by One-way
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作者 Yi Li 《Advances in Pure Mathematics》 2011年第3期95-98,共4页
We studied the normality criterion for families of meromorphic functions which related to One-way sharing set, and obtain two normal criterions, which improve the previous results.
关键词 MEROMORPHIC function NORMALITY criterion SHARED VALUES SHARED Set by One-way
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ANALYSIS OF A CRACK IN A FUNCTIONALLY GRADED STRIP WITH A POWER FORM SHEAR MODULUS 被引量:2
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作者 Jinju Ma Zheng Zhong Chuanzeng Zhang 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第5期465-473,共9页
The plane strain problem of a crack in a functionally graded strip with a power form shear modulus is studied. The governing equation in terms of Airy's stress function is solved exactly by means of Fourier transform... The plane strain problem of a crack in a functionally graded strip with a power form shear modulus is studied. The governing equation in terms of Airy's stress function is solved exactly by means of Fourier transform. The mixed boundary problem is then reduced to a system of singular integral equations and is solved numerically to obtain the stress intensity factor at crack-tip. The maximum circumferential stress criterion and the strain energy density criterion are both employed to predict the direction of crack initiation. Numerical examples are given to show the influence of the material gradation models and the crack sizes on the mode-I and mode-II stress intensity factors. The dependence of the critical kink-angle on the crack size is examined and it is found that the crack kink-angle decreases with the increase of the normalized crack length, indicating that a longer crack tends to follow the original crack-line while it is much easier for a shorter crack to deviate from the original crack-line. 展开更多
关键词 functionally graded material CRACK stress intensity factors fracture criterion
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Non-probabilistic Hydraulic Turbine Blade Vibration Reliability Research Based on Fuzzy Failure Criterion
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作者 庞煜 张翔 赖喜德 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期336-339,共4页
In hydraulic turbine engineering,turbine blade vibration reliability assessment is of great significance. Based on the interval mathematical theory, the variables existing in hydraulic turbine blade are described as i... In hydraulic turbine engineering,turbine blade vibration reliability assessment is of great significance. Based on the interval mathematical theory, the variables existing in hydraulic turbine blade are described as interval variables. Considering the fuzzy failure criterion of turbine blade distancing from resonance and vibration fatigue stress,fuzzy possibilistic reliability is expressed and analyzed qualitatively taking normal bathtub function as the membership function of blade resonance failure and deflection major type function as the membership function of the intensity failure. As a result,hydraulic turbine blade vibration reliability is analyzed based on the fuzziness of variables and failure criterion. A safer working environment is provided under possibility context by comparing with the qualitative conclusions in the past literature. 展开更多
关键词 fuzzy failure criterion interval variable fuzzy reliability membership function
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TAUBERIAN THEOREMS FOR WEAK ALMOST CONVERGENT FUNCTIONS
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作者 Meng-Kuang Kuo 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1203-1212,共10页
The almost convergent function which was introduced by Raimi [6] and discussed by Ho [4], Das and Nanda [2, 3], is the continuous analogue of almost convergent sequences (see [5]). In this paper, we establish the Ta... The almost convergent function which was introduced by Raimi [6] and discussed by Ho [4], Das and Nanda [2, 3], is the continuous analogue of almost convergent sequences (see [5]). In this paper, we establish the Tauberian conditions and the Cauchy criteria for weak almost convergent functions on R2+ . 展开更多
关键词 almost convergent functions weak almost convergent functions Tauberian theorems Cauchy criterions
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DETERMINING THE STRUCTURES AND PARAMETERS OF RADIAL BASIS FUNCTION NEURAL NETWORKS USING IMPROVED GENETIC ALGORITHMS 被引量:1
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作者 Meiqin Liu Jida Chen 《Journal of Central South University》 SCIE EI CAS 1998年第2期68-73,共6页
The method of determining the structures and parameters of radial basis function neural networks(RBFNNs) using improved genetic algorithms is proposed. Akaike′s information criterion (AIC) with generalization error t... The method of determining the structures and parameters of radial basis function neural networks(RBFNNs) using improved genetic algorithms is proposed. Akaike′s information criterion (AIC) with generalization error term is used as the best criterion of optimizing the structures and parameters of networks. It is shown from the simulation results that the method not only improves the approximation and generalization capability of RBFNNs ,but also obtain the optimal or suboptimal structures of networks. 展开更多
关键词 RADIAL BASIS function neural network GENETIC algorithms Akaike′s information criterion OVERFITTING
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Fisher准则函数在机械刀具切削磨损检测中的应用
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作者 任慧 马金萍 《机械设计与制造》 北大核心 2025年第1期154-159,165,共7页
在高精度机床道具切削磨损无接触图像检测中,磨损区域边缘特征容易发生混淆,区分其像素边缘区域成为一个难点。Fisher判别函数可以用于特征提取,即通过选择最具有区分力的特征来改善分类性能。针对这一特点,提出基于Fisher准则函数的机... 在高精度机床道具切削磨损无接触图像检测中,磨损区域边缘特征容易发生混淆,区分其像素边缘区域成为一个难点。Fisher判别函数可以用于特征提取,即通过选择最具有区分力的特征来改善分类性能。针对这一特点,提出基于Fisher准则函数的机械刀具切削磨损检测方法。首先,对采集到的机械刀具切削磨损图像实施图像增强处理,利用实施修正线性拉伸操作解决光照不均匀问题,凸出刀具磨损区域的细节特征并提高图像质量;其次,利用基于Fisher准则函数的图像阈值分割方法,将刀体区域和其工作背景区域分割出来,使刀具磨损区域更加清晰,提高磨损区域的可识别性;最后,通过Roberts边缘检测确定刀具切削磨损边缘,并使用Zernike正交矩确定刀具切削磨损边缘的精确值以获取磨损区域,提取其磨损信息实现机械刀具切削磨损的检测。实验结果表明:所提方法具有较高图像处理能力以及磨损检测精度。 展开更多
关键词 图像增强 Fisher准则函数 图像阈值分割 Roberts边缘检测 Zernike正交矩 磨损检测
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The Fatigue Fracture Criterion Based on the Latent Energy Approach 被引量:1
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作者 Alexander R. Arutyunyan Robert A. Arutyunyan 《Engineering(科研)》 2010年第5期318-321,共4页
The extensive literature on the fatigue problem, published for more than one hundred years, is reviewed by the known scientists [1,2]. As it follows from these investigations, the fundamental amount of failures in eng... The extensive literature on the fatigue problem, published for more than one hundred years, is reviewed by the known scientists [1,2]. As it follows from these investigations, the fundamental amount of failures in engineering practice connected with the fatigue fractures of materials and structure elements. The fatigue problem is complicated one and it is not solved yet. So the theoretical and experimental investigations of this problem will be continued. In our paper the energy approach to formulate the fatigue strength criterion is proposed. The criterion is based on the conception of the latent energy [3-7]. This conception was not applied previously to the fatigue problem. The latent energy is consumed to generate the irreversible deformation and to damage and fracture of metallic materials. So the fatigue fracture criterion can be formulated using the results of latent energy measurements in the macro experiments. This is most impotent advantage of the proposed approach. The logistic function is used to describe the dependence of latent energy from the value of irreversible deformation. It is assumed that the cyclic strength of metals is defined by the latent energy, stored in specimen, when it is reached the critical value in accordance with the logistic curve in a saturation zone. This proposal is used to formulate the fatigue strength criterion. The functions and parameters of received criterion are concretized and comparisons with experimental results for axial cyclic tension for sheet aluminum alloy specimens are given. 展开更多
关键词 Fatigue FRACTURE criterion ENERGY Approach LATENT ENERGY Heat ENERGY LOGISTICS function Damage PARAMETER
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High-Order Bit Independence Criterion Test for the S-boxes
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作者 GAO Sheng MA Wenping ZHU Jiwei 《Wuhan University Journal of Natural Sciences》 CAS 2011年第5期447-451,共5页
A new security test for the substitution boxes (S-boxes) high-order bit independence criterion (HOBIC) test, is presented. Different from the previous security tests for S-boxes, the HOBIC test can be used to meas... A new security test for the substitution boxes (S-boxes) high-order bit independence criterion (HOBIC) test, is presented. Different from the previous security tests for S-boxes, the HOBIC test can be used to measure the strength of an S-box against attacks that keep some of its input bits constant. Test results over the S-boxes of Data Encryption Standard (DES) and Advanced Encryption Standard (AES) are given and some possible applications of the HOBIC test are analyzed. Meanwhile, the source code for a basic version of the HOBIC test is also provided, the implement process of which shows that it is very fast and efficient for practical applications . 展开更多
关键词 CRYPTOGRAPHY Boolean functions S-boxes highorder bit independence criterion (HOBIC) security test
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