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Masseter Vestibular Evoked Myogenic Potentials in Individuals with definite Meniere’s Disease:An Exploratory Study
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作者 Saloni Gugle Anuj Kumar Neupane 《Journal of Otology》 2025年第3期149-156,共8页
Background:The masseter vestibular evoked myogenic potential(mVEMP) is a novel test that has been explored in various brainstem lesions. However, it has not yet been studied in individuals with definite Meniere's ... Background:The masseter vestibular evoked myogenic potential(mVEMP) is a novel test that has been explored in various brainstem lesions. However, it has not yet been studied in individuals with definite Meniere's disease. Therefore, the current study aimed to investigate m VEMP responses in individuals with definite Meniere's disease and compare them with those of a reference group.Method:The present study investigated narrowband Claus Elberling chirp-evoked m VEMP responses in 22 ears diagnosed with definite Meniere's disease and 22 ears with hearing sensitivity ≤ 15 dB HL across three stimulation frequencies.Results:m VEMP responses in participants with definite Meniere's disease varied from normal to reduced or absent across three octave frequencies. These individuals exhibited significantly reduced P11-N21 peak-to-peak amplitudes compared to those in the reference group. Although a frequency tuning shift toward 1000 Hz was observed, the inter-frequency amplitude ratio of m VEMP was not found to be a sensitive parameter for detecting individuals with definite Meniere's disease. Additionally, no association was found between the degree of hearing loss or the duration of the disease and m VEMP responses. Conclusion: Participants with definite Meniere's disease exhibited reduced P11-N21 amplitude and a tuning shift toward 1000 Hz. These findings suggest the involvement of the vestibulo-trigeminal reflex pathway in this condition. 展开更多
关键词 mVEMP definite Meniere's disease NB CE-chirp frequency tuning AMPLITUDE
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The Necessary and Sufficient Conditions for Two Kinds of Matrix Equtions Having Semipositive Subdefinite Solutions 被引量:1
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作者 何楚宁 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期62-68,共7页
Finding solutions of matrix equations in given set SR n×n is an active research field. Lots of investigation have done for these cases, where S are the sets of general or symmetric matrices and symmetric posit... Finding solutions of matrix equations in given set SR n×n is an active research field. Lots of investigation have done for these cases, where S are the sets of general or symmetric matrices and symmetric positive definite or sysmmetric semiposite definite matrices respectively . Recently, however, attentions are been paying to the situation for S to be the set of general(semi) positive definite matrices(called as semipositive subdefinite matrices below) . In this paper the necessary and sufficient conditions for the following two kinds of matrix equations having semipositive, subdefinite solutions are obtained. General solutions and symmetric solutions of the equations (Ⅰ) and (Ⅱ) have been considered in in detail. 展开更多
关键词 semipositive subdefinite symmetric semipositie definite generalized singualr value decomposition
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POSITIVE DEFINITE KERNEL IN SUPPORT VECTOR MACHINE(SVM) 被引量:3
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作者 谢志鹏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第2期114-121,共8页
The relationship among Mercer kernel, reproducing kernel and positive definite kernel in support vector machine (SVM) is proved and their roles in SVM are discussed. The quadratic form of the kernel matrix is used t... The relationship among Mercer kernel, reproducing kernel and positive definite kernel in support vector machine (SVM) is proved and their roles in SVM are discussed. The quadratic form of the kernel matrix is used to confirm the positive definiteness and their construction. Based on the Bochner theorem, some translation invariant kernels are checked in their Fourier domain. Some rotation invariant radial kernels are inspected according to the Schoenberg theorem. Finally, the construction of discrete scaling and wavelet kernels, the kernel selection and the kernel parameter learning are discussed. 展开更多
关键词 support vector machines(SVMs) mercer kernel reproducing kernel positive definite kernel scaling and wavelet kernel
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SYMMETRIC POSITIVE DEFINITE SOLUTIONS OF MATRIX EQUATIONS (AX,XB)=(C,D) AND AXB=C 被引量:2
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作者 戴华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期56+52-55,共5页
The symmetric positive definite solutions of matrix equations (AX,XB)=(C,D) and AXB=C are considered in this paper. Necessary and sufficient conditions for the matrix equations to have symmetric positive de... The symmetric positive definite solutions of matrix equations (AX,XB)=(C,D) and AXB=C are considered in this paper. Necessary and sufficient conditions for the matrix equations to have symmetric positive definite solutions are derived using the singular value and the generalized singular value decompositions. The expressions for the general symmetric positive definite solutions are given when certain conditions hold. 展开更多
关键词 numerical algebra MATRIX EQUATION symmetric positive definite solution
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A Remark on the Positive Definite Problem of a Binary Quartic Form 被引量:4
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作者 凌生智 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第1期43-46, ,共4页
In this paper,we discussed the positive definite problem of binary quartic forms and obtained a necessary and sufficient conditions.
关键词 positive definite binary quartic form negative definite
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The Classification of Positive Definite Unimodular Lattices Over Z[(1+21^(1/2))/2]
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作者 王瑞卿 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期87-93,共7页
In this paper, the author applies adjacent lattice method and Siegel mass formula to determine the classes of positive definite unimodular lattices of rank 4 over Z , and obtains that the class number of unit genus ... In this paper, the author applies adjacent lattice method and Siegel mass formula to determine the classes of positive definite unimodular lattices of rank 4 over Z , and obtains that the class number of unit genus gen( I 4 ) is nine and the class number of even unimodular lattices is three, and also gives the representative lattices of each class. 展开更多
关键词 positive definite unimodular adjacent lattice class number Siegel mass formula orthogonal group
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Completely Positive Definite Maps Over Topological-algebras
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作者 许天周 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第4期73-77, ,共5页
In this paper, we discuss completely positive definite maps over topological algebras. A Schwarz type inequality for n-positive definite maps, and the Stinespring representation theorem for completely positive definit... In this paper, we discuss completely positive definite maps over topological algebras. A Schwarz type inequality for n-positive definite maps, and the Stinespring representation theorem for completely positive definite maps over topological algebras are given. 展开更多
关键词 topological algebra n-positive definite maps completely positive definite map schwarz type inequality Stinespring representation theorem
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The Classification of Positive Definite Unimodular Lattices Over Z[(1+211/2)/2] 被引量:4
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作者 王瑞卿 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期87-93,共页
In this paper, the author applies adjacent lattice method and Siegel mass formula to determine the classes of positive definite unimodular lattices of rank 4 over Z , and obtains that the class number of unit genus ... In this paper, the author applies adjacent lattice method and Siegel mass formula to determine the classes of positive definite unimodular lattices of rank 4 over Z , and obtains that the class number of unit genus gen( I 4 ) is nine and the class number of even unimodular lattices is three, and also gives the representative lattices of each class. 展开更多
关键词 positive definite unimodular adjacent lattice class number Siegel mass formula orthogonal group
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Study on the Relation of Definite Integral and Indefinite Integral
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作者 SUN Bao-fa 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第4期523-528,共6页
Relation of definite integral and indefinite integral was discussed and an important result was gotten. If f(x) is bounded and has primary function, the formal definite integral x s f(t)dt is the indefinite integral o... Relation of definite integral and indefinite integral was discussed and an important result was gotten. If f(x) is bounded and has primary function, the formal definite integral x s f(t)dt is the indefinite integral of f(x), where x is a self-variable, s is a parameter,~f(x) is a function defined in(-∞, +∞), which comes from f(x) by restriction and extension. In other words, the indefinite integral is a special form of definite integral, its lower integral limit and upper integral limit are all indefinite. 展开更多
关键词 definite integral indefinite integral primary function
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The Metapositive Definite Self-Conjugate Solution of the Matrix Equation AXB=C over a Skew Field 被引量:3
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作者 王卿文 《Chinese Quarterly Journal of Mathematics》 CSCD 1995年第3期42-51,共10页
Let F be the strong p-division ring [4]. This paper is sequel to [1]. Metapositive definite self-conjugate matrix over F is defined and the necessary and sufficient conditions for determining whether a partitioned mat... Let F be the strong p-division ring [4]. This paper is sequel to [1]. Metapositive definite self-conjugate matrix over F is defined and the necessary and sufficient conditions for determining whether a partitioned matrix over F is metapositive definite self-conjugate are given.Moreover,a decomposition of pairwise matrices over F with the same numbers of columns is also presented. Whence some necessary and sufficient conditions for the existence of and the explicit expression for the metapositive definite self-conjugate solution of the matrix equation AXB=C over F are derived. 展开更多
关键词 the strong p-division ring matrix equation metapositive definite self-coniugate matrix
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Some new bound estimates of the Hermitian positive definite solutions of the nonlinear matrix equation X^s+ A~*X^(-t) A = Q 被引量:1
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作者 Cai Jing Chen Jianlong 《Journal of Southeast University(English Edition)》 EI CAS 2019年第1期142-146,共5页
The range and existence conditions of the Hermitian positive definite solutions of nonlinear matrix equations Xs+A*X-tA=Q are studied, where A is an n×n non-singular complex matrix and Q is an n×n Hermitian ... The range and existence conditions of the Hermitian positive definite solutions of nonlinear matrix equations Xs+A*X-tA=Q are studied, where A is an n×n non-singular complex matrix and Q is an n×n Hermitian positive definite matrix and parameters s,t>0. Based on the matrix geometry theory, relevant matrix inequality and linear algebra technology, according to the different value ranges of the parameters s,t, the existence intervals of the Hermitian positive definite solution and the necessary conditions for equation solvability are presented, respectively. Comparing the existing correlation results, the proposed upper and lower bounds of the Hermitian positive definite solution are more accurate and applicable. 展开更多
关键词 nonlinear matrix equation Hermitian positive definite solution solution bound matrix inequality
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On the Hermitian Positive Definite Solutions of the Nonlinear Matrix Equation X^s-A~*X^(-t)A=Q with Perturbation Estimates 被引量:1
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作者 Jing CAI 《Journal of Mathematical Research with Applications》 CSCD 2013年第6期673-682,共10页
In this paper, the Hermitian positive definite solutions of the nonlinear matrix equation X^s - A^*X^-tA = Q are studied, where Q is a Hermitian positive definite matrix, s and t are positive integers. The existence ... In this paper, the Hermitian positive definite solutions of the nonlinear matrix equation X^s - A^*X^-tA = Q are studied, where Q is a Hermitian positive definite matrix, s and t are positive integers. The existence of a Hermitian positive definite solution is proved. A sufficient condition for the equation to have a unique Hermitian positive definite solution is given. Some estimates of the Hermitian positive definite solutions are obtained. Moreover, two perturbation bounds for the Hermitian positive definite solutions are derived and the results are illustrated by some numerical examples. 展开更多
关键词 matrix equation Hermitian positive definite solution PROPERTY EXISTENCE perturbation bound.
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Two Structure-Preserving-Doubling Like Algorithms to Solve the Positive Definite Solution of the Equation X-A^(H)X^(-1)A=Q 被引量:1
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作者 Xiao-Xia Guo Hong-Xiao Wu 《Communications on Applied Mathematics and Computation》 2021年第1期123-135,共13页
In this paper,we study the nonlinear matrix equation X-A^(H)X^(-1)A=Q,where A,Q∈C^(n×n),Q is a Hermitian positive definite matrix and X∈C^(n×n)is an unknown matrix.We prove that the equation always has a u... In this paper,we study the nonlinear matrix equation X-A^(H)X^(-1)A=Q,where A,Q∈C^(n×n),Q is a Hermitian positive definite matrix and X∈C^(n×n)is an unknown matrix.We prove that the equation always has a unique Hermitian positive definite solution.We present two structure-preserving-doubling like algorithms to find the Hermitian positive definite solution of the equation,and the convergence theories are established.Finally,we show the effectiveness of the algorithms by numerical experiments. 展开更多
关键词 Positive definite solution Structure-preserving-doubling like algorithm CONVERGENCE Numerical experiment
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DIAGONALLY COMPENSATED REDUCTION AND MULTISPLITTING OF A SYMMETRIC POSITIVE DEFINITE MATRIX
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作者 刘仲云 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第1期61-70,共10页
To solve the symmetric positive definite linear system Ax = b on parallel and vector machines, multisplitting methods are considered. Here the s.p.d. (symmetric positive definite) matrix A need not be assumed in a spe... To solve the symmetric positive definite linear system Ax = b on parallel and vector machines, multisplitting methods are considered. Here the s.p.d. (symmetric positive definite) matrix A need not be assumed in a special form (e.g. the dissection form [11]). The main tool for deriving our methods is the diagonally compensated reduction (cf. [1]). The convergence of such methods is also discussed by using this tool. [WT5,5”HZ] 展开更多
关键词 MULTISPLITTING DIAGONAL compensated REDUCTION SYMMETRIC POSITIVE definite.
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SEMI-DEFINITE RELAXATION ALGORITHM OF MULTIPLE KNAPSACK PROBLEM
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作者 Chen Feng Yao EnyuDept.ofMath.,ZhejiangUniv.,Hangzhou310027,China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第2期241-250,共10页
The multiple knapsack problem denoted by MKP (B,S,m,n) can be defined as fol- lows.A set B of n items and a set Sof m knapsacks are given such thateach item j has a profit pjand weightwj,and each knapsack i has a ca... The multiple knapsack problem denoted by MKP (B,S,m,n) can be defined as fol- lows.A set B of n items and a set Sof m knapsacks are given such thateach item j has a profit pjand weightwj,and each knapsack i has a capacity Ci.The goal is to find a subset of items of maximum profit such that they have a feasible packing in the knapsacks.MKP(B,S,m,n) is strongly NP- Complete and no polynomial- time approximation algorithm can have an approxima- tion ratio better than0 .5 .In the last ten years,semi- definite programming has been empolyed to solve some combinatorial problems successfully.This paper firstly presents a semi- definite re- laxation algorithm (MKPS) for MKP (B,S,m,n) .It is proved that MKPS have a approxima- tion ratio better than 0 .5 for a subclass of MKP (B,S,m,n) with n≤ 1 0 0 ,m≤ 5 and maxnj=1{ wj} minmi=1{ Ci} ≤ 2 3 . 展开更多
关键词 multiple knapsack problem semi- definite relaxation approximation algorithm combina- torial optimization.
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Thermal Sense Prediction Model for Definite Human Group in Indoor Case
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作者 张春程 陈祥光 徐远清 《Journal of Beijing Institute of Technology》 EI CAS 2010年第2期232-236,共5页
In order to build a prediction model of the indoor thermal comfort for a given human group, the original predicted mean vote (PMV) equation is reconstructed and simplified, the modified PMV equation is named PMVR (... In order to build a prediction model of the indoor thermal comfort for a given human group, the original predicted mean vote (PMV) equation is reconstructed and simplified, the modified PMV equation is named PMVR (PMV for region) , where five variables are needed to be fitted with the dataset of actual thermal sense of a definite human group. As the fitting algorithm, the particle swarm optimization algorithm is used to optimize the solution, and a fixed PMVR can be finally determined. Experiment results indicate that for a definite human group, PMVR is more accurate on the prediction of thermal sense compared with some other models. 展开更多
关键词 thermal comfort definite human group PMV PMVR
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Comparison of Different Approaches of Finding the Positive Definite Metric in Pseudo-Hermitian Theories
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作者 Ananya Ghatak Bhabani Prasad Mandal 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第5期533-539,共7页
To develop a unitary quantum theory with probabilistic description for pseudo-Hermitian systems one needs to consider the theories in a different Hilbert space endowed with a positive definite metric operator. There a... To develop a unitary quantum theory with probabilistic description for pseudo-Hermitian systems one needs to consider the theories in a different Hilbert space endowed with a positive definite metric operator. There are different approaches to find such metric operators. We compare the different approaches of calculating positive definite metric operators in pseudo-Hermitian theories with the help of several explicit examples in non-relativistic as well as in relativistic situations. Exceptional points and spontaneous symmetry breaking are also discussed in these models. 展开更多
关键词 pseudo-Hermitian quantum theory positive definite metric operator relativistic non-Hermitian system P T symmetry quantum mechanics modified Hilbert space
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ON RUBIN'S HARMONIC ANALYSIS AND ITS RELATED POSITIVE DEFINITE FUNCTIONS
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作者 Nji Bettaibi Kamel Mezlini Moufida El Gunichi 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期1851-1874,共24页
In this paper,a new formulation of the Rubin’s q-translation is given,which leads to a reliable q-harmonic analysis.Next,related q-positive definite functions are introduced and studied,and a Bochner’s theorem is pr... In this paper,a new formulation of the Rubin’s q-translation is given,which leads to a reliable q-harmonic analysis.Next,related q-positive definite functions are introduced and studied,and a Bochner’s theorem is proved. 展开更多
关键词 q-harmonic analysis definite positive function Bochner theorem
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THE PARALLEL MULTISPLITTING METHOD FOR CONSISTENT SYMMETRIC POSITIVE(SEMI-)DEFINITE SYSTEMS
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作者 Liu Zhongyun (dept.of Math.,Shanghai Univrsity,Shanghai 200436,PRC)Yinyueli(Light Industry Higher Training School,Changsha 410015,PRC)Li Renfa(Dept.of Comput.Sci.,Hunan University,Changsha 410082,PRC) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第S1期120-121,共2页
Main resultsTheorem 1 Let A be an n×n symmetric positive semidefinite matrix and let
关键词 SEMI definite SYSTEMS THE PARALLEL MULTISPLITTING METHOD FOR CONSISTENT SYMMETRIC POSITIVE
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Some Notes on the Positive Definite Problem of a Binary Quartic Form
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作者 CHEN Bao-xing (Department of Mathematics, Zhangzhou Teacher’s College, Zhangzhou 363000, China) 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第1期68-73,共6页
In this paper, we discuss the positive definite problem of a binary quartic form and obtain a necessary and sufficient condition. In addition we give two examples to show that there are some errors in the paper [1].
关键词 positive definite binary quartic form quartic equation
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