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Study on Microsatellite Distribution in Complete Genomes of Tobacco Vein Clearing Virus 被引量:7
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作者 杨纪青 《Agricultural Science & Technology》 CAS 2010年第7期132-135,共4页
MATLAB software and optimal complete subgraph algorithm were used to extract and reveal the microsatellite distribution features in the complete genomes of the tobacco vein clearing virus (NC-003 378.1) from the NCB... MATLAB software and optimal complete subgraph algorithm were used to extract and reveal the microsatellite distribution features in the complete genomes of the tobacco vein clearing virus (NC-003 378.1) from the NCBI database.The results showed that the repetitions number and their location of the N-base group has been extracted and displayed.The largest repetitions of N-base group in the complete genomes of the tobacco vein clearing virus was decreased as the exponential function with the increasing of N.The method used in this study could be applied to the extraction and revealing of the microsatellite distribution features in the complete genomes of other viruses,thereby provided a basis for the research of the structure and the law of function,inheritance and variation by the using of the microsatellite distribution features. 展开更多
关键词 Tobacco vein clearing virus Complete genomes Microsatellite distribution Means of genetic algorithms Optimal complete subgraph algorithm
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A VIDEO SPECTRUM SPLITTING ENCODING SCHEME BASED ON HUMAN VISION AND ITS COMPUTER SIMULATION
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作者 赵宇 李华 +1 位作者 俞斯乐 滕建辅 《Transactions of Tianjin University》 EI CAS 1995年第1期79+76-79,共5页
In this paper, a 3-D video encoding scheme suitable for digital TV/HDTV (high definition television) is studied through computer simulation. The encoding scheme is designed to provide a good match to human vision. Bas... In this paper, a 3-D video encoding scheme suitable for digital TV/HDTV (high definition television) is studied through computer simulation. The encoding scheme is designed to provide a good match to human vision. Basically, this involves transmission of low frequency luminance information at full frame rate for good motion rendition and transmission of high frequency luminance signal at reduced frame rate for good detail in static images. 展开更多
关键词 D video encoding discrete wavelet transform human vision computer simulation
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COMBINING FEATURE SCALING ESTIMATION WITH SVM CLASSIFIER DESIGN USING GA APPROACH 被引量:2
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作者 Yu Ying Wang Xiaolong Liu Bingquan 《Journal of Electronics(China)》 2005年第5期550-557,共8页
This letter adopts a GA (Genetic Algorithm) approach to assist in learning scaling of features that are most favorable to SVM (Support Vector Machines) classifier, which is named as GA-SVM. The relevant coefficients o... This letter adopts a GA (Genetic Algorithm) approach to assist in learning scaling of features that are most favorable to SVM (Support Vector Machines) classifier, which is named as GA-SVM. The relevant coefficients of various features to the classification task, measured by real-valued scaling, are estimated efficiently by using GA. And GA exploits heavy-bias operator to promote sparsity in the scaling of features. There are many potential benefits of this method:Feature selection is performed by eliminating irrelevant features whose scaling is zero, an SVM classifier that has enhanced generalization ability can be learned simultaneously. Experimental comparisons using original SVM and GA-SVM demonstrate both economical feature selection and excellent classification accuracy on junk e-mail recognition problem and Internet ad recognition problem. The experimental results show that comparing with original SVM classifier, the number of support vector decreases significantly and better classification results are achieved based on GA-SVM. It also demonstrates that GA can provide a simple, general, and powerful framework for tuning parameters in optimal problem, which directly improves the recognition performance and recognition rate of SVM. 展开更多
关键词 Support Vector Machines (SVM) Genetic Algorithm (GA) Feature scaling Feature selection Zero-bias operator
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DFT calculation on relaxation and electronic structure of sulfide minerals surfaces in presence of H_2O molecule 被引量:4
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作者 陈建华 龙贤灏 +2 位作者 赵翠华 康端 郭进 《Journal of Central South University》 SCIE EI CAS 2014年第10期3945-3954,共10页
First-principles calculations are performed to investigate the relaxation and electronic properties of sulfide minerals surfaces(MoS2, Sb2S3, Cu2 S, ZnS, PbS and FeS2) in presence of H2 O molecule. The calculated resu... First-principles calculations are performed to investigate the relaxation and electronic properties of sulfide minerals surfaces(MoS2, Sb2S3, Cu2 S, ZnS, PbS and FeS2) in presence of H2 O molecule. The calculated results show that the structure and electronic properties of sulfide minerals surfaces have been influenced in presence of H2 O molecule. The adsorption of the flotation reagent at the interface of mineral-water would be different from that of mineral surface due to the changes of surface structures and electronic properties caused by H2 O molecule. Hence, the influence of H2 O molecule on the reaction of flotation reagent with sulfide mineral surface will attract more attention. 展开更多
关键词 sulfide minerals surfaces H_2O molecule RELAXATION electronic properties density-functional theory(DFT) calculation
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New Operator Identities and Combinatorics Studied by Virtue of IWOP Technique
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作者 FAN Hong-Yi OU-YANG Jing JIANG Zhong-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期49-54,共6页
Using the coherent state representation we derive some new operator identities and study some mathematical relations in comblnatorics. The technique of integral within an ordered product (IWOP) of operators plays an... Using the coherent state representation we derive some new operator identities and study some mathematical relations in comblnatorics. The technique of integral within an ordered product (IWOP) of operators plays an essential role in realizing our goal. 展开更多
关键词 IWOP technique COMBINATORICS operator identities
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Expanded Relative Operator Entropies and Operator Valued α-Divergence
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作者 Hiroshi Isa Masatoshi Ito +2 位作者 Eizaburo Kamei Hiroaki Tohyama MasayukiWatanabe 《Journal of Mathematics and System Science》 2015年第6期215-224,共10页
For strictly positive operators A and B, and for x ∈ [0,1] and r ∈[-1,1], we investigate the operator power mean A#x,rB=A1/2{(1-x)/+x(a-1*2BA-1/2)r}1/rA1/2 If r = O, this is reduced to the geometric operator m... For strictly positive operators A and B, and for x ∈ [0,1] and r ∈[-1,1], we investigate the operator power mean A#x,rB=A1/2{(1-x)/+x(a-1*2BA-1/2)r}1/rA1/2 If r = O, this is reduced to the geometric operator mean A#x,rB=A1/2{(1-x)/+x(a-1*2BA-1/2)r}1/rA1/2 Since A #0,r B = A and A #l,r B = B, weregard A#t,rB as apath combining A and B.Our aim is to show the essential properties of St,r (AIB). The Tsallis relative operator entropy by Yanagi, Kuriyama and Furuichi can also be expanded, and by using this, we can give an expanded operator valued a-divergence and obtain its properties. 展开更多
关键词 Operator power mean relative operator entropy Tsallis relative operator entropy operator valued a-divergence
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New learning subspace method for image feature extraction
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作者 CAO Jian-hai LI Long LU Chang-hou 《Optoelectronics Letters》 EI 2006年第6期471-473,共3页
A new method of Windows Minimum/Maximum Module Learning Subspace Algorithm(WMMLSA) for image feature extraction is presented.The WMMLSM is insensitive to the order of the training samples and can regulate effectively ... A new method of Windows Minimum/Maximum Module Learning Subspace Algorithm(WMMLSA) for image feature extraction is presented.The WMMLSM is insensitive to the order of the training samples and can regulate effectively the radical vectors of an image feature subspace through selecting the study samples for subspace iterative learning algorithm,so it can improve the robustness and generalization capacity of a pattern subspace and enhance the recognition rate of a classifier.At the same time,a pattern subspace is built by the PCA method.The classifier based on WMMLSM is successfully applied to recognize the pressed characters on the gray-scale images.The results indicate that the correct recognition rate on WMMLSM is higher than that on Average Learning Subspace Method,and that the training speed and the classification speed are both improved.The new method is more applicable and efficient. 展开更多
关键词 图像特征提取 子空间算法 鲁棒性 分类器
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q-Deforrned Entangled States Representations and Some Applications
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作者 许业军 宋军 +1 位作者 袁洪春 刘秋宇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第2期227-231,共5页
The q-deformed entangled states are introduced by using deformation quantization methods and new normal ordering of the vacuum projection operator for q-deformed boson oscillator. In similar way, by virtue of the tech... The q-deformed entangled states are introduced by using deformation quantization methods and new normal ordering of the vacuum projection operator for q-deformed boson oscillator. In similar way, by virtue of the technique of integration within an ordered product (IWOP) of operators, the new completeness and orthogonMity relations composed of the bra and ket, which are not mutually Hermitian conjugates are obtained. Furthermore, the property of squeezing operator represented by the q-deformed entangled states is exhibited. Lastly, the nonclassical properties of the q-deformed two-mode squeezed vacuum state are studied. 展开更多
关键词 q-deformed entangled state completeness and orthogonality relations nonclassical properties
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Magnetic Properties of Ferromagnetic Double Layers with Ferrimagnetic Interlayer Coupling at Zero Temperature
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作者 JIANG Wei ZHU Cheng-Bo WANG Wei ZHANG Fan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期349-352,共4页
Spin-wave theory is used to study magnetic properties of ferromagnetic double layers with a ferrimagnetic interlayer coupling at zero temperature. The spin-wave spectra and four sublattices magnetizations and internal... Spin-wave theory is used to study magnetic properties of ferromagnetic double layers with a ferrimagnetic interlayer coupling at zero temperature. The spin-wave spectra and four sublattices magnetizations and internal energy are calculated by employing retarded Green function technique. The sublattice magnetizations at ground state are smaller than their classical values, owing to the zero-point quantum fluctuations of the spins. 展开更多
关键词 spin-wave theory ferromagnetic double layers zero-point quantum fluctuation ferrimagnetic interlay coupling
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Various characterizations of product Hardy spaces associated to Schrdinger operators 被引量:3
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作者 LIU SuYing ZHAO Kai 《Science China Mathematics》 SCIE CSCD 2015年第12期2549-2564,共16页
For every i = 1, 2, we let Li =-?ni+ Vi be a Schr¨odinger operator on Rni in which Vi∈ L1loc(Rni)is a non-negative function on Rni. We obtain some characterizations for functions in the product Hardy space H1L1,... For every i = 1, 2, we let Li =-?ni+ Vi be a Schr¨odinger operator on Rni in which Vi∈ L1loc(Rni)is a non-negative function on Rni. We obtain some characterizations for functions in the product Hardy space H1L1,L2(Rn1 × Rn2) associated to L1 and L2 by using different norms on distinct variables. 展开更多
关键词 product Hardy space Schr¨odinger operator non-tangential maximal and quadratic function SEMIGROUP product atom
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Symmetry of the Point Spectrum of Upper Triangular Infinite Dimensional Hamiltonian Operators 被引量:2
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作者 WANG Hua Alatancang HUANG dun die 《Journal of Mathematical Research and Exposition》 CSCD 2009年第5期907-912,共6页
In this paper, by using characterization of the point spectrum of the upper triangular infinite dimensional Hamiltonian operator H, a necessary and sufficient condition is obtained on the symmetry of σP(A) and σ1/... In this paper, by using characterization of the point spectrum of the upper triangular infinite dimensional Hamiltonian operator H, a necessary and sufficient condition is obtained on the symmetry of σP(A) and σ1/P(-A^*) with respect to the imaginary axis. Then the symmetry of the point spectrum of H is given, and several examples are presented to illustrate the results. 展开更多
关键词 non-self-adjoint operator infinite dimensional Hamiltonian operator point spectrum symmetry.
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A system of matrix equations and its applications 被引量:4
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作者 WANG QingWen HE ZhuoHeng 《Science China Mathematics》 SCIE 2013年第9期1795-1820,共26页
We derive the solvability conditions and an expression of the general solution to the system of matrix equations A 1X=C1 , A2Y=C2 , YB2=D2 , Y=Y*, A3Z=C3 , ZB3=D3 , Z=Z*, B4X+(B4X)+C4YC4*+D4ZD4*=A4 . Moreover, we inve... We derive the solvability conditions and an expression of the general solution to the system of matrix equations A 1X=C1 , A2Y=C2 , YB2=D2 , Y=Y*, A3Z=C3 , ZB3=D3 , Z=Z*, B4X+(B4X)+C4YC4*+D4ZD4*=A4 . Moreover, we investigate the maximal and minimal ranks and inertias of Y and Z in the above system of matrix equations. As a special case of the results, we solve the problem proposed in Farid, Moslehian, Wang and Wu's recent paper (Farid F O, Moslehian M S, Wang Q W, et al. On the Hermitian solutions to a system of adjointable operator equations. Linear Algebra Appl, 2012, 437: 1854-1891). 展开更多
关键词 linear matrix equation Moore-Penrose inverse RANK INERTIA
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Additional symmetries of constrained CKP and BKP hierarchies 被引量:4
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作者 TIAN KeLei HE JingSong +1 位作者 CHENG JiPeng CHENG Yi 《Science China Mathematics》 SCIE 2011年第2期257-268,共12页
The additional symmetries of the constrained CKP (cCKP) and BKP (cBKP) hierarchies are given by their actions on the Lax operators, and their actions on the eigenfunction and adjoint eigenfunction {Φ i , Ψ i } are p... The additional symmetries of the constrained CKP (cCKP) and BKP (cBKP) hierarchies are given by their actions on the Lax operators, and their actions on the eigenfunction and adjoint eigenfunction {Φ i , Ψ i } are presented explicitly. Furthermore, we show that acting on the space of the wave operator, *k forms new centerless W cC 1+∞ and W cB 1+∞ -subalgebra of centerless W 1+∞ respectively. In order to define above symmetry flows *k of the cCKP and cBKP hierarchies, two vital operators Y k are introduced to revise the additional symmetry flows of the CKP and BKP hierarchies. 展开更多
关键词 constrained CKP hierarchy constrained BKP hierarchy additional symmetry
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Toeplitz operators on H^2(iR)
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作者 XIE PeiZhu CAO GuangFu 《Science China Mathematics》 SCIE 2011年第9期1995-2004,共10页
In this paper,the essential spectra of Toeplitz operators is discussed,and the K-theory of the Toeplitz algebra generated by {Tφ|φ∈C(iR)} is computed.In addition,the characteristic equation of Toeplitz operators is... In this paper,the essential spectra of Toeplitz operators is discussed,and the K-theory of the Toeplitz algebra generated by {Tφ|φ∈C(iR)} is computed.In addition,the characteristic equation of Toeplitz operators is obtained and the algebraic properties of Toeplitz operators are discussed. 展开更多
关键词 Toeplitz operator Hardy space Fredholm theory
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CPT-Frames for Non-Hermitian Hamiltonians 被引量:2
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作者 曹怀信 郭志华 陈峥立 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第9期328-334,共7页
Based on the PT-symmetric quantum theory, the concepts of PT-frame, PT-symmetric operator and CPT-frame on a Hilbert space K and for an operator on K are proposed. It is proved that the spectrum and point spectrum of ... Based on the PT-symmetric quantum theory, the concepts of PT-frame, PT-symmetric operator and CPT-frame on a Hilbert space K and for an operator on K are proposed. It is proved that the spectrum and point spectrum of a PT-symmetric linear operator are both symmetric with respect to the real axis and the eigenvalues of an unbroken PT-symmetric operator are real. For a linear operator H on Cd, it is proved that H has unbroken PT- symmetry if and only if it has d different eigenvalues and the corresponding eigenstates are eigenstates of PT. Given a CPT-frame on K, a new positive inner product on K is induced and called CPT-inner product. Te relationship between the CPT-adjoint and the Dirac adjoint of a densely defined linear operator is derived, and it is proved that an operator which has a bounded CPT-frame is CPT-Hermitian if and only if it is T-symmetric, in that case, it is similar to a Hermitian operator. The existence of an operator C consisting of a CPT-frame is discussed, These concepts and results will serve a mathematical discussion about PT-symmetric quantum mechanics. 展开更多
关键词 CPT-frame PT-frame PT-SYMMETRY OPERATOR
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GUS-property for Lorentz cone linear complementarity problems on Hilbert spaces 被引量:3
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作者 MIAO XinHe HUANG ZhengHai 《Science China Mathematics》 SCIE 2011年第6期1259-1268,共10页
Given a real(finite-dimensional or infinite-dimensional) Hilbert space H with a Jordan product,we consider the Lorentz cone linear complementarity problem,denoted by LCP(T,Ω,q),where T is a continuous linear operator... Given a real(finite-dimensional or infinite-dimensional) Hilbert space H with a Jordan product,we consider the Lorentz cone linear complementarity problem,denoted by LCP(T,Ω,q),where T is a continuous linear operator on H,ΩH is a Lorentz cone,and q ∈ H.We investigate some conditions for which the problem concerned has a unique solution for all q ∈ H(i.e.,T has the GUS-property).Several sufficient conditions and several necessary conditions are given.In particular,we provide two suficient and necessary conditions of T having the GUS-property.Our approach is based on properties of the Jordan product and the technique from functional analysis,which is different from the pioneer works given by Gowda and Sznajder(2007) in the case of finite-dimensional spaces. 展开更多
关键词 Lorentz cone linear complementarity problem Jordan product Lorentz cone
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Dolphin swarm algorithm 被引量:9
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作者 Tian-qi WU Min YAO Jian-hua YANG 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第8期717-729,共13页
By adopting the distributed problem-solving strategy, swarm intelligence algorithms have been successfully applied to many optimization problems that are difficult to deal with using traditional methods. At present, t... By adopting the distributed problem-solving strategy, swarm intelligence algorithms have been successfully applied to many optimization problems that are difficult to deal with using traditional methods. At present, there are many well-implemented algorithms, such as particle swarm optimization, genetic algorithm, artificial bee colony algorithm, and ant colony optimization. These algorithms have already shown favorable performances. However, with the objects becoming increasingly complex, it is becoming gradually more difficult for these algorithms to meet human's demand in terms of accuracy and time. Designing a new algorithm to seek better solutions for optimization problems is becoming increasingly essential. Dolphins have many noteworthy biological characteristics and living habits such as echolocation, information exchanges, cooperation, and division of labor. Combining these biological characteristics and living habits with swarm intelligence and bringing them into optimization problems, we propose a brand new algorithm named the ‘dolphin swarm algorithm' in this paper. We also provide the definitions of the algorithm and specific descriptions of the four pivotal phases in the algorithm, which are the search phase, call phase, reception phase, and predation phase. Ten benchmark functions with different properties are tested using the dolphin swarm algorithm, particle swarm optimization, genetic algorithm, and artificial bee colony algorithm. The convergence rates and benchmark function results of these four algorithms are compared to testify the effect of the dolphin swarm algorithm. The results show that in most cases, the dolphin swarm algorithm performs better. The dolphin swarm algorithm possesses some great features, such as first-slow-then-fast convergence, periodic convergence, local-optimum-free, and no specific demand on benchmark functions. Moreover, the dolphin swarm algorithm is particularly appropriate to optimization problems, with more calls of fitness functions and fewer individuals. 展开更多
关键词 Swarm intelligence Bio-inspired algorithm DOLPHIN OPTIMIZATION
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LOCAL SPECTRA OF UNILATERAL OPERATOR WEIGHTED SHIFTS
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作者 A.BOURHIM 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2004年第3期369-382,共14页
In this note, the local spectral properties of unilateral operator weighted shifts are studied.
关键词 Operator weighted shifts Local spectrum Single-valued extension property Dunford's condition(C) Bishop's property (β)
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Bilayered semiconductor graphene nanostructures with periodically arranged hexagonal holes
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作者 Dmitry G. Kvashnin Peter Vancso +4 位作者 Liubov Yu. Antipina Geza I. Mark Laszlo P. Biro Pavel B. Sorokin Leonid A. Chernozatonskii 《Nano Research》 SCIE EI CAS CSCD 2015年第4期1250-1258,共9页
We present a theoretical study of new nanostructures based on bilayered graphene with periodically arranged hexagonal holes (bilayered graphene antidots). Our ab initio calculations show that fabrication of hexagona... We present a theoretical study of new nanostructures based on bilayered graphene with periodically arranged hexagonal holes (bilayered graphene antidots). Our ab initio calculations show that fabrication of hexagonal holes in bigraphene leads to connection of the neighboring edges of the two graphene layers with formation of a hollow carbon nanostructure sheet which displays a wide range of electronic properties (from semiconductor to metallic), depending on the size of the holes and the distance between them. The results were additionally supported by wave packet dynamical transport calculations based on the numerical solution of the time-dependent Schr/Sdinger equation. 展开更多
关键词 gaphene ANTIDOTS electronic properties DFT
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Eventual Positivity of Hermitian Polynomials and Integral Operators 被引量:1
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作者 Colin TAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2016年第1期83-94,共12页
Quillen proved that if a Hermitian bihomogeneous polynomial is strictly positive on the unit sphere, then repeated multiplication of the standard sesquilinear form to this polynomial eventually results in a sum of Her... Quillen proved that if a Hermitian bihomogeneous polynomial is strictly positive on the unit sphere, then repeated multiplication of the standard sesquilinear form to this polynomial eventually results in a sum of Hermitian squares. Catlin-D'Angelo and Varolin deduced this positivstellensatz of Quillen from the eventual positive-definiteness of an associated integral operator. Their arguments involve asymptotic expansions of the Bergman kernel. The goal of this article is to give an elementary proof of the positive-definiteness of this integral operator. 展开更多
关键词 ASYMPTOTICS POLYNOMIAL POSITIVITY
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