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On the Triple Sums of Hecke Eigenvalues on Certain Polynomials
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作者 HUA Guodong 《数学进展》 北大核心 2025年第6期1261-1277,共17页
Let f,g and h be three distinct primitive holomorphic cusp forms of even integral weights k_(1),k_(2)and k_(3)for the full modular groupΓ=SL(2,Z),and denote byλ_(f)(n),λ_(g)(n),λ_(h)(n)the corresponding normalized... Let f,g and h be three distinct primitive holomorphic cusp forms of even integral weights k_(1),k_(2)and k_(3)for the full modular groupΓ=SL(2,Z),and denote byλ_(f)(n),λ_(g)(n),λ_(h)(n)the corresponding normalized Fourier coefficients,respectively.In this paper,we investigate the correlations of triple sums associated to these Fourier coefficientsλ_(f)(n),λ_(g)(n),λ_(h)(n)over certain polynomials,and obtain some power-saving asymptotic estimates which beat the trivial bounds. 展开更多
关键词 Hecke eigenvalue triple correlation sum automorphic L-function asymptotic behavior
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New Universal Bounds for Eigenvalues of the Markov Diffusion Operator L2
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作者 Yanli LI Feng DU 《Journal of Mathematical Research with Applications》 2025年第6期745-757,共13页
In this paper,we study the eigenvalue problem of the Markov diffusion operator L^(2),and give generalized inequalities for eigenvalues of the operator L^(2)on a Markov diffusion triple.By applying these inequalities,w... In this paper,we study the eigenvalue problem of the Markov diffusion operator L^(2),and give generalized inequalities for eigenvalues of the operator L^(2)on a Markov diffusion triple.By applying these inequalities,we then get some new universal bounds for eigenvalues of a special Markov diffusion operator L^(2)on bounded domains in an Euclidean space.Moreover,our results can reveal the relationship between the(k+1)-th eigenvalue and the first k eigenvalues in a relatively straightforward manner. 展开更多
关键词 Markov diffusion operator eigenvalues universal bounds Markov diffusion triple
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INEQUALITIES FOR EIGENVALUES OF POLYNOMIAL OPERATOR OF THE DRIFTING LAPLACIAN ON THE CIGAR SOLITON
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作者 YUAN Yuan SUN He-jun 《数学杂志》 2025年第4期293-306,共14页
In this paper,we investigate the weighted Dirichlet eigenvalue problem of polynomial operator of the drifting Laplacian on the cigar soliton■as follows■where is a positive continuous function on,denotes the outward ... In this paper,we investigate the weighted Dirichlet eigenvalue problem of polynomial operator of the drifting Laplacian on the cigar soliton■as follows■where is a positive continuous function on,denotes the outward unit normal to the boundary,and are two nonnegative constants.We establish some universal inequalities for eigenvalues of this problem. 展开更多
关键词 drifting Laplacian Cigarsoliton EIGENVALUE
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大型植物工厂叶菜长势监测方法
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作者 马丽丹 王英龙 +5 位作者 梁海铖 李国龙 李慧文 杨旭 何庆樑 辜松 《农机化研究》 北大核心 2026年第2期124-131,共8页
针对大型植物工厂采用固定式监测仪器难以对密集立体种植架中各位置种植对象进行长势监测和通过二维平面角度并不能完全反映叶菜生长状态的问题,提出了一种采用立体种植架穿梭车搭载监测仪器监测各位置种植对象长势的方法。以广良504绿... 针对大型植物工厂采用固定式监测仪器难以对密集立体种植架中各位置种植对象进行长势监测和通过二维平面角度并不能完全反映叶菜生长状态的问题,提出了一种采用立体种植架穿梭车搭载监测仪器监测各位置种植对象长势的方法。以广良504绿色包心生菜为对象,首先基于搭载的深度视觉相机,在第22、24、27、29 d提取种植期内4个时间点叶菜的RGB图像和点云图像,分别使用ImageJ和Python获取单个叶菜的投影面积和体积,同时使用电子秤称量叶菜鲜质量;然后通过多元线性回归分析,得到叶菜鲜质量与其平面投影面积、投影体积的线性回归模型,决定系数R^(2)=0.947;最后基于上述模型评估同期叶菜的质量,以验证模型的可靠性,模型评估平均误差为6.77%。所提出的叶菜长势监测方法性能优异,上述线性回归模型可实现种植期叶菜鲜质量无损评估。 展开更多
关键词 大型植物工厂 移动监测 叶菜长势 鲜质量评估 外形特征量 线性回归
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One Computational Method of the Eigenvalues of the Horizontal Vibration Problem of Beam 被引量:1
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作者 黄滨 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期277-282,共6页
This paper considers one computational method of the eigenvalues approximate value of the horizontal vibration problem of beam. The proof of our main result is based on the variational formula. First of all, Cauchy in... This paper considers one computational method of the eigenvalues approximate value of the horizontal vibration problem of beam. The proof of our main result is based on the variational formula. First of all, Cauchy inequality is used to obtain a basic inequality. Secondly, the functions of basis are made by Galerkin method, and the error estimates of eignevalues are obtained by Cauchy inequality. At last, the computational method of the approximate value of the eigenvalues turns out immediately, and acc... 展开更多
关键词 horizontal vibration problem of beam eigenvalue EIGENFUNCTION Galerkin method
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ASYMPTOTIC BEHAVIOUR OF EIGENVALUES FOR THE DISCONTINUOUS BOUNDARY-VALUE PROBLEM WITH FUNCTIONAL-TRANSMISSION CONDITIONS 被引量:12
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作者 O.Sh.Mukhtarov Department of Mathematics, Science and Arts Faculty, Gaziosmanpasa University, Tokat, TurkeyMustafa Kandemir Department of Mathematics, Faculty of A mas y a Education, Ondokuz Mayis University, Amasya, Turkey 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期335-345,共11页
In this study, the boundary-value problem with eigenvalue parameter generated by the differential equation with discontinuous coefficients and boundary conditions which contains not only endpoints of the considered in... In this study, the boundary-value problem with eigenvalue parameter generated by the differential equation with discontinuous coefficients and boundary conditions which contains not only endpoints of the considered interval, but also point of discontinuity and linear functionals is investigated. So, the problem is not pure boundary-value. The authors single out a class of linear functionals and find simple algebraic conditions on coefficients, which garantee the existence of infinit number eigenvalues. Also the asymptotic formulas for eigenvalues are found. 展开更多
关键词 Asymptotic behaviour of eigenvalues boundary-value problems functional-conditions discontinuous coefficients
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INEQUALITIES OF EIGENVALUES FOR BI-KOHN LAPLACIAN ON HEISENBERG GROUP 被引量:12
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作者 黄广月 陈文艺 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期125-131,共7页
In this article, we consider the eigenvalue problem for the bi-Kohn Laplacian and obtain universal bounds on the (k + 1)-th eigenvalue in terms of the first k eigenvalues independent of the domains.
关键词 EIGENVALUE universal bounds bi-Kohn Laplacian
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A SIMPLIFIED BRAUER'S THEOREM ON MATRIX EIGENVALUES 被引量:8
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作者 LiLuoluo Dept.ofScientific Com puting and Com puter Applications, Mathem atics and Com putation College, Zhong- shan Univ., Guangzhou 510275. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1999年第3期259-264,共6页
Let A= (aij)∈Cn×n and ri = ∑ j≠i|aij|. Suppose thatforeach row of A there isatleastonenonzero off-diagonalentry. Itis proved thatalleigenvalues ofAarecontained in Ω~= ∪aij≠0,i≠j{z∈C:|z- aii||z- ... Let A= (aij)∈Cn×n and ri = ∑ j≠i|aij|. Suppose thatforeach row of A there isatleastonenonzero off-diagonalentry. Itis proved thatalleigenvalues ofAarecontained in Ω~= ∪aij≠0,i≠j{z∈C:|z- aii||z- ajj|≤rirj}. The resultre- duces the num berofovals in originalBrauer'stheorem in m any cases. Eigenval- ues(and associated eigenvectors) thatlocate in theboundary ofΩ~ arediscussed. 展开更多
关键词 EIGENVALUE inclusion region directed graph.
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UNIVERSAL BOUNDS FOR EIGENVALUES OF LAPLACIAN OPERATOR OF ANY ORDER 被引量:7
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作者 黄广月 陈文艺 《Acta Mathematica Scientia》 SCIE CSCD 2010年第3期939-948,共10页
Let Ω be a connected bounded domain in R^n. Denote by λi the i-th eigenvalue of the Lapla^ian operator with any order p:{u=Эn→^-Эu=…=Эn→p-1^-Эp-1u=0 on ЭΩ (-△)pu=λu in Ω.In this article, we give som... Let Ω be a connected bounded domain in R^n. Denote by λi the i-th eigenvalue of the Lapla^ian operator with any order p:{u=Эn→^-Эu=…=Эn→p-1^-Эp-1u=0 on ЭΩ (-△)pu=λu in Ω.In this article, we give some expressions for upper bound of the (k + 1)-th eigenvalue )λk+l in terms of the first k eigenvalues. 展开更多
关键词 EIGENVALUE Laplacian operator
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ESTIMATES FOR EIGENVALUES OF FOURTH-ORDER WEIGHTED POLYNOMIAL OPERATOR 被引量:4
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作者 孙和军 陈大广 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期826-834,共9页
In this paper,we investigate the Dirichlet eigenvalue problem of fourth-order weighted polynomial operator △2u-a△u+bu=Λρu,inΩRn,u|Ω=uvΩ=0,where the constants a,b≥0.We obtain some estimates for the upper boun... In this paper,we investigate the Dirichlet eigenvalue problem of fourth-order weighted polynomial operator △2u-a△u+bu=Λρu,inΩRn,u|Ω=uvΩ=0,where the constants a,b≥0.We obtain some estimates for the upper bounds of the (k+1)-th eigenvalueΛ_k+1 in terms of the first k eigenvalues.Moreover,these results contain some results for the biharmonic operator. 展开更多
关键词 EIGENVALUE polynomial operator biharmonic operator
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ESTIMATES ON EIGENVALUES FOR THE BIHARMONIC OPERATOR ON A BOUNDED DOMAIN IN H^n(-1) 被引量:3
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作者 黄广月 李兴校 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1383-1388,共6页
In this paper, we consider eigenvalues of the Dirichlet biharmonic operator on a bounded domain in a hyperbolic space. We obtain universal bounds on the (k + 1)th eigenvalue in terms of the first kth eigenvalues in... In this paper, we consider eigenvalues of the Dirichlet biharmonic operator on a bounded domain in a hyperbolic space. We obtain universal bounds on the (k + 1)th eigenvalue in terms of the first kth eigenvalues independent of the domains. 展开更多
关键词 universal inequality EIGENVALUE hyperbolic space clamped plate problem
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EIGENVALUES OF A SPECIAL KIND OF SYMMETRIC BLOCK CIRCULANT MATRICES 被引量:3
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作者 WangLigong LiXueliang HoedeC 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第1期17-26,共10页
In this paper, the spectrum and characteristic polynomial for a special kind of symmetric block circulant matrices are given.
关键词 block circulant matrix EIGENVALUE characteristic polynomial integr al graph.
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An Efficient Technique for Finding the Eigenvalues of Fourth-Order Sturm-Liouville Problems 被引量:5
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作者 Mohamed El-Gamel Mona Sameeh 《Applied Mathematics》 2012年第8期920-925,共6页
In this work, we present a computational method for solving eigenvalue problems of fourth-order ordinary differential equations which based on the use of Chebychev method. The efficiency of the method is demonstrated ... In this work, we present a computational method for solving eigenvalue problems of fourth-order ordinary differential equations which based on the use of Chebychev method. The efficiency of the method is demonstrated by three numerical examples. Comparison results with others will be presented. 展开更多
关键词 Chebychev POLYNOMIAL FOURTH-ORDER STURM-LIOUVILLE EIGENVALUE
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LOWER BOUNDS OF DIRICHLET EIGENVALUES FOR A CLASS OF FINITELY DEGENERATE GRUSHIN TYPE ELLIPTIC OPERATORS 被引量:2
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作者 陈化 陈洪葛 +1 位作者 段忆芮 胡鑫 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1653-1664,共12页
Let Ω be a bounded open domain in Rn with smooth boundary Ω, X =(X1,X2,... ,Xm) be a system of real smooth vector fields defined on Ω and the bound-ary Ω is non-characteristic for X. If X satisfies the HSrmande... Let Ω be a bounded open domain in Rn with smooth boundary Ω, X =(X1,X2,... ,Xm) be a system of real smooth vector fields defined on Ω and the bound-ary Ω is non-characteristic for X. If X satisfies the HSrmander's condition, then the vectorfield is finitely degenerate and the sum of square operator △X =m∑j=1 X2 j is a finitely de-generate elliptic operator. In this paper, we shall study the sharp estimate of the Dirichlet eigenvalue for a class of general Grushin type degenerate elliptic operators △x on Ω. 展开更多
关键词 Dirichlet eigenvalues finitely degenerate elliptic operators HSrmander's con-dition sub-elliptic estimate Grushin type operator
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Derivatives of repeated eigenvalues and corresponding eigenvectors of damped systems 被引量:1
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作者 解惠青 戴华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第6期837-845,共9页
A procedure is presented for computing the derivatives of repeated eigenvalues and the corresponding eigenvectors of damped systems. The derivatives are calculated in terms of the eigenvalues and eigenvectors of the s... A procedure is presented for computing the derivatives of repeated eigenvalues and the corresponding eigenvectors of damped systems. The derivatives are calculated in terms of the eigenvalues and eigenvectors of the second-order system, and the use of rather undesirable state space representation is avoided. Hence the cost of computation is greatly reduced. The efficiency of the proposed procedure is illustrated by considering a 5-DOF non-proportionally damped system. 展开更多
关键词 eigenvalue derivatives eigenvector derivatives sensitivity analysis damped systems repeated eigenvalues
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Bounding the sum of powers of the Laplacian eigenvaluesof graphs 被引量:1
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作者 CHEN Xiao-dan QIAN Jian-guo 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第2期142-150,共9页
For a non-zero real number α, let sα(G) denote the sum of the αth power of thenon-zero Laplacian eigenvalues of a graph G. In this paper, we establish a connection betweensα(G) and the first Zagreb index in wh... For a non-zero real number α, let sα(G) denote the sum of the αth power of thenon-zero Laplacian eigenvalues of a graph G. In this paper, we establish a connection betweensα(G) and the first Zagreb index in which the H¨older’s inequality plays a key role. By usingthis result, we present a lot of bounds of sα(G) for a connected (molecular) graph G in terms ofits number of vertices (atoms) and edges (bonds). We also present other two bounds for sα(G)in terms of connectivity and chromatic number respectively, which generalize those results ofZhou and Trinajsti′c for the Kirchho? index [B Zhou, N Trinajsti′c. A note on Kirchho? index,Chem. Phys. Lett., 2008, 455: 120-123]. 展开更多
关键词 Laplacian eigenvalues the first Zagreb index Kirchhoff index CONNECTIVITY chromatic number.
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A NEW METHOD FOR ESTIMATING BOUNDS OF EIGENVALUES 被引量:1
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作者 Yang Xiaowei Chen Suhuan +1 位作者 Lian Huadong Yang Guang 《Acta Mechanica Solida Sinica》 SCIE EI 2001年第3期242-250,共9页
A new method for estimating the bounds of eigenvalues ispresented. In order to show that the method proposed is as effectiveas Qiu's an undamping spring-mass system with 5 nodes and 5 degrees ofreedom is given. To... A new method for estimating the bounds of eigenvalues ispresented. In order to show that the method proposed is as effectiveas Qiu's an undamping spring-mass system with 5 nodes and 5 degrees ofreedom is given. To illustrate that the present method can beapplied to structures which cannot be treated by non-negativedecomposition, a plane frame with 202 nodes and 357 beam elements isgiven. The results show that the present method is effective forestimating the bounds of eigenvalues and is more common than Qiu's. 展开更多
关键词 bounds of eigenvalues non-negative decomposition eigenvalue inclusiontheorem
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Petrochemical eigenvalues and diagrams for the identification of metamorphic rocks'protolith,taking the host rocks of Dashuigou tellurium deposit in China as an example 被引量:1
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作者 Jianzhao Yin Shoupu Xiang +2 位作者 Yuhong Chao Yuhan Yin Hongyun Shi 《Acta Geochimica》 EI CAS CSCD 2023年第1期103-124,共22页
The Dashuigou tellurium deposit is the world’s only known independent tellurium deposit.By restoring metamorphic rocks’protolith,we seek to understand not only the development and evolution trajectory of the region ... The Dashuigou tellurium deposit is the world’s only known independent tellurium deposit.By restoring metamorphic rocks’protolith,we seek to understand not only the development and evolution trajectory of the region but also the origin of the relevant deposits.While there are many ways to restore metamorphic rocks’protolith,we take the host metamorphic rocks of Dashuigou tellurium deposit and leverage various petrochemical eigenvalues and related diagrams previously proposed to reveal the deposit’s host metamorphic rocks’protolith.The petrochemical eigenvalues include molecular number,Niggli’s value,REE parity ratio,CaO/Al_(2)O_(3)ratio,Fe^(3+) /(Fe^(3+) -+Fe^(2+) )ratio,chondrite-normalized REE value,logarithmic REE value,various REE eigenvalues including scandium,Eu/Sm ratio,total REE amount,light and heavy REEs,δEu,Eu anomaly,Sm/Nd ratio,and silicon isotope δ^(30) SiNBS-29‰,etc.The petrochemical plots include ACMs,100 mg-c-(al+alk),SiO_(2)-(Na_(2)O+K_(2)O),(al+fm)-(c+alk)versus Si,FeO+Fe_(2)O^(3+) TiO)-Al_(2)O_(3)-MgO,c-mg,Al_(2)O_(3)-(Na_(2)O+K_(2)O),chondrite-normalized REE model,La/Yb-REE,and Sm/Nd ratio,etc.On the basis of these comprehensive analyses,the following conclusions are drawn,starting from the many mantle-derived types of basalt developed in the study area of different geological ages,combined with the previously published research results on the deposit s fluid inclusions and sulfur and lead isotopes.The deposit is formed by mantle degassing in the form of a mantle plume in the late Yanshanian orogeny.The degassed fluids are rich in nano-sc ale substances including Fe,Te,S,As,Bi,Au,Se,H_(2),CO_(2),N_(2),H_(2)O,and CH_(4),which are enriched by nano-effect,and then rise to a certain part of the crust in the form of mantle plume along the lithospheric fault to form the deposit.The ultimate power for tellurium mineralization was from H_(2)flow with high energy,which was produced through radiation from the melted iron of the Earth’s outer core.The H,flow results in the Earth’s degassing,as well as the mantle and crust’s uplift. 展开更多
关键词 Petrochemical diagrams and eigenvalue PROTOLITH Metamorphic rock Independent tellurium deposit Host rock The mantle plume
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Edge detection using directional eigenvalues of potential field gradient tensor data 被引量:2
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作者 ZHOU Shuai HUANG Danian 《Global Geology》 2015年第3期188-195,共8页
Edge detection of potential field interpretation is an important task. The traditional edge detection methods have poor ability in outlining weak amplitude anomalies clearly. The resolved edges position is blurred.We ... Edge detection of potential field interpretation is an important task. The traditional edge detection methods have poor ability in outlining weak amplitude anomalies clearly. The resolved edges position is blurred.We purposed new edge detection methods based on directional eigenvalues of potential field gradient tensor for the causative sources. In order to balance strong and weak amplitude anomalies simultaneously,we present one normalization method using different orders of vertical derivatives to improve the new filters. The presented filters were tested on synthetic and real potential field data to verify its feasibility. All of the results have shown that the new edge detection methods can not only display the sources edges precisely and clearly,but also bring out more geological subtle details. 展开更多
关键词 directional eigenvalues edge detection potential field
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THE UNCERTAIN EIGENVALUES ANALYSIS OF STRUCTURES WITH UNCERTAIN PARAMETERS 被引量:1
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作者 Guo Xuedong Xie Jun Chen Suhuan 《Acta Mechanica Solida Sinica》 SCIE EI 2000年第3期230-236,共7页
This paper presents a method for estimating the upper and lowerbounds of eigenvalues of structures with uncertainties. The uncertainparameters re described by the convex model. A numerical ex- ample ofthe frame struct... This paper presents a method for estimating the upper and lowerbounds of eigenvalues of structures with uncertainties. The uncertainparameters re described by the convex model. A numerical ex- ample ofthe frame structure is given to illustrate the efficiency of themethod. 展开更多
关键词 structures with uncertainties upper and lower bound of eigenvalues
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