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Morphological Characterization of Graphene Flake Networks Using Minkowski Functionals 被引量:1
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作者 Igor Levchenko Jinghua Fang +2 位作者 Kostya (Ken) Ostrikov Ludovico Lorello Michael Keidar 《Graphene》 2016年第1期25-34,共10页
Two Minkowski functionals were tested in the capacity of morphological descriptors to quantitatively compare the arrays of vertically-aligned graphene flakes grown on smooth and nanoporous alumina and silica surfaces.... Two Minkowski functionals were tested in the capacity of morphological descriptors to quantitatively compare the arrays of vertically-aligned graphene flakes grown on smooth and nanoporous alumina and silica surfaces. Specifically, the Euler-Poincaré characteristic and fractal dimension graphs were used to characterize the degree of connectivity and order in the systems, i.e. in the graphene flake patterns of petal-like and tree-like morphologies on solid substrates, and meshlike patterns (networks) grown on nanoporous alumina treated in low-temperature inductivelycoupled plasma. It was found that the Minkowski functionals return higher connectivity and fractal dimension numbers for the graphene flakepatterns with more complex morphologies, and indeed can be used as morphological descriptors to differentiate among various configurations of vertically-aligned graphene flakes grown on surfaces. 展开更多
关键词 Graphene Flakes Minkowski functionals Euler-Poincaré Characteristic Connectivity
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POSITIVE FUNCTIONALS ON ζ(R^n)
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作者 Ryszard Grzaslewicz 《Acta Mathematica Scientia》 SCIE CSCD 1990年第3期303-310,共8页
Let (E) be a space of operators on a finite dimensional Hilbert space E, and let (E) be its dual In this paper the positive part is considered for the unit ball of (E). We investigate the atructure of extremal subsets... Let (E) be a space of operators on a finite dimensional Hilbert space E, and let (E) be its dual In this paper the positive part is considered for the unit ball of (E). We investigate the atructure of extremal subsets of. In particular it is given a characterization of extreme pesitive functioals on (E). 展开更多
关键词 TH POSITIVE functionals ON R~n
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THEOREMS OF PEANO'S TYPE FOR BIVARIATE FUNCTIONS AND OPTIMAL RECOVERY OF LINEAR FUNCTIONALS
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作者 N.K. Dicheva (University of Architecture, Bulgaria) 《Analysis in Theory and Applications》 2001年第3期43-53,共11页
The best recovery of a linear functional Lf, f=f(x,y), on the basis of given linear functionals L jf,j=1,2,...,N in a sense of Sard has been investigated, using analogy of Peano's theorem. The best recovery of a ... The best recovery of a linear functional Lf, f=f(x,y), on the basis of given linear functionals L jf,j=1,2,...,N in a sense of Sard has been investigated, using analogy of Peano's theorem. The best recovery of a bivariate function by given scattered data has been obtained in a simple analytical form as a special case. 展开更多
关键词 Ky THEOREMS OF PEANO’S TYPE FOR BIVARIATE FUNCTIONS AND OPTIMAL RECOVERY OF LINEAR functionals
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Optimal control of quadratic functionals for affine nonlinear systems
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作者 M.Popescu A.Dumitrache 《Theoretical & Applied Mechanics Letters》 CAS 2012年第4期56-59,共4页
In this paper we analyze the optimal control problem for a class of afflne nonlinear systems under the assumption that the associated Lie algebra is nilpotent. The Lie brackets generated by the vector fields which def... In this paper we analyze the optimal control problem for a class of afflne nonlinear systems under the assumption that the associated Lie algebra is nilpotent. The Lie brackets generated by the vector fields which define the nonlinear system represent a remarkable mathematical instrument for the control of affine systems. We determine the optimal control which corresponds to the nilpotent operator of the first order. In particular, we obtain the control that minimizes the energy of the given nonlinear system. Applications of this control to bilinear systems with first order nilpotent operator are considered. 展开更多
关键词 optimal control affine nonlinear systems nilpotent operator quadratic functionals
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ON MULTIPLE WIENER INTEGRAL EXPANSIONS FOR D'-VALUED NONLINEAR RANDOM FUNCTIONALS
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作者 吴奖伦 《Acta Mathematica Scientia》 SCIE CSCD 1993年第2期220-228,共9页
In this paper, the multiple stochastic integral with respect to a Wiener D'-process is defined. And also it is shown that for a D'-valued nonlinear random functional there exists a sequence of multiple integra... In this paper, the multiple stochastic integral with respect to a Wiener D'-process is defined. And also it is shown that for a D'-valued nonlinear random functional there exists a sequence of multiple integral kernels such that the nonlinear functional can be expanded by series of multiple Wiener integrals of the integral kernels with respect to the Wiener D'-process. 展开更多
关键词 VALUED NONLINEAR RANDOM functionals ON MULTIPLE WIENER INTEGRAL EXPANSIONS FOR D ONB
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New Approach of Stability for Time-Delay Takagi-Sugeno Fuzzy System Based on Fuzzy Weighting-Dependent Lyapunov Functionals
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作者 Yassine Manai Mohamed Benrejeb Pierre Borne 《Applied Mathematics》 2011年第11期1339-1345,共7页
This paper deals with the stability of Takagi-Sugeno fuzzy models with time delay. Using fuzzy weighting- dependent Lyapunov-Krasovskii functionals, new sufficient stability criteria are established in terms of Linear... This paper deals with the stability of Takagi-Sugeno fuzzy models with time delay. Using fuzzy weighting- dependent Lyapunov-Krasovskii functionals, new sufficient stability criteria are established in terms of Linear Matrix Inequality;hence the stability bound of upper bound delay time can be easily estimated. Finally, numeric simulations are given to validate the developed approach. 展开更多
关键词 TAKAGI-SUGENO FUZZY Models Linear Matrix Inequalities LMIS FUZZY Weighting-Dependent LYAPUNOV-KRASOVSKII functionals
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Markov process functionals in finance and insurance 被引量:7
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作者 GENG Xian-min LI Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第1期21-26,共6页
The Markov property of Markov process functionals which are frequently used in economy, finance, engineering and statistic analysis is studied. The conditions to judge Markov property of some important Markov process ... The Markov property of Markov process functionals which are frequently used in economy, finance, engineering and statistic analysis is studied. The conditions to judge Markov property of some important Markov process functionals are presented, the following conclusions are obtained: the multidimensional process with independent increments is a multidimensional Markov process; the functional in the form of path integral of process with independent increments is a Markov process; the surplus process with the doubly stochastic Poisson process is a vector Markov process. The conditions for linear transformation of vector Markov process being still a Markov process are given. 展开更多
关键词 Markov process functional process with independent increments risk process
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Observer-Based Adaptive Fuzzy Tracking Control Using Integral Barrier Lyapunov Functionals for A Nonlinear System With Full State Constraints 被引量:3
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作者 Wei Zhao Yanjun Liu Lei Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第3期617-627,共11页
A new fuzzy adaptive control method is proposed for a class of strict feedback nonlinear systems with immeasurable states and full constraints.The fuzzy logic system is used to design the approximator,which deals with... A new fuzzy adaptive control method is proposed for a class of strict feedback nonlinear systems with immeasurable states and full constraints.The fuzzy logic system is used to design the approximator,which deals with uncertain and continuous functions in the process of backstepping design.The use of an integral barrier Lyapunov function not only ensures that all states are within the bounds of the constraint,but also mixes the states and errors to directly constrain the state,reducing the conservativeness of the constraint satisfaction condition.Considering that the states in most nonlinear systems are immeasurable,a fuzzy adaptive states observer is constructed to estimate the unknown states.Combined with adaptive backstepping technique,an adaptive fuzzy output feedback control method is proposed.The proposed control method ensures that all signals in the closed-loop system are bounded,and that the tracking error converges to a bounded tight set without violating the full state constraint.The simulation results prove the effectiveness of the proposed control scheme. 展开更多
关键词 Adaptive control backstepping design integral barrier Lyapunov function(iBLF) states observer
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On the Variational Problems of the Functionals with Derivatives of Higher Orders and Undetermined Boundary 被引量:1
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作者 老大中 谈天民 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期116-121,共6页
According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of va... According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of variations are researched, the functionals depend on single argument, arbitrary unknown functions and their derivatives of higher orders. A new view point is posed and demonstrated, i.e. when the first variation of the functional is equal to zero, all the variational terms are not independent to each other, and at least one of them is equal to zero. Some theorems and corollaries of the variational problems of the functionals are obtained. 展开更多
关键词 calculus of variations FUNCTIONAL variational problems derivatives of higher orders undetermined boundary
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REPRESENTATION OF ADDITIVE FUNCTIONALS AND LOCAL TIMES FOR JUMP MARKOV PROCESSES AND THEIR FUNCTIONAL LIMIT THEOREM
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作者 蒋义文 刘禄勤 《Acta Mathematica Scientia》 SCIE CSCD 2003年第1期117-123,共7页
The representation of additive functionals and local times for jump Markov processes are obtained. The results of uniformly functional moderate deviation and their applications to birth-death processes are also presen... The representation of additive functionals and local times for jump Markov processes are obtained. The results of uniformly functional moderate deviation and their applications to birth-death processes are also presented. 展开更多
关键词 Additive functional Q-PROCESS local time moderate devaition jump process
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YET ON LINEAR STRUCTURES OF NORM-ATTAINING FUNCTIONALS ON ASPLUND SPACES
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作者 程立新 罗思捷 《Acta Mathematica Scientia》 SCIE CSCD 2018年第1期151-156,共6页
In this paper, we show that if an Asplund space X is either a Banach lattice or a quotient space of C(K), then it can be equivalently renormed so that the set of norm- attaining functionals contains an infinite dime... In this paper, we show that if an Asplund space X is either a Banach lattice or a quotient space of C(K), then it can be equivalently renormed so that the set of norm- attaining functionals contains an infinite dimensional closed subspace of X* if and only if X* contains an infinite dimensional reflexive subspace, which gives a partial answer to a question of Bandyopadhyay and Godefroy. 展开更多
关键词 norm-attaining functional Asplund space Banach lattice reflexive subspace Banach space
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ON THE RESPONSE FUNCTIONALS OF MATERIALS FOR THE IRREVERSIBLE PROCESSES OF THERMODYNAMICS
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作者 胡建阳 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1994年第3期60-65,共6页
Based on the continuum physics and taking into account variation of the heat dissipation, Helmholtz free ener-gy, internal energy and exothermicity with the thermodynamic process, in this paper, the functional equatio... Based on the continuum physics and taking into account variation of the heat dissipation, Helmholtz free ener-gy, internal energy and exothermicity with the thermodynamic process, in this paper, the functional equations of the general-ized stress and entropy associated ivith the time and temperature are derived for the irreversible process of thermoviscoelastic-plastic materials. As an example, the response functionals of Maxwell viscoelastic materials are obtained. 展开更多
关键词 viscoelasto-plastic materials irreversible process response functional generalized stress ENTROPY heat dissipation
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LOWER SEMICONTINUITY OF A CLASS OF FUNCTIONALSIN SBV_H
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作者 SongYingqing YangXiaoping LongFei 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第1期27-34,共8页
In this paper lower semicontinuity of the functional I(u)=∫_Ωf(x,u,Δ~ _Hu)dx is investigated for f being a Carathéodory function defined on Hn×R×R^2n and for u∈SBV_H(Ω),where Hn is the Heisenberg g... In this paper lower semicontinuity of the functional I(u)=∫_Ωf(x,u,Δ~ _Hu)dx is investigated for f being a Carathéodory function defined on Hn×R×R^2n and for u∈SBV_H(Ω),where Hn is the Heisenberg group with dimension 2n+1,ΩHn is an open set and Δ~ _Hu denotes the approximate derivative of the absolute continuous part Da_Hu with respect to D_Hu.In addition,a Lusin type approximation theorem for a SBV_H function is proved. 展开更多
关键词 lower semicontinuity SBV_H function Heisenberg group Lusin approximation.
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APPROXIMATION OF ADDITIVE FUNCTIONALS OF THE SYMMETRIC HUNT PROCESSES AND ITS APPLICATION
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作者 冯玉瑚 《Journal of China Textile University(English Edition)》 EI CAS 1996年第2期84-92,共9页
Approximate theorem of positive continuous additive functionals is discussed and then used to give a d-dimensional analogue to the representation of additive functiouals of one-dimensional Brownian Motion with respect... Approximate theorem of positive continuous additive functionals is discussed and then used to give a d-dimensional analogue to the representation of additive functiouals of one-dimensional Brownian Motion with respect to local time. 展开更多
关键词 : SYMMETRIC HUNT process ADDITIVE functional SMOOTH measure BROWNIAN motion local time
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THE REGULARITY OF QUASI-MINIMA AND ω-MINIMA OF INTEGRAL FUNCTIONALS
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作者 宁正元 王秀丽 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1301-1317,共17页
In this article, we have two parts. In the first part, we are concerned with the locally Hlder continuity of quasi-minima of the following integral functional ∫Ωf(x, u, Du)dx, (1) where Ω is an open subset of E... In this article, we have two parts. In the first part, we are concerned with the locally Hlder continuity of quasi-minima of the following integral functional ∫Ωf(x, u, Du)dx, (1) where Ω is an open subset of Euclidean N-space (N ≥ 3), u:Ω → R,the Carath′eodory function f satisfies the critical Sobolev exponent growth condition |Du|^p* |u|^p*-a(x) ≤ f(x,u,Du) ≤ L(|Du|^p+|u|^p* + a(x)), (2) where L≥1, 1pN,p^* = Np/N-p , and a(x) is a nonnegative function that lies in a suitable Lp space. In the second part, we study the locally Hlder continuity of ω-minima of (1). Our method is to compare the ω-minima of (1) with the minima of corresponding function determined by its critical Sobolev exponent growth condition. Finally, we obtain the regularity by Ekeland’s variational principal. 展开更多
关键词 Integral functional Q-minima ω-minima Ekeland’s variational principle Hlder continuous
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TRANSFORMATION OF SYMMETRIC MULTIPLICATIVE FUNCTIONALS
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作者 AnHong YingJiangang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第4期451-457,共7页
In the present paper the transformation of symmetric Markov processes by symmetric martingale multiplicative functionals is studied and the corresponding Dirichlet form is formulated.
关键词 Markov processes Dirichlet forms multiplicative functional.
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A RELAXATION RESULT OF FUNCTIONALS IN THE SPACE SBD(Ω)
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作者 吕中学 杨孝平 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期770-778,共9页
In this article,the authors obtain an integral representation for the relaxation of the functionalF(x,u,Ω):={∫^f(x,u(x),εu(x))dx Ω if u∈W^1,1(Ω,R^N), +∞ otherwise, in the space of functions of bound... In this article,the authors obtain an integral representation for the relaxation of the functionalF(x,u,Ω):={∫^f(x,u(x),εu(x))dx Ω if u∈W^1,1(Ω,R^N), +∞ otherwise, in the space of functions of bounded deformation,with respect to L^1-convergence.Here Eu represents the absolutely continuous part of the symmetrized distributional derivative Eu.f(x,p,ξ)satisfying weak convexity assumption. 展开更多
关键词 Integral representation RELAXATION special functions with bounded deformation
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THE MAXIMUM OF THE γ-MAX-SUBADDITIVE FUNCTIONALS ON A CLASS OF TOPOLOGICAL GROUPS
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作者 定光桂 《Acta Mathematica Scientia》 SCIE CSCD 1998年第3期310-314,共5页
It is shown that if a 'max-subadditive funtional' p(x) defined on some symmetric neighborhood U0 of zero vector θ in a 'b.f.-toplological group' X is 'upper semi-cotinuous' at a point x0 ∈ U0... It is shown that if a 'max-subadditive funtional' p(x) defined on some symmetric neighborhood U0 of zero vector θ in a 'b.f.-toplological group' X is 'upper semi-cotinuous' at a point x0 ∈ U0, or 'lower semi-continuous' in some neighborhood V(x0) U0 and X is of second category; then p(x) can attain its supremum in U0. And there is a similar conclusion for the γ-max-subadditive functional when its supremum is 0 and if U0 is 'pseudo-bounded' set in X. 展开更多
关键词 γ-max-subadditive functional Binary fissionable topological group Pseudo bounded set.
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Modeling Distortion Signals of Power Grid Based on Wiener-G Functionals
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作者 Xiao-Bing Zhang Yun-Hui Li Guo-Zhi Fang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第3期79-84,共6页
The uniform mathematical model of distortion signals in power grid has been setup with the theory of Wiener-G Functional. Firstly,the Matlab simulation models were established. Secondly,the Wiener kernel of power load... The uniform mathematical model of distortion signals in power grid has been setup with the theory of Wiener-G Functional. Firstly,the Matlab simulation models were established. Secondly,the Wiener kernel of power load was found based on the Gaussian white noise as input. And then the uniform mathematical model of the power grid signal was established according to the homogeneous of the same order of Wiener functional series. Finally,taking three typical distortion sources which are semiconductor rectifier,electric locomotive and electric arc furnace in power grid as examples,we have validated the model through the Matlab simulation and analyzed the simulation errors. The results show that the uniform mathematical model of distortion signals in power grid can approximation the actual model by growing the items of the series under the condition of the enough storage space and computing speed. 展开更多
关键词 electric energy measurement distortion signals model of power grid signal functional series Wiener kernel
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Functionals and Functional Derivatives of Wave Functions and Densities
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作者 A. Gonis 《World Journal of Condensed Matter Physics》 2014年第3期179-199,共21页
It is shown that the process of conventional functional differentiation does not apply to functionals whose domain (and possibly range) is subject to the condition of integral normalization, as is the case with respec... It is shown that the process of conventional functional differentiation does not apply to functionals whose domain (and possibly range) is subject to the condition of integral normalization, as is the case with respect to a domain defined by wave functions or densities, in which there exists no neighborhood about a given element in the domain defined by arbitrary variations that also lie in the domain. This is remedied through the generalization of the domain of a functional to include distributions in the form of , where ?is the Dirac delta function and is a real number. This allows the determination of the rate of change of a functional with respect to changes of the independent variable determined at each point of the domain, with no reference needed to the values of the functional at different functions in its domain. One feature of the formalism is the determination of rates of change of general expectation values (that may not necessarily be functionals of the density) with respect to the wave functions or the densities determined by the wave functions forming the expectation value. It is also shown that ignoring the conditions of conventional functional differentiation can lead to false proofs, illustrated through a flaw in the proof that all densities defined on a lattice are -representable. In a companion paper, the mathematical integrity of a number of long-standing concepts in density functional theory are studied in terms of the formalism developed here. 展开更多
关键词 FUNCTIONAL FUNCTIONAL Derivative FUNCTIONAL Derivative of WAVE Functions FUNCTIONAL DERIVATIVES with RESPECT to WAVE Functions FUNCTIONAL DERIVATIVES with RESPECT to Density RATE of CHANGE of a FUNCTIONAL RATE of CHANGE of Expectation Values RATE of CHANGE of a WAVE Function
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