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The potential mechanism and clinical application value of remote ischemic conditioning in stroke 被引量:1
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作者 Yajun Zhu Xiaoguo Li +6 位作者 Xingwei Lei Liuyang Tang Daochen Wen Bo Zeng Xiaofeng Zhang Zichao Huang Zongduo Guo 《Neural Regeneration Research》 SCIE CAS 2025年第6期1613-1627,共15页
Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may... Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may be related to neuroinflammation, cellular immunity, apoptosis, and autophagy, the exact underlying molecular mechanisms are unclear. This review summarizes the current status of different types of remote ischemic conditioning methods in animal and clinical studies and analyzes their commonalities and differences in neuroprotective mechanisms and signaling pathways. Remote ischemic conditioning has emerged as a potential therapeutic approach for improving stroke-induced brain injury owing to its simplicity, non-invasiveness, safety, and patient tolerability. Different forms of remote ischemic conditioning exhibit distinct intervention patterns, timing, and application range. Mechanistically, remote ischemic conditioning can exert neuroprotective effects by activating the Notch1/phosphatidylinositol 3-kinase/Akt signaling pathway, improving cerebral perfusion, suppressing neuroinflammation, inhibiting cell apoptosis, activating autophagy, and promoting neural regeneration. While remote ischemic conditioning has shown potential in improving stroke outcomes, its full clinical translation has not yet been achieved. 展开更多
关键词 Akt apoptosis autophagy cerebral perfusion cerebral vascular stenosis clinical transformation hemorrhagic stroke ischemic stroke NEUROINFLAMMATION neuroprotection Notch1 PI3K remote ischemic conditioning STROKE
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Actuator fault diagnosis and severity identification of turbofan engines for steady-state and dynamic conditions
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作者 Yuzhi CHEN Weigang ZHANG +4 位作者 Zhiwen ZHAO Elias TSOUTSANIS Areti MALKOGIANNI Yanhua MA Linfeng GOU 《Chinese Journal of Aeronautics》 2025年第1期427-443,共17页
Actuator faults can be critical in turbofan engines as they can lead to stall,surge,loss of thrust and failure of speed control.Thus,fault diagnosis of gas turbine actuators has attracted considerable attention,from b... Actuator faults can be critical in turbofan engines as they can lead to stall,surge,loss of thrust and failure of speed control.Thus,fault diagnosis of gas turbine actuators has attracted considerable attention,from both academia and industry.However,the extensive literature that exists on this topic does not address identifying the severity of actuator faults and focuses mainly on actuator fault detection and isolation.In addition,previous studies of actuator fault identification have not dealt with multiple concurrent faults in real time,especially when these are accompanied by sudden failures under dynamic conditions.This study develops component-level models for fault identification in four typical actuators used in high-bypass ratio turbofan engines under both dynamic and steady-state conditions and these are then integrated with the engine performance model developed by the authors.The research results reported here present a novel method of quantifying actuator faults using dynamic effect compensation.The maximum error for each actuator is less than0.06%and 0.07%,with average computational time of less than 0.0058 s and 0.0086 s for steady-state and transient cases,respectively.These results confirm that the proposed method can accurately and efficiently identify concurrent actuator fault for an engine operating under either transient or steady-state conditions,even in the case of a sudden malfunction.The research results emonstrate the potential benefit to emergency response capabilities by introducing this method of monitoring the health of aero engines. 展开更多
关键词 Turbofan engines Actuators Real time systems Fault identification Steady-state conditions Dynamic conditions
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FedCLCC:A personalized federated learning algorithm for edge cloud collaboration based on contrastive learning and conditional computing
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作者 Kangning Yin Xinhui Ji +1 位作者 Yan Wang Zhiguo Wang 《Defence Technology(防务技术)》 2025年第1期80-93,共14页
Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure ... Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure challenges in edge environments.However,the diversity of clients in edge cloud computing presents significant challenges for FL.Personalized federated learning(pFL)received considerable attention in recent years.One example of pFL involves exploiting the global and local information in the local model.Current pFL algorithms experience limitations such as slow convergence speed,catastrophic forgetting,and poor performance in complex tasks,which still have significant shortcomings compared to the centralized learning.To achieve high pFL performance,we propose FedCLCC:Federated Contrastive Learning and Conditional Computing.The core of FedCLCC is the use of contrastive learning and conditional computing.Contrastive learning determines the feature representation similarity to adjust the local model.Conditional computing separates the global and local information and feeds it to their corresponding heads for global and local handling.Our comprehensive experiments demonstrate that FedCLCC outperforms other state-of-the-art FL algorithms. 展开更多
关键词 Federated learning Statistical heterogeneity Personalized model conditional computing Contrastive learning
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Riemann-Hilbert Problem and Multiple High-order Poles Solutions of the Focusing mKdV Equation with Nonzero Boundary Conditions
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作者 Zi-yi WANG Shou-fu TIAN Jin-jie YANG 《Acta Mathematicae Applicatae Sinica》 2025年第1期234-251,共18页
The focusing modified Korteweg-de Vries(mKdV)equation with multiple high-order poles under the nonzero boundary conditions is first investigated via developing a Riemann-Hilbert(RH)approach.We begin with the asymptoti... The focusing modified Korteweg-de Vries(mKdV)equation with multiple high-order poles under the nonzero boundary conditions is first investigated via developing a Riemann-Hilbert(RH)approach.We begin with the asymptotic property,symmetry and analyticity of the Jost solutions,and successfully construct the RH problem of the focusing mKdV equation.We solve the RH problem when 1/S_(11)(k)has a single highorder pole and multiple high-order poles.Furthermore,we derive the soliton solutions of the focusing mKdV equation which corresponding with a single high-order pole and multiple high-order poles,respectively.Finally,the dynamics of one-and two-soliton solutions are graphically discussed. 展开更多
关键词 Riemann-Hilbert approach focusing mKdV equation nonzero boundary conditions multiple high-order poles soliton solutions
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Necessary and Sufficient Conditions in Smooth Programming with Generalized Convexity 被引量:1
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作者 孙清滢 叶留青 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期33-37,共5页
Hanson and Mond have grven sets of necessary and sufficient conditions for optimality in constrained optimization by introducing classes of generalized functions, called type Ⅰ functions. Recently, Bector definded un... Hanson and Mond have grven sets of necessary and sufficient conditions for optimality in constrained optimization by introducing classes of generalized functions, called type Ⅰ functions. Recently, Bector definded univex functions, a new class of functions that unifies several concepts of generalized convexity. In this paper, additional conditions are attached to the Kuhn Tucker conditions giving a set of conditions which are both necessary and sufficient for optimality in constrained optimization, under appropriate constraint qualifications. 展开更多
关键词 necessary and sufficient conditions generalized convexity nonlinear programming multiobjective programming type functions
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A NECESSARY AND SUFFICIENT CONDITION FOR SINGULAR NONLINEAR SECOND-ORDER BOUNDARY VALUE PROBLEMS TO HAVE POSITIVE SOLUTIONS 被引量:1
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作者 ZHAO ZENGQIN 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1998年第1期15-24,共10页
In this paper the following result is obtained: Suppose f(x,u,v) is nonnegative, continuous in ( a, b)×R +×R +; f may be singular at x=a (and/or x=b ) and v=0; f is nondecreasing on u for each x,v,... In this paper the following result is obtained: Suppose f(x,u,v) is nonnegative, continuous in ( a, b)×R +×R +; f may be singular at x=a (and/or x=b ) and v=0; f is nondecreasing on u for each x,v, nonincreasing on v for each x,u; there exists a constant q∈(0,1) such that t qf(x,t -1 u,tu)f(x,u,u)λ qf(x,λ -1 u,λu),0<t<1<λ, u∈R +. Then a necessary and sufficient condition for the equation u″+f(x,u,u)=0 on the boundary condition αu(a)-βu′(a)=0, γ(b)+δu′(b)=0 to have C 1(I) nonzero solutions is that 0<∫ b af(x,e(x),e(x))dx<∞, where α,β,γ,δ are nonnegative real numbers, Δ=(b-a)αγ+αδ+βγ>0, e(x)=G(x,x), G(x,y) is Green's function of above mentioned boundary value problem (when f(x,u,v)≡0). Received September 9,1996. Revised March 31,1997. 1991 MR Subject Classification: 34B. 展开更多
关键词 Second order boundary value problems singular differential equation necessary and sufficient condition.
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New sufficient conditions for general linear SISO Takagi-Sugeno fuzzy systems as universal approximators
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作者 申瑞玲 韩正忠 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期375-378,共4页
By the best approximation theory, it is first proved that the SISO (single-input single-output) linear Takagi-Sugeno (TS) fuzzy systems can approximate an arbitrary polynomial which, according to Weierstrass appro... By the best approximation theory, it is first proved that the SISO (single-input single-output) linear Takagi-Sugeno (TS) fuzzy systems can approximate an arbitrary polynomial which, according to Weierstrass approximation theorem, can uniformly approximate any continuous functions on the compact domain. Then new sufficient conditions for general linear SISO TS fuzzy systems as universal approximators are obtained. Formulae are derived to calculate the number of input fuzzy sets to satisfy the given approximation accuracy. Then the presented result is compared with the existing literature's results. The comparison shows that the presented result needs less input fuzzy sets, which can simplify the design of the fuzzy system, and examples are given to show its effectiveness. 展开更多
关键词 Takagi-Sugeno (TS) fuzzy system universal approximator sufficient condition
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Sufficient conditions of Rayleigh-Taylor stability and instability in equatorial ionosphere 被引量:2
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作者 Sicheng WANG Sixun HUANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第2期181-192,共12页
Rayleigh-Taylor (R-T) instability is known as the fundamental mechanism of equatorial plasma bubbles (EPBs). However, the sufficient conditions of R-T instability and stability have not yet been derived. In the pr... Rayleigh-Taylor (R-T) instability is known as the fundamental mechanism of equatorial plasma bubbles (EPBs). However, the sufficient conditions of R-T instability and stability have not yet been derived. In the present paper, the sufficient conditions of R-T stability and instability are preliminarily^derived. Linear equations for small perturbation are first obtained from the electron/ion continuity equations, momentum equations, and the current continuity equation in the equatorial ionosphere. The linear equations can be casted as an eigenvalue equation using a normal mode method. The eigenvalue equation is a variable coefficient linear equation that can be solved using a variational approach. With this approach, the sufficient conditions can be obtained as follows: if the minimum systematic eigenvalue is greater than one, the ionosphere is R-T unstable; while if the maximum systematic eigenvalue is less than one, the ionosphere is R-T stable. An approximate numerical method for obtaining the systematic eigenvalues is introduced, and the R-T stable/unstable areas are calculated. Numerical experiments axe designed to validate the sufficient conditions. The results agree with the derived suf- ficient conditions. 展开更多
关键词 Rayleigh-Taylor (R-T) instability sufficient condition equatorial iono-sphere variational approach
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ON THE NECESSARY AND SUFFICIENT CONDITIONS TO SOLVE A HEAT EQUATION WITH GENERAL ADDITIVE GAUSSIAN NOISE 被引量:2
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作者 Yaozhong HU Yanghui LIU 《Acta Mathematica Scientia》 SCIE CSCD 2019年第3期669-690,共22页
In this note, we consider stochastic heat equation with general additive Gaussian noise. Our aim is to derive some necessary and sufficient conditions on the Gaussian noise in order to solve the corresponding heat equ... In this note, we consider stochastic heat equation with general additive Gaussian noise. Our aim is to derive some necessary and sufficient conditions on the Gaussian noise in order to solve the corresponding heat equation. We investigate this problem invoking two differen t met hods, respectively, based on variance compu tations and on pat h-wise considerations in Besov spaces. We are going to see that, as anticipated, both approaches lead to the same necessary and sufficient condition on the noise. In addition, the path-wise approach brings out regularity results for the solution. 展开更多
关键词 Stochastic heat equation general Gaussian noise L^(2) solution sufficient and necessary condition Wong-Zakai approximation pathwise solution Holder continuity Besov space
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Sufficient Optimality Conditions for Multiobjective Programming Involving (V, ρ)h,ψ-type Ⅰ Functions 被引量:3
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作者 ZHANG Qing-xiang JIANG Yan KANG Rui-rui 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期409-416,共8页
New classes of functions namely (V, ρ)_(h,φ)-type I, quasi (V, ρ)_(h,φ)-type I and pseudo (V, ρ)_(h,φ)-type I functions are defined for multiobjective programming problem by using BenTal's generalized algebr... New classes of functions namely (V, ρ)_(h,φ)-type I, quasi (V, ρ)_(h,φ)-type I and pseudo (V, ρ)_(h,φ)-type I functions are defined for multiobjective programming problem by using BenTal's generalized algebraic operation. The examples of (V, ρ)_(h,φ)-type I functions are given. The sufficient optimality conditions are obtained for multi-objective programming problem involving above new generalized convexity. 展开更多
关键词 multiobjective programming (V p)h φ-type I functions Pareto efficient solu-tion sufficient optimality conditions
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Necessary and Sufficient Conditions for Reactive Azeotropes in Multi-reaction Mixtures in Terms of Elemental Composition 被引量:1
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作者 林金清 李浩然 韩世钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第4期361-365,共5页
Necessary and sufficient conditions for azeotropy in reactive mixtures are derived in terms of elemental composition, which shows that in the space of elemental compositions, they take the same functional form as the ... Necessary and sufficient conditions for azeotropy in reactive mixtures are derived in terms of elemental composition, which shows that in the space of elemental compositions, they take the same functional form as the conditions for azeotropy in non-reactive mixtures. The production of methyl tert-butyl ether (MTBE) is taken as an example. It is found that there are a 'pseudo' intermediate-boiling ternary reactive azeotrope at p = 101.325kPa and two 'real' ternary reactive azeotropes at p = 101.325 Pa. The introduced elemental compositions also reduce the dimensionality of the phase diagrams and provide a natural set of variables for visualization of phase behavior. 展开更多
关键词 reactive azeotropy necessary and sufficient condition multi-reactive mixture phase and chemical equilibrium
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SIMPLE SUFFICIENT CONDITIONS OF NONSINGULAR H-MATRICES 被引量:1
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作者 Huang Tingzhu Wang Guangbin(Dept.of Appl.Math .,University of Electronic Science and Technology of China,Chengdu 610054,PRC) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第S1期83-85,共3页
1 IntroductionH-matrices have important role in numerical analysis and matrix theory,etc.In thispaper,several practical criteria for H-matrices are obtained,to which the matrix is notnecessary be a diagonally dominant... 1 IntroductionH-matrices have important role in numerical analysis and matrix theory,etc.In thispaper,several practical criteria for H-matrices are obtained,to which the matrix is notnecessary be a diagonally dominant matrix,and the numbers of rows which are not diago-nal dominant can be n-1.We introduce the concept of α-diagonally dominant matrix,andby using the concept to investigate H-matrices. 展开更多
关键词 MATH In 二回 SIMPLE sufficient conditionS OF NONSINGULAR H-MATRICES
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NECESSARY AND SUFFICIENT CONDITIONS OF EXISTENCE AND UNIQUENESS OF LIMIT CYCLES FOR A CLASS OF POLYNOMIAL SYSTEM 被引量:1
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作者 刘德明 《Acta Mathematica Scientia》 SCIE CSCD 1991年第1期65-71,共7页
In this paper, we discuss the limit cycles of the systemdx/dt=y·[1+(A(x)]oy/dt=(-x+δy+α_1x^2+α_2xy+α_5x^2y)[1+B(x)] (1)where A(x)=sum form i=1 to n(a_ix~), B(x)=sum form j=1 to m(β_jx^j) and 1+B(x)>0. We ... In this paper, we discuss the limit cycles of the systemdx/dt=y·[1+(A(x)]oy/dt=(-x+δy+α_1x^2+α_2xy+α_5x^2y)[1+B(x)] (1)where A(x)=sum form i=1 to n(a_ix~), B(x)=sum form j=1 to m(β_jx^j) and 1+B(x)>0. We prove that (1) possesses at most one limit cycle and give out the necessary and sufficient conditions of existence and uniqueness of limit cycles. 展开更多
关键词 NECESSARY AND sufficient conditionS OF EXISTENCE AND UNIQUENESS OF LIMIT CYCLES FOR A CLASS OF POLYNOMIAL SYSTEM LIM
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A NECESSARY AND A SUFFICIENT CONDITION FOR THE EXISTENCE OF THE POSITIVE RADIAL SOLUTIONS TO HESSIAN EQUATIONS AND SYSTEMS WITH WEIGHTS 被引量:7
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作者 Dragos-Patru COVEI 《Acta Mathematica Scientia》 SCIE CSCD 2017年第1期47-57,共11页
In this article, we consider the existence of positive radial solutions for Hessian equations and systems with weights and we give a necessary condition as well as a sufficient condition for a positive radial solution... In this article, we consider the existence of positive radial solutions for Hessian equations and systems with weights and we give a necessary condition as well as a sufficient condition for a positive radial solution to be large. The method of proving theorems is essentially based on a successive approximation technique. Our results complete and improve a work published recently by Zhang and Zhou(existence of entire positive k-convex radial solutions to Hessian equations and systems with weights. Applied Mathematics Letters,Volume 50, December 2015, Pages 48–55). 展开更多
关键词 EXISTENCE Keller-Osserman condition k-Hessian equation and system
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Comparison on Sufficient Conditions for the Stability of Hill Equation: An Arnold’s Tongues Approach 被引量:1
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作者 Carlos A. Franco Joaquin Collado 《Applied Mathematics》 2017年第10期1481-1514,共34页
It is known that the solutions of a second order linear differential equation with periodic coefficients are almost always analytically impossible to obtain and in order to study its properties we often require a comp... It is known that the solutions of a second order linear differential equation with periodic coefficients are almost always analytically impossible to obtain and in order to study its properties we often require a computational approach. In this paper we compare graphically, using the Arnold Tongues, some sufficient criteria for the stability of periodic differential equations. We also present a brief explanation on how the authors, of each criterion, obtained them. And a comparison between four sufficient stability criteria and the stability zones found by perturbation methods is presented. 展开更多
关键词 Periodic Differential Equations Stability sufficient Criteria HILL Equation HAMILTONIAN LYAPUNOV Characteristic Constant
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A SUFFICIENT CONDITION OF CONVERGENCE FOR CLIFFORD CONTINUED FRACTIONS
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作者 李永群 王仙桃 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期8-14,共7页
In this article, a sufficient condition for a Clifford continued fraction to be convergent is established, and some applications are given.
关键词 Clifford continued fraction sufficient condition CONVERGENCE APPLICATION
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ON A CLASS OF BESICOVITCH FUNCTIONS TO HAVE EXACT BOX DIMENSION: A NECESSARY AND SUFFICIENT CONDITION 被引量:1
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作者 ZhouSongping HeGuolong 《Analysis in Theory and Applications》 2004年第2期175-181,共7页
This paper summarized recent achievements obtained by the authors about the box dimensions of the Besicovitch functions given bywhere 1 < s < 2, λk> tends to infinity as k→∞ and λk satisfies λk+1/λk≥λ... This paper summarized recent achievements obtained by the authors about the box dimensions of the Besicovitch functions given bywhere 1 < s < 2, λk> tends to infinity as k→∞ and λk satisfies λk+1/λk≥λ>1. The results show thatis a necessary and sufficient condition for Graph(B(t)) to have same upper and lower box dimensions. For the fractional Riemann-Liouvtlle differential operator Du and the fractional integral operator D-v, the results show that if A is sufficiently large, then a necessary and sufficient condition for box dimensionof Graph(D-v(B)), 0 < v < s - 1, to be s - v and box dimension of Graph(Du(B)), 0 < u < 2 - s, to bes + u is also lim. 展开更多
关键词 Weierstrass function Besicovitch function fractal dimension box dimension Hard- mard condition
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The convergence rate and necessary-and-sufficient condition for the consistency of isogeometric collocation method
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作者 LIN Hong-wei XIONG Yun-yang +2 位作者 HU Hui YAN Jia-cong HU Qian-qian 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第2期272-289,共18页
Although the isogeometric collocation(IGA-C)method has been successfully utilized in practical applications due to its simplicity and efficiency,only a little theoretical results have been established on the numerical... Although the isogeometric collocation(IGA-C)method has been successfully utilized in practical applications due to its simplicity and efficiency,only a little theoretical results have been established on the numerical analysis of the IGA-C method.In this paper,we deduce the convergence rate of the consistency of the IGA-C method.Moreover,based on the formula of the convergence rate,the necessary and sufficient condition for the consistency of the IGA-C method is developed.These results advance the numerical analysis of the IGA-C method. 展开更多
关键词 isogeometric collocation CONSISTENCY necessary and sufficient condition convergence rate
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A NEW SUFFICIENT CONDITION FOR SPARSE RECOVERY WITH MULTIPLE ORTHOGONAL LEAST SQUARES
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作者 Haifeng LI Jing ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2022年第3期941-956,共16页
A greedy algorithm used for the recovery of sparse signals,multiple orthogonal least squares(MOLS)have recently attracted quite a big of attention.In this paper,we consider the number of iterations required for the MO... A greedy algorithm used for the recovery of sparse signals,multiple orthogonal least squares(MOLS)have recently attracted quite a big of attention.In this paper,we consider the number of iterations required for the MOLS algorithm for recovery of a K-sparse signal x∈R^(n).We show that MOLS provides stable reconstruction of all K-sparse signals x from y=Ax+w in|6K/ M|iterations when the matrix A satisfies the restricted isometry property(RIP)with isometry constantδ_(7K)≤0.094.Compared with the existing results,our sufficient condition is not related to the sparsity level K. 展开更多
关键词 Sparse signal recovery multiple orthogonal least squares(MOLS) sufficient condition restricted isometry property(RIP)
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SUFFICIENT AND NECESSARY CONDITIONS ON THE EXISTENCE AND ESTIMATES OF BOUNDARY BLOW-UP SOLUTIONS FOR SINGULAR p-LAPLACIAN EQUATIONS
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作者 张学梅 阚士坤 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1175-1194,共20页
Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we pro... Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we provide sufficient and necessary conditions on the existence of boundary blow-up solutions to the p-Laplacian problem△_(p)u=b(x)g(u)for x∈Ω,u(x)→+∞as dist(x,■Ω)→0.The estimates of such solutions are also investigated.Moreover,when b has strong singularity,the nonexistence of boundary blow-up(radial)solutions and infinitely many radial solutions are also considered. 展开更多
关键词 singular p-Laplacian equation boundary blow-up sub-supersolution method EXISTENCE nonexistence and estimates sufficient and necessary conditions
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