期刊文献+
共找到14篇文章
< 1 >
每页显示 20 50 100
Comparison of two kinds of approximate proximal point algorithms for monotone variational inequalities
1
作者 陶敏 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期537-540,共4页
This paper proposes two kinds of approximate proximal point algorithms (APPA) for monotone variational inequalities, both of which can be viewed as two extended versions of Solodov and Svaiter's APPA in the paper ... This paper proposes two kinds of approximate proximal point algorithms (APPA) for monotone variational inequalities, both of which can be viewed as two extended versions of Solodov and Svaiter's APPA in the paper "Error bounds for proximal point subproblems and associated inexact proximal point algorithms" published in 2000. They are both prediction- correction methods which use the same inexactness restriction; the only difference is that they use different search directions in the correction steps. This paper also chooses an optimal step size in the two versions of the APPA to improve the profit at each iteration. Analysis also shows that the two APPAs are globally convergent under appropriate assumptions, and we can expect algorithm 2 to get more progress in every iteration than algorithm 1. Numerical experiments indicate that algorithm 2 is more efficient than algorithm 1 with the same correction step size, 展开更多
关键词 monotone variational inequality approximate proximate point algorithm inexactness criterion
在线阅读 下载PDF
Research on the reliability of motion accuracy for ammunition conveyor in artillery automatic loading system
2
作者 Guangsong Chen Junhua Chen +1 位作者 Jinsong Tang Yongji Liu 《Chinese Journal of Mechanical Engineering》 2026年第1期102-114,共13页
The automatic loading systems of artillery are critical for the accurate,efficient,and reliable delivery of pro-jectiles and propellants into the gun chamber.In modern artillery,the ammunition conveyor serves as the e... The automatic loading systems of artillery are critical for the accurate,efficient,and reliable delivery of pro-jectiles and propellants into the gun chamber.In modern artillery,the ammunition conveyor serves as the end effector of the automatic loading system,and its motion state significantly impacts the accuracy of projectiles.Therefore,it is of immense importance to precisely and effectively evaluate the reliability of the motion accuracy of the ammunition conveyor.This paper aims to propose a practical and efficient analysis method for evaluating the reliability of the motion accuracy of the ammunition conveyor.The proposed approach involves the use of a deep learning network to approximate the physical model and the extremum method to obtain a single cycle sequence decoupling strategy for solving the time-varying reliability issue of complex systems.Employing this strategy,the time-varying reliability of the ammunition conveyor is transformed into a static reliability problem.The proposed method includes the use of a deep feedforward neural network,second-order saddle point ap-proximation(SPA)method,extremum method,and efficient global optimization(EGO)technology.The results reveal that the reliability of the motion accuracy of the ammunition conveyor is 93.42%,with the maximum failure probability occurring at 0.21 s.These results serve as an important reference for the structural optimi-zation design of the ammunition conveyor based on reliability and the maintenance of the operational process. 展开更多
关键词 Automatic loading system Ammunition conveyor Motion accuracy RELIABILITY Second-order saddle point approximation
在线阅读 下载PDF
MODIFIED APPROXIMATE PROXIMAL POINT ALGORITHMS FOR FINDING ROOTS OF MAXIMAL MONOTONE OPERATORS
3
作者 曾六川 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第3期293-301,共9页
In order to find roots of maximal monotone operators, this paper introduces and studies the modified approximate proximal point algorithm with an error sequence {e k} such that || ek || \leqslant hk || xk - [(x)\tilde... In order to find roots of maximal monotone operators, this paper introduces and studies the modified approximate proximal point algorithm with an error sequence {e k} such that || ek || \leqslant hk || xk - [(x)\tilde]k ||\left\| { e^k } \right\| \leqslant \eta _k \left\| { x^k - \tilde x^k } \right\| with ?k = 0¥ ( hk - 1 ) < + ¥\sum\limits_{k = 0}^\infty {\left( {\eta _k - 1} \right)} and infk \geqslant 0 hk = m\geqslant 1\mathop {\inf }\limits_{k \geqslant 0} \eta _k = \mu \geqslant 1 . Here, the restrictions on {η k} are very different from the ones on {η k}, given by He et al (Science in China Ser. A, 2002, 32 (11): 1026–1032.) that supk \geqslant 0 hk = v < 1\mathop {\sup }\limits_{k \geqslant 0} \eta _k = v . Moreover, the characteristic conditions of the convergence of the modified approximate proximal point algorithm are presented by virtue of the new technique very different from the ones given by He et al. 展开更多
关键词 modified approximate proximal point algorithm maximal monotone operator CONVERGENCE
在线阅读 下载PDF
Multi-Interval-Aggregation Failure Point Approximation for Remaining Useful Life Prediction
4
作者 Linchuan Fan Xiaolong Chen +1 位作者 Shuo Li Yi Chai 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期639-641,共3页
Dear Editor,This letter focuses on the remaining useful life(RUL)prediction task under limited labeled samples.Existing machine-learning-based RUL prediction methods for this task usually pay attention to mining degra... Dear Editor,This letter focuses on the remaining useful life(RUL)prediction task under limited labeled samples.Existing machine-learning-based RUL prediction methods for this task usually pay attention to mining degradation information to improve the prediction accuracy of degradation value or health indicator for the next epoch.However,they ignore the cumulative prediction error caused by iterations before reaching the failure point. 展开更多
关键词 remaining useful life prediction failure point degradation value health indicator multi interval aggregation failure point approximation machine learning based mining degradation information
在线阅读 下载PDF
On p-ω-hyponormal Operators 被引量:3
5
作者 YANGChang-sen LIHai-ying 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第1期79-84,共6页
In this paper, we show that if T is p-ω-hyponormal, the nonzero points of the approximate and joint approximate point spectrum of T are identical; Moreover, we obtain a pair of inequalities similar to p-ω-hyponormal... In this paper, we show that if T is p-ω-hyponormal, the nonzero points of the approximate and joint approximate point spectrum of T are identical; Moreover, we obtain a pair of inequalities similar to p-ω-hyponormal operators. 展开更多
关键词 Furuta inequality Lowner-Heinz inequality approximate point spectrum p-ω-hyponormal operators
在线阅读 下载PDF
A NOTE ON n-PERINORMAL OPERATORS 被引量:1
6
作者 左红亮 左飞 《Acta Mathematica Scientia》 SCIE CSCD 2014年第1期194-198,共5页
The study of operators satisfying σja(T ) = σa(T ) is of significant interest. Does σja(T ) = σa(T ) for n-perinormal operator T ∈ B(H)? This question was raised by Mecheri and Braha [Oper. Matrices 6 ... The study of operators satisfying σja(T ) = σa(T ) is of significant interest. Does σja(T ) = σa(T ) for n-perinormal operator T ∈ B(H)? This question was raised by Mecheri and Braha [Oper. Matrices 6 (2012), 725-734]. In the note we construct a counterexample to this question and obtain the following result: if T is a n-perinormal operator in B(H), then σja(T )/{0} = σa(T )/{0}. We also consider tensor product of n-perinormal operators. 展开更多
关键词 n-perinormal operators approximate point spectrum joint approximatepoint spectrum tensor product
在线阅读 下载PDF
FIXED POINT THEOREMS AND BEST APPROXIMATION IN CONVEX METRIC SPACES 被引量:2
7
作者 I.Beg N.Shahzad M.Iqbal 《Analysis in Theory and Applications》 1992年第4期97-105,共9页
Results regarding best approximation and best Simultaneous approximation on convex metric spaces are Obtained.Existence of fixed points for an ultimately nonexpansive semigroup of mappings is also shown.
关键词 CIG FIXED POINT THEOREMS AND BEST APPROXIMATION IN CONVEX METRIC SPACES
在线阅读 下载PDF
BROWDER AND SEMI-BROWDER OPERATORS
8
作者 Fatma Fakhfakh Maher Mnif 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期942-954,共13页
In this article, we study characterization, stability, and spectral mapping the- orem for Browder's essential spectrum, Browder's essential defect spectrum and Browder's essential approximate point spectrum of clos... In this article, we study characterization, stability, and spectral mapping the- orem for Browder's essential spectrum, Browder's essential defect spectrum and Browder's essential approximate point spectrum of closed densely defined linear operators on Banach spaces. 展开更多
关键词 Browder and semi-Browder operators Browder's essential spectrum Browder's essential defect spectrum Browder's essential approximate point spectrum
在线阅读 下载PDF
Wave Period Distributions in Non-Gaussian Mixed Sea States
9
作者 王迎光 《China Ocean Engineering》 SCIE EI CSCD 2013年第6期809-820,共12页
The wave period probability densities in non-Gaussian mixed sea states are calculated by utilizing a transformed Gaussian process method. The transformation relating the non-Gaussian process and the original Gaussian ... The wave period probability densities in non-Gaussian mixed sea states are calculated by utilizing a transformed Gaussian process method. The transformation relating the non-Gaussian process and the original Gaussian process is obtained based on the equivalence of the level up-crossing rates of the two processes. A saddle point approximation procedure is applied for calculating the level up-crossing rates in this study. The accuracy and efficiency of the transformed Gaussian process method are validated by comparing the results predicted by using the method with those predicted by the Monte Carlo simulation method. 展开更多
关键词 wave period mixed sea state NON-GAUSSIAN saddle point approximation Monte Carlo simulation
在线阅读 下载PDF
The Properties of k-quasi-*-A(n) Operator
10
作者 zuo fei SHEN Jun-li 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期375-381,共7页
An operator T is called k-quasi-*-A(n) operator, if T^(*k)|T^(1+n)|^(2/(1+n))T^k ≥T^(*k)|T~* |~2T^k , k ∈ Z, which is a generalization of quasi-*-A(n) operator. In this paper we prove some properties of k-quasi-*-A(... An operator T is called k-quasi-*-A(n) operator, if T^(*k)|T^(1+n)|^(2/(1+n))T^k ≥T^(*k)|T~* |~2T^k , k ∈ Z, which is a generalization of quasi-*-A(n) operator. In this paper we prove some properties of k-quasi-*-A(n) operator, such as, if T is a k-quasi-*-A(n) operator and N(T )■N(T~* ), then its point spectrum and joint point spectrum are identical. Using these results, we also prove that if T is a k-quasi-*-A(n) operator and N(T )■N(T ), then the spectral mapping theorem holds for the Weyl spectrum and for the essential approximate point spectrum. 展开更多
关键词 k-quasi-*-A(n) operator QUASISIMILARITY single valued extension property Weyl spectrum essential approximate point spectrum
在线阅读 下载PDF
PROPERTIES OF p-ω-HYPONORMAL OPERATORS
11
作者 Yang Changsen Li Haiying 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第1期64-68,共5页
The approximate point spectrum properties of p-ω-hyponormal operators are given and proved. In faet, it is a generalization of approximate point speetrum properties of ω- hyponormal operators. The relation of spectr... The approximate point spectrum properties of p-ω-hyponormal operators are given and proved. In faet, it is a generalization of approximate point speetrum properties of ω- hyponormal operators. The relation of spectra and numerical range of p-ω-hyponormal operators is obtained, On the other hand, for p-ω-hyponormal operators T,it is showed that if Y is normal,then T is also normal. 展开更多
关键词 ω-hyponormal operators p-ω-hyponormal operator approximate point spectrum.
在线阅读 下载PDF
Finite Operators
12
作者 Hadia Messaoudene 《Journal of Mathematics and System Science》 2013年第4期190-194,共5页
Let H be a separable infinite dimensional complex Hilbert space, and L(H) the algebra of all bounded linear operators on 3-t'. The class of finite operators is the class of operators for which the distance of the i... Let H be a separable infinite dimensional complex Hilbert space, and L(H) the algebra of all bounded linear operators on 3-t'. The class of finite operators is the class of operators for which the distance of the identity operator I and the derivation range is maximal; where the derivation range of the operator A is defined by δA;δA : L(H) -L(H) X- AX - XA. In this paper we present some properties of finite operators and give some classes of operators which are in the class of finite operators, and find for witch condition A ~ W is a finite operator in L(2-H H), and gave a g6neralisation of Stampflli theorem. 展开更多
关键词 Finite operator IDENTITY class R1 reduced approximate point spectrum.
在线阅读 下载PDF
AN APPLICATION OF A FIXED POINT THEOREM TO BEST SIMULTANEOUS APPROXIMATION
13
作者 Isinat Beg Naseer Shahzad 《Analysis in Theory and Applications》 1994年第3期1-4,共4页
Using a recent result regarding the fixed points of multivalued mappings, the existence of invariant best simultaneous approximation in chainable metric space is proved.
关键词 AN APPLICATION OF A FIXED POINT THEOREM TO BEST SIMULTANEOUS APPROXIMATION
在线阅读 下载PDF
Iterative Schemes for a Family of Finite Asymptotically Pseudocontractive Mappings in Banach Spaces 被引量:1
14
作者 GU Feng 《Journal of Mathematical Research and Exposition》 CSCD 2009年第5期864-870,共7页
Let E be a real Banach space and K be a nonempty closed convex and bounded subset of E. Let Ti : K→ K, i=1, 2,... ,N, be N uniformly L-Lipschitzian, uniformly asymptotically regular with sequences {ε^(i)n} and as... Let E be a real Banach space and K be a nonempty closed convex and bounded subset of E. Let Ti : K→ K, i=1, 2,... ,N, be N uniformly L-Lipschitzian, uniformly asymptotically regular with sequences {ε^(i)n} and asymptotically pseudocontractive mappings with sequences {κ^(i)n}, where {κ^(i)n} and {ε^(i)n}, i = 1, 2,... ,N, satisfy certain mild conditions. Let a sequence {xn} be generated from x1 ∈ K by zn:= (1-μn)xn+μnT^nnxn, xn+1 := λnθnx1+ [1 - λn(1 + θn)]xn + λnT^nnzn for all integer n ≥ 1, where Tn = Tn(mod N), and {λn}, {θn} and {μn} are three real sequences in [0, 1] satisfying appropriate conditions. Then ||xn- Tixn||→ 0 as n→∞ for each l ∈ {1, 2,..., N}. The results presented in this paper generalize and improve the corresponding results of Chidume and Zegeye, Reinermann, Rhoades and Schu. 展开更多
关键词 approximated fixed point sequence uniformly asymptotically regular mapping asymptotically pseudocontractive mapping.
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部