期刊文献+
共找到1,044篇文章
< 1 2 53 >
每页显示 20 50 100
Discontinuous bifurcation and coexistence of attractors in a piecewise linear map with a gap 被引量:5
1
作者 屈世显 卢永智 +1 位作者 张林 何大韧 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第12期4418-4423,共6页
Coexistence of attractors with striking characteristics is observed in this work, where a stable period-5 attractor coexists successively with chaotic band-ll, period-6, chaotic band-12 and band-6 attractors. They are... Coexistence of attractors with striking characteristics is observed in this work, where a stable period-5 attractor coexists successively with chaotic band-ll, period-6, chaotic band-12 and band-6 attractors. They are induced by dif- ferent mechanisms due to the interaction between the discontinuity and the non-invertibility. A characteristic boundary collision bifurcation, is observed. The critical conditions are obtained both analytically and numerically. 展开更多
关键词 coexistence of attractors piecewise linear map mapping hole discontinuous bifurcation
原文传递
Noise destroys the coexistence of periodic orbits of a piecewise linear map 被引量:1
2
作者 王参军 杨科利 屈世显 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期205-208,共4页
The effects of Gaussian white noise and Gaussian colored noise on the periodic orbits of period-5(P-5) and period-6(P-6) in their coexisting domain of a piecewise linear map are investigated numerically.The probab... The effects of Gaussian white noise and Gaussian colored noise on the periodic orbits of period-5(P-5) and period-6(P-6) in their coexisting domain of a piecewise linear map are investigated numerically.The probability densities of some orbits are calculated.When the noise intensity is D = 0.0001,only the orbits of P-5 exist,and the coexisting phenomenon is destroyed.On the other hand,the self-correlation time τ of the colored noise also affects the coexisting phenomenon.When τc〈τ〈τc,only the orbits of P-5 appear,and the stability of the orbits of P-5 is enhanced.However,when τ〉τc(τc and τc are critical values),only the orbits of P-6 exist,and the stability of the P-6 orbits is enhanced greatly.When τ〈τc,the orbits of P-5 and P-6 coexist,but the stability of the P-5 orbits is enhanced and that of P-6 is weakened with τ increasing. 展开更多
关键词 piecewise linear map noise periodic orbit
原文传递
Linear Maps Preserving Idempotency of Products of Matrices on Upper Triangular Matrix Algebras
3
作者 QI JING Ji GUO-XING 《Communications in Mathematical Research》 CSCD 2009年第3期253-264,共12页
Let Tn be the algebra of all n × n complex upper triangular matrices. We give the concrete forms of linear injective maps on Tn which preserve the nonzero idempotency of either products of two matrices or triple ... Let Tn be the algebra of all n × n complex upper triangular matrices. We give the concrete forms of linear injective maps on Tn which preserve the nonzero idempotency of either products of two matrices or triple Jordan products of two matrices. 展开更多
关键词 linear map MATRIX IDEMPOTENT product of two matrices triple Jordan product of two matrices
在线阅读 下载PDF
Linear Maps Preserving Projections of Jordan Products on the Space of Self-Adjoint Operators
4
作者 Meifeng WANG Guoxing JI 《Journal of Mathematical Research with Applications》 CSCD 2012年第2期235-240,共6页
Let Bs (7-/) be the real linear space of all self-adjoint operators on a complex Hilbert spae 7-/ with dimT/〉 2. It is proved that a linear surjective map on Bs(T/) preserves the nonzero projections of Jordan pro... Let Bs (7-/) be the real linear space of all self-adjoint operators on a complex Hilbert spae 7-/ with dimT/〉 2. It is proved that a linear surjective map on Bs(T/) preserves the nonzero projections of Jordan products of two operators if and only if there is a unitary or an anti-unitary operator U on T/such that ^(X) = AU*XU, VX E Bs(TI) for some constant ~ with k E {1,-1}. 展开更多
关键词 self-adjoint operator Jordan product PROJECTION linear map.
原文传递
Galois linear maps and their construction
5
作者 Gu Yue Wang Wei Wang Shuanhong 《Journal of Southeast University(English Edition)》 EI CAS 2019年第4期522-526,共5页
The condition of an algebra to be a Hopf algebra or a Hopf(co)quasigroup can be determined by the properties of Galois linear maps.For a bialgebra H,if it is unital and associative as an algebra and counital coassocia... The condition of an algebra to be a Hopf algebra or a Hopf(co)quasigroup can be determined by the properties of Galois linear maps.For a bialgebra H,if it is unital and associative as an algebra and counital coassociative as a coalgebra,then the Galois linear maps T1 and T2 can be defined.For such a bialgebra H,it is a Hopf algebra if and only if T1 is bijective.Moreover,T1^-1 is a right H-module map and a left H-comodule map(similar to T2).On the other hand,for a unital algebra(no need to be associative),and a counital coassociative coalgebra A,if the coproduct and counit are both algebra morphisms,then the sufficient and necessary condition of A to be a Hopf quasigroup is that T1 is bijective,and T1^-1 is left compatible with ΔT1-11^r and right compatible with mT1-1^l at the same time(The properties are similar to T2).Furthermore,as a corollary,the quasigroups case is also considered. 展开更多
关键词 Galois linear map ANTIPODE Hopf algebra Hopf(co)quasigroup
在线阅读 下载PDF
An Adaptive Non-Linear Map and Its Application
6
作者 YAN Xuefeng 《Wuhan University Journal of Natural Sciences》 CAS 2006年第3期572-576,共5页
A novel adaptive non-linear mapping (ANLM), integrating an adaptive mapping error (AME) with a chaosgenetic algorithm (CGA) including chaotic variable, was proposed to overcome the deficiencies of non-linear map... A novel adaptive non-linear mapping (ANLM), integrating an adaptive mapping error (AME) with a chaosgenetic algorithm (CGA) including chaotic variable, was proposed to overcome the deficiencies of non-linear mapping (NLM). The value of AME weight factor is determined according to the relative deviation square of distance between the two mapping points and the corresponding original objects distance. The larger the relative deviation square between two distances is, the larger the value of the corresponding weight factor is. Due to chaotic mapping operator, the evolutional process of CGA makes the individuals of subgenerations distributed ergodieally in the defined space and circumvents the premature of the individuals of subgenerations. The comparison results demonstrated that the whole performance of CGA is better than that of traditional genetic algorithm. Furthermore, a typical example of mapping eight-dimenslonal olive oil samples onto two-dimensional plane was employed to verify the effectiveness of ANLM. The results showed that the topology-preserving map obtained by ANLM can well represent the classification of original objects and is much better than that obtained by NLM. 展开更多
关键词 adaptive non-linear map topology- preserving mapping error chaotic variable genetic algorithm cluster
在线阅读 下载PDF
Non-linear Maps on Borel Subalgebras of Simple Lie Algebras Preserving Abelin Ideals
7
作者 赵延霞 王登银 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第4期615-623,共9页
Let g be a complex simple Lie algebra of rank ι, b the standard Borel subalgebra. An invertible map on Ь is said to preserve abelian ideals if it maps each abelian ideal to some such ideal of the same dimension. In ... Let g be a complex simple Lie algebra of rank ι, b the standard Borel subalgebra. An invertible map on Ь is said to preserve abelian ideals if it maps each abelian ideal to some such ideal of the same dimension. In this article, by using some results of Chevalley groups, the theory of root systems and root space decomposition, the author gives an explicit description on such maps of Ь. 展开更多
关键词 simple Lie algebra abelian ideal non-linear map
在线阅读 下载PDF
On Representations Associated with Completely n-Positive Linear Maps on Pro-C^*-Algebras 被引量:2
8
作者 Maria JOITA 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2008年第1期55-64,共10页
It is shown that an n × n matrix of continuous linear maps from a pro-C^*-algebra A to L(H), which verifies the condition of complete positivity, is of the form [V^*TijФ(·)V]^n i,where Ф is a represe... It is shown that an n × n matrix of continuous linear maps from a pro-C^*-algebra A to L(H), which verifies the condition of complete positivity, is of the form [V^*TijФ(·)V]^n i,where Ф is a representation of A on a Hilbert space K, V is a bounded linear operator from H to K, and j=1,[Tij]^n i,j=1 is a positive element in the C^*-algebra of all n×n matrices over the commutant of Ф(A) in L(K). This generalizes a result of C. Y.Suen in Proc. Amer. Math. Soc., 112(3), 1991, 709-712. Also, a covariant version of this construction is given. 展开更多
关键词 Pro-C^*-Algebra Completely n-positive linear maps Covariant completely n-positive linear maps
原文传递
Similarity-Invariant Subspaces and Similarity-Preserving Linear Maps 被引量:4
9
作者 Guo Xing JI Hong Ke DU Department of Mathematics, Shaanxi Normal University. Xian 710062. P. R. China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2002年第3期489-498,共10页
In this paper, the similarity-invariant subspaces of B(H), which is tile Banach algebra of all bounded linear operators on a separable infinite-dimensional Hilbert space H, are completely characterized and the represe... In this paper, the similarity-invariant subspaces of B(H), which is tile Banach algebra of all bounded linear operators on a separable infinite-dimensional Hilbert space H, are completely characterized and the representations of bounded linear maps on B(H) which preserve similarity in both directions are given. 展开更多
关键词 linear operator Similarity-invariant subspace Similarity-preserving linear map
原文传递
Inverse-preserving Linear Maps Between Spaces of Matrices over Fields 被引量:3
10
作者 Xian ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第3期873-878,共6页
Suppose F is a field different from F2, the field with two elements. Let Mn(F) and Sn(F) be the space of n × n full matrices and the space of n ×n symmetric matrices over F, respectively. For any G1, G2 ... Suppose F is a field different from F2, the field with two elements. Let Mn(F) and Sn(F) be the space of n × n full matrices and the space of n ×n symmetric matrices over F, respectively. For any G1, G2 ∈ {Sn(F), Mn(F)}, we say that a linear map f from G1 to G2 is inverse-preserving if f(X)^-1 = f(X^-1) for every invertible X ∈ G1. Let L (G1, G2) denote the set of all inverse-preserving linear maps from G1 to G2. In this paper the sets .L(Sn(F),Mn(F)), L(Sn(F),Sn(F)), L (Mn(F),Mn(F)) and L(Mn (F), Sn (F)) are characterized. 展开更多
关键词 Field Inverse-preserving linear map Space of full matrices Space of symmetric matrices
原文传递
LMM:A Fixed-Point Linear Mapping Based Approximate Multiplier for IoT
11
作者 吴莹 温晨怡 +1 位作者 尹勋钊 卓成 《Journal of Computer Science & Technology》 SCIE EI CSCD 2023年第2期298-308,共11页
The development of IoT(Internet of Things)calls for circuit designs with energy and area efficiency for edge devices.Approximate computing which trades unnecessary computation precision for hardware cost savings is a ... The development of IoT(Internet of Things)calls for circuit designs with energy and area efficiency for edge devices.Approximate computing which trades unnecessary computation precision for hardware cost savings is a promising direction for error-tolerant applications.Multipliers,as frequently invoked basic modules which consume non-trivial hardware costs,have been introduced approximation to achieve distinct energy and area savings for data-intensive applications.In this paper,we propose a fixed-point approximate multiplier that employs a linear mapping technique,which enables the configurability of approximation levels and the unbiasedness of computation errors.We then introduce a dynamic truncation method into the proposed multiplier design to cover a wider and more fine-grained configuration range of approximation for more flexible hardware cost savings.In addition,a novel normalization module is proposed for the required shifting operations,which balances the occupied area and the critical path delay compared with normal shifters.The introduced errors of our proposed design are analyzed and expressed by formulas which are validated by experimental results.Experimental evaluations show that compared with accurate multipliers,our proposed approximate multiplier design provides maximum area and power savings up to 49.70%and 66.39%respectively with acceptable computation errors. 展开更多
关键词 approximate computing FIXED-POINT linear mapping MULTIPLIER Internet of Things(IoT)
原文传递
New Developments on Operator Reverse AM-GM Inequality for Positive Linear Maps
12
作者 Shazia KARIM Ilyas ALI Muhammad MUSHTAQ 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2022年第2期419-430,共12页
In this research article,we shall give some reverse Arithmetic-Geometric mean inequalities for unital positive linear maps on Hilbert space operators under some different conditions.Our results are sharper and more pr... In this research article,we shall give some reverse Arithmetic-Geometric mean inequalities for unital positive linear maps on Hilbert space operators under some different conditions.Our results are sharper and more precise as compared to some recent published results.Moreover,we shall present refinements of the Lin conjecture. 展开更多
关键词 Positive operators unital positive linear maps operator AM-GM inequality operator reverse AM-GM inequality operator norm
原文传递
A NEW SIMPLE 2-D PIECEWISE LINEAR MAP
13
作者 Zeraoulia ELHADJ Julien Clinton SPROTT 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2010年第2期379-389,共11页
A new simple piecewise linear map of the plane is presented and analyzed, then a detailed study of its dynamical behaviour is described, along with some other dynamical phenomena, especially fixed points and their sta... A new simple piecewise linear map of the plane is presented and analyzed, then a detailed study of its dynamical behaviour is described, along with some other dynamical phenomena, especially fixed points and their stability, observation of a new chaotic attractors obtained via border collision bifurcation. An important resuk about coexisting chaotic attractors is also numerically studied and discussed. 展开更多
关键词 Border collision bifurcation new chaotic attractor piecewise linear map.
原文传递
Non-linear Invertible Maps that Preserve Staircase Subalgebras
14
作者 ZHAO YAN-XIA XIA YU-LING 《Communications in Mathematical Research》 CSCD 2012年第3期265-274,共10页
Let g be the general linear Lie algebra consisting of all n x n matrices over a field F and with the usual bracket operation {x, y} =xy - yx. An invertible map φ : g →g is said to preserve staircase subalgebras if ... Let g be the general linear Lie algebra consisting of all n x n matrices over a field F and with the usual bracket operation {x, y} =xy - yx. An invertible map φ : g →g is said to preserve staircase subalgebras if it maps every staircase subalgebra to some staircase subalgebra of the same dimension. In this paper, we devote to giving an explicit description on the invertible maps on g that preserve staircase subalgebras. 展开更多
关键词 general linear Lie algebra staircase subalgebra non-linear map
在线阅读 下载PDF
LINEAR DILATATION OF QUASIREGULAR MAPPINGS IN SPACE 被引量:2
15
作者 陈克应 《Acta Mathematica Scientia》 SCIE CSCD 2001年第2期213-220,共8页
This paper presents an explicit upper bound for the linear dilatation of K- quasiregular (K-qr) mappings, which improves S. Rickman's [6, P.37] corresponding re- sult for K-qr mappings and generalizes P. Seittenra... This paper presents an explicit upper bound for the linear dilatation of K- quasiregular (K-qr) mappings, which improves S. Rickman's [6, P.37] corresponding re- sult for K-qr mappings and generalizes P. Seittenranta's [7, Theorem 1.5] result for K- quasiconformal (K-qc) maps. 展开更多
关键词 K-qr mapping K-qc map linear dilatation local index MODULUS normal domain
在线阅读 下载PDF
Solution of Nonlinear Advection-Diffusion Equations via Linear Fractional Map Type Nonlinear QCA 被引量:1
16
作者 Shinji Hamada Hideo Sekino 《Journal of Quantum Information Science》 2016年第4期263-295,共33页
Linear fractional map type (LFMT) nonlinear QCA (NLQCA), one of the simplest reversible NLQCA is studied analytically as well as numerically. Linear advection equation or Time Dependent Schr&ouml;dinger Equation (... Linear fractional map type (LFMT) nonlinear QCA (NLQCA), one of the simplest reversible NLQCA is studied analytically as well as numerically. Linear advection equation or Time Dependent Schr&ouml;dinger Equation (TDSE) is obtained from the continuum limit of linear QCA. Similarly it is found that some nonlinear advection-diffusion equations including inviscid Burgers equation and porous-medium equation are obtained from LFMT NLQCA. 展开更多
关键词 Nonlinear Quantum Cellular Automaton QCA Quantum Walk linear Fractional map Advection-Diffusion Equation Burgers Equation Porous-Medium Equation SOLITON
在线阅读 下载PDF
Linear-fitting-based similarity coefficient map for tissue dissimilarity analysis in T2^*-w magnetic resonance imaging
17
作者 余绍德 伍世宾 +5 位作者 王浩宇 魏新华 陈鑫 潘万龙 Hu Jiani 谢耀钦 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期610-615,共6页
Similarity coefficient mapping(SCM) aims to improve the morphological evaluation of T*2weighted magnetic resonance imaging(T*2-w MRI). However, how to interpret the generated SCM map is still pending. Moreover, ... Similarity coefficient mapping(SCM) aims to improve the morphological evaluation of T*2weighted magnetic resonance imaging(T*2-w MRI). However, how to interpret the generated SCM map is still pending. Moreover, is it probable to extract tissue dissimilarity messages based on the theory behind SCM? The primary purpose of this paper is to address these two questions. First, the theory of SCM was interpreted from the perspective of linear fitting. Then, a term was embedded for tissue dissimilarity information. Finally, our method was validated with sixteen human brain image series from multiecho T*2-w MRI. Generated maps were investigated from signal-to-noise ratio(SNR) and perceived visual quality, and then interpreted from intra- and inter-tissue intensity. Experimental results show that both perceptibility of anatomical structures and tissue contrast are improved. More importantly, tissue similarity or dissimilarity can be quantified and cross-validated from pixel intensity analysis. This method benefits image enhancement, tissue classification, malformation detection and morphological evaluation. 展开更多
关键词 T*2-w magnetic resonance imaging similarity coefficient map linear fitting tissue dissimilarity
原文传递
Dissipative Properties of ω-Order Preserving Partial Contraction Mapping in Semigroup of Linear Operator
18
作者 Akinola Yussuff Akinyele Kamilu Rauf +1 位作者 Aasa Moses Adebowale Omosowon Jude Babatunde 《Advances in Pure Mathematics》 2019年第6期544-550,共7页
This paper consists of dissipative properties and results of dissipation on infinitesimal generator of a C0-semigroup of ω-order preserving partial contraction mapping (ω-OCPn) in semigroup of linear operator. The p... This paper consists of dissipative properties and results of dissipation on infinitesimal generator of a C0-semigroup of ω-order preserving partial contraction mapping (ω-OCPn) in semigroup of linear operator. The purpose of this paper is to establish some dissipative properties on ω-OCPn which have been obtained in the various theorems (research results) and were proved. 展开更多
关键词 SEMIGROUP linear OPERATOR DISSIPATIVE OPERATOR CONTRACTION mapping and RESOLVENT
在线阅读 下载PDF
Non-Linear Effects in Optical Systems by Lie Algebra and Symplectic Mapping
19
作者 Víctor M. Castañ o 《Journal of Modern Physics》 CAS 2022年第11期1314-1323,共10页
The use of signals of different frequencies determines the geometrical deviation with respect to the optical axes of a given beam. This angle can be determined by Sympletic Map (SM), a powerful and simple mathematical... The use of signals of different frequencies determines the geometrical deviation with respect to the optical axes of a given beam. This angle can be determined by Sympletic Map (SM), a powerful and simple mathematical tool for the characterization and construction of images in Geometrical Optics. The Sympletic Map constitutes a Lie Group, with an algebra associated: the Lie Algebra. In general, the SM can be expressed as an infinite series, where each term corresponds to different contributions produced by the optical devices that constitute the optical system (lenses, apertures, bandwidth cutoff, etc.). The level of correction to be performed on the image to recover the original object is clear and controllable by SM. This formalism can be extended easily to physical optics to describe diffraction and interference phenomena. 展开更多
关键词 Symplectic mapping Geometrical Optics Non-linear Effects
在线阅读 下载PDF
结构拓扑优化ICM方法的B映射求解途径
20
作者 彭细荣 隋允康 +1 位作者 叶红玲 铁军 《固体力学学报》 北大核心 2025年第2期162-176,共15页
本文基于结构拓扑优化的ICM(独立、连续和映射的简称)方法,发展出了双映射接力运作的求解途径,因“双”的英文简称为B,故称之为B-ICM求解途径.该途径由两步组成:第一步是L(线性)映射作用于结构拓扑优化问题,使之成为离散模型,然后构造... 本文基于结构拓扑优化的ICM(独立、连续和映射的简称)方法,发展出了双映射接力运作的求解途径,因“双”的英文简称为B,故称之为B-ICM求解途径.该途径由两步组成:第一步是L(线性)映射作用于结构拓扑优化问题,使之成为离散模型,然后构造了约束函数;第二步是NL(非线性)映射作用于离散模型,使之成为连续模型,同时实现了单元拓扑变量由离散到连续的转换过程.以往ICM方法的求解途径中,上述第一步只是起到理论推导的作用,构造约束函数同其它建模与求解等算法均包含在第二步里,因此属于“一步求解”途径.B-ICM虽然属于“两步求解”途径,但是优化模型寻优仍然沿用ICM方法惯用的序列对偶二次规划算法.本文以位移约束的体积极小化结构拓扑优化问题为例,示例了上述建模及求解过程.单载荷工况和多载荷工况的算例,均印证了本文的研究实现了预期构想,与目前旨在得到清晰拓扑的3种方法(1、考虑Heaviside投影的SIMP方法;2、浮动投影拓扑优化<简称为FPTO>方法;3、非惩罚的光滑边界材料分布拓扑优化<简称为SEMDOT>方法),以及ICM方法以往的求解途径,进行了迭代次数、清晰程度、寻优能力等方面的对比,结果表明B-ICM求解途径表现最好.本文研究不仅丰富了ICM方法建模策略,推动了ICM方法求解途径的完善,也为解决模糊边界问题提供了一种优越的做法.过往的连续体结构拓扑优化求解,因消除棋盘格和网格依赖性问题而采取的过滤操作导致最优拓扑构型产生模糊边界,而且过滤半径越大,则边界越模糊.本文克服了这些令人堪忧的问题,可以成功地得到最优拓扑构型的清晰边界.值得提及的是,本文研究的关键技术,可以移植到包括变密度方法等所有连续变量优化的方法中. 展开更多
关键词 结构拓扑优化 ICM方法 两步求解途径 线性映射 非线性映射 位移约束的体积极小化问题
原文传递
上一页 1 2 53 下一页 到第
使用帮助 返回顶部