期刊文献+
共找到18篇文章
< 1 >
每页显示 20 50 100
Motion and Special Relativity in Complex Spaces
1
作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第1期330-361,共32页
A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<... A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<sup>4</sup> space-time. As the [signed] absolute values of complex coordinates of the underlying motion’s characterization in C<sup>4</sup> one obtains a Newtonian-like type of motion whereas as the real parts of the complex motion’s description and of the complex Lorentz transformation, all the SR theory as modeled by M<sup>4</sup> real space-time can be recovered. This means all the SR theory is preserved in the real subspace M<sup>4</sup> of the space-time C<sup>4</sup> while becoming simpler and clearer in the new complex model’s framework. Since velocities in the complex model can be determined geometrically, with no primary use of time, time turns out to be definable within the equivalent theory of the reduced complex C<sup>4</sup> model to the C<sup>3</sup> “para-space” model. That procedure allows us to separate time from the (para)space and consider all the SR theory as a theory of C<sup>3</sup> alone. On the other hand, the complex time defined within the C<sup>3</sup> theory is interpreted and modeled by the single separate C<sup>1</sup> complex plane. The possibility for application of the C<sup>3</sup> model to quantum mechanics is suggested. As such, the model C<sup>3</sup> seems to have unifying abilities for application to different physical theories. 展开更多
关键词 Special Relativity Complex space and Time Models and Dramatic SR Simplification Complex Time and space Separation Complex Time Interpretation
下载PDF
Theoretical Models of Space and Its Philosophical Category
2
作者 Leonid Tchertov 《Journal of Philosophy Study》 2022年第4期185-202,共18页
Diverse concepts of space developed in history of natural philosophy,mathematics,physics,and other natural or cultural studies form theoretical models of spatial relations,given in human’s experience.Their diversity ... Diverse concepts of space developed in history of natural philosophy,mathematics,physics,and other natural or cultural studies form theoretical models of spatial relations,given in human’s experience.Their diversity is due not only to the multiplicity of philosophical and methodological approaches to the concept of space,but also to the variety of ways,in which spatial relationships can be organized.This variety gives a possibility to distinct autonomous spaces of different types with diverse sets of properties as well as separate spaces with their own ordinal,metrical,and sequential structures.Particularly,various ways of space semiotization in culture generate different types of autonomous and separate spaces:written texts,maps,pictures,chessboards,etc.In the same time,all particular notions of space are included in a general logical class.Its volume and content are covered by the philosophical category of space.Such general category cannot be reduced to mathematical,physical,or other concepts of space elaborated in particular sciences,however,it serves as a philosophical basis for their comparison. 展开更多
关键词 spatial relations autonomous and separate spaces VARIETY theoretical model philosophical category
下载PDF
Spaces with σ-point-discrete N_0-weak bases 被引量:1
3
作者 SHEN Rong-xin LIN Shou 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第1期116-126,共11页
It is discussed in this paper the spaces with σ-point-discrete N_0-weak bases. The main results are: (1) A space X has a σ-compact-finite N_0-weak base if and only if X is a k-space with a σ-point-discrete N_0-w... It is discussed in this paper the spaces with σ-point-discrete N_0-weak bases. The main results are: (1) A space X has a σ-compact-finite N_0-weak base if and only if X is a k-space with a σ-point-discrete N_0-weak base; (2) Under (CH), every separable space with a σ-point-discrete N_0-weak base has a countable N_0-weak base. 展开更多
关键词 N_0-weak base σ-point-discrete network σ-compact-finite network separable space.
下载PDF
THE BALL-COVERING PROPERTY ON DUAL SPACES AND BANACH SEQUENCE SPACES
4
作者 Shaoqiang SHANG 《Acta Mathematica Scientia》 SCIE CSCD 2021年第2期461-474,共14页
In this paper,we prove that(X,p)is separable if and only if there exists a w^(*)-lower semicontinuous norm sequence{p_(n)}_(n=1)^(∞)of(X^(*),p)such that(1)there exists a dense subset G_(n)of X^(*)such that p_(n)is Ga... In this paper,we prove that(X,p)is separable if and only if there exists a w^(*)-lower semicontinuous norm sequence{p_(n)}_(n=1)^(∞)of(X^(*),p)such that(1)there exists a dense subset G_(n)of X^(*)such that p_(n)is Gateaux differentiable on G_(n)and dp_(n)(Gn_(n))■X for all n∈N;(2)p_(n)≤p and p_(n)→p uniformly on each bounded subset of X^(*);(3)for anyα∈(0,1),there exists a ball-covering{B(x^(*)i,n,Ti,n)}∞i=1 of(X^(*),p_(n))such that it isα-off the origin and x_(i,n)^(*)∈Gn_(n).Moreover,we also prove that if Xi is a Gateaux differentiability space,then there exist a real numberα>0 and a ball-covering(B)i of Xi such that(B)i isα-off the origin if and only if there exist a real numberα>0 and a ball-covering B of l^(∞)(X_(i))such that(B)isα-off the origin. 展开更多
关键词 Ball-covering property separable space Gateaux differentiable point weak^(*)exposed point
下载PDF
SOME PROBLEMS IN THE Z-C-X SPACE
5
作者 朱传喜 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第8期942-947,共6页
The new concepts of the Z-C-X space and excellent cone are introduced. Some problems of random semiclosed 1-set-contractive operator are investigated in the Z-C-X space. At first, an important inequality is proved. Se... The new concepts of the Z-C-X space and excellent cone are introduced. Some problems of random semiclosed 1-set-contractive operator are investigated in the Z-C-X space. At first, an important inequality is proved. Secondly, several new conclusions are proved by means of random fixed point index in the theory of random topological degree. A random solution of a class of random operator equations under conditions of imitating the parallelogram law is obtained, famous Altman's theorem is generalized in partially ordered Z-C-X space. Therefore, some new results are obtained. 展开更多
关键词 Z-C-X space separable real Banach space random semiclosed 1-set-contractive operator random solution random continuous operator
下载PDF
Model-based Predictive Control for Spatially-distributed Systems Using Dimensional Reduction Models 被引量:3
6
作者 Meng-Ling Wang Ning Li Shao-Yuan Li 《International Journal of Automation and computing》 EI 2011年第1期1-7,共7页
In this paper, a low-dimensional multiple-input and multiple-output (MIMO) model predictive control (MPC) configuration is presented for partial differential equation (PDE) unknown spatially-distributed systems ... In this paper, a low-dimensional multiple-input and multiple-output (MIMO) model predictive control (MPC) configuration is presented for partial differential equation (PDE) unknown spatially-distributed systems (SDSs). First, the dimension reduction with principal component analysis (PCA) is used to transform the high-dimensional spatio-temporal data into a low-dimensional time domain. The MPC strategy is proposed based on the online correction low-dimensional models, where the state of the system at a previous time is used to correct the output of low-dimensional models. Sufficient conditions for closed-loop stability are presented and proven. Simulations demonstrate the accuracy and efficiency of the proposed methodologies. 展开更多
关键词 Spatially-distributed system principal component analysis (PCA) time/space separation dimension reduction model predictive control (MPC).
下载PDF
SOME RESULTS RELATED TO THE SEPARABLE QUOTIENT PROBLEM
7
作者 钟怀杰 《Acta Mathematica Scientia》 SCIE CSCD 1996年第3期248-256,共9页
The problem whether every infinite dimensional Banach space has an infinite dimensional separable quotient space has remained unsolved for a long time. In this paper we prove: the Banach space X has an infinite dimens... The problem whether every infinite dimensional Banach space has an infinite dimensional separable quotient space has remained unsolved for a long time. In this paper we prove: the Banach space X has an infinite dimensional separable quotient if and only if X has an infinite dimensional separable quasicomplemented subspace, also if and only if there exists a Banach space Y and a bounded linear operator T is an element of B(Y,X such that the range of T is nonclosed and dense in X. Besides, the other relevant questions for such spaces e.g. the question on operator ideals that on H.I.(hereditarily indecomposable) spaces, that on invariant subspaces of operators, etc, are also discussed. 展开更多
关键词 Banach space separable space quotient space bounded linear operator
下载PDF
Almost sure T-stability and convergence for random iterative algorithms
8
作者 张石生 王雄瑞 +1 位作者 刘敏 朱浸华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第6期805-810,共6页
The purpose of this paper is to study the almost sure T-stability and convergence of Ishikawa-type and Mann-type random iterative algorithms for some kind of C-weakly contractive type random operators in a separable B... The purpose of this paper is to study the almost sure T-stability and convergence of Ishikawa-type and Mann-type random iterative algorithms for some kind of C-weakly contractive type random operators in a separable Banach space. Under suitable conditions, the Bochner integrability of random fixed points for this kind of random operators and the almost sure T-stability and convergence for these two kinds of random iterative algorithms are proved. 展开更多
关键词 almost sure T-stability separable Banach space Bochner integrability Ishikawa-type random iterative scheme Mann-type random iterative scheme
下载PDF
On the Laws of Large Numbers for Double Arrays of Independent Random Elements in Banach Spaces 被引量:1
9
作者 Andrew ROSALSKY Le Van THANH Nguyen Thi THUY 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2014年第8期1353-1364,共12页
For a double array of independent random elements {Vmn,m ≥ 1,n ≥ 1} in a real separable Banach space,conditions are provided under which the weak and strong laws of large numbers for the double sums mi=1 nj=1Vij,m ... For a double array of independent random elements {Vmn,m ≥ 1,n ≥ 1} in a real separable Banach space,conditions are provided under which the weak and strong laws of large numbers for the double sums mi=1 nj=1Vij,m ≥ 1,n ≥ 1 are equivalent.Both the identically distributed and the nonidentically distributed cases are treated.In the main theorems,no assumptions are made concerning the geometry of the underlying Banach space.These theorems are applied to obtain Kolmogorov,Brunk–Chung,and Marcinkiewicz–Zygmund type strong laws of large numbers for double sums in Rademacher type p(1 ≤ p ≤ 2) Banach spaces. 展开更多
关键词 Real separable Banach space double array of independent random elements strong and weak laws of large numbers almost sure convergence convergence in probability Rademacher type p Banach space
原文传递
Embedding Cross-Dimensional Vector Space into ℓ^(2)
10
作者 XUE Shengli ZHANG Lijun +2 位作者 XIE Zhiqi YAN Weijun ZHANG Kuize 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2023年第6期2309-2324,共16页
The cross-dimensional dynamical systems have received increasing research attention in recent years.This paper characterizes the structure features of the cross-dimensional vector space.Specifically,it is proved that ... The cross-dimensional dynamical systems have received increasing research attention in recent years.This paper characterizes the structure features of the cross-dimensional vector space.Specifically,it is proved that the completion of cross-dimensional vector space is an infinite-dimensional separable Hilbert space.Hence,it means that one can isometrically and linearly embed the crossdimensional vector space into theℓ^(2),which is known as the space of square summable sequences.This result will be helpful in the modeling and analyzing the dynamics of cross-dimensional dynamical systems. 展开更多
关键词 Cross-dimensional vector space ℓ^(2)space semi-tensor product separable Hilbert space V-equivalence
原文传递
ICA Based Speckle Filtering for Target Extraction in SAR Images Using Adaptive Space Separation
11
作者 李昱彤 周越 杨磊 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第5期528-532,共5页
A novel approach based on independent component analysis (ICA) for speckle filtering and target extraction of synthetic aperture radar (SAR) images is proposed using adaptive space separation with weighted information... A novel approach based on independent component analysis (ICA) for speckle filtering and target extraction of synthetic aperture radar (SAR) images is proposed using adaptive space separation with weighted information entropy (WIE) incorporated. First the basis and the independent components are respectively obtained by ICA technique, and WIE of the image is computed; then based on the threshold computed from function T-WIE (threshold versus weighted-information-entropy), independent components are adaptively separated and the bases are classified accordingly. Thus, the image space is separated into two subspaces: "clean" and "noise". Then, a proposed nonlinear operator ABO is applied on each component of the 'clean' subspace for further optimization. Finally, recovery image is obtained reconstructing this subspace and target is easily extracted with binarisation. Note that here T-WIE is an interpolated function based on several representative target SAR images using proposed space separation algorithm. 展开更多
关键词 target extraction speckle filtering synthetic aperture radar (SAR) independent component analysis (ICA) adaptive space separation weighted information entropy (WIE)
原文传递
Preload relaxation analysis and reliable life prediction of space connection and separation device based on accelerated degradation tests
12
作者 Gen LIU Qiong WU +2 位作者 Zhihua WANG Yixin LUO Yufeng QI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第3期202-211,共10页
The safety and reliability of space connection and separation device has become a key issue due to the increasing service span of deep space exploration mission.The long-term preload relaxation(a key failure mode)of c... The safety and reliability of space connection and separation device has become a key issue due to the increasing service span of deep space exploration mission.The long-term preload relaxation(a key failure mode)of connection and separation devices is focused in this paper.A series of tests have been designed and implemented to investigate the preload relaxation regulation and a comprehensive method has been constructed to analyze and predict the reliable lifetime of the device.The two-stage preload relaxation law of the device is found and reasonably considered.Due to the different relaxation mechanism,the first-stage preload relaxation is assessed based on the working-condition test results,and the second-stage preload relaxation is characterized by accelerated test results.Finally,the service reliability and reliable life are evaluated.The experiment and assessment results demonstrate the reasonability and effectiveness of the proposed method which can achieve long-service reliability analysis for space connection and separation device within limited time. 展开更多
关键词 Accelerated degradation tests Life prediction Preload relaxation Reliability-analysis space connection and separation device
原文传递
A New Calculation Method of the Axial and Radial Velocity and Grade──Efficiency for High──Efficiency Cyclones
13
作者 Zhang Congzhi Wang Zijie (Shandong Architectural and Civil Engineering Institute) 《Journal of Thermal Science》 SCIE EI CAS CSCD 1995年第2期85-93,共9页
At present in China, the cyclones are widely used in the dust removal ventilation system of boilers, industry furnaces or pits etc., because of their simple structure, long life and cost efficiency. In order to improv... At present in China, the cyclones are widely used in the dust removal ventilation system of boilers, industry furnaces or pits etc., because of their simple structure, long life and cost efficiency. In order to improve efficiency of the cyclones, new theoretical calculation method is very important. In this paper, the concept of down-flow quantity is introduced and new formula is deducted based on Kilven law and the work has done by Zhao Weizhong[1]. The formula is not only of advantage theoretically but also fit with experimental results quite well. On the basis, the effect of three-dimensional velocity distribution in the flow field within cyclones and other parameters on the grade-efficiency calculation are analyzed and a new equation for grade-efficiency estimation is introduced. The calculating accuracy of the equation is better than the others theoretically and experimentally. 展开更多
关键词 CYCLONE axial velocity radial velocity grade-efficiency effective separate space.
原文传递
Analytical solution methods for eigenbuckling of symmetric cross-ply composite laminates 被引量:1
14
作者 Xing Yufeng Xiang Wei 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第1期282-291,共10页
Based on the first-order shear deformation theory, this paper explores the analytical methods for eigenbuckling of symmetric cross-ply rectangular composite laminates with a pair of parallel edges simply supported and... Based on the first-order shear deformation theory, this paper explores the analytical methods for eigenbuckling of symmetric cross-ply rectangular composite laminates with a pair of parallel edges simply supported and the remaining two edges arbitrarily constrained. The main contribution of present paper lies in two aspects: one is to present a simple and effective analytical method, namely, the separation-of-variables method, which can generate the closed-form buckling solutions without any computational difficulty; the other is to incorporate the accurate computation method of exponential matrix into the state space technique to avoid the inevitable numerically illconditioned problems reported in several literatures. The results obtained via both analytical methods are identical, and a good agreement with their counterparts in literature is observed. The separation-of-variables method can generate exact solutions within 1 s, which is impossible if the state space method is employed. Besides, the combination of the accurate computation method of exponential matrix and the state space method greatly improves the computational efficiency and gives correct results compared with the straightforward use of state space method. 展开更多
关键词 Accurate computation Analytical solution Composite laminates Eigenbuckling Separation of variablesState space
原文传递
A Schwarz Lemma at the Boundary of Hilbert Balls
15
作者 Zhihua CHEN Yang LIU Yifei PAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2018年第4期695-704,共10页
In this paper, the authors prove a general Schwarz lemma at the boundary for the holomorphic mapping f between unit balls B and B' in separable complex Hilbert spaces H and H', respectively. It is found that if the ... In this paper, the authors prove a general Schwarz lemma at the boundary for the holomorphic mapping f between unit balls B and B' in separable complex Hilbert spaces H and H', respectively. It is found that if the mapping f ∈ C^1+α at z0 ∈ B with f(zo) = wo ∈ OB', then the Fr&het derivative operator Df(z0) maps the tangent space Tz0( B^n) to Tw0( B'), the holomorphic tangent space Tz0^(1,0) to Tw0(1,0)( B'),respectively. 展开更多
关键词 Boundary Schwarz lemma Separable Hilbert space Holomorphic mapping Unit ball
原文传递
LINEAR ISOMETRIC NON-ANTICIPATIVETRANSFORMATIONS OF WIENER PROCESS
16
作者 ZORAN IVKOVIC DRAZEN PANTIC 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2000年第1期109-114,共6页
The necessary and sufficient conditions are given so that a non-anticipative transformation in Hilbert space is isometric. In terms of second order Wiener process, these conditions assure that a non-anticipative trans... The necessary and sufficient conditions are given so that a non-anticipative transformation in Hilbert space is isometric. In terms of second order Wiener process, these conditions assure that a non-anticipative transformation of Wiener process is a Wiener process, too. 展开更多
关键词 Resolution of identity Separable Hilbert space Wide sense Wiener process Non-anticipative transformation
原文传递
A Note on Card(X)
17
作者 Weituo Dai Meng Wang Limin Sun 《Analysis in Theory and Applications》 CSCD 2020年第4期468-481,共14页
The main interests here are to study the relationship between card(X)and card(P(X))and the connection between the separability of a space X and cardinality of some function space on it.We will convert the calculation ... The main interests here are to study the relationship between card(X)and card(P(X))and the connection between the separability of a space X and cardinality of some function space on it.We will convert the calculation of card(P(X))to the calculation of card(F(X!Q)).The main tool we used here is Zorn Lemma. 展开更多
关键词 CARDINALITY separability of space Zorn Lemma.
原文传递
Some Random Coincidence Point Theorems
18
作者 Ghulam Mustafa 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2003年第3期413-421,共9页
A class of multifunctions satisfying more general contractive inequalities is introduced and random coincidence point theorems for pairs of measurable nmltifunctions belonging to this class are proved.
关键词 separable metric space MULTIFUNCTIONS random coincidence point.
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部