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LARGE TIME ASYMPTOTIC BEHAVIOR OF THE COMPRESSIBLE NAVIER-STOKES EQUATIONS IN PARTIAL SPACE-PERIODIC DOMAINS
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作者 曹政子 尹会成 +1 位作者 张麟 朱露 《Acta Mathematica Scientia》 SCIE CSCD 2016年第4期1167-1191,共25页
In this article, we study the large time behavior of the 3-D isentropic compressible Navier-Stokes equation in the partial space-periodic domains, and simultaneously show that the related profile systems can be descri... In this article, we study the large time behavior of the 3-D isentropic compressible Navier-Stokes equation in the partial space-periodic domains, and simultaneously show that the related profile systems can be described by like Navier-Stokes equations with suitable "pressure" functions in lower dimensions. Our proofs are based on the energy methods together with some delicate analysis on the corresponding linearized problems. 展开更多
关键词 Large time behavior profile system energy method partial space-periodic domain Fourier series
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Libration and end body swing stabilization of a parallel partial space elevator system 被引量:2
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作者 Gefei SHI Gangqiang LI Zheng H.ZHU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第3期187-199,共13页
This paper studies the libration and stabilization of a parallel partial space elevator system in circular orbits. The system is made up of two paralleled partial space elevators, each of which consists of one main sa... This paper studies the libration and stabilization of a parallel partial space elevator system in circular orbits. The system is made up of two paralleled partial space elevators, each of which consists of one main satellite, one end body and a climber moving along the tether between them.The libration characteristics of the elevator are studied through numerical analysis by a new dynamic model, and a novel control strategy is proposed to stabilize the swing of the end body by projecting the climber speeds only. Optimal control method is used to implement the new control strategy in the case where the climbers move in opposite direction. The simulation results validate the effectiveness of the proposed control strategy whose application will neither sacrifice the transport efficiency nor exacerbate libration significantly. 展开更多
关键词 Libration stabilization Nonlinear dynamics Optimal control Parallel partial space elevator space tether
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Orbital radius keeping of floating partial space elevator in cargo transposition 被引量:1
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作者 Gefei Shi Zheng H.Zhu 《Astrodynamics》 CSCD 2023年第3期259-269,共11页
A floating partial space elevator(PSE)is a PSE with a floating main satellite.This work aims to keep the orbital radius of the main satellite of a floating PSE in cargo transposition without the use of thrusts.A six-d... A floating partial space elevator(PSE)is a PSE with a floating main satellite.This work aims to keep the orbital radius of the main satellite of a floating PSE in cargo transposition without the use of thrusts.A six-degree-of-freedom two-piece dumbbell model was built to analyze the dynamics of a floating PSE.By adjusting the climber’s moving speed and rolling of the end body,the main satellite’s orbital radius can be kept.A novel control strategy using a proportional shrinking horizon model predictive control law containing a self-stability modified law is proposed to stabilize both the orbital and libration states to regulate the speed of only the climber.Simulation results validated the proposed control strategy.The system provides a successful approach to the desired equilibrium by the end of the transposition. 展开更多
关键词 floating partial space elevator(PSE) self-stability modified law shrinking horizon model predictive control
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COMMON FIXED POINT OF GENERALIZED WEAKLY CONTRACTIVE MAPS IN PARTIAL METRIC SPACES 被引量:5
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作者 Vesna COJBAIC RAJIC Stojan RADENOVIC Sunny CHAUHAN 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1345-1356,共12页
In this paper, using the context of complete partial metric spaces, some common fixed point results of maps that satisfy the generalized (ψ, Ф)-weak contractive conditions are obtained. Our results generalize, ext... In this paper, using the context of complete partial metric spaces, some common fixed point results of maps that satisfy the generalized (ψ, Ф)-weak contractive conditions are obtained. Our results generalize, extend, unify, enrich and complement many existing results in the literature. Example are given showing the validaty of our results. 展开更多
关键词 Common fixed point lower semi-continuous function weak (ψ Ф)-contraction partial metric space
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Some questions on partial metric spaces 被引量:1
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作者 GE Xun LIN Shou 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2020年第4期392-398,共7页
We show that the completion of a partial metric space can fail be unique,which answers a question on completions of partial metric spaces.In addition,to this paper discusses metrizability around partial metric spaces.
关键词 partial metric space COMPLETION METRIZABILITY
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Fixed Point of Multivalued Operators on Partial Metric Spaces
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作者 P. Amiri Sh. Rezapour 《Analysis in Theory and Applications》 2013年第2期158-168,共11页
In this paper, we prove some results on fixed point of multivalued operators on partial metric spaces.
关键词 Fixed point multivalued operator partial metric space.
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NEWTON-LIK E METNODS IN PARTIALLY ORDERED BANACH SPACES
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作者 I.K.Argyros 《Analysis in Theory and Applications》 1993年第1期1-9,共9页
We provide convergence results and error estimates for Newton-like methods in generalized Banach spaces.The idea of a generalized norm is used whichis defined to be a map from a linear space into a partially ordered B... We provide convergence results and error estimates for Newton-like methods in generalized Banach spaces.The idea of a generalized norm is used whichis defined to be a map from a linear space into a partially ordered Banach space.Convergence results and error estimates are improved compared with the real norm theory. 展开更多
关键词 SHOW QZ NEWTON-LIK E METNODS IN partialLY ORDERED BANACH spaceS
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Study of Fixed Point Theorems for Higher Dimension in Partially Ordered Metric Spaces
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作者 Ibtisam Masmali Sumitra Dalal 《Applied Mathematics》 2016年第5期399-412,共14页
In this paper, we establish the existence and uniqueness of fixed points of operator , when n is an arbitrary positive integer and X is a partially ordered complete metric space. We have shown examples to verify our w... In this paper, we establish the existence and uniqueness of fixed points of operator , when n is an arbitrary positive integer and X is a partially ordered complete metric space. We have shown examples to verify our work. Our results generalize the recent fixed point theorems cited in [1]-[4] etc. and include several recent developments. 展开更多
关键词 n-Tupled Coincidence Points n-Tupled Coincidence Fixed Points Compatible Maps Fixed Points and partially Ordered Metric spaces
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Endpoints of Multi-Valued Weak Contractions on the Metric Space of Partially Ordered Groups
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作者 Congdian Cheng 《Advances in Pure Mathematics》 2022年第11期638-651,共14页
The present work considers the endpoint in the abstract metric space. It firstly introduces the metric space of partially ordered groups and the metric space of partially ordered modules, respectively;and defines the ... The present work considers the endpoint in the abstract metric space. It firstly introduces the metric space of partially ordered groups and the metric space of partially ordered modules, respectively;and defines the convergence of sequences and the multi-valued weak contractions, etc., on the introduced space. And then, with the methods of functional analysis and abstract algebra, it successively establishes an endpoint theorem for the metric space of partially ordered groups and an endpoint theorem for the metric space of partially ordered modules. The contributions of this article extend the theory of cone metric space constructed by Huang and Zhang (2007) and some recent results on the fixed point and endpoint theory, such as the endpoint theorem given by Amini-Harandi (2010). 展开更多
关键词 Fixed Point Endpoint Metric space Valued in partially Ordered Group Topological Structure Weak Contraction
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Some Fixed Point Results of Ciric-Type Contraction Mappings on Ordered <i>G</i>-Partial Metric Spaces
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作者 Johnson O. Olaleru Kanayo Stella Eke Hallowed O. Olaoluwa 《Applied Mathematics》 2014年第6期1004-1012,共9页
We introduce the concept of generalized quasi-contraction mappings in G-partial metric spaces and prove some fixed point results in ordered G-partial metric spaces. The results generalize and extend some recent result... We introduce the concept of generalized quasi-contraction mappings in G-partial metric spaces and prove some fixed point results in ordered G-partial metric spaces. The results generalize and extend some recent results in literature. 展开更多
关键词 Fixed Points Generalized Quasi-Contraction Maps Bounded Orbit partially ORDERED Set G-partial Metric spaces
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Simulation of Space Charge Impact on Partial Discharge Inception Voltage in Power Busbars Dedicated to Future Hybrid Aircrafts
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作者 Mallys Elliazar Banda David Malec Jean-Pascal Cambronne 《Circuits and Systems》 2018年第11期196-212,共17页
Reducing greenhouse gases, saving energy resources and mass optimization require technological changes towards increasingly electric vehicles. At the same time, performance improvement of semiconductor and dielectric ... Reducing greenhouse gases, saving energy resources and mass optimization require technological changes towards increasingly electric vehicles. At the same time, performance improvement of semiconductor and dielectric materials further promotes electronic components confinement, resulting in a significant increase of embedded power densities. In the particular case of future hybrid propulsion aircrafts, electrical power that intended to supply reactors would be converted through power electronics components mounted on power busbars and insulated by solid dielectrics materials. These dielectrics materials have to respond to various electrical constraints of use (HVDC), in spite of environment change of aircraft parameters such as low pressure, temperature and thermal cycles, humidity... Unfortunately, partial discharges phenomenon is the most problem within electrical insulation system (EIS). Based on a topological model of power busbars designed for power converters dedicated to hybrid aircraft, partial discharge studies were conducted by simulation in various charging conditions of a PTFE insulator. Simulation results, which focus on electric field thresholds criteria of partial discharge inception voltage in air, reveal a net sensitivity of a space charge accumulation and distribution on dielectrics behaviour even for low space charge density, depending on their location in dielectrics. Compared to the behaviour observed with implanted homocharges, when by increasing homocharges density from 0.5 C/m3 to 2 C/m3 we observe a decrease of electric field by 450%, simulation results show a highest risk of partial discharge inception when heterocharges are accumulated inside dielectrics. Their accumulation increases the electric field in triple points beyond electric field thresholds of partial discharge inception in air. The simulated electric field reaching 22 kV/mm with only 2 C/m3 of heterocharges density accumulated in dielectric/busbars interfaces. 展开更多
关键词 SIMULATION partial DISCHARGE space Charge POWER BUSBARS HYBRID Aircraft
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Theorems of Helly's Type for Partially-closed Half-spaces
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作者 Liu Jian-Guo Guo Qi 《Communications in Mathematical Research》 CSCD 2018年第2期117-124,共8页
In this article, under quite weaker conditions, theorems of Helly’s type for(not necessarily finite) family of partially closed half-spaces are presented in both analytic and geometric forms. Examples are also provid... In this article, under quite weaker conditions, theorems of Helly’s type for(not necessarily finite) family of partially closed half-spaces are presented in both analytic and geometric forms. Examples are also provided to show that these conditions cannot be omitted in general. 展开更多
关键词 Helly's theorem partially-closed half-space affine function convex set
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Partial Feedback Based Orthogonal Space-Time Block Coding With Flexible Feedback Bits
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作者 Lei Wang Zhigang Chen 《Communications and Network》 2013年第3期127-131,共5页
The conventional orthogonal space-time block code (OSTBC) with limited feedback has fixed p-1?feedback bits for the specific ntp?transmit antennas. A new partial feedback based OSTBC which provides flexible feedback b... The conventional orthogonal space-time block code (OSTBC) with limited feedback has fixed p-1?feedback bits for the specific ntp?transmit antennas. A new partial feedback based OSTBC which provides flexible feedback bits is proposed in this paper. The proposed scheme inherits the properties of having a simple decoder and the full diversity of OSTBC, moreover, preserves full data rate. Simulation results show that for?ntp transmit antennas, the proposed scheme has the similar performance with the conventional one by using p-1?feedback bits, whereas has the better performance with more feedback bits. 展开更多
关键词 MIMO Transmit DIVERSITY space-TIME Block CODING partial FEEDBACK
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Space Topologies and Their Dual Space Topologies for Conventional Functional Space Topologies
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作者 Mahjoub A. Elamin 《Journal of Applied Mathematics and Physics》 2024年第3期778-804,共27页
In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topo... In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topological vector spaces and it is in this context that we have chosen to present this work. We are interested in the topology of its spaces and in the topologies of their dual spaces. The first part, we presented the fundamental topological properties of topological vector spaces. The second part, we studied Frechet spaces and particularly the space S(R<sup>n</sup>) of functions of class C<sup>∞ </sup>on R<sup>n</sup> which are as well as all their rapidly decreasing partial derivatives. We have also studied its dual S'(Rn</sup>) the space of tempered distributions. The last part aims to define a topological structure on an increasing union of Frechet spaces called inductive limit of Frechet spaces. We study in particular the space D(Ω) of functions of class C<sup>∞</sup> with compact supports on Ω as well as its dual D' (Ω) the space distributions over the open set Ω. 展开更多
关键词 Linear Forms Dual spaces Frechet spaces partial Derivatives DISTRIBUTIONS Topological Structure Weak Topology Strong Topology
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Periodic Solutions in UMD Spaces for Some Neutral Partial Functional Differential Equations 被引量:1
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作者 Rachid Bahloul Khalil Ezzinbi Omar Sidki 《Advances in Pure Mathematics》 2016年第10期713-726,共15页
The aim of this work is to study the existence of a periodic solution for some neutral partial functional differential equations. Our approach is based on the R-boundedness of linear operators Lp-multipliers and UMD-s... The aim of this work is to study the existence of a periodic solution for some neutral partial functional differential equations. Our approach is based on the R-boundedness of linear operators Lp-multipliers and UMD-spaces. 展开更多
关键词 Neutral partial Functional Differential Equations Periodic Solutions R-BOUNDEDNESS Lp-Multipliers UMD spaces
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Common Fixed Point Results for Quasi-contractions Involving Altering Distance Functions in Ordered Cone Metric Spaces 被引量:1
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作者 SONG Ji-ping WANG Mao-fa 《Chinese Quarterly Journal of Mathematics》 2018年第1期1-16,共16页
Some common fixed point results for mappings satisfying a quasi-contractive condition which involves altering distance functions are obtained in partially ordered complete cone metric spaces. A sufficient condition fo... Some common fixed point results for mappings satisfying a quasi-contractive condition which involves altering distance functions are obtained in partially ordered complete cone metric spaces. A sufficient condition for the uniqueness of common fixed point is proved. Also, an example is given to support our results. 展开更多
关键词 partially ordered cone metric space quasi-contraction common fixed point altering distance function
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ITERATIVE SOLUTIONS FOR SYSTEMS OF NONLINEAR OPERATOR EQUATIONS IN BANACH SPACE 被引量:1
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作者 宋光兴 《Acta Mathematica Scientia》 SCIE CSCD 2003年第4期461-466,共6页
By using partial order method, the existence, uniqueness and iterative approximation of solutions for a class of systems of nonlinear operator equations in Banach space are discussed. The results obtained in this pape... By using partial order method, the existence, uniqueness and iterative approximation of solutions for a class of systems of nonlinear operator equations in Banach space are discussed. The results obtained in this paper extend and improve recent results. 展开更多
关键词 System of operator equations SOLUTION iterative technique cone and partial ordering banach space
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Adaptive functional link network control of near-space vehicles with dynamical uncertainties 被引量:5
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作者 Yanli Du Qingxian Wu Changsheng Jiang Jie Wen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第5期868-876,共9页
The control law design for a near-space hypersonic vehicle(NHV) is highly challenging due to its inherent nonlinearity,plant uncertainties and sensitivity to disturbances.This paper presents a novel functional link ... The control law design for a near-space hypersonic vehicle(NHV) is highly challenging due to its inherent nonlinearity,plant uncertainties and sensitivity to disturbances.This paper presents a novel functional link network(FLN) control method for an NHV with dynamical thrust and parameter uncertainties.The approach devises a new partially-feedback-functional-link-network(PFFLN) adaptive law and combines it with the nonlinear generalized predictive control(NGPC) algorithm.The PFFLN is employed for approximating uncertainties in flight.Its weights are online tuned based on Lyapunov stability theorem for the first time.The learning process does not need any offline training phase.Additionally,a robust controller with an adaptive gain is designed to offset the approximation error.Finally,simulation results show a satisfactory performance for the NHV attitude tracking,and also illustrate the controller's robustness. 展开更多
关键词 adaptive control system dynamical uncertainties partially feedback functional link network near-space vehicle.
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基于Partial EIV模型的空间平面拟合总体最小二乘法 被引量:1
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作者 曾昭福 《北京测绘》 2018年第6期697-700,共4页
针对空间平面拟合中系数矩阵含有部分误差的特点,根据Partial EIV模型提取系数矩阵随机元素的思想,将空间平面拟合模型系数矩阵中观测元素作为随机元素提取组成新的未知向量。采用Partial EIV模型线性化的新解法求解拟合参数,简化了计... 针对空间平面拟合中系数矩阵含有部分误差的特点,根据Partial EIV模型提取系数矩阵随机元素的思想,将空间平面拟合模型系数矩阵中观测元素作为随机元素提取组成新的未知向量。采用Partial EIV模型线性化的新解法求解拟合参数,简化了计算过程,且保证了系数矩阵相同元素的改正数一致,较EIV模型的总体最小二乘法,理论模型更加严谨。通过算例说明了,本文方法可以用于拟合空间平面,且精度有一定优势。 展开更多
关键词 空间平面拟合 partial EIV模型 总体最小二乘
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PARTIAL BOCHNER INTEGRABILITY (I)
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作者 陈泽乾 《Acta Mathematica Scientia》 SCIE CSCD 1999年第3期293-299,共7页
This paper is concerned with partial Bochner integrals with emphasis on a geometrical study of partial Bochner integrability. Convex sets involving the range of L-1-bounded functions are constructed. These constructio... This paper is concerned with partial Bochner integrals with emphasis on a geometrical study of partial Bochner integrability. Convex sets involving the range of L-1-bounded functions are constructed. These constructions provide a complete characterization of partial Bochner integrable functions. 展开更多
关键词 Banach space norming set partial Bochner integral
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