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Multiple Shock Fronts for Hyperbolic Conservation Laws in Higher Dimensional Space
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作者 Wang Yaguang Department of Applied Mathematics Shanghai Jiao Tong University Shanghai,200030 China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1995年第1期88-104,共17页
The local existence of multiple shock fronts for hyperbolic conservation laws in higher dimensional space is established under the assumption that its frozen problem produces multiple uniformly stable planar shock fro... The local existence of multiple shock fronts for hyperbolic conservation laws in higher dimensional space is established under the assumption that its frozen problem produces multiple uniformly stable planar shock fronts. 展开更多
关键词 LAWS Multiple Shock Fronts for Hyperbolic Conservation Laws in Higher dimensional space 几几 MATH
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The Loeb Space of Denumerable Infinite Dimensional Probability Product Measure Spaces 被引量:2
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作者 陈东立 《Northeastern Mathematical Journal》 CSCD 2003年第3期249-253,共5页
Let {(Xi, Si, μi) : i ℃ N} be a sequence of probability measure spaces and (*Xi, L(*Si), L(*μi)) be the Loeb measure space with respect to (Xi, Si, μi) for i ℃ N. Let X =× Xi, S = ×Si,μ = ×μi. We... Let {(Xi, Si, μi) : i ℃ N} be a sequence of probability measure spaces and (*Xi, L(*Si), L(*μi)) be the Loeb measure space with respect to (Xi, Si, μi) for i ℃ N. Let X =× Xi, S = ×Si,μ = ×μi. We prove that × L(*Si) CL(*S) and in embedding meaning. 展开更多
关键词 denumerable infinite dimensional product measure space Loeb measure space internal set external set
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Variable dimensional state space based global path planning for mobile robot 被引量:1
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作者 张浩杰 陈慧岩 +6 位作者 姜岩 龚建伟 熊光明 陈慧岩 姜岩 龚建伟 熊光明 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期328-335,共8页
A variable dimensional state space(VDSS) has been proposed to improve the re-planning time when the robotic systems operate in large unknown environments.VDSS is constructed by uniforming lattice state space and gri... A variable dimensional state space(VDSS) has been proposed to improve the re-planning time when the robotic systems operate in large unknown environments.VDSS is constructed by uniforming lattice state space and grid state space.In VDSS,the lattice state space is only used to construct search space in the local area which is a small circle area near the robot,and grid state space elsewhere.We have tested VDSS with up to 80 indoor and outdoor maps in simulation and on segbot robot platform.Through the simulation and segbot robot experiments,it shows that exploring on VDSS is significantly faster than exploring on lattice state space by Anytime Dynamic A*(AD*) planner and VDSS is feasible to be used on robotic systems. 展开更多
关键词 variable dimensional state space lattice state space Anytime Dynamic A*(AD*) path planning
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COARSE ISOMETRIES BETWEEN FINITE DIMENSIONAL BANACH SPACES
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作者 孙玉奇 张文 《Acta Mathematica Scientia》 SCIE CSCD 2021年第5期1493-1502,共10页
Assume that X and Y are real Banach spaces with the same finite dimension.In this paper we show that if a standard coarse isometry f:X→Y satisfies an integral convergence condition or weak stability on a basis,then t... Assume that X and Y are real Banach spaces with the same finite dimension.In this paper we show that if a standard coarse isometry f:X→Y satisfies an integral convergence condition or weak stability on a basis,then there exists a surjective linear isometry U:X→Y such that∥f(x)−Ux∥=o(∥x∥)as∥x∥→∞.This is a generalization about the result of Lindenstrauss and Szankowski on the same finite dimensional Banach spaces without the assumption of surjectivity.As a consequence,we also obtain a stability result forε-isometries which was established by Dilworth. 展开更多
关键词 coarse isometry linear isometry finite dimensional Banach spaces
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k-MAJOR ORDER IN REAL INFINITE-DIMENSIONAL LINEAR SPACE AND ITS APPLICATION
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作者 Lu JingkuiDept.of Basic Knowledge,Shanghai Light Industry College,Shanghai 2 0 0 4 33. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2000年第3期302-306,共5页
In this paper,the k major cone and strict k major cone in real infinite dimensional linear space are introduced,through which the k major order is defined,and their properties are also discussed.Therefore,with the ... In this paper,the k major cone and strict k major cone in real infinite dimensional linear space are introduced,through which the k major order is defined,and their properties are also discussed.Therefore,with the help of them any two elements in real infinite dimensional linear space can be compared. 展开更多
关键词 Real infinite dimensional linear space k major cone k major order.
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The Effects of Space Dimension and Temperature on the Cross Mating of Three Cryptic Species of the Bemisia tabaci Complex in China
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作者 LI Xiao-xi LI Shao-jian +4 位作者 XUE Xia Muhammad Z Ahmed REN Shun-xiang Andrew G S Cuthbertson QIU Bao-li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第2期197-205,共9页
The sweetpotato whitefly Bemisia tabaci(Homoptera:Aleyrodidae)is a destructive pest of agriculture and horticulture worldwide.Recent phylogenetic analysis using mitochondrial cytochrome oxidase 1 sequences indicate... The sweetpotato whitefly Bemisia tabaci(Homoptera:Aleyrodidae)is a destructive pest of agriculture and horticulture worldwide.Recent phylogenetic analysis using mitochondrial cytochrome oxidase 1 sequences indicates that this whitefly is a species complex including at least 24 morphologically indistinguishable but genetically distinct cryptic species.In this study,the inter-species crosses of Middle East-Asia Minor 1(MEAM1),Mediterranean(MED)and Asia II 7 cryptic species,which were referred to as B,Q and Cv biotypes before,were conducted in two different devices,leaf cages(7 cm3)and cylinder cages(280 cm3),and at three temperatures of 22,30 and 38°C.Results indicated that no female progeny were produced in the reciprocal cross between MEAM1×Asia II 7,between MED×Asia II 7 cryptic species neither in leaf cage nor in cylinder cages,while 0.81 and 1.37% of females in the offspring were recorded in the reciprocal cross between MEAM1×MED in leaf cage experiments.Approximately 0.95-0.98% female progeny were recorded in the reciprocal cross between MEAM1×MED at 30°C,0.77% female progeny were recorded in the single cross direction between MEAM1 × MED at 22°C,and no female progeny were found in their reciprocal cross at 38°C in leaf cage.Our findings indicated that neither space dimension nor temperature have a significant effect on the hybridization of different B.tabaci cryptic species. 展开更多
关键词 Bemisia tabaci cross mating cryptic species reproductive isolation space dimension temperature
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PIECEWISE SMOOTH SOLUTION OF THE FIRST ORDER SEMILINEAR HYPERBOLIC SYSTEMS IN HIGHER SPACE DIMENSION
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作者 金树泽 《Acta Mathematica Scientia》 SCIE CSCD 1992年第2期190-202,共13页
It is important to study the propagation and interaction of progressing waves of nonlinear equations in the class of piecewise smooth function. However, there has not been many works on that in multidimensional case. ... It is important to study the propagation and interaction of progressing waves of nonlinear equations in the class of piecewise smooth function. However, there has not been many works on that in multidimensional case. In 1985, J, Rauch & M. Reed have provad the existence and uniqueness of piecewise smooth solution for 展开更多
关键词 PIECEWISE SMOOTH SOLUTION OF THE FIRST ORDER SEMILINEAR HYPERBOLIC SYSTEMS IN HIGHER space DIMENSION der
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A Model of the Universe that Can Explain Dark Matter, Dark Energy, and the Fourth Space Dimension
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作者 Donald J. Koterwas 《Journal of Modern Physics》 2016年第10期1247-1276,共31页
This paper explains how a model of the universe can be constructed by incorporating time and space into geometry in a unique way to produce a 4-space dimension/1-time dimension model. The model can then show how dark ... This paper explains how a model of the universe can be constructed by incorporating time and space into geometry in a unique way to produce a 4-space dimension/1-time dimension model. The model can then show how dark matter can be the gravity that is produced by real matter that exists throughout our entire universe. The model can also show how dark energy is not an increase in energy that is causing the accelerated expansion of the universe, but is an accelerating decrease in matter throughout the universe as the stars and galaxies in the universe continue to convert matter into energy during their life cycles. And then the model can show how a fourth space dimension must exist in our universe to locate a point in space. 展开更多
关键词 UNIVERSE Dark Matter Dark Energy Gravity Fourth space Dimension
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A Comparative Study on Two Techniques of Reducing the Dimension of Text Feature Space
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作者 Yin Zhonghang, Wang Yongcheng, Cai Wei & Diao Qian School of Electronic & Information Technology, Shanghai Jiaotong University, Shanghai 200030, P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第1期87-92,共6页
With the development of large scale text processing, the dimension of text feature space has become larger and larger, which has added a lot of difficulties to natural language processing. How to reduce the dimension... With the development of large scale text processing, the dimension of text feature space has become larger and larger, which has added a lot of difficulties to natural language processing. How to reduce the dimension has become a practical problem in the field. Here we present two clustering methods, i.e. concept association and concept abstract, to achieve the goal. The first refers to the keyword clustering based on the co occurrence of 展开更多
关键词 in the same text and the second refers to that in the same category. Then we compare the difference between them. Our experiment results show that they are efficient to reduce the dimension of text feature space. Keywords: Text data mining
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A Creation Model from the Gell-Mann Standard Model to the Creation of Bio Cells: Based on the Assumption of Homogeneous 5D Space-Time Universe
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作者 Kai Wai Wong Wan Ki Chow 《Journal of Modern Physics》 2020年第7期1058-1074,共17页
In this paper, we briefly go over the homogeneous 5D model field theory: from the 5D space-time inception, to its quantum field solutions given in terms of Higgs vacuum, filled with magnetic monopole bose fields of al... In this paper, we briefly go over the homogeneous 5D model field theory: from the 5D space-time inception, to its quantum field solutions given in terms of Higgs vacuum, filled with magnetic monopole bose fields of all energies. Then through the space dimension reduction projections, the Gell-Mann standard model was obtained as well as a quantum to Classical connection was made via introducing Bose distribution to the monopoles to obtain the Perelman entropy and Ricci Flow mappings. This provided us a picture to the creation of Astronomical objects, from galaxies to stars and planets. This method of splitting the monopole energy into ranges is extended to show that below the basic rest mass range of the electron and Quark, it still can be applied to explaining for the creation of the chemical elements periodic table. But perhaps the most interesting is in the lowest hundreds of Hz energy range, obtained from yet another 3 fold space symmetry breaking, into 2D × 1D, producing bio nitrogenous bases composed of 3 Carbon 12 in hexagon structures, due to preservation of the 1D monopole standing waves of this low frequencies. From that by imposing gauge changes the monopole states into DNA spectra. Since such spectra states retain the DLRO, it induces formation of charge carriers periodicity in a spherical bio cell.. It was then argued that due to cell’s surface proteins, the structure must contain partial filled VB, with “p” state hole density, and empty CB, separated from VB by a positive band gap. Such band structures resemble known HTC Cuprate ceramics. Since the HTC goes through a Superconductivity transition via the simultaneous bose exciton condensation, providing a Coulomb pressure, which reduces the band gap substantially, and induces the ODLRO transition of the hole density. The same obviously applies to the bio cells. Because of the near continuous exciton levels generated, a matching to the DNA spectra then can always occur by selective choices of proteins on the cell surface. Judging from a numerical study, we did years ago on YBCO, with doping. We found with a large enough VB hole density, the exciton induced superconducting gap can easily lead to <em>T</em><em>c</em> in the room temperature range. In fact by EMF excitation can increase the exciton pressure and trigger the ODLRO transition <em>T</em><em>c</em> upward. In fact, numerical results then suggest there do exist coherent EMF spectra from three key elements: Water, Carbon and Hydrogen, together with Oxygen, as studied over the years by numerous people, starting from Schr<span style="white-space:nowrap;">&ouml;</span>dinger to most recently Geesink. 展开更多
关键词 5D Fermat’s Theorem space Dimension Reduction Projections Perelman Mappings The Higgs Vacuum: A B.E. Condensed Monopole Bosons Realization of Excitonic Induced Superconducting “p” Valence Band Orbitals in Bio Cells The Final Coherent Building Block EMF Spectra: Water Carbon Hydrogen and Oxygen
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The Maximum Dissipative Extension of Schrodinger Operator
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作者 田立新 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第10期973-980,共8页
In the present paper we study the maximum dissipative extension of Schrodingeroperator.introduce the generalized indefinite metvic space and get the representation ofmaximum dissipative extension of Schrodinger operat... In the present paper we study the maximum dissipative extension of Schrodingeroperator.introduce the generalized indefinite metvic space and get the representation ofmaximum dissipative extension of Schrodinger operator in natural boundary space.make preparation for the further study longtime chaotic behaxior of infinite dimensiondynamics system in nonlinear Schrodinger equation. 展开更多
关键词 infinite dimension dynamics system. nonlinear Schfrodingerequation. indefinite metric space. dissipative operator
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Global Existence of Small Solutions for Cubic Quasi-linear Klein-Gordon Systems in One Space Dimension 被引量:2
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作者 Dao Yuan FANG Ru Ying XUE 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第4期1085-1102,共18页
In this paper, we consider a system of two cubic quasi-linear Klein-Gordon equations with different masses for small, smooth, compactly supported Cauchy data in one space dimension. We show that such a system has glob... In this paper, we consider a system of two cubic quasi-linear Klein-Gordon equations with different masses for small, smooth, compactly supported Cauchy data in one space dimension. We show that such a system has global existence when the nonlinearities satisfy a convenient null condition. Our results extend the global existence proved by Sunagawa recently under the non-resonance assumption to that under the resonance assumption. 展开更多
关键词 Cubic Quasi-linear Klein-Gordon systems One space dimension Global existence Asymptotic behavior
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Variable-fidelity optimization with design space reduction 被引量:2
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作者 Mohammad Kashif Zahir Gao Zhenghong 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第4期841-849,共9页
Advanced engineering systems, like aircraft, are defined by tens or even hundreds of design variables. Building an accurate surrogate model for use in such high-dimensional optimization problems is a difficult task ow... Advanced engineering systems, like aircraft, are defined by tens or even hundreds of design variables. Building an accurate surrogate model for use in such high-dimensional optimization problems is a difficult task owing to the curse of dimensionality. This paper presents a new algorithm to reduce the size of a design space to a smaller region of interest allowing a more accurate surrogate model to be generated. The framework requires a set of models of different physical or numerical fidelities. The low-fidelity (LF) model provides physics-based approximation of the high-fidelity (HF) model at a fraction of the computational cost. It is also instrumental in identifying the small region of interest in the design space that encloses the high-fidelity optimum. A surrogate model is then constructed to match the low-fidelity model to the high-fidelity model in the identified region of interest. The optimization process is managed by an update strategy to prevent convergence to false optima. The algorithm is applied on mathematical problems and a two-dimen-sional aerodynamic shape optimization problem in a variable-fidelity context. Results obtained are in excellent agreement with high-fidelity results, even with lower-fidelity flow solvers, while showing up to 39% time savings. 展开更多
关键词 Airfoil optimization Curse of dimensionality Design space reduction Genetic algorithms Kriging Surrogate models Surrogate update strategies Variable fidelity
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