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Poisson theory of generalized Bikhoff equations 被引量:4
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作者 尚玫 梅凤翔 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3155-3157,共3页
This paper presents a Poisson theory of the generalized Birkhoff equations, including the algebraic structure of the equations, the sufficient and necessary condition on the integral and the conditions under which a n... This paper presents a Poisson theory of the generalized Birkhoff equations, including the algebraic structure of the equations, the sufficient and necessary condition on the integral and the conditions under which a new integral can be deduced by a known integral as well as the form of the new integral. 展开更多
关键词 generalized Birkhoff equations Poisson theory INTEGRALS
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Quantum Gravity Based on Generalized Thermodynamics
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作者 Sergei Yurievich Eremenko 《Journal of Applied Mathematics and Physics》 2023年第4期988-1028,共41页
This paper proposes a novel approach and simplified model of Quantum Gravity based on the unification framework of Generalized Thermodynamics which suggests cross-related terms and modified equations of General Relati... This paper proposes a novel approach and simplified model of Quantum Gravity based on the unification framework of Generalized Thermodynamics which suggests cross-related terms and modified equations of General Relativity and Quantum Mechanics. To address the “background problem”, a metric tensor is introduced into stationary Schrödinger equations via curved coordinates yielding quantum spacetime variation term. Then quantum Lagrangian is added to Einstein-Hilbert functional yielding quantum stress-energy tensor. Obtained from one variational principle, two theories are linked by a common quantum spacetime field. The theory offers some interpretations of the quantum vacuum spacetime fluctuations, zero-point-fields, quantum fields shifting towards high spacetime densities, the quantum nature of spacetime, and black hole singularity. 展开更多
关键词 Quantum Gravity general Relativity Quantum Spacetime generalized Thermodynamics Unified theory
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Semigroup of Weakly Continuous Operators Associated to a Generalized Schrödinger Equation
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作者 Yolanda Silvia Santiago Ayala 《Journal of Applied Mathematics and Physics》 2023年第4期1061-1076,共16页
In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger equation in the periodic distributional space P’. Furthermore, we prove that the solution depends continuously r... In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger equation in the periodic distributional space P’. Furthermore, we prove that the solution depends continuously respect to the initial data in P’. Introducing a family of weakly continuous operators, we prove that this family is a semigroup of operators in P’. Then, with this family of operators, we get a fine version of the existence and dependency continuous theorem obtained. Finally, we provide some consequences of this study. 展开更多
关键词 Semigroups theory Weakly Continuous Operators Existence of Solution generalized Schrödinger Equation Distributional Problem Periodic Distributional Space
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Group of Weakly Continuous Operators Associated to a Generalized Schrödinger Type Homogeneous Model
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作者 Yolanda Silvia Santiago Ayala 《Journal of Applied Mathematics and Physics》 2023年第4期919-932,共14页
In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger type homogeneous model in the periodic distributional space P’. Furthermore, we prove that the solution depends ... In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger type homogeneous model in the periodic distributional space P’. Furthermore, we prove that the solution depends continuously respect to the initial data in P’. Introducing a family of weakly continuous operators, we prove that this family is a group of operators in P’. Then, with this family of operators, we get a fine version of the existence and dependency continuous theorem obtained. Finally, we give some remarks derived from this study. 展开更多
关键词 Groups theory Weakly Continuous Operators Existence of Solution generalized Schrödinger Type Equation Homogeneous Equation Periodic Distributional Space
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GENERALIZED THEORY OF NONLINEAR AND UNSTEADY MECHANICS AND APPLICATIONS TO PARTICLE PHYSICS
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作者 杨文熊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第1期27-35,共9页
In this paper we consider that the momentum of a free particle motion withhigh-level speed presenting nonlinear effects may be expanded by using Laurent seriesand then obtain the complete expression of nonlinear and u... In this paper we consider that the momentum of a free particle motion withhigh-level speed presenting nonlinear effects may be expanded by using Laurent seriesand then obtain the complete expression of nonlinear and unsteady momentum. These nonlinear and unsieady phenoniena of high-level speed may further expand to the theory of kinematics and it may be determined by Fredholm's integral equation of the first kind. In addition, according to the nonlinear and unsteady momentum obtained the relations of the nonlinear mechanics equations .work and energy, mass and energymay be derived.Finaly .this paper also calculates those experimental results which done in particle physics for mu-mesons u±and fast neutrons n, these results are in agreement with data perfectly. 展开更多
关键词 theory of generalized nonlinear mechanics characteristic speed.Laurent senes particle physics.μ±meson fast neutron
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Transient response of multilayered hollow cylinder using various theories of generalized thermoelasticity
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作者 Daoud S. Mashat Ashraf M. Zenkour Khaled A. Elsibai 《Natural Science》 2010年第10期1171-1179,共9页
The present paper deals with thermoelastic problems of finitely long hollow cylinder com-posed of two different materials with axial sym- metry. The medium is traction-free, with neglig-ible body forces and with inter... The present paper deals with thermoelastic problems of finitely long hollow cylinder com-posed of two different materials with axial sym- metry. The medium is traction-free, with neglig-ible body forces and with internal and external heat generations. The governing equations for different theories of the generalized thermoe-lasticity are written in terms of displacement and temperature increment. The exact solution of the problem;using different theories of generalized thermoelasticity;has been deduced. The analytical expressions for displacements, temperature and stresses are found in final forms, and a numerical example has been taken to discuss the effect of the relaxation times. Finally, the results have been illustrated graphi- cally to find the responses of different theories. 展开更多
关键词 MULTILAYERED HOLLOW CYLINDER generalized Theories of THERMOELASTICITY RELAXATION TIMES
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Assignment of terahertz vibrational modes of L-glutamine using density functional theory within generalized-gradient approximation 被引量:5
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作者 张寒 张朝晖 +3 位作者 赵小燕 张天尧 燕芳 申江 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期211-218,共8页
The crystal structure of L-glutamine is stabilized by a three-dimensional network of intermolecular hydrogen bonds.We utilize plane-wave density functional theory lattice-dynamics calculations within the generalized-g... The crystal structure of L-glutamine is stabilized by a three-dimensional network of intermolecular hydrogen bonds.We utilize plane-wave density functional theory lattice-dynamics calculations within the generalized-gradient approximation(GGA), Perdew–Burke–Ernzerhof(PBE), PBE for solids(PBEsol), PBE with Wu–Cohen exchange(WC), and dispersion-corrected PBE, to investigate the effect of these intermolecular contacts on the absorption spectra of glutamine in the terahertz frequency range. Among these calculations, the solid-state simulated results obtained using the WC method exhibit a good agreement with the measured absorption spectra, and the absorption features are assigned with the help of WC. This indicates that the vibrational modes of glutamine were related to the combination of intramolecular and intermolecular motions, the intramolecular modes were dominated by rocking or torsion involving functional groups; the intermolecular modes mainly result from the translational motions of individual molecules, and the rocking of the hydrogenbonded functional groups. 展开更多
关键词 terahertz vibrational modes amino acid plane-wave density functional theory generalized-gradient approximation
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SOLUTION TO A PARAMETRIC EQUATION WITH GENERALIZED BOUNDARY CONDITION IN TRANSPORT THEORY
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作者 王胜华 姚爱翔 《Acta Mathematica Scientia》 SCIE CSCD 1992年第4期435-442,共8页
This paper deals with the solution of a parametric equation with generalized boundary condiiton in transport theory. It gives the distribution of parameter (so called delta-eigenvalue [1]) with which the equation has ... This paper deals with the solution of a parametric equation with generalized boundary condiiton in transport theory. It gives the distribution of parameter (so called delta-eigenvalue [1]) with which the equation has non-zero solution. A necessary and sufficient condition for the existence of; he control critical eigenvalue delta0 is established. 展开更多
关键词 SOLUTION TO A PARAMETRIC EQUATION WITH generalized BOUNDARY CONDITION IN TRANSPORT theory Za
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Numerical verification of similar Cam-clay model based on generalized potential theory 被引量:1
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作者 钟志辉 杨光华 +2 位作者 傅旭东 温勇 张玉成 《Journal of Central South University》 SCIE EI CAS 2014年第12期4707-4713,共7页
From the mathematical principles, the generalized potential theory can be employed to create constitutive model of geomaterial directly. The similar Cam-clay model, which is created based on the generalized potential ... From the mathematical principles, the generalized potential theory can be employed to create constitutive model of geomaterial directly. The similar Cam-clay model, which is created based on the generalized potential theory, has less assumptions,clearer mathematical basis, and better computational accuracy. Theoretically, it is more scientific than the traditional Cam-clay models. The particle flow code PFC3 D was used to make numerical tests to verify the rationality and practicality of the similar Cam-clay model. The verification process was as follows: 1) creating the soil sample for numerical test in PFC3 D, and then simulating the conventional triaxial compression test, isotropic compression test, and isotropic unloading test by PFC3D; 2)determining the parameters of the similar Cam-clay model from the results of above tests; 3) predicting the sample's behavior in triaxial tests under different stress paths by the similar Cam-clay model, and comparing the predicting results with predictions by the Cam-clay model and the modified Cam-clay model. The analysis results show that the similar Cam-clay model has relatively high prediction accuracy, as well as good practical value. 展开更多
关键词 剑桥模型 位势理论 数值验证 类似 广义 模型基 三轴压缩试验 数值试验
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The Quantum Chromodynamics Gas Density Drop and the General Theory of Relativity Ether
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作者 Rami Rom 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第2期445-454,共10页
β decay is one of the most fundamental and thoroughly studied nuclear decay. Surprisingly, the β decay rates were found to have a periodic time variability [1]. However, others argued that there is no evidence for s... β decay is one of the most fundamental and thoroughly studied nuclear decay. Surprisingly, the β decay rates were found to have a periodic time variability [1]. However, others argued that there is no evidence for such cyclic deviation from the exponential first order kinetics decay law [2]. Here we propose that the β decay is a pseudo-first order exchange reaction triggered by udd&utilde;exotic mesons and propose a QCD gas theory. In analogy to the atmospheric gas density, the proposed QCD gas density drops with elevation from the sun. Accordingly, we propose that the β decay rate periodic variability is due to the pseudo-first order exchange reaction kinetics and the QCD gas atmospheric density drop. The proposed QCD gas may be a possible candidate for Einstein’s general theory of relativity ether [3]. Our main results are the derived formulas for calculating the effective mass of the QCD gas and the cosmology perfect fluid equation of state dimensionless parameter, based on the measured ratio of the β decay rates at the earth trajectory aphelion and perihelion dates. . 展开更多
关键词 Nuclear Decay β Decay Rate Variability Atmospheric Density Quantum Chromodynamics (QCD) Exotic Mesons general theory of Relativity (GR) ETHER Dark Energy
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About the Conflicts between the Unitary Quantum Theory and the Special and General Relativity Theories
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作者 Leo G. Sapogin V. A. Dzhanibekov +3 位作者 M. A. Moкulsky Yu. A. Ryabov Yu. P. Savin V. I. Utchastkin 《Journal of Modern Physics》 2015年第6期780-785,共6页
The authors discuss contradictions between the principal branches of the modern physical picture of the universe. Space and time have been shown in the Unitary Quantum Theory (UQT) not to be connected one with the oth... The authors discuss contradictions between the principal branches of the modern physical picture of the universe. Space and time have been shown in the Unitary Quantum Theory (UQT) not to be connected one with the other, unlike in the Special Theory of Relativity. In UQT, time becomes Newtonian again, and the growth of the particle’s mass with growing speed proceeds from other considerations of physics. Unlike the quantum theory, the modern gravitation theory (the general theory of relativity) is not confirmed by experiments and needs to be considerably revised. 展开更多
关键词 UNITARY Quantum theory general RELATIVITY SPECIAL RELATIVITY Maxwell Equations LORENTZ TRANSFORMATIONS
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From Control Theory to Gravitational Waves
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作者 Jean-Francois Pommaret 《Advances in Pure Mathematics》 2024年第2期49-100,共52页
When D:ξ→η is a linear ordinary differential (OD) or partial differential (PD) operator, a “direct problem” is to find the generating compatibility conditions (CC) in the form of an operator D<sub>1:</su... When D:ξ→η is a linear ordinary differential (OD) or partial differential (PD) operator, a “direct problem” is to find the generating compatibility conditions (CC) in the form of an operator D<sub>1:</sub>η→ξ such that Dξ = η implies D<sub>1</sub>η = 0. When D is involutive, the procedure provides successive first-order involutive operators D<sub>1</sub>,...,D<sub>n </sub>when the ground manifold has dimension n. Conversely, when D<sub>1</sub> is given, a much more difficult “inverse problem” is to look for an operator D:ξ→η having the generating CC D<sub>1</sub>η = 0. If this is possible, that is when the differential module defined by D<sub>1</sub> is “torsion-free”, that is when there does not exist any observable quantity which is a sum of derivatives of η that could be a solution of an autonomous OD or PD equation for itself, one shall say that the operator D<sub>1</sub> is parametrized by D. The parametrization is said to be “minimum” if the differential module defined by D does not contain a free differential submodule. The systematic use of the adjoint of a differential operator provides a constructive test with five steps using double differential duality. We prove and illustrate through many explicit examples the fact that a control system is controllable if and only if it can be parametrized. Accordingly, the controllability of any OD or PD control system is a “built in” property not depending on the choice of the input and output variables among the system variables. In the OD case and when D<sub>1</sub> is formally surjective, controllability just amounts to the formal injectivity of ad(D<sub>1</sub>), even in the variable coefficients case, a result still not acknowledged by the control community. Among other applications, the parametrization of the Cauchy stress operator in arbitrary dimension n has attracted many famous scientists (G. B. Airy in 1863 for n = 2, J. C. Maxwell in 1870, E. Beltrami in 1892 for n = 3, and A. Einstein in 1915 for n = 4). We prove that all these works are already explicitly using the self-adjoint Einstein operator, which cannot be parametrized and the comparison needs no comment. As a byproduct, they are all based on a confusion between the so-called div operator D<sub>2</sub> induced from the Bianchi operator and the Cauchy operator, adjoint of the Killing operator D which is parametrizing the Riemann operator D<sub>1</sub> for an arbitrary n. This purely mathematical result deeply questions the origin and existence of gravitational waves, both with the mathematical foundations of general relativity. As a matter of fact, this new framework provides a totally open domain of applications for computer algebra as the quoted test can be studied by means of Pommaret bases and related recent packages. 展开更多
关键词 Differential Operator Differential Sequence Killing Operator Riemann Operator Bianchi Operator Cauchy Operator Control theory Controllability Elasticity general Relativity
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A new four-dimensional hyperchaotic Chen system and its generalized synchronization 被引量:7
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作者 贾立新 戴浩 惠萌 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期125-135,共11页
Based on the Chen chaotic system, a new four-dimensional hyperchaotic Chen system is constructed, and the basic dynamic behaviours of the system were studied, and the generalized synchronization has been observed in t... Based on the Chen chaotic system, a new four-dimensional hyperchaotic Chen system is constructed, and the basic dynamic behaviours of the system were studied, and the generalized synchronization has been observed in the coupled four-dimensional hyperchaotic Chen system with unknown parameters. The Routh Hurwitz theorem is used to derive the conditions of stability of this system. Furthermore based on Lyapunov stability theory, the control laws and adaptive laws of parameters are obtained to make generalized synchronization of the coupled new four-dimensional hyperchaotic Chen systems. Numerical simulation results are presented to illustrate the effectiveness of this method. 展开更多
关键词 hyperchaotic Chen system generalized synchronization Lyapunov stability theory
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Adaptive generalized matrix projective lag synchronization between two different complex networks with non-identical nodes and different dimensions 被引量:3
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作者 戴浩 贾立新 张彦斌 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期141-152,共12页
The adaptive generalized matrix projective lag synchronization between two different complex networks with non-identical nodes and different dimensions is investigated in this paper. Based on Lyapunov stability theory... The adaptive generalized matrix projective lag synchronization between two different complex networks with non-identical nodes and different dimensions is investigated in this paper. Based on Lyapunov stability theory and Barbalat's lemma, generalized matrix projective lag synchronization criteria are derived by using the adaptive control method. Furthermore, each network can be undirected or directed, connected or disconnected, and nodes in either network may have identical or different dynamics. The proposed strategy is applicable to almost all kinds of complex networks. In addition, numerical simulation results are presented to illustrate the effectiveness of this method, showing that the synchronization speed is sensitively influenced by the adaptive law strength, the network size, and the network topological structure. 展开更多
关键词 complex networks generalized matrix projective lag synchronization adaptive control Lyapunov stability theory
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Generalized Odd-Even Mode Theory and Mode Synthesis Antenna Design Approach
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作者 Wen-Jun Lu 《Electromagnetic Science》 2024年第1期20-37,共18页
In this article,studies on the multimode excitation problem of waveguides and antennas,the balance/unbalance mech-anism and the balanced feeding techniques in dipole antenna systems are first briefly historically revi... In this article,studies on the multimode excitation problem of waveguides and antennas,the balance/unbalance mech-anism and the balanced feeding techniques in dipole antenna systems are first briefly historically reviewed.In this context,general-ized odd-even mode theory is advanced to quantitatively and approximately describe the mutual coupling effect between a feed line and an antenna.As is mathematically deduced and demonstrated,the modal parity mismatch between the feed line and the antenna should ultimately dominate the unbalance phenomenon in antenna systems.Thus,an elegant,closed-form formula is derived to ap-proximately calculate the“unbalance degree”of a straight dipole off-center fed by a symmetric twin-wire line.Design approaches for the simplest,linear,1-D multimode resonant antennas are introduced.Moreover,the“falling tone excitation”law gauged based on prototype dipoles is revealed and used to develop a mode synthesis design approach for microstrip patch antennas(MPAs)and 2-D sectorial electric dipole antennas.Design examples with distinctive radiation performance are presented and discussed.Finally,possible development trends of multimode resonant antennas are prospected. 展开更多
关键词 generalized odd-even mode theory Modal parity mismatch Mode synthesis antenna design approach Multimode resonant antenna
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Generalized thermoelastic functionally graded spherically isotropic solid containing a spherical cavity under thermal shock 被引量:2
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作者 M.K.Ghosh M.Kanoria 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第10期1263-1278,共16页
This paper is concerned with the determination of thermoelastic displacement, stress and temperature in a functionally graded spherically isotropic infinite elastic medium having a spherical cavity, in the context of ... This paper is concerned with the determination of thermoelastic displacement, stress and temperature in a functionally graded spherically isotropic infinite elastic medium having a spherical cavity, in the context of the linear theory of generalized thermoelasticity with two relaxation time parameters (Green and Lindsay theory). The surface of cavity is stress-free and is subjected to a time-dependent thermal shock. The basic equations have been written in the form of a vector-matrix differential equation in the Laplace transform domain, which is then solved by an eigenvalue approach. Numerical inversion of the transforms is carried out using the Bellman method. Displacement, stress and temperature are computed and presented graphically. It is found that variation in the thermo-physical properties of a material strongly influences the response to loading. A comparative study with a corresponding homogeneous material is also made. 展开更多
关键词 generalized thermoelasticity functionally graded material (FGM) Green-Lindsay theory vector-matrix differential equation Bellman method
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Bifurcation analysis and exact traveling wave solutions for (2+1)-dimensional generalized modified dispersive water wave equation 被引量:3
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作者 宋明 王贝丹 曹军 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期148-153,共6页
We investigate (2+1)-dimensional generalized modified dispersive water wave (GMDWW) equation by utilizing the bifurcation theory of dynamical systems. We give the phase portraits and bifurcation analysis of the plane ... We investigate (2+1)-dimensional generalized modified dispersive water wave (GMDWW) equation by utilizing the bifurcation theory of dynamical systems. We give the phase portraits and bifurcation analysis of the plane system corresponding to the GMDWW equation. By using the special orbits in the phase portraits, we analyze the existence of the traveling wave solutions. When some parameter takes special values, we obtain abundant exact kink wave solutions, singular wave solutions, periodic wave solutions, periodic singular wave solutions, and solitary wave solutions for the GMDWW equation. 展开更多
关键词 bifurcation theory generalized modified dispersive water wave equation traveling wave solution
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Free vibration and critical speed of moderately thick rotating laminated composite conical shell using generalized differential quadrature method 被引量:1
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作者 K.DANESHJOU M.TALEBITOOTI R.TALEBITOOTI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第4期437-456,共20页
The generalized differential quadrature method (GDQM) is employed to con- sider the free vibration and critical speed of moderately thick rotating laminated compos- ite conical shells with different boundary conditi... The generalized differential quadrature method (GDQM) is employed to con- sider the free vibration and critical speed of moderately thick rotating laminated compos- ite conical shells with different boundary conditions developed from the first-order shear deformation theory (FSDT). The equations of motion are obtained applying Hamilton's concept, which contain the influence of the centrifugal force, the Coriolis acceleration, and the preliminary hoop stress. In addition, the axial load is applied to the conical shell as a ratio of the global critical buckling load. The governing partial differential equations are given in the expressions of five components of displacement related to the points ly- ing on the reference surface of the shell. Afterward, the governing differential equations are converted into a group of algebraic equations by using the GDQM. The outcomes are achieved considering the effects of stacking sequences, thickness of the shell, rotating velocities, half-vertex cone angle, and boundary conditions. Furthermore, the outcomes indicate that the rate of the convergence of frequencies is swift, and the numerical tech- nique is superior stable. Three comparisons between the selected outcomes and those of other research are accomplished, and excellent agreement is achieved. 展开更多
关键词 generalized differential quadrature method (GDQM) natural frequency rotating conical shell first-order shear deformation theory (FSDT) critical speed
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HOMOCLINIC ORBITS IN PERTURBED GENERALIZED HAMILTONIAN SYSTEMS 被引量:1
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作者 赵晓华 李继彬 黄克累 《Acta Mathematica Scientia》 SCIE CSCD 1996年第4期361-374,共14页
It this paper we obtain existence and bifurcation theorems for homoclinic orbits in three-dimeensional,time dependent and independent,perturbations of generalized Hamiltonian differential equations defined on three-d... It this paper we obtain existence and bifurcation theorems for homoclinic orbits in three-dimeensional,time dependent and independent,perturbations of generalized Hamiltonian differential equations defined on three-dimensional Poisson manifolds.Thed we apply them to a truncated spectral model of the quasi-geostrophic flow on a cyclic β-plane. 展开更多
关键词 bifurcation Poisson bracket generalized Hamiltonian system homoclinic orbit Melnikov method perturbation theory
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Generalization Rough Set Theory 被引量:2
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作者 肖迪 张军峰 胡寿松 《Journal of Donghua University(English Edition)》 EI CAS 2008年第6期654-658,共5页
In order to avoid the discretization in the classical rough set theory, a generlization rough set theory is proposed. At first, the degree of general importance of an attribute and attribute subsets are presented. The... In order to avoid the discretization in the classical rough set theory, a generlization rough set theory is proposed. At first, the degree of general importance of an attribute and attribute subsets are presented. Then, depending on the degree of general importance of attribute, the space distance can be measured with weighted method. At last, a generalization rough set theory based on the general near neighborhood relation is proposed. The proposed theory partitions the universe into the tolerant modules, and forms lower approximation and upper approximation of the set under general near neighborhood relationship, which avoids the discretization in Pawlak's rough set theory. 展开更多
关键词 粗糙集理论 社区关系 属性集 空间距离 宇宙理论 加权法 上近似 下近似
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