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不(非)均匀世界永恒运动与发展的动力
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作者 郑文兵 《商丘师范学院学报》 CAS 2013年第10期35-42,共8页
自然界、人类社会与思维(意识)等领域中,都普遍地存在着核心与非核心的结构差异。世界上的任何事物与结构,例如物质、质量、能量、空间、时间、力场、电场、磁场、矛盾、概率、人类社会、人类思维等现象,都普遍地存在着不(非)均匀、不... 自然界、人类社会与思维(意识)等领域中,都普遍地存在着核心与非核心的结构差异。世界上的任何事物与结构,例如物质、质量、能量、空间、时间、力场、电场、磁场、矛盾、概率、人类社会、人类思维等现象,都普遍地存在着不(非)均匀、不平均分布的共同特征。这种不(非)均匀的特性不仅表现在现实世界中,而且还表现在频率与概率分布中。根据热力学第二定律与系统自组织等理论,结合"矛盾"概念,我们可以判断出世界的不(非)均匀特征其实正是唯物辩证法两个总特征——普遍联系与永恒发展的内在动力。 展开更多
关键词 不(非)均匀 核心 核心 频率与概率 内在动力
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Spatiotemporal Similaritons in (3+l)-Dimensional Inhomogeneous Nonlinear Medium with Cubic-Quintic Nonlinearity 被引量:3
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作者 陈翼翔 陆璇辉 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第5期871-877,共7页
We obtain exact spatiotemporal similaritons to a (3+ l)-dimensional inhomogeneous nonlinear Schrodinger equation, which describes the propagation of optical pulses in a cubic-quintic nonlinearity medium with distri... We obtain exact spatiotemporal similaritons to a (3+ l)-dimensional inhomogeneous nonlinear Schrodinger equation, which describes the propagation of optical pulses in a cubic-quintic nonlinearity medium with distributed dispersion and gain. A one-to-one correspondence between such self-similar waves and solutions of the elliptic equation is found when a certain compatibility condition is satisfied. Based on exact solutions, we discuss evolutional behaviors of self-similar cnoidal waves and chirped similaritons in two kind of typicai soliton control systems. Moreover, the comparison between chirped similaritons and chirp-free solitons is given. 展开更多
关键词 spatiotemporal similaritons (3+l)-dimensional cubic-quintic nonlinear SchrSdinger equation dynamical behaviors
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Effect of non-uniform stress characteristics on stress measurement in specimen 被引量:6
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作者 廖凯 吴运新 +2 位作者 龚海 闫鹏飞 郭俊康 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第5期789-794,共6页
There is a remarkable difference in stress distribution between a specimen and a plate removed from the specimen.The plate presents a uniform stress distribution whereas the specimen presents a non-uniform stress dist... There is a remarkable difference in stress distribution between a specimen and a plate removed from the specimen.The plate presents a uniform stress distribution whereas the specimen presents a non-uniform stress distribution.Firstly,the real stress distributions in plates with thickness of 30,40 and 50 mm and then in the specimens were obtained through simulation and X-ray surface stress measurement.Secondly,in order to study the impact of specimens shapes and processing ways on the results accuracy,two irregular shapes (parallelogram and trapezoid) and two processing ways (saw and electron discharge machining (EDM)) were compared and analyzed by simulation and experiment using layer removal method,then the specimen effects on measurement results were evaluated.The results show that:1) the non-uniform stress distribution characteristics of the specimen near the surface of the cut is significant,the range of non-uniform stress distribution is approximately one-thickness distance away from the cut,and it decreases gradually along the depth;2) In order to ensure the stability in the results,it is suitable to take the specimen plane size 2-3 times of its thickness;3) Conventional processing methods have little effect on experimental results and the average deviation is less than 5%. 展开更多
关键词 SPECIMEN non-uniform characteristic layer removal method (LRM) stress distribution aluminum alloy plate
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Impact of permafrost degradation on embankment deformation of Qinghai-Tibet Highway in permafrost regions 被引量:7
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作者 彭惠 马巍 +1 位作者 穆彦虎 金龙 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期1079-1086,共8页
Based on long-term monitoring data, the relationships between permafrost degradation and embankment deformation are analyzed along the Qinghai-Tibet Highway(QTH). Due to heat absorbing effect of asphalt pavement and c... Based on long-term monitoring data, the relationships between permafrost degradation and embankment deformation are analyzed along the Qinghai-Tibet Highway(QTH). Due to heat absorbing effect of asphalt pavement and climate warming,permafrost beneath asphalt pavement experienced significant warming and degradation. During the monitoring period, warming amplitude of the soil at depth of 5 m under asphalt ranged from 0.21 °C at the XD1 site to 0.5 °C at the KL1 site. And at depth of 10 m, the increase amplitude of ground temperature ranged from 0.47 °C at the NA1 site to 0.07 °C at the XD1 site. Along with ground temperature increase, permafrost table beneath asphalt pavement decline considerably. Amplitude of permafrost table decline varied from 0.53 m at the KL1 site to 3.51 m at the NA1 site, with mean amplitude of 1.65 m for 8 monitoring sites during the monitoring period. Due to permafrost warming and degradation, the embankment deformation all performed as settlement at these sites. At present, those settlements still develop quickly and are expected to continue to increase in the future. The embankment deformations can be divided into homogeneous deformation and inhomogeneous deformation. Embankment longitudinal inhomogeneous deformation causes the wave deformations and has adverse effects on driving comfort and safety, while lateral inhomogeneous deformation causes longitudinal cracks and has an adverse effect on stability. Corresponding with permafrost degradation processes,embankment settlement can be divided into four stages. For QTH, embankment settlement is mainly comprised of thawing consolidation of ice-rich permafrost and creep of warming permafrost beneath permafrost table. 展开更多
关键词 Qinghai-Tibet Highway(QTH) permafrost degradation embankment deformation thawing settlement
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Dissipation of Nonlinear Wave in Inhomogeneous Dust Plasma Crystal
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作者 FENG Tian-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期941-944,共4页
A Korteweg-de Vires-type (KdV-type) equation and a modified Nonlinear Schrodinger equation (NLSE) for the dust lattice wave (DLW) are derived in a weakly inhomogeneous dust plasma crystal. It seems that the ampl... A Korteweg-de Vires-type (KdV-type) equation and a modified Nonlinear Schrodinger equation (NLSE) for the dust lattice wave (DLW) are derived in a weakly inhomogeneous dust plasma crystal. It seems that the amplitude and the velocity of the dust lattice solitary waves decay exponentiaJly with increasing time in a dust lattice. The modulational instability of this dust lattice envelope waves is investigated as well. It is found that the waves are modulational stable under certain conditions. On the other hand, the waves are modulationaJ unstable if the conditions are not satisfied. 展开更多
关键词 reductive perturbation method dust lattice wave
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Calculation of the Cylindrical and Spherical Underground Constructions in the Nonlinear Inhomogeneous Rock Massive under the Different Emergency Influences
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《Journal of Physical Science and Application》 2013年第3期156-162,共7页
Reliable and economical design of constructions and facilities are primarily caused by the determination of the stress-strain condition and strength assessing of structural elements, and the entire structure as a whol... Reliable and economical design of constructions and facilities are primarily caused by the determination of the stress-strain condition and strength assessing of structural elements, and the entire structure as a whole under various pressing conditions and taking into account the real properties of materials. The resulting equations allow conducting a qualitative analysis of the dependency of the structures' stress-strain condition from the material heterogeneity and, particularly, answering the question ~hnut th~ inflHenee nfthe ~nnrnYimntinn rnethnd of heterogeneity functions on the results of calculation. 展开更多
关键词 Stress-strain condition qualitative analysis HETEROGENEITY material properties.
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Nonlinear Waves in an Inhomogeneous Fluid Filled Elastic Tube
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作者 DUANWen-Shan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期115-118,共4页
In a thin-walled, homogeneous, straight, long, circular, and incompressible fluid filled elastic tube, small but finite long wavelength nonlinear waves can be describe by a KdV (Korteweg de Vries) equation, while the ... In a thin-walled, homogeneous, straight, long, circular, and incompressible fluid filled elastic tube, small but finite long wavelength nonlinear waves can be describe by a KdV (Korteweg de Vries) equation, while the carrier wave modulations are described by a nonlinear Schr?dinger equation (NLSE). However if the elastic tube is slowly inhomogeneous, then it is found, in this paper, that the carrier wave modulations are described by an NLSE-like equation. There are soliton-like solutions for them, but the stability and instability regions for this soliton-like waves will change, depending on what kind of inhomogeneity the tube has. 展开更多
关键词 nonlinear wave INHOMOGENEITY
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Thermo-Magneto-Electric Currents with Dynamical Magnetization Inhomogeneities
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作者 Santosh Kumar Kudtarkar 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第9期504-512,共9页
We study the effect of potential and thermal gradient induced non-equilibrium magnetization in quasi1-d itinerant magnets.A semi-phenomenological theory is employed in conjunction with the drift-diffusion model forthi... We study the effect of potential and thermal gradient induced non-equilibrium magnetization in quasi1-d itinerant magnets.A semi-phenomenological theory is employed in conjunction with the drift-diffusion model forthis study.Using the methods of non-equilibrium thermodynamics,we derive the transport currents correspondingto charge,heat,and magnetization flows in the presence of non-equilibrium magnetization textures.It is shown howtime-dependent magnetic textures give rise to charge and thermal currents even in the absence of external potential andthermal gradients through spin pumping.The presence of dynamical textures also affect the thermodynamic parametersof the system.As an application,we consider the case of a helimagnet. 展开更多
关键词 current and temperature driven spin pumping THERMOELECTRIC thermomagnetic
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Hardy-Type Inequalities on H-Type Groups andAnisotropic Heisenberg Groups 被引量:7
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作者 Yongyang JIN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2008年第5期567-574,共8页
The author obtains some weighted Hardy-type inequalities on H-type groups and anisotropic Heisenberg groups. These inequalities generalize some recent results due to N. Garofalo, E. Lanconelli, I. Kombe and P. Niu et al.
关键词 Hardy-type inequalities H-type groups Anisotropic Heisenberg groups
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Lattice Boltzmann Simulation of Mixed Convection Heat Transfer in a Driven Cavity with Non-uniform Heating of the Bottom Wall
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作者 Soufiene Bettaibi Ezeddine Sediki +1 位作者 Frdric Kuznik Sauro Succi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第1期91-100,共10页
The goal of this article is to study numerically the mixed convection in a differentially heated rid-driven cavity with non-uniform heating of the bottom wall. The velocity field is solved by a hybrid scheme with mult... The goal of this article is to study numerically the mixed convection in a differentially heated rid-driven cavity with non-uniform heating of the bottom wall. The velocity field is solved by a hybrid scheme with multiple relaxation time Lattice Boltzmann (MRT-LBM) model, while the temperature field is obtained by resolution of the energy balance equation using the finite difference method (FDM). First, the model is checked and validated using data from the riterature. Validation of the present resuJts with those available in the literature shows a good agreement. A good efficiency in time simulation is confirmed. Thereafter, the model has been applied to mixed convection in a driven cavity with non-uniform heating wall at the fixed Grashof number Gr = 106. It is found that, the heat transfer is weakened as the Richardson number is augmented. For Gr = 106, we note the appearance of secondary vortices at different positions of the cavity corners. 展开更多
关键词 lattice Boltzmann method (LBM) finite difference method (FDM) heated Lid-driven cavity mixed convection non-uniform heating wall
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Nonlocal Free Energy of a Spatially Inhomogeneous Superconductor
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作者 K.V.Grigorishin B.I.Lev 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第5期879-892,共14页
The microscopic approach is developed for obtaining of the free energy of a superconductor based on direct calculation of the vacuum amplitude.The free energy functional of the spatially inhomogeneous superconductor i... The microscopic approach is developed for obtaining of the free energy of a superconductor based on direct calculation of the vacuum amplitude.The free energy functional of the spatially inhomogeneous superconductor in a magnetic field is obtained with help of the developed approach.The obtained functional is generalization of GinzburgLandau functionals for any temperature,for arbitrary spatial variations of the order parameter and for the nonlocality of a magnetic response and the order parameter.Moreover,the nonlocality of the magnetic response is the consequence of order parameter's nonlocality.The extremals of this functional are considered in the explicit form in the low-and high-temperature limit at the condition of slowness of spatial variations of the order parameter. 展开更多
关键词 uncoupling of correlations vacuum amplitude order parameter magnetic response NONLOCALITY
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A SECOND ORDER DIFFERENCE SCHEME WITH NONUNIFORM MESHES FOR NONLINEAR PARABOLIC SYSTEM
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作者 WANZhengsu CHENGuangnan 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2003年第2期199-208,共10页
In this paper, a difference scheme with nonuniform meshes is established for the initial-boundary problem of the nonlinear parabolic system. It is proved that the difference scheme is second order convergent in spaces... In this paper, a difference scheme with nonuniform meshes is established for the initial-boundary problem of the nonlinear parabolic system. It is proved that the difference scheme is second order convergent in spacestep and timestep. 展开更多
关键词 second order DIFFERENCE nonuniform meshes
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A numerical study of shock-interface interaction and prediction of the mixing zone growth in inhomogeneous medium
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作者 Yang Wang Gang Dong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第12期33-44,共12页
The growth of mixing zone on an interface induced by Richtmyer-Meshkov(RM)instability occurs frequently in natural phenomena and in engineering applications.Usually,the medium on which the RM instability happens is in... The growth of mixing zone on an interface induced by Richtmyer-Meshkov(RM)instability occurs frequently in natural phenomena and in engineering applications.Usually,the medium on which the RM instability happens is inhomogeneous,the effect of medium inhomogeneity on the growth of the mixing zone during the RM instability is still not clear.Therefore,it is necessary to investigate the RM instability in inhomogeneous medium.Based on a high-order computational scheme,the interactions of a density interface with an incident shock wave(ISW)in inhomogeneous medium are numerically simulated by solving the compressible Navier-Stokes equations.The effect of the inhomogeneity on the interface evolution after the passage of ISW through the interface is investigated.The results show that the interface morphology develops in a distinctive "spike-spike"structure in inhomogeneous medium.Particularly,the spike structure on the bottom of the interface is due to the reverse induction of RM instability by curved ISW or reflected shock wave.With the increase of inhomogeneity,the growth rate of the mixing zone width on interface increases,and the wave patterns caused by interaction between the shock wave and interface are more complex.Compared with RM instability in homogeneous medium,the inhomogeneous distribution of the density in medium further enhances the baroclinic effect and induces larger vorticity in flow field.Therefore,the interface is stretched much more significantly under the induction of enhanced vorticity in inhomogeneous medium.Based on above analyses,a model for predicting the growth of mixing zone width on the interface after the passage of ISW is proposed,in order to provide a useful method for evaluations of perturbation growth behavior during the RM instability in inhomogeneous medium. 展开更多
关键词 RM instability Mixing zone growth Inhomogeneous medium Numerical simulation Predictive model
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Static Axially Symmetric Models and Structure Scalars in Self-Interacting Brans–Dicke Gravity
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作者 M. Sharif Rubab Manzoor 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第7期39-48,共10页
This paper investigates static axially symmetric models in self-interacting Brans-Dicke gravity. We discuss physically feasible sources of models, derive field equations as well as evolution equations from Bianchi ide... This paper investigates static axially symmetric models in self-interacting Brans-Dicke gravity. We discuss physically feasible sources of models, derive field equations as well as evolution equations from Bianchi identities and construct structure scalars. Using these scalars and evolution equations, the inhomogeneity factors of the system are evaluated. It is found that structure scalars related to double dual of Riemann tensor control the density inhomogeneity. Finally, we obtain exact solutions of homogenous isotropic and inhomogeneous anisotropic spheroid models. It turns out that homogenous solutions reduce to Schwarzschild type interior solutions for a spherical case. We conclude that homogenous models involve homogenous distribution of scalar field whereas inhomogeneous correspond to inhomogeneous sca/ar field. 展开更多
关键词 self-interacting Brans Dicke Theory self-gravitating systems structure scalars Non-sphericalsources interior solutions
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