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1.
Dai Tian-min 《应用数学和力学(英文版)》2003,24(10):1119-1125
Based on the restudies of existing polar continuum theories rather complete systems of basic balance laws and equations for
micropolar continuum theory are presented. In these new systems not only the additional angular momentum, surface moment and
body moment produced by the linear momentum, surface force and body force, respectively, but also the additional velocity
produced by the angular velocity are considered. The new coupled balance laws of linear momentum, angular momentum and energy
are reestablished. From them the new coupled local and nonlocal balance equations are naturally derived. Via contrast it can
be clearly seen that the new results are believed to be rather general and complete.
Foundation items: the National Natural Science Foundation of China (10072024); the Research Foundation of Liaoning Education Committee (990111001)
Biography: Dupai Tian-min (1931≈) 相似文献
2.
The asymptotic theory of initial value problems for semilinear ware equations in two space dimensions was dealt with. The
well-posedness and vaildity of formal approximations on a long time scale were discussed in the twice continuous classical
space. These results describe the behavior of long time existence for the validity of formal approximations. And an application
of the asymptotic theory is given to analyze a special wave equation in two space dimensions.
Foundation item: Sichuan Youth Foundation (1999-09)
Biography: LAI Shao-yong (1965−), Associate Professor 相似文献
3.
A numerical method for two-phase flow with hydrodynamics behavior was considered. The nonconservative hyperbolic governing equations proposed by Saurel and Gallout were adopted. Dissipative effects were neglected but they could be included in the model without major difficulties. Based on the opinion proposed by Abgrall that “a two phase system, uniform in velocity and pressure at t = 0 will be uniform on the same variable during its temporal evolution“, a simple accurate and fully Eulerian numerical method was presented for the simulation of multiphase compressible flows in hydrodynamic regime. The numerical method relies on Godunov-typescheme, with HLLC and Lax-Friedrichs type approximate Riemann solvers for the resolution of conservation equations, and nonconservative equation. Speed relaxation and pressure relaxation processes were introduced to account for the interaction between the phases. Test problem was presented in one space dimension which illustrated that our scheme is accurate, stable and oscillation free. 相似文献
4.
黄再兴 《应用数学和力学(英文版)》1999,20(7):764-772
In this paper, nonlinear constitutive equations are deduced strictly according to the constitutive axioms of rational continuum
mechanics. The existing judgments are modified and improved. The results show that the constitutive responses of nonlocal
thermoelastic body are related to the curvature and higher order gradient of its material space, and there exists an antisymmetric
stress whose average value in the domain occupied by thermoelastic body is equal to zero. The expressions of the antisymmetric
stress and the nonlocal residuals are given. The conclusion that the directions of thermal conduction and temperature gradient
are consistent is reached. In addition, the objectivity about the nonlocal residuals and the energy conservation law of nonlocal
field is discussed briefly, and a formula for calculating the nonlocal residuals of energy changing with rigid motion of the
spatial frame of reference is derived.
Foundation item: the Natural Science Foundation of Province Jiangshu (BK97063) 相似文献
5.
The criterion for the points in the parameter space being on the stability boundary of linear Hamiltonian system depending
on arbitrary numbers of parameters was given, through the sensitivity analysis of eigenvalues and eigenvectors. The results
show that multiple eigenvalues with Jordan chain take a very important role in the stability of Hamiltonian systems.
Foundation item: the National Natural Science Foundation of China (10072012); the National Natural Science Foundation of Russia
Biography: QI Zhao-hui (1964-) 相似文献
6.
On the isometric isomorphism of probabilistic metric spaces 总被引:1,自引:0,他引:1
刘明学 《应用数学和力学(英文版)》2002,23(5):614-617
IntroductionTherearetwokindsofisometricisomorphisminprobabilisticmetricspacetheory (see[1 -9] ) .ThefirstisthataPMspace (E ,F)isisometricallyisomorphictoanotherPMspace(E′,F′) ,andthesecondisthataPMspaces(E ,F)isisometricallyisomorphictoageneratingspaceofquasi_met… 相似文献
7.
By applying the technique of continuous partition of unity and Tychonoff’s fixed point theorem, some new collectively fixed point theorems for a family of set-valued mappings defined on the product space of noncompact G-convex spaces are proved. As applications, some nonempty intersetion theorems of Ky Fan type for a family of subsets of the product space of G-convex spaces are proved; An existence theorem of solutions for a system of nonlinear inequalities is given in G-convex spaces and some equilibrium existence theorems of abstract economies are also obtained in G-convex spaces. Our theorems improve, unify and generalized many important known results in recent literature. 相似文献
8.
The mixed finite element(MFE) methods for a shallow water equation systemconsisting of water dynamics equations, silt transport equation, and the equation of bottomtopography change were derived. A fully discrete MFE scheme for the discrete-time alongcharacteristics is presented and error estimates are established. The existence andconvergence of MFE solution of the discrete current velocity, elevation of the bottomtopography, thickness of fluid column, and mass rate of sediment is demonstrated. 相似文献
9.
Ma Jun-hai Associate Professor Doctor Chen Yu-shu Professor Doctor Director 《应用数学和力学(英文版)》2000,21(11):1237-1245
The state space reconstruction is the major important quantitative index for describing non-linear chaotic time series. Based on the work of many scholars, such as: N.H.Packard, F.Takens, M. Casdagli, J.F.Gibson, CHEN Yu-shu et al, the state space was reconstructed using the method of Legendre coordinate. Several different scaling regimes for lag time τ were identified. The influence for state space reconstruction of lag time τ was discussed. The result tells us that is a good practical method for state space reconstruction. 相似文献
10.
By combining Chapman-Enskog expansion with the BGK approximation to Baltzmann equation and Navier-Stokes equation was obtained.
And an expression of Darcy’s law was obtained through taking variable average over Navier-Stokes equation on some representative
space in porous media, and finally an example was taken to prove its reliability.
Foundation items: the National Natural Science Foundation of China (10372094); the Natural Science Foundation of Zhejiang Province, China
(M103082, M102053); the Science Foundation of Education Department of Zhejiang Province, China (20030871)
Biography: Xu You-sheng (1963∼), Associate Professor, Doctor 相似文献
11.
RESTUDY OF COUPLED FIELD THEORIES FOR MICROPOLAR CONTINUA (Ⅱ)-THERMOPIEZOELECTRICITY AND MAGNETOTHERMOELASTICITY 总被引:1,自引:1,他引:1
The theories of thermopiezoelectricity and magnetoelasticity for micropolar continua have been systematically developed by
W. Nowacki. In this paper, the theories are restudied. The reason why they were restricted to linear cases is analyzed. The
more general conservation principle of energy, energy balance equation and Hamilton principle of thermopiezoelectricity and
magnetoelasticity for micropolar continua are established. The corresponding complete equations of motion and boundary conditions
as well as balance equations of energy rate for local and nonlocal micropolar thermopiezoelectricity and magnetothermoelasticity
are naturally derived. By means of two new functionals and total variation the boundary conditions of displacement, microrotation,
electric potential and temperature are also given.
Foundation item: the National Natural Science Foundation of China (10072024); the International Cooperation Project of the NSFC (10011130235)
and the DFG (51520001); the Research Foundation of the Liaoning Education Committee (990111001)
Biography: DAI Tian-min (1931-) 相似文献
12.
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. 相似文献
13.
ZHANGShao-qin YANGWei-yang 《应用数学和力学(英文版)》2004,25(6):714-722
A newly developed Z fracture criterion for the composite materials was introduced, the new concepts of in-plane average strain, in-plane dilatational strain energy density factor and reciprocal characteristic function were presented. Many experimental results show that the Z fracture criterion can be well used to predict the crack propagating direction for mode f crack in carbon-fiber reinforced composite laminates. 相似文献
14.
Applying the theory of stratification, the solution space structure about a class of deformed Navier-Stokes equation isdetermined.
It is proved that such kind of equation has no Ck (k≥2) stable solution by the fact that the strate transversale is a null set.
Foundation item: the National Natural Science Foundation of China (19971054), Shanghai Natural Science Foundation (99ZA14034)
Biography: HE You-hua (1960-) 相似文献
15.
Ding Xie-ping 《应用数学和力学(英文版)》2003,24(6):659-672
A new family of set-valued mappings from a topological space into generalized convex spaces was introduced and studied. By
using the continuous partition of unity theorem and Brouwer fixed point theorem, several existence theorems of maximal elements
for the family of set-valued mappings were proved under noncompact setting of product generalized convex spaces. These theorems
improve, unify and generalize many important results in recent literature.
Contributed by DING Xie-ping
Foundation items: the National Natural Science Foundation of China (19871059); the Natural Science Foundation of Education Department of Sichuan
Province of China ([2000]25)
Biography: DING Xie-ping (1938∼) 相似文献
16.
Ding Xie-ping 《应用数学和力学(英文版)》2003,24(9):1017-1024
By applying existence theorems of maximal elements for a family of GB-majorized mappings in a product space of G-convex spaces, some coincidence theorem, Fan-Browder type fixed point theorem
and some existence theorems of solutions for a system of minimax inequalities are proved under noncompact setting of G-convex
spaces. These theorems improve and generalize many important known results in literature.
Contributed by Duping Xie-ping
Foundation items: the National Natural Science Foundation of China (19871059); the Natural Science Foundation of Education Department of Sichuan
Province ([2000]25)
Biography: Duping Xie-ping (1938∼), Professor (E-mail: dingxip@sichu.edu.cn) 相似文献
17.
IntroductionGenerallyspeaking ,acrackinviscoelasticmaterialswillgrowinsomeunknownspeedeveniftheappliedloadisquasistatic,thusthemaindifficultyisinducedindervingtheenergyreleaserate .Knowledgeoftheconditiongoverningthedelaminationincompositelaminateswithviscoelasticlayersisofparamountimportanceinpracticalapplications.Forexample,inplasticencapsulatedICpackages,theinterfacialdelaminationbetweentheSilicondieandviscoelasticepoxymoldingcompoundunderthethermalloadingisthemainfailuremodeofthestructure… 相似文献
18.
Dai Tian-min 《应用数学和力学(英文版)》2003,24(10):1126-1133
The purpose is to reestablish the balance laws of momentum, angular momentum and energy and to derive the corresponding local
and nonlocal balance equations for micromorphic continuum mechanics and couple stress theory. The desired results for micromorphic
continuum mechanics and couple stress theory are naturally obtained via direct transitions and reductions from the coupled
conservation law of energy for micropolar continuum theory, respectively. The basic balance laws and equations for micromorphic
continuum mechanics and couple stress theory are constituted by combining these results derived here and the traditional conservation
laws and equations of mass and microinertia and the entropy inequality. The incomplete degrees of the former related continuum
theories are clarified. Finally, some special cases are conveniently derived.
Foundation items: the National Natural Science Foundation of China (10072024); the Research Foundation of Liaoning Education Committee (990111001)
Biography: DAI Tian-min (1931≈) 相似文献
19.
IntroductionMuchworkhasbeendevotedinthelastfewdecadestothemeasurementandmodelingofthescalinglawofstructurefunctionofturbulentflows.Theso_called“velocitystructurefunctionofordern”forturbulentflowsisdefinedas〈ΔV(r) n〉 ,whereΔV(r) =V(x r) -V(x)isthevelocitycomp… 相似文献
20.
For the so-called quadratic family, it is proved that, there exists a positive Lebesgue measure set E in the parameter space such that the corresponding map has a dense critical orbit in the support set of the invariant measure for almost all parameters in E; it is also proved that there is a dense set in E such that the critical orbit of the corresponding map enter the reversed fixed point. 相似文献