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1.
In account of the famous Cebysev inequality, a rich theory has appeared in the literature. We establish some new weighted Cebysev type integral inequalities. Our proofs are of independent interest and provide new estimates on these types of inequalities.  相似文献   
2.
IntroductionInordertogetridoftherestrictiontodiscreteBabuska_Brezzi’sconditionsinresearchesofmixedfiniteelement (MFE)methods,oneusuallyusesthestabilizedMFEmethodsformat[1] .Thereareanumberofstabilizedmethods (see ,e.g .,Refs.[1- 7]andthereferencestherein) ,whichh…  相似文献   
3.
Some experiments were made for the buoyant jet from a square orifice with a square disc placed on it in static ambient and concentration along the axis in self-similar area behind disc was measured. And at the same time a three-dimensional mathematical model was established to simulate the whole flowing under different conditions. All the results predicted by the numerical calculation were substantiated by the experiments. The results were compared with experiential formula for obstructed round buoyant vertical jets in static ambient and it was found that the two concentration distributions had good accordance. Star shape of temperature isolines on cross-sections in the near areas from the disc was found and it was a very special figure for obstructed square buoyant vertical jets with a square disc. The shape will transform to concentric circles gradually alike to the round buoyant vertical jet in self-similar area with increasing of the distance from the disc.  相似文献   
4.
IntroductionDuetotheintrinsiccouplingcharacteristicsbetweenelectricandelasticbehaviors,thatis,appliedmechanicalloadingproduceselasticdeformation ,aswellaselectricfield ,andconverselyelectricfieldcangiverisetoelasticdeformation ,piezoelectricmaterialshave…  相似文献   
5.
An efficient numerical approach for the general thermomechanical problems was developed and it was tested for a two-dimensional thermoelasticity problem. The main idea of our numerical method is based on the reduction procedure of the original system of PDEs describing coupled thermomechanical behavior to a system of Differential Algebraic Equations (DAEs) where the stress-strain relationships are treated as algebraic equations. The resulting system of DAEs was then solved with a Backward Differentiation Formula (BDF) using a fully implicit algorithm. The described procedure was explained in detail, and its effectiveness was demonstrated on the solution of a transient uncoupled thermoelastic problem, for which an analytical solution is known, as well as on a fully coupled problem in the two-dimensional case.  相似文献   
6.
A new direct method for solving unsymmetrical sparse linear systems(USLS) arising from meshless methods was introduced. Computation of certain meshless methods such as meshless local Petrov-Galerkin (MLPG) method need to solve large USLS. The proposed solution method for unsymmetrical case performs factorization processes symmetrically on the upper and lower triangular portion of matrix, which differs from previous work based on general unsymmetrical process, and attains higher performance. It is shown that the solution algorithm for USLS can be simply derived from the existing approaches for the symmetrical case. The new matrix factorization algorithm in our method can be implemented easily by modifying a standard JKI symmetrical matrix factorization code. Multi-blocked out-of-core strategies were also developed to expand the solution scale. The approach convincingly increases the speed of the solution process, which is demonstrated with the numerical tests.  相似文献   
7.
IntroductionThestabilityoftheintervalmatrixanduncertainsystemwithtimedelayhavebeenconsideredbyresearchersinthepapers [1 -1 3 ] .Thestabilityandαexponentialstabilityofthefollowingintervaldynamicalsystemwithsingletimedelay x(t) =N[P ,Q]x(t) +N[C ,D]x(t-τ)havebeenconsi…  相似文献   
8.
STABILITY ANALYSIS OF HOPFIELD NEURAL NETWORKS WITH TIME DELAY   总被引:3,自引:0,他引:3  
IntroductionInrecentyearsthedynamicbehaviorofthefollowingHopfieldneuralnetworksmodelwithtimedelayhavebeeninvestigatedthoroughlyCi xi(t) =-xiRi + ∑nj=1Tijfj(xj(t-τij) ) +Ii   (i=1 ,2 ,… ,n) ,( 1 )whereRi,CiandIirepresentresistance ,capacitanceandelectriccurrent.Ri,Ciarepa…  相似文献   
9.
IntroductionThereareoftensomestructuresorcomponentswhichcanonlytransferonespecialformofstress,suchasthecablewhichcanonlybeusedtotransferthetensionstressandthecontactcomponentwhichcanonlytransferthepressure.Ingeneral,suchproblemsareoftencalledtheunilat…  相似文献   
10.
IntroductionConsiderageneralizedLienardsystemsoftheform x=h(y) -F(x) , y=-g(x) ,( 1 )wherethefunctionsF ,gandhareLipschitzcontinuousandsatisfyF( 0 ) =h( 0 ) =0 ,xg(x) >0 ,  x≠ 0 . ( 2 )Therehavebeenmanystudiesforlocalandglobalpropertiesofsolutionsforsystem ( 1 ) ,see[1 -9] .SetC+=(x,y)|h(y…  相似文献   
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