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1.
61.IntroductionThefixedPOinttheoremsofmixedmonotoneoperatorsaregotinpaper[1jandF2j-Inthispaper,regularconeanddemicontinuousofoperatorareweakenedinTheorem1ofpaper[1j.Theformerisweakenedtonormalconeandthelattertoweakerandweakercontinuous.Separabilityandweaklysequentiallycompactofimagesetofoperatorareweakenedtoquasi-separabilityandquasiweaklysequentiallycompactinTheorem1ofpaper[2j,Westillget'thefixedpointtheoremsofmixedmonotoneoperators.Wea1sogiveson1eapplicationstono11-monoteoperatorsanddiffe…  相似文献   

2.
梁俊奇  张志宏  赵玲 《数学季刊》2003,18(3):264-270
§ 1. Introduction  Anecessaryandsufficientconditionandasufficientconditiontoensurethataset valuedmappingandasingle valuedmappinginacompletemetricspaceandacompleteconvexmetricspacehavingacommonfixedpointarerespectivelygivenin [1 ] .Meanwhilethemainresultsin[2 ]— [5]areimprovedandextendedin [1 ] .Inthispaper ,theexistenceatcommonfixedpointsoftwoset valuedmappingandasing valuedmappingwerestudied ,andthecorrespond ingresultsin [1 ]— [5]wereextendedandimproved .Let(X ,d)beanon emptymetricspa…  相似文献   

3.
51.IntroductionSupposethatr>Oisafixednumberand[oldenotes,asusuaI,theintegralpartofo.LetForo1wasfirststudiedin1953byPjateckii-Sapiro[']whoprovedthat(1.1)holdsfor1相似文献   

4.
STABILIZATION OF VIBRATING BEAM BY VELOCITY FEEDBACK CONTROL   总被引:1,自引:0,他引:1  
1IntroductionInrecentyearstherehasbeenmuchinterestintopicofcontrolandstabilizationofflexiblevibratingsystemdescribedbyaEuler-Bernoullibeamequationasfollowing(See[1]-[8]).Thequestionofstabilizationofsystem(1.O)hasbeenstudiedbymanyauthors.Forexample,seeLagnese[1],Chen.et.al[2],R.b.,b.,l3]forstabilization,Lagllese[5]forconcentratedS/A'sstabilization.Letusmentionthatthesepapersstudyasymptoticoruniformdecayforthecollsideredsystem,butnotprovetheoptimalityofthedecayrate.C..,.d[8]studytheoptimali…  相似文献   

5.
1.IntroductionTheproblemsofinfinitesimalrigidityandisometricdeformationhavebeenextensivelyin-vestigatedforsurfacesinthreedimensionalEuclideanspaceE'.See,forexample,A.SvecL1]'E.Kann[2j,ZhouJiazu[3Jandthepapers[4j,[5J,[6JbyYangWenmao3also,KobayashiandNomizu[7].ThefirstauthorandZhangGaoyonggeneralizedthetheoryofinfinitesimali-sometriesofsurfacesinE3tothehypersurfacesimmersedinaspaceofconstantcurvature[8j.K.Tenenblat[9]andR.A.GoldsteinandP.J.Ryan[1o]studiedtheinfinitesimalI-isometryfors…  相似文献   

6.
MASLOV-TYPE INDEX THEORY FOR SYMPLECTIC PATHS AND SPECTRAL FLOW (II)   总被引:4,自引:0,他引:4  
1.IntroductionandMainResultsStartingfromthepioneeringworks[5,61ofH.AmannandE.Zehnderin1980,C.ConleyandE.Zehnderestablishedanindextheoryin1984intheircelebratedwork[if]fornondegeneratepathsinSp(Zn)startedfromtheidentitymatrixwithn22.Thisindextheorywasextendedtothenondegeneratecaseofn~1byE.Zehnderandthefirstauthorin[28]of1990.ThisindextheoryforthedegenerateHamiltoniansystemswasestablishedbythefirstauthorin[21]of1990andC.Viterboin[34]of1990viadifferentmethods,andthenextendedtoalldegenerates…  相似文献   

7.
Supersemiprime Rings and Supersemiprime Radical   总被引:4,自引:1,他引:3  
张宪君  靳庭良 《数学季刊》1998,13(2):107-110
§1. IntroductionInthisrecentyears,theprimeringswithspecialpropertieshavebeenstudiedsomeau-thors,forexample,N.T.Groenewaldintroducedthecompletelyprimeringsandthecompletelyrimeradicalin[1].D.HandelmanandJ.Lawrencediscussedthestronglyprimeringsandthestronglyprimeradicalin[2].S.Veldsmanstudiedthesuperprimeringsandthesuperprimeradicalin[3].ZhangXianjunintroducedtheAbsolutelysemiprimeringsandtheabsolutelysemiprimeradicalandsoon.Theaimofthispaperistostudythesemiprimeringswithspecialpropertiesan…  相似文献   

8.
61.IntroductionSincethepoineeringworkofZariskil1o]therehavebeenmanypaperspublishedonthemodulinumberofplanecurvesingUlaritiesl5-9].TheproblemhowtocomputethemodulinumberattractsmWattentions[3'6-1o1.Asfarastheauthors'knowledgethemostgener-aJizedalgorithmistheworkof[3]whichdependsonthedivisiontheoremin[1,2].HerewegivealinearalgebraicproofoftheBriancon-Granger-Maisonobe,stheoremlwhichavoidstheDivisiontheorem.Sincethedivisiontheoremonlyholdsindimension2,itseemsquitehopefUlthattheproofherewil1beg…  相似文献   

9.
1IntroductionThegeometryofquadricsandHerntitianvarietiesinfinite-dimensionalprojectivespaceshasbeenstudiedbyE-J.F.Primrose[6],D.K.tw-Chaudhuri['l8],I.M.Chakravarti["'],andR.C-BoseandI-M-Ch.kravarti[1].Inl993,I.M.Chak.ava,ti[4]derivedsomeassociationschemesandcodesfromuondegenerateHerndtia-nvarieties.In[1o],weconstructedsomedriiliesofassociationschemesfromthesetofisotropicpointsinpseudo-symplecticspaces.Inthispaper5weconsiderdegenerateqlledricsandconstructafamilyoffour-classassociations…  相似文献   

10.
A NEW STEP-SIZE SKILL FOR SOLVING A CLASS OF NONLINEAR PROJECTION EQUATIONS   总被引:1,自引:0,他引:1  
1.IntroductionIn[11],aniterativeprojectionandcontraction(PC)methodforlinearcomplemen-taxityproblemswasproposed.Inpractice,thealgorithmbehaveseffectively,butintheorythesteP-sizecannotbeprovedtobeboundedawayfromzero.Sonostatementcanbemadeabouttherateofconvergence.AlthoughavariantoftheprimePCal-gorithmwithconstantstepsizeforlineaJrprogrammminghasalinearconvergence['1,itconvergesmuchslowerinparctice.In[1o],HeproposedanewsteVsizerulefortheprimePCalgorithmforthelinearprogrammingsuchthattheresul…  相似文献   

11.
In this paper, the Ext groups of Hardy modules over the polydisk algebra A(D^n) are calculated, Of particular importance is that the calculating of Ext-groups is closely related to harmonic analysis of polydisks. Finally, the authors point out that Ext-groups reveal rigidity of Hardy submodules over A(D^n) for n > 1.  相似文献   

12.
1.IntroductionAHilbertmoduleisaHilbertspaceHwhichisalsoamoduleoverafunctionalgebraA,i.e.,thereisanassociativebilinearmultiplicationAxHHwhichiscontinuousinbothvariables.ThefirstsystematicstudyofHilbertmodulesappearedinthemonographofDouglasandPoulsen[...  相似文献   

13.
We will consider the problem of which the products of composition and analytic Toeplitz operators would be bounded or compact on the Hardy space H2 and the Bergman space La2.  相似文献   

14.
Holger Reich 《K-Theory》2001,24(4):303-326
We construct a real valued dimension for arbitrary modules over the algebra of operators affiliated to a finite von Neumann algebra. Moreover we determine the algebraic K 0- and K 1-group and the L-groups of such an algebra. Mathematics Subject Classifications (2000): Primary 18F25; Secondary 46L10.  相似文献   

15.
If \mathfrakA{\mathfrak{A}} is a unital weak-* closed algebra of multiplication operators on a reproducing kernel Hilbert space which has the property \mathbbA1(1){\mathbb{A}_1(1)}, then the cyclic invariant subspaces index a Nevanlinna–Pick family of kernels. This yields an NP interpolation theorem for a wide class of algebras. In particular, it applies to many function spaces over the unit disk including Bergman space. We also show that the multiplier algebra of a complete NP space has \mathbbA1(1){\mathbb{A}_1(1)}, and thus this result applies to all of its subalgebras. A matrix version of this result is also established. It applies, in particular, to all unital weak-* closed subalgebras of H acting on Hardy space or on Bergman space.  相似文献   

16.
In this paper, we consider the Ext functor in the category
of Hilbert modules over the disk algebra. We characterize the group
as a quotient of operators and explicitly calculate
, where is a weighted Hardy space. We then use our results to give a simple proof of a result due to Bourgain.

  相似文献   


17.
《代数通讯》2013,41(8):2809-2825
Let k be a field and An(ω) be the Taft's n2-dimensional Hopf algebra. When n is odd, the Drinfeld quantum double D(An(ω)) of An(ω) is a ribbon Hopf algebra. In the previous articles, we constructed an n4-dimensional Hopf algebra Hn(p, q) which is isomorphic to D(An(ω)) if p ≠ 0 and q = ω?1 , and studied the irreducible representations of Hn(1, q) and the finite dimensional representations of H3(1, q). In this article, we examine the finite-dimensional representations of Hn(l q), equivalently, of D(An(ω)) for any n ≥ 2. We investigate the indecomposable left Hn(1, q)-module, and describe the structures and properties of all indecomposable modules and classify them when k is algebraically closed. We also give all almost split sequences in mod Hn(1, q), and the Auslander-Reiten-quiver of Hn(1 q).  相似文献   

18.
The boundedness and compactness of weighted composition operators on the Hardy space H2{{\mathcal H}^2} of the unit disc is analysed. Particular reference is made to the case when the self-map of the disc is an inner function. Schatten-class membership is also considered; as a result, stronger forms of the two main results of a recent paper of Gunatillake are derived. Finally, weighted composition operators on weighted Bergman spaces A2a(\mathbbD){\mathcal{A}^2_\alpha(\mathbb{D})} are considered, and the results of Harper and Smith, linking their properties to those of Carleson embeddings, are extended to this situation.  相似文献   

19.
Gao  Dongfang  Ma  Yao  Zhao  Kaiming 《中国科学 数学(英文版)》2022,65(11):2243-2254
Science China Mathematics - In this paper, we study irreducible non-weight modules over the mirror Heisenberg-Virasoro algebra $${\cal D}$$ , including Whittaker modules, $${\cal U}\left(...  相似文献   

20.
In this paper, we present algorithms of preorthogonal adaptive Fourier decomposition (POAFD) in weighted Bergman spaces. POAFD, as has been studied, gives rise to sparse approximations as linear combinations of the corresponding reproducing kernels. It is found that POAFD is unavailable in some weighted Hardy spaces that do not enjoy the boundary vanishing condition; as a result, the maximal selections of the parameters are not guaranteed. We overcome this difficulty with two strategies. One is to utilize the shift operator while the other is to perform weak POAFD. In the cases when the reproducing kernels are rational functions, POAFD provides rational approximations. This approximation method may be used to 1D signal processing. It is, in particular, effective to some Hardy Hp space functions for p not being equal to 2. Weighted Bergman spaces approximation may be used in system identification of discrete time‐varying systems. The promising effectiveness of the POAFD method in weighted Bergman spaces is confirmed by a set of experiments. A sequence of functions as models of the weighted Hardy spaces, being a wider class than the weighted Bergman spaces, are given, of which some are used to illustrate the algorithm and to evaluate its effectiveness over other Fourier type methods.  相似文献   

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