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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.
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   

4.
51.IntroductionSupposethatr>Oisafixednumberand[oldenotes,asusuaI,theintegralpartofo.LetForo1wasfirststudiedin1953byPjateckii-Sapiro[']whoprovedthat(1.1)holdsfor1相似文献   

5.
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   

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.
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   

8.
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   

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.
51.IntroductionSpecialLagrangiansubmanifoldsofaCalabi-Yaumanifoldareoneoftherecentattractivesubjectsinmathematics(see[5-81).In1996,R.C.Mclean[7]obtainedthedeformationtheoremofspeciaILagrangiansubmanifold,whichshowsthat,givenonecompactspecialLagrangiansubmanifoldL,thereisalocalmodulispaceMlwhichisamanifoldandwhosetangelltspaceatLiscanonicallyidentifiedwiththespaceofharmonic1-formsonL.TheLzinnerproductonharmonicformsthengivesthemodulispaceanaturalRiemannianmetric.Strominger,YauandZaslow[1…  相似文献   

11.
A Remark on the Positive Definite Problem of a Binary Quartic Form   总被引:4,自引:0,他引:4  
凌生智 《数学季刊》1999,14(1):43-46
§1. IntroductionInthestudyofdifferentialequationsandothermathematicalfields,oneusuallyneedtodealwiththepositivedefinite,negativedefiniteproblemsofbinaryquarticforms,see[1,2].Itiswell-knowthatinthecaseofquadraticform,thereexistmanycriterionsfortheposi…  相似文献   

12.
While the solution to deriving the roots of the general quadratic equation is adequately covered in a typical classroom environment, the same is not true for the general cubic and quartic equations. To the best of our knowledge, we do not see the roots of the general cubic or quartic equation discussed in any typical algebra textbook at the undergraduate level. In this paper, we propose an efficient algorithm in order to calculate the roots of the general quadratic, cubic and quartic equations. Examples are given to demonstrate the usefulness of this proposed algorithm.  相似文献   

13.
In his paper [1], one of us has introduced a method for constructing integrable conservative two-dimensional mechanical systems, on Riemannian 2D spaces, whose second integral is a polynomial in the velocities. This method was applied successfully in [2] to construction of systems admitting a cubic integral and in [3, 4] and [5] to cases of a quartic integral. The present work is devoted to construction of new integrable systems with a quartic integral. The potential is assumed to have the structure
This is inspired by the structure of potential in the famous generalization of Kovalevskaya’s case in rigid body dynamics introduced by Goriatchev. The resulting differential equations were completely solved only for time reversible systems. A 10-parameter family of systems of the searched type is obtained. Four parameters determine the structure of the line element of the configuration manifold and the others contribute only to the potential function. In the case of time-irreversible systems the governing equations were solved in the three cases when the metric is identical to that of reduced rigid body motion. Those lead to three new several-parameter generalizations of known cases, including the classical cases of Kovalevskaya, Chaplygin and Goriatchev.   相似文献   

14.
丢番图方程aX~4-bY~2=1   总被引:1,自引:0,他引:1  
袁平之  张中峰 《数学学报》2010,53(3):443-454
应用Thue-Siegel方法,我们证明:对任意正整数a,b,不定方程aX~4-bY~2=1至多只有两组正整数解(X,Y),这证实了Walsh提的一个猜测.  相似文献   

15.
In this paper, we construct an infinite explicit family of genus one quartic curves with negative discriminants that are counterexamples to the Hasse principle explained by the Brauer–Manin obstruction.  相似文献   

16.
Phase retrieval refers to recovering a signal from its Fourier magnitude. This problem arises naturally in many scientific applications, such as ultra-short laser pulse characterization and diffraction imaging. Unfortunately, phase retrieval is ill-posed for almost all one-dimensional signals. In order to characterize a laser pulse and overcome the ill-posedness, it is common to use a technique called Frequency-Resolved Optical Gating (FROG). In FROG, the measured data, referred to as FROG trace, is the Fourier magnitude of the product of the underlying signal with several translated versions of itself. The FROG trace results in a system of phaseless quartic Fourier measurements. In this paper, we prove that it suffices to consider only three translations of the signal to determine almost all bandlimited signals, up to trivial ambiguities. In practice, one usually also has access to the signal's Fourier magnitude. We show that in this case only two translations suffice. Our results significantly improve upon earlier work.  相似文献   

17.
证明了具有退化四次曲线解[y-(x-1)2]2=0的Kolmogorov三次系统是可以存在极限环的.并举出了具体的例子.  相似文献   

18.
In this paper, we prove some stability results concerning the generalized quadratic and quartic type functional equation in the context of non-Archimedean fuzzy normed spaces in the spirit of Hyers-Ulam-Rassias. As applications, we establish some results of approximately generalized quadratic and quartic type mapping in non-Archimedean normed spaces. Also, we show that the assumption of the non-Archimedean absolute value of $2$ is less than $1$ cannot be omitted in our corollaries. The results improve and extend some recent results.  相似文献   

19.
一种四次有理插值样条及其逼近性质   总被引:3,自引:0,他引:3  
1引言有理样条函数是多项式样条函数的一种自然推广,但由于有理样条空间的复杂性,所以有关它的研究成果不象多项式样条那样完美,许多问题还值得进一步的研究.近几十年来,有理插值样条,特别是有理三次有理插值样条,由于它们在曲线曲面设计中的应用,已有许多学者进行了深入研究,取得了一系列的成果(见[1]-[7]).但四次有理插值样条由于其构造所花费的计算量太大以及在使用上很不方便而让人们忽视了其重要的应用价值,因此很少有人研究他们.实际上,在某些情况下四次有理插值样条有其独特的应用效果,如文[8]建立的一种具有局部插值性质的分母为二次的四次有理样条,即一个剖分  相似文献   

20.
Diophantine方程y~2=px(x~2+2)   总被引:2,自引:0,他引:2  
陈历敏 《数学学报》2010,53(1):83-86
设p是大于3的奇素数.本文证明了:当p≡5或7(mod 8)时,方程y~2=px(x~2+2)无正整数解(x,y);当p≡1(mod 8)时,该方程至多有1组解;当p≡3(mod 8)时,该方程至多有2组解.  相似文献   

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