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1.

This paper introduces Hamel’s formalism for classical field theories with the goal of analyzing the dynamics of continuum mechanical systems with velocity constraints. The developed formalism is utilized to prove the existence and uniqueness of motions of an infinite-dimensional generalization of the Chaplygin sleigh, a canonical example of nonholonomic dynamics. The formalism is very flexible and, for mechanical field theories, includes the Eulerian and Lagrangian representations of continuum mechanics as special cases. It also provides a useful approach to analyzing symmetry reduction.

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2.
The Ramanujan Journal - In this paper, we prove six Ramanujan’s modular equations of septic degree by employing Ramanujan’s $$_1\psi _1$$ summation formula and certain theta function...  相似文献   

3.
We prove Khinchin’s Theorems for Gelfand pairs (G, K) satisfying a condition (*): (a)G is connected; (b)G is almost connected and Ad (G/M) is almost algebraic for some compact normal subgroupM; (c)G admits a compact open normal subgroup; (d) (G,K) is symmetric andG is 2-root compact; (e)G is a Zariski-connectedp-adic algebraic group; (f) compact extension of unipotent algebraic groups; (g) compact extension of connected nilpotent groups. In fact, condition (*) turns out to be necessary and sufficient forK-biinvariant measures on aforementioned Gelfand pairs to be Hungarian. We also prove that Cramér’s theorem does not hold for a class of Gaussians on compact Gelfand pairs. This author was supported by the European Commission (TMR 1998–2001 Network Harmonic Analysis).  相似文献   

4.
In this paper we show that some versions of Dung’s abstract argumentation frames are equivalent to classical propositional logic. In fact, Dung’s attack relation is none other than the generalised Peirce–Quine dagger connective of classical logic which can generate the other connectives ?, ù, ú, ?{\neg, \wedge, \vee, \to} of classical logic. After establishing the above correspondence we offer variations of the Dung argumentation frames in parallel to variations of classical logic, such as resource logics, predicate logic, etc., etc., and create resource argumentation frames, predicate argumentation frames, etc., etc. We also offer the notion of logic proof as a geometrical walk along the nodes of a Dung network and thus we are able to offer a geometrical abstraction of the notion of inference based argumentation. Thus our paper is also a contribution to the question:  相似文献   

5.
We prove the existence of global classical solutions to the initial value problem for the nonlinear Schrödinger equation, iut–u+q(|u|2)u=0 in iut - u + (|u|2)u = in (t, x)xn for 6n11.  相似文献   

6.
Paltin Ionescu 《代数通讯》2013,41(12):5088-5094
In classical projective algebraic geometry, ?n was seen mainly as a linear subspace. The modern setting has produced in the last 40 years several remarkable abstract characterizations of projective space. We survey some interaction between these two points of view.  相似文献   

7.
《偏微分方程通讯》2013,38(11-12):1863-1885
Abstract

The Nordström-Vlasov system describes the dynamics of a self-gravitating ensemble of collisionless particles in the framework of the Nordström scalar theory of gravitation. We prove existence and uniqueness of classical solutions of the Cauchy problem in three dimensions and establish a condition which guarantees that the solution is global in time. Moreover, we show that if one changes the sign of the source term in the field equation, which heuristically corresponds to the case of a repulsive gravitational force, then solutions blow up in finite time for a large class of initial data. Finally, we prove global existence of classical solutions for the one dimensional version of the system with the correct sign in the field equation.  相似文献   

8.
Letisthehypersurfaceofthirdclassicaldomainnlll(Ref.[l]),whereWhichisinvariantunderthelineartransformationW=ATA',AJ=JA,whereAllisannxnuppertriangularmatrixwithpositivediagonalelements,A12isannxnuppertriangularmatrixwithzerodiagonalelements.SuchtransformationsformaLiegroupSglll.whichisequivalenttoHnlllunderthemapdefinedbyW=AAI.TheAiscalledthehorohypercirclecoordinateofHnlll.Itiswell-knownthatinHnlllthereisaninvariantmetricInSnlll,whichisequaltothemetricdsZ~fir[(Z--'dZ)'l,inthehoro-hyp…  相似文献   

9.
The measure of non-compactness is estimated from below for various operators, including the Hardy-Littlewood maximal operator, the fractional maximal operator and the Hilbert transform, all acting between weighted Lebesgue spaces. The identity operator acting between weighted Lebesgue spaces and also between the counterparts of these spaces with variable exponents is similarly analysed. These results enable the lack of compactness of such operators to be quantified.  相似文献   

10.
L3t[1]istherealsecondclassicaldomains.ThemapdefinedbyW~(I T)--'(I--T)carriesRillontotheunboundeddomainWhichisinvariantfinderthelineartransformationW=ATA',whereAisannxnupertrianglarmatrixwithpositivediagonalelements.SuchtransformationsformaLiegroupRill(n),whichisequivalenttoRillunderthemapdefinedbyW=AA'.TheAiscalledthehoro-hypercirclecoordinateofRRII.Itiswell-knownthatinRillthereisanillvariantmetricdsZ=tr[(I--KW)--'dW]'.InRHI,,whichisequaltothemetricdsZ=fir[(W--'dW)'].Inthehoro-h…  相似文献   

11.
OntheLeftClassicalQuotientRingsoftheSuperprimeRingsChenPeici(陈培慈)(Dept.ofMath.JiangxiNormalUniversity,Nanchang,JiangxiPorvinc...  相似文献   

12.
殷在元 《数学季刊》1998,13(2):41-43
In[1],ZhengXueanprovedthat:letRI(n×n)befirstclassicaldomain,Unbecharacteris-ticboundaryofRI,x∈Un,f(x)∈L2(Un).Asz=rx(0≤r<1)→x,Cauchyintegral∫Unf(y)det(I-zy′)-ndyconvergetoafunctioninL2(Un).Inthispaper,wewillfacusourselfonCauchyintegralofL2onclassicaldomains[2]andgetsomeproperties.Themainresultisfollowing:Theorem LetRbeoneofclassicaldomains,LbecharacteristicboundaryofR,f∈L2(L),H(z,ξ)beCauchykernelofRandF(z)=∫Lf(u)H(z,u)u z∈R,(1)wheretherightisLebesgueintegral;uist…  相似文献   

13.
We consider a free boundary problem modeling fluid flow in a partially saturated porous media. In that context an unknown function represents the pressure and satisfies an elliptic equation in the saturated domain and a quasilinear parabolic equation in the unsaturated domain. The principal part of this work is the investigation of the smoothness properties of an unknown (free) boundary between domains of ellipticity and parabolicity.   相似文献   

14.
We study the local properties of eigenvalues for the Hermite (Gaussian), Laguerre (Chiral), and Jacobi β-ensembles of N×N random matrices. More specifically, we calculate scaling limits of the expectation value of products of characteristic polynomials as N→∞. In the bulk of the spectrum of each β-ensemble, the same scaling limit is found to be $e^{p_{1}}{}_{1}F_{1}$ , whose exact expansion in terms of Jack polynomials is well known. The scaling limit at the soft edge of the spectrum for the Hermite and Laguerre β-ensembles is shown to be a multivariate Airy function, which is defined as a generalized Kontsevich integral. As corollaries, when β is even, scaling limits of the k-point correlation functions for the three ensembles are obtained. The asymptotics of the multivariate Airy function for large and small arguments is also given. All the asymptotic results rely on a generalization of Watson’s lemma and the steepest descent method for integrals of Selberg type.  相似文献   

15.
16.
A new method for constructing the symmetric form for the hyperbolic systems is introduced. Then a new symmetric form of the equations of MHD transverse flow is constructed by adding an additional equation. With this new form, we obtain the local existence of smooth solution including the case that the initial density may tend to the vacuum state at infinity. Furthermore, the uniformly a priori estimation for the classical solutions is established and the global smooth solutions for a kind of initial data are obtained.  相似文献   

17.
18.
In this paper, we discuss the classical risk process with stochastic return on investment. We prove some properties of the ruin probability, the supremum distribution before ruin and the surplus distribution at the time of ruin and derive the integro-differential equations satisfied by these distributions respectively.  相似文献   

19.
BreakdownofClassicalSolutionsforQuasilinearHyperbolicSystemsofDiagonalForm¥LiDazhi(李大治)(NantongMedicalCollege)Abstract:Inthis...  相似文献   

20.
In this paper, we study the classical problem of the exponentially small splitting of separatrices of the rapidly forced pendulum. Firstly, we give an asymptotic formula for the distance between the perturbed invariant manifolds in the so-called singular case and we compare it with the prediction of Melnikov theory. Secondly, we give exponentially small upper bounds in some cases in which the perturbation is bigger than in the singular case and we give some heuristic ideas how to obtain an asymptotic formula for these cases. Finally, we study how the splitting of separatrices behaves when the parameters are close to a codimension-2 bifurcation point.  相似文献   

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