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1.
1 IntroductionThispaperisdevotedtostudywhatkindofdiscreteschemesofthefollowing 2n dimen sionalHamiltoniansystemswithparameterinnormalform u=J2n H uT,  H =H(u ,λ) ,(1 )whereu∈R2n,λ∈R ,H∈Ck+1(R2n×R ,R) ,k≥ 6,andJ2n =0In-In 0 ,In:unitmatrixofordernhasthepropertyofinheritinghom…  相似文献   
2.
Some of the blending interpolation methods (which) stated by a convex combination technique are presented. This includes C1 ,C2 blending triangular interpolanls and C1 -blending quadrilateral inter polanls for surfaces. The mentioned methods can be generalized to the construction of C" blending interpolants.  相似文献   
3.
State-of-the-art predictions for the Higgs-boson production cross section via gluon fusion and for all relevant Higgs-boson decay channels are presented in the presence of a fourth Standard-Model-like fermion generation. The qualitative features of the most important differences to the genuine Standard Model are pointed out, and the use of the available tools for the predictions is described. For a generic mass scale of 400−600 GeV in the fourth generation explicit numerical results for the cross section and decay widths are presented, revealing extremely large electroweak radiative corrections, e.g., to the cross section and the Higgs decay into WW or ZZ pairs, where they amount to about −50 % or more. This signals the onset of a non-perturbative regime due to the large Yukawa couplings in the fourth generation. An estimate of the respective large theoretical uncertainties is presented as well.  相似文献   
4.
Theaspirone (10 a,b) was isolated for the first time by Ina and Sakata2 in 1968. Although more than hundred compounds had been identified in tea flavour at that time none of them could be assigned to be responsible for its typical aroma. Ina et al. claimed that a 1:1 mixture of theaspirone and the lactone of 2-hydroxy-2,6,6-trimethyl-cyclohexylidene acetic acid3 had the fragrance of tea. Both compounds are found in this ratio in black tea in a total concentration of 30–40 ppb.  相似文献   
5.
In this paper, we consider the exterior problem of the critical semilinear wave equation in three space dimensions with variable coefficients and prove the global existence of smooth solutions. As in the constant coefficients case, we show that the energy cannot concentrate at any point (t, x) ∈ (0, ∞) ×Ω. For that purpose, following Ibrahim and Majdoub's paper in 2003, we use a geometric multiplier similar to the well-known Morawetz multiplier used in the constant coefficients case. We then use the compari...  相似文献   
6.
对带有控制-状态混合约束的一类受控时滞Volterra型积分系统,导出了其最优控制的一组必要条件和一组充分条件.  相似文献   
7.
In this paper we establish a large deviation principle for the occupation times of critical branching α-stable processes for large dimensions d > 2α, by investigating two related nonlinear differential equations. Our result is an extension of Cox and Griffeath’s (in 1985) for branching Brownian motion for d > 4.  相似文献   
8.
In this paper,we study the TE,TM model by using the decompositions of the vector fields in 2-D bounded multiply connected domains and 2-D unbounded domains,respectively.We find that the TE,TM model and the Darwin models are equivalent if we assume some regularity of the initial data.  相似文献   
9.
In this paper we give a certain classification theorem of extensions of the torus algebra up to isomorphism and also show that the K 0 -group K 0 (E) and the semigroup V (E) are two complete invariants of such extension algebras.  相似文献   
10.
By establishing the intrinsic super-Poincar'e inequality,some explicit conditions are presented for diffusion semigroups on a non-compact complete Riemannian manifold to be intrinsically ultracontractive.These conditions,as well as the resulting uniform upper bounds on the intrinsic heat kernels,are sharp for some concrete examples.  相似文献   
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