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111.
Oleg T. Izhboldin 《manuscripta mathematica》2000,102(1):41-52
Let F be a field of characteristic ≠2 and φ be a quadratic form over F. By X
φ we denote the projective variety given by the equation φ=0. For each positive even integer d≥8 (except for d=12) we construct a field F and a pair φ, ψ of anisotropic d-dimensional forms over F such that the Chow motives of X
φ and X
ψ coincide but . For a pair of anisotropic (2
n
-1)-dimensional quadrics X and Y, we prove that existence of a rational morphism Y→X is equivalent to existence of a rational morphism Y→X.
Received: 27 September 1999 / Revised version: 27 December 1999 相似文献
112.
High efficiency Al-free InGaAs/InGaAsP/InGaP lasers emitting at 980nm are fabricated by MOCVD. The lasers exhibit a high internal quantum efficiency of 95 % and a low internal loss of 1.8 cm-1. Low threshold current density of 190A/cm2 and high slope efficiency of 1.06W/A are obtained by lasers with 800μm cavitylength. A high characteristic temperature 210C is also obtained by replacing the GaAs barrier with high-bandgap InGaAsP barrier. The measured vertical and parallel divergence angle are 40° and 8°, respectively. 相似文献
113.
Bernd Süssmann 《Differential Geometry and its Applications》2011,29(1):1-6
In this paper the classical Banchoff-Pohl inequality, an isoperimetric inequality for nonsimple closed curves in the Euclidean plane, involving the square of the winding number, is sharpened for homothetic or Abresch-Langer solutions of curve shortening. For a larger class of curves and for rotationally symmetric curves, further isoperimetric inequalities containing the rotation number and the winding number, are presented. 相似文献
114.
Roberto Aravire Ahmed Laghribi Manuel ORyan 《Journal of Pure and Applied Algebra》2019,223(1):439-457
Let F be a field of characteristic 2. In this paper we give a complete computation of the kernel of the homomorphism induced by scalar extension, where is a purely inseparable extension (of any degree), is the cokernel of the Artin–Schreier operator given by: , where is the space of absolute m-differential forms over F and d is the differential operator. Other related results are included. 相似文献
115.
Valeri Obukhovskii 《Nonlinear Analysis: Theory, Methods & Applications》2010,73(6):1715-1728
We consider a semilinear functional differential inclusion with infinite delay and impulse characteristics in a Banach space assuming that its linear part is a non-densely defined Hille-Yosida operator. We assume that the multivalued nonlinearity of upper Carathèodory or almost lower semicontinuous type satisfies a regularity condition expressed in terms of the measures of noncompactness. We apply the theory of integrated semigroups and the theory of condensing multivalued maps to obtain local and global existence results. The application to an optimization problem for an impulsive feedback control system is given. 相似文献
116.
Guohua Peng 《Journal of Number Theory》2003,98(2):221-227
In this paper, we give a definition of genus field of function field with one variable over finite fields. And we explicitly describe the genus fields of Kummer function fields. For quadratic function fields case, our results are analogous to the genus fields of quadratic number fields. 相似文献
117.
118.
We show that for each p∈(0,1] there exists a separable p -Banach space Gp of almost universal disposition, that is, having the following extension property: for each ε>0 and each isometric embedding g:X→Y, where Y is a finite-dimensional p-Banach space and X is a subspace of Gp, there is an ε -isometry f:Y→Gp such that x=f(g(x)) for all x∈X. 相似文献
119.
We show that the transfinite inductive dimensions modulo PP-trind and P-trInd introduced in M.G. Charalambous (1997) [2] differ by simple spaces, where P is the absolutely additive Borel class A(α) or the absolutely multiplicative Borel class M(α), 0?α<ω1. 相似文献
120.
M.J. de la Puente 《Linear algebra and its applications》2011,435(7):1681-1795