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521.
学生综合素质评价是高校素质教育测量的重要侧面,其综合素质的概念、评价指标内容的确定、权重的分配及评价方法选定直接影响着学生评价的客观性和公正性,采用"三选"法概括评价指标,用矩阵法确定各指标的权重,利用五元联系数建立数学模型试行评价,最后算例表明了它的有效性和实用性. 相似文献
522.
523.
Peter De Maesschalck Vincent Naudot Jeroen Wynen 《Journal of Differential Equations》2018,264(2):1442-1474
We consider a heteroclinic connection in a planar system, between two symmetric hyperbolic saddles of which the eigenvalues are resonant. Starting with a normal form, defined globally near the connection, we normally linearize the vector field by using finitely smooth tags of logarithmic form. We furthermore define an asymptotic entry–exit relation, and we discuss on two examples how to deal with counting limit cycles near a limit periodic set involving such a connection. 相似文献
524.
Indranil Biswas 《代数通讯》2020,48(4):1452-1475
AbstractWe investigate relative connections on a sheaf of modules. A sufficient condition is given for the existence of a relative holomorphic connection on a holomorphic vector bundle over a complex analytic family. We show that the relative Chern classes of a holomorphic vector bundle admitting relative holomorphic connection vanish, if each of the fiber of the complex analytic family is compact and Kähler. 相似文献
525.
All real classical solutions of the SU(2) Yang-Mills theory with spherical symmetry in 4-dimensional Euclidean space are constructed
analytically and catalogued. The uniqueness of the solution of Belavinet al in possessing finite action is explicitly demonstrated. 相似文献
526.
The paper addresses the problem of how to ensure existence of blossoms in the context of piecewise spaces built from joining different extended Chebyshev spaces by means of connection matrices. The interest of this issue lies in the fact that existence of blossoms is equivalent to existence of B-spline bases in all associated spline spaces. As is now classical, blossoms are defined in a geometric way by means of intersections of osculating flats. In such a piecewise context, intersecting a number of osculating flats is a tough proposition. In the present paper, we show that blossoms exist if an only if Bézier points exist, which significantly simplifies the problem. Existence of blossoms also proves to be equivalent to existence of Bernstein bases. In order to establish the latter results, we start by extending to the piecewise context some results which are classical for extended Chebyshev spaces.
AMS subject classification 65D17, 65D07 相似文献
527.
We characterize – by describing in local coordinates their sections – the transversal bundles which on the complex hypersurface with type number 1 induce locally symmetric connections. 相似文献
528.
Given two closure spaces (E,) and (E,), a relation RE×E is said biclosed if every row of its matrix representation corresponds to a closed subset of E, and every column to a closed subset of E. An isomorphism between, on the one hand, the set of all biclosed relations and, on the other hand, the set of all Galois connections between the two lattices of closed sets is established. Several computational applications are derived from this result. 相似文献
529.
The Clay Millenium Problem on the mass gap for the QuantumYang-Mills Field Theory is commented upon. Particular emphasis
is put on the importance of the dimensional transmutation after the quantisation.
Received: 18 April 2002 相似文献
530.
This paper aims to classify the holonomy of the conformal Tractor connection, and relate these holonomies to the geometry of the underlying manifold. The conformally Einstein case is dealt with through the construction of metric cones, whose Riemannian holonomy is the same as the Tractor holonomy of the underlying manifold. Direct calculations in the Ricci-flat case and an important decomposition theorem complete the classification for definitive signature. 相似文献