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排序方式: 共有188条查询结果,搜索用时 15 毫秒
31.
Nicola Mazzari 《代数通讯》2020,48(1):299-306
AbstractWe construct the (filtered) Ogus realization of Laumon 1-motives over a number field. This realization extends the functor defined on Deligne 1-motives by Andreatta, Barbieri-Viale and Bertapelle. 相似文献
32.
Completely J — positive linear systems of finite order are introduced as a generalization of completely symmetric linear systems. To any completely J — positive linear system of finite order there is associated a defining measure with respect to which the transfer function has a certain integral representation. It is proved that these systems are asymptotically stable. The observability and reachability operators obey a certain duality rule and the number of negative squares of the Hankel operator is estimated. The Hankel operator is bounded if and only if a certain measure associated with the defining measure is of Carleson type. We prove that a real symmetric operator valued function which is analytic outside the unit disk has a realization with a completely J — symmetric linear space which is reachable, observable and parbalanced. Uniqueness and spectral minimality of the completely J — symmetric realizations are discussed. 相似文献
33.
利用玻色振子的逆算符构造了SU(1,1)群的生成元和不可约表示的相干态,导出了SU(1,1)群的非齐次逆微分实现. 相似文献
34.
Adelio Matamala‐Vsquez Josep Planelles 《International journal of quantum chemistry》2000,77(4):704-709
A pure algebraic treatment of the eigenvalue equation corresponding to the asymmetric top is presented. The algebraic method employs the Holstein–Primakoff bosonic realization of the angular momentum algebra. Explicit determination of the linear boson transformation coefficients of the eigenstates is carried out by means of the coherent states formalism. No reference to special functions is needed and a completely algebraic approach is achieved. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 77: 704–709, 2000 相似文献
35.
A basic problem in the theory of simple games and other fields is to study whether a simple game (Boolean function) is weighted
(linearly separable). A second related problem consists in studying whether a weighted game has a minimum integer realization.
In this paper we simultaneously analyze both problems by using linear programming.
For less than 9 voters, we find that there are 154 weighted games without minimum integer realization, but all of them have minimum normalized realization. Isbell in 1958 was the first to find a weighted game without a minimum normalized
realization, he needed to consider 12 voters to construct a game with such a property. The main result of this work proves
the existence of weighted games with this property with less than 12 voters.
This research was partially supported by Grant MTM 2006-06064 of “Ministerio de Ciencia y Tecnología y el Fondo Europeo de
Desarrollo Regional” and SGRC 2005-00651 of “Generalitat de Catalunya”, and by the Spanish “Ministerio de Ciencia y Tecnología”
programmes ALINEX (TIN2005-05446 and TIN2006-11345). 相似文献
36.
共振隧穿二极管(RTD)可编程逻辑门是一种由单双稳态转换逻辑单元(MOBILE)及正、负输入分支组成的阈值逻辑电路。基于二进制神经元模型中的三层网络结构,提出了基于RTD可编程逻辑门的n变量函数实现算法。按照汉明距离由大到小的顺序,搜索最优输入向量,用定理1或定理2方法产生隐层函数,通过变换次数,确定输入向量的真假及隐层函数的权重。由于定义了最优输入向量及变换次数,提高了算法的准确性;又由于采用了定理2方法,令设计的电路更简单。 相似文献
37.
38.
New 3-mode bosonic operator realization of SU(2) Lie algebra: From the point of view of squeezing
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We consider the quantum mechanical SU(2) transformation e2λ JzJ± e-2λJz= e±2λJ± as if the meaning of squeezing with e±2λbeing squeezing parameter. By studying SU(2) operators(J±,Jz) from the point of view of squeezing we find that(J±,Jz) can also be realized in terms of 3-mode bosonic operators. Employing this realization, we find the natural representation(the eigenvectors of J+ or J-) of the 3-mode squeezing operator e2λ Jz. The idea of considering quantum SU(2) transformation as if squeezing is liable for us to obtain the new bosonic operator realization of SU(2) and new squeezing operators. 相似文献
39.
《Optimization》2012,61(8):969-987
The intensity modulated radiation therapy (IMRT) treatment planning problem is usually divided into three smaller problems that are solved sequentially: geometry problem, intensity problem and realization problem. There are many models and algorithms that address each one of the problems in a satisfactory way. However, these problems cannot be seen separately, because strong links exist between them. While the linkage between the geometry problem and the intensity problem is straightforward, the linkage between the intensity problem and the realization problem is all but simple and will determine the quality of the treatment planning. In practice, the linkage between these problems is, most of the times, done in a rather simple way, usually by rounding. This can lead to a significant deterioration of the treatment plan quality. We propose a combinatorial optimization approach to enable an improved transition from optimized to delivery fluence maps in IMRT treatment planning. Two clinical examples of head and neck cancer cases are used, both to present numerical evidences of the resulting deterioration of plan quality if a simplistic approach is used, and also to highlight a combinatorial optimization approach as a valuable alternative when linking the intensity problem and the realization problem. 相似文献
40.
The explicit expressions for indecomposable representations of nine square-root Lie algebras of vector type, Rνλ (ν, λ=0, ±1),
are obtained on the space of universal enveloping algebra of two-state Heisenberg-Weyl algebra, the invariant subspaces and the quotient spaces.
From Fock representations corresponding to these indecomposable representations, the inhomogeneous
boson realizations of Rνλ
are given. The expectation values of Rνλ in the angular momentum
coherent states are calculated as well as the corresponding classical limits. 相似文献