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111.
A. Di Nola
W. Pedrycz
S. Sessa
E. Sanchez
《Fuzzy Sets and Systems》1991,40(3):415-429We give a wide overview on the applications of fuzzy relation equations theory to decision-making processes, to the construction of preference relations and to Knowledge Engineering, mainly fuzzy control and fuzzy pattern recognition. General theoretical results and methodological aspects are pointed out. 相似文献
112.
Logarithmic norms are often used to estimate stability and perturbation bounds in linear ODEs. Extensions to other classes of problems such as nonlinear dynamics, DAEs and PDEs require careful modifications of the logarithmic norm. With a conceptual focus, we combine the extension to nonlinear ODEs [15] with that of matrix pencils [10] in order to treat nonlinear DAEs with a view to cover certain unbounded operators, i.e. partial differential algebraic equations. Perturbation bounds are obtained from differential inequalities for any given norm by using the relation between Dini derivatives and semi-inner products. Simple discretizations are also considered. 相似文献
113.
本文在H lder范数生成的强拓扑下, 通过建立大偏差公式, 得到了k维布朗运动C-R型增量在H lder范数下的泛函极限定理. 相似文献
114.
Yuanqu Lin 《中国科学A辑(英文版)》1998,41(6):613-621
The existence of a bounded global attractor for a cross-diffusion model of forest with homogeneous Dirichlet boundary condition
is proved under some condition on the parameters
Project supported by the National Natural Science Foundation of China (Grant No. 19671005). 相似文献
115.
F. Pillichshammer 《Acta Mathematica Hungarica》2003,98(4):311-321
We ask for the maximum σ
n
γ
of Σ
i,j=1
n
‖x
i-x
j‖γ, where x
1,χ,x
n are points in the Euclidean plane R
2 with ‖xi-xj‖ ≦1 for all 1≦ i,j ≦ n and where ‖.‖γ denotes the γ-th power of the Euclidean norm, γ ≧ 1. (For γ =1 this question was stated by L. Fejes Tóth in [1].) We calculate
the exact value of σ
n
γ
for all γ γ 1,0758χ and give the distributions which attain the maximum σ
n
γ
. Moreover we prove upper bounds for σ
n
γ
for all γ ≧ 1 and calculate the exact value of σ
4
γ
for all γ ≧ 1.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
116.
O. I. Mokhov 《Theoretical and Mathematical Physics》2007,152(2):1183-1190
We prove that the associativity equations of two-dimensional topological quantum field theories are very natural reductions
of the fundamental nonlinear equations of the theory of submanifolds in pseudo-Euclidean spaces and give a natural class of
flat torsionless potential submanifolds. We show that all flat torsionless potential submanifolds in pseudo-Euclidean spaces bear natural structures
of Frobenius algebras on their tangent spaces. These Frobenius structures are generated by the corresponding flat first fundamental
form and the set of the second fundamental forms of the submanifolds (in fact, the structural constants are given by the set
of the Weingarten operators of the submanifolds). We prove that each N-dimensional Frobenius manifold can be locally represented
as a flat torsionless potential submanifold in a 2N-dimensional pseudo-Euclidean space. By our construction, this submanifold
is uniquely determined up to motions. Moreover, we consider a nonlinear system that is a natural generalization of the associativity
equations, namely, the system describing all flat torsionless submanifolds in pseudo-Euclidean spaces, and prove that this
system is integrable by the inverse scattering method.
To the memory of my wonderful mother Maya Nikolayevna Mokhova (4 May 1926–12 September 2006)
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 152, No. 2, pp. 368–376, August, 2007. 相似文献
117.
V. S. Monakhov 《Mathematical Notes》1997,61(5):585-589
Finite groups with 2-nilpotent subgroups of even index are described.
Translated fromMatematicheskie Zametki, Vol. 61, No. 5, pp. 700–705, May, 1997.
Translated by A. I. Shtern 相似文献
118.
探讨超收敛猜想中p=4的情形.为此目的我们推导了离散格林函数的权模估计. 相似文献
119.
利用矩阵的广义逆、奇异值分解、张量积和拉直算子,给出了矩阵方程AX=B有转动不变解的充分必要条件及有解时通解的表达式;给出了矩阵方程解集合中与给定矩阵的最佳逼近解的表达式. 相似文献
120.
单位球面间的等距延拓 总被引:6,自引:6,他引:0
本文证明了在一定条件下赋范线性空间与其共轭空间的单位球面之间的等距算子可以延拓为全空间的实线性等距算子。进而,刻画了光滑的自反空间的单位球面到其共轭空间的单位球面上的等距算子。 相似文献