A contiguous derivation of radius and center of the insphere of a general tetrahedron is given. Therefore a linear system is derived. After a transformation of it the calculation of radius and center can be separated ...A contiguous derivation of radius and center of the insphere of a general tetrahedron is given. Therefore a linear system is derived. After a transformation of it the calculation of radius and center can be separated from each other. The remaining linear system for the center of the insphere can be solved after discovering the inverse of the corresponding coefficient matrix. This procedure can also be applied in the planar case to determine radius and center of the incircle of a triangle.展开更多
Let N be the Lie algebra of all n x n dominant block upper triangular matrices over a field F. In this paper, we explicitly describe all Lie triple derivations of N when char(F) ≠ 2. As an application, we character...Let N be the Lie algebra of all n x n dominant block upper triangular matrices over a field F. In this paper, we explicitly describe all Lie triple derivations of N when char(F) ≠ 2. As an application, we characterize Lie derivations of N when char(F) ≠ 2.展开更多
Boolean functions used in a cryptographic system should have high algebraic immunity to resist algebraic attacks. This paper presents a matrix method for constructing balanced Boolean functions achieving maximum algeb...Boolean functions used in a cryptographic system should have high algebraic immunity to resist algebraic attacks. This paper presents a matrix method for constructing balanced Boolean functions achieving maximum algebraic immunity.展开更多
文摘A contiguous derivation of radius and center of the insphere of a general tetrahedron is given. Therefore a linear system is derived. After a transformation of it the calculation of radius and center can be separated from each other. The remaining linear system for the center of the insphere can be solved after discovering the inverse of the corresponding coefficient matrix. This procedure can also be applied in the planar case to determine radius and center of the incircle of a triangle.
文摘Let N be the Lie algebra of all n x n dominant block upper triangular matrices over a field F. In this paper, we explicitly describe all Lie triple derivations of N when char(F) ≠ 2. As an application, we characterize Lie derivations of N when char(F) ≠ 2.
基金supported by the National Natural Science Foundation of China under Grant Nos.61070172 and 10990011the Strategic Priority Research Program of Chinese Academy of Sciences under Grant No. XDA06010702the State Key Laboratory of Information Security,Chinese Academy of Sciences
文摘Boolean functions used in a cryptographic system should have high algebraic immunity to resist algebraic attacks. This paper presents a matrix method for constructing balanced Boolean functions achieving maximum algebraic immunity.