一个关于Fuzzy关系方程是否有解的等价判别定理

Fuzzy关系方程已经广泛地应用于Fuzzy综合评判、Fuzzy控制等领域。本文通过直接比较Fuzzy关系方程的系数与常数的大小,给出一个判别所给的Fuzzy关系方程是否有解的行之有效的简便方法,并且在有解时还给出求其最大解、极小解及解集的方法。     

完备Brouwer格上有限sup-inf合成Fuzzy关系方程解集的一些性质

主要对完备Brouwer格上sup-inf合成的Fuzzy关系方程的解作了深入的讨论.首先讨论了在完备Brouwer格中方程解的情况,并在有解时给出了求解所有极小解的方法.进一步,刻画了sup-inf合成Fuzzy关系方程解集的结构.     

区间值max-*模糊关系方程的完全解

给出了区间值max-*模糊关系方程最大解的形式;存在极小解的充要条件,进一步刻画了极小解的形式和极小解的个数,最后刻画了区间值max-*模糊关系方程的解集.     

sup-conjunctor合成模糊关系方程有惟一极小解的条件

讨论[0,1]格上sup-conjunctor合成模糊关系方程有惟一极小解与惟一解的问题。首先给出了sup-conjunctor合成模糊关系方程解集的性质及两个算子IT与LT.然后定义并给出了sup-conjunctor合成模糊关系方程的特征矩阵。最后通过特征矩阵给出sup-conjunctor合成模糊关系方程有惟一极小解与惟一解的充要条件。     

无限Fuzzy关系方程的解集

对(0,1)格上的无限Fuzzy关系方程,给出其可解的充要条件.利用可达解与不可达解的概念,给出方程存在可达解与不可达解的充要条件.进一步,在解集非空时,刻画了方程的解集的结构及性质.     

关于Fuzzy矩阵的广义逆

本文分别给出了Fuzzy矩阵存在广义{1,3}-逆、广义{1,4}-逆以及Moore-Penrose广义逆Fuzzy矩阵的一些充要条件。又得到求上述广义逆Fuzzy矩阵的一些公式。主要的结果有: 1.Fuzzy矩阵A的广义{1,3}-逆A~((1.3))(广义{1,4}-逆A~((1.4))存在的充要条件是Fuzzy关系方程有解。2.Fuzzy矩阵A的Moore-Penrose广义逆A~T存在的充要条件是Fuzzy关系方程均有解。3.如果B、C分别为Fuzzy关系方程的一个解,那么。     

解Fuzzy关系方程。■=

本文将给出有限论域U、V上的Fuzzy关系方程。■==a_1,a_2,…,a_n)∈U,=(b_1,b_2,…,b_n)∈V)有解的充要条件,有最小解的充要条件以及极小解个数等几个定理。本文所采用的符号与[1]的符号一致。     

模糊关系方程supi∈■T(a_i,x_i)=b的解

本文讨论[0,1]上sup-T合成模糊关系方程的解。这里,T为阿基米德t-模。首先给出方程解集非空的充分必要条件以及方程有极小解的条件,证明方程解集不空时每个解有极小解,然后描述方程的解集。     

[0,1]格上无限inf-αR合成Fuzzy关系方程的解集北大核心

在[0,1]格上讨论了无限inf-αR合成Fuzzy关系方程的解集问题,从方程的系数出发,给出了方程存在可达解和不可达解的充要条件。进一步,在解集非空时,刻画了方程解集的结构。     

求模糊关系方程一个极小解的算法

本文给出一种能寻找[0,1]格上模糊关系方程一个极小解的算法。该算法用最大解作为初始向量对定义在[0,1]格上解集非空的有限论域上模糊关系方程均能准确无误的求出一个极小解,我们分析了算法的复杂性并用算例进行了说明。     

Determining a Rotation of a Tetrahedron from a Projection

The following problem, arising from medical imaging, is addressed: Suppose that T is a known tetrahedron in ?³ with centroid at the origin. Also known is the orthogonal projection U of the vertices of the image ?T of T under an unknown rotation ? about the origin. Under what circumstances can ? be determined from T and U?     

Symmetry-based solution of a model for a combination of a risky investment and a riskless investment

Benth and Karlsen [F.E. Benth, K.H. Karlsen, A note on Merton's portfolio selection problem for the Schwartz mean-reversion model, Stoch. Anal. Appl. 23 (2005) 687-704] treated a problem of the optimisation of the selection of a portfolio based upon the Schwartz mean-reversion model. The resulting Hamilton-Jacobi-Bellman equation in 1+2 dimensions is quite nonlinear. The solution obtained by Benth and Karlsen was very ingenious. We provide a solution of the problem based on the application of the Lie theory of continuous groups to the partial differential equation and its associated boundary and terminal conditions.     

On a mapping of a projective space into a sphere

We obtain an exact estimate for the minimum multiplicity of a continuous finite-to-one mapping of a projective space into a sphere for all dimensions. For finite-to-one mappings of a projective space into a Euclidean space, we obtain an exact estimate for this multiplicity for n = 2, 3. For n ≥ 4, we prove that this estimate does not exceed 4. Several open questions are formulated.     

Approaching a vertex in a shrinking domain under a nonlinear flow

We consider here the homogeneous Dirichlet problem for the equation , in a noncylindrical domain in space-time given by . By means of matched asymptotic expansion techniques we describe the asymptotics of the maximal solution approaching the vertex x=0, t=T, in the three different cases p>1/2, p=1/2(vertex regular), p<1/2 (vertex irregular).     

Calculating a function of a matrix with a real spectrum

Let T be a square matrix with a real spectrum, and let f be an analytic function. The problem of the approximate calculation of f(T) is discussed. Applying the Schur triangular decomposition and the reordering, one can assume that T is triangular and its diagonal entries t_ii are arranged in increasing order. To avoid calculations using the differences t_ii ? t_jj with close (including equal) t_ii and t_jj, it is proposed to represent T in a block form and calculate the two main block diagonals using interpolating polynomials. The rest of the f(T) entries can be calculated using the Parlett recurrence algorithm. It is also proposed to perform some scalar operations (such as the building of interpolating polynomials) with an enlarged number of significant decimal digits.

     

Folding a surface to a polygon

A concept of folding for compact connected surfaces, involving the partition of the surface into combinatorially identical n-sided topological polygons, is defined. The existence of such foldings for given n and given surfaces is explored, with definitive results for the sphere and the torus. We obtain necessary conditions for the existence of such foldings in all other cases.Supported by Kuwait University Grant SM 043.