In this paper we consider the Procrustes problem on the manifold of orthogonal Stiefel matrices. Given matrices A 2 R mk , B 2 R mp , m p k, we seek the minimum of kA?BQk 2 for all matrices Q 2 R pk , Q T Q = I kk. We introduce a class of relaxation methods for generating minimizing sequences and ooer a geometric interpretation of these methods. Results of numerical experiments illustrating the...

Suppose that for an arbitrary function $f(x,y)$ of two discrete variables, we have the formal expansions. [f(x,y)=sumlimits_{m,n=0}^{infty }a_{m,n},P_{m}(x)P_{n}(y),] $$‎ ‎x^{m}P_{j}(x)=sumlimits_{n=0}^{2m}a_{m,,n}(j)P_{j+m-n}(x)‎,$$ ‎we find the coefficients $b_{i,j}^{(p,q,ell‎ ,‎,r)}$ in the expansion‎ $$‎ ‎x^{ell }y^{r},nabla _{x}^{p}nabla _{y}^{q},f(x,y)=x^{ell‎ ‎}y^{r}f^{(p,q)}(x,y) =sumli...

In this paper, we deal with soft lattice implication algebras based on fuzzy sets. Using the concepts of fuzzy (implicative) filters, (∈,∈∨q)fuzzy (implicative) filters and (∈,∈∨q)-fuzzy (implicative) filters, some characterizations for ∈-soft sets and q-soft sets to be (implicative) filteristic soft lattice implication algebras are established.

In this paper, we define the concept of an intuitionistic Q-fuzzy normal HX group and some related properties are investigated. We also define the level subsets of an intuitionistic Q-fuzzy normal HX group and discussed some of its properties. A few equivalent propositions of fuzzy HX group constituting an intuitionistic Q-fuzzy normal HX group are given.

The concepts of (∈ γ , ∈ γ ∨ q δ )-fuzzy bi-hyperideals and (∈ γ , ∈ γ ∨ q δ )-fuzzy quasi-hyperideals of a semihyperring are introduced, and some related properties of such (∈ γ , ∈ γ ∨ q δ )-fuzzy hyperideals are investigated. In particular, the notions of hyperregular semihyperrings and left duo semihyperrings are given, and their characterizations in terms of hyperideals and (∈ γ , ∈ γ ∨ q ...

In recent years, underactuated nonlinear dynamic systems trajectory tracking, such as space robots and manipulators with structural flexibility, has become a major field of interest due to the complexity and high computational load of these systems. Hierarchical sliding mode control has been investigated recently for these systems; however, the instability phenomena will possibly occur, especia...

and Applied Analysis 3 is Cauchy. If each Cauchy sequence is convergent, then the fuzzy norm is said to be complete, and the fuzzy normed space is called a fuzzy Banach space. Let X,N be a fuzzy normed space and Y,N ′ a fuzzy Banach space. For a given mapping f : X → Y , we use the abbreviation Df ( x, y ) : f ( 2x y ) f ( 2x − y 2f x − fx y − fx − y − 2f 2x , 2.1 for all x, y ∈ X. Recall Df ≡ ...