We prove two existence theorems for the integrodifferential equation of mixed type: x′(t) = f (t,x(t), t0k1(t,s)g(s,x(s))ds, ∫ a 0k2(t,s)h(s,x(s))ds), x(0) = x0, where in the first part of this paper f , g, h, x are functions with values in a Banach space E and integrals are taken in the sense of Henstock-Kurzweil (HK). In the second part f , g, h, x are weakly-weakly sequentially continuous fu...

a subgroup x of a group g is said to be an h -subgroup if n_g(x) ∩ x^g ≤ x for each element g belonging to g. in [m. bianchi e. a., on finite soluble groups in which normality is a transitive relation, j. group theory, 3 (2000), 147–156] the authors showed that finite groups in which every subgroup has the h -property are exactly soluble groups in which normality is a transitive relation. here ...

Let E be a real q-uniformly smooth Banach space whose duality map is weakly sequentially continuous. Let T : E → E be a nonexpansive mapping with F (T ) 6= ∅. Let A : E → E be an η-strongly accretive map which is also κ-Lipschitzian. Let f : E → E be a contraction map with coefficient 0 < α < 1. Let a sequence {yn} be defined iteratively by y0 ∈ E, yn+1 = αnγf(yn) + (I − αnμA)Tyn, n ≥ 0, where ...

Let Tf denote the Toeplitz operator with symbol function f on the Bergman space La(B, dv) of the unit ball in C . It is a natural problem in the theory of Toeplitz operators to determine the norm closure of the set {Tf : f ∈ L∞(B, dv)} in B(La(B, dv)). We show that the norm closure of {Tf : f ∈ L∞(B, dv)} actually coincides with the Toeplitz algebra T , i.e., the C∗-algebra generated by {Tf : f...

We consider the motion of a particle in a weak mean zero random force field F, which depends on the position, x(t), and the velocity, v(t) = 2(0. The equation of motion is 2(0 = ef(x( t ) , v(t), 0~), where x( ') and v(-) take values in R d, d > 3, and co ranges over some probability space. We show, under suitable mixing and moment conditions on F, that as e--+ 0, v~( t ) v(t/e 2) converges wea...

For any set-endofunctor T : Set→ Set there exists a largest subcartesian transformation μ to the filter functor F : Set → Set. Thus we can associate with every T -coalgebra A a certain filter-coalgebra AF. Precisely, when T weakly preserves preimages, μ is natural, and when T weakly preserves intersections, μ factors through the covariant powerset functor P, thus providing for every T -coalgebr...

a one-sided ideal of a ring has the insertion of factors property (or simply, ifp) if implies r for . we say a one-sided ideal of has the weakly ifp if for each , implies , for some non-negative integer . we give some examples of ideals which have the weakly ifp but have not the ifp. connections between ideals of which have the ifp and related ideals of some ring extensions are also shown.

In this paper, we investigate the uniqueness problem of differential–difference polynomials $$(f^{n}(z)P(f)L_c(f))^{(k)}$$ and $$(g^{n}(z)P(g)L_c(g))^{(k)}$$ sharing a small function under notion weakly weighted relaxed sharing, where $$L_c(f)=f(z+c)+c_0f(z)$$ , P(z) is polynomial with constant coefficients degree m, obtained corresponding results, which improve extend some recent results due t...