Wyniki wyszukiwania - Biblioteka Nauki

1

Pochodne instrumenty finansowe w zarządzaniu ryzykiem w bankach korporacyjnych

100%

Gwizdała J.

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nr 4

37-49

PL

Pochodne instrumenty finansowe wprowadzono na globalnych rynkach finansowych w celu zmniejszenia ryzyka. Aktualnie wykorzystanie pochodnych instrumentów finansowych przez polskie banki korporacyjne dynamicznie wzrasta. Właściwe ich wykorzystanie umożliwia sprawne i skuteczne zarządzanie ryzykiem oraz przyczynia się do polepszenia kondycji finansowej banków. Banki wykorzystują instrumenty pochodne w celu zabezpieczenia się przed ryzykiem oraz dla jego ograniczenia i optymalizacji. Zarządzanie ryzykiem w banku stanowi integralną część zarządzania strategicznego instytucją finansową. Działania banków za pomocą instrumentów pochodnych są nierozerwalnym elementem ich polityki wewnętrznej.

2

Derivable maps and generalized derivations on nest and standard algebras

88%

Pan Z.

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tom Vol. 49, nr 3

331--344

EN

For an algebra A, an A-bimodule M, and m (…) M, define a relation on A by RA(m, 0) = {(a, b) (…) A x A : amb = 0}. We show that generalized derivations on unital standard algebras on Banach spaces can be characterized precisely as derivable maps on these relations. More precisely, if A is a unital standard algebra on a Banach space X then (…)L(A,B(X)) is a generalized derivation if and only if (..) is derivable on RA(M,0), for some M (…) B(X). We give an example to show this is not the case in general for nest algebras. On the other hand, for an idempotent P in a nest algebra A = algN on a Hilbert space H such that P is either left-faithful to N or right-faithful to N﬩, if δ (…)L(A, B)H)) is derivable on RA(P, 0) then δ is a generalized derivation.

3

Pairs of derivations on rings and Banach algebras

75%

Wei F. , Xiao Z.

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tom Vol. 41, nr 2

297-308

EN

We give a generalization of Vukman's theorem concerning a pair of derivations on rings. Then applying this purely algebraic result we obtain several range inclusion results of pair of derivations on Banach algebras.

4

Derivation with engel conditions on multilinear polynomials in prime rings

75%

Dhara B.

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2009

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tom Vol. 42, nr 3

467-478

EN

Let R be a prime ring with extended centroid C and characteristic different from 2, d a nonzero derivation of R, f(x1,..., xn) a nonzero multilinear polynomial over C such that [d2(f(x1,... , xn)),d(f(x1,... ,xn))]k = 0 for all x1,... ,xn in some nonzero right ideal [...] of R, where k is a fixed positive integer. If d(p) p [..]0, then pC = eRC for some idempotent e in the socle of RC and /(x1,..., xn) is central-valued on eRCe.

5

On (m, n)-derivations of some algebras

75%

Shen Q. , Li J. , Guo J.

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tom Vol. 47, nr 3

672--694

EN

Let A be a unital algebra, δ be a linear mapping from A into itself and m, n be fixed integers. We call δ an (m, n)-derivable mapping at Z, if mδ(AB) + nδ(BA) = mδ(A)B + mAδ(B) + nδ(B)A + nBδ(A) for all A, B (…) A with AB = Z. In this paper, (m, n)-derivable mappings at 0 (resp. IA (…) 0, I) on generalized matrix algebras are characterized. We also study (m, n)-derivable mappings at 0 on CSL algebras. We reveal the relationship between this kind of mappings with Lie derivations, Jordan derivations and derivations.

6

Generalized finite operators

75%

Mecheri S.

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tom Vol. 38, nr 1

163--167

EN

Let B(H) be the algebra of all bounded linear operators on an infinite dimensional complex and separable Hilbert space H. A infinity B(H) is called finite if \\AX - XA - I\\ > 1, VX infinity B(H). In this paper we extend the class of finite operators to a more general class of pairs of operators called generalized finite operators defined by {(A, B) infinity B(H) x B(H) : \\AX - XB - I\\ > 1, VX infinity B(H)} and we present some pairs of generalized finite operators.

7

Wykrywanie oraz identyfikacja przyspieszaczy i przeciwutleniaczy w wyrobach z gumy przeznaczonych do kontaktu z mlekiem

63%

Malcher E. , Tkacz J.

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tom 32

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nr 3

8

Genotoxicity of cyclopentha[c]phenanthrene and its two derivatives based on an in vitro micronucleus test

63%

Rudnicka K. , Łuczyński M. K. , Góra M.

Environmental Biotechnology

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2012

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tom Vol. 8, No. 2

63--66

EN

Environmental pollution causes a variety of health problems, including cancer. Many known pollutants have carcinogenic properties and polycyclic aromatic hydrocarbons (PAH) belong to this group. In this study, an in vitro culture of V79 cells of the Chinese hamster was subjected to three tested PAHs: 5-amino-2,3-dihydro-1H-cyclopenta-[c]phenanthrene (ACP[c]Ph), 5-amino-9-methoxy-2,3-dihydro-1H-cyclopenta[c]phenanthrene (AMCP[c]Ph) and cyclopenta[c]phenanthrene (CP[c]Ph). The in vitro micronucleus (MN) assay was applied in order to evaluate the genotoxic properties of the studied compounds. The highest genotoxic effect was observed for AMCP[c]Ph in a concentration of 0.02μg·ml-1. The genotoxic effect of the other two compounds was slightly lower.

9

Identities with generalized derivations in semiprime rings

63%

Dhara B. , Ali S. , Pattanayak A.

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tom Vol. 46, nr 3

453--460

EN

Let R be a semiprime ring. An additive mapping F:R  R is called a generalized derivation of R if there exists a derivation d : R  R such that F(xy) = F(x)y + xd(y) holds, for all x,y  R. The objective of the present paper is to study the following situations: (1) (...), for all x, y in some appropriate subset of R.

10

On some equations related to derivations in rings and Banach algebras

63%

Vukman J. , Kosi-Ulbl I.

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2006

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tom Vol. 39, nr 1

61-66

EN

The main purpose of this paper is to investigate additive mapping D : R -> R, where R is a (m + n +1)! and \m2 + n2 - m - n - 4mn\ -torsion free semiprime ring with the identity element, satisfying the relation 2D(xm+n+l) = (m+-n+1)(xmD(x)xn +-xnD(x)xm), for all is an element of R and some integers m > 1, n > 1, m2 + n2 - m - n - 4mn /=0.

11

Approximation of additive functional equations in NA Lie C*-algebras

63%

Wang Z. , Saadati R.

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tom Vol. 51, nr 1

37--44

EN

In this paper, by using fixed point method, we approximate a stable map of higher *-derivation in NA C*-algebras and of Lie higher *-derivations in NA Lie C*-algebras associated with the following additive functional equation [wzór], where m ≥ 2.

12

On derivations of operator algebras with involution

51%

Širovnik N. , Vukman J.

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tom Vol. 47, nr 4

784--790

EN

The purpose of this paper is to prove the following result. Let X be a complex Hilbert space, let L(X) be an algebra of all bounded linear operators on X and let A(X) (…) L(X) be a standard operator algebra, which is closed under the adjoint operation. Suppose there exists a linear mapping D : A(X) → L(X) satisfying the relation 2D(AA*A) = D(AA*)A + AA*D(A) + D(A)A*A + AD(A*A) for all A (…) A(X). In this case, D is of the form D(A) = [A,B] for all A (…) A(X) and some fixed B (…) L(X), which means that D is a derivation.

13

On alfa-derivations of prime and semiprime rings

51%

Vukman J.

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tom Vol. 38, nr 2

283--290

EN

In this paper we investigate identities with alfa-derivations on prime and semiprime rings. We prove, for example, the following result. If D : R - R is an alfa-derivation of a 2 and 3-torsion free semiprime ring R such that [D(x},x2] = 0 holds, for all x is an element of R, then D maps R into its center. The results of this paper are motivated by the work of Thaheem and Samman [20].