# Storozh O. G.

### Conditions for the maximal dissipativity of almost bounded perturbations of smooth restrictions of operators adjoint to symmetric ones

Ukr. Mat. Zh. - 2004. - 56, № 7. - pp. 966–976

We establish conditions for the maximal dissipativity of one class of densely-defined closed linear operators in a Hilbert space. The results obtained are applied to the investigation of some special differential boundary operators.

### A Differential Boundary Operator of the Sturm–Liouville Type on a Semiaxis with Two-Point Integral Boundary Conditions

Ukr. Mat. Zh. - 2002. - 54, № 11. - pp. 1480-1485

We prove that a differential boundary operator of the Sturm–Liouville type on a semiaxis with two-point integral boundary conditions that acts in the Hilbert space *L* _{2}(0, ∞) is closed and densely defined. The adjoint operator is constructed. We also establish criteria for the maximal dissipativity and maximal accretivity of this operator.

### On One Class of Almost Bounded Perturbations of Smooth Restrictions of a Closed Operator

Ukr. Mat. Zh. - 2002. - 54, № 10. - pp. 1396-1402

We investigate one class of perturbations of a closed densely-defined operator in a Hilbert space. These perturbations change the domain of definition of the operator. We prove that the perturbed operator *S* is closed and densely defined. We construct the adjoint operator *S**.

### On the conditions of solvability and the resolvent of a second-order deferential boundary operator in a space of vector functions

Ukr. Mat. Zh. - 1995. - 47, № 4. - pp. 517–524

A boundary differential operator generated by the Sturm-Liouville differential expression with bounded operator potential and nonlocal boundary conditions is considered. The conditions for a considered operator to be a Fredholm and solvable operator are established and its resolvent is constructed.

### Extremal extensions of a nonnegative operator, and accretive boundary-value problems

Ukr. Mat. Zh. - 1990. - 42, № 6. - pp. 858–860

### Accretive operators related to a positive-definite operator

Ukr. Mat. Zh. - 1989. - 41, № 6. - pp. 789–794

### Maximal dissipativity of ordinary boundary-differential and certain other operators

Ukr. Mat. Zh. - 1984. - 36, № 1. - pp. 78 - 82

### Operators satisfying smoothness conditions

Ukr. Mat. Zh. - 1982. - 34, № 4. - pp. 451—455

### Eigenfunction expansion of certain self-conjugate operators

Ukr. Mat. Zh. - 1976. - 28, № 3. - pp. 418–421