
StatusThe thesis was presented on the 7 July, 2017 at the meeting of the Scientific Council and now it is under consideration of the National Council.Abstract– 0.65 Mb / in romanianThesisCZU 512.548
1.79 Mb /
in romanian 
The language of the Thesis is Romanian. It comprises 117 base pages and has the following structure: Introduction, 3 Chapters, General Conclusions and Recommendations, Bibliography with 142 References and an annex. Research outcomes were reflected in 20 scientific publications.
Field of study: theory of binary and ary quasigroups.
The purpose and objectives. The purpose of the Thesis is to describe the orthogonal systems consisting of three ternary quasigroups and ternary selectors, admitting at least one nontrivial paratopy. To achieve this purpose the following objectives are established: the founding of all such systems, the characterization of paratopies of these systems, the study of the identities implied by paratopies and the parastrophicorthogonal (selforthogonal) quasigroups of different arity, satisfying such identities.
Novelty and scientific originality. In the present Thesis, for the first time, there are determined all orthogonal systems consisting of three ternary quasigroups and ternary selectors, admitting at least one nontrivial paratopy and all paratopies of these systems are described; all identities implied by the paratopies are found and classified. The description of orthogonal systems consisting of three ternary quasigroups and ternary selectors, admitting at least one nontrivial paratopy, is a generalization of the V. Belousov result about the paratopies of orthogonal systems consisting of two binary quasigroups and binary selectors. For this purpose a general method was used, which can be applied for any finite arity. Estimations of the spectra of selforthogonal ary quasigroups are obtained, binary and ternary quasigroups with identities which imply the orthogonality of their parastrophes are studied.
The main solved scientific problem consists in describtion of orthogonal systems of three ternary quasigroups and ternary selectors, admitting at least one nontrivial paratopy.
The significance of theoretical and practical values of the work. The results concerning the description of the paratopies of orthogonal systems of quasigroups represent an important step in the study of the transformations of orthogonal systems of ary operations and of the identities implying the orthogonality of parastrophes of an ary quasigroup.
Implementation of the scientific results. Orthogonal systems of nquasigroups, n≥2, are used in the theory of MDScodes, in criptography, planning experiments, in combinatorics, in the theory of algebraic knets etc. The results may be applied as a support for teaching courses in higher education.