Results 1 to 10 of about 168,117,835 (293)
Quadratic forms associated to stratifying systems
Journal of Algebra, 2006 A well-known result of \textit{C. M. Ringel} [Tame algebras and integral quadratic forms. Lect. Notes Math. 1099 (1984; Zbl 0546.16013)] states that a representation-directed algebra is representation-finite. Moreover, if it possesses a sincere indecomposable module then the dimension vector map furnishes a bijection between the isomorphism classes of ...
Octavio Mendoza, Corina Saenz
exaly +2 more sources
UNCERTAIN SYSTEMS, BEHAVIOURS AND QUADRATIC DIFFERENTIAL FORMS [PDF]
IFAC Postprint Volumes IPPV / International Federation of Automatic Control, 2002 Abstract This paper considers uncertain systems from a behavioural point of view defined via quadratic differential forms. This uncertainty definition is closely related to the integral quadratic constraint uncertainty description commonly found in robust control theory.
Ian Petersen, Jan Camiel Willems
exaly +2 more sources
Synthesis of dissipative systems using quadratic differential forms: Part I [PDF]
IEEE Transactions on Automatic Control, 2002 In this second part of this paper, we discuss several important special cases of the problem solved in Part I. These are: disturbance attenuation and passivation, the full information case, the filtering problem, and the case that the to-be-controlled plant is given in input–state–output representation.
H L Trentelman, J C Willems
exaly +6 more sources
Quadratic Theory of Gravity with a Scalar Field and Type I Shapovalov Wave Spacetimes
Universe, 2022 For the quadratic theory of gravity with a scalar field, exact solutions are found for gravitational-wave models in Shapovalov I-type spacetimes, which do not arise in models of the general theory of relativity.
Konstantin Osetrin +2 more
doaj +1 more source
Systems of Hermitian Quadratic Forms [PDF]
Canadian Mathematical Bulletin, 2004 AbstractIn this paper, we give some conditions to judge when a system of Hermitian quadratic forms has a real linear combination which is positive definite or positive semi-definite. We also study some related geometric and topological properties of the moduli space.
Ma, Li, Chen, Dezhong
openaire +1 more source
Electronic Journal of Qualitative Theory of Differential Equations, 2021 During the last forty years the theory of integrability of Darboux, in terms of algebraic invariant curves of polynomial systems has been very much extended and it is now an active area of research.
Regilene Oliveira +3 more
doaj +1 more source
Mathematics, 2023 A positively invariant set is an important concept in dynamical systems. The study of positively invariant set conditions for discrete-time systems is one interesting topic in both theoretical studies and practical applications research.
Yuyao Lei +2 more
doaj +1 more source
Sub-Optimal Stabilizers of the Pendubot Using Various State Space Representations
Energies, 2022 This paper considers the issue of linear-quadratic regulator (LQR) design for nonlinear systems with the use of smooth state and input transformations.
Dariusz Pazderski +3 more
doaj +1 more source
Advances in Wishart-Type Modelling of Channel Capacity
Revstat Statistical Journal, 2020 This paper paves the way when the assumption of normality is challenged within the wireless communications systems arena. Innovative results pertaining to the distributions of quadratic forms and their associated eigenvalue density functions for the ...
J.T. Ferreira , A. Bekker , M. Arashi
doaj +1 more source
Regularity of Linear Systems of Differential Equations on the Axes and Pencils of Quadratic Forms
Communications in Advanced Mathematical Sciences, 2019 It is considered linear systems of differential equations and investigated questions of regularity of these systems. To explore the regularity it is comfortable to use quadratic form whose derivative with respect to the adjoint system is positive ...
Nataliya Stepanenko +2 more
doaj +1 more source