TARU PUBLICATIONS
Journal of Interdisciplinary Mathematics cover
Hybrid ·Peer-reviewed·ISSN (Online): 2169-012X·ISSN (Print): 0972-0502

Monthly Journal: Publishes the methodological and theoretical role of mathematics and mathematical applications underpinning scientific research.

Issues up to 2022 co-published with and available at:Taylor & Francis Online
submissions@tarupublications.com
Open Access Research Article

On Foster’s theorem and positive para odd functions

*

* Corresponding author · click or hover a name for details

pp. 67–75Vol. 27Issue 1February 2024DOI: 10.47974/JIM-1725XML
Received:
05 Jan 2023
Published Online:
27 Feb 2024
Article type:
Research Article
Language:
EN
Article no.:
JIM-1725
Pages:
67–75

Abstract

Various tools in the literature are used to enhance the understanding of the Routh-Hurwitz stability theory. Among such tools are Foster’s theorem and positive para odd functions. One of the objectives of this paper is to show strong correlations between these two tools. Such correlations enable us to create simple forms of such functions which can prove useful in tackling stability issues. Also, a simple derivation of Foster’s Theorem is advanced using complex analysis techniques, avoiding the use of circuit network theory which led to Foster’s theorem. A general form of positive and para odd functions is also advanced.

Keywords

Subject Classifications

(2010) Primary 37C7593C15. Secondary 93D30E

References

[1] Rhodes, D. R. “A reactance theorem,” Proc. Roy. Soc. London, vol. 353,  pp. 1–10 (1977).
[2] Zahreddine, Z. New Versions of the Hermite Bieler Theorem in Stability Contexts, American Journal of Applied Mathematics, Volume 7, Issue 1, Pages: 1-4 (February 2019).
[3] Zahreddine, Z. On Positive Para-odd and Complex Discrete Reactance Functions, Journal of Interdisciplinary Mathematics, Taylor & Francis, Vol. 21, Issue 1, 243-251, https://doi.org/10.1080/09720502.2017.1367525
[4] Horn, R.; Johnson, C. Topics in Matrix Analysis; Cambridge University Press: Cambridge, UK (1991).
[5] Barnett, S. Some Modern Applications of Mathematics, Ellis Horwood, London (1995).
[6] Zahreddine, Z. Symmetric Properties of Routh–Hurwitz and Schur–Cohn Stability Criteria, Symmetry 2022, 14(3), 603. https://doi.org/10.3390/sym14030603.
[7] Zahreddine, Z. Structural Properties of Some Classes of Functions Arising in Stability Theory. Journal of Interdisciplinary Mathematics, Volume 24, Number 8, P: 2313-2321 (December 2021), https://doi.org/10.1080/09720502.2021.1914367.
[8] Zahreddine, Z. Continued Fraction Expansions of Stable Discrete-Time Systems of Difference Equations, Symmetry 2022, 14, 1226. https://doi.org/10.3390/sym14061226.
[9] Adler, R.B,; Chu, L.J.; Fano, R.M. Electromagnetic Energy Transmission and Radiation. New York: Wiley (1965).
[10] Talbot, A. Some Theorems on Positive Functions. IEEE Transactions on Circuit Theory, Vol. CT-12, No. 4, pp. 607-608 (December, 1965).
[11] Zahreddine, Z. An Extension of the Routh Array for the Asymptotic Stability of a System of Differential Equations with Complex Coefficients, Applicable Analysis, Vol. 49, 61-72 (1993).

Views: 187Downloads: 76Citations: 0