- Home
- Top Scientists - Mathematics
- Donal O'Regan

Discipline name
H-index
Citations
Publications
World Ranking
National Ranking

Mathematics
H-index
74
Citations
24,822
1,055
World Ranking
89
National Ranking
1

2011 - Member of the Royal Irish Academy

- Mathematical analysis
- Quantum mechanics
- Differential equation

The scientist’s investigation covers issues in Mathematical analysis, Boundary value problem, Differential equation, Nonlinear system and Pure mathematics. His Mathematical analysis study focuses mostly on Singular solution, Fixed-point theorem, Order, Numerical partial differential equations and C0-semigroup. His studies deal with areas such as Eigenvalues and eigenvectors and Applied mathematics as well as Boundary value problem.

His Differential equation study incorporates themes from Initial value problem, Variable and Existence theorem. His work deals with themes such as Dynamical systems theory, Integral equation and Monotone polygon, which intersect with Nonlinear system. His biological study spans a wide range of topics, including Volterra integral equation, Type and Constant.

- Positive Solutions of Differential, Difference and Integral Equations (554 citations)
- Dynamic equations on time scales: a survey (481 citations)
- Generalized contractions in partially ordered metric spaces (453 citations)

Donal O'Regan focuses on Mathematical analysis, Pure mathematics, Boundary value problem, Nonlinear system and Fixed-point theorem. His is doing research in Differential equation, Singular solution, Order, Integral equation and Banach space, both of which are found in Mathematical analysis. His Pure mathematics research integrates issues from Class and Type.

His Boundary value problem research includes elements of Combinatorics and Ordinary differential equation. His Nonlinear system research incorporates elements of Sign and Applied mathematics. His Fixed-point theorem research is included under the broader classification of Discrete mathematics.

- Mathematical analysis (53.18%)
- Pure mathematics (23.41%)
- Boundary value problem (22.17%)

- Applied mathematics (16.57%)
- Mathematical analysis (53.18%)
- Pure mathematics (23.41%)

His main research concerns Applied mathematics, Mathematical analysis, Pure mathematics, Nonlinear system and Differential equation. Donal O'Regan interconnects Initial value problem, Lyapunov function and Stability in the investigation of issues within Applied mathematics. His Mathematical analysis study frequently draws connections between adjacent fields such as Dynamic equation.

His Pure mathematics study combines topics in areas such as Class and Type. His research is interdisciplinary, bridging the disciplines of Inequality and Type. His study in Nonlinear system is interdisciplinary in nature, drawing from both Order, Function and Uniqueness.

- Stability by Lyapunov like functions of nonlinear differential equations with non-instantaneous impulses (36 citations)
- A note on initial value problems for fractional fuzzy differential equations (34 citations)
- Solving interval-valued fractional initial value problems under Caputo gH-fractional differentiability (32 citations)

- Mathematical analysis
- Quantum mechanics
- Algebra

His primary areas of investigation include Applied mathematics, Nonlinear system, Mathematical analysis, Fractional differential and Differential equation. His work carried out in the field of Applied mathematics brings together such families of science as Initial value problem, Partial differential equation, Uniqueness and Stability. His work deals with themes such as Discrete mathematics, Controllability, Boundary value problem, Function and Order, which intersect with Nonlinear system.

Space, p-Laplacian, Operator, Linear differential equation and C0-semigroup are among the areas of Mathematical analysis where Donal O'Regan concentrates his study. His Fractional differential research also works with subjects such as

- Lyapunov function that connect with fields like Stability theory,
- Riemann liouville which is related to area like Degree. The concepts of his Differential equation study are interwoven with issues in Pure mathematics, Action and Integer.

This overview was generated by a machine learning system which analysed the scientist’s body of work. If you have any feedback, you can contact us here.

Positive Solutions of Differential, Difference and Integral Equations

Ravi P. Agarwal;Donal O'Regan;Patricia J. Y Wong.

**(1998)**

935 Citations

Dynamic equations on time scales: a survey

Ravi Agarwal;Martin Bohner;Donal O'Regan;Allan Peterson.

Journal of Computational and Applied Mathematics **(2002)**

717 Citations

Generalized contractions in partially ordered metric spaces

R P Agarwal;El Gebeily;D Oregan.

Applicable Analysis **(2008)**

686 Citations

Oscillation Theory for Difference and Functional Differential Equations

Ravi P. Agarwal;Said R Grace;Donal O'Regan.

**(2000)**

600 Citations

Fixed Point Theory for Lipschitzian-type Mappings with Applications

D. R. Sahu;Donal O'Regan;Ravi P. Agarwal.

**(2009)**

511 Citations

Infinite Interval Problems for Differential, Difference and Integral Equations

Ravi P. Agarwal;Donal O'Regan.

**(2001)**

471 Citations

Variational approach to impulsive differential equations

Juan J. Nieto;Donal O’Regan.

Nonlinear Analysis-real World Applications **(2009)**

457 Citations

Fixed point theorems for generalized contractions in ordered metric spaces

Donal O'Regan;Adrian Petruşel.

Journal of Mathematical Analysis and Applications **(2008)**

422 Citations

Theory of singular boundary value problems

Donal O'Regan.

**(1994)**

408 Citations

Discrete Oscillation Theory

Ravi P. Agarwal;Martin. Bohner;Said R Grace;Donal O'Regan.

**(2005)**

339 Citations

Profile was last updated on December 6th, 2021.

Research.com Ranking is based on data retrieved from the Microsoft Academic Graph (MAG).

The ranking h-index is inferred from publications deemed to belong to the considered discipline.

If you think any of the details on this page are incorrect, let us know.

Contact us

Texas A&M University – Kingsville

King Abdulaziz University

Guizhou University

Mansoura University

Çankaya University

Florida Institute of Technology

National Technical University of Athens

Nanjing University

King Abdulaziz University

Bharathiar University

We appreciate your kind effort to assist us to improve this page, it would be helpful providing us with as much detail as possible in the text box below:

Something went wrong. Please try again later.