2026 Oscar H. Ibarra: Computer Science Researcher – H-Index, Publications & Awards

Discipline name	D-Index	World Ranking	Current World Ranking	National Ranking	Current National Ranking	Publications	Citations
Computer Science	54	4565	4436	2134	2059	400	11675

Research.com Recognitions

2008 - Member of Academia Europaea
1995 - ACM Fellow For contributions to the design and analysis of algorithms, the theory of computation, computational complexity, and parallel computing.
1993 - Fellow of the American Association for the Advancement of Science (AAAS)
1984 - Fellow of John Simon Guggenheim Memorial Foundation

Overview

Óscar H. Ibarra is affiliated with the University of California, Santa Barbara in the United States. Their research spans multiple areas within computer science and biochemistry, genetics, and molecular biology, focusing particularly on computational theory, formal languages, and automata theory.

The main fields of study for Óscar H. Ibarra include:

Computer Science
Biochemistry, Genetics and Molecular Biology

Within these areas, the scientist's work is concentrated in several subfields:

Computational Theory and Mathematics
Artificial Intelligence
Molecular Biology
Industrial and Manufacturing Engineering
Control and Systems Engineering

The core topics of research covered by Óscar H. Ibarra comprise:

semigroups and automata theory
DNA and Biological Computing
Logic, programming, and type systems
Algorithms and Data Compression
Machine Learning and Algorithms
Computability, Logic, AI Algorithms
Cellular Automata and Applications

Óscar H. Ibarra has published extensively, frequently appearing in the following venues:

International Journal of Foundations of Computer Science
Information and Computation
Theoretical Computer Science
SSRN Electronic Journal
arXiv (Cornell University)

Recent papers authored by Óscar H. Ibarra include:

Semilinearity of Families of Languages, 2020, International Journal of Foundations of Computer Science
Generalizations of Checking Stack Automata: Characterizations and Hierarchies, 2021, International Journal of Foundations of Computer Science
Space Complexity of Stack Automata Models, 2021, International Journal of Foundations of Computer Science
On the complexity of decision problems for some classes of machines and applications, 2023, Information and Computation

Other papers connected to their network of research include:

Relationships between bounded languages, counter machines, finite-index grammars, ambiguity, and commutative regularity, 2020, Theoretical Computer Science

The researcher has frequently collaborated with the following co-authors:

Ian McQuillan
Flavio D'Alessandro
Pascal Baumann
Moses Ganardi
Lia Schütze

Óscar H. Ibarra has received several awards during their career, including:

Member of Academia Europaea (2008)
ACM Fellow (1995) for contributions to the design and analysis of algorithms, the theory of computation, computational complexity, and parallel computing
Fellow of the American Association for the Advancement of Science (AAAS) (1993)
Fellow of John Simon Guggenheim Memorial Foundation (1984)

Best Publications

Fast Approximation Algorithms for the Knapsack and Sum of Subset Problems

Oscar H. Ibarra;Chul E. Kim

1386
Citations
Heuristic Algorithms for Scheduling Independent Tasks on Nonidentical Processors

Oscar H. Ibarra;Chul E. Kim

1167
Citations
Reversal-Bounded Multicounter Machines and Their Decision Problems

Oscar H. Ibarra

643
Citations
Polynomially Complete Fault Detection Problems

O.H. Ibarra;S.K. Sahni

379
Citations
Bounds for LPT Schedules on Uniform Processors

Teofilo F. Gonzalez;Oscar H. Ibarra;Sartaj Sahni

267
Citations
SWEB: towards a scalable World Wide Web server on multicomputers

D. Andresen;Tao Yang;V. Holmedahl;O.H. Ibarra

244
Citations
Asynchronous spiking neural P systems

Matteo Cavaliere;Oscar H. Ibarra;Gheorghe Pun;Omer Egecioglu

191
Citations
A generalization of the fast LUP matrix decomposition algorithm and applications

Oscar H Ibarra;Shlomo Moran;Roger Hui

184
Citations
The complexity of decision problems for finite-turn multicounter machines

Eitan M. Gurari;Oscar H. Ibarra

174
Citations
Automated composition of e-services: lookaheads

Çagdaş Evren Gerede;Richard Hull;Oscar H. Ibarra;Jianwen Su

142
Citations
Simple matrix languages

Oscar H. Ibarra

137
Citations
Normal forms for spiking neural P systems

Oscar H. Ibarra;Andrei Pun;Gheorghe Pun;Alfonso Rodríguez-Patón

135
Citations
On two-way multihead automata

Oscar H. Ibarra

133
Citations
Probabilistic Algorithms for Deciding Equivalence of Straight-Line Programs

Oscar H. Ibarra;Shlomo Moran

132
Citations
A note on finite-valued and finitely ambiguous transducers

Eitan M. Gurari;Oscar H. Ibarra

122
Citations
Characterizations and computational complexity of systolic trellis automata

Oscar H. Ibarra;Sam M. Kim

109
Citations
Symbolic String Verification: An Automata-Based Approach

Fang Yu;Tevfik Bultan;Marco Cova;Oscar H. Ibarra

109
Citations
Relating the type of ambiguity of finite automata to the succinctness of their representation

B. Ravikumar;O. H. Ibarra

108
Citations
Sequential SNP systems based on min/max spike number

Oscar H. Ibarra;Andrei Pun;Alfonso Rodríguez-Patón

102
Citations
Characterizations of some tape and time complexity classes of turing machines in terms of multihead and auxiliary stack automata

Oscar H. Ibarra

101
Citations
Multi-tape and multi-head pushdown automata

Michael A. Harrison;Oscar H. Ibarra

100
Citations

Frequent Co-Authors

Jianwen Su University of California, Santa Barbara

Tao Jiang University of California, Riverside

Tevfik Bultan University of California, Santa Barbara

Shlomo Moran Technion – Israel Institute of Technology

Richard A. Kemmerer University of California, Santa Barbara

Lila Kari University of Waterloo

Koji Nakano Hiroshima University

Sartaj Sahni University of Florida

Terence R. Smith University of California, Santa Barbara

Arto Salomaa Turku Centre for Computer Science

External Links

Wikipedia of Oscar H. Ibarra Personal website of Oscar H. Ibarra

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