Dong Ahn, Dylan Chapp, Mario Guevara, Joy Kitson, Ricardo Llamas, Kento Sato, Michela Taufer, Rodrigo Vargas

With the Global Computing Lab, my research was primarily on the following two projects: (1) Applying machine learning methods to soil moisture data, to fill gaps and downscale resolution; (2) Modeling and analyzing nondeterminism in executions of parallel programs, especially involving MPI.

Zhanar Berikkyzy, Anton Bernshteyn, Beth Bjorkman, Axel Brandt, Garner Cochran, Joshua Cooper, Wei Gao, Sylvia Hobart, Sogol Jahanbekam, Bill Kay, Lauren Keough, Omid Khormali, Rachel Kirsch, Victor Larsen, Ryan Martin, Brent McKain, Kevin Moss, Mitch Phillipson, Jonathan Rollin, Songling Shan, Heather Smith, Claude Tardif, David Wehlau, Andrew Uzzell, Jennifer Wise, Imed Zaguia

My main mathematical interests lay in combinatorics on words, graph theory, discrete geometry, combinatorial limit theory, and applications of discrete mathematics to linguistics.

- Published Papers
- "A bound on a convexity measure for point sets."
*International Journal of Computational Geometry and Applications*(in press) [arXiv] - (with Bernshteyn, Khormali, Martin, Rollin, Shan, Uzzell) "Regular colorings of regular graphs."
*Discussiones Mathematicae Graph Theory***4**(3), April 2020. [Sciendo; DOI (DMGT); arXiv] - (with Llamas, Guevara, Taufer, Vargas) "Spatial Gap-Filling of ESA CCI Satellite-Derived Soil Moisture Based on Geostatistical Techniques and Multiple Regression."
*Remote Sensing***12**(4), February 2020 [DOI (MDPI); DOI (Preprints)] - (with Chapp, Sato, Ahn, Taufer) "A three-phase workflow for general and expressive representations of nondeterminism in HPC applications."
*International Journal of High Performance Computing Applications***33**(6)1175-1184, Nov 2019. [DOI (Sage)] - (with Guevara, Llamas, Kitson, Vargas, Taufer) "SOMOSPIE: A modular SOil MOisture SPatial Inference Engine based on data driven decisions."
*15th eScience*, September 2019. [DOI (IEEE); arXiv] - "Graph cover-saturation."
*Graphs and Combinatorics***35**(5)1225--1237, September 2019. [DOI; arXiv] - (with Bjorkman, Cochran, Gao, Keough, Kirsch, Philipson, Smith, Wise) "\(k\)-foldability of words."
*Discrete Applied Mathematics***259**:19--30, April 2019. [DOI (ScienceDirect); arXiv] - (with Tardif, Wehlau, Zaguia) "Iterated arc graphs."
*Commentationes Mathematicae Universitatis Carolinae***59**(3)277--283, 2018. [DOI (DML-CZ); CMUC; arXiv] - (with Cooper) "Density dichotomy in random words."
*Contributions to Discrete Mathematics***13**(1), January 2018. [DOI (UCalgary); arXiv] - (with Tardif, Wehlau) "Logical compactness and constraint satisfaction problems."
*Logical Methods in Computer Science***13**(1)#1:1--11, January 2017. [LMCS; arXiv] - (with Cooper) "Asymptotic Density of Zimin Words."
*Discrete Mathematics & Theoretical Computer Science***18**(3)#3, March 2016. [DMTCS; arXiv] - "Toward the Combinatorial Limit Theory of Free Words." University of South Carolina Dissertation, August 2015. [arXiv]
- (with Cooper) "Bounds on Zimin Word Avoidance."
*Congressus Numerantium***222**:87--95, 2014. [arXiv]

- "A bound on a convexity measure for point sets."
- Peer-Reviewed Abstracts and Posters
- (with Chapp, D. Brown, E. Deelman, K. Vahi, V. Welch, Taufer) "Applicability Study of the PRIMAD Model to LIGO Gravitational Wave Search Workflows." Position paper for P-RECS'19: 2nd International Workshop on Practical Reproducible Evaluation of Computer Systems.
- (with Chapp, Taufer) "Modeling Record-and-Replay for Nondeterministic Applications on Exascale Systems." Position paper for ModSim 2018.
- (with Llamas, Guevara, Taufer, Vargas) "Large-Scale Soil Moisture Modeling Based on Linear Geostatistics and Remotely Sensed Data." Poster at the AGU 2018 Fall Meeting.

- Papers Under Revision
- (with Berikkyzy, Brandt, Jahanbekam, Larsen) "Antimagic Labelings of Weighted Graphs." [arXiv]

- In Preparation
- (with Berikkyzy, Bjorkman, Hobart, Jahanbekam, Kay, Keough, McKain, Moss, Shan, Smith) "Triangle-distinct graphs."

- Other

- "Cyberinstractures for Scientific Discovery with Emphasis on Wildfire Simulations" (40 min). Fire Research Division seminar, National Institute of Standards and Technology (NIST), Gaithersburg. 20 March 2019.
- "A Workflow for Soil Moisture Analytics" (20 min). Innovative Computing Laboratory seminar, University of Tennessee at Knoxville. 15 March 2019.
- "Integer Sequences" (50 min). Mathematics and Statistics Colloquium, Colby College. 11 October 2018. [seminar schedule]
- "Graph domination-saturation" (50 min). Combinatorics, Algebra, and Topology Seminar, United States Naval Academy. 23 April 2018. [seminar schedule]
- "Combinatorial Nullstellensatz in Graph Theory" (20 min), Special Session on Advanced Techniques in Graph Theory. AMS Sectional Meeting, University of Buffalo. 17 September 2017. [program listing]
- "Bridging Logic and Constraint Satisfaction with Relational Structures and Filters" (60 min). Logic and Combinatorics Seminars (combined), McGill University. 4 November 2016.
- "Antimagic Graphs and Combinatorial Nullstellensatz" (60 min). Graduate Seminar, University of Colorado Denver. 29 September 2014.
- "Collatz Generalized: An Expansion of the \(3x + 1\) Problem" (25 min).
*11th Carolina Math Seminar*, Benedict College. 2 February 2012. [video]

- É. Czabarka, M. Marsili, L. Székely. "Threshold functions for distinct parts: revisiting Erdős-Lehner." [arXiv]

- A. Carayol, S. Göller, "On Long Words Avoiding Zimin Patterns."
*Theory of Computing Systems*, March 2019, special issue on Theoretical Aspects of Computer Science (STACS 2017)**19**:1–13 [DOI (TCS); DOI (STACS); arXiv]; - D. Conlon, J. Fox, B. Sudakov. "Tower-type bounds for unavoidable patterns in words."
*Transactions of the American Mathematical Society*,**372**:6213–6229, May 2019 [DOI; arXiv] - J. Connor. "A Self-Referential Property of Zimin Words." [arXiv]
- I. De Feis, "Optimal Interpolation for Infrared Products from Hyperspectral Satellite Imagers and Sounders."
*Sensors***20**(8), April 2020. [DOI] - E. Drellich and H. C. Smith, "Folding Words Around Trees: Models Inspired by RNA."
*A Project-Based Guide to Undergraduate Research in Mathematics*, chapter 1, April 2020. [DOI] - A.Lozano, M. Mora, C. Seara. "Antimagic Labelings of Caterpillars."
*Applied Mathematics and Computation*,**347**:734–740, April 2019 [DOI] - N. Mhaskar, M. Soltys. "Forced Repetitions over Alphabet Lists." [pdf]
- W. Rytter, A. Shur. "Searching for Zimin patterns."
*Theoretical Computer Science***571**:50–57, March 2015. [ACM DL] - S. Thomas. "Talk and Tradition: Connections between Language and Culture in Igboland." [Academia]

- Argonne Training Program on Extreme-Scale Computing (ATPESC)

August 2018, Q Center, St. Charles, Illinois - São Paulo School of Advanced Science on Algorithms, Combinatorics and Optimization (SPSAS-ACO)

July 2016, Instituto de Matemática e Estatística, Universidade de São Paulo - LMS-CMI Research School, Regularity and Analytic Methods in Combinatorics (RAMC)

July 2015, University of Warwick, Coventry - Rocky Mountain-Great Plains Graduate Research Workshop in Combinatorics (GRWC 2015)

June 2015, Iowa State University, Ames - Rocky Mountain-Great Plains Graduate Research Workshop in Combinatorics (GRWC 2014)

August 2014, University of Colorado Denver & University of Denver - Graph Limits, Groups and Stochastic Processes summer school and workshop

June 2014, MTA Rényi Institute of Mathematics, Budapest - NSF Research Experience for Undergraduates, UA VIGRE, Arizona Summer Program in Computational Photonics

July 2009, University of Arizona, Tucson