![[picture of
J.T. Quah]](images/jq-akbar.jpg)
![[cartoon diagram of a stepped crystal surface]](images/step-cartoon-labeled.png "cartoon diagram of a stepped crystal surface")
Introduction
I graduated from Bates College with a B.S. in mathematics and then came to the University of Maryland for graduate work in the Applied Mathematics and Scientific Computation program. There the extensive interdisciplinary collaborations exposed me to interesting problems at the interface of mathematics and physics. I studied smooth dynamical systems and data assimilation methods in the context of numerical weather prediction. More recently I have focused on problems in surface physics, specifically the PDEs describing epitaxial phenomena in crystals, and numerical schemes for solving them efficiently.
I defended my dissertation, A Macroscale Perspective of Near-Equilibrium Relaxation of Stepped Crystal Surfaces, in June 2009. With Dio and other collaborators at Maryland, I continue to work on problems inspired by this research.
Research
My CV in PDF format
Current activities
- Understanding the macroscale consequences in crystal materials of surface physics phenomena at the nanoscale (with advisor D. Margetis)
- Solving nonlinear boundary value problems numerically, with the goal of comparing against lab results and analytical predictions (with D. Margetis, R. Nochetto, and A. Bonito)
Papers
- J. Quah and D. Margetis, ``Electromigration in Macroscopic Relaxation of Stepped Surfaces'', accepted for publication in SIAM Multiscale Modeling and Simulation.
- A. Bonito, R. Nochetto, J. Quah, and D. Margetis, ``Self-organization of decaying surface corrugations: A numerical study'', Physical Review E, Vol. 79, 050601(R).
- J. Quah, J. Young, and D. Margetis, ``A macroscopic view of crystal step transparency'', Physical Review E, Vol. 78, 042602, pp. 1--4.
- J. Quah and D. Margetis, ``Anisotropic diffusion in continuum relaxation of stepped crystal surfaces'', Journal of Physics A: Mathematical and Theoretical, Vol. 41, 235004, pp. 1--18.
Less recent work
- Improving regional weather forecasts with data assimilation methods (with E. Kalnay and other collaborators at ESSIC)
- Computing special Jordan pencils that arise in the study of composite materials (with E. Blew, Y. Grabovsky, M. Jacobs, and M. Macauley)
Teaching
To learn, read.
To know, write.
To master, teach.
Current courses
Previous courses
- MATH 140 (Calculus 1), Fall Semester 2008
- MATH 141 (Calculus 2), Spring Semester 2008
- MATH 246 (Differential Equations for Scientists and Engineers), Fall Semester 2007
- MATH 220 (Calculus 1), Fall Semester 2005
![[math club problem]](images/circ-triangle.png "[math club problem]")
Given AC = 3\sqrt{2}, AB = 15\sqrt{2}, and BC = 24, determine OB, the
radius of the circumscribed circle.