A5004128598- Gas Dynamics and Kinetic Theory
- Radiation Detection and Scintillator Technologies
- Advanced Numerical Methods in Computational Mathematics
- Numerical methods for differential equations
- Radiation Therapy and Dosimetry
- Meteorological Phenomena and Simulations
- Cardiac electrophysiology and arrhythmias
- Medical Imaging Techniques and Applications
- Computational Fluid Dynamics and Aerodynamics
- Advanced Radiotherapy Techniques
- Precipitation Measurement and Analysis
- Distributed and Parallel Computing Systems
- Semiconductor materials and devices
- Differential Equations and Numerical Methods
- Advanced Mathematical Modeling in Engineering
- Lattice Boltzmann Simulation Studies
- Plasma Diagnostics and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Parallel Computing and Optimization Techniques
- Matrix Theory and Algorithms
- Computational Physics and Python Applications
- Thermal properties of materials
- Nuclear Physics and Applications
- stochastic dynamics and bifurcation
- Pancreatic function and diabetes
University of Maryland, Baltimore County
2011-2023
University of Maryland, College Park
2002-2022
University of Maryland, Baltimore
1998-2021
University of Baltimore
1998
Arizona State University
1996-1998
University of Minnesota
1997
Motorola (United States)
1997
Electrochemical Society
1996
We studied the application of a deep, fully connected Neural Network (NN) to process prompt gamma (PG) data measured by Compton camera (CC) during delivery clinical proton radiotherapy beams. The network identifies 1) recorded “bad” PG events arising from background noise measurement, and 2) correct ordering interactions in CC help improve fidelity “good” used for image reconstruction. emission tissue-equivalent target irradiation with 150 MeV beam delivered at dose rates was prototype CC....
. Range uncertainty is a major concern affecting the delivery precision in proton therapy. The Compton camera (CC)-based prompt-gamma (PG) imaging promising technique to provide 3D
An integrated simulator for chemical vapor deposition is introduced. In addition to reactor scale and feature simulators, it includes a "mesoscopic" with the typical length of die. It shown that "three‐scale" used proper extension "two‐scale" simulators consist simulation models. Moreover, demonstrated information provided on new scale, which no available from approach, as well important corrections results scale. This enables, instance, studies microloading. Thermally induced silicon...
Proton beam radiotherapy is a method of cancer treatment that uses proton beams to irradiate cancerous tissue, while minimizing doses healthy tissue. In order guarantee the prescribed radiation dose delivered tumor and ensure tissue spared, many researchers have suggested verifying delivery through use real-time imaging using methods which can image prompt gamma rays are emitted along beam’s path patient such as Compton cameras (CC). However, because limitations CC, their images noisy...
We consider a model for chemical vapor deposition, the process of adsorption gas onto surface together with associated deposition reactant on surface. The has microscopic structure which, in context semiconductor manufacturing, arises from preprocessing wafer. Using singular perturbation analysis, boundary condition corresponding diffusion equation is derived, which allows replacement microstructured by flat boundary. asymptotic analysis numerically verified simple test example.
A model designed to deal with pattern dependences of deposition processes is discussed. It a mesoscopic scale in the sense that it deals spatial scales on order , which intermediate between reactor and feature scale. This accounts for effects microscopic surface structure via suitable averages obtained by homogenization technique from asymptotic analysis. Two studies low pressure chemical vapor silicon dioxide tetraethoxysilane are presented demonstrate model. The first study shows...
We present a transient Boltzmann equation based transport and reaction model for atomic layer deposition (ALD) at the feature scale. The has no adjustable parameters. In this article, we focus on step postreaction purge steps of ALD. heterogeneous chemistry consists reversible adsorption reactant single site, irreversible second gaseous with adsorbed reactant. conduct studies effect kinetic rate parameter associated reaction. provide results number densities species, fluxes to surface...
We present a Boltzmann equation-based model for transport and reaction in micrometer-scale features such as those found integrated circuit fabrication. focus on the adsorption desorption of one species to understand transient responses step changes at reactor scale. The has no adjustable parameters; assumptions are detailed. Adsorption reactions rates written simple reversible Langmuir rate expressions. Kinetic parameter values chosen demonstration. Results behavior number density, flux...
A model for the flow of calcium on scale one heart cell is given by a system time-dependent reaction-diffusion equations coupled nonlinear reaction terms. Calcium ions enter into at release units distributed throughout and then diffuse. At each unit, probability to be released increases along with concentration calcium, thus creating feedback loop waves regenerating themselves repeatedly. The validation this requires simulations time several repeated spatial entire cell. This long-time...
We present a parallel matrix‐free implicit finite volume scheme for the solution of unsteady three‐dimensional advection‐diffusion‐reaction equations with smooth and Dirac‐Delta source terms. The is formally second order in space Newton–Krylov method employed appearing nonlinear systems time integration. matrix‐vector product required hardcoded without any approximations, obtaining that needs little storage well‐suited implementation. describe implementation detail give numerical evidence...
Conventional radiation therapy of brain tumors often produces cognitive deficits, particularly in children. We investigated the potential efficacy merging Orthovoltage X-ray Minibeams (OXM). It segments beam into an array parallel, thin (~0.3 mm), planar beams, called minibeams, which are known from synchrotron x-ray experiments to spare tissues. Furthermore, slight divergence OXM make individual minibeams gradually broaden, thus with their neighbors at a given tissue depth produce solid...
Predicting violent storms and dangerous weather conditions with current models can take a long time due to the immense complexity associated simulation. Machine learning has potential classify tornadic patterns much more rapidly, thus allowing for timely alerts public. To deal class imbalance challenges in machine learning, different data augmentation approaches have been proposed. In this work, we examine wall difference between live methods versus use of preaugmented when they are used...