A5102982237- Solidification and crystal growth phenomena
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Rheology and Fluid Dynamics Studies
- Astronomy and Astrophysical Research
- Fluid Dynamics and Turbulent Flows
- Fluid Dynamics and Thin Films
- Ocean Waves and Remote Sensing
- Silicon and Solar Cell Technologies
- Fluid Dynamics and Vibration Analysis
- Meteorological Phenomena and Simulations
- Oceanographic and Atmospheric Processes
- Tropical and Extratropical Cyclones Research
- Planetary Science and Exploration
- Metallurgical Processes and Thermodynamics
- Adaptive optics and wavefront sensing
- Aluminum Alloy Microstructure Properties
- Galaxies: Formation, Evolution, Phenomena
- Fluid Dynamics and Heat Transfer
- Coastal and Marine Dynamics
- Astrophysics and Star Formation Studies
- Material Dynamics and Properties
- Gamma-ray bursts and supernovae
- nanoparticles nucleation surface interactions
- Thin-Film Transistor Technologies
Memorial University of Newfoundland
2022-2023
Space Telescope Science Institute
2007-2017
University of Illinois Urbana-Champaign
2016
University of Colorado Boulder
2015
University College London
2012
Foothills Medical Centre
2005-2011
University of Washington
1998-2010
University of Calgary
2003-2009
Boston University
2007-2009
Massachusetts Institute of Technology
1996-2006
A constitutive equation for computing particle concentration and velocity fields in concentrated monomodal suspensions is proposed that consists of two parts: a Newtonian which the viscosity depends on local volume fraction diffusion accounts shear-induced migration. Particle flux expressions used to obtain are derived by simple scaling arguments. Predictions made steady Couette Poiseuille flow, transient start-up shear flow apparatus. concentrations suspension polymethyl methacrylate...
A solid sphere falling through a Bingham plastic moves in small envelope of fluid with shape that depends on the yield stress. finite-element/Newton method is presented for solving free-boundary problem composed velocity and pressure fields surfaces creeping flow. Besides outer surface, occurs as caps at front back because stagnation points The accuracy solutions ascertained by mesh refinement calculation integrals corresponding to maximum minimum variational principles problem. Large...
We measure the morphology--density relation (MDR) and morphology-radius (MRR) for galaxies in seven z ~ 1 clusters that have been observed with Advanced Camera Surveys on board Hubble Space Telescope. Simulations independent comparisons of ourvisually derived morphologies indicate ACS allows one to distinguish between E, S0, spiral down zmag = 24, corresponding L/L* 0.21 0.30 at 0.83 1.24, respectively. adopt density radius estimation methods match those used lower redshift order study...
Abstract The quality of large semiconductor crystals grown from the melt for use in electronic and optoelectronic devices is strongly influenced by intricate coupling heat mass transfer flow growth systems. This paper reviews present state understanding these processes starting simplest descriptions solidification to detailed numerical calculations needed quantitative modeling processing with solidification. Descriptions models vertical Bridgman‐Stockbarger Czochralski crystal techniques are...
We analyze deep multicolor Advanced Camera images of the largest known gravitational lens, A1689. Radial and tangential arcs delineate critical curves in unprecedented detail, many small counterimages are found near center mass. construct a flexible light deflection field to predict appearance positions counterimages. The model is refined as new identified incorporated improve model, yielding total 106 30 multiply lensed background galaxies, spanning wide redshift range, 1.0 < z 5.5....
Moderate-amplitude axisymmetric oscillations of incompressible inviscid drops and bubbles are studied using a Poincaré–Lindstedt expansion technique. The corrections to the drop shape velocity potential caused by mode coupling at second order in amplitude predicted for two-, three- four-lobed motions. frequency oscillation is found decrease with square amplitude; this result compares well experiments numerical calculations undergoing two-lobed oscillations.
We present the analysis of faint galaxy population in Advanced Camera for Surveys (ACS) Early Release Observation fields VV 29 (UGC 10214) and NGC 4676.These observations cover a total area 26.3 arcmin 2 , have depths close to that Hubble Deep Fields deepest part image, with 10σ detection limits point sources 27.8, 27.6 27.2 AB magnitudes g F 475W V 606W I 814W bands respectively.Measuring number count distribution is difficult task, different groups arriving at widely varying results even...
We present F435W (B), F606W (broad V), and F814W I) coronagraphic images of the debris disk around β Pictoris obtained with Hubble Space Telescope's Advanced Camera for Surveys. These provide most photometrically accurate morphologically detailed views between 30 300 AU from star ever recorded in scattered light. confirm that previously reported warp inner is a distinct secondary inclined by ∼5° main disk. The projected spine coincides isophotal inflections, or "butterfly asymmetry," seen at...
On the SEASAT‐A satellite, a microwave scatterometer was used to determine vector wind over world's oceans. The technique is based on sensitivity of radar backscatter centimeter length ocean waves created by action surface wind. This paper describes algorithm convert scatterometer's measurements normalized cross section, σ°, neutral stability at 19.5 m height and comparison these winds with high quality observations. an empirical σ° model function describe dependence σ 0 19.5‐m vector. Two...
The steady-state and time-dependent flow transitions observed in a well-characterized viscoelastic fluid flowing through an abrupt axisymmetric contraction are characterized terms of the Deborah number ratio by laser-Doppler velocimetry visualization measurements. A sequence identified that lead to time-periodic, quasi-periodic aperiodic dynamics near lip formation elastic vortex at entrance. This increases intensity expands outwards into upstream tube as is increased, until further...
The equations of motion for a neutrally buoyant fluid are solved to produce an equilibrium flow consisting modified Ekman spiral mean plus helical secondary flow. By considering the be finite perturbation on large-scale flow, approximate obtained and functions parameters. When energetics this system considered, magnitude can obtained. perturbations assumed preserve structure infinitesimal solutions dynamic instability boundary layer. In particular, rolls occur as solutions. These...
Equilibrium shapes and stability of rotating drops held together by surface tension are found computer-aided analysis that uses expansions in finiteelement basis functions. Shapes calculated as extrema appropriate energies. Stability relative determined from curvatures the energy neighbourhood extremum. Families axisymmetric, two-, three- four-lobed drop traced systematically. Bifurcation turning points located principle exchange stabilities is tested. The axisymmetric stable at low rotation...
Examining the frequency content of signals is critical in many applications, from neuroscience to astronomy. Many techniques have been proposed accomplish this. One these, S-transform, provides simultaneous time and information similar wavelet transform, but uses sinusoidal basis functions produce globally referenced phase measurements. It has shown promise medical imaging applications high computational requirements. This paper presents a general transform that describes Fourier-family...
Multicolor coronagraphic images of the circumstellar disk around HD141569A have been obtained with Hubble Space Telescope (HST) Advanced Camera for Surveys. B, V, and I show that disk's previously-described multiple-ring structure is actually a continuous distribution dust tightly-wound spiral structure. Two, more open arms extend from disk, one which appears to reach nearby binary star HD141569BC. Diffuse seen up 1200AU HD141569A. Although planets may exist in inner region tidal interaction...
Laser Doppler velocimetry (LDV) and video flow visualization are used to investigate the creeping motion of a highly elastic, constant-viscosity fluid flowing past cylinder mounted centrally in rectangular channel. A sequence viscoelastic transitions documented as volumetric rate is increased elastic effects become increasingly important. Velocity profiles clearly show that elasticity has almost no effect on kinematics upstream cylinder, but streamlines wake gradually shifted further...
The deployment of a space-based Doppler lidar would provide information that is fundamental to advancing the understanding and prediction weather climate. This paper reviews concepts wind measurement by lidar, highlights results some observing system simulation experiments with winds, discusses important advances in earth science anticipated winds. Observing experiments, conducted using two different general circulation models, have shown 1) there significant improvement forecast accuracy...