A5046902229- Visual perception and processing mechanisms
- Neural dynamics and brain function
- Color perception and design
- Impact of Light on Environment and Health
- Particle Accelerators and Free-Electron Lasers
- Advanced X-ray Imaging Techniques
- Color Science and Applications
- Motor Control and Adaptation
- Advanced Vision and Imaging
- Spatial Cognition and Navigation
- Pulsed Power Technology Applications
- Silicon Carbide Semiconductor Technologies
- Tactile and Sensory Interactions
- Neurobiology and Insect Physiology Research
- Particle accelerators and beam dynamics
- Urban Green Space and Health
- Diamond and Carbon-based Materials Research
- Multisensory perception and integration
- Radio Wave Propagation Studies
- Visual and Cognitive Learning Processes
- Sport Psychology and Performance
- Advanced Optical Imaging Technologies
- Visual Attention and Saliency Detection
- Superconducting Materials and Applications
- Ophthalmology and Visual Impairment Studies
National University of Tucumán
2010-2024
Consejo Nacional de Investigaciones Científicas y Técnicas
2005-2024
Los Alamos National Laboratory
2005-2024
Centro Científico Tecnológico - Tucumán
2010-2019
Bühler (United Kingdom)
2018
New Mexico State University
2015-2016
Instituto de la Visión
2015
University of Southern California
2002-2010
Centro Científico Tecnológico - San Juan
2006-2009
Los Alamos National Security (United States)
2006-2007
Humans are capable of picking up the invariance an object's physical speed regardless distance from which it is seen. This ability known as constancy. Typically studies constancy focus on spatiotemporal cues present in stimulus. In this work we a series experiments that introduce familiarity combination with other to study The results first experiment show human observers use said estimation objects. When added stimulus, helps system achieve second remove contextual and effect Finally,...
Abstract We present a series of experiments exploring the effect chromaticity on reaction time (RT) for variety stimulus conditions, including chromatic and luminance contrast, luminance, size. The these stimuli was varied along vectors in color space that included two chromatic-opponent-cone axes, red–green (L–M) axis blue–yellow [S − (L + M)] axis, intermediate noncardinal orientations, as well M). For Weber contrasts above 10–20%, RTs tend to same asymptote, irrespective direction. At...
We report an experiment that examines the performance of rugby union players and a control group composed graduate student with no sport experience, in multiple-object tracking task. It compares ability 86 high level grouped as Backs Forwards group, to track subset randomly moving targets amongst same number distractors. Several difficulties were included experimental design order evaluate possible interactions between relevant variables. Results show is better than other groups, but...
We systematized the study of effect glare on reaction time (RT), for visual conditions similar to ones found during night driving: Mesopic range adaptation (0.14 cd/m2), levels order those produced by car headlights (EG=15, 60 lx), suprathreshold luminance contrasts, and a variety spatial frequencies covering selected visibility (1, 2, 4, 8 c/deg). that no-glare situation, RT increases with decreasing contrast increasing frequency, which agrees previous findings. When data are plotted as...
The DARHT facility will employ two perpendicular electron Linear Induction Accelerators to produce intense, bremsstrahlung x-ray pulses for flash radiography. second axis, II [1], features an 18 MeV, 2-kA, 2-microsecond pulse accelerator. accelerator cells have undergone a series of testing and modeling efforts fully understand their unacceptable initial failure rate. These R&D are part the 2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...
This paper reports a study of the effect disability glare in scotopic-mesopic range when there is brief exposure to provide conditions similar those encountered night driving. Subjects compare brightness two uniform luminance fields that are displayed sequentially, one them presented under conditions. The observers report which field brighter. A forced-choice paradigm using method constant stimuli used determine corresponding perceptual matching luminance. Results show non-linear relation...
The Dual-Axis Radiographic Hydrodynamics Test (DARHT) facility will employ two perpendicular electron Linear Induction Accelerators to produce intense, bremsstrahlung x-ray pulses for flash radiography. second axis, DARHT II [1], features a 3-MeV, 2-kA injector and 15-MeV, 1.6-microsecond accelerator consisting of 74 induction cells drivers. Major cell components include high flux swing magnetic material (Metglas 2605SC) Mycalex™ insulator. drivers are pulse forming networks (PFNs). have...
It was shown that a peripheral glare source reduces the brightness of foveal stimulus. We hypothesized this reduction is governed by an inhibitory effect on test. reported results investigation dynamic incremental stimulus immediately after onset in field view. A magnitude comparison paradigm using constant stimuli adopted to determine luminance appeared equal standard patch. The mesopic range (0.5 cd/m2), and levels were 15 60 lx. Results showed time course followed typical shape attributed...
A low-cost system consisting of a commercial DSLR camera and long focal length zoom lens is introduced for the purpose recording guiding bending phenomena caused by atmospheric refraction in planetary boundary layer. significant advantage this that duration monitoring (weeks or months) possible with operated time-lapse mode. Recent experiments were performed type over 12.8 km path Dayton, OH 15.3 Las Cruces, NM. The measured downward vertical drift target images daytime (10 to 50 pixels) are...
In this work we consider atmospheric refractive bending and its effects on long-range imaging along a horizontal path. Refraction can impact the ability of remote sensing or image system to accurately locate objects determine their apparent proportions. We use low-cost commercial camera operating in time-lapse mode for refraction studies have been recording images building that is 15.3 km west camera. Based paraxial ray equation, solution height angle obtained index profile with curvature. A...
Retinal images evolve continuously over time owing to self-motions and movements in the world. Such an evolving image, also known as optic flow, if arising from natural scenes can be locally decomposed a Bayesian manner into several elementary components, including translation, expansion, rotation. To take advantage of this decomposition, brain has neurons tuned these types motions. However, typically have large receptive fields, often spanning tens degrees visual angle. Can such compute...
Recent performance and reliability upgrades to the dual axis radiographic hydrodynamic test (DARHT) facility second induction cells have impacted various cell mechanical components. To attain a higher level of reliability, key elements comprising were redesigned. These include oil-vacuum insulator assembly, cathode cap, oil vacuum region extension hardware, cores' insulating material configuration, high voltage drive plate. While developing these upgrades, other enhancements, unrelated...
When a bright light is present in the field of view, visibility dramatically reduced. Many studies have investigated effect glare on considering foveal vision. However, effects peripheral vision received little attention. In previous work [J. Opt. Soc. Am. A 25, 1790 (2008)], we showed that reaction time (RT) for at mesopic adaptation depends stimulus spatial frequency. this work, extend study to We measured RT achromatic sinusoidal gratings as function contrast range frequency, and...
The DARHT-II accelerator [1] will produce a 2-kA, 17-MeV beam in 1600-ns pulse when completed this summer. After exiting the accelerator, is sliced into four short pulses by kicker and quadrupole septum then transported for several meters to tantalum target conversion x-rays radiography. We describe tests of kicker, septum, transport, multipulse converter using assembled from first available refurbished cells. This scaled was operated at ~8 MeV ~1 kA, providing with approximately same ?/? as...
The Dual Axis Radiographic Hydrodynamic Test Facility (DARHT) was constructed at Los Alamos National Laboratory as a radiographic facility to provide dual-axis multi-time radiography support the US Stockpile Stewardship Program. DARHT 1 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">st</sup> has been operational since 1999 and providing excellent radiographs. 2 xmlns:xlink="http://www.w3.org/1999/xlink">nd</sup> construction project completed...