Visual Phenomena

Investigating CAPTCHAs Based on Visual Phenomena

We propose and evaluate several novel types of CAPTCHAs (test to tell computers and humans apart) that exploit characteristics of the human visual system. Perceptions caused by the effect of lightness constancy or grouping phenomena due to transparent motion are hard to emulate on computers and may thus provide novel authentication mechanisms.

Visual Modeling and Simulation of Multiscale Phenomena

RAHUL NARAIN: Visual Modeling and Simulation of Multiscale Phenomena (Under the direction of Ming C. Lin) Many large-scale systems such as human crowds, fluids, and granular materials exhibit complicated motion at many different scales, from a characteristic global behavior to important small-scale detail. Such multiscale systems are computationally expensive for traditional simulation techniqu...

Visuelle Welt: a Windows program for demonstrating visual-perception phenomena.

The Windows program Visuelle Welt allows the demonstration of various visual phenomena such as geometrical-optical illusions, subjective contours, apparent movement, and Gestalt principles. One of the program's most interesting features is that the illusion-inducing context can be switched off, and in addition for many phenomena parameters can be varied interactively.

Implications of Visual Attention Phenomena for Models of Preferential Choice

We use computational modeling to examine the ability of evidence accumulation models to produce the reaction time (RT) distributions and attentional biases found in behavioral and eye-tracking research. We focus on simulating RTs and attention in binary choice with particular emphasis on whether different models can predict the late onset bias (LOB), commonly found in eye movements during choic...

Visual Simulation of Refraction Phenomena in the Earth?s Atmosphere