Study of Subjective and Objective Quality Assessment of Audio-Visual Signals.

The topics of visual and audio quality assessment (QA) have been widely researched for decades, yet nearly all of this prior work has focused only on single-mode visual or audio signals. However, visual signals rarely are presented without accompanying audio, including heavy-bandwidth video streaming applications. Moreover, the distortions that may separately (or conjointly) afflict the visual and audio signals collectively shape user-perceived quality of experience (QoE).

Evaluation of Different Types of Filters in Magnetic Resonance Imaging Using Compressive Sensing with Pre-Filtering.

Magnetic resonance imaging (MRI) machines allow one to acquire medical images based on static and variable magnetic fields, in such a way as to reveal the interior of human organs. To acquire images with good quality, MRI machines often demand a high number of measurements, which often require long acquisition times. Therefore, an important topic of research consists of developing acquisition methods that reduce the number of measurements and, consequently, the time required to acquire an MRI image.

Detection of Gabor patterns of different sizes, shapes, phases and eccentricities.

Contrast thresholds of vertical Gabor patterns were measured as a function of their eccentricity, size, shape, and phase using a 2AFC method. The patterns were 4 c/deg and they were presented for 90 or 240 ms. Log thresholds increase linearly with eccentricity at a mean rate of 0.