Mathematical analysis of the Accordion Grating illusion: A differential geometry approach to introduce the 3D aperture problem

A new motion illusion based on competition between two kinds of motion processing units: The Accordion Grating

Parametric psychophysical investigations are reported for two related illusory effects that occur when viewing an elementary square-wave grating while making "back and forth" head movements along the projection line. Observers report a non-rigid distortion of the pattern, including: (i) an expansion in a direction perpendicular to the stripes, and (ii) a perceived curvature of the stripes. We i...

Direct Aperture Optimization for Intensity Modulated Radiation Therapy: Two Calibrated Metaheuristics and Liver Cancer Case Study

Integrated treatment planning for cancer patients has high importance in intensity modulated radiation therapy (IMRT). Direct aperture optimization (DAO) is one of the prominent approaches used in recent years to attain this goal. Considering a set of beam directions, DAO is an integrated approach to optimize the intensity and leaf position of apertures in each direction. In this paper, first, ...

Application of Convolution of Daubechies Wavelet in Solving 3D Microscale DPL Problem

In this work, the triple convolution of Daubechies wavelet is used to solve the three dimensional (3D) microscale Dual Phase Lag (DPL) problem. Also, numerical solution of 3D time-dependent initial-boundary value problems of a microscopic heat equation is presented. To generate a 3D wavelet we used the triple convolution of a one dimensional wavelet. Using convolution we get a scaling function ...

The Drifting Edge Illusion: A stationary edge abutting an oriented drifting grating appears to move because of the ‘other aperture problem’

We describe the Drifting Edge Illusion (DEI), in which a stationary edge appears to move when it abuts a drifting grating. Although a single edge is sufficient to perceive DEI, a particularly compelling version of DEI occurs when a drifting grating is viewed through an oriented and stationary aperture. The magnitude of the illusion depends crucially on the orientations of the grating and apertu...

The novelty of the "Accordion Grating Illusion"