INTRODUCTION: Most of the previous functional studies focus on the magnitude change of the MR signal. However, as well as the magnitude change, the phase change of the BOLD fMRI signal [1-3] and the frequency shift of the functional MR signal [4] have also been detected in human. Since no fMRI signal phase change should be detected if the fMRI signal is only consisted of extravascular signal an...

The change signal task is a variant of a two-alternative forced-choice (2AFC) task where the initial stimulus is superseded with the alternative stimulus (the change signal) at a delay on a proportion of trials. Taking advantage of the overlap in task requirements, we present a single model that can perform both tasks, and we validate the model using the empirical data from participants who per...

Signal detection in the analysis of blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) may be greatly hindered by cardiac pulsatility artifacts. Vessel pulsation, cerebrospinal fluid movement, and tissue deformation are all associated with the cardiac cycle and all can produce fMRI signal variance. Most cognitive fMRI studies do not utilize a method of cardiac-rela...

This work presents a principled system based on statistical signal processing for the detection of regions of motion in video and the determination of time instants when there are changes in activities. Currently, the detection of temporal changes in video detects different shots instead of changes in activities. Areas of activity are first found by processing higher order statistics of illumin...

The major challenge before the plant scientists is to develop strategies to increase the productivity of crop plants so as to feed the rapidly increasing global population. The increased anthropogenic activities have resulted in radical decrease of fertile land available for agricultural practices, and in addition, the impact of climate change, which poses environmental stress resulting in dras...

abstract successful presence of indian and pakistani rice in iran’s market due to having similar quality with the domestic rice, extensive advertisement, and good packaging has faced rice production in iran with a big challenge. assuming that the attractions of iranian consumers toward these imported rice varieties are a signal of changes in the preferences of the domestic consumers in favor of...

Blood oxygen level dependent (BOLD) contrast is influenced by some physiological factors such as blood flow and blood volume that can be a source of variability in fMRI analysis. Previous studies proposed to use the cerebrovascular response data to normalize or calibrate BOLD maps in order to reduce variability of fMRI data both among brain areas in single subject analysis and across subjects. ...

PURPOSE Signal detection methods have been used extensively in postmarket surveillance to identify elevated risks of adverse events associated with medical products (drugs, vaccines, and devices). However, current popular disproportionality methods ignore useful information such as trends when the data are aggregated over time for signal detection. METHODS In this paper, we applied change poi...

Change detection between two images is challenging and needed in a wide variety of imaging applications. Several approaches have been yet developed, especially methods based on difference image. In this paper, we propose an original patch-based Markov modeling framework to detect spatial irregularities in the difference image with low false alarm rates. Experimental results show that the propos...

abstract: gridlock is an extreme traffic state where vehicle cannot move at all. this research studies the development of gridlock by theoretical and numerical analysis. it is shown that the development of gridlock can be divided into several stages. the core of the development is the evolution of congestion loop. a congestion loop is comprised of a number of consecutively connected spillover l...