Search results for "Spatial"

Modifying auditory perception with prisms? Aftereffects of prism adaptation on a wide auditory spectrum in musicians and nonmusicians

2021

Prism adaptation consists of pointing to visual targets while wearing prisms that shift the visual field laterally. The aftereffects are not restricted to sensorimotor level but extend to spatial cognition. There is a link between spatial representation and auditory frequency, with an association of low frequencies on the left side and high frequencies on the right side of space. The present study aimed first at evaluating the representation of auditory frequencies on a wide range of frequencies in musicians and nonmusicians. We used the ‘auditory interval bisection judgment’ within three auditory intervals. The results showed a pseudoneglect behavior in pretest in musicians and nonmusician…

A Comparative Study on Fuzzy-Clustering-Based Lip Region Segmentation Methods

2011

As the first step of many lip-reading or visual speaker authentication systems, lip region segmentation is of vital importance. And fuzzy clustering based methods have been widely used in lip segmentation. In this paper, four fuzzy clustering based lip segmentation methods have been elaborated with their underlying rationale. Experiments have been carried out evaluate their performance comparatively. From the experimental results, SFCM has the best efficiency and FCMST has the best segmentation accuracy.

THE INFLUENCE OF SPATIAL COGNITION IN THEORY OF MIND AND CENTRAL COHERENCE TASKS: STUDY IN AUTISM

Autism Spectrum Disorder (ADS) is a severe developmental disability characterized by impairments in social interaction and communicative skills. Despite a growing research interest in the field, the causes of these impairments remain unknown. Two lines of research, Theory of Mind (ToM) and Central Coherence (CC), using experimental tasks such as visuo-spatial perspective Taking (VPT) and the local and global levels have suggested that visuo-spatial attention and spatial variables in the self-versus other recognition, may be the basis of the cognitive processes underlying social interaction. According to spatial attention, such as observed in the Unilateral spatial neglect (USN) may contribu…

Autocorrelation Metrics to Estimate Soil Moisture Persistence From Satellite Time Series: Application to Semiarid Regions

2021

Satellite-derived soil moisture (SM) products have become an important information source for the study of land surface processes in hydrology and land monitoring. Characterizing and estimating soil memory and persistence from satellite observations is of paramount relevance, and has deep implications in ecology, water management, and climate modeling. In this work, we address the problem of SM persistence estimation from microwave sensors using several autocorrelation metrics that, unlike traditional approaches, build on accurate estimates of the autocorrelation function from nonuniformly sampled time series. We show how the choice of the autocorrelation estimator can have a dramatic impac…

Application of Radio Environment Map Reconstruction Techniques to Platoon-based Cellular V2X Communications

2020

Vehicle platoons involve groups of vehicles travelling together at a constant inter-vehicle distance, with different common benefits such as increasing road efficiency and fuel saving. Vehicle platooning requires highly reliable wireless communications to keep the group structure and carry out coordinated maneuvers in a safe manner. Focusing on infrastructure-assisted cellular vehicle to anything (V2X) communications, the amount of control information to be exchanged between each platoon vehicle and the base station is a critical factor affecting the communication latency. This paper exploits the particular structure and characteristics of platooning to decrease the control information exch…

Decomposing and Interpreting Spatial Effects in Spatio-Temporal Analysis: Evidences for Spatial Data Pooled Over Time

2017

Empirical applications using individual spatial data pooled over time usually neglect the fact that such data are not only spatially localized: they are also collected over time, i.e. temporally localized. So far, little effort has been devoted to proposing a global way for dealing with spatial data (cross-section) pooled over time, such as real estate transactions, business start-up, crime and so on. However, the spatial effect, in such a context, can be decomposed in two different components: a multidirectional spatial effect (same time period) and a unidirectional spatial effect (previous time period). Based on real estate literature, this chapter presents different spatio-temporal autor…

A Comprehensive Spatiotemporal Framework for Hedonic Pricing: Integrating the Comparable Sales Approach and Minimizing Spatial Omitted Variable Bias

2019

This paper develops a theoretical and methodological framework that integrates Hedonic Pricing (HP), grid comparable sales approach (CSA), and nearest neighbors into a general spatiotemporal specification. By explicitly providing a theoretical justification for introducing spatial (or spatiotemporal) econometrics to HP, this approach is not only relevant to house price forecasting and automated valuation models (AVM) but also to valuing environmental goods capitalized in housing and to all other fields employing house pricing models. The resulting econometric CSA and spatiotemporal Durbin models provide higher prediction accuracy and reliability to alternatives by reducing the spatially-del…

Inverse problem for tripotential measures in the study of buried cavities

1996

This paper presents a solution to the inverse electrical problem for the interpretation of apparent resistivity anomalies due to empty buried cavities of quasi-spherical shape when tripotential measures are carried out. The anomalies of the apparent resistivities ra,rb andrg,and the composed resistivitiesrmand rt were previously calculated for a sufficient class of spherical models of resistivity anomalies. Then, for the whole class of models, some functionals of spatial distribution of the apparent and composed resistivity were identified and analyzed. They represent the average characteristics of the anomalies and, depending in a simple way on the fundamental parameters of the sources of …

Ebselen prevents chronic alcohol-induced rat hippocampal stress and functional impairment

2007

Background: Most of the previously published data suggest a role for oxidative or nitrosative stress in ethanol-induced nervous system damage. Moreover, ethanol is able to impair learning abilities in adult mammalian brain, a process suggested to be directly related to hippocampal neurogenesis. Ebselen, a synthetic compound with antioxidant properties, is able to prevent ethanol-induced impairment of neurogenesis in adult rats. The aim of the present work was to further demonstrate the ability of ebselen to prevent biochemical alterations, and preserve long-term potentiation (LTP) and learning abilities, in the hippocampus of chronic alcoholic adult rats. Methods: Biochemical markers of oxi…

Microlensing Discovery of a Population of Very Tight, Very Low Mass Binary Brown Dwarfs

2013

Although many models have been proposed, the physical mechanisms responsible for the formation of low-mass brown dwarfs (BDs) are poorly understood. The multiplicity properties and minimum mass of the BD mass function provide critical empirical diagnostics of these mechanisms. We present the discovery via gravitational microlensing of two very low mass, very tight binary systems. These binaries have directly and precisely measured total system masses of 0.025 M [SUB]⊙[/SUB] and 0.034 M [SUB]⊙[/SUB], and projected separations of 0.31 AU and 0.19 AU, making them the lowest-mass and tightest field BD binaries known. The discovery of a population of such binaries indicates that BD binaries can …