Search results for "Virtual"
showing 10 items of 1485 documents
Linearizing Auditory Distance Estimates by Means of Virtual Acoustics
2008
Auditory distance estimates are not linearly related to physical distances: people tend to overestimate close physical distances, and underestimate far distances [I]. We have modeled a virtual listening environment whose objective is to provide a linear relationship between perceived and physical distance. The simulated environment consists of a trapezoidal membrane with specific absorbing properties at the boundaries. A physics-based model simulates acoustic wave propagation in this virtual space and provides auditory distance cues, namely intensity and direct-to-reverberant energy ratio. Simulations predict the linearity of the psychophysical function relating physical distance to perceiv…
Increasing GP Computing Power for Free via Desktop GRID Computing and Virtualization
2009
This paper presents how it is possible to increase the Genetic Programming (GP) Computing Power (CP) for free, via Volunteer Computing (VC), using the well known framework BOINC plus a new ``virtualization'' layer which adds all the benefits from the virtualization paradigm. Two different experiments, employing a standard GP tool and a complex GP system, are performed --with distributed PCs over several cities-- to show the free achieved CP by means of VC, without the necessity of modifying or adapting the original GP source code. The methodology can be easily extended to Evolutionary Algorithms (EAs).
Virtual Reality Based Simulators for Neurosurgeons - What We Have and What We Hope to Have in the Nearest Future
2018
High levels of manual skills, good visual-motor coordination, excel‐lent imagination and spatial awareness are the main factors determining the success of neurosurgeons. Proficiency in neurosurgical skills used to be acquired through hands-on training in cadaver labs and in real operating theatres under master neurosurgeon supervision. Most recently, virtual reality (VR) and augmented reality (AR) computer simulations have also been considered as tools for education in the neurosurgical training. The authors review existing solutions and present their own concept of a simulator which could become the useful tool for planning, simulation and training of a specific neurosurgical procedure usi…
A method to transform a nonlocal model into a gradient one within elasticity and plasticity
2014
Abstract A method based on the principle of the virtual power (PVP) is presented, by which a mechanical problem of nonlocal elasticity, or plasticity, is transformed into one of gradient nature. Different Taylor series expansion techniques are applied to the driving local strain fields of the nonlocal problem, either full spatial expansion within the bulk volume, or uni-directional expansion along the normal to the thin boundary layer. This, at the limit when the boundary layer thickness tends to zero, makes the PVP of the nonlocal model transform itself into one featuring a counterpart gradient model. Also, for a class of “associated” nonlocal and gradient elasticity models (i.e. the kerne…
Using an adaptive display for the treatment of emotional disorders
2006
A preliminary study on the use of an adaptive display for treating emotional disorders is presented. This adaptive display (named EMMA) varies the contents that are presented depending on the emotions of the user at each moment. The application has been designed to help in the treatment of Post-Traumatic Stress Disorder (PTSD) and Adjustment Disorder (AD). The specific objective of the present work is to test the effectiveness of this adaptive display, specifically the acceptance of the treatment by patients. EMMA's tools are compared with the standard of care for PTSD and AD. Results showed differences only for the variable aversiveness. Participants in the EMMA condition evaluated the tre…
Probabilistic analysis of truss structures with uncertain parameters (virtual distortion method approach)
2004
A new approach for probabilistic characterization of linear elastic redundant trusses with uncertainty on the various members subjected to deterministic loads acting on the nodes of the structure is presented. The method is based on the simple observation that variations of structural parameters are equivalent to superimposed strains on a reference structure depending on the axial forces on the elastic modulus of the original structure as well as on the uncertainty (virtual distortion method approach). Superposition principle may be applied to separate contribution to mechanical response due to external loads and parameter variations. Statically determinate trusses dealt with the proposed m…
Molecular topology applied to the discovery of 1-benzyl-2-(3-fluorophenyl)-4-hydroxy-3-(3-phenylpropanoyl)-2H-pyrrole-5-one as a non-ligand-binding-p…
2014
We report the discovery of 1-benzyl-2-(3- fluorophenyl)-4-hydroxy-3-(3-phenylpropanoyl)-2H-pyrrole- 5-one as a novel non-ligand binding pocket (non-LBP) antagonist of the androgen receptor (AR) through the application of molecular topology techniques. This compound, validated through time-resolved fluorescence resonance energy transfer and fluorescence polarization biological assays, provides the basis for lead optimization and structure−activity relationship analysis of a new series of non-LBP AR antagonists. Induced-fit docking and molecular dynamics studies have been performed to establish a consistent hypothesis for the interaction of the new active molecule on the AR surface. Refereed/…
Antiproliferative properties and g-quadruplex-binding of symmetrical naphtho[1,2-b:8,7-b’]dithiophene derivatives
2021
Background: G-quadruplex (G4) forming sequences are recurrent in telomeres and promoter regions of several protooncogenes. In normal cells, the transient arrangements of DNA in G-tetrads may regulate replication, transcription, and translation processes. Tumors are characterized by uncontrolled cell growth and tissue invasiveness and some of them are possibly mediated by gene expression involving G-quadruplexes. The stabilization of G-quadruplex sequences with small molecules is considered a promising strategy in anticancer targeted therapy. Methods: Molecular virtual screening allowed us identifying novel symmetric bifunctionalized naphtho[1,2-b:8,7-b’]dithiophene ligands as interesting ca…
<title>Face modeling: a real-time embedded implementation of a stereovision algorithm</title>
2001
The problem to acquire 3D data of human face can be applied in face recognition, virtual reality, and many other applications. It can be solved using stereovision. This technique consistes in acquiring data in three dimensions from two cameras. The aim is to implement an algorithmic chain which makes it possible to obtain a three-dimensional space from two two-dimensional spaces: two images coming from the two cameras. Several implementations have already been considered. We propose a new simple realtime implementation, based on a multiprocessor approach (FPGA-DSP) allowing to consider an embedded processing. Then we show our method which provides depth map of face, dense and reliable, and …
A Theoretical Learning Model Combining Stochastic Cellular Automata and Economic Indicators to Simulate Land Use Change
2015
The study of change in land use has been included in territorial planning to inform spatial planners and policy makers of the possible developments they face in order to optimize future management decisions. In this paper the authors present the core of an original learning model coupling stochastic Cellular Automata and economic indicators to simulate the land use change. This model is an important step in building an “environmental virtual laboratory” to explore, explain and forecast land use change.