Search results for " Computer Science"
showing 10 items of 3983 documents
Variable Neighborhood Search for the Vertex Separation Problem
2012
The vertex separation problem belongs to a family of optimization problems in which the objective is to nd the best separator of vertices or edges in a generic graph. This optimization problem is strongly related to other well-known graph problems; such as the Path-Width, the Node Search Number or the Interval Thickness, among others. All of these optimization problems are NP-hard and have practical applications in VLSI, computer language compiler design or graph drawing. Up to know, they have been generally tackled with exact approaches, presenting polynomial-time algorithms to obtain the optimal solution for speci c types of graphs. However, in spite of their practical applications, these…
Combining fuzzy C-mean and normalized convolution for cloud detection in IR images
2009
An important task for the cloud monitoring in several frameworks is providing maps of the cloud coverage. In this paper we present a method to detect cloudy pixels for images taken from ground by an infra-red camera. The method is a three-steps algorithm mainly based on a Fuzzy C-Mean clustering, that works on a feature space derived from the original image and the output of the reconstructed image obtained via normalized convolution. Experiments, run on several infra-red images acquired under different conditions, show that the cloud maps returned are satisfactory. © 2009 Springer Berlin Heidelberg.
Towards efficient inductive synthesis of expressions from input/output examples
1993
Our goal through several years has been the development of efficient search algorithm for inductive inference of expressions using only input/output examples. The idea is to avoid exhaustive search by means of taking full advantage of semantic equality of many considered expressions. This might be the way that people avoid too big search when finding proof strategies for theorems, etc. As a formal model for the development of the method we use arithmetic expressions over the domain of natural numbers. A new approach for using weights associated with the functional symbols for restricting search space is considered. This allows adding constraints like the frequency of particular symbols in t…
On the contractile mechanism of insect fibrillar flight muscle. IV. A quantitative chemo-mechanical model.
1975
Ausgehend von detaillierten Vorstellungen zur Kinetik der myofibrillaren ATPase und der Ankopplung der Enzymwirkung an die Mechanik der Myosinbruckenzyklen wird ein quantitatives chemo-mechanisches Modell fur den fibrillaren Insektenflugmuskel vorgeschlagen. Mit der Wahl eines einheitlichen Parametersatzes gelingt es praktisch alle bisher in der Literatur beschriebenen Resultate zu simulieren. Dazu gehoren der verzogerte Spannungsaufbau bei rechteckformigen und sinusoidalen Langenanderungen, charakteristische Nichtlinearitaten in den oszillatorischen Langen-Spannungsschleifen, die Aktivierung der ATPase Aktivitat durch statische und dynamische Dehnung, der proportionale Anstieg des Wirkungs…
Indoor Scene Understanding using Non-Conventional Cameras
2020
Humans understand environments effortlessly, under a wide variety of conditions, by the virtue of visual perception. Computer vision for similar visual understanding is highly desirable, so that machines can perform complex tasks by interacting with the real world, to assist or entertain humans. In this regard, we are particularly interested in indoor environments, where humans spend nearly all their lifetime.This thesis specifically addresses the problems that arise during the quest of the hierarchical visual understanding of indoor scenes.On the side of sensing the wide 3D world, we propose to use non-conventional cameras, namely 360º imaging and 3D sensors. On the side of understanding, …
Control points deployment in an Intelligent Transportation System for monitoring inter-urban network roadway
2022
Abstract The constant evolution of transportation systems and traffic in developing countries is nowadays confronted with a problem of road safety and therefore of a high accident rate, especially in the context of inter-urban road transport. In this work, we propose a communication architecture for an Intelligent Transport System (ITS) to provide surveillance in an inter-urban transport network in the context of developing countries. We introduce two types of control points: Relay Control Points (RCP) and Treatment Control Points (TrCP). We also designed two multi-objective models for the deployment of these points. In order to ensure good coverage, to minimize the cost of installation and…
Télécollaboration asymétrique en réalité virtuelle
2016
National audience; Nous présentons une première étude de combinaison de deux systèmes asymétriques de réalité virtuelle dans un contexte de travail collaboratif : un système de type CAVE et un casque immersif. L’architecture, de type serveur-client, permet une collaboration entre plusieurs utilisateurs. Les expériences sur une tâche de construction de puzzles en un temps limité, seul et en collaboration, montrent que l’utilisation combinée de systèmes asymétriques CAVE et casques permet d’améliorer les performances des utilisateurs. Par ailleurs les utilisateurs préfèrent le travail en collaboration et sont plus efficaces ensemble. Ces résultats ouvrent des perspectives intéressantes de com…
SimuRed: A flit-level event-driven simulator for multicomputer network performance evaluation
2009
The interconnection network is one of the most important multicomputer components, since it has a great impact on global system performance. Many models and simulators have been proposed to evaluate network performance. This paper presents SimuRed, an event-driven flit-level, cycle-accurate simulator to evaluate different orthogonal network configurations. The core of the simulator has been designed to be expandable and portable to different situations. Some of the advantages of this simulator over other similar tools are its visual interface, its fast execution and its simplicity. Moreover, it is multiplatform and its source code versions (C++ and Java) are freely available under GNU open-…
Influence of interaction techniques o n VIMS in virtual environments : estimation and prediction
2014
Understanding oculo-vestibular dynamics during sensory rearrangement in the central nervous system plays an extremely important role in better understanding human perception, and improves the technology in many engineering fields. Besides, the sensory conflict that occurs between ocular, vestibular and proprioception during sensory rearrangement at certain occasions might adversely affect the user performance in a wide variety of domains including flight/car simulators, scale-one 3D systems, large-scale displays, serious games, and so on. Therefore, knowing the condition in which the sensory conflict happens has a great deal of importance. This study aims at understanding the nature of sens…
Current modulation induced stability in laser diode under high optical feedback strength
2021
The back-reflection of emitted laser beam (optical feedback, also know as selfmixing) from various external interfaces are sufficient to cause instability, and prohibiting its use in various fields such as communication, spectroscopy, imaging to name a few. So it is desirable to study the laser dynamics and the conditions causing it to be stable in spite of strong optical feedback. With the aid of mathematical formulation, simulation and backed by experimental evidences, it is demonstrated that the frequency deviation of the laser emission due to current (intensity) modulation alters the dynamic state and boundary conditions of the system such that even under large optical feedback strength…