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Nomenclatura Unesco > (33) Ciencias Tecnológicas

Mostrando recursos 161 - 180 de 2,145

161. A High Level Test Processor and Test Program Generator - Francisco Duarte; José Carlos Alves; José Machado da Silva; António Pinho; José Silva Matos
Embedded test within integrated systems allows to overcome some of the difficulties found when testing using only an external tester. The reutilization of a reconfigurable FPGA-like block that may exist in certain SoC systems, enables the implementation of on-chip test processors highly optimized to meet the specific requirements of the test procedure for each block. The fast reconfiguration of SRAM-based FPGA blocks allows sharing the same physical area among the set of different circuits that may be necessary to implement the on-chip test suite of the whole system. This paper addresses the high level generation of specific programmable processors for...

162. A Low-Power Oscillation Based LNA BIST Scheme - José Machado da Silva
Abstract—Test stimuli generation and power consumption are two issues that jeopardize the design of built-in self test schemes. The LNA testing approach presented herein relies on converting the amplifier into an oscillator and on using a low-power correlator to obtain a signature from the cross-correlation between the dynamic power supply current and the LNA’s output voltage. In test mode a high fault coverage is obtained together with a low power consumption, while avoiding an extra stimulus generator. No significant performance degradation results from the added test circuitry. Concerning the interface with the external tester, a digital signal is required to switch between normal and test modes, as well as a...

163. A Processor for Testing Mixed-Signal Cores in System-on-Chip - Francisco Duarte; José Machado da Silva; José Carlos Alves; António Pinho; José Silva Matos
This paper describes the design of a processor specific for testing cores embedded in system-on-chip. This processor, which can be implemented within a system's reconfigurable area, shall be responsible for scheduling and control test operations and perform preliminary data processing, as well as to provide the interface with an external tester. Building these test operations on-chip allows for simplifying external tester interface and to reduce testing time. The testing procedure and the infrastructure required to test an A/D converter is described as an example.

164. Visita a la Unidad de Recursos de Información Científica para la Investigación (URICI) de personal bibliotecario del Consejo Nacional de Ciencia y Tecnología de México (CONACYT) - Cottereau, Mario
El 28 de noviembre la URICI recibió la visita de un grupo de bibliotecarios y personal académico perteneciente al Consejo Nacional de Ciencia y Tecnología de México (CONACYT), organismo que abarca 27 instituciones de investigación que cubren los principales campos del conocimiento científico y tecnológico, agrupados en tres áreas: Desarrollo Tecnológico, Ciencias Exactas y Naturales y Ciencias Sociales y Humanidades. El CONACYT es una institución con grandes semejanzas con el CSIC por su estructura administrativa e implantación geográfica en todo el país.

165. Arte digital - Sánchez López, Antonio José
[ES] El ordenador es una herramienta de enorme potencial para el arte visual [Spalter99], tanto en el marco de la imagen estática, como en el contexto del video o imagen en movimiento. Las imágenes son fácilmente comprendidas por los humanos, motivo por el cual es un ámbito válido de trabajo creativo. Por otro lado, ocupa también a multitud de científicos del campo de la Visión por Computador en su búsqueda de técnicas para detectar y reconocer objetos. La tecnología digital, presenta la singularidad de la no existencia de un original único, de disponer del original en cualquier parte y ser...

166. Uma Meta-Heurística para o Problema da Programação de Projectos com Recursos Limitados - Mendes, J.J.M; Gonçalves, J. F.

167. Descoberta da topologia do sistema na ausência de sinais com redes neurais autoassociativas - Jakov Krstulovic; Vladimiro Miranda; Hrvoje Keko; Jorge Pereira

168. A comparative study of greywater from domestic and public buildings - Cristina Santos; Cristina Matos; Francisco Taveira Pinto

169. Classifier-based Cell Segmentation from Confocal Microscopy Images - Mónica Marcuzzo; Pedro Quelhas; Ana Campilho; Ana Maria Mendonça; Aurélio Campilho

170. Robust optical flow estimation - Sánchez Pérez, Javier; Monzón López, Nelson; Salgado de la Nuez, Agustín Javier
[EN] In this work, we describe an implementation of the variational method proposed by Brox et al. in 2004, which yields accurate optical flows with low running times. It has several benefits with respect to the method of Horn and Schunck: it is more robust to the presence of outliers, produces piecewise-smooth flow fields and can cope with constant brightness changes. This method relies on the brightness and gradient constancy assumptions, using the information of the image intensities and the image gradients to find correspondences. It also generalizes the use of continuous L1 functionals, which help mitigate the efect of...

171. A variational approach to camera motion smoothing - Álvarez León, Luis Miguel; Gómez Déniz, Luis; Henríquez Castellano, Pedro; Mazorra Manrique de Lara, Luis
[EN] In this paper we study a variational problem derived from a computer vision application: video camera calibration with smoothing constraint. By video camera calibration we meanto estimate the location, orientation and lens zoom-setting of the camera for each video frame taking into account image visible features. To simplify the problem we assume that the camera is mounted on a tripod, in such case, for each frame captured at time t , the calibration is provided by 3 parameters : (1) P(t) (PAN) which represents the tripod vertical axis rotation, (2) T(t) (TILT) which represents the tripod horizontal axis rotation...

172. List Scheduling Algorithm for Heterogeneous Systems by an Optimistic Cost Table - Hamid Arabnejad; Jorge Manuel Gomes Barbosa
Efficient application scheduling algorithms are important for obtaining high performance in heterogeneous computing systems. In this paper, we present a novel list-based scheduling algorithm called Predict Earliest Finish Time (PEFT) for heterogeneous computing systems. The algorithm has the same time complexity as the state-of-the-art algorithm for the same purpose, that is, O(v^2.p) for v tasks and p processors, but offers significant makespan improvements by introducing a look-ahead feature without increasing the time complexity associated with computation of an Optimistic Cost Table (OCT). The calculated value is an optimistic cost because processor availability is not considered in the computation. Our algorithm is only based on an OCT...

173. Detección y caracterización de estructuras de meso y submesoescala a partir de modelos de predicción oceánicos - Rubio Esparza, Álvaro

[ES] El proyecto trata sobre la detección y caracterización de estructuras oceánicas de mesoescala, concretamente, los giros. Estas estructuras son muy importantes a la hora del estudio de numerosos procesos físicos, químicos y biológicos que suceden en el medio oceánico. Para ello, se han estudiado otros sistemas relacionados, se ha creado una aplicación con la que los usuarios puedan caracterizar giros de forma sencilla, y una serie de herramientas automáticas de detección de giros. Por último se han realizado una serie de pruebas y comparativas de las herramientas desarrolladas para demostrar su eficacia y que éstas cumplen todos los objetivos...

174. Engineering intervention management using a probabilistic methodology for hot spot identification - Sara Ferreira; António Fidalgo Couto
A theoretical definition of a hotspot is any location that has a higher expected number of accidents than other similar locations as a result of local risk factors present at the location. This study presents an alternative approach to research regarding hot spot definition and identification based on a probabilistic model that defines the dependent variable as an indicator of a discrete choice. A binary choice model was used considering a binary dependent variable that differentiates a hot spot (category 1) from a safe (category 0) site set by the number of accidents per kilometer. To define these two categories,...

175. Hot-Spot Identification: a Categorical Binary Model Approach - António Fidalgo Couto
An alternative methodology is presented for hot-spot identification based on a probabilistic model. In this method, the ranking criterion for hot-spot identification conveys the probability of a site's being a hot spot or not being a hot spot. A binary choice model is used to link the outcome to a set of factors that characterize the risk of the sites under analysis on the basis of two categories (0/1) for the dependent variable. The proposed methodology consists of two main steps. After a threshold value for the number of accidents is set to distinguish hot spots from safe sites (Category...

176. Wildfire frecasting using an open source 3D multilayer geographical framework - Castrillón Santana, Modesto; Jorge, Pedro Antonio; Macías Casado, Adrián; Sánchez López, Antonio José; Sánchez Pérez, Javier; Suárez Rivero, José Pablo; Trujillo Pino, Agustín
[EN] This abstract describes the development of a wildfire forecasting plugin using Capaware. Capaware is designed as an easy to use open source framework to develop 3D graphics applications over large geographic areas offering high performance 3D visualization and powerful interaction tools for the Geographic Information Systems (GIS) community.

177. Wildfire prevention and management in a 3D virtual environment - Castrillón Santana, Modesto; Jorge, P. A.; López Rodríguez, Ignacio José; Macías Casado, Ignacio José; Martín Zerpa, David; Nebot Medina, Rafael Juan; Sabbagh Rodríguez, Izzat; Sánchez Pérez, Javier; Sánchez López, Antonio José; Suárez Rivero, José Pablo; Trujillo Pino, Agustín
[EN] This paper describes a wildfire forecasting application based on a 3D virtual environment and a fire simulation engine. A new open source framework is presented for the development of 3D graphics applications over large geographic areas offering high performance 3D visualization and powerful interaction tools for the Geographic Information Systems community. The application includes a remote module that allows simultaneous connection of several users for monitoring a real wildfire event. The user is enabled to simulate and visualize a wildfire spreading on the terrain under conditions of spatial information on topography and fuels along with weather and wind files.

178. Temporal constraints in large optical flow estimation - Salgado de la Nuez, Agustín Javier; Sánchez Pérez, Javier
[EN] The aim of this work is to propose a model for computing the optical flow in a sequence of images. We introduce a new temporal regularizer that is suitable for large displacements. We propose to decouple the spatial and temporal regularizations to avoid an incongruous formulation. For the spatial regularization we use the Nagel-Enkelmann operator and a newly designed temporal regularization. Our model is based on an energy functional that yields a partial differential equation (PDE). This PDE is embedded into a multipyramidal strategy to recover large displacements. A gradient descent technique is applied at each scale to reach...

179. CART application to image primitives tracking - Álvarez León, Luis Miguel; Henríquez Castellano, Pedro; Sánchez Pérez, Javier

[EN] [EN] In this paper we present a new method for image primitives tracking based on a CART (Classification and Regression Tree). Primitives tracking procedure uses lines and circles as primitives. We have applied the proposed method to sport event scenarios, specifically, soccer matches. We estimate CART parameters using a learning procedure based on RGB image channels. In order to illustrate its performance, it has been applied to real HD (High Definition) video sequences and some numerical experiments are shown. The quality of the primitives tracking with the decision tree is validated by the percentage error rates obtained and the...

180. Variational second order flow estimation for PIV sequences - Álvarez León, Luis Miguel; Castaño Moraga, Carlos Alberto; García, Miguel; Krissian, Karl; Mazorra Manrique de Lara, Luis; Salgado de la Nuez, Agustín Javier; Sánchez Pérez, Javier
[EN] We present in this paper a variational approach to accurately estimate simultaneously the velocity field and its derivatives directly from PIV image sequences. Our method differs from other techniques that have been presented in the literature in the fact that the energy minimization used to estimate the particles motion depends on a second order Taylor development of the flow. In this way, we are not only able to compute the motion vector field, but we also obtain an accurate estimation of their derivatives. Hence, we avoid the use of numerical schemes to compute the derivatives from the estimated flow...

 

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