Template Matching on Vector Fields using Clifford Algebra

Due to the amount of flow simulation and measurement data, automatic detection, classification and visualization of features is necessary for an inspection. Therefore, many automated feature detection methods have been developed in recent years. However, one feature class is visualized afterwards in most cases, and many algorithms have problems in the presence of noise or superposition effects. In contrast, image processing and computer vision have robust methods for feature extraction and computation of derivatives of scalar fields. Furthermore, interpolation and other filter can be analyzed in detail. An application of these methods to vector fields would provide a solid theoretical basis for feature extraction. The authors suggest Clifford algebra as a mathematical framework for this task. Clifford algebra provides a unified notation for scalars and vectors as well as a multiplication of all basis elements. The Clifford product of two vectors provides the complete geometric information of the relative positions of these vectors. Integration of this product results in Clifford correlation and convolution which can be used for template matching on vector fields. Furthermore, for frequency analysis of vector fields and the behavior of vector-valued filters, a Clifford Fourier transform has been derived for 2 and 3 dimensions. Convolution and other theorems have been proved, and fast algorithms for the computation of the Clifford Fourier transform exist. Therefore the computation of Clifford convolution can be accelerated by computing it in Clifford Fourier domain. Clifford convolution and Fourier transform can be used for a thorough analysis and subsequent visualization of vector field

Relatório dos projetos concluídos 2009.

bitstream/item/58245/1/doc138.pd

Relatório dos projetos concluídos 2010.

bitstream/item/46830/1/Documento-144.pdfProjeto: 11.11.11.111

Relatório dos projetos concluídos 2011.

bitstream/item/79693/1/Doc-156.pdfProjeto/Plano de Ação: 11.11.11.111

Non scientific restrictions to poultry production: main global myth and beliefs.

Projeto/Plano de Ação: 11.11.11.111

Visual exploration of climate variability changes using wavelet analysis

Due to its nonlinear nature, the climate system shows quite high natural variability on different time scales, including multiyear oscillations such as the El Ni˜no Southern Oscillation phenomenon. Beside a shift of the mean states and of extreme values of climate variables, climate change may also change the frequency or the spatial patterns of these natural climate variations. Wavelet analysis is a well established tool to investigate variability in the frequency domain. However, due to the size and complexity of the analysis results, only few time series are commonly analyzed concurrently. In this paper we will explore different techniques to visually assist the user in the analysis of variability and variability changes to allow for a holistic analysis of a global climate model data set consisting of several variables and extending over 250 years. Our new framework and data from the IPCC AR4 simulations with the coupled climate model ECHAM5/MPI-OM are used to explore the temporal evolution of El Ni˜no due to climate change

Ciclo de vida de Alphitobius diaperinus Panzer (Coleoptera: Tenebrionidae) em laboratório.

Projeto/Plano de Ação: 11.11.11.111

Ciclo de vida de Alphitobius diaperinus Panzer (Coleoptera: Tenebrionidae): estudos preliminares.

Projeto/Plano de Ação: 11.11.11.111