Wavelets Theory
Mostrando 1-12 de 16 artigos, teses e dissertações.
-
1. Matrix Damage Detection in Laminated Composite Structures by Discrete and Continuous Wavelet Transforms Using Vibration Modes
ABSTRACT: In this paper it was sought to enhance the potential damage detection, location and quantification of the Discrete and Continuous Wavelet Transforms in thin damaged laminated composite plates by a signal derived from vibration modes. To evaluate the ability of both transforms in the damage prognostic it was also proposed the use of Damage Indexes.
J. Aerosp. Technol. Manag.. Publicado em: 21/09/2017
-
2. Esquemas de aproximação em multinível e aplicações / Multilevel approximation schemes and applications
O objetivo desta tese é desenvolver algoritmos baseados em malhas e bases funcionais inovadoras usando técnicas de multiescala para aproximação de funções e resolução de problemas de equações diferenciais. Para certas classes de problemas, é possível incrementar a eficiência dos algoritmos de multiescala usando bases adaptativas, associadas a ma
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/12/2011
-
3. Processamento de sinais de descargas parciais em tempo real com base em wavelets e seleção de coeficientes adaptativa espacialmente
On-line partial discharge (PD) analysis is a highly pursued feature due to the economy related to scheduled shutdowns, disassembling and transport. Nevertheless, on-site PD measurements are frequently limited by interferences found in high-voltage facilities, a situation that imposes the continued development of PD signal processing methods. In the last year
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 04/11/2011
-
4. Compressão de imagens digitais combinando técnicas wavelet e wedgelet no ambiente de comunicações móveis / Digital image compression combining wavelet and wedgelet techniques in mobile communication environment
Os avanços em telecomunicações e o desenvolvimento dos equipamentos digitais impulsionaram diversas áreas de pesquisa relacionadas à codificação e compressão de imagens. Dentre as áreas de atuação destacam-se as aplicações para dispositivos móveis (celulares, smartphones, iPhones, iPads entre outros), que se caracterizam por baixas taxas de tra
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 07/07/2011
-
5. A novel method for generating scale space kernels based on wavelet theory
The linear scale-space kernel is a Gaussian or Poisson function. These functions were chosen based on several axioms. This representation creates a good base for visualization when there is no information (in advanced) about which scales are more important. These kernels have some deficiencies, as an example, its support region goes from minus to plus infini
Publicado em: 2010
-
6. Impacto da utilização de tecnicas de lifting explorando diferença entre ferramentas interpretada e compilada na velocidade computacional da codificação wavelet de imagens estaticas / Impact of using lifting techniques to explore the differences between interpreted and compiled tools in the computational speed of wavelet static image coding
The field of analysis and compression of images has been received special attention of the scientific community because of including in the main systems of digital TV, satellite communications and mobile communications. In this context, the Discrete Transform Wavelet (TWD) arise how a powerful tool and its many advantages allowed your insertion in important
Publicado em: 2009
-
7. Banco de filtros e wavelets sobre corpos finitos
Filter banks and wavelets are tools of Engineering, dened over complex elds, with many applications. This dissertation introduces the theory of lter banks and wavelets dened over nite elds, over cyclical and noncyclical structures. The problem of dening two-channel lter banks and wavelet decompositions over elds of characteristic two was solved, thereby prov
Publicado em: 2008
-
8. Estudo da transformada rápida wavelet e sua conexão com banco de filtros
In this work we presented an exhibition of the mathematical theory of orthogonal compact support wavelets in the context of multiresoluction analysis. These are particularly attractive wavelets because they lead to a stable and very efficient algorithm, that is Fast Transform Wavelet (FWT). One of our objectives is to develop efficient algorithms for calcula
Publicado em: 2008
-
9. TRATAMENTO E COMPRESSÃO BASEADA EM WAVELETS PARA DADOS ADQUIRIDOS POR SENSORES / TREATMENT AND WAVELET-BASED COMPRESSION OF SENSOR DATA
This dissertation introduces a strategy to develop a compression method for sensor data inspired on the JPG2000 techniques. The strategy adopted processes data streams much in the same way as signal processing. Due to the unstable nature of sensor data, noise is added to the original signal. This noise is detected and treated while the signal is cleaned and
Publicado em: 2007
-
10. Aproximação de nuvens de pontos de dados por meio de superfícies de Bézier
The computational and empirical modelling of geophysical phenomena, such as F region zonal plasma drifts, is a basic tool for the understanding and forecasting of effects that have great social-economic impact on the human activities. This work proposes, develops and implements a model, based on Computer Aided Geometric Design techniques, to F region zonal p
Publicado em: 2007
-
11. AproximaÃÃo de nuvens de pontos de dados por meio de superfÃcies de BÃzier
The computational and empirical modelling of geophysical phenomena, such as F region zonal plasma drifts, is a basic tool for the understanding and forecasting of effects that have great social-economic impact on the human activities. This work proposes, develops and implements a model, based on Computer Aided Geometric Design techniques, to F region zonal p
Publicado em: 2007
-
12. Métodos híbridos para reconstrução tomográfica de imagens usando POCS e teoria da estimação / Hybrid methods for tomographic image reconstruction using POCs and estimation theory
Nesta tese é apresentado um novo método de reconstrução de imagens, por tomografia de transmissão, de projeções sujeitas a ruído na contagem de fótons. O método de reconstrução selecionado utiliza a técnica POCS (Projections Onto Convex Sets). A estimação das projeções originais a partir das observações ruidosas se dá por meio de quatro m
Publicado em: 2007