Joao Dovicchi - Academia.edu (original) (raw)

Papers by Joao Dovicchi

In this paper authors present a didactic method for teaching Data Structures on Computer Science ... more In this paper authors present a didactic method for teaching Data Structures on Computer Science undergraduate course. An approach using functional along with procedural languages (Haskell and ANSI C) is presented, and adequacy of such a method is discussed. Authors are also concerned on how functional language can help students to learn fundamental concepts and acquire competence on data typing and structure for real programming.

Anais de XXXIII Simpósio Brasileiro de Telecomunicações, 2015

Resumo-O uso de imagens de alta definição tem, via de regra, um custo elevado enquanto o uso de i... more Resumo-O uso de imagens de alta definição tem, via de regra, um custo elevado enquanto o uso de imagens de resolução menor tem custo acessível e necessita de ampliação. Este trabalho apresenta uma metodologia que envolve algumas ferramentas matemáticas aplicadas ao tratamento de imagens, para ampliação de imagens que evite o deslocamento ou a deformação dos pontos em espaços georreferenciados. Neste, propõem-se o estudo de interpolações multivariadas, combinando-se Séries de Fourier e polinômios de Chebyshev para filtragem. Além, da combinação com algoritmos de correção de cor, luminosidade e intensidade, por esses apresentarem resultados que possibilitam o tratamento do problema. Palavras-Chave-Ampliação de imagem, georreferenciamento, Resolução Multiescalonada, superresolução de imagem.

Compression and cryptography of digital data for network transmission using digi tal audio signal... more Compression and cryptography of digital data for network transmission using digi tal audio signals and its wavelet tranforms is described in this paper. Wavelts are mathematical functions which can amplify data intervals, splitting them into different segments off different frequencies. This treatment allows us to perfo rm data analysis and compression on each corresponding scale. A Wavelet transfor m in a space of some specific data function can sparsely represent each subspace of this function in the "time-frequency" domain. This property allows u s to use it for data compression, and once this compression is biorthogonally dependent of the filter coefficients it can be used as a cryptographic tool where those coefficients can represent pairs of public and pr ived keys. In this work we describe a new method to compress and encrypt digital data, simultaneously, for transmission over a network environment. Although results were yelded for digital audio data the method can ...

Compression and cryptography of digital data for network transmission using digi tal audio signal... more Compression and cryptography of digital data for network transmission using digi tal audio signals and its wavelet tranforms is described in this paper. Wavelts are mathematical functions which can amplify data intervals, splitting them into different segments off different frequencies. This treatment allows us to perfo rm data analysis and compression on each corresponding scale. A Wavelet transfor m in a space of some specific data function can sparsely represent each subspace of this function in the "time-frequency" domain. This property allows u s to use it for data compression, and once this compression is biorthogonally dependent of the filter coefficients it can be used as a cryptographic tool where those coefficients can represent pairs of public and pr ived keys. In this work we describe a new method to compress and encrypt digital data, simultaneously, for transmission over a network environment. Although results were yelded for digital audio data the method can ...

ABSTRACT In this paper authors present a didactic method for teaching Data Structures on Computer... more ABSTRACT In this paper authors present a didactic method for teaching Data Structures on Computer Science undergraduate course. An approach using func-tional along with procedural languages (Haskell and ANSI C) is presented, and adequacy of such a method is discussed. Authors are also concerned on how functional language can help students to learn fundamental concepts and acquire competence on data typing and structure for real programming.

Anais do II TecEAD

... Page 6. [5] DIXOT, S. & YE, Y. 2001.“Streamlining the Internet-Fiber Connection”, IEEE Sp... more ... Page 6. [5] DIXOT, S. & YE, Y. 2001.“Streamlining the Internet-Fiber Connection”, IEEE Spectrum, 38 (4), (April), pp.52-57. [6] GILLIGAN,R; THOMSON, S.; BOUND, J. e STEVENS, W. “Basic Socket Interface Extensions for IPv6”, RFC 2133, Apr. 1977. ...

ABSTRACT Using the octave chromatic division (2i/12) and the difference between two tones (22/12 ... more ABSTRACT Using the octave chromatic division (2i/12) and the difference between two tones (22/12 - 21/12 ) we define a! and p in Pollen’s parametric equations to calculate new wavelet coefficients. We first calculate 4 coefficients, using cy = 21/12 and ,8 = 0 and then we use Q = 21/12 and p = 22/12 - 21/12 for definition of 6 coefficients. In this paper, we describe its calculation, and show results yelded in direct and inverse transform of musical signals.

Resumo A s audio-digital tem sido um dos principais objetos de pesquisa na area de processamento ... more Resumo A s audio-digital tem sido um dos principais objetos de pesquisa na area de processamento digital de sinais. In umeros algoritmos de ltros, m etodos de s ann alise e convers~ ao A/D t^ em surgido recentemente. Os soostica-dos circu de processamento de som (placas de som) associados aos velozes processadores e a programas espec softwares espec O Sapphire e um compilador ac ustico desenvolvido por Finnis, implementado por Krzystoo (Linux) e Dovicchi (IBM-AIX) e que se tornou bastante popular. O programa usa um arquivo texto escrito na Linguagem Sapphire Geraa c~ ao de m usica (score) e ger^ encia instrumental; 3) Processamento de sinais, atrav es de ltros em eventos pr e-amostrados. O Sapphire usa o conceito de Ray-Tracing e oferece a possibilidade de inserir sons previamente compilados ou amostrados, nos scripts, utilizando geradores de envelope sonoro, osciladores e ltros digitais. Abstract Digital Audio Synthesis is becoming one of the top research points in the Digital Sign...

International Symposium on Signal Processing and Its Applications, 2005

In this paper, authors present a formal description of the algorithm for the construction of N-pa... more In this paper, authors present a formal description of the algorithm for the construction of N-parametric equations, which provides the attainment of any set of dilation coefficients from a set of N angles that sum /2. These coefficients can be used to construct any dimensional Wavelet filter bank to be applied to analysis and reconstruction of specific signal data.

This paper presents the description of a formal mathematical and computing method of Discrete Wav... more This paper presents the description of a formal mathematical and computing method of Discrete Wavelet Trans-form (DWT) combined with auto-correlation power spectrum. Detail segments (high-pass) of the first and second scale level of DWT ("lifting scheme") are convoluted using auto-correlation to achieve a more precise identification of cardiopathies which can be detected and represented for automated analysis due to power spectra differences. This study shows how ECG signals of normal and some cardiac pathologies can be compared to verify the applicability of the described method and improve its usability in ambulatorial clinic and other applicability for mobile monitoring.

ABSTRACT Resumo Neste artigo é apresentada a descrição de um ambiente virtual de ensino a distânc... more ABSTRACT Resumo Neste artigo é apresentada a descrição de um ambiente virtual de ensino a distância, com característica modular para diversas funções e atividades, desenvolvido para dar suporte tecnológico aos cursos da UniRede. O ambiente apresentado é de código aberto e gratuito, possibilita a integração entre professores, tutores, suporte e educandos por meio de atividades online, fora de discussões, chat, e-mail, agenda eletrônica e outros.

In this paper authors present a didactic method for teaching Data Structures on Computer Science ... more In this paper authors present a didactic method for teaching Data Structures on Computer Science undergraduate course. An approach using functional along with procedural languages (Haskell and ANSI C) is presented, and adequacy of such a method is discussed. Authors are also concerned on how functional language can help students to learn fundamental concepts and acquire competence on data typing and structure for real programming.

Anais de XXXIII Simpósio Brasileiro de Telecomunicações, 2015

Resumo-O uso de imagens de alta definição tem, via de regra, um custo elevado enquanto o uso de i... more Resumo-O uso de imagens de alta definição tem, via de regra, um custo elevado enquanto o uso de imagens de resolução menor tem custo acessível e necessita de ampliação. Este trabalho apresenta uma metodologia que envolve algumas ferramentas matemáticas aplicadas ao tratamento de imagens, para ampliação de imagens que evite o deslocamento ou a deformação dos pontos em espaços georreferenciados. Neste, propõem-se o estudo de interpolações multivariadas, combinando-se Séries de Fourier e polinômios de Chebyshev para filtragem. Além, da combinação com algoritmos de correção de cor, luminosidade e intensidade, por esses apresentarem resultados que possibilitam o tratamento do problema. Palavras-Chave-Ampliação de imagem, georreferenciamento, Resolução Multiescalonada, superresolução de imagem.

Compression and cryptography of digital data for network transmission using digi tal audio signal... more Compression and cryptography of digital data for network transmission using digi tal audio signals and its wavelet tranforms is described in this paper. Wavelts are mathematical functions which can amplify data intervals, splitting them into different segments off different frequencies. This treatment allows us to perfo rm data analysis and compression on each corresponding scale. A Wavelet transfor m in a space of some specific data function can sparsely represent each subspace of this function in the "time-frequency" domain. This property allows u s to use it for data compression, and once this compression is biorthogonally dependent of the filter coefficients it can be used as a cryptographic tool where those coefficients can represent pairs of public and pr ived keys. In this work we describe a new method to compress and encrypt digital data, simultaneously, for transmission over a network environment. Although results were yelded for digital audio data the method can ...

Compression and cryptography of digital data for network transmission using digi tal audio signal... more Compression and cryptography of digital data for network transmission using digi tal audio signals and its wavelet tranforms is described in this paper. Wavelts are mathematical functions which can amplify data intervals, splitting them into different segments off different frequencies. This treatment allows us to perfo rm data analysis and compression on each corresponding scale. A Wavelet transfor m in a space of some specific data function can sparsely represent each subspace of this function in the "time-frequency" domain. This property allows u s to use it for data compression, and once this compression is biorthogonally dependent of the filter coefficients it can be used as a cryptographic tool where those coefficients can represent pairs of public and pr ived keys. In this work we describe a new method to compress and encrypt digital data, simultaneously, for transmission over a network environment. Although results were yelded for digital audio data the method can ...

ABSTRACT In this paper authors present a didactic method for teaching Data Structures on Computer... more ABSTRACT In this paper authors present a didactic method for teaching Data Structures on Computer Science undergraduate course. An approach using func-tional along with procedural languages (Haskell and ANSI C) is presented, and adequacy of such a method is discussed. Authors are also concerned on how functional language can help students to learn fundamental concepts and acquire competence on data typing and structure for real programming.

Anais do II TecEAD

... Page 6. [5] DIXOT, S. & YE, Y. 2001.“Streamlining the Internet-Fiber Connection”, IEEE Sp... more ... Page 6. [5] DIXOT, S. & YE, Y. 2001.“Streamlining the Internet-Fiber Connection”, IEEE Spectrum, 38 (4), (April), pp.52-57. [6] GILLIGAN,R; THOMSON, S.; BOUND, J. e STEVENS, W. “Basic Socket Interface Extensions for IPv6”, RFC 2133, Apr. 1977. ...

ABSTRACT Using the octave chromatic division (2i/12) and the difference between two tones (22/12 ... more ABSTRACT Using the octave chromatic division (2i/12) and the difference between two tones (22/12 - 21/12 ) we define a! and p in Pollen’s parametric equations to calculate new wavelet coefficients. We first calculate 4 coefficients, using cy = 21/12 and ,8 = 0 and then we use Q = 21/12 and p = 22/12 - 21/12 for definition of 6 coefficients. In this paper, we describe its calculation, and show results yelded in direct and inverse transform of musical signals.

Resumo A s audio-digital tem sido um dos principais objetos de pesquisa na area de processamento ... more Resumo A s audio-digital tem sido um dos principais objetos de pesquisa na area de processamento digital de sinais. In umeros algoritmos de ltros, m etodos de s ann alise e convers~ ao A/D t^ em surgido recentemente. Os soostica-dos circu de processamento de som (placas de som) associados aos velozes processadores e a programas espec softwares espec O Sapphire e um compilador ac ustico desenvolvido por Finnis, implementado por Krzystoo (Linux) e Dovicchi (IBM-AIX) e que se tornou bastante popular. O programa usa um arquivo texto escrito na Linguagem Sapphire Geraa c~ ao de m usica (score) e ger^ encia instrumental; 3) Processamento de sinais, atrav es de ltros em eventos pr e-amostrados. O Sapphire usa o conceito de Ray-Tracing e oferece a possibilidade de inserir sons previamente compilados ou amostrados, nos scripts, utilizando geradores de envelope sonoro, osciladores e ltros digitais. Abstract Digital Audio Synthesis is becoming one of the top research points in the Digital Sign...

International Symposium on Signal Processing and Its Applications, 2005

In this paper, authors present a formal description of the algorithm for the construction of N-pa... more In this paper, authors present a formal description of the algorithm for the construction of N-parametric equations, which provides the attainment of any set of dilation coefficients from a set of N angles that sum /2. These coefficients can be used to construct any dimensional Wavelet filter bank to be applied to analysis and reconstruction of specific signal data.

This paper presents the description of a formal mathematical and computing method of Discrete Wav... more This paper presents the description of a formal mathematical and computing method of Discrete Wavelet Trans-form (DWT) combined with auto-correlation power spectrum. Detail segments (high-pass) of the first and second scale level of DWT ("lifting scheme") are convoluted using auto-correlation to achieve a more precise identification of cardiopathies which can be detected and represented for automated analysis due to power spectra differences. This study shows how ECG signals of normal and some cardiac pathologies can be compared to verify the applicability of the described method and improve its usability in ambulatorial clinic and other applicability for mobile monitoring.

ABSTRACT Resumo Neste artigo é apresentada a descrição de um ambiente virtual de ensino a distânc... more ABSTRACT Resumo Neste artigo é apresentada a descrição de um ambiente virtual de ensino a distância, com característica modular para diversas funções e atividades, desenvolvido para dar suporte tecnológico aos cursos da UniRede. O ambiente apresentado é de código aberto e gratuito, possibilita a integração entre professores, tutores, suporte e educandos por meio de atividades online, fora de discussões, chat, e-mail, agenda eletrônica e outros.