27 citations · 229 across the 64 of their papers we have counts for
66 papers
Privatization of Probability Distributions by the Wavelet Integral approach
Helio M. de Oliveira, Raydonal Ospina, Victor Leiva +2
A naive theory of additive perturbations on a continuous probability distribution is presented. We propose a new privatization mechanism based on a naive theory of a perturbation o…
Geometrical Representation for Number-theoretic Transforms
H. M. de Oliveira, R. J. Cintra
This short note introduces a geometric representation for binary (or ternary) sequences. The proposed representation is linked to multivariate data plotting according to the radar…
Rounded Hartley Transform: A Quasi-involution
R. J. Cintra, H. M. de Oliveira, C. O. Cintra
A new multiplication-free transform derived from DHT is introduced: the RHT. Investigations on the properties of the RHT led us to the concept of weak-inversion. Using new construc…
Infinite Sequences, Series Convergence and the Discrete Time Fourier Transform over Finite Fields
R. M. Campello de Souza, M. M. Campello de Souza, H. M. de Oliveira +1
Digital Transforms have important applications on subjects such as channel coding, cryptography and digital signal processing. In this paper, two Fourier Transforms are considered,…
Multidimensional Wavelets for Scalable Image Decomposition: Orbital Wavelets
H. M. de Oliveira, V. V. Vermehren, R. J. Cintra
Wavelets are closely related to the Schrödinger's wave functions and the interpretation of Born. Similarly to the appearance of atomic orbital, it is proposed to combine anti-symme…
An Overview of Self-Similar Traffic: Its Implications in the Network Design
Ernande F. Melo, H. M. de Oliveira
The knowledge about the true nature of the traffic in computer networking is a key requirement in the design of such networks. The phenomenon of self-similarity is a characteristic…
ND-Wavelets Derived from Anti-symmetric Systems of Isolated Particles using the Determinant of Slater
H. M. de Oliveira, V. V. Vermehren
Wavelets are known to be closely related to atomic orbital. A new approach of 2D, 3D and multidimensional wavelet system is proposed from a paralell with anti-symmetric systems of…
A Note on the Shannon Entropy of Short Sequences
H. M. de Oliveira, Raydonal Ospina
For source sequences of length L symbols we proposed to use a more realistic value to the usual benchmark of number of code letters by source letters. Our idea is based on a quanti…
von Mises Tapering: A Circular Data Windowing
H. M. de Oliveira, F. Chaves
Continuous standard windowing is revisited and a new taper shape is introduced, which is based on the normal circular distribution by von Mises. Continuous-time windows are conside…
The Hamming and Golay Number-Theoretic Transforms
A. J. A. Paschoal, R. M. Campello de Souza, H. M. de Oliveira
New number-theoretic transforms are derived from known linear block codes over finite fields. In particular, two new such transforms are built from perfect codes, namely the \texti…
A Kotel'nikov Representation for Wavelets
H. M. de Oliveira, R. J. Cintra, R. C. de Oliveira
This paper presents a wavelet representation using baseband signals, by exploiting Kotel'nikov results. Details of how to obtain the processes of envelope and phase at low frequenc…
Linear Computer-Music through Sequences over Galois Fields
H. M. de Oliveira, R. C. de Oliveira
It is shown how binary sequences can be associated with automatic composition of monophonic pieces. We are concerned with the composition of e-music from finite field structures. T…
Understanding MIDI: A Painless Tutorial on Midi Format
H. M. de Oliveira, R. C. de Oliveira
A short overview demystifying the midi audio format is presented. The goal is to explain the file structure and how the instructions are used to produce a music signal, both in the…
Multiuser Communication Based on the DFT Eigenstructure
R. M. Campello de Souza, H. M. de Oliveira, R. J. Cintra
The eigenstructure of the discrete Fourier transform (DFT) is examined and new systematic procedures to generate eigenvectors of the unitary DFT are proposed. DFT eigenvectors are…
Performance Assessment of WhatsApp and IMO on Android Operating System (Lollipop and KitKat) during VoIP calls using 3G or WiFi
R. C. de Oliveira, H. M. de Oliveira, R. A. Ramalho +1
This paper assesses the performance of mobile messaging and VoIP connections. We investigate the CPU usage of WhatsApp and IMO under different scenarios. This analysis also enabled…
A New Information Theoretical Concept: Information-Weighted Heavy-tailed Distributions
H. M. de Oliveira, R. J. Cintra
Given an arbitrary continuous probability density function, it is introduced a conjugated probability density, which is defined through the Shannon information associated with its…
Efficient Multiplex for Band-Limited Channels: Galois-Field Division Multiple Access
H. M. de Oliveira, R. M. Campello de Souza, A. N. Kauffman
A new Efficient-bandwidth code-division-multiple-access (CDMA) for band-limited channels is introduced which is based on finite field transforms. A multilevel code division multipl…
A Short Survey on Arithmetic Transforms and the Arithmetic Hartley Transform
R. J. Cintra, H. M. de Oliveira
Arithmetic complexity has a main role in the performance of algorithms for spectrum evaluation. Arithmetic transform theory offers a method for computing trigonometrical transforms…
Wavelets for Elliptical Waveguide Problems
M. M. S. Lira, H. M. de Oliveira, R. J. Cintra +1
New elliptic cylindrical wavelets are introduced, which exploit the relationship between analysing filters and Floquet's solution of Mathieu differential equations. It is shown tha…
Application of Enhanced-2D-CWT in Topographic Images for Mapping Landslide Risk Areas
V. V. Vermehren Valenzuela, R. D. Lins, H. M. de Oliveira
There has been lately a number of catastrophic events of landslides and mudslides in the mountainous region of Rio de Janeiro, Brazil. Those were caused by intense rain in localiti…
Shannon and Renyi Entropy of Wavelets
H. M. de Oliveira
This paper reports a new reading for wavelets, which is based on the classical 'De Broglie' principle. The wave-particle duality principle is adapted to wavelets. Every continuous…
Huygens Wave Equations in the Field of 2D-CWT
V. V. Vermehren, H. M. de Oliveira
In this paper it is shown the performing of an optical transform to state the scalar diffraction in the formulation of the wavelet transform and the 'wave equations'. From there, a…
Quantum Decoding with Venn Diagrams
C. M. F. Barros, Francisco Marcos de Assis, H. M. de Oliveira
The quantum error correction theory is as a rule formulated in a rather convoluted way, in comparison to classical algebraic theory. This work revisits the error correction in a no…
Radix-2 Fast Hartley Transform Revisited
H. M. de Oliveira, V. L. Sousa, H. A. N. +1
A Fast algorithm for the Discrete Hartley Transform (DHT) is presented, which resembles radix-2 fast Fourier Transform (FFT). Although fast DHTs are already known, this new approac…