Produção Científica



Artigo em Revista
09/10/2010

SS-traveltime parameters from PP and PS reflections.
The SS-wave traveltimes can be derived from PP- and PS-wave data with the previously derived method. We have extended this method as follows. (1) The previous requirement that sources and receivers be located on a common acquisition surface is removed, which makes the method directly applicable to PS-waves recorded on the ocean bottom and PP-waves recorded at the ocean surface. (2) By using the concept and properties of surface-to-surface propagator matrices, the second-order traveltime derivatives of the SS-waves are obtained. In the same way as for the original method, the proposed extension is valid for arbitrary anisotropic media. The propagator matrix and geometric spreading of an SS-wave reflected at a given point on a target reflector are obtained explicitly from the propagators of the PP- and PS-waves reflected at the same point. These additional parameters provided by the extended method can be used for a partial reconstruction of the SS-wave amplitude as well as for tomographic estimation of the elastic velocity model. A full simulation of the SS-wave, which includes reflection and transmission coefficients, cannot be obtained directly from recorded PP- and PS-wave amplitudes.
Artigo em Revista
09/10/2010

A new stabilized least-squares imaging condition.
The classical deconvolution imaging condition consists of dividing the upgoing wave field by the downgoing wave field and summing over all frequencies and sources. The least-squares imaging condition consists of summing the cross-correlation of the upgoing and downgoing wave fields over all frequencies and sources, and dividing the result by the total energy of the downgoing wave field. This procedure is more stable than using the classical imaging condition, but it still requires stabilization in zones where the energy of the downgoing wave field is small. To stabilize the least-squares imaging condition, the energy of the downgoing wave field is replaced by its average value computed in a horizontal plane in poorly illuminated regions. Applications to the Marmousi and Sigsbee2A data sets show that the stabilized least-squares imaging condition produces better images than the least-squares and cross-correlation imaging conditions.
Material Didático
09/10/2010

Carlos Alberto Dias - A saga da Geofísica Aplicada e da Engenharia de E&P do Petróleo no Brasil.
Fernando S. de Moraes (Org.); Lima, O. A. L. de (Org.); Jessé C. Costa (Org.); Francisco Nepomuceno Filho (Org.). 1. ed. Salvador: Editora da Universidade Federal da Bahia, 2009. v. 1. 265 p.
Material Didático
09/10/2010

Cálculo Numérico.
Marcelo Gomes Pereira ; Roberto Hugo Bielschowsky. 1. ed. Natal: SEDIS - EDUFRN, 2009. v. 01. 300 p.
Material Didático
09/10/2010

Conceitos de Geofísica.
A.F. do Nascimento, F.H.R. Bezerra, W.E. Medeiros, 2010. Natal: Editora EDUFRN. (Livro texto para a disciplina Conceitos de Geofísica do Curso de Física à distancia da UFRN.)
Apresentação
09/10/2010

The use of discrete wavelet transform in road loads signals.
ANDRADE, G. S.; DUARTE, A. A.; SCHNITMAN, L.. In: CONGRESSO SAE BRASIL, 2009, São Paulo. Anais do Congresso SAE Brasil 2009, 2009.
Apresentação
09/10/2010

Aplicação de Redes Neurais Artificiais no Reconhecimento de Padrões de Cartas Dinamométricas de Sistemas de Bombeio Mecânico de Petróleo.
BEZERRA, Marco A.D.; BARRETO FILHO, Manoel de A.; SCHNITMAN, L.. In: IX Simpósio Brasileiro de Automação Inteligente, 2009, Brasília. Anais do IX Simpósio Brasileiro de Automação Inteligente, 2009. v. 9.
Apresentação
09/10/2010

Alternative concepts for the high precision bearings in torque standard machines.
BITENCOURT, Antônio Carlos Peixoto; THESKA, R.; Wagner, A.; LEPIKSON, H. A.; WEINGAERTNER, W.. In: 10th Int Conf of the European Society for Precision Engineering & Nanotechnology, 2010, Delft. Proceedings of 10th Int Conf of the European Society for Precision Engineering & Nanotechnology. Cranfield, England : Euspen - European Society for Precision Engineering & Nanotechnology, 2010. v. 1. p. 474-477.
Apresentação
09/10/2010

UM SISTEMA CAM PARÁ MÁQUINAS DE PROTOTIPAGEM RÁPIDA DE BAIXO CUSTO.
MARTINS, S.R.M.; LEPIKSON, H. A.; COSTA, B.L.S.. In: VI CONEM - Congresso Nacional de Engenharia Mecânica, 2010, Campina Grande, PB. Anais do VI CONEM - Congresso Nacional de Engenharia Mecânica. Rio de Janeiro, RJ : ABCM - Associação Brasileira de Ciências e Engenharia Mecânica, 2010. v. 1. p. 1-9.
Apresentação
09/10/2010

Um estudo sobre a cadeia de rastreabilidade das medições de torque.
NOGUEIRA, Tarso Barretto Rodrigues; LEPIKSON, H. A.; MASCARENHAS, L.A.B.. In: VI CONEM - Congresso Nacional de Engenharia Mecânica, 2010, Campina Grande, PB. Anais do VI CONEM - Congresso Nacional de Engenharia Mecânica. Rio de Janeiro, RJ : ABCM - Associação Brasileira de Ciências e Engenharia Mecânica, 2010. v. 1. p. 1-10.
<<  <   1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32   >  >>