Now showing items 131-140 of 140
On the standardization of the fishing effort
(Acta Amazonica, 2000-03-01) [Artigo]
In this note we demonstrate that the use of an index to standardize the fishing effort using the cpue of a standard vessel or gear is mistaken, once the cpues- catch per unit of total effort after standardization is similar ...
Lattices from maximal orders into quaternion algebras
(Journal Of Pure And Applied Algebra, 2015-04-01) [Artigo]
We propose an algebraic framework to construct dense lattices from maximal orders of a quaternion algebra whose center is an imaginary quadratic field. This work extends  where a method called algebraic reduction has ...
Resonance capture at arbitrary inclination
(Monthly Notices Of The Royal Astronomical Society, 2015-01-11) [Artigo]
Resonance capture is studied numerically in the three-body problem for arbitrary inclinations. Massless particles are set to drift from outside the 1: 5 resonance with a Jupiter-mass planet thereby encountering the web of ...
Cobordism of maps of locally orientable Witt spaces
(Publicationes Mathematicae-debrecen, 2019-01-01) [Artigo]
The aim of this work is to present some remarks on cobordism of normally nonsingular maps between compact locally orientable Witt spaces. By using the Wu classes defined by Goresky and Pardon, we give a definition of ...
Some results on extension of maps and applications
(Proceedings of the Royal Society of Edinburgh Section A: Mathematics, 2019-01-01) [Artigo]
This paper concerns extension of maps using obstruction theory under a non-classical viewpoint. It is given a classification of homotopy classes of maps and as an application it is presented a simple proof of a theorem by ...
Existence and uniqueness of solution for abstract differential equations with state-dependent delayed impulses
(Journal Of Fixed Point Theory And Applications, 2019-03-01) [Artigo]
We study the existence and uniqueness of mild and classical solutions for a general class of abstract impulsive differential equations with state-dependent impulses. Some examples on partial differential equations are presented.
Letters from foreign mathematicians about the context of Brazil in the 1970'sCartas de Matemáticos Estrangeiros sobre o Contexto Brasileiro no Início da Década de 1970
(Bolema - Mathematics Education Bulletin, 2019-01-01) [Artigo]
The International Symposium on Dynamical Systems was held in Salvador, in 1971, with the participation of important Brazilian and foreign mathematicians. Steve Smale, distinguished mathematician and winner of the Fields ...
Multimedia Retrieval Through Unsupervised Hypergraph-Based Manifold Ranking
(Ieee Transactions On Image Processing, 2019-12-01) [Artigo]
Accurately ranking images and multimedia objects are of paramount relevance in many retrieval and learning tasks. Manifold learning methods have been investigated for ranking mainly due to their capacity of taking into ...
The (reasonable) effectiveness of mathematics in empirical science
(Disputatio-philosophical Research Bulletin, 2018-12-01) [Artigo]
I discuss here the pragmatic problem in the philosophy of mathematics, that is, the applicability of mathematics, particularly in empirical science, in its many variants. My point of depart is that all sciences are formal, ...
Can Drag Force Suppress Fermi Acceleration in a Bouncer Model?
(Mathematical Problems in Engineering, 2009-01-01) [Artigo]
Some dynamical properties for a bouncer model-a classical particle of mass m falling in the presence of a constant gravitational field g and hitting elastically a periodically moving wall-in the presence of drag force that ...