Remote Sensing of Aboveground Biomass in Tropical Secondary Forests: A Review

Tropical landscapes are, in general, a mosaic of pasture, agriculture, and forest undergoing various stages of succession. Forest succession is comprised of continuous structural changes over time and results in increases in aboveground biomass (AGB). New remote sensing methods, including sensors, image processing, statistical methods, and uncertainty evaluations, are constantly being developed to estimate biophysical forest changes. We review 318 peer-reviewed studies related to the use of remotely sensed AGB estimations in tropical forest succession studies and summarize their geographic distribution, sensors and methods used, and their most frequent ecological inferences. Remotely sensed AGB is broadly used in forest management studies, conservation status evaluations, carbon source and sink investigations, and for studies of the relationships between environmental conditions and forest structure. Uncertainties in AGB estimations were found to be heterogeneous with biases related to sensor type, processing methodology, ground truthing availability, and forest characteristics. Remotely sensed AGB of successional forests is more reliable for the study of spatial patterns of forest succession and over large time scales than that of individual stands. Remote sensing of temporal patterns in biomass requires further study, in particular, as it is critical for understanding forest regrowth at scales useful for regional or global analyses

Coupling finite elements for modelling fluid flow in fractured porous media

The presence of discontinuities such as cracks and faults in porous media can remarkably affect the fluid pressure distribution. This is due to considerable contrast between hydraulic properties of porous matrix and discontinuity. Several numerical techniques have been adopted to simulate the behaviour of fractured porous media subjected to fluid flow mostly in the context of discrete fracture- matrix models. Current approaches still have several shortcomings, namely in terms of computational costs from large number of additional degrees of freedom to capture the discontinuities, and the implementation of special integration procedures. The present work proposes a new technique to model fluid flow in saturated fractured porous media based on coupling finite elements to enable embedding the preferential paths of flow created by discontinuities in regular meshes. The discretisation of fracture and porous medium does not need to conform and the meshes are coupled without additional degrees of freedom. Two numerical examples are presented to assess the performance of the new method in comparison with other techniques available in the literature.ARC DE150101703, ARC DP170104192, ARC LP14010059

Situação atual e demandas de pesquisa, desenvolvimento e inovação tecnológica em forrageiras e pastagens - Região Sul do Rio Grande do Sul.

bitstream/item/33620/1/documento-178.pd

The Screen representation of spin networks. Images of 6j symbols and semiclassical features

This article presents and discusses in detail the results of extensive exact calculations of the most basic ingredients of spin networks, the Racah coefficients (or Wigner 6j symbols), exhibiting their salient features when considered as a function of two variables - a natural choice due to their origin as elements of a square orthogonal matrix - and illustrated by use of a projection on a square "screen" introduced recently. On these screens, shown are images which provide a systematic classification of features previously introduced to represent the caustic and ridge curves (which delimit the boundaries between oscillatory and evanescent behaviour according to the asymptotic analysis of semiclassical approaches). Particular relevance is given to the surprising role of the intriguing symmetries discovered long ago by Regge and recently revisited; from their use, together with other newly discovered properties and in conjunction with the traditional combinatorial ones, a picture emerges of the amplitudes and phases of these discrete wavefunctions, of interest in wide areas as building blocks of basic and applied quantum mechanics.Comment: 16 pages, 13 figures, presented at ICCSA 2013 13th International Conference on Computational Science and Applicatio

The Screen representation of spin networks: 2D recurrence, eigenvalue equation for 6j symbols, geometric interpretation and Hamiltonian dynamics

This paper treats 6j symbols or their orthonormal forms as a function of two variables spanning a square manifold which we call the "screen". We show that this approach gives important and interesting insight. This two dimensional perspective provides the most natural extension to exhibit the role of these discrete functions as matrix elements that appear at the very foundation of the modern theory of classical discrete orthogonal polynomials. Here we present 2D and 1D recursion relations that are useful for the direct computation of the orthonormal 6j, which we name U. We present a convention for the order of the arguments of the 6j that is based on their classical and Regge symmetries, and a detailed investigation of new geometrical aspects of the 6j symbols. Specifically we compare the geometric recursion analysis of Schulten and Gordon with the methods of this paper. The 1D recursion relation, written as a matrix diagonalization problem, permits an interpretation as a discrete Schr\"odinger-like equations and an asymptotic analysis illustrates semiclassical and classical limits in terms of Hamiltonian evolution.Comment: 14 pages,9 figures, presented at ICCSA 2013 13th International Conference on Computational Science and Applicatio

DOCENTES DE UM CURSO DE LICENCIATURA PLENA EM MATEMÁTICA: COMO ELES FALAM DE SUAS PEDAGOGIAS UNIVERSITÁRIAS

Neste artigo, refletimos sobre parte de nossa pesquisa de doutorado concluídoem janeiro de 2014. O objetivo foi analisar o que disseram os docentes de ensino superior sobre suas pedagogias universitárias e o significado de “ser professor em um curso de licenciatura plena em Matemática”. No recorte feito para este artigo, utilizamos os dados coletados por meio do levantamento bibliográfico e das entrevistas semiestruturadas realizadas com 16 docentes universitários do curso de licenciatura plena em Matemática da Unemat, Campus Universitário de Cáceres. Usamos a análise de conteúdo como procedimento na apreciação dos dados. Nesta pesquisa, mostrou-se que a Pedagogia Universitária (PU) é uma temática pouco presente e explorada nas discussões e práticas dos professores formadores dessa licenciatura. Quando discorrem sobre PU, não usam conceitos alusivos ela, e, sim, à formação de professores na área que atuam, ao ensino universitário, aos estudantes da licenciatura em Matemática, ao quadro docente desse curso e às ações deles, à formação para serem professores formadores da licenciatura, à formação pedagógica necessária para os estudantes que serão futuros professores, dentre outros assuntos. O significado de ser professor formador em uma licenciatura é de grande responsabilidade na formação de novos professores. Essa responsabilidade requer formação continuada que os auxilie, que estabeleça o diálogo reflexivo entre os professores, que promova a troca de experiências e a colaboração como princípio para incrementar a pedagogia universitária desses docentes

Stem cell transplantation in 40 pts with Fanconi anemia (FA): Excellent survival and low toxicity for pts with a related HLA identical donor

Univ Fed Parana, BR-80060000 Curitiba, Parana, BrazilEPM, Inst Oncol Pediat, São Paulo, BrazilEPM, Inst Oncol Pediat, São Paulo, BrazilWeb of Scienc

The screen representation of vector coupling coefficients or Wigner 3j symbols: exact computation and illustration of the asymptotic behavior

The Wigner $3j$ symbols of the quantum angular momentum theory are related to the vector coupling or Clebsch-Gordan coefficients and to the Hahn and dual Hahn polynomials of the discrete orthogonal hyperspherical family, of use in discretization approximations. We point out the important role of the Regge symmetries for defining the screen where images of the coefficients are projected, and for discussing their asymptotic properties and semiclassical behavior. Recursion relationships are formulated as eigenvalue equations, and exploited both for computational purposes and for physical interpretations.Comment: 14 pages, 8 figures, presented at ICCSA 2014, 14th International Conference on Computational Science and Application