Surface tension implementation for Gensmac 2D

In the present work we describe a method which allows the incorporation of surface tension into the GENSMAC2D code. This is achieved on two scales. First on the scale of a cell, the surface tension effects are incorporated into the free surface boundary conditions through the computation of the capillary pressure. The required curvature is estimated by fitting a least square circle to the free surface using the tracking particles in the cell and in its close neighbors. On a sub-cell scale, short wavelength perturbations are filtered out using a local 4-point stencil which is mass conservative. An efficient implementation is obtained through a dual representation of the cell data, using both a matrix representation, for ease at identifying neighbouring cells, and also a tree data structure, which permits the representation of specific groups of cells with additional information pertaining to that group. The resulting code is shown to be robust, and to produce accurate results when compared with exact solutions of selected fluid dynamic problems involving surface tension

A three-step approach to post-fire mortality modelling in maritime pine (Pinus pinaster Ait.) stands for enhanced forest planning in Portugal

Maritime pine (Pinus pinaster Ait) is a very important timber-producing species in Portugal with a yield of ~67.1 million m3 year21. It covers ~22.6 per cent of the forest area (710.6 × 103 ha). Fire is the most significant threat to maritime pine plantations. This paper discusses research aiming at the development of post-fire mortality models for P. pinaster Ait stands in Portugal that can be used for enhanced integration of forest and fire management planning activities. Post-fire mortality was modelled using biometric and fire data from 2005/2006 National Forest Inventory plots and other sample plots within 2006–2008 fire perimeters. A three-step modelling strategy based on logistic regression methods was used. Firstly, the probability of mortality to occur after a wildfire in a stand is predicted and secondly, the degree of mortality caused by a wildfire on stands where mortality occurs is quantified. Thirdly, mortality is distributed among trees. The models are based on easily measurable tree characteristics so that forest managers may predict post-fire mortality based on forest structure. The models show that relative mortality decreases when average d.b.h. increases, while slope and tree size diversity increase the mortalityinfo:eu-repo/semantics/publishedVersio

Bone lengthening by physial distraction. An experimental study.

Experimental physial distraction was carried out in the distal part of the femur in 45 two-month old lambs in order to study the basic mechanisms of lengthening as well as the viability of the growth cartilage after using this method. The animals were divided into three groups (A, B and C), and each group into three subgroups (1, 2 and 3) according to the rate of distraction used (2 mm/day, 1 mm/day, 0.5 mm/day) and the time of sacrifice. The results obtained show that the basic lengthening mechanisms consists, firstly, in the production of a fracture between the metaphysis and the epiphysis and, secondly, that the lower the distraction speed employed, the greater is the short-term and long-term viability of the growth cartilage. Optimum viability was observed at a distraction rate of 0.5 mm/day. On this basis we conclude that in clinical practice physical distraction could be indicated for children at an early stage of skeletal growth and repeated later provided that the rate of distraction is kept within reasonable limits

Sistema de gestão ambiental - uma proposta corporativa para a Embrapa.

Histórico e contextualização; Estratégia de Ação para Implantação de um Sistema de Gestão Ambiental Corporativo; Objetivos Gerais e Específicos do Sistema de Gestão Ambiental Corporativo; Apresentação do Sistema de Gestão Ambiental Corporativo neste Documento