Parallelization of the SUFI2 algorithm: a Windows HPC approach.

The Soil and Water Assessment Tool (SWAT) has been used for evaluating land use changes on water resources worldwide, and like many models, SWAT requires calibration. However, the execution time of these calibrations can be rather long, reducing the time available for proper analysis. This paper presents a Windows approach for calibrating SWAT using a multinodal cluster computer, composed of six computers with i7 processors (3.2 GHz; 12 cores), 8 GB RAM and 1 TB HDD each. The only requirement for this type of cluster is to have 64-bit processors. Our computers were setup with Windows Server HPC 2012 R2, a network switch 10/100, and regular Ethernet cables. We used the SUFI2 algorithm that comes with SWAT-CUP package to perform calibrations with 100 simulations at node level. Calibration runs were configured as follows: 1-12 (1 process interval), and 12-72 (12 processes interval), resulting in 17 runs. Each run was repeated three times, and results are presented as the mean execution time, in order to minimize any influence of resources fluctuations. Results showed that time of execution was reduced by almost half by using nine processes (15 min) in comparison with the one node control (28 min). We observed a linear decrease of execution time from one to nine processes. With additional processes, execution time increased about 23% and stabilized at 80% of the control. All processing is divided into five steps: distribute files (2.24% of all processing time), organize samples (0.89%), run SWAT (47.59%), collect results (46.51%) and cleanup (0.28%)

Direct evaluation of mixed mode i+ii cohesive laws of wood by coupling mmb test with dic

grant number FCOMP-01-0124-287 FEDER-022692Governing cohesive laws in mixed mode I+II loading of Pinus pinaster Ait. are directly identified by coupling the mixed mode bending test with full-field displacements measured at the crack tip by Digital Image Correlation (DIC). A sequence of mixed mode ratios is studied. The proposed data reduction relies on: (i) the compliance-based beam method for evaluating strain energy release rate; (ii) the local measurement of displacements to compute the crack tip opening displacement; and (iii) an uncoupled approach for the reconstruction of the cohesive laws and its mode I and mode II components. Quantitative parameters are extracted from the set of cohesive laws components in function of the global phase angle. Linear functions were adjusted to reflect the observed trends and the pure modes (I and II) fracture parameters were estimated by extrapolation. Results show that the obtained assessments agree with previous experimental measurements addressing pure modes (I and II) loadings on this wood species, which reveals the appropriateness of the proposed methodology to evaluate the cohesive law under mixed mode loading and its components.publishersversionpublishe

Tendência da temperatura máxima, média e mínima no município de Juazeiro, no período de 1966 a 2005.

Esse é o objetivo deste trabalho, que realizou análise das tendências já detectáveis da temperatura do ar máxima, média e mínima mensal no município de Juazeiro ? BA, no período de 1966 a 2005, com base nos dados coletados na estação meteorológica da Fazenda Experimental de Mandacaru, em Juazeiro - BA, localizada à latitude, 09º 24? Sul, longitude, 40º 26? Oeste e altitude 375m

Bit-Vector Model Counting using Statistical Estimation

Approximate model counting for bit-vector SMT formulas (generalizing \#SAT) has many applications such as probabilistic inference and quantitative information-flow security, but it is computationally difficult. Adding random parity constraints (XOR streamlining) and then checking satisfiability is an effective approximation technique, but it requires a prior hypothesis about the model count to produce useful results. We propose an approach inspired by statistical estimation to continually refine a probabilistic estimate of the model count for a formula, so that each XOR-streamlined query yields as much information as possible. We implement this approach, with an approximate probability model, as a wrapper around an off-the-shelf SMT solver or SAT solver. Experimental results show that the implementation is faster than the most similar previous approaches which used simpler refinement strategies. The technique also lets us model count formulas over floating-point constraints, which we demonstrate with an application to a vulnerability in differential privacy mechanisms

Desempenho de linhagens de feijão-caupi com grãos de tegumento branco rugoso extra grandes sob cultivo irrigado.

Este trabalho teve por objetivo verificar o desempenho produtivo de 19 genótipos de feijão-caupi em cultivo irrigado nas condições edafoclimatológicas de Teresina-PI. O experimento foi conduzido sob irrigação por aspersão convencional, na Embrapa Meio-Norte, em Teresina, Piauí, nos anos 2008/2009. Foram realizados três ensaios utilizando-se delineamento de blocos casualizados com quatro repetições e 19 tratamentos, onde avaliou-se a produtividade de grãos. Utilizou-se a análise de variância univariada para aferir as respostas dos genótipos aos diferentes ambientes de cultivo e o teste Scott-Knott para comparação das médias. Foi observada resposta diferenciada dos genótipos nos ambientes. Na análise conjunta foi detectada diferença entre ambientes e a interação genótipo x ambiente foi significativa. Os melhores genótipos foram MNC05-828C-1-11, BRS Novaera, MNC05-829C-1-8 e MNC05-828C-30-11, todos com produtividade média superior a 1.400 kg.ha-1, podendo chegar 1.800 kg.ha-1. O melhor ambiente foi Teresina 2009 com produtividade de grãos média de 1.572,59 kg.ha-1.CONAC 2012. Disponível em: http://www.conac2012.org/resumos/pdf/182b.pdf. Acesso em: 05 ago. 2013

Buckling Thin Disks and Ribbons with Non-Euclidean Metrics

I consider the problem of a thin membrane on which a metric has been prescribed, for example by lithographically controlling the local swelling properties of a polymer thin film. While any amount of swelling can be accommodated locally, geometry prohibits the existence of a global strain-free configuration. To study this geometrical frustration, I introduce a perturbative approach. I compute the optimal shape of an annular, thin ribbon as a function of its width. The topological constraint of closing the ribbon determines a relationship between the mean curvature and number of wrinkles that prevents a complete relaxation of the compression strain induced by swelling and buckles the ribbon out of the plane. These results are then applied to thin, buckled disks, where the expansion works surprisingly well. I identify a critical radius above which the disk in-plane strain cannot be relaxed completely.Comment: 6 pages, 5 figures; lengthened to clarify previously confusing issues. To appear in EP

Avaliação espaço-temporal do balanço hídrico no estado de Pernambuco.

O projeto ora apresentado, tem como objetivo analisar espaço-temporalmente a dinâmica hídrica do estado do Pernambuco

Uso de índices RGB para o Bioma Caatinga associados a dados meteorológicos e índices de vegetação: estudos iniciais.

O presente estudo teve como objetivo monitorar a cobertura vegetal em uma área de Caatinga preservada por meio de imagens digitais, bem como sua correlação com dados meteorológicos e índices de vegetação obtidos em imagens MODIS

Estimativa espaço-temporal do balanço de carbono em áreas de Caatinga no município de Petrolina, Brasil.

Muito tem sido discutido sobre mudança climática, gases de efeito estufa, global aquecimento e seus possíveis efeitos nas esferas nacionais e internacionais. As atividades humanas têm sido apontadas com uma das maiores causas das mudanças climáticas pelo aumento na concentração de CO2 atmosférico e outros gases do efeito estufa