Validation of three new measure-correlate-predict models for the long-term prospection of the wind resource

The estimation of the long-term wind resource at a prospective site based on a relatively short on-site measurement campaign is an indispensable task in the development of a commercial wind farm. The typical industry approach is based on the measure-correlate-predict �MCP� method where a relational model between the site wind velocity data and the data obtained from a suitable reference site is built from concurrent records. In a subsequent step, a long-term prediction for the prospective site is obtained from a combination of the relational model and the historic reference data. In the present paper, a systematic study is presented where three new MCP models, together with two published reference models �a simple linear regression and the variance ratio method�, have been evaluated based on concurrent synthetic wind speed time series for two sites, simulating the prospective and the reference site. The synthetic method has the advantage of generating time series with the desired statistical properties, including Weibull scale and shape factors, required to evaluate the five methods under all plausible conditions. In this work, first a systematic discussion of the statistical fundamentals behind MCP methods is provided and three new models, one based on a nonlinear regression and two �termed kernel methods� derived from the use of conditional probability density functions, are proposed. All models are evaluated by using five metrics under a wide range of values of the correlation coefficient, the Weibull scale, and the Weibull shape factor. Only one of all models, a kernel method based on bivariate Weibull probability functions, is capable of accurately predicting all performance metrics studied.

Morphometry of megakaryocytes in the liver of New Zealand White rabbits during intrauterine and postnatal development

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphology of alumina: a comparison between infrared spectroscopy and X-ray diffractometry

Morphology of three samples of alumina are investigated. Infrared spectra are analysed by use of their morphology through the theory of average dielectric constant. Crystal shape is obtained from X-ray diffraction patterns by reflection intensity ratio. In the case of electron scanning microscopy, shape factor was obtained by an average axial ratio of the particles. Comparison of results show that there is agreement among these techniques and infrared spectra can be used to determine the morphology of alumina particles from 2.7 to 10 mu m, even for heterogeneous samples. (C) 1999 Elsevier B.V. B.V. All rights reserved.

Histology and morphometry of the testes of adult domestic cats (Felis catus)

Testicles of 30 mongrel cats were analyzed histologically and morphometrically, divided into three groups: G1 (1-2 years old), G2 (over 2 and up to 4 years old) and G3 (over 4 and up to 6 years old). After orchiectomy and histopathology, the morphometric parameters studied were: thickness of the tunica albuginea (72 mu m) and seminiferous epithelium (77.19 mu m), perimeter (53.81; 90.57 mu m), (54.80; 101.07 mu m); area (174.23; 494.55 mu m(2)), (176.68; 629.70 mu m(2)); maximum diameter (14.94; 28.02 mu m), (14.76; 31.66 mu m); minimum diameter (13.25; 21.92 mu m), (13.30; 24.52 mu m); and shape factor (index for regularity of the format) (1.36; 1.36), (1.39; 1.35) of the nucleus and cytoplasm of spermatogonia and Leydig cells, respectively. The results can be used for comparative studies and contribute knowledge concerning the height of the seminiferous epithelium, thickness of the tunica albuginea and size of spermatogonia and Leydig cells.

Análise dos parâmetros morfométricos da bacia do Rio Preto, Serra do Espinhaço (Minas Gerais, Brasil)

The Rio Preto Hydrographic Basin (RPHB) is located in the North-central portion of the state of Minas Gerais, Brazil, 30 km ENE of the city of Diamantina. The sources of the stream of that name are found in the Rio Preto State Park, which has an area of 10,755 hectares. The total area, perimeter, extension, and axial length of the RPHB, as well as other morphometric characteristics, with emphasis on shape indexes, were obtained with the help of the ArcGis 9.2 program. The cartographic data were taken from digitalized topographic charts in a scale of 1:100,000 of the Brazilian Geographical Institute (IBGE). The measured drainage area is of 389.3 km2 and the perimeter is 136.9 km. Due to structural influence, the shape of the RPHB is irrgular and elongated, with drainage developed in a dendritic and parallel pattern. Those characteristics were checked by means of the compaxity coefficient and the shape factor. The first one was estimated in 1.94, what implies that the basin is not subject to fast flooding in years with normal precipitation. The high degree of fluvial downcutting of the basin is confirmed by the fact that it is a 5th order basin, it presents a significant branching rate and a medium drainage density.

Control of flexural waves on a beam using distributed vibration neutralisers

This paper is concerned with the use of distributed vibration neutralisers to control the transmission of flexural waves on a beam. Of particular interest is an array of beam-like neutralisers and a continuous plate-like neutraliser. General expressions for wave transmission and reflection metrics either side of the distributed neutralisers are derived. Based on transmission efficiency, the characteristics of multiple neutralisers are investigated in terms of the minimum transmission efficiency, the normalised bandwidth and the shape factor, allowing optimisation of their performance. Analytical results show that the band-stop property of the neutraliser array depends on various factors, including the neutraliser damping, mass, separation distance in the array and the moment arm of each neutraliser. Moreover, it is found that the particular attachment configuration of an uncoupled forcemoment-type neutraliser can be used to improve their overall performance. It is also shown that in the limit of many neutralisers in the array, the performance tends to that of a continuous neutraliser. © 2011 Elsevier Ltd.

Avaliação morfométrica dos hepatócitos de ratos diabéticos tratados com neem (azadirachta indica a. juss) e estreptozootocina 6 ch

The effects of extracts from Azadirachta indica A. Juss and streptozotocin, in extreme high dilutions in dinamized systems, on hepatocyte morphometry of rats with diabetes mellitus induced by streptozotocin were evaluated. Some parameters presented significant differences among the experimental groups, but the effect of treatments to make better or worse the consequences of diabetes mellitus on liver was not detected using only the hepatocyte morphometry. The morphometric analysis evidenced that the white control group presented the highest mean values for nucleus and cytoplasm parameters, with the exception of the nuclear shape factor. However, this situation did not imply the diabetes mellitus was the cause of drastic reduction in these values, since the literature describes lower measurements for rats from the control group (non-diabetic rats).

Efeitos numéricos na simulação de escoamentos gás-sólido em leito fuidizado borbulhante utilizando a teoria cinética dos escoamentos granulares

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento de metodologias automáticas para obtenção do parâmetro de forma ótimo para o método RPIM

Neste trabalho, são propostas metodologias para otimização do parâmetro de forma local c do método RPIM (Radial Point Interpolation Method). Com as técnicas apresentadas, é possível reduzir problemas com inversão de matrizes comuns em métodos sem malha e, também, garantir um maior grau de liberdade e precisão para a utilização da técnica, já que se torna possível uma definição semi-automática dos fatores de forma mais adequados para cada domínio de suporte. Além disso, é apresentado um algoritmo baseado no Line Sweep para a geração eficiente dos domínios de suporte.

Modelagem da área foliar de duas cultivares de amendoim em função das dimensões lineares dos folíolos

The purpose of this study was to determine a shape factor to estimate area of leaflets of two peanut cultivars (IAC TATU ST, IAC RUNNER 886). Correlation studies were conducted involving real leaf area (Sf) and leaf length (C), maximum leaf width (L) and the product between C and L. For each cultivar was determined a form factor (f) by means of regression analysis between the product of the length by the width and the actual area of leaves and the correlation between leaf area estimated by the correction factor and direct measurement. All evaluated models (linear, exponential or geometric) provided good estimates of leaf area (above 87%). Linear models had the best fit, passing or not through the origin. From a practical viewpoint, it is suggested to use the linear model involving the C and L product, using a linear coefficient equal to zero, with values of factor f equal to 0.7111 and 0.7266 for IAC RUNNER 886 and IAC TATU ST, respectively. The method of dimensions is feasible for the estimation of leaf area for both peanut cultivars, for showing good r(2) values (0.97), with errors below 3%, even when used with independent data.

Toxoplasmosis: morphological and morphometric evaluation of spinal cord neurons from nonsymptomatic seropositive dogs

The aim of this work was to analyze the neuron morphology and morphometry of cervical, thoracic and lumbar areas of nonsymptomatic seropositive dogs’ spinal cord for toxoplasmosis. Twenty indefinite-breed adult dogs were used; ten dogs were healthy, with negative serology for toxoplasmosis, and were used as the control group (group 1), and ten dogs were nonsymptomatic but seropositive for toxoplasmosis (group 2). After the microtomy, with interval of 100 micrometers (µm), the histological 5-µm-thick cuts were dyed by hematoxylin-eosin and Masson's trichrome techniques. The glass slides were analyzed under light microscope to examine the neuron morphology. The parameters considered for the morphometric analysis were area, perimeter, maximum diameter, minimum diameter and shape factor of cytoplasm and nucleus of neuron. The results were statistically analyzed by Student’s t test at 5% probability level. The morphological characteristics between the two groups were similar and according to literature. The morphometric results showed that there were changes in neurons size and structure, and increase and loss of star shape were noticed in seropositive animals. The results suggest that the neurons of these dogs, yet nonsymptomatic, can have lost their conductor function.

Geoprocessamento aplicado na caracterização morfométrica da microbacia do Ribeirão Descalvado - Botucatu (SP)

The objective of this study was to evaluate geoprocessing to morphometrically characterize the Ribeirão Descalvado micro watershed – Botucatu, SP by the Geographic Information System (GIS) – Selva for preservation, rationalization of its use and environmental restoration. The micro watershed is 2,228.61 ha between the geographic coordinates: 22° 50' 05" to 22° 54' 26" latitude S and 48° 22' 29" to 48° 26' 36" longitude W Gr. The cartographic basis was the planialtimetric chart of Botucatu (SP), 1: 50000 scale (IBGE, 1969), used for extraction of level, hydrography and topography curves to determine morphometric indices. The results showed that low values of drainage density associated with the presence of permeable rocks facilitates ground water infiltration which decreases surface runoff, erosion risks and environmental degradation. The low value of the shape factor supported by the circularity index shows that the micro watershed is more elongated and at lower risk of more pronounced floods. The roughness coefficient environmental parameter classified the micro watershed for forest and reforestation.

Coccoliths and carbonate grain-size compositions in sediment samples from the Mid-Atlantic Ridge

This study presents a differentiated carbonate budget for marine surface sediments from the Mid-Atlantic Ridge of the South Atlantic, with results based on carbonate grain-size composition. Upon separation into sand, silt, and clay sub-fractions, the silt grain-size distribution was measured using a SediGraph 5100. We found regionally characteristic grain-size distributions with an overall minimum at 8 µm equivalent spherical diameter (ESD). SEM observations reveal that the coarse particles (>8 µm ESD) are attributed to planktic foraminifers and their fragments, and the fine particles (<8 µm ESD) to coccoliths. On the basis of this division, the regional variation of the contribution of foraminifers and coccoliths to the carbonate budget of the sediments are calculated. Foraminifer carbonate dominates the sediments in mesotropic regions whereas coccoliths contribute most carbonate in oligotrophic regions. The grain size of the coccolith share is constant over water depth, indicating a lower susceptibility for carbonate dissolution compared to foraminifers. Finally, the characteristic grain-size distribution in fine silt (<8 µm ESD) is set into context with the coccolith assemblage counted and biometrically measured using a SEM. The coccoliths present in the silt fraction are predominantly large species (length > 4 µm). Smaller species (length < 4 µm) belong to the clay fraction (<2 µm ESD). The average length of most frequent coccolith species is connected to prominent peaks in grain-size distributions (ESD) with a shape factor. The area below Gaussian distributions fitted to these peaks is suggested as a way to quantitatively estimate the carbonate contribution of single coccolith species more precisely compared to conventional volume estimates. The quantitative division of carbonate into the fraction produced by coccoliths and that secreted by foraminifers enables a more precise estimate for source/sink relations of consumed and released CO2 in the carbon cycle. The allocation of coccolith length and grain size (ESD) suggests size windows for the separation or accumulation of distinct coccolith species in investigations that depend on non to slightly-mixed signals (e.g., isotopic studies).

Intrasubject repeatability in keratoconus-eye measurements obtained with a new Scheimpflug photography–based system

Purpose: To evaluate in keratoconus eyes the intrasubject repeatability of anterior and posterior corneal curvature and of other anterior segment anatomic measurements obtained with a new topography system combining Scheimpflug-photography and Placido-disk technology. Setting: Vissum Corporation, Alicante, Spain. Design: Evaluation of technology. Methods: All keratoconus eyes had a comprehensive ophthalmologic examination including analysis with the Sirius system. Three consecutive measurements were obtained to assess the intrasubject repeatability of the following parameters: anterior and posterior corneal curvature and shape factor, white-to-white (WTW) corneal diameter, central and minimum corneal thickness, and anterior chamber depth (ACD). The within-subject standard deviation (Sw) and intraclass correlation coefficient (ICC) were calculated. Results: This study comprised 61 eyes of 61 patients ranging in age from 14 to 64 years. For anterior and posterior corneal curvatures and power vector components, the Sw was 0.29 mm or less in all cases. The ICC was above 0.990 in all cases except the flattest curvature of the posterior corneal surface at 3.0 mm, which was 0.840 (moderate agreement), and the posterior power vector J0, which was 0.665 (poor agreement), 0.752, and 0.758 (moderate agreement) for 3.0 mm, 5.0 mm, and 7.0 mm, respectively. In shape factor measurements, the Sw was 0.12 or less in all cases and the ICC ranged between 0.989 and 0.999. Pachymetry, ACD, and WTW had ICC values very close to 1. Conclusion: The new topography system provided repeatable measurements of corneal shape and other anatomic parameters in eyes with keratoconus.

Effective focal length through a microscope

Póster presentado en el VII European/ I World Meeting in Visual and Physiological Optics