Estimation of the volumetric oxygen tranfer coefficient (KLa) from the gas balance and using a neural network technique

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

Comparação de três métodos de estimativa da evapotranspiração de referência para a região de Araraquara - SP

Uma forma de verificar a eficiência de métodos de estimativa da evapotranspiração de referência (ETo) é a comparação com o método-padrão. Este trabalho tem por finalidade comparar três métodos de estimativa da ETo: Radiação Solar (RS), Makkink (MAK) e Tanque Classe A (TCA) em relação ao método de Penman-Monteith (PM), em dois períodos distintos das fases de desenvolvimento da cultura de citros, com dados médios quinzenais para os períodos inverno-primavera e verão-outono. A pesquisa foi desenvolvida em uma fazenda de citros, em Araraquara - SP, onde foi instalada uma estação meteorológica automatizada e um tanque Classe A. Por intermédio da estação meteorológica automatizada, foram obtidas medidas da radiação solar global, saldo de radiação, temperatura do ar, umidade relativa do ar e velocidade do vento. A análise de regressão indica que, para o método TCA, pode ser utilizado o modelo de regressão y = bx, em que, y representa a EToPM e x a EToTCA. Para os demais métodos analisados, o modelo mais adequado foi y = bx + a. Os resultados obtidos neste estudo evidenciam que o método do TCA superestimou a ETo em 26% no período verão-outono e em 24% no período inverno-primavera. O método de MAK subestimou a ETo nos dois períodos analisados, enquanto o método da RS superestimou a ETo.

An application of neural network technique to correct the dome temperature effects on pyrgeometer measurements

This work describes an application of a multilayer perceptron neural network technique to correct dome emission effects on longwave atmospheric radiation measurements carried out using an Eppley Precision Infrared Radiometer (PIR) pyrgeometer. It is shown that approximately 7-month-long measurements of dome and case temperatures and meteorological variables available in regular surface stations (global solar radiation, air temperature, and air relative humidity) are enough to train the neural network algorithm and correct the observed longwave radiation for dome temperature effects in surface stations with climates similar to that of the city of São Paulo, Brazil. The network was trained using data from 15 October 2003 to 7 January 2004 and verified using data, not present during the network-training period, from 8 January to 30 April 2004. The longwave radiation values generated by the neural network technique were very similar to the values obtained by Fairall et al., assumed here as the reference approach to correct dome emission effects in PIR pyrgeometers. Compared to the empirical approach the neural network technique is less limited to sensor type and time of day (allows nighttime corrections).

A software to process daily solar radiation data

This work presents one software developed to process solar radiation data. This software can be used in meteorological and climatic stations, and also as a support for solar radiation measurements in researches of solar energy availability allowing data quality control, statistical calculations and validation of models, as well as ease interchanging of data. (C) 1999 Elsevier B.V. Ltd. All rights reserved.

Linear low density polyethylene (LLDPE) from ethylene using Tp(Ms)NiCl (Tp(Ms) = hydridotris(3-mesitylpyrazol-1-yl)) and CP2ZrCl2 as a tandem catalyst system

Linear low density polyethylene (LLDPE) with different branching contents were prepared from ethylene, without the addition of alpha-olefin comonomer, using a combination of catalyst precursors {Tp(Ms)}NiCl (1) (Tp(Ms) = hydridotris(3-mesitylpyrazol-1-yl)) and Cp2ZrCl2 (2) activated with MAO/TMA (1:1) in toluene at 0degreesC and by varying the nickel loading mole fraction (x(Ni)). The polymerization results showed that the turnover frequencies are strongly dependent on the x(Ni) varying from 6.6 x 10(3) to 32.1 x 10(3) mol[C2H4]/mol[Zr] h. The C-13 NMR spectra of the copolymers showed that the branch contents of the polymers increase as the x(Ni) increase in the medium promoting the production of polymers with a wide range of melting point (T-m) (C) 2004 Elsevier B.V. All rights reserved.

Análise da frequência anual das condições de céu em Botucatu, São Paulo

This paper presents an analysis of the frequency of the sky conditions in Botucatu. The classification of sky conditions was made based on the clearness index (K T), calculated from a database with 10 years of measured daily global solar radiation. Throughout the year in Botucatu, there is a predominance of days with clear sky condition, on average 114 days. For cloudy sky condition, the average frequency is 61 days. About the two intermediate sky conditions, the frequency of the sky partially cloudy with dominance for the diffuse is 94 days and the one with dominance for the clear is 96 days. The main influential factors on the sky conditions in Botucatu are the inputs of cold fronts and the formation of the South Atlantic Convergence Zone. They respond primarily by altering the sky condition of clear to cloudy or partially cloudy with dominance to diffuse. The aerosols resulting from burning in sugarcane fields respond by altering the sky condition from clear to partly cloudy with dominance for the clear.

Numerical correction for the diffuse solar irradiance by the melo-escobedo shadowring measuring method

The present paper deals with numerical corrections factors proposed as a function of the clearness index in order to correct the diffuse solar irradiance measured with the Melo-Escobedo Shadowring Measuring Method (ME shadowring). The global irradiance was measured by an Eppley - PSP pyranometer ; direct normal irradiance by an Eppley-NIP pyrheliometer fitted to a ST-3 sun tracking device and the diffuse irradiance by an Eppley-PSP pyranometer fitted to a ME shadowring. The validations were performed by the MBE and RMSE statistical indicators. The results showed that the numerical correction factors were appropriate to correct the shadowring diffuse irradiance.

Avaliação de diferentes inclinações e exposições de telhado em três tipos de cobertura em modelos reduzidos de instalações zootécnicas

The present study was developed in Departamentos de Engenharia Rural e Morfologia e Fisiologia Animal da FCAV/Unesp. The objective of evaluating different roof slopes and exposure in three types of coverage in models of animal installations. Project 48 built reduced models of wood were used with dimensions of 1,00 x 1,00 x 0,50 meters. The covering was one water, lateral and wood floor, disposed in the exhibitions North-south, being 24 prototypes in the north exhibition and 24 in the south. Were used in the covering roofs of ceramic type, galvanized steel and asbestos. The slopes varied of 20, 30, 40 and 50% for ceramic tile and 10, 30, 40 and 50% for the others and with two repetitions for slope. Inside the reduced models temperature readings were accomplished, of hour in hour during one year, for the system of acquisition of Data Logger Campbell Scientific-Ínc and externally the temperature of the air, incident radiation global solar, precipitation, speed and relative humidity of the air were measured. The results obtained during the experimental period of one year were appraised statistically for the statistical package SAS in the factorial outline, where three factors were considered: tile type, slope degree and exposure. The obtained averages were compared through the test of Tukey to 5% of probability. After analyzing the data we found that with increasing slope, there was a decrease in inside temperature in the cover prototypes, therefore, using steeper slopes with 50% of tipping ceramics and asbestos, with greater coverage on display South, we have lower temperatures in poultry houses in the geographic coordinates of the city of Jaboticabal.

Estimativas da radiação global incidente em superfícies inclinadas com base na razáo de insolação

Estimating equations of global radiation based on the sunshine duration were proposed for horizontal surface and with inclination of 12.85, 22.85 and 32.85° facing the North in Botucatu, SP, Brazil, in monthly, seasonal and annual groupings of data. Simple linear correlations were applied (for definition of the linear and angular coefficients of Angstrom-Prescott model), in a database measured in all three inclinations in different periods (22.85°: 04/1998 to 07/2001; 12.85°: 08/2011 to 02/2003; and 32.85°: 03/2003 to 12/2007) concomitant with horizontal measures and sunshine duration. The statistical performance of the model was analysed by the means absolute error (MBE), the square root of the mean square error (RMSE) and the index adjustment (d). The minimum global radiation transmissivity varied from 14.35% in August (12.85°) to 27.86% in December (32.85°) and the maximum transmissivity ranged between 62.10% and 78.90%, for June (32.85°) and December (12.85°). Increasing the angle of inclination surface increased the scattering and decreased the index of adjustment and performance. The worst results were found for application of the seasonal and annual models in the months of autumn and winter for 32.85° (RMSE below 42.93% and adjustment superior to 0.4693).

Análise de três métodos de estimativa da evapotranspiração de referência para a região de Pradópolis - SP

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Determinação do consumo de água em cultura de pimentão (Capsicum annuum L.) em ambiente protegido

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Avaliação de diferentes materiais de cobertura, inclinações e exposições de telhado na temperatura interna em modelos reduzidos de instalações zootécnicas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Analytical prediction of the spin stabilized satellite's attitude using the solar radiation torque

The aim of this paper is to present an analytical solution for the spin motion equations of spin-stabilized satellite considering only the influence of solar radiation torque. The theory uses a cylindrical satellite on a circular orbit and considers that the satellite is always illuminated. The average components of this torque were determined over an orbital period. These components are substituted in the spin motion equations in order to get an analytical solution for the right ascension and declination of the satellite spin axis. The time evolution for the pointing deviation of the spin axis was also analyzed. These solutions were numerically implemented and compared with real data of the Brazilian Satellite of Data Collection - SCD1 an SCD2. The results show that the theory has consistency and can be applied to predict the spin motion of spin-stabilized artificial satellites.

Search for gravitational radiation from intermediate mass black hole binaries in data from the second LIGO-Virgo joint science run

This paper reports on an unmodeled, all-sky search for gravitational waves from merging intermediate mass black hole binaries (IMBHB). The search was performed on data from the second joint science run of the LIGO and Virgo detectors (July 2009-October 2010) and was sensitive to IMBHBs with a range up to similar to 200 Mpc, averaged over the possible sky positions and inclinations of the binaries with respect to the line of sight. No significant candidate was found. Upper limits on the coalescence-rate density of nonspinning IMBHBs with total masses between 100 and 450 M-circle dot and mass ratios between 0.25 and 1 were placed by combining this analysis with an analogous search performed on data from the first LIGO-Virgo joint science run (November 2005-October 2007). The most stringent limit was set for systems consisting of two 88 M-circle dot black holes and is equal to 0.12 Mpc(-3) Myr(-1) at the 90% confidence level. This paper also presents the first estimate, for the case of an unmodeled analysis, of the impact on the search range of IMBHB spin configurations: the visible volume for IMBHBs with nonspinning components is roughly doubled for a population of IMBHBs with spins aligned with the binary's orbital angular momentum and uniformly distributed in the dimensionless spin parameter up to 0.8, whereas an analogous population with antialigned spins decreases the visible volume by similar to 20%.

WIMP and SIMP dark matter from the spontaneous breaking of a global group

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