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Rainfall forecasting and its spatio-temporal variability is important for many hydrological applications. It is critical to understand the uncertainty and verify the quality of rainfall forecasts provided by Numerical Weather Prediction (NWP) models. In the present study, the National Center for Environmental Prediction (NCEP) Global Forecast System (GFS) model performance is evaluated for day-1 to day-5 forecast with a threshold of 1 mm/day in the Nagavali and Vamsadhara river basins, India. From the results, the model predicted the rainfall with a correlation coefficient of >0.3 and probability of detection >0.6 for day-1 and day-3 forecasts. The bias in rainfall prediction shifted from overestimation to underestimation by 30% as forecast lead time increased. The total mean error is decomposed into hit, false, and missed bias. The main sources of total mean error are hit bias and false bias. However, missed bias influenced total mean error as lead time increased. Bias correction is applied for the rainfall events with a rainfall intensity >12 mm/day. RMSE improved by >18% for day-1 forecast in both the Nagavali and Vamsadhara basins, and the improvement ranged between 3% to 9% for other days. In the Nagavali basin, BIAS and ME improved and ranged from 44% to 65% for day-1 to day-5 forecast, whereas in the Vamsadhara basin, it ranged from 65% to 93%. Our findings are useful for early warning dissemination during the flood events, resource mobilization to protect communities, and sustainable water resources planning and management. • The skill of the NCEP GFS model to forecast precipitation was examined. • For day-1 to day-3 forecasts, a correlation of >0.3 was seen. • Bias correction for rainfall intensities >12 mm/day required. • GFS rainfall forecasts useful for flood and water management in the tropics. [ABSTRACT FROM AUTHOR]

Abstract: Cadmium indate films were deposited by dc reactive magnetron sputtering onto glass substrates in an oxygen partial pressure of 5×10−4 mbar and at various substrate temperatures in the range 373–673 K. The influence of substrate temperature on the structural, electrical and optical properties of the films was systematically studied. The films formed at substrate temperatures <423 K were amorphous while those deposited at ≥423 K were polycrystalline with cubic spinel structure. The decrease of electrical resistivity and increase of Hall mobility with the increase of substrate temperature were due to the improvement in the crystallinity of the films. The temperature dependence of Hall mobility measurements indicated that the grain boundary scattering of charge carriers was predominant in the films. The films formed at a substrate temperature of 673 K exhibited an electrical resistivity of 3.5×10−4 Ω cm, Hall mobility of 29 cm2 V−1 s−1, optical transmittance of 88%, optical band gap of 3.28 eV and figure of merit of 5×10−2 Ω−1. [Copyright &y& Elsevier]

Abstract: Thin films of cuprous oxide (Cu2O) were deposited on glass substrates at various bias voltages using DC reactive magnetron sputtering technique. The effects of substrate bias voltage on structural, electrical and optical properties were systematically analyzed. The crystallographic structure and orientation of the crystallites were strongly influenced by the bias voltage. [Copyright &y& Elsevier]

Transparent conducting cadmium indate films were deposited at different oxygen partial pressures in the range from 1×10−4 to 5×10−3 mbar onto glass substrates maintained at a temperature of 523 K by dc magnetron sputtering from a cadmium–indium alloy target at a sputtering pressure of 4×10−2 mbar. The films were characterised by studying the influence of oxygen partial pressure on the structural, electrical and optical properties. Cadmium indate films formed at an oxygen partial pressure of 5×10−4 mbar were polycrystalline with cubic spinel structure, low electrical resistivity of 1.2×10−3 Ω cm, high optical transmittance of 87% in the visible region, optical band gap of 3.23 eV and a figure of merit of 1.8×10−3 Ω−1. [Copyright &y& Elsevier]

Optical absorption studies on vacuum flash evaporated polycrystalline Cu0.5Ag0.5InSe2 thin films are reported. The absorption humps observed in the spectra are attributed to transitions from the valence sub-bands to the conduction band. From the optical transmittance data, the optical band gap energies, spin–orbit and crystal-field parameters are determined. [Copyright &y& Elsevier]

A compact Photoacoustic spectrometer (PAS) was fabricated, for the determination of phase transitions in liquid crystals (LCs). Photoacoustic (PA) technique is a powerful tool for the determination of phase transitions in solids, liquids and gasses compared to other techniques like Raman spectroscopy, Newton scattering, NMR & ultrasound studies and DSC. PA signal information is used to investigate the variations in the optical and thermal properties of the materials during phase transitions. The advantage of PA technique is its simplicity in the sample preparation, and its accuracy in the phase transition studies. The instrumentation details and results of phase transition studies on p-pentyloxy benzoic acid (5OBA), N(4-n-hexadcyloxysalicylidene)-2-methylbutyl-4'-amino-cinnamate, 16O(OH)2MBC and N-(4-n-butyloxysalicylidene)-4'-n-Ketylaniline, 4O(OH)5 are presented. The advantages of PA technique are elaborated. [ABSTRACT FROM AUTHOR]

An attempt has been made to study the continuous drive friction welding characteristics of AISI 430 ferritic stainless steel. All the welds exhibited fine equiaxed ferritic grains. Parameters that result in marginally coarse grain size in the bond zone led to low hardness and high toughness. Welds having a fine grain size exhibited higher hardness and superior notch tensile strength. An inverse relationship was observed between impact toughness and notch tensile strength. Regression analysis of the data revealed a high degree of correlation. It was concluded that the selection of parameters would depend on the property of interest. [ABSTRACT FROM AUTHOR]