10,638 research outputs found

    Long range prediction of Indian summer monsoon rainfall

    Get PDF
    The search for new parameters for predicting the all India summer monsoon rainfall (AISMR) has been an important aspect of long range prediction of AISMR. In recent years NCEP/NCAR reanalysis has improved the geographical coverage and availability of the data and this can be easily updated. In this study using NCEP/NCAR reanalysis data on temperature, zonal and meridional wind at different pressure levels, few predictors are identified and a prediction scheme is developed for predicting AISMR. The regression coefficients are computed by stepwise multiple regression procedure. The final equation explained 87 of the variance with multiple correlation coefficient (MCC), 0.934. The estimated rainfall in the, El-Niño year of 1997 was -1.7 as against actual of 4.4. The estimated rainfall deficiency in both the recent deficient years of 2002 and 2004 were -19.5 and -8.5 as against observed -20.4 and -11.5 respectively

    Satellite Coastal and Oceanographic Research Inter-comparison Exercise (SICOME)

    Get PDF
    INCOIS is coordinating Satellite Coastal and Oceanographic Research (SATCORE) project SATCORE programme since XIth plan with an aim of long-term measurements of bio-optical properties in the Indian coastal waters. The principal aim of these measurements is continuous measurement of in situ bio-optical data for validation of existing ocean color algorithms, improvement, development of new bio-optical algorithms in coastal waters of India. INCOIS had identified 12 time series sampling transects along east and west of India for continuous measurement of bio-optical parameters. Regular in situ sampling and analysis at time series stations are carried out by sub-projects sanctioned under SATCORE program to various Research and Academic &D Institutions: Junagadh Agricultural University (Off Okha), NIO, Goa (Off Goa), Goa University (Off Goa), Mangalore University (Off Mangalore), CIFT, Kochi (Off Kochi), Annamalai University (Off Parangipettai), IIT Madras (Off Chennai), Andhra University (Off Visakhapatnam), CSBoB, Andhra University (Off Visakhapatnam), Berhampur University (Off Gopalpur), Jadavpur University (Off Frazergunj), CARI (ICAR) (A & N Islands). To ensure the accuracy of the parameters measured at vasrious laboratories at different time-series locations, Satellite Coastal and Oceanographic Research-Inter-comparison Exercises (SICOME) were conducted during 2014 and 2015. During SICOME samples of Optically Active Substances i.e chlorophyll-a (chl-a), coloured dissolved organic matter (CDOM) and total suspended matter (TSM) were collected from one location. The master samples were immediately analyzed and duplicate samples were sent to different SATCORE laboratories. All the fluorometers were calibrated with teh standards for chlorophyll-a, Chromophoric Dissolved Organic Matter (CDOM) and Turbidity. All five Radiometers were also operated simultaneously to estimate the instrument bias. The document provides results of the instrument and analytical bias for same samples analyzed at various SATCORE laboratories so as to maintain the data quality for international standard

    Classical orbital paramagnetism in non-equilibrium steady state

    Full text link
    We report the results of our numerical simulation of classical-dissipative dynamics of a charged particle subjected to a non-markovian stochastic forcing. We find that the system develops a steady-state orbital magnetic moment in the presence of a static magnetic field. Very significantly, the sign of the orbital magnetic moment turns out to be {\it paramagnetic} for our choice of parameters, varied over a wide range. This is shown specifically for the case of classical dynamics driven by a Kubo-Anderson type non-markovian noise. Natural spatial boundary condition was imposed through (1) a soft (harmonic) confining potential, and (2) a hard potential, approximating a reflecting wall. There was no noticeable qualitative difference. What appears to be crucial to the orbital magnetic effect noticed here is the non-markovian property of the driving noise chosen. Experimental realization of this effect on the laboratory scale, and its possible implications are briefly discussed. We would like to emphasize that the above steady-state classical orbital paramagnetic moment complements, rather than contradicts the Bohr-van Leeuwen (BvL) theorem on the absence of classical orbital diamagnetism in thermodynamic equilibrium.Comment: 6 pages, 4 figures, Has appeared in Journal of Astrophysics and Astronomy special issue on 'Physics of Neutron Stars and Related Objects', celebrating the 75th birth-year of G. Srinivasa

    Cyclone Phailin enhanced the productivity following its passage: Evidence from satellite data

    Get PDF
    Over the past decade (2002–2013) the Bay of Bengal has experienced 12 cyclones and 27 tropical storms. The recent one was the cyclone Phailin which was equivalent to a category-5 hurricane on the Saffir–Simpson hurricane wind scale(SSHWS). The cyclonic storm developed over the north of Andaman and Nicobar Islands on 9 October 2013. Subsequen tly,it propagated towards north-northwest and made a landfall at the Gopalpur coast of south Odisha on 12 October

    Study of spatial-temporal variations in the green Noctiluca scintillans and diatom blooms in the Arabian Sea using MODIS data

    Get PDF
    Phytoplankton blooms of green Noctiluca scintillans (a dinoflagellate) and diatom, which appear in the Northern and Central Arabian Sea during winter are far-reaching and persistent. Generation of phytoplankton species images revealed a massive winter bloom with huge spatial extent in 2015. In contrast to this, the classified species images for 2013 indicated relatively weaker bloom with respect to its spread. A plot of total number of pixels classified as diatom and Noctiluca scintillans for different years revealed a cyclic pattern of the spread. The report deals with an approach to forecast the bloom / productivity of the oceanic waters in the Northern-Central Arabian Sea in a qualitative way making use of the systematic pattern of its distribution across the year

    Design and Process control of Siemens polysilicon CVD reactor

    Get PDF
    The novelty in this paper is to develop a process control for the poly-silicon CVD reactor to achieve optimum productivity of Poly-silicon seed by controlling the process parameters. The production of ingot is done through Siemens process of decomposing Trichlorosilane by Chemical Vapor Deposition on slim tungsten rods. The hardware architecture proposed monitors and controls the systematic sequential stages furnishing dynamics of the plant at a high temperature around 1050°C-1100°C. The HMI communicates through NI's LabVIEW 8.6 package, alarming the user with Process mimic, Report generation, Data and Security management. The plant simulation is realized and verified with LabVIEW 8.6 Version and MATLab 7.5 software tools to obtain the effectiveness of proposed control technique. This GUI based SCADA handles likelihood of fault tolerance, ensuring risk controlled process with optimum productivity of poly-silicon by making system compliant to Industrial standards

    On forecasting the Indian summer monsoon: The intriguing season of 2002

    Get PDF
    This year, the rainfall over India during the first half of the summer monsoon season was 30 below normal. This has naturally led to a lot of concern and speculation about the causes. We have shown that the deficit in rainfall is a part of the natural variability. Analysis of the past data suggests that there is a 78 chance that seasonal mean rainfall this year will be 10 or more below the long-term average value. We discuss briefly how forecasts for seasonal rainfall are generated, whether this event could have been foreseen, and share our perspective on the problems and prospects of forecasting the summer monsoon rainfall over the Indian region

    Surgicel as an Unusual Cause of Prolonged Drainage

    Get PDF
    No Abstract: Letter to Edito

    Genomic DNA isolation from Artemisia species grown in cold desert high altitude of India

    Get PDF
    Artemisia which produces a large number of secondary metabolites is naturally found in cold desert high altitude environment of India. Secondary metabolites such as alkaloids, flavonoids, phenols, polysaccharides and terpenes represent a significant barrier to the extraction of pure genomic DNA. Thus, in this study, the DNA extraction protocol to extract pure genomic DNA from different Artemisia species was tailored. The protocol was based on the CTAB method with slight modifications. In the study, 1.6 M NaCl, 2% cetyltrimethyl ammonium bromide (CTAB), 3% polyvinylpyrrolidone (PVP) and 0.5% β-mercaptoethanol was used in the extraction buffer. The incubation period was kept for 1 h at 65°C with one-tenth of the volume of warm (55°C) 10% CTAB solution during the extraction process. This study described a reliable protocol for extracting good quality and optimum amount of DNA from Artemisia species suitable for PCR analysis.Key words: Artemisia, genomic DNA isolation, PCR amplification, secondary metabolites

    Effects of powder characteristics and chemical composition on the properties of 25Cr7Ni stainless steel fabricated by laser-powder bed fusion and evaluation of process simulation

    Get PDF
    The 25Cr7Ni stainless steel alloy system is gaining increasing interest in the oil and gas industry because of its combination of high strength and corrosion resistance properties. However, very few studies on the effects of starting powder attributes and chemical composition on the as-printed properties of 25Cr7Ni stainless steel fabricated through laser-powder bed fusion (L-PBF) exist in the literature. This study examined the influence of powder attributes and chemical composition on the samples from gas atomized and water atomized 25Cr7Ni stainless steel powders, fabricated through L-PBF, on their as-printed microstructure and properties. The mechanical properties that were examined included ultimate tensile strength (UTS), elongation (%), and hardness. The corrosion behavior was also studied using linear sweep voltammetry in 3.5 wt.% NaCl solution. The evolved phases were characterized using optical and scanning electron microscopy, as well as through X-ray diffraction. The gas atomized powders, with their spherical and uniform morphology, yielded as-printed parts of higher relative densities when compared to water atomized powders, with irregular morphology due to better powder bed compaction. The higher densification obtained in the L-PBF samples from gas atomized powders translated into the highest UTS, hardness, and yield strength among the L-PBF samples from water atomized powders and wrought–annealed 25Cr7Ni stainless steel. The presence of higher amounts of N and Mn in the chemical composition of the gas atomized powders over water atomized powders promoted the presence of retained austenite in the corresponding L-PBF samples. Higher amounts of Mo, combined with austenite content, yielded a higher corrosion resistance in the L-PBF samples from the gas atomized powder than in the L-PBF samples from the water atomized powders. The latter part of the work is focused on the evaluation of simulation parameters for analyzing the fabrication procedure for the L-PBF process using Simufact software. For a given set of process parameters, Simufact provides the distortion and internal stresses developed in the printed parts as output. The present study sought to evaluate the process simulation by comparing the experimental observations in terms of the part distortion achieved in a stainless steel cube fabricated through L-PBF with Simufact process simulation obtained using the same set of process parameters
    corecore