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Belur, India

Ramakrishna Mission Vivekananda University is a university that is administered by the Ramakrishna Mission. It was declared by Government of India as a Deemed University under Section 3 of UGC Act, 1956. It has four campuses in Belur, Coimbatore, Ranchi and Narendrapur.The university was given the status of a deemed university in July 2005. It provides courses on subjects as varied as rural and tribal development, disability management and special education, fundamental science education and Indian cultural and spiritual heritage.The university's School of Mathematical Science started its academic activities in July 2008. The classes are conducted at the main campus of the university at Belur and at Vivekananda Research Centre, the ancestral house of Swami Vivekananda in Kolkata.The university is also conducting these courses at its specialized faculty centers throughout the country. Other unconventional areas that the university is engaged in are disability management and special education at Coimbatore, integrated rural development including tribal development and management at its centers in Ranchi and Narendrapur. Wikipedia.

Sharma A.,Texas Tech University | Weindorf D.C.,Texas Tech University | Wang D.,Nanjing University of Information Science and Technology | Chakraborty S.,Ramakrishna Mission Vivekananda University

Soil cation exchange capacity (CEC) is an important measure of soil fertility, owing to the large number of plant essential nutrients which are taken up by plants as cations. However, current methods for evaluating soil CEC are arduous and require analysis in a laboratory. Portable X-ray fluorescence (PXRF) spectrometry is a proximal sensing technique which provides elemental data in-situ, in seconds. This study examined the potential of using PXRF for soil CEC prediction by evaluating 450 soil samples from California and Nebraska, USA representing a wide variety of soil textures found in active farm fields. Multiple linear regression was applied to a modeling dataset to establish the relationship between lab-determined CEC and PXRF elemental data. A second model also included auxiliary input data (soil clay, pH, organic matter) as potential modeling variables. Both models were shown to perform similarly, with the auxiliary input model providing slightly higher R2 (0.926 vs. 0.908) and slightly lower RMSEs (2.236 vs. 2.498) compared to pure elemental data models. Independent validation datasets were compelling for both pure elemental models (0.904) and auxiliary input models (0.953). Summarily, PXRF was able to predict soil CEC accurately, thereby minimizing the need for lab-based CEC data for many applications. © 2014 Elsevier B.V. Source

Dey R.,Max Planck Institute for Plasma Physics (Garching) | Roy A.C.,Ramakrishna Mission Vivekananda University
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms

We report triply differential cross section (TDCS) for the simultaneous excitation-ionization of helium by electron impact for both coplanar and non-coplanar geometry. In the coplanar case, calculations have been performed for an incident energy of 500 eV and low ejection energies (3 and 10 eV), whereas in the noncoplanar case we have considered impact energies in the range 1240-4260 eV for a symmetric geometry. The present calculation is based on the eikonal approximation due to Glauber. We have incorporated the effect of post-collision interaction in the Glauber approximation. A comparison is made of the present calculations with the results of other theoretical methods and recent experiments. The Glauber results are in reasonably good agreement with the experiment for small scattering angles. © 2010 Elsevier B.V. All rights reserved. Source

Aldabaa A.A.A.,Desert Research Center | Weindorf D.C.,Texas Tech University | Chakraborty S.,Ramakrishna Mission Vivekananda University | Sharma A.,Texas Tech University | Li B.,Louisiana State University

Salt affected soils are pervasive in semiarid and arid regions worldwide. Traditionally, soil salinity has been measured via electrical conductivity (EC). This study evaluated the feasibility of using three different methods for prediction of surface soil salinity, namely visible near infrared diffuse reflectance spectroscopy (VisNIR DRS), portable x-ray fluorescence (PXRF) spectrometry, and remote sensing (RS). Two saline playas were evaluated in West Texas, USA featuring 91 and 74 soils collected via random stratified sampling at 0-5cm and representing a wide variety of soil salinity from high levels inside the playa bottoms to lower levels on the annulus and surrounding uplands. Samples were subjected to PXRF and VisNIR DRS scanning under laboratory conditions, and compared to Landsat spectral data and traditional laboratory analyses of salinity (e.g., 1:5 v/v suspensions). Results showed a broad range of EC (1:5) (0.028 to 43.41dSm-1). Derived from PXRF, both Cl and S were significantly and positively correlated with log10 transformed EC (1:5). VisNIR partial least squares prediction models produced strong residual prediction deviations (RPDs) of 2.49-2.91. Validation statistics of Savitzky-Golay support vector regression outperformed all other VisNIR models tested with an RPD of 3.1. The model using Landsat band reflectance alone produced lowest prediction accuracy (RPD=1.27). While the performance of each technique produced variable success independently, combining the three techniques produced the highest predictability (RPD=3.35). Given that, laboratory determination of EC (1:5) is time consuming and all three types of data (VisNIR DRS, PXRF, and RS) are being quick and easy to collect, their synthesis in predictive models offers excellent potential for providing soil salinity measurements comparable to standard, laboratory derived data. Furthermore, remotely sensed data can potentially be used to map topsoil salinity across large areas with suitable calibrations. © 2014 The Authors. Published by Elsevier B.V. Source

Samanta A.,Ramakrishna Mission Vivekananda University | Samanta A.,Abdus Salam International Center For Theoretical Physics | Smirnov A.Yu.,Abdus Salam International Center For Theoretical Physics
Journal of High Energy Physics

We study dependence of the atmospheric νμ and νμ uxes on the deviations of the 2-3 mixing from maximal, |45°-θ23|, on the θ23-octant and on the neutrino mass splitting Δm 32 2. Analytic expressions for the θ23- deviation e ect and the octant asymmetry are derived. We present conservative estimations of sensitivities of the iron (magnetized) calorimeter detectors (ICAL) to these parameters. ICAL can establish the θ23- deviation at higher than 3σ confidence level if |45°- θ23 < 6° with the exposure of 1 Mton·yr. Sensitivity to the octant is low for zero or very small 1-3 mixing, but it can be substantially enhanced for θ13 3°. ICAL can measure the di erence of Delta;m32 2 in ν and ν channels (the CPT test) with accuracy 0:8×10-4 eV2 (3σ) with 1 Mton·yr exposure, and the present MINOS result can be excluded at < 5σ confidence level. We discuss possible ways to further improve sensitivity of the magnetized spectrometers. © SISSA 2011. Source

Sen S.,Visva Bharati | Mandal P.,Visva Bharati | Mukherjee P.K.,Visva Bharati | Mukherjee P.K.,Ramakrishna Mission Vivekananda University
Physics of Plasmas

Pilot calculations on the hyperpolarizability of He, the first neutral member of the two electron sequence, have been performed under spherical confinement with a view to analyse the effect of pressure on such non linear optical properties. Detailed investigations have also been performed for the first time on the hyperpolarizability due to the effect of screened Coulomb potential obtained from a surrounding Debye plasma environment. Variation perturbation theory within coupled Hartree-Fock scheme has been adopted to estimate the non linear optical properties under such external confinement. For a given plasma coupling strength, the hyperpolarizability value is found to reduce systematically with decrease of radius of confinement, while the same is found to increase continuously with increasing plasma coupling strength determined by gradual enhancement of the screening parameter for a given radius of confinement. Under strong confinement the hyperpolarizability value is found to be negative. The estimated free atom hyperpolarizability is consistent with the existing coupled Hartree-Fock result. © 2012 American Institute of Physics. Source

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