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Search Results: 1 - 10 of 218 matches for " Arup Borgohain "
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SO2 Oxidation Efficiency Patterns during an Episode of Plume Transport over Northeast India: Implications to an OH Minimum  [PDF]
Timmy Francis, Shyam Sundar Kundu, Ramabadran Rengarajan, Arup Borgohain
Journal of Environmental Protection (JEP) , 2017, DOI: 10.4236/jep.2017.810071
Abstract: Systematic monitoring of the fluctuations in atmospheric SO2 oxidation efficiency—measured as a molar ratio of SO42- to total SOx (SOx=SO2+SO42-), referred as S-ratio—have been performed during a major long range plume transport to northeast India (Shillong: 25.67°N, 91.91°E, 1064 m ASL) in March 2009. Anomalously low S-ratios (median, 0.03) were observed during the episode—associated with a cyclonic circulation—and the SO42- and SO2 exhibited unusual features in the ‘relative phase’ of their peaks. During initial days, when SO2 levels were dictated by the long range influx, the SO42- and SO2 variabilities were in anti-phase—for the differing mobility/loss mechanisms. When SO2 levels were governed by the boundary layer diurnality in the latter days, the anti-phase is explained by a ‘depleted OH level’—major portion being consumed in the initial period by the elevated SO2 and other pollutants. Simulations with a global 3D chemical transport model, GEOS-Chem (v8-03-01), also indicated ‘suppressed oxidation conditions’—with characteristic low S-ratios and poor phase agreements. The modelled OH decreased steadily from the initial days, and OH normalized to SO2—referred as OHspecific—was consistently low during the ‘suppressed S-ratio period’. Further, the geographical distribution of modelled OH showed a pronounced minimum over the region surrounding (20°N, 95°E) spanning parts of northeast India and the adjacent regions to the southeast of it—prevalent throughout the year, though the magnitude and the area of influence have a seasonality to it—with significant implications for reducing the oxidizing power of the regional atmosphere. A second set of measurements during January 2010—when prominent long range transports were absent—exhibited no anomalies, and the S-ratios were well within the acceptable limits (median, 0.32). This work highlights the GEOS-Chem model skill in simulating/detecting the ‘transient fluctuations’ in the oxidation efficiency, down to a regional scale.
Spatial Variability and Radiative Impact of Aerosol along the Brahmaputra River Valley in India: Results from a Campaign  [PDF]
Shyam Sundar Kundu, Arup Borgohain, Nilamoni Barman, Meenakshi Devi, P. L. N. Raju
Journal of Environmental Protection (JEP) , 2018, DOI: 10.4236/jep.2018.94026
Abstract: The first ever land campaign to study the spatial variability of the aerosol characteristics along the Brahmaputra river valley (BRV) in Assam, North-Eastern India, was conducted during 2011. Measurements were made over 13 locations for Aerosol Optical Depth (AOD), scattering coefficient, particulate matter, black carbon (BC) concentration and meteorological parameters. The BRV is divided into three sectors longitudinally viz western sector (WS), central sector (CS), and eastern sector (ES). Significant Spatial heterogeneity in AOD and BC concentration was observed (p < 0.05) with the highest values over WS and a continual decrease from WS to ES with aerosol dominance in PM2.5 category along the entire valley. The Angstrom coefficient measured using different wavelength pairs showed spatial variability indicating dominance of fine particles over WS and coarse particles in ES with a probable bimodal distribution. The scattering and absorption coefficient shows dominance of both types of aerosol over WS than other areas. The shortwave radiative forcing was higher over the WS than CS and ES of the valley. The campaign revealed that under favorable wind conditions, the BRV is loaded with significant amount of natural and anthropogenic aerosol during local winter and is influenced by the long-range transport of aerosols from the Indo-Gangetic plain.
Golden Research Thoughts , 2013, DOI: 10.9780/22315063
Abstract: The rural mass of Sivasagar district are primarily dependent on Agriculture. Farming has been the mainstay of the large majority of the people. Settled cultivation is the general characteristics and rice has been the most dominant crop activity in the area. Of course, mustard, sugarcane, pulses and various types of vegetables are also grown to a limited expect. In addition dairy, poultry, piggery, sericulture, weaving and fishery are some of the subsidiary occupation of the inhabitants of the area. However, the entire area under this sector are lagging behind due to lack of proper policies on utilization of farm land, lack of extension services, poor purchasing capacity of majority of the people, negligible investment in farm production and lack of technologies along with the inertia of remaining in the traditional set up of the farming community of the area
Data Hiding Techniques using number decompositions
Rajdeep Borgohain
Computer Science , 2012,
Abstract: Data hiding is the art of embedding data into digital media in a way such that the existence of data remains concealed from everyone except the intended recipient. In this paper, we discuss the various Least Significant Bit (LSB) data hiding techniques. We first look at the classical LSB data hiding technique and the method to embed secret data into cover media by bit manipulation. We also take a look at the data hiding technique by bit plane decomposition based on Fibonacci numbers. This method generates more bit planes which allows users to embed more data into the cover image without causing significant distortion. We also discuss the data hiding technique based on bit plane decomposition by prime numbers and natural numbers. These methods are based on mapping the sequence of image bit size to the decomposed bit number to hide the intended information. Finally we present a comparative analysis of these data hiding techniques.
FuGeIDS: Fuzzy Genetic paradigms in Intrusion Detection Systems
Rajdeep Borgohain
Computer Science , 2012,
Abstract: With the increase in the number of security threats, Intrusion Detection Systems have evolved as a significant countermeasure against these threats. And as such, the topic of Intrusion Detection Systems has become one of the most prominent research topics in recent years. This paper gives an overview of the Intrusion Detection System and looks at two major machine learning paradigms used in Intrusion Detection System, Genetic Algorithms and Fuzzy Logic and how to apply them for intrusion detection.
Multipath Routing of Fragmented Data Transfer in a Smart Grid Environment
Tuhin Borgohain,Amardeep Borgohain,Rajdeep Borgohain,Sugata Sanyal
Computer Science , 2014, DOI: 10.5120/19528-1165
Abstract: The purpose of this paper is to do a general survey on the existing communication modes inside a smart grid, the existing security loopholes and their countermeasures. Then we suggest a detailed countermeasure, building upon the Jigsaw based secure data transfer [8] for enhanced security of the data flow inside the communication system of a smart grid. The paper has been written without the consideration of any factor of inoperability between the various security techniques inside a smart grid
A Study on Nutritional Status and Dental Caries in Permanent Teeth among School Going Girl of Bengalee Population, India  [PDF]
Madhumati Chatterjee, Arup Ratan Bandyopadhyay
Advances in Anthropology (AA) , 2012, DOI: 10.4236/aa.2012.23013
Abstract: Variations in tooth eruption patterns are supposed to have multifactorial reasons and etiologic factors to explain variation in caries are unsatisfactory. Prevalence of caries is comparatively higher in the children of developing countries than that of the children of same age in developed countries. Indian studies on the dental caries mostly in children related to prevalence and treatment. However, nutritional effect on dental caries on Indian school going children is yet to be carried out in eastern India. This study investigated the prevalence of dental caries in permanent teeth and nutritional status among the 544 School going children (girls) of 6 - 19 years age group of Bengalee ethnicity of West Bengal, India. Caries was recorded based on DMFT index following basic guidelines for Oral Health Surveys guideline (WHO). Nutritional status was obtained using BMI and classification of nutritional status was achieved using the standards of WHO and CDC growth charts include an age- and sex-specific BMI reference for children aged 2 - 20 year. The overall prevalence of dental caries was 44.5% and mean DMFT was 0.45 ? 1.57. Nutritional status demonstrated, about 30% and 6.69% of schools going girls were underweight and overweight respectively. Occurrence of dental caries was found in all permanent teeth among the girls of underweight and normal according to their BMI-for age status. Furthermore, a significant association (p < 0.05) with occurrence of dental caries among the underweight girls has been found compared to that of the overweight and normal. This study indicates a close relationship between nutritional status and dental caries in this region.
Construction of Exactly Solvable Ring-Shaped Potentials  [PDF]
Arup Bharali, Ngangkham Nimai Singh
Journal of Modern Physics (JMP) , 2013, DOI: 10.4236/jmp.2013.44065

We propose a method for construction of exactly solvable ring-shaped potentials where the linear homogeneous second-order differential equation satisfied by special function is subjected to the extended transformation comprising a coordinate transformation and a functional transformation to retrieve the standard Schr?dinger polar angle equation form in non-relativistic quantum mechanics. By invoking plausible ansatze, exactly solvable ring-shaped potentials and corresponding angular wave functions are constructed. The method is illustrated using Jacobi and hypergeometric polynomials and the wave functions for the constructed ring-shaped potentials are normalized.

Weighted Fractional Differentiation Composition Operators from Mixed-Norm Spaces to Weighted-Type Spaces
D. Borgohain,S. Naik
International Journal of Analysis , 2014, DOI: 10.1155/2014/301709
Abstract: Let be an open unit disc in the complex plane and let as well as be analytic maps. For an analytic function on the weighted fractional differentiation composition operator is defined as , where , , and . In this paper, we obtain a characterization of boundedness and compactness of weighted fractional differentiation composition operator from mixed-norm space to weighted-type space . 1. Introduction The classical/Gaussian hypergeometric series is defined by the power series expansion Here , , are complex numbers such that , , and is Pochhammer’s symbol/shifted factorial defined by Appel’s symbol and for . Obviously, . Many properties of the hypergeometric series including the Gauss and Euler transformations are found in standard textbooks such as [1, 2]. For any two analytic functions and represented by their power series expansion, in , the Hadamard product (or convolution) of and denoted by and is defined by in . Moreover, In particular, if , we have If and , then the fractional derivative (see [3]) of order is defined by In terms of convolution, we also have For , we define It is obvious to find that the fractional derivative and the ordinary derivative satisfy Let be fixed and let?? be nonconstant analytic self-map of . For and , we can define an operator on , called a weighted fractional differentiation composition operator, by We can regard this operator as a generalization of a multiplication operator and a weighted composition operator. In this paper we study the boundedness and the compactness of weighted fractional differentiation composition operator from mixed-norm spaces to weighted-type spaces. Recall that a positive continuous function on is called normal if there is and and with such that Let be the normalized Lebesgue area measure on and let??? be the space of all analytic functions on . For , , and is normal we denote by the space of all functions such that where and where When and , , then (classical weighted Bergman space), defined by Further, when then the natural limit to the weighted Bergman space is the Hardy space ; that is, . For more details on Hardy space, see [4]. Suppose is normal and radial; that is, . The weighted-type space consists of all such that A little version of is denoted by as the subset of consisting of all such that Note that is a closed subspace of . For the space , see [5]. For , we have the space of bounded analytic functions , where For ,?? equals the weighted composition operator defined by , , which reduces to the composition operator for . During the last century, composition operators were studied
Some new lacunary $f$-statistical $A$-convergent sequence spaces of order $α$
Ekrem Savas,Stuti Borgohain
Mathematics , 2015, DOI: 10.1063/1.4930512
Abstract: We study the concept of density for sets of natural numbers in some lacunary $A$-convergent sequence spaces. Also we are trying to investigate some relation between the ordinary convergence and module statistical convergence for evey unbounded modulus function. Morever we also study some results on the newly defined lacunary $f$-statistically $A$-convergent sequence spaces with respect to some Musielak-Orlicz function.
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