Christ University

About: Christ University is a education organization based out in Bengaluru, India. It is known for research contribution in the topics: Computer science & Convection. The organization has 2267 authors who have published 2715 publications receiving 14575 citations. The organization is also known as: Christ College & Christ University.

Radiative nonlinear 3D flow of ferrofluid with Joule heating, convective condition and Coriolis force

Abstract: Characteristics of heat transport mechanism in three-dimensional ferrofluid flow past a deformed surface subjected to the Coriolis and Lorentz forces are analyzed. The impacts of Joule heating, nonlinear thermal radiation, viscous dissipation and convective condition are also accounted. The carrier fluid (water) is embedded by Fe 3 O 4 nanoparticles. The boundary layer approximations are employed in problem statement. Stretching transformations are utilized to form nonlinear ODE system from governed PDE system. The subsequent system is treated numerically via Runge-Kutta-Fehlberg method. Effects of relevant parameters on different flow fields are discussed comprehensively with help of graphs. It is established that the heat transfer rate is enhanced due to Coriolis and Lorentz forces. Furthermore, Fe 3 O 4 nanoparticles enhance the Nusselt number significantly in comparison with Al 2 O 3 nanoparticles.

Analysis of Membership Probability in Nearby Young Moving Groups with Gaia DR2

Abstract: We analyze the membership probability of young stars belonging to nearby moving groups with $\textit{Gaia}$ DR2 data. The sample of 1429 stars were identified from 'The Catalog of Suspected Nearby Young Moving Group Stars'. Good-quality parallax and proper motion values were retrieved for 890 stars from $\textit{Gaia}$ DR2 database. The analysis for membership probability is performed in the framework of LACEwING algorithm. From the analysis it is confirmed that 279 stars do not belong to any of the known moving groups. We estimated the $\textit{ U, V, W}$ space velocity values for 250 moving group members, which were found to be more accurate than previous values listed in the literature. The velocity ellipses of all the moving groups are well constrained within the "good box", a widely used criterion to identify moving group members. The age of moving group members are uniformly estimated from the analysis of $\textit{Gaia}$ Color-Magnitude Diagram with MIST isochrones. We found a spread in the age distribution of stars belonging to some moving groups, which needs to be understood from further studies.

Cipher Block Chaining Support Vector Machine for Secured Decentralized Cloud Enabled Intelligent IoT Architecture

Abstract: The growth of internet era leads to a major transformation in a storage of data and accessing the applications. One such new trend that promises the endurance is the Cloud computing. Computing resources offered by the Cloud includes the servers, networks, storage, and applications, all as services. With the advent of Cloud, a single application is delivered as a metered service to numerous users, via an Application Programming Interface (API) accessible over the network. The services offered via the Cloud are such as the infrastructure, software, platform, database and web services. The main motivation of this application model is to provide computationally secure key generation to protect the data via encryption. This key generation in the cryptography process falls into three categories in this research work. In the first part, SVM based encryption service model is constructed for which the key generation is from the conventional encryption operation mode with some improvements. To make the process more complex, the optimization techniques are taken into account for the key generation in descendant two methods application model that acts computationally more secure specifically for Cloud environment. The results of security analysis confirm the effectiveness of the proposed application model withstands potentially against various attacks such as Chosen Cipher Attack, Chosen Plain text Attack indistinguishable attacks for files. In case of images, it resists well against statistical and differential attacks. Comparative Analysis shows evidence of the efficiency of the developed pioneering application model quality and strength compared with that of the existing services.

Temporal correlation between the optical and γ-ray flux variations in the blazar 3C 454.3

Abstract: Blazars show optical and $\gamma$-ray flux variations that are generally correlated, although there are exceptions. Here we present anomalous behaviour seen in the blazar 3C 454.3 based on an analysis of quasi-simultaneous data at optical, UV, X-ray and $\gamma$-ray energies, spanning about 9 years from August 2008 to February 2017. We have identified four time intervals (epochs), A, B, D and E, when the source showed large-amplitude optical flares. In epochs A and B the optical and $\gamma$-ray flares are correlated, while in D and E corresponding flares in $\gamma$-rays are weak or absent. In epoch B the degree of optical polarization strongly correlates with changes in optical flux during a short-duration optical flare superimposed on one of long duration. In epoch E the optical flux and degree of polarization are anti-correlated during both the rising and declining phases of the optical flare. We carried out broad-band spectral energy distribution (SED) modeling of the source for the flaring epochs A,B, D and E, and a quiescent epoch, C. Our SED modeling indicates that optical flares with absent or weak corresponding $\gamma$-ray flares in epochs D and E could arise from changes in a combination of parameters, such as the bulk Lorentz factor, magnetic field and electron energy density, or be due to changes in the location of the $\gamma$-ray emitting regions.

Isolation and Characterization of Antidermatophytic Bioactive Molecules from Piper longum L. Leaves

Abstract: Piper longum L. (Piperaceae) commonly known as “long pepper” is a well known medicinal plant in ayurveda. Different parts of this plant, such as root, seed, fruit, whole plant etc. are used traditionally in various ailments. Here we have investigated the antidermatophytic activity of sequentially extracted petroleum ether, chloroform, methanol and water extracts from P. longum leaf against Trichophyton mentagrophytes, T. rubrum, T. tonsurans, Microsporum fulvum and M. gypseum. Better activity of chloroform and methanol extracts was observed. The chloroform extract was selected for further study and the MIC value was recorded as 5.0 mg ml−1 against the test organisms. In the chloroform extract, tannins and phenolic compounds were detected. Further activity-guided fractionation of chloroform extract by silica gel column chromatography yielded nine major fractions. Among these, fraction-1, 4, 5 and 7 showed higher antidermatophytic activity. Fraction-4 on further purification by repeated column chromatography yielded a potential antidermatophytic fraction showing MIC value of 0.625 mg ml−1 against T. mentagrophytes and T. rubrum as determined by broth microdilution method. The major compounds were identified as 1,2-benzenedicarboxylic acid, bis(2-ethylhexyl) ester (C24H38O4] (41.45 %), 2,2-dimethoxybutane (C6H14O2] (13.6 %) and β-myrcene (C10H16) (6.75 %) based on GC–MS data.