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Hybrid nanofluid flow over a vertical rotating plate in the presence of hall current, nonlinear convection and heat absorption
An exact analysis has been carried out to study a problem of the nonlinear convective flow of hybrid nanoliquids over a vertical rotating plate with Hall current and heat absorption. Three different fluids namely CuAl2O3H2Ohybrid nanofluid, Al2O3H2O nanofluid and H2O basefluids are considered in the analysis. The simulation of the flow was carried out using the appropriate values of the empirical shape factor for five different particle shapes (i.e., sphere, hexahedron, tetrahedron, column and lamina). The governing PDEs with the corresponding boundary conditions are non-dimensionalised with the appropriate dimensionless variables and solved analytically by using LTM (Laplace transform technique). This investigation discusses the effects of governing parameters on velocity and temperature fields in addition to the rate of heat transfer. The numeric data of the density, thermal conductivity, dynamic viscosity, specific heat, Prandtl number and Nusselt number for twelve different hybrid nanofluids at 300 K is presented. The temperature profile of hybrid nanoliquid is larger than nanoliquid for same volume fraction of nanoparticles. Also, the glycerin-based nanoliquid has a high rate of heat transfer than engine oil, ethylene glycol and water-based nanoliquids in order. 2018 by American Scientific Publishers All rights reserved. -
Prevalence of hypertension and determination of its risk factors in korangrapady, udupi district, coastal Karnataka, India
Objective: Hypertension is a global public health problem that estimates about 4.5% of overall disease burden. It is a general health challenge in economically developing and developed countries. High blood pressure prevalence is increased from 11.2% to 28% (p<0.001) and 2342.2% in rural and urban area according to the study done in Delhi for about 20 years. It is one of the important risk factors of cardiovascular disease, which is associated with morbidity and mortality. The aim was to identify the significant correlates of hypertension in a rural village in south India. Methods: Data were collected through a door-to-door survey among the residents of the village. Data collected was related to demographics and anthropometric measures. Blood pressure was measured with the help of the medical supervisor. Data were analyzed using Chi-square test for comparison between attributes. The potential hazard factor of hypertension was found by performing binary logistic regression model. Result: Of 299 participants considered for the study, 50 were hypertensive contributing to the overall prevalence of 16.72% with 95% confidence interval of 0.12920.2137, in which females have the prevalence rate of 17.8% and males with the prevalence rate of 15.5%. The study outcome identified education level, occupation, and family history of hypertension is the predicted risk factors. Conclusion: The high blood pressure prevalence is low and comparable with the studies conducted in other rural regions of India. More studies are, however, required to decide the appropriation and determinants of hypertension in different parts of this region. 2018 The Authors. -
Properties and Occurrence Rates for Kepler Exoplanet Candidates as a Function of Host Star Metallicity from the DR25 Catalog
Correlations between the occurrence rate of exoplanets and their host star properties provide important clues about the planet formation process. We studied the dependence of the observed properties of exoplanets (radius, mass, and orbital period) as a function of their host star metallicity. We analyzed the planetary radii and orbital periods of over 2800 Kepler candidates from the latest Kepler data release, DR25 (Q1-Q17), with revised planetary radii based on Gaia DR2 as a function of host star metallicity (from the Q1-Q17 (DR25) stellar and planet catalog). With a much larger sample and improved radius measurements, we are able to reconfirm previous results in the literature. We show that the average metallicity of the host star increases as the radius of the planet increases. We demonstrate this by first calculating the average host star metallicity for different radius bins and then supplementing these results by calculating the occurrence rate as a function of planetary radius and host star metallicity. We find a similar trend between host star metallicity and planet mass: the average host star metallicity increases with increasing planet mass. This trend, however, reverses for masses >4.0 M J: host star metallicity drops with increasing planetary mass. We further examined the correlation between the host star metallicity and the orbital period of the planet. We find that for planets with orbital periods less than 10 days, the average metallicity of the host star is higher than that for planets with periods greater than 10 days. 2018. The American Astronomical Society. All rights reserved. -
Magnetohydrodynamic three-dimensional flow of nanofluids with slip and thermal radiation over a nonlinear stretching sheet: a numerical study
A numerical simulation for mixed convective three-dimensional slip flow of water-based nanofluids with temperature jump boundary condition is presented. The flow is caused by nonlinear stretching surface. Conservation of energy equation involves the radiation heat flux term. Applied transverse magnetic effect of variable kind is also incorporated. Suitable nonlinear similarity transformations are used to reduce the governing equations into a set of self-similar equations. The subsequent equations are solved numerically by using shooting method. The solutions for the velocity and temperature distributions are computed for several values of flow pertinent parameters. Further, the numerical values for skin-friction coefficients and Nusselt number in respect of different nanoparticles are tabulated. A comparison between our numerical and already existing results has also been made. It is found that the velocity and thermal slip boundary condition showed a significant effect on momentum and thermal boundary layer thickness at the wall. The presence of nanoparticles stabilizes the thermal boundary layer growth. 2016, The Natural Computing Applications Forum. -
Measurement of financial inclusion status of India
Financial inclusion provides access to formal financial system for all members of the society. Financial inclusion leads to inclusive financial system which has several merits. Financial inclusion facilitates rational allocation of productive resources and thus can potentially reduce the cost of capital. Efforts towards financial inclusion have been undertaken in India for several years. These financial inclusion initiatives have yielded fruitful results for the people to access and use formal financial system. Further, these initiatives led to better penetration of banking system, credit penetration and savings penetration. However, financial exclusion is common phenomena in India among poor and weaker sections. This article has made an attempt to measure state of financial inclusion in India using access indicators, usage indicators and quality indicators of financial inclusion. IAEME Publication. -
Mental health professionals view on the need for early intervention for offspring of individual with schizophrenia in India
Schizophrenia is a debilitating mental illness not only for the individual but also for the family, especially the children. There is a definitive likelihood of the vulnerability being transmitted to the child. As a result of the parents illness there may also be disruptions in the family dynamics and in home environment. However, many children have been found to show resiliency. The aim of this particular study was to explore the need for intervention in children who's either parent were being treated for schizophrenia. Using qualitative Interpretative Phenomenological Approach (IPA) mental health professionals from all over India were interviewed with the help of validated interview guide. To understand their lived in experience of these professionals the audio recorded interviews were transcribed and analysed for exploring the themes using thematic analysis. Significant themes found indicated that early interventions were crucial for the wellbeing of the child, specifically in the Indian scenario. 2018 Oriental Scientific Publishing Company. -
Exact solutions for unsteady mixed convection flow of nanoliquid with exponential heat source: Bruggeman and batchelor nanofluid model
The objective of this paper is to explore the influence of exponential heat source and radiative heat on the thermal and mass transport of nanofluid flow over a vertical sheet. Unlike traditional nanofluid models, the Bruggeman and Batchelor models are utilized to estimate the thermal conductivity and dynamic viscosity of the nanofluid. The water-based copper nanoliquid is considered. Mass flux boundary condition is employed. The governed differential problem is solved by Laplace Transform Method (LTM) for exact solutions. The impact of dimensionless sundry parameters on flow distributions is analyzed and bestowed graphically. The rate of heat transfer has been assessed. Also, the slope of the linear regression line through data points is determined in order to quantify increase/decrease in the Nusselt number. Results exhibited that all the flow fields (velocity and temperature) are increasing functions of thermal and solutal Grashof numbers. Also, the presence of exponential heat source highly affects the heat transfer performance. 2018 by American Scientific Publishers All rights reserved. -
Nonlinear optical studies of sodium borate glasses embedded with gold nanoparticles
Optical glasses possessing large third-order optical nonlinear susceptibility and fast response times are promising materials for the development of advanced nonlinear photonic devices. In this context, gold nanoparticle (NP)-doped borate glasses were synthesized via the melt-quench method. The nonlinear optical (NLO) properties of thus prepared glasses were investigated at different wavelengths (i.e., at 532nm using nanosecond pulses, at 750nm, 800nm, and 850nm wavelengths using femtosecond, MHz pulses). At 532nm, open aperture (OA) Z-scan signatures of gold NP-doped borate glasses demonstrated reverse saturable absorption (RSA), attributed to mixed intra-band and interband transitions, while in the 750?850nm region, the OA Z-scan data revealed the presence of saturable absorption (SA), possibly due to intra-band transitions. The NLO coefficients were evaluated at all the spectral regions and further compared with some of the recently reported glasses. The magnitudes of obtained NLO coefficients clearly demonstrate that the investigated glasses are potential materials for photonic device applications. 2018, Springer-Verlag GmbH Germany, part of Springer Nature. -
Nonlinear radiated MHD flow of nanoliquids due to a rotating disk with irregular heat source and heat flux condition
This research is made to visualize the nonlinear radiated flow of hydromagnetic nano-fluid induced due to rotation of the disk. The considered nano-fluid is a mixture of water and Ti6Al4V or AA7072 nano-particles. The various shapes of nanoparticles like lamina, column, sphere, tetrahedron and hexahedron are chosen in the analysis. The irregular heat source and nonlinear radiative terms are accounted in the law of energy. We used the heat flux condition instead of constant surface temperature condition. Heat flux condition is more relativistic and according to physical nature of the problem. The problem is made dimensionless with the help of suitable similarity constraints. The Runge-Kutta-Fehlberg scheme is adopted to find the numerical solutions of governing nonlinear ordinary differential systems. The solutions are plotted by considering the various values of emerging physical constraints. The effects of various shapes of nanoparticles are drawn and discussed. 2018 Elsevier B.V. -
Significance of Darcy-Forchheimer Porous Medium in Nanofluid Through Carbon Nanotubes
This article manages Darcy-Forchheimer 3D flow of water based carbon nanomaterial (CNTs). A bidirectional nonlinear stretchable surface has been utilized to make the flow. Disturbance in permeable space has been represented by Darcy Forchheimer (DF) expression. Heat transfer mechanism is explored through convective heating. Outcomes for SWCNT and MWCNT have been displayed and compared. The reduction of partial differential framework into nonlinear common differential framework is made through reasonable variables. Optimal series scheme is utilized for arrangements advancement of associated flow issue. Optimal homotopic solution expressions for velocities and temperature are studied through graphs by considering various estimations of physical variables. Moreover surface drag coefficients and heat transfer rate are analyzed through plots. 2018 Chinese Physical Society and IOP Publishing Ltd. -
Brinkman-Forchheimer flow of SWCNT and MWCNT magneto-nanoliquids in a microchannel with multiple slips and Joule heating aspects
Purpose: The microfluidics has a wide range of applications, such as micro heat exchanger, micropumps, micromixers, cooling systems for microelectronic devices, fuel cells and microturbines. However, the enhancement of thermal energy is one of the challenges in these applications. Therefore, the purpose of this paper is to enhance heat transfer in a microchannel flow by utilizing carbon nanotubes (CNTs). MHD Brinkman-Forchheimer flow in a planar microchannel with multiple slips is considered. Aspects of viscous and Joule heating are also deployed. The consequences are presented in two different carbon nanofluids. Design/methodology/approach: The governing equations are modeled with the help of conservation equations of flow and energy under the steady-state situation. The governing equations are non-dimensionalized through dimensionless variables. The dimensionless expressions are treated via Runge-Kutta-Fehlberg-based shooting scheme. Pertinent results of velocity, skin friction coefficient, temperature and Nusselt number for assorted values of physical parameters are comprehensively discussed. Also, a closed-form solution is obtained for momentum equation for a particular case. Numerical results agree perfectly with the analytical results. Findings: It is established that multiple slip effect is favorable for velocity and temperature fields. The velocity field of multi-walled carbon nanotubes (MWCNTs) nanofluid is lower than single-walled carbon nanotubes (SWCNTs)-nanofluid, while thermal field, Nusselt number and drag force are higher in the case of MWCNT-nanofluid than SWCNT-nanofluid. The impact of nanotubes (SWCNTs and MWCNTs) is constructive for thermal boundary layer growth. Practical implications: This study may provide useful information to improve the thermal management of microelectromechanical systems. Originality/value: The effects of CNTs in microchannel flow by utilizing viscous dissipation and Joule heating are first time investigated. The results for SWCNTs and MWCNTs have been compared. 2018, Emerald Publishing Limited. -
Enhancements to greedy web proxy caching algorithms using data mining method and weight assignment policy
A Web proxy caching system is an intermediary between the users and servers that tries to alleviate the loads on the servers by caching selective Web objects and behaves as the proxy for the server and service the requests that are made to the servers by the users. In this paper the performance of a proxy system is measured by the number of hits at the proxy. A higher number of hits at the proxy server reflects the effectiveness of the proxy system. The number of hits is determined by the replacement policies chosen by the proxy systems. Traditional replacement policies that are based on time and size are reactive and do not consider the events that will possibly happen in the future. The outcomes of the paper are proactive strategies that augment the traditional replacement policies with data mining techniques. In this paper, the performances of the greedy replacement policies such as GDS, GDSF and GD* are adapted by the data mining method and weight assignment policy. Experiments were conducted on various data sets. Hit ratio and byte hit ratio were chosen as parameters for performance. 2018 ISSN. -
Effect of multiwalled carbon nanotube alignment on the tensile fatigue behavior of nanocomposites
The one-dimensional structure of carbon nanotubes makes them highly anisotropic, making them to possess unusual mechanical properties, and hence employed as promising nanofiller for the composite structures. However, various carbon nanotube properties are not completely utilized when they are used as reinforcement in composites due to inadequate and immature processing techniques. In the present work, an attempt has been made to utilize the strong anisotropic nature of multi-walled carbon nanotubes (MWCNTs) for improving the fatigue life of nanocomposites only by considering a very low weight percentage (<0.5 wt%). The anisotropy of MWCNTs was imparted into the nanocomposites by aligning them in the epoxy matrix with DC electric field during composite curing. Nanocomposites were made for three MWCNT loadings (0.1, 0.2, and 0.3 wt%). The tensile fatigue behavior was investigated under stress control by applying cyclic sinusoidal load with the frequency range of 13 Hz and stress ratio, R = 0.1. The specimens were tested for the fatigue load until the failure or 1E+05 cycles. The fractured surfaces were examined through scanning electron microscope to analyze the fatigue fracture behavior. A small weight percentage of MWCNT loading (0.2 wt%) into the polymer composite has enhanced on an average 13% to 15% fatigue life, which is encouraging to develop the low cost, improved fatigue life composite structures. Also, the energy dissipation mechanism in MWCNT dispersed nanocomposites has shown a reduced crack propagation rate. The Author(s) 2017. -
Effect of vacancies on thermopower of molybdenum disulfide monolayers
A detailed theoretical investigation of the effect of scattering of electrons and phonons by lattice vacancies in molybdenum disulfide (MoS2) monolayers (MLs) on diffusion, S d, and phonon-drag, S g, components of thermoelectric power (TEP), S, is presented over a wide-temperature range (1 < T < 300 K) using the Boltzmann transport formalism. The diffusion component is assumed to be influenced, not only by vacancies via short-range and Coulomb disorder scattering, but also by charged impurities (CIs) and acoustic and optical phonons. In the case of S g, the phonons are considered to be scattered, besides the vacancies, by sample boundaries, substitutional isotopic impurities, as well as other phonons via both N- and U-processes. Numerical calculations of S d and S g, as functions of temperature and vacancy defect density are presented for MoS2 MLs with n s = 1017 m-2 supported on SiO2/Si substrates. The role of carrier scatterings by mono-sulfur and mono-molybdenum vacancies in influencing the overall electron and phonon relaxation rates and in determining S d and S g are investigated. The behavior of S d and S g is found to be noticeably influenced by vacancy scattering. The influence on S d is seen to be more for mono-sulfur vacancies for densities lesser than 1%. The influence, is to enhance S d slightly for MLs with realizable CI concentrations. On the other hand, S g is found to depend sensitively on the vacancy disorder for T < 50 K; a S-vacancy density of 0.1% is found to suppress the characteristic peak of S g by almost 60%. The extent of reduction in the characteristic peak of S g, observable in low temperature measurements of S, can provide information about defect density. The calculations demonstrate that defect engineering of MoS2 ML systems can be used to tune their thermoelectric performance. A need for detailed experimental studies is suggested. 2018 IOP Publishing Ltd. -
On the Motion of Non-Newtonian EyringPowell Fluid Conveying Tiny Gold Particles Due to Generalized Surface Slip Velocity and Buoyancy
In the painting industry, space science and biomedical science, the nature of relaxation in the flow of non-Newtonian fluid (i.e. blood) containing gold (Ag) suits the characteristics of EyringPowell fluid flow induced by generalized surface slip velocity and buoyancy. However, flow of various non-Newtonian fluids on the horizontal surface of a slanted paraboloid of revolution objects (i.e. rocket, as in space science), over a bonnet of a car and over a pointed surface of an aircraft is of importance to experts in all these fields. In this article, the analysis of the motion within the thin layer formed on a horizontal object which is neither a perfect horizontal nor vertical and neither an inclined surface nor a cone/wedge is presented. The transformed governing equations which model the flow was non-dimenzionalized, parameterized and solved numerically using a well-known RungeKutta integration procedure along with shooting technique. The influence of increasing the magnitude of major parameters on the temperature distribution, local heat transfer rate, concentration of the fluid, local skin friction coefficient and velocity of the flow are illustrated graphically and discussed. Velocity slip parameter is found to be a decreasing function of temperature distribution across the flow. Heat transfer rate (NuxRex-1/2) at the wall (?= 0) is an increasing function of velocity slip parameter. Maximum coefficient of concentration of homogeneous bulk fluid at the wall exists at larger values of the emerged velocity slip and volume fraction parameters. 2018, Springer Nature India Private Limited. -
Performance Analysis of Novel Compact Octagonal Shaped Fractal Antenna for Broadband Wireless Applications
Antenna plays an important role in any part of the communication system. It has to be designed very cautiously to provide improved system performance to meet the developments in wireless technologies with various design constraints such as small size, low cost, high data, low power consumption and wideband capabilities. Several efforts have been made by various investigators around the globe to amalgamate benefits of fractal structures with electromagnetic concepts and applications to reduce the size of the antenna without obstructing the performance of the antennas. This paper proposes a novel compact octagonal shaped broadband fractal antenna. The proposed antenna was designed on an inexpensive FR4-epoxy substrate and simulated using the High Frequency Structure Simulator. The antenna resonates in dual bands in 3.8 and 1GHz with lowest return loss of ?32.80dB and gain of 10.22dB while maintaining the VSWR in the 2:1 level. Attempts have been made to reduce the size and improve the bandwidth using fractal concept and truncation of ground plane. The fabricated antenna was verified experimentally and the results are agreeing with the simulations. The point of attraction of this antenna is the use of single patch for broadband coverage with easy fabrication. 2018, Springer Science+Business Media, LLC, part of Springer Nature. -
Template-based classification of SDSS-GALEX point sources
We have classified a sample of 37,492 objects from SDSS into QSOs, galaxies and stars using photometric data over five wave bands (u, g, r, i and z) and UV GALEX data over two wave bands (near-UV and far-UV) based on a template fitting method. The advantage of this method of classification is that it does not require any spectroscopic data and hence the objects for which spectroscopic data is not available can also be studied using this technique. In this study, we have found that our method is consistent by spectroscopic methods given that their UV information is available. Our study shows that the UV colours are especially important for separating quasars and stars, as well as spiral and starburst galaxies. Thus it is evident that the UV bands play a crucial role in the classification and characterization of astronomical objects that emit over a wide range of wavelengths, but especially for those that are bright at UV. We have achieved the efficiency of 89% for the QSOs, 63% for the galaxies and 84% for the stars. This classification is also found to be in agreement with the emission line diagnostic diagrams. 2018, Indian Academy of Sciences. -
A study on optimal portfolio construction with special reference to NSE CNX Nifty pharma index
Portfolio is a process of blending together the broad asset classes so as to obtain optimum return with minimum risk is called portfolio construction. In order to reduce the risk, investors need to diversify, spread their portfolio across a broad mix of assets. Diversifying the portfolio can help smooth out market ups and downs and returns from better performing assets help to offset those that arent performing so well. The present study has empirically examined the portfolio construction with special reference to NSE CNX Nifty Pharma Index. The study applied the Sharpe Single Index model to generate an efficient combination of securities from sample Pharma companies and has come up with a subsequent pattern. The study found that out the sample Pharma companies, Aurobindo Pharma Ltd attracted high risk while Glenmark Pharmaceuticals Ltd experienced the least risk, on the basis of return earned by the companies in the Pharma Index; Aurobindo Pharma Ltd has high return while Lupin Ltd has lowest return. Experimental results have demonstrated the feasible of the investment strategy, portfolio idea and electiveness of the combination assets on the investment strategy. IAEME Publication. -
Transformation of hydrocarbon soot to graphenic carbon nanostructures
Graphenic carbon nanostructures were synthesized from different precursors of petroleum and agricultural origin by oxidative scissoring. In the present study soot, an environmental pollutant is converted to a value-added product by facile synthesis techniques. The physicochemical changes of the nanostructures are investigated by means of XRD, AFM, FTIR, Raman spectroscopy, XPS analyses SEM-EDS and TEM analysis. XRD analysis confirms the formation of few layer oxidized carbon nanostructures with smaller lateral dimensions. Raman spectra reveal the existence of graphenic layer with a fewer defect. AFM and SEM analyses reveal the formation of stacked tiny fragments of graphenic carbon lamellae. XPS and IR analyses confirm the incorporation of oxygen functionalities into the carbon backbone. 2018 by the authors. -
What is beautiful is good: An evalutation of effectiveness of attractiveness in celebrity endorsements
The studies in the field of marketing have shown that characteristics of the source will influence persuasiveness of an advertisement. Attractiveness is one such celebrity characteristic that is widely studied by researchers in the field of marketing. However, still, literature failed to explain how attractiveness of celebrity endorsers influenced purchase intentions. This study tried to fill this gap by modelling the influence of celebrity attractiveness on purchase intention. It also evaluated the effect of respondents' gender on the model. The data collection for the study were carried out during March - June 2017. The study found that the effect of celebrity attractiveness on purchase intention was mediated by celebrity brand fit, attitude towards the advertisement, and attitude towards the brand. The study also evaluated the moderating effect of respondents' gender using chi- square analysis, which found no significant model difference among male and female respondents. These findings indicated that celebrity attractiveness created purchase intention in a mediated manner among the respondents, irrespective of their gender. 2018, Associated Management Consultants Private Limited.