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Item Transformer-less Solar Photovoltaic Gird Connected Inverter(Indian Patent Office, Chennai, 2020-04-17) National Institute of Technology Karnataka, SurathkalItem Antecedents of satisfaction with teamwork in higher education: An empirical study(2021) Kumar S.P.Developing a theoretical framework to understand undergraduate student teamwork dynamics has always been a topic of interest for educational researchers. Essentially, this is because teamwork is seen as a method for learning and professional development as many companies allocate their work in teams. Hence, there is a need for researchers to look into the underlying factors that can influence teamwork effectiveness among university students. Although there exist a few studies on identifying the antecedents of satisfaction with teamwork, this study intends to analyses the influence of task factors, such as workload, and individual factors, such as collaborative behaviour, on satisfaction with teamwork and expected quality respectively. In addition, the study was also employed to understand the role of team cohesiveness and individuals having knowledge, skills and abilities on satisfaction with teamwork and expected quality respectively. Data were collected from 151 students who are studying their undergraduate course in Indian universities. The proposed causal relationship was examined with SmartPLS 3, as it allows us to analyse multiple causal relationships in a single framework. The findings show that workload has significant negative relationship with both satisfaction with teamwork and team cohesiveness. Whereas, team cohesiveness in turn has a significant positive relationship with satisfaction with teamwork. Similarly, collaborative behaviour has emerged as significant predictor of individual’s knowledge, skills and abilities, and expected quality from a teamwork. In turn, it was identified that individual’s knowledge, skills and abilities could influence both team cohesiveness and expected quality. The findings of the study have implication to both the administrators and teachers involved in designing and deploying the coursework to university students. © 2021, Rajarambapu Institute Of Technology. All rights reserved.Item ANN modeling and residual analysis on screening efficiency of coal in vibrating screen(2021) Shanmugam B.K.; Vardhan H.; Raj M.G.; Kaza M.; Sah R.; Hanumanthappa H.In this paper, coal screening in vibrating screen was carried out with the size ranges of −6 mm + 4 mm, −4 mm + 2 mm, and −2 mm + 0.5 mm. The vibrating screen was newly designed with flexibility in angle and frequency. The vibrating screen experimentation was carried out by varying screen mesh, angle, and screen frequency. During the screening, the angle was kept constant, and frequency was varied to obtain each size range’s screening efficiency. The experimental results of screening efficiency were evaluated for each size fraction range of coal. The maximum efficiency for screening coal with −6 mm+4 mm, −4 mm+2 mm, and −2 mm+0.5 mm size range obtained was 87.60%, 80.93%, and 62.96%, respectively. Further, the prediction model was developed for each size range using a feed-backward artificial neural network (ANN) to consider the back-propagation error technique. For each screening condition, 10 ANN models were developed with the variation in 1–10 different neurons. ANN has provided mathematical models with a 99.9% regression coefficient for predicting each size range’s screening efficiency. Furthermore, the residuals of each optimal ANN model were analyzed using a normal probability plot and histogram. The ANN model’s accuracy was obtained from the residual analysis by evaluating four different model conditions, i.e., independence, homoscedasticity, normality, and mean error. © 2021 Taylor & Francis Group, LLC.Item Anharmonicities in the temperature-dependent bending rigidity of BC3 monolayer(2020) Mrudul M.S.; Thomas S.; Ajith K.M.The present work investigated the temperature-dependent thermodynamic and structural characteristics of graphene-like monolayer boron carbide (g-BC3) using classical molecular dynamics simulations. Herein, we mainly focused on the temperature dependence of mean square displacement of thermally stimulated ripples and bending rigidity of g-BC3. We observed that at high temperatures, the specific heat capacity at constant volume exhibits a significant increase beyond the limit of Dulong-Petit value due to the presence of anharmonicity in the g-BC3. Besides, the linear thermal expansion coefficient is found to be negative owing to the excitation of low-frequency bending vibrations in the out-of-plane orientation. Studies reveal that the out-of-plane of height fluctuations and bending rigidity are fully dependent on temperature and are described using the continuum theory of membranes. Moreover, the study on the height fluctuation and correlation shows variation from the estimation of the harmonic theory of membranes as a consequence of the anharmonic features of g-BC3. We believe that our study will provide a notable contribution to numerous applications of g-BC3 including nanoelectromechanical (NEMS) devices to become a reality. © 2020 Elsevier LtdItem Application of back propagation algorithms in neural network based identification responses of AISI 316 face milling cryogenic machining technique(2020) M C K.R.; Malghan R.L.; Shettigar A.K.; Rao S.S.; Herbert M.A.The paper explores the potential study of artificial neural network (ANN) for prediction of response surface roughness (Ra) in face milling operation with respect to cryogenic approach. The model of Ra was expressed as the main factor in face milling of spindle speed, feed rate, depth of cut and coolant type. The ANN is trained using four various back propagation algorithms (BPA). The emphasis of the paper is to investigate the performance and the accuracy of the attained results depicts the effectiveness of the trained ANN in identifying the predicted Ra. The incorporated various BPA in predicting the Ra. The performance comparative study is made among statistical (Response Surface Methodology (RSM)) and ANN (BPA–training algorithm) methods. The various incorporated BPA algorithms are Gradient Descent (GD), Scaled Conjugate Gradient Descent (SCGD), Levenberg Marquardt (LM) and Bayesian Neural Network (BNN). Afterwards the best suitable BPA is identified in predicting Ra for AISI 316 in face milling operation using liquid nitrogen (LN2) as cutting fluid. The outperformed BPA is identified based on the attained deviation percentage and time required for the training the network. © 2020, © 2020 Engineers Australia.Item Analysis of M-QAM Modulated Underwater Wireless Optical Communication System for Reconfigurable UOWSNs Employed in River Meets Ocean Scenario(2020) Uppalapati A.; Naik R.P.; Krishnan P.In this paper, the bit error rate (BER) performance of underwater wireless optical communication system employing with M-ary quadrature amplitude modulation is proposed for underwater optical wireless sensor networks (UOWSN) in river meets ocean scenario. The underwater channel degradation effects such as absorption, scattering and oceanic turbulence is taken into account. The oceanic turbulence is modelled by the Gamma-Gamma distribution. The first time, we proposed re-configurable UOWSN for the real time scenario of the river meets the ocean and derived the novel closed form analytical BER expressions of the proposed system over Gamma-Gamma turbulence with attenuation effects. The impact of oceanic turbulence parameters such as the variations of temperature, kinetic energy, viscosity, salinity, link range and the water type of system performance is investigated for river water, mixed water (river and ocean water) and ocean water. The proposed system and the related analysis will be highly useful in UOWSN and the Internet of underwater thing (IoUT) applications. © 1967-2012 IEEE.Item Analytical solution to transient inverse heat conduction problem using Green’s function(2020) Parida R.K.; Madav V.; Hindasageri V.A transient inverse heat conduction problem concerning jet impingement heat transfer has been solved analytically in this paper. Experimentally obtained transient temperature history at the non-impinging face, assumed to be the exposed surface in real practice, is the only input data. Aim of this study is to estimate two unknown thermo-physical parameters—overall heat transfer coefficient and adiabatic wall temperature—at the impinging face simultaneously. The approach of Green’s Function to accommodate both the transient convective boundary conditions and transient radiation heat loss is used to derive the forward model, which is purely an analytical method. Levenberg–Marquardt algorithm, a basic approach to optimisation, is used as a solution procedure to the inverse problem. An in-house computer code using MATLAB (version R2014a) is used for analysis. The method is applied for a case of a methane–air flame impinging on one face of a flat 3-mm-thick stainless steel plate, keeping Reynolds number of the gas mixture 1000 and dimensionless burner tip to impinging plate distance equals to 4, while maintaining the equivalence ratio one. Inclusion of both radiation and convection losses in the Green’s function solution for the forward problem enhances the accuracy in the forward model, thereby increasing the possibility of estimating the parameters with better accuracy. The results are found to be in good agreement with the literature. This methodology is independent of flow and heating conditions, and can be applied even to high-temperature applications. © 2020, Akadémiai Kiadó, Budapest, Hungary.Item Analysis of impact behaviour of sisal-epoxy composites under low velocity regime(2021) Mahesh V.; Nilabh A.; Joladarashi S.; Kulkarni S.M.The present study concentrates on development of conceptual proof for sisal reinforced polymer matrix composite for structural applications subjected to low velocity impact using a finite element (FE) approach. The proposed sisal-epoxy composite of various thicknesses of 3.2 mm, 4 mm and 4.8 mm is subjected to different impact velocities of 1 m/s, 2 m/s and 3 m/s ranging in the low velocity impact regime to study the energy absorbed and damage mitigation behaviour of the proposed composite. The consequence of velocity of impact and thickness of laminate on the sisal epoxy composite's impact behaviour is assessed statistically using Taguchi's experimental design. Outcome of the present study discloses that the energy absorption increases with increased impact velocity and laminate thickness. However, the statistical study shows that impact velocity is predominant factor affecting the impact response of sisal epoxy composite laminate compared to laminate thickness. The role of matrix and fiber in damage initiation is studied using Hashin criteria and it is found that matrix failure is predominant over the fiber failure. © 2021 Lavoisier. All rights reserved.Item A comparative study on enhancer and inhibitor of glycine–nitrate combustion ZnO screen-printed sensor: detection of low concentration ammonia at room temperature(2020) Manjunath G.; Nagaraju P.; Mandal S.We report a comparative study on enhancing and inhibiting the sensing performance of Sr-doped ZnO (Sr0.01 Zn0.99O) and RuO2-activated Sr-doped ZnO heterostructured sensors towards the low concentration (≤ 50 ppm) of ammonia gas at ambient. Sub-microns sized with high specific surface area, high reactive, oxygen-deficient Sr-doped ZnO particles were synthesized at low temperature (196 °C) through facile glycine–nitrate solution combustion synthesis (SCS) method. Porous, adhered screen-printed film of Sr-doped ZnO with optical bandgap (3.22 eV) was dip-coated using 0.02 M RuCl3 aqueous solution to obtain RuO2 activation. Smaller crystallite size and lesser lattice distortion obtained with Sr-doping in ZnO enhance the gas response (S = 71) towards the 50 ppm of ammonia gas at room temperature. RuO2-activated Sr-doped ZnO sensor associated with lesser oxygen vacancies and a lower concentration of chemisorbed oxygen species due to passivation layer and no-spill-over activity of RuO2, which inhibits the gas response from 71 to 3. Sr-doped ZnO-based sensor shows high selectivity towards ammonia against 50 ppm of volatile organic compound (VOCs) vapor. Expeditious sensor kinetics (response time and recovery time) in the Sr-doped ZnO sensor was observed, in which smaller crystallite size offers a shorter distance for the diffusion of oxygen vacancies (Vo). Ultra-high-sensitive and selective sensors with ease and economical fabrication offer feasibility in industries and domestic applications where detection of the less concentration ammonia vapor is crucial. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.Item Analysis of ionic and nonionic surfactants blends used for the reverse micellar extraction of Lactoperoxidase from whey(2021) Karanth S.; Iyyaswami R.Bovine Lactoperoxidase (LP), a minor whey protein, is used as an antimicrobial in cosmetic, food, and pharmaceutical preparations. Industries are in pursuit of reliable, cheap, and scalable purification methods as the conventional techniques for LP purification like chromatography and membrane separation suffer from several drawbacks. The present work investigates the selective reverse micellar extraction of LP using the reverse micellar system formed by mixing food grade nonionic (Tween, Span, and Triton series) and ionic (AOT) surfactant blends. The analysis of LP extraction efficiency was performed by varying the concentration of nonionic surfactants with a constant AOT concentration of 100 mM and the initial pH of the system. Complete LP solubilization was achieved with reverse micelles formed by 100 mM AOT and 20 mM Tween 80 at pH 8. It was found that the extraction efficiency was dependent on the chain length or the number of ethylene oxide units in the Triton surfactant tail and the carbon–carbon double bond in Tween 80 tail, that is, on oleic acid. Span series however showed poor extraction in the organic phase substantiating the lesser water content. The forward extracted LP was successfully back-extracted into a fresh aqueous phase containing 1 M KCl at pH 10.5. The aqueous phase (whey) from the forward transfer can be further used to fractionate other whey proteins. © 2020 Curtin University and John Wiley & Sons, Ltd.