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Students Satisfaction with Remote Learning During the COVID-19 Pandemic: Insights for Policymakers
Purpose: This study aimed to learn more about the factors influencing student happiness and involvement in remote learning in Indian higher education institutions (HEIs). The study aims to assist administrators, strategists, and politicians in efficiently dealing with educations new normal. Methodology: The study used a quantitative research approach to fulfill the research aims. A sample of 546 students from various Indian HEIs was chosen, and data were gathered using standardized questionnaires. Structural equation modeling, confirmatory factor analysis, and importance-performance analysis (IPA) were used to calculate the student satisfaction index and examine the impact of various factors. Findings: The findings of this study revealed that institutional and faculty support emerged as the most influential factor impacting students satisfaction through remote learning. It also highlighted the need for HEIs to redesign the assessment process and evaluation techniques to adapt to the remote learning environment. Practical Implications: The findings of this study indicated the practical consequences for administrators, strategists, and policymakers at Indian HEIs. It was advised that improving institutional and teacher support should be a major concern in order to improve student happiness in remote learning situations. Furthermore, redesigning assessment procedures and evaluation processes may improve learning outcomes and student engagement. Originality: This study contributed to the existing body of knowledge by specifically investigating the factors influencing student satisfaction in remote learning within Indian HEIs. The findings shed light on the unique challenges and opportunities the shift to remote education presented. They offered valuable insights for managing and improving the quality of education during and beyond the pandemic. 2023, Associated Management Consultants Pvt. Ltd.. All rights reserved. -
Studies on air jet erosion behavior of plasma-sprayed Cr2C3 coatings on Al6061 alloy
This study assesses the efficacy of plasma-sprayed Cr2C3 coatings on AA6061 aluminum alloy in reducing erosion at different angles (30, 60, and 90). The experimental setup involved maintaining a distance of 80 mm between the components, feeding the powder at a rate of 55 g/min, and applying a current density of 460 amps. Weight loss measurements and surface morphology analyses were performed using scanning electron and confocal microscopy. The findings suggest that the Cr2C3 coating significantly improves erosion resistance when compared to specimens without any coating. The erosion angle had a significant impact on the performance of the coating. The coating experienced the least weight loss at an angle of 30 (28.45 g), followed by increased losses at angles of 60 (30.34 g) and 90 (34.2 g). These findings emphasize the significance of the impact angle in determining the severity of material removal. 2024 The Authors -
Studies on Parametric Optimization of HVOF-Sprayed Cr2O3 Coatings on Al6061 Alloy
High-velocity oxy-fuel (HVOF) is a widely used thermal spray technique to obtain high density, high bond strength, and improved hardness coatings. In the present work, optimization of HVOF process parameters was carried out using the Taguchi method to minimize porosity and improve microhardness, and bond strength of Cr2O3 coatings. Based on the signal-to-noise ratio and analysis of variance, the significance of each process parameter and optimum parameter combination is obtained. Based on the signal-to-noise ratio, the most significant process parameter affecting porosity and microhardness was standoff distance, while for bond strength, it was powder feed rate. An optimal combination of process parameters for porosity, microhardness, and bond strength was obtained from S/N ratio analysis. For porosity, optimal parameters were standoff distance of 100rpm, powder feed rate of 30g/min, and gun speed of 250mm/s. The optimal process parameters for microhardness were standoff distance of 300rpm, powder feed rate of 50g/min, and gun speed of 200mm/s. Finally, for bond strength, the optimal process parameters were standoff distance of 300rpm, powder feed rate of 50g/min, and gun speed of 250mm/s. Statistical results for porosity, microhardness, and bond strength showed that the difference between the predicted R2 and adjusted R2 values were relatively minimal and close to the one highlighting the fitness of the regression model employed for analysis. Fracture analysis after bond strength test showed combined adhesion/cohesion type failure for the Cr2O3 coatings. 2021, The Indian Institute of Metals - IIM. -
Studies on phase transitions and dielectric properties of biowaste synthesized porous carbon nanoparticlesferroelectric liquid crystal mixture
Ferroelectric liquid crystals(FLCs), an exciting class of liquid crystals(LCs), found potential applications in the display as well as non-display regimes due to their fast response, low driving voltage and nonvolatile memory. The amalgamation of nanoparticles into FLCs has opened up new avenues in the LCs research field by alterations/modification of the existing properties of LCs. In this work, porous carbon nanoparticles (PCNPs) were dispersed into FLC mixture (W206E) and investigated their doping effect on FLCs textural, phase transition temperatures and dielectric studies in planar-aligned cells. Dielectric spectroscopy was carried out in the frequency range of 20 Hz to 10 MHz to explore the frequency as well as the temperature dependent of FLC in the entire SmC* region. The transition temperature of FLC mixture is increased by 4 C in PCNPs doped FLC sample then undoped FLC sample. Nearly 8.42% increase in permittivity is observed. A Gold stone relaxation mode at ?627 Hz was observed at lower frequency. 2024 Taylor & Francis Group, LLC. -
Studies on Photophysical and Biological Activity of Newly Synthesized of 4-Methylpiperidin-4-ol Substituted Pyrazole Derivatives
The in vitro antifungal, antibacterial, and antioxidant activities of a substituted pyrazole derivative (FHM) have been evaluated in the current work. The addition of 4-methylpiperidin-4-ol, which increases the molecules lipid solubility and speeds up absorption by increasing its rate of absorption, gives the molecule strong in vitro antifungal and antibacterial properties. Additionally, it is clear from the findings of structure-activity relationship (SAR) investigations. Additionally, the ab-intio technique was used to theoretically evaluate the photophysical characteristics of produced substances. Using the DFT-B3LYP-6-31G(d) basis set, the ground state optimization and HOMO-LUMO energy levels are computed. Global chemical reactivity and descriptive characteristics are evaluated using theoretically estimated HOMO-LUMO values, and the results demonstrate that the synthesized molecule possesses a high electrophilicity and electronegative index. Overall findings indicate that substituting a 4-methylpiperidin-4-ol substituted pyrazole derivative shows good photophysical and in vitro biological applications. 2024, HARD Publishing Company. All rights reserved. -
Studies on photophysical properties of mono-carbonyl curcumin analogues: Experimental andtheoretical approach
The solvatochromic fluorescence behaviour of mono-carbonyl curcumin analogues has been studied in ten different solvents ranging from non-polar to polar. The solvent effect on the spectral properties of analogues has been discussed. The ground state dipole moments were estimated experimentally by Bilot-Kawski equation which is a function of Stokes shift with the solvent polarity parameters and Guggenheim method and theoretically by TD-DFT studies. The excited state dipole moment was determined using Bilot-Kawski equations. The excited state dipole moments for the two molecules were found to be higher than their corresponding ground state dipole moments. Theoretically Frontier molecular orbital (HOMO/ LUMO) energies were determined by Gaussian 09 W software using TD-DFT. 2018 Oriental Scientific Publishing Company. All rights reserved. -
Studies on sulfur doping and figure of merit in vapor grown Sb2Te3 platelet crystals
A series of p-type Sb2Te3-xSx(x=0, 0.1, 0.2, 0.3 and 0.4) samples for each sulfur composition was vapor deposited to explore the crystal growth mechanism of platelet morphology and to understand their potential use for thermoelectric devices. Structural characterization performed by X-ray diffraction exhibited consistent rhombohedral unit cell parameters for all the antimony telluride crystals with D3d5 space group symmetry. Scanning electron microscopy (SEM) and energy dispersive analysis by X-rays (EDAX) were employed for morphological and compositional studies. The Seebeck coefficient S (?c) of Sb2Te3-xSx crystals for sulfur composition, x=0.3 was remarkably improved, yielding a figure of merit (ZT)=0.54, which is ?2.5 fold rise compared to the melt grown Sb2Te3 crystals. The atomic force microscopic (AFM) imprints revealed that, with increasing content of dopant, distribution of etch pits and microhardness increased in sulfur doped crystals. By optimizing sulfur doping, the antisite (AS) defect formation can be suppressed for enhancing ZT and the results obtained enable to design novel thermoelectric materials for application in power generation and refrigeration. 2015 Elsevier B.V. All rights reserved. -
Studies on sulfur doping and figure of merit in vapor grown Sb2Te3 platelet crystals /
Journal Of Crystal Growth, Vol.412, pp.65-71, ISSN No: 0022-0248. -
Studies on Tensile Properties of Graphene Hydroxyl Reinforced Aluminium 6061 Composites for Vehicle Structures Applications
Aluminium composite plays a significant role in the mechanical structures. Low tensile strength of the aluminium alloy limits its application in mechanical structures. Graphene hydroxyl (GrOH) is a noble emerging material which is an allotropic form of carbon. It has high cohesive strength, good bonding ability with other materials. Carbon bonds processes high compatibility when it reinforced with other material. Reinforcement of GrOH with aluminium composites enhances the wear strength of composite material. This paper focused on analysis of tensile properties and percentage elongation of aluminium composites reinforced with GrOH with various weight percentage (wt. %). The characteristics of aluminium composites, particularly related to its tensile properties are very much important for its use in vehicle structures applications. 2022. MechAero Foundation for Technical Research & Education Excellence. -
Studies on the antifungal activity of biotemplated gold nanoparticles over Candida albicans
Green synthesis and applications of gold nanoparticles are more fascinating research area due to their unique optical properties and high X-ray attenuation power. In this study, we have synthesized gold nanoparticles of uniform size (5 nm) with spherical shape. UVvis spectroscopy, Transmission Electron Microscopy and Atomic Force Microscopy were employed to characterize the synthesized gold nanoparticles. The biomedical applications of the synthesized gold nanoparticles were carried out against most prevalent human fungal pathogen, Candida albicans. Broth micro dilution assay was used to determine minimum inhibitory concentration (MIC). We observed that 0. 5 mM concentration was effective in inhibiting the growth of fungal cells which was later confirmed by spot assay. 2019 Elsevier Ltd -
Studies on the characterisation of thiophene substituted 1,3,4-oxadiazole derivative for the highly selective and sensitive detection of picric acid
A novel thiophene substituted 1,3,4-oxadiazole based chemosensor namely 2-(4-(5-(5-hexylthiophen-2-yl) thiophen-2-yl)phenyl) -5-(5-(5-(5-hexylthiophen-2-yl) thiophen-2-yl)thiophen-2-yl)-1,3,4-oxadiazole [TKO] has been characterised for the efficient detection of picric acid (PA) based on fluorescence quenching mechanism. In this regard, the electronic absorption spectra, fluorescence spectra, and fluorescence lifetime of TKO are recorded in the presence of different nitroaromatic compounds (NACs) in ethanol at room temperature. The absorption studies exhibited a blue shift in the absorption maxima with the increase in the concentration of PA. In the fluorescence titration studies, TKO shows a remarkable fluorescence quenching with picric acid as compared to other nitroaromatic compounds. Using the Benesi-Hildebrand plot, the binding constant value of PA with TKO is determined and is of the order of 6.467 104 M?1. Job's plot analysis confirms the 1:1 binding stoichiometry ratio between TKO and PA and is supported by the 1H NMR studies. The detection limit is determined and is of the order of 10.08 M. The competitive studies revealed that TKO is highly selective for recognizing PA without the interference of other NACs. The theoretical studies were also carried out to understand the binding mechanisms of PA with TKO. The fluorescence quenching of TKO by PA may be attributed to photo induced electron transfer (PET). Overall, the experimental findings suggest that, the novel probe TKO may be used as a highly selective and sensitive chemosensor for the detection of explosives like picric acid. 2022 Elsevier B.V. -
Studies on Uniaxial Compressive Strength of Laterite Masonry Prisms
Vol-04, No.02, April ISNN: 0974-5904 -
Study of 1s internal bremsstrahlung spectrum from 57Co
The internal bremsstrahlung contribution from the electron capture of 57Co has been measured in coincidence with K-X-ray of the residual atom. The end-point energy (EPE) is extracted from the data using the linearised Jauch plot. The transition energy obtained using the (EPE) is 842.7keV, which is close to the value given by Audi and Wapstra. The measured intensity and shape factor from 300 to 600keV are found to be in good agreement with the Glauber and Martin theory. 2002 Elsevier Science Ltd. All rights reserved. -
Study of BrinkmanBard nanofluid convection with idealistic and realistic boundary conditions and by considering the effects of shape of nanoparticles
This study deals with linear and weakly non-linear stability analyses of BrinkmanBard convection in nanoliquid-saturated porous enclosures. Water with a dilute concentration of molybdenum disulfide nanoparticles with 0.06 volume fraction and 30% glass fiber-reinforced polycarbonate as a porous medium with porosity 0.88 are considered to be a working medium. The analytical solution is obtained in the present study for idealistic and realistic boundary conditions, and their results are compared. An analytically intractable Lorenz model with quadratic nonlinearities is reduced to a tractable GinzburgLandau amplitude equation with cubic nonlinearity using the multiscale method. Nanoparticles with different shapesare considered in the study, and their effects on the onset and heat transfer are discussed in great detail graphically in the presence of other parameters arising in the problem. 2021 Wiley Periodicals LLC -
Study of Candidate be Stars in the Magellanic Clouds using near-Infrared Photometry and Optical Spectroscopy
Monthly Notices of the Royal Astronomical Society Vol. 421, Issue 4, pp. 3622-3640, ISSN No. 1365-2966 -
Study of candidate Be stars in the Magellanic Clouds using near-infrared photometry and optical spectroscopy
Mennickent et al. and Sabogal et al. identified a large number of classical Be (CBe) candidates (?3500) in the Large and Small Magellanic Clouds (LMC and SMC) based on their photometric variability using the OGLEII data base. They classified these stars into four different groups based on the appearance of their variability. In order to refine and understand the nature of this large number of stars, we studied the infrared properties of the sample and the spectroscopic properties of a subsample. We cross-correlated the optical sample with the IRSF-MCPS catalogue to obtain the J, H, K s magnitudes of all the four types of stars (?2500) in the LMC and SMC. Spectra of 120 stars belonging to the types 1, 2 and 3 were analysed to study their spectral properties. Among the four types, the type 4 stars are the dominant group, with ?60 and ?65 per cent of the total sample in the LMC and SMC, respectively. The near-infrared (NIR) colour-colour diagrams suggest that the type 4 stars in the LMC have a subclass, which is not found in our Galaxy or in the SMC. This subclass is ?18 per cent of the type 4 sample. The main type 4 sample which is ?49 per cent of the total sample has NIR properties similar to the Galactic CBe stars and the SMC type 4 stars. Though the new subclass of type 4 stars have high E(B-V) ? 0.75, they are not located close to regions with high reddening. The type 3 stars (?6 per cent and 7.3 per cent in the LMC and SMC) are found to have large H? equivalent width (EW) in the SMC and some are found to have large NIR excess. This small fraction of stars are unlikely to be CBe stars. Three stars among the type 3 stars in the LMC are found to be double periodic variables. The type 2 stars are found in larger fraction in the SMC (?14.5 per cent), when compared to the LMC (?6 per cent). The spectroscopic and the NIR properties suggest that these could be CBe stars. The type 1 stars are relatively more in the LMC (?24 per cent) when compared to the SMC (?13 per cent). The SMC type 1 stars have relatively large H? EW and this class has properties similar to CBe stars. The spectroscopic sample of type 1 stars which show H? in emission and are confirmed as CBe stars are more abundant in the SMC by a factor of 2.6. If the effect of metallicity is to cause more CBe stars in the SMC, when compared to the LMC, then type 1, type 2 and type 4 stars follow this rule, with an enhancement of 2.6, 2.4 and 1.3, respectively. 2012 The Authors Monthly Notices of the Royal Astronomical Society 2012 RAS. -
Study of chaos in the Darcy-Bard convection problem with Robin boundary condition on the upper surface
Possibility of chaos is studied in Darcy-Bard convection using the Dirichlet and the Robin boundary condition at the lower and upper boundaries, respectively. Comparison is made with the results of Dirichlet (classical-Darcy-Bard convection, CDBC) and Neumann boundary condition (Barletta-Darcy-Bard convection, BDBC). It is found that the cell size at onset is bigger in the case of BDBC compared to the generalized-Darcy-Bard convection (GDBC) and much bigger compared to CDBC. The critical-Darcy-Rayleigh number of BDBC is found to be the least and that of CDBC is the largest. Nonlinear-stability-analysis is performed leading to the scaled-generalized-Vadasz-Lorenz model (SGVLM). In deriving this model, help is sought from a local-nonlinear-stability-analysis that yields the form of the convective-mode. The SGVLM is shown to be dissipative and conservative, with its bounded solution trapped within an ellipsoid. Onset of chaos and its characteristics are studied using the Hopf-Rayleigh-number, the Lorenz-butterfly-diagram, and the plot of the amplitude of the convective-mode vs the control-parameter, R, which is the eigenvalue. Chaos sets in earlier in CDBC and much later in BDBC when compared to that in GDBC. Beyond the onset of chaos is seen a sequence of chaotic and periodic motions, with the latter sometimes being present for an extended period. 2024 Author(s). -
Study of classical Be stars in open clusters older than 100 Myr
We performed the slitless spectroscopic survey to identify classical Be (CBe) stars in open clusters older than 100 Myr. Observing a sample of 71 open clusters, we identified 13 CBe stars in 11 open clusters, one of, which (TYC 2679-432-1) is a new detection. The 13 CBe stars show both H? in emission and IR excess, which confirm that they possess gaseous circumstellar discs. Two more CBe stars are found to exhibit H? in absorption for the first time, indicating that might be passing through disc-less episode presently. The spectral-type estimation is done for all these 15 stars and it is noticed that they belong to B0.5B8 type. Moreover, we found that the distribution of our sample is peaking near late B-types as expected. 2021, Indian Academy of Sciences. -
Study of correlation between optical flux and polarization variations in BL Lac objects
Polarized radiation from blazars is one key piece of evidence for synchrotron radiation at low energy, which also shows variations. We present here our results on the correlation analysis between optical flux and polarization degree (PD) variations in a sample of 11 BL Lac objects using ?10 yr of data from the Steward Observatory. We carried out the analysis on long-term (?several months) as well as on short-term time-scales (?several days). On long-term time-scales, for about 85 per cent of the observing cycles, we found no correlation between optical flux and PD. On short-term time-scales, we found a total of 58 epochs with a significant correlation between optical flux and PD, where both positive and negative correlation were observed. In addition, we also found a significant correlation between optical flux and ?-ray flux variations on long-term time-scales in 11 per cent of the observing cycles. The observed PD variations in our study cannot be explained by changes in the power-law spectral index of the relativistic electrons in the jets. The shock-in-jet scenario is favoured for the correlation between optical flux and PD, whereas the anticorrelation can be explained by the presence of multizone emission regions. The varying correlated behaviour can also be explained by the enhanced optical flux caused by the newly developed radio knots in the jets and their magnetic field alignment with the large-scale jet magnetic field. 2022 The Author(s). -
Study of Effect of Vipassana on Anxiety and Depression
International Journal of Psychology and Behavioral Sciences, Vol-2 (6), pp. 274-276.