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Nowadays the education system has dramatically changed from traditional classroom teaching to remote online teaching due to the COVID-19 crisis. Many developed countries are adopting this novel technology 'e-Learning' to educate their students. But in the case of developing countries e-Learning is a burdensome process due to so many reasons. This is an academic research to estimate the challenges in e-Learning among various age groups of students studying in various schools, colleges and Universities during the lockdown period due to the COVID-19 crisis. The study was conducted in the southern part of India 'Tamilnadu', employing a questionnaire prepared using 'Google form'. An aggregate of 335 students participated in this survey. Some interesting facts were revealed in this study.

In this investigation, Jatropha methyl ester (JME) [JME 20% (volume) + diesel 80% (volume)] was used to adjust the engine’s compression ratio (CR 16, 17, 17.5, and 18) and fuel injection (IT) in the range of 21–25 deg. crank angle (CA) in steps of 2 deg. before top dead center (BTDC), to identify emission profiles of the engine, where the standard CR and IT were 17.5 and 23 deg. CA BTDC. The results reveal that the CO and UHC were obtained to be as low as 0.03% vol at 75% load, CR18, and IT25, and 5 ppm at full load, CR18, and IT25 respectively. The NOx emission rallied from as low as 47 ppm at no load to as high as 1179 ppm at full load, IT of 25, and CR of 18. Whereas the NOx for diesel was 1108 ppm at full load with standard engine operation. The smoke was about 22.1% with CR18 and IT25 for JME20. However, at standard CR and IT for JME20, the smoke was 34.6%. Elevated CR of 18 and advanced IT of 25 are superior to other conditions, hence it is recommended for JME20-powered engines.Article Highlights: Jatropha seeds used were collected from the Arunachal Pradesh Forest areas of India. Sustainable decentralized power generation from JME was attained. CR of 18 and IT of 25 were superior to that of other engine conditions with JME20. [ABSTRACT FROM AUTHOR]

To augment the heat transfer phenomenon, the infusion of various fin geometry over the heated plate is being investigated by various researchers. Solid fins of the porous medium can enhance the convective heat transfer, providing a higher surface area-to-volume ratio for heat transfer. In this work, the fluid flow pattern and thermodynamic analysis of porous-based split elliptical fins mounted staggered over a heated base plate is numerically studied with the Reynolds numbers in the range of 783 to 1839, which is dependent on the fin dimension. The variable parameters were dimensionless transverse offset ( TO ∗ = transverse offset / diameter), which varied from 0 to 0.5; dimensionless longitudinal offset (L O ∗ = longitudinal offset / diameter), which varied from 0 to 0.25; porosity (ɸ), which varies from 0.8 to 0.92; pores per inch (PPI), which was 10; permeability ( P n ); and inertial parameter (F). To count the viscous and inertial effect inside the porous zone, the Forchheimer–Brinkman extended Darcy model was adopted. The associated parameters, the Nusselt number (Nu), frictional coefficient ( C f ), and performance evaluation criteria (PEC), are thoroughly analyzed over the TO ∗ and LO ∗ combination. The results of the investigation revealed that the highest value of Nu and PEC was obtained by TO ∗ = 0.5 and L O ∗ = 0 at ɸ = 0.92 , which were approximately 54% and 79% higher than the solid circular fin at Re = 1839. Additionally, a response function based on Nu was obtained using the response surface method, and cuckoo optimization was assessed to identify the optimal Nu. The optimal Nu is established at TO ∗ = 0.4141 and L O ∗ = 0 (ɸ = 0.92 and Re = 1839) and was validated with the present investigation with an accuracy of 1.20%. [ABSTRACT FROM AUTHOR]

The corrosion behaviour of the closed-cell aluminium foam made of Al 6101 alloy in different heat regimes such as heat treatment (HT), cryogenic treatment (CT) and cryogenic heat treatment (CHT) are investigated in this research work. The Electrochemical Impedance Spectroscopy (EIS) and DC polarisation are the techniques employed in this research work. The microstructure, surface morphology and composition of the treated foam samples are evaluated using a high-resolution Scanning Electron Microscope (SEM) and Energy Dispersive Analysis of X-rays (EDAX). The polarisation and electrochemical impedance measurements of the CT and HT foam samples reveal appealing results in the corrosion resistance when comparing with untreated foam sample. From the SEM images, it is evident that the deep cryogenic treatment changes the morphology of Al 6101 foam and the formation of the Guinier-Preston (GP) zone increases the density of dislocation. [ABSTRACT FROM AUTHOR]

Nanofluids are generally utilized in providing cooling, lubrication phenomenon, and controlling the thermophysical properties of the working fluid. In this paper, nanoparticles of Al2O3 are added to the base fluid, which flows through the counterflow arrangement in a turbulent flow condition. The fluids employed are ethylbenzene and water, which have differing velocities on both the tube and the shell side of the cylinders. A shell tube-type heat exchanger is used to examine flow characteristics, friction loss, and energy transfer as they pertain to the transmission of thermal energy. The findings of the proposed method showed that the efficiency of a heat exchanger could be significantly improved by the number, direction, and spacing of baffles. With the inclusion of nanoparticles of 1% volume, the flow property, friction property, and heat transfer rate can be considerably improved. As a result, the Nusselt number and Peclet numbers have been increased to 261 and 9.14 E +5. For a mass flow rate of 0.5 kg/sec, the overall heat transfer coefficient has also been increased to a maximum value of 13464. The heat transfer rate of the present investigation with nanoparticle addition is 4.63% higher than the Dittus–Boelter correlation. The friction factor is also decreased by about 17.5% and 11.9% compared to the Gnielinski and Blasius correlation. The value of the friction factor for the present investigation was found to be 0.0376. It is hence revealed that a suitable proportion of nanoparticles along with the base fluids can make remarkable changes in heat transfer and flow behavior of the entire system. [ABSTRACT FROM AUTHOR]

Composite materials have always attracted interest from researchers as well as end-users at the same time, due to its flexibility and low cost. Our present study deals with the possible usage of natural fibres extracted from the banyan tree (Ficus Benghalensis) for engineering applications. Epoxy resin (Araldite LY 556) and anhydride hardener (HY 917) are used as the matrix to fabricate the composite panel. In this research work, 30% of fibre derived from banyan aerial root has been reinforced with 70% of polymer mat to study for its mechanical properties such as tensile strength and flexural strength. The processing of the composite materials is done by hand layup process at room temperature. Later specimens are cut from the prepared composite laminates according to the ASTM 3039 (tensile) and ASTM D790 (flexural) Standards. Finally, the Fractography of the mechanically tested specimens was analysed using FESEM. [ABSTRACT FROM AUTHOR]

In this research work, dimple texture tubes and silicon dioxide (SiO2) nanofluid were used to analyze the performance parameters of a solar water heater. For this purpose, SiO2 was mixed with deionized (DI) water using an ultrasonic dispersion device to prepare the nanofluids (SiO2/DI-H2O). The size of the nanoparticle was in the range of 10-15 nm. Different volume concentrations of the nanoparticles in the range of 0.1% to 0.5%, in steps of 0.1%, were chosen to prepare the nanofluids to carry out the experiments. Apart from this, computational fluid dynamics (CFD) tool was used to numerically analyze the parameters affecting the performance of the solar water heater, as well as the fluid flow pattern in the dimple texture tube. During the experiment, the mass flow rate of the base fluid (water) varied in the range of 0.5 kg/min to 3.0 kg/min in steps of 0.5 kg/min. The added advantage of the dimple texture tube design led to an increase in turbulence in the flow pattern, resulting 34.2% increase in the convective heat transfer efficiency compared with the plain tube. Among all experimental modules, SiO2/DI-H2O with a mass flow rate of 2.5 kg/min and 0.3% volume concentration gives overall optimized results in absolute energy absorption, gradient temperature, and efficiency of the solar water heater. The efficiency metrics of the experimental results were compared with the simulation results, and it was in the acceptable range with an overall deviation of ±7.42%. [ABSTRACT FROM AUTHOR]

This paper elucidates the outcome of machining factors specifically cutting velocity, feed rate and depth of cut on the machining characteristics such as surface roughness and tool-work interface temperature while turning cylindrical AISI 52100 steel alloy components in dry and microlubrication machining conditions. The experiments are designed based on the Taguchi's L25(53) orthogonal array and conducted on an All Geared Lathe, simultaneously the tool-work interface temperature was observed using a K-type tool-work thermocouple and subsequently, a mathematical model was developed for the tool-work interface temperature values through regression analysis. The surface roughness of the turned steel alloy components is deliberated by means of a precise surface roughness apparatus. A prediction model in lieu of average surface roughness is created by means of nonlinear regression examination with the aid of MINITAB software. The most favourable machining settings are recognised by Taguchi's method and verified with a confirmation trial. The results revealed that machining under microlubrication condition exhibited lesser temperature at the tool-work interface and the quality of the machined components also exhibits lesser roughness when compared with components of dry machining condition. [ABSTRACT FROM AUTHOR]