Browse Items (11810 total)
Sort by:
-
The dark side of technology-enabled teaching: Impact of technostress on student performance
This study validates an instrument used to measure technostress creators, technostress support mechanisms, and their negative impact on students' satisfaction and performance. A research model is developed based on the stimulus, organism, and response model to analyse the mediating effect of technostress creators and understand how technostress inhibitors influence students' satisfaction and their performance. A group of 206 students from India pursuing higher education were selected as a sample to validate this model. Technostress creators act as a mediator between technostress inhibitors and students' satisfaction and their performance, while technostress inhibitors positively influence student satisfaction and performance indirectly. Insights from this study will enable higher education institutions to identify the students who are finding technology-based education problematic and help preserve their wellbeing by following supportive strategies to reduce stress and enhance the students' active participation in technology-based education. Copyright 2021, IGI Global. -
Total induced vertex stress in barbell-like graphs
This paper introduces new parameters called induced vertex stress and total induced vertex stress in G, respectively. For graphs G and H, aspects of the maximum and minimum total induced vertex stress that can be obtained by 1-edge addition and 2-vertex merging are discussed. 2021 Journal of the Indonesian Mathematical Society. All rights reserved. -
Rainbow degree-jump coloring of graphs
In this paper, we introduce a new notion called the rainbow degree-jump coloring of a graph. For a vertex v ? V(G), let the degree-jump closed neighbourhood of this vertex be defined as Ndeg [v] = {u: d(v, u) ? d(v)}. A proper coloring of a graph G is said to be a rainbow degree-jump coloring of G if for all v in V(G), c(Ndeg [v]) contains at least one of each color class. We determine a necessary and sufficient condition for a graph G to permit a rainbow degree-jump coloring. We also determine the rainbow degree-jump chromatic number, denoted by ?rdj (G), for certain classes of cycle related graphs. Mphako-Banda E.G., Kok J., Naduvath S., 2021. -
Plant disease diagnosis and solution system based on neural networks
Plant diseases are one of the major factors affecting crop yield. Early identification of these diseases can improve productivity and save money and time for the farmer. This paper presents a novel technique to diagnose plant diseases using a mobile application. A Convolutional Neural Network (CNN) model was built and trained using MobileNetV2 architecture with the help of image processing techniques and transfer learning. A dataset comprising 87,000 images that contain 38 classes of diseases belonging to 14 different crops was used to train the model. The model achieved an accuracy of 98.69% and a loss of 0.5373. A mobile application was built in Android Studio with the help of a trained model. The mobile application built works without a need for a remote server. The application can identify the disease, gives information regarding the identified disease and also suggests necessary remedies to tackle the disease. 2021, Engg Journals Publications. All rights reserved. -
Legal conundrums of space tourism
Private commercial space tourism carrying passengers to outer space is no longer a distant or far-fetched fantasy, rather it is at verge of becoming an affordable reality with exponential development in space technology including development of Reusable Launch Vehicle (RLV), increasing involvement of private companies like Virgin Galactic, SpaceX, Blue Origin etc. into research and funding of space tourism explorations and applications. It is also receiving huge attention from the public. These developments reflect the infinite possibilities and inevitability of space tourism in near future. However, space tourism may also pose many critical legal issues which must be addressed to ensure the consistent and sustainable development of space tourism, and to secure the rights of all stakeholders involved including operators, passengers, launching State etc. The research paper would highlight the crucial legal issues associated with the space tourism. The paper would critically analyze the efficiency of the present international space treaties in dealing with these issues. At the end, the paper would also attempt to provide few suggestions and solutions to these legal conundrums relating to space tourism. 2021 IAA -
Amorphous Ru-Pi nanoclusters decorated on PEDOT modified carbon fibre paper as a highly efficient electrocatalyst for oxygen evolution reaction
Amorphous Ru-Pi nanoclusters deposited on PEDOT modified carbon fibre paper electrode have been investigated as a potential oxygen evolution electrocatalyst. CFP/PEDOT/Ru-Pi electrode was prepared by electrodeposition of Ru-Pi nanoclusters on PEDOT decorated CFP using cyclic voltammetry (CV). Field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy (FESEM-EDS), attenuated total reflection with Fourier-transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD) were used for physicochemical characterization. Linear sweep voltammetric (LSV) studies corroborated that CFP/PEDOT/Ru-Pi has exhibited higher oxidation peak current when compared to other modified electrodes. CFP/PEDOT/Ru-Pi electrode has displayed better catalytic activity towards oxygen evolution reaction at low onset and over potential. The modified electrode has also offered better stability towards the oxidation reaction in phosphate buffer solution (PBS) and the working stability of these electrodes were determined using LSV and CV. 2021 Elsevier B.V. -
Magnetic coupling across the antiferromagnetic-antiferromagnetic interface
We investigate the magnetic coupling across the antiferromagnetic-antiferromagnetic (AFM-AFM) interface for the prototypical CoO-NiO bilayer system where the bulk Nl temperature (T N ) of NiO is higher than that of CoO. Using the temperature-dependent exchange-scattered electron intensities from the surface AFM lattice, the surface T N of CoO was estimated as a function of the CoO/NiO film thicknesses. Our results show that the surface T N of CoO layers is enhanced significantly from its bulk T N value and approaching the T N of the NiO layers, as the thickness of the CoO layers is reduced to the monolayer limit. Thus, thinner CoO layers are found to have higher T N than thicker layers on NiO, contrasting with the expected finite-size behavior. In addition to the short-range magnetic exchange coupling at the CoO-NiO interface, we observe the existence of a longer-range magnetic coupling across the interface, mediated by the magnetic correlations. Thus, the magnetic proximity effect is attributed to a combination of a short-range and a weaker long-range magnetic coupling, explaining the long AFM order propagation length in AFM-AFM superlattices and bilayers. Further, our results indicate a new approach to tune the AFM Nl temperature by varying the individual layer thickness of the bilayer system through the magnetic proximity effect. 2021 IOP Publishing Ltd. -
Valorization of agro-industrial fruit peel waste to fluorescent nanocarbon sensor: Ultrasensitive detection of potentially hazardous tropane alkaloid
Millions of tonnes of agro-industrial waste are generated each year globally, with the vast majority of it going untreated, underutilized, and disposed of by burning or landfilling, causing severe environmental distress and economic downturn. A practical solution to this global issue is to use green chemistry to convert this waste into value-added products. Accordingly, in the present study, agro-industrial orange peel waste was valorized into fluorescent nanodiamond-like carbon sensor via a green route involving hydrothermal treatment of microwave carbonized orange peel waste. The developed sensor, used for the fluorescence detection of potentially hazardous drug atropine sulfate, exhibits unique dual linearity over concentration ranges of 300 nM to 1 M and from 1 M to 10 M, as well as ultra-low sensitivity of 34.42 nM and 356.46 nM, respectively. Additionally, the sensor demonstrates excellent reproducibility, high stability, and satisfactory recovery when used to identify and quantify atropine sulfate in biological samples and commercially available pharmaceuticals, indicating promising multidisciplinary applications. [Figure not available: see fulltext.] 2021, Higher Education Press. -
Response surface optimization of heat transfer rate in Falkner-Skan flow of ZnO ? EG nanoliquid over a moving wedge: Sensitivity analysis
In this work, the optimization of the heat transfer rate in the Falkner-Skan flow of ethylene glycol-based ZnO nanoliquid passing through a moving wedge is performed using the Response Surface Methodology (RSM). The experimentally estimated nanoliquid properties are included in the calculations for realistic modeling. The heat transfer rate is optimized through the use of the numerical experiment based on the face-centered central composite design (CCF). The sensitivity of the heat transfer rate is evaluated using the obtained quadratic model. The impact of the relevant parameters is displayed graphically using the finite difference method-based solution procedure and analyzed in detail. The interactive impacts of the key parameters are also evaluated using three-dimensional surface plots. The maximum sensitivity of the heat transfer rate is towards the moving wedge parameter. The optimized rate of heat transfer occurs at the high levels of the radiation aspect, moving wedge parameter, and nanoparticle volume fraction. The interactive impacts of the nanoparticles volume fraction and the Falkner-Skan index were found to be non-linear. The movement of the wedge was found to have a significant impact on both the flow field and the rate of heat transfer. 2021 Elsevier Ltd -
BoxBehnken design and experimental study of ciprofloxacin degradation over Ag2O/CeO2/g-C3N4 nanocomposites
Abstract: The presence of pharmaceutical residues notably antibiotics in the environment is an increasing concern due to their persistence and toxicity. Developing efficient and eco-friendly methods to eliminate antibiotic residues from water bodies has become a major environmental challenge. CeO2 doped with a heteroatom forms a hybrid structure with g-C3N4 and could serve as an efficient photocatalytic agent. In this study, CeO2/g-C3N4 and Ag2O/CeO2/g-C3N4 hybrid catalysts were prepared for UV light degradation of ciprofloxacin (CIP) antibiotic. The various factors that influence the degradation were experimentally optimized. The kinetics of the degradation was investigated using the LangmuirHinshelwood kinetic model. The effect of three operational parameters influencing the photocatalytic degradation has been evaluated using BoxBehnken design of response surface methodology. The highest degradation of CIP was observed at CIP concentration of 10?g/L with a catalyst amount of 30mg after 2.5h. Efficient charge separation was achieved from the dopant and the existing integrated electric field of the heterojunction showed impressive higher activity. Graphic abstract: [Figure not available: see fulltext.]. 2020, Islamic Azad University (IAU). -
ZnO:Al thin films from (Al2O3)x(ZnO)(1-x) powder targets by magnetron sputtering
In the present work we prepared Aluminum doped Zinc Oxide (AZO) thin films from powder targets. Various concentrations (W/W percentages) of Al2O3 such as1%, 2%, 3%, 4%, 5%, 6%, 7% and 8% were mixed in ZnO powder and made in the form of a 3 inch disc target. These ceramic targets are sputtered in RF magnetron sputtering unit for the deposition of AZO thin films. Optical and electrical properties are analyzed to get an optimized percentage of mixing for achieving high transparency and low resistivity. At Al2O3 percentage of 3% there is a considerable decrement in the resistivity, and at 7% there is a considerable decrease in the optical transmittance. Mobility and carrier concentration are increasing with Al2O3 percentage. Bandgap of the films is observed to be decreasing with increasing the Al2O3 percentage. 2021 Elsevier Ltd and Techna Group S.r.l. -
Fractional approach for analysis of the model describing wind-influenced projectile motion
In this paper, we find the solution for coupled equations describing the projectile motion with wind-influence using q-homotopy analysis transform method (q-HATM). The projectedmethod is elegant amalgamations of q-homotopy analysis scheme and Laplace transform, and fractional derivativedefined withCaputo-Fabrizio (CF) operator. Moreover, the physical natures of the obtained results have been captured in terms of plots for diverse mass, external force and fractional order. The achievedconsequences elucidate that, the hiredsolution procedure is easy to implement, highly methodical as well as accurate to analyse the behaviour of system of nonlinear differential equations of both integer and fractional order describing connected areas of science and engineering. 2021 IOP Publishing Ltd. -
Identity-based message authentication scheme using proxy vehicles for vehicular ad hoc networks
Message authentication verifies the identity of the sender vehicle, ensuring it in between vehicles and Road Side Units (RSU) is an essential part of Vehicular Adhoc Networks. Signature verification in RSUs will be troublesome if a large number of vehicles enters in its region at the same time. In such cases the efficiency of the RSUs will be affected due to high computational overhead. To address this issue, proxy vehicle based message authentication scheme (ID-MAP) is proposed by Asaar et al. (ITVT 67: 5409, 2018). It uses proxy vehicles to reduce the overheads of the RSU by verifying multiple messages at the same time. Even though it deals with the efficiency issues of RSU, the computational cost of signature generation is high. Since the ability of a vehicle to act as a proxy vehicle is based on the number of signed messages, it has a major impact. It also cannot guarantee privacy preservation and hence it is insecure against attacks based on privacy preservation. It also has other drawbacks like storage issues and high overheads. Hence, a new identity based message authentication using proxy vehicles is proposed in this paper. Elliptic Curve Cryptography based scheme is used without pairings for message authentication. Proxy vehicles will verify multiple messages from vehicles through batch verification and send the result to the RSU. The identity of multiple proxy vehicles will be verified by RSU, it can also cross check the correctness of the received result. Thereby RSUs can verify a large number of messages at the same time with the help of proxy vehicles. Security analysis shows that if each proxy vehicle verifies 300 messages of its neighbor vehicles, then with the help of proxy vehicles an RSU can verify 226,244 messages per second which is 40% less than that of ID-MAP scheme. It also shows that the computational cost to generate a signature in the proposed scheme is 50% less than that of ID-MAP scheme. 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Biodegradation of polypropylene films by Bacillus paralicheniformis and Lysinibacillus fusiformis isolated from municipality solid waste contaminated soil
The fossil fuel or petroleum derived plastics are applied in our routine life because of their easy availability. Distribution and contamination of the plastics in the landfills are the major reasons for these biodegradation study. This current study reveals the biodegradation of polypropylene films and the growth of Bacillus paralicheniformis and Lysinibacillus fusiformis isolated from plastic contaminated soil collected from municipality solid waste management site. The degradation rate of PP films was confirmed by the results of biodegradation analysis. The growth of Bacillus paralicheniformis and Lysinibacillus fusiformis had shown OD values at 600nm after the degradation period of 4 weeks increasing from 0.131 to 0.334 and 0.148 to 0.213 respectively. The viable cell count increased from 804cells/ml to 1204cells/ml and 10.104cells/ml to 15.204cells/ml respectively. The physical and chemical changes of PP films were confirmed by FT-IR and XRD analysis. These analysis confirmed that the bacterial strains have the ability to change the chemical and physical nature of PP films and can utilize the PP films as sole carbon source. 2021 World Research Association. All rights reserved. -
An analytical model for a TFET with an n-doped channel operating in accumulation and inversion modes
The tunnel field-effect transistor (TFET) is an ambipolar device that conducts current with the channel in both accumulation and inversion modes. Analytical expressions for the channel potential and current in a TFET with an n-doped channel when operating in the accumulation and inversion modes are proposed herein. The potential model is derived by solving the two-dimensional (2D) Poisson equation using the superposition principle while considering the charges present in the channel due to electron or hole accumulation along with the depletion charges. An expression for the tunneling current corresponding to the maximum tunneling probability is also derived. The tunneling current is obtained by analytically calculating the minimum tunneling length in a TFET when operating in the accumulation or inversion mode. The results of the proposed potential model is compared with technology computer-aided design (TCAD) simulations for TFET with various dimensions, revealing good agreement. The potential and current in an n-type TFET (nTFET) obtained using the proposed models are also analyzed. 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
On ? -Vertex Choosability of Graphs
A connected, simple graph G with vertex set V(G) = { 1 , 2 , , n} is said to be vertex (n,k)-choosable, if there exists a collection of subsets { Sk(v) ? V(G) : v? V} of cardinality k, such that Sk(u) ? Sk(v) = ? for all uv? E(G) , where k is a positive integer less than n. The maximum value of such k is called the vertex choice number of G. In this paper, we introduce the notion of ?- choosability of graphs in terms of their vertex (n,k)-choice number and initiate a study on the structural characteristics of ?-choosable graphs. 2020, The National Academy of Sciences, India. -
Application of response surface methodology to optimize lead(Ii) ion adsorption by activated carbon fabricated from de oiled soya
Lead(II) ion a heavy metal is known for its toxicity. An initiative has been taken in this study, to adsorb toxic lead(II) ion using activated carbon made of de oiled soya, by an aqueous solution through batch adsorption methodology. Adsorption process variables such as adsorbent dose, contact time, solution pH, and lead(II) ion concentration were optimized by central composite design (CCD). To find the interaction between process variables, response surface plots were utilized using response surface methodology. Design-Expert software version 7 was resorted to in this experiment. It was observed that the components from the analysis of variance of the CCD revealed that the selective process independent variables had significant control over adsorption capacity. Desirability function was used to appraise the factors and response in adsorption experiments to find an optimum point where the preferred adsorption could be obtained. Adsorption process with the application of activated carbon developed from de-oiled soya meritoriously removed lead(II) ion with an optimum adsorption capacity of 26.279 mg/g for an initial concentration of lead(II) at 60 mg/L. 2021 Desalination Publications. All rights reserved. -
A new extension of hesitant fuzzy set: An application to an offshore wind turbine technology selection process
Wind energy is an energy source that is naturally clean, safe and cheap. It comes from a variety of sources. The electric energy generated by a wind turbine manifests as kinetic energy throughout the earth. The energy received from the wind is clean and is permanently available and can be generated forever. Turbine characteristics also have an impact on wind energy production. The turbine properties within a wind farm are important in estimating the load on power generation and wind turbine energy. The amount of energy released is calculated according to the type of the turbine model applied. In many situations, the choices of turbine model can incur various vague and complicated hesitation situations. To manage this situation, a hesitant fuzzy set with the Multi Criteria Decision Making (MCDM) is used. In the present research, the newly proposed Normal Wiggly Hesitant Fuzzy-Criteria Importance Through Intercriteria Correlation (NWHF-CRITIC) and Normal Wiggly Hesitant Fuzzy-Multi Attribute Utility Theory (NWHF-MAUT) methods were employed to rank turbine models based on quality, power level, voltage, and capacity. As part of this process, the NWHF method was utilized to extract and gather deeper information from the decision-makers. 2021 The Authors. IET Renewable Power Generation published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology. -
Line completion number of grid graph Pn Pm
The concept of super line graph was introduced in the year 1995 by Bagga, Beineke and Varma. Given a graph with at least r edges, the super line graph of index r, Lr(G), has as its vertices the sets of r-edges of G, with two adjacent if there is an edge in one set adjacent to an edge in the other set. The line completion number lc(G) of a graph G is the least positive integer r for which Lr(G) is a complete graph. In this paper, we find the line completion number of grid graph Pn Pm for various cases of n and m. 2021 Azarbaijan Shahid Madani University. -
Corporate governance practices and shareholder protection in India
The present study aims to study the corporate governance practices and shareholder protection among Indian companies. For this purpose a sample of 100 companies are selected. The selected companies listed in BSE 100 Index. The required data are collected from various secondary sources like company website, annual report, notices and annual general meeting. Data were collected using a structured schedule adapted from G20/OECD principles of corporate governance. The finding of the study indicates that out of the selected companies, the level of practicing the corporate governance are not the same. The result of this study will help investors in identifying the companies for their investment, based on their priorities by keeping corporate governance scorecard as a benchmark. It will also be helpful for companies to see their scorecard and check the parameters for improvement and to attract and safeguard the investors and other stakeholders. This study will also add value to the existing literature in their relevant field. Indian Institute of Finance.