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Generalized Ricci soliton and paracontact geometry
In the present paper, we study generalized Ricci soliton in the framework of paracontact metric manifolds. First, we prove that if the metric of a paracontact metric manifold M with Q?= ?Q is a generalized Ricci soliton (g,X) and if X? 0 is pointwise collinear to ?, then M is K-paracontact and ?-Einstein. Next, we consider closed generalized Ricci soliton on K-paracontact manifold and prove that it is Einstein provided ?(?+ 2 n?) ? 1. Next, we study K-paracontact metric as gradient generalized almost Ricci soliton and in this case we prove that (i) the scalar curvature r is constant and is equal to - 2 n(2 n+ 1) ; (ii) the squared norm of Ricci operator is constant and is equal to 4 n2(2 n+ 1) , provided ??? - 1. 2021, Instituto de Matemica e Estattica da Universidade de S Paulo. -
A study on heat transfer in three-dimensional nonlinear convective boundary layer flow of nanomaterial considering the aggregation of nanoparticles
Thermal systems of solar collectors, electronic cooling, nuclear reactors, and combustion operate at high thermal conditions, and in such circumstances, the density relation of the working fluids with the thermal field may not be linear. The working fluid features are significantly affected by nonlinear density temperature fluctuations. Therefore, a theoretical study of the quadratic Boussinesq approximation (with quadratic density temperature [QDT] variation) and quadratic Rosseland radiation on the three-dimensional boundary layer dynamics and heat transport of ethylene glycol-based titania nanomaterial is carried out. The phenomenon of the kinematics of nanoparticle aggregation is also analyzed by considering modified models proposed by MaxwellBruggeman and KriegerDougherty for thermal conductivity and dynamic viscosity. The flow is induced by the elongation of a flexible flat plate in two directions. A comparison of heat transfer features of linear elongation of the plate and nonlinear elongation of the plate is conducted. The Rosseland radiative heat flux is studied in three different forms. The governing nonlinear equations are treated using apt nondimensionalization, stretching transformation, and then by using the Richardson extrapolation method. The results are presented via plots to analyze the impact of key parameters involved in the model. The magnitude of the nanomaterial temperature is enhanced due to the kinematics of nanoparticle aggregation. Among linear, quadratic, and nonlinear forms of Rosseland radiative heat flux, the quadratic radiative heat is more suitable when QDT is considered. A positive relationship is found between heat transfer and volume fraction and a positive relationship is observed between heat transfer and the QDT factor. The magnitude of the velocities and thermal field is higher for flow driven due to the linear elongation of the plate than the nonlinear case. 2021 Wiley Periodicals LLC -
Analysis of multilayer convective flow of a hybrid nanofluid in porous medium sandwiched between the layers of nanofluid
AgBr acts as a good sensitizer for titanium oxide, hence TiO2AgBr nanoparticles exhibit high photocatalytic activity which helps decompose methyl orange under visible light irradiation. Methyl orange is a chemical compound that is hard to degrade and has high stability. It is photoreactive and can capture photons from the sun and is highly used as a light harvester in solar cells, hence, it is used in solar applications. In view of this, the present article deals with the analysis of heat transfer in a multilayer flow of two immiscible nanofluids in a vertical channel that finds application in the fields of solar reactors, electronic cooling, and so on. The mathematical model involving the effect of thermal radiation and the presence of heat source is in the form of a system of ordinary differential equations. This system of equations is simplified using the differential transform method-Padapproximant and the resulting equations are solved algebraically. It is observed that the temperature of the coolant does not reach its saturation point faster due to the presence of different base fluids that differ in their thermal conductivity. This helps in maintaining theoptimum temperature of the system. 2021 Wiley Periodicals LLC -
An Adoptable Multi-Criteria Decision-Making Analysis to Select a Best Hair Mask Product-Extended Weighted Aggregated Sum Product Assessment Method
Hair masks (HMs) act as one of the solutions for most of the hair problems like dandruff, frizziness, breakage, premature- greying and so on. Due to its various benefits, HM products are acquiring more popularity among the individuals. As there are different varieties of HM products available in the market, the confusion arises in choosing a HM which suits the individuals hair profile and causes less side effects. Here, we have employed multi-criteria decision-making (MCDM) combined with fuzzy set theory to obtain better results. We used the extended Weighted Aggregated Sum Product Assessment (WASPAS) method based on trapezoidal interval type-2 fuzzy set (TIT2FS) in this research paper to handle vagueness and complexity in real-world problems. For determining the objective weights of the criteria, we used the entropy method of weight finding. An example of selecting a hair mask product (HMP) among four alternatives based on five criteria is provided to illustrate the applicability of the proposed method. In comparison to other MCDM methods, the approach yielded more practical results. By doing a sensitive study, the methods stability is also assessed. 2021, The Author(s). -
Student alienation and perceived organizational culture: A correlational study
It is generally expected that the students are supposed to gain an engaging and enriching experience throughout their journey of higher education. The educational institutions have to take up the responsibility to ensure that students are engaged meaningfully and are in a state of well-being. However, in the present scenario, students at colleges and universities have started to feel alienated from the campus life. Research shows that alienation levels are rising among the youth. Factors like stress, coping mechanism, restrictive parental behavior, peer pressure, academic performance, and organizational culture have an impact on alienation among the students. This study attempts to understand the relationship between student alienation and organizational culture in an educational institution. The study employed a descriptive correlational design and collected data from 600 under graduate students studying in a university. The study used student alienation scale and organizational culture assessment instrument to collect the survey data. Study revealed that there is a negative correlation between student alienation and organizational culture. There were 30% variation in student alienation is explained by different types of organizational culture. Clan culture reduces student alienation compared to hierarchy culture. The researchers urge for further research to identify ideal organizational cultures that can promote student engagement and student well-being. 2021, Institute of Advanced Engineering and Science. All rights reserved. -
Irreversibility analysis of radiative heat transport of Williamson material over a lubricated surface with viscous heating and internal heat source
Thecurrent research explores the importance of surface lubrication and convective boundary conditions in the flow of non-Newtonian Williamson material. Rosseland radiative heat flux and viscous heating are also considered. The phenomenon of the generation or absorption of internal heat is studied. The conservation laws of momentum, mass, and energy are used to model the problem with suitable boundary conditions. With the help of appropriate transformations and the finite difference method, highly nonlinear equations of governance are solved. The influence of key parameters on Bejan number, velocity, entropy production, temperature profiles are analyzed by parametric analysis. It was found that the entropy generation rate improves due to the presence of the Rosseland radiative heat flux and the convective boundary on the lubricated surface. The sliding condition on the lubricated surface has lengthened the structure of the velocity boundary layer, while this trend is opposite to the thermal field. The dissipation due to the viscous forces of the Williamson material improves the production of entropy. 2021 Wiley Periodicals LLC -
Environmental Management: Pragmatic Suitability of Low Cost Activated Carbon in Lead (II)Ion Removal by Continuous Mode of Adsorption
Heavy metals such as chromium, lead, and arsenic are usually present in trace amounts in natural waters but many of them are toxic even at very low concentrations. An increasing quantity of heavy metals in our resources is currently an area of greater concern, especially since a large number of industries are discharging their metal containing effluents into freshwater without any adequate treatment. Activated carbons show a significant ability in removing heavy metal ions from an aqueous solution by adsorption, which has been examined by many researchers. Activated carbon derived from Manilkarazapota tree-wood (MZTWAC), which was found to be a suitable adsorbent for the removal of lead ions through continuous adsorption mode, was examined in this paper. A breakthrough curve has been plotted to find the effect of initial concentration and adsorbent bed height in the adsorption of lead (II)ion through MZTWAC. The breakthrough time and the saturation time increased as the initial concentration increased from 40 mg.L-1 to 60 mg.L-1. The saturation time was in the incremental mode when the bed height was increased from 5 cm to 7 cm bed thickness for 40 mg.L-1 concentration. Adams-Boharts model perfectly fits with this fixed-bed column in the removal of lead(II) from an aqueous solution using MZTWAC. Activated carbon derived from MZTWAC is better suited for the purpose of detoxifying metal-contaminated wastewater. 2021 Technoscience Publications. All rights reserved. -
Volatility in Indian stock markets during COVID-19: An analysis of equity investment strategies
The aim of the paper is to evaluate the impact of novel COVID-19 on the returns and volatility of Indian stock markets with special reference to equity investment strategies of the Bombay Stock Exchange. For the purpose of evaluating the impact, the study has applied GARCH. The research has considered a time frame from March 2015 to January 2021. Prior to implementing GARCH model, pre-estimation tests (i.e., augmented Dickey-Fuller and ARCH-Lagrange multiplier) were conducted. Outcomes clearly indicate that the returns during the crisis for all the strategy indices have been negative, which means that the COVID-19 outbreak resulted in massive losses. Additionally, 'during crisis' period showed an increase in volatility for all the strategy indices depicting that the pandemic has a long-lasting effect and will take time to fade off. This research will help the investors in the investment decision process by giving them insights about the different strategies. 2021. -
Network pharmacological evaluation for identifying novel drug-like molecules from ginger (Zingiber officinale Rosc.) against multiple disease targets, a computational biotechnology approach
Ginger (Zingiber officinale Rosc.) is a popular spice used globally in ethnic cuisines and witnessed its extensive use in traditional medicine. In this study, we identified 12 phytochemicals from the ginger rhizome extract (hexane) through GC/MS analysis. After evaluating drug-likeliness, these phytochemicals were docked with 16 target proteins in silico, and docking scores were compared with their respective control drugs. Furthermore, multivariate statistical analysis (principal component analysis-PCA) was performed, and three different chemical clusters were identified. Pharmacophore analysis further identified common functional descriptors in the compounds under study. Finally, we developed a unique three-level network taking phytochemicals, target proteins and associated diseases based on the optimum docking scores. Overall, Oleic acid, Palmitic acid and Shogaol showed the highest coverage to the target proteins (12, 10 and 9 targets, respectively) and Oleic Acid scored the highest (5956) in PatchDock when docked against Peroxisome proliferator-activated receptor gamma (PDB id 1KNU, UniProt id P37231). This work provided significant insight into developing the protocol for rapid identification of potential drug likeliness of the identified phytochemicals. Graphic abstract: [Figure not available: see fulltext.]. 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature. -
A Simple and Efficient [(n-Bu3Sn)2MO4]n Catalyzed Synthesis of Quinazolinones and Dihydroquinazolinones
A novel unprecedented approach for the synthesis of various quinazolinones and dihydroquinazolinones has been using [(n-Bu3Sn)2MO4]n as a catalyst. The reaction has been screened in various solvents and a gram scale experiment has also been demonstrated under given conditions. Further, the substrate scope of the reaction and the recyclability of the catalyst have also been studied. 2021 Taylor & Francis Group, LLC. -
Natural polymer-based hydrogels as prospective tissue equivalent materials for radiation therapy and dosimetry
Natural polymer-based hydrogels have been extensively employed in tissue engineering and biomedical applications, owing to their biodegradability and biocompatibility. In the present work, we have investigated the efficacy of hydrogels such as agarose, hyaluronan, gelatin, carrageenan, chitosan, sodium alginate and collagen as tissue equivalent materials with respect to photon and charged particle (electron, proton and alpha particle) interactions, for use in radiation therapy and dosimetry. Tissue equivalence has been investigated by computing photon mass energy absorption coefficient (?en/?), kinetic energy released per unit mass (KERMA), equivalent atomic number (Zeq) and energy absorption build-up factors (EABF) relative to human tissues (soft tissue, cortical bone, skeletal muscle, breast tissue, lung tissue, adipose tissue, skin tissue, brain) in the energy range of 0.01515MeV. Ratio of effective atomic numbers (Zeff) have been examined for tissue-equivalence in the energy range of 10keV1GeV for charged particle interactions. Analysis using standard theoretical formulations revealed that all the selected natural polymers can serve as good tissue equivalent materials with respect to all human tissues except cortical bone. Notably, sodium alginate, collagen and hyaluronan are found to have radiation interaction characteristics close to that of human tissues. These results would be useful in deciding on the suitability of a natural polymer hydrogel as tissue substitute in the desired energy range. 2021, Australasian College of Physical Scientists and Engineers in Medicine. -
Improvising data security measures using rajan transform
Data security has always been a concern with the use of a large amount of data in our day-to-day life. There are many methods suggested and presented to secure data during the stages of its preprocessing and post-processing. However, many of them are not following the process of Homomorphism. During the study of Fast Fourier transform (FFT), Hadamard transform (HT) and Rajan transform (RT), this research work encountered a method that uses the cyclic, dyadic and graphical inverse properties of data and encrypts them which makes them homomorphic. This paper is targeting to improvise the data security measures using Homomorphism-based Rajan Transform, a method, which can help in securing data while data processing. The proposed methodology works in such a way that the encrypted data is available for processing without decrypting data into the original form. The performance of the proposed method is described by the efficiency of the algorithm, key size, Block size, and no of rounds required to complete the encryption. It has been found, if we take 512 bits of input data to get 512-bit ciphertext, it takes 9 rounds and generates a 4608-bit key. 2021 Taylor's University. All rights reserved. -
Impact of Technology Readiness and Techno Stress on Teacher Engagement in Higher Secondary Schools
Rapid technology advancements resulted a fundamental shift in the education sector which redefined the teaching-learning process and teacher engagement. Based on numerous studies on work engagement models and technology readiness, this study explores, how the teachers' readiness to embrace educational technologies, impact on teacher engagement. With stratified cluster sampling model, data were collected from principals, managers, students and 122 teaching staff from the Higher Secondary Schools of Kerala participated in this quantitative study using standardized tools. The study affirmed that age has negative relation with technology readiness and teacher engagement shows an organic technology adoption trend than a disruptive style. Teachers were highly engaged with students-colleagues and varied across experience/age groups. Technology readiness factors positively impacted on social engagements with students-colleagues. As education technology usage is exponential, more future research is needed. 2021 Research Group Education and Virtual Learning (GREAV). All rights reserved. -
Phytochemical analysis, anti-oxidant properties and pass assisted prediction of biological activity of sargassum wightti j. Agardh, sargassum ilicifolium (turner) C. Agardh and sargassum lanceolatum J. Agardh
The present study was carried out to determine the phytoconstituents and anti-oxidant properties present in the Sargassum wightti, Sargassum ilicifolium and Sargassum lanceolatum using GC-MS analysis and predict the biological activity by PASS prediction. Gas chromatography/mass spectrometry (GC/MS) analysis was performed on Shimadzu GC interfaced with mass spectrometry using SH-RxiTM-5Sil (Shimadzu) column. The spectra of the phytoconstituents were obtained by the PASS version (http:// www.way2drug.com/passonline). The prediction was based on an analysis of the structure-activity relationships (SAR) in the training set containing information on the structure. GC-MS analysis revealed 39 compounds in S. wightti, 60 compounds in S. lanceolatum and 15 compounds in S. ilicifolium. Common compounds found in these three Sargassum species were 1s,4R,7R,11R-1,3,4,7-Tetramethyltricyclo [5.3.1.0(4,11)] undec-2-en-8-one,2,4-Di-tert-butyl phenol, 1-Decanol, 2-hexyl, Hexatriacontyl-trifluoroacetate, Nonyltetradecyl ether, Neophytadiene, Hexadecane. Sargassum species are rich in anti-oxidant, anti-inflammatory, anti-bacterial and anti-viral properties. The present study proved the presence of bioactive compounds and phytochemical compounds in three species of Sargassum available in Indian coastal regions. 2021, Agri Bio Research Publishers. All rights reserved. -
Changing look AGN Mrk 590: Broad-line region and black hole mass from photometric reverberation mapping
We present the results of photometric reverberation mapping observations on the changing look active galactic nucleus Mrk 590 at z = 0.026. The observations were carried out from 2018 July to December using broad-bandB-,R-, and narrow-band H ? and S ii filters. The B band traces the continuum emission from the accretion disc, the R band encompasses both the continuum emission from the accretion disc and the redshifted H ? line from the broad-line region (BLR), the S ii band contains the redshifted H ? emission and the H ? band traces the continuum emission underneath the S ii band. All the light curves showed strong variation with a fractional root-mean-square variation of 0.132 0.001 in the B band and 0.321 0.001 in H ? line. From cross-correlation function analysis, we obtained a delayed response of H ? line emission to the opticalB-band continuum emission of $21.44^{+1.49}_{-2.11}$ d in the rest frame of the source, corresponding to a linear size of the BLR of 0.018 pc. This is consistent with previous estimates using H ?. By combining the BLR size with the H ? line full width at half-maximum of 6478 240 km s-1 measured from a single-epoch spectrum obtained with the Subaru telescope, we derived a black hole mass of $1.96^{+0.15}_{-0.21}\times 10^8 {\rm M}_{\odot }$. 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. -
A study of diesel and Pongamia Pinnata biodiesel combustion in compression ignition engines using zero-dimensional modelling and experimental methods
The present study develops a single-zone zero-dimensional progressive combustion simulation model using Python programming language for compression ignition engines. The model is capable of predicting in-cylinder pressure, heat release rate, engine performance, and emissions characteristics. The numerical model is experimentally validated using resuts from engine testing for diesel, Pongamia Pinnata biodiesel and diesel-biodiesel blends. The chemical composition of fuel is identified using Gas Chromatography-Mass Spectrometry. The values of power output, mean effective pressure and exhaust oxygen concentration are independently obtained from the numerical model and from the experiments. The engine performance is not significantly affected for biodiesel to diesel blending ratio of up to 30%. A higher oxygen concentration in the exhaust gas is observed with increase in blending ratio. The developed numerical model would be useful in studying the performance and emission characteristics for any alternative fuel with known calorific value and chemical composition. 2020 Informa UK Limited, trading as Taylor & Francis Group. -
Entomotoxic proteins of Beauveria bassiana Bals. (Vuil.) and their virulence against two cotton insect pests
Entomopathogenic fungi are widely used as biocontrol agents against several agricultural pests. Among them, Beauveria bassiana is considered the important one against insect and other arthropod pests. The entomotoxic proteins of B. bassiana were extracted by Sephadex G-25 column, and fractionated using HPLC (BBI, BBII and BBIII) and tested against two hemipteran insect pests i.e., Dysdercus cingulatus Fab. and Phenacoccus solenopsis Tinsely (Hemiptera: Pseudococcidae). Results indicated that protein content was higher in fraction BBII than BBI and BBIII. The vibration frequency in FT-IR obtained with a range of 1650 to 1580 cm?1. Bioassays of fractions (I, II and III) reveal that BBII was highly virulent against third nymphal instar of D. cingulatus (LC50 = 800.2 ppm) and adults of P. solenopsis adult (LC50 = 713.3 ppm). Considering the high virulence of BBII subjected to SDS-PAGE, HPLC and MALDI-TOF analyses. Analyses reveals the presence of 174 kDa and designated as BBF2. These results concluded that the entomotoxic protein of B. bassiana can be utilized for management of these investigated hemipreran pests. Further investigations are necessary for the field application of this entomotoxin against these pests or other insect pests. These results also could be helpful for establishing novel biotechnological uses for this fungus. 2021 The Authors -
INCLUSIVE LAW SCHOOL CLINICS: Institutionalizing Effective and Accountable Justice for All
Poor people are often denied access to the courts due to expensive legal fees. Preventing free access to justice violates a fundamental constitutional principle and universal international norms. The recognition of access to justice and the rule of law as outcomes and facilitators of sustainable development is a unique feature of the 2030 Agenda. This study shows that providing affordable and timely access to justice institutions and legal aid services will help achieve the Sustainable Development Goals (SDG) 16 targets of peace, justice, and strong institutions. Indian law school clinics have a unique opportunity to achieve the goal through institutionalized clinical legal education. The Advocates Act of 1961 requires an amendment to allow law students and faculty to represent pro bono clients. The study infers that completely institutionalizing the law school legal aid clinics as part of clinical legal education is a powerful platform to promote equal access to justice to all. 2021, Dharma Research Association. All rights reserved. -
A new computational technique for the analytic treatment of time-fractional EmdenFowler equations
This paper presents the study of fractional EmdenFowler (FEF) equations by utilizinga new adequate procedure, specifically the q-homotopy analysis transform method (q-HATM). The EF equation has got greater significance in both physical and mathematical investigation of capillary and nonlinear dispersive gravity waves. The projected technique is tested by considering four illustrations of the time-fractional EF equations. The q-HATM furnish ?, known as an auxiliary parameter, by the support of ? we can modulate the various stages of convergence of the series solution. Additionally, to certify the resolution and accurateness of the proposed method we fitted the suitable numerical simulations. The redeem results guarantee that the proposed process is more convincing and scrutinizes the extremely nonlinear issues emerging in the field of science and engineering. 2021 International Association for Mathematics and Computers in Simulation (IMACS) -
Do Frequency of Visit and Length of Stay Alter Perceived Cognitive Destination Image? A Multivariate Approach
The Indian tourism industry is competing with global destinations through effective and lucrative strategies. Strategic destination branding is one of the finest ways of achieving the frontier. This requires careful analysis of tourists' perception and behavior from time to time and inculcate insights on the branding process. Accordingly, this research work is an extract from a major research that focused on whether the behavioral elements such as tourists' frequency of visit and length of stay to/in the destination influenced the perceived cognitive destination image. Even though literary sources indicated the connection between these factors, a void was identified in terms of the aspects of the cognitive image, specifically in the Indian context. Hence, a district in Tamil Nadu that had high tourist attractions and potentialities to serve distinct tourist motives was chosen for the study. The respondents answered a structured questionnaire that contained the necessary questions and statements on tourists' sociodemographic characteristics, frequency of visit, length of stay, and perception of the cognitive image of the destination. The sample size was rounded to 327 after data cleaning. Simple percentage analysis revealed that the highest percentage of tourists were frequent visitors and stayed in the destination for more than a week. This is a good sign for marketers to increase the tourists' inflow and invest in branding strategies. The multivariate analysis of variance technique of SPSS was employed to analyze the data. The results indicated that despite the frequency of visit and length of stay, some of the cognitive belief aspects remained unaltered. Suggestions were made to the marketers on deploying the cognitive image aspects while designing the advertisement campaigns and including the cognitive image elements in the branding process. Theoretical implications were also indicated on the outcome of this research. Also, limitations were stated in terms of the sample size, research location, and other aspects. Scope for further research was also indicated. 2021, Associated Management Consultants Pvt. Ltd. All rights reserved.