Browse Items (11810 total)
Sort by:
-
[18-C-6H3O+]: an in-situ generated macrocyclic complex and an efficient, novel catalyst for synthesis of pyrano[2,3-c]pyrazole derivatives
Synthesis of small aromatic heterocycles is of greater importance in the organic chemistry due to their vibrant applications in pharmaceuticals, agrochemicals and veterinary products. Pyranopyrazoles are one such class of heterocycles associated with numerous applications. Hence herein we report a multicomponent crown ether catalyzed, ultrasound irradiated methodology to make different functionalized pyranopyrazoles in a single step. This technique involves the in-situ generation of [18-C-6H3O+][OH?] complex, which in turn activates the aromatic aldehyde and aids in the facile nucleophilic addition. 2020, The Author(s). -
Modeling and computational fluid dynamic analysis on a non-AC bus coach system
The main objective of this paper is to reduce the drag force and enhance the uniform airflow inside an existing non-air-conditioning bus coach system. The redesigning of an existing bus carried out by considering the forces that reduce the moment of the bus. Modeling and meshing was carried out using solid works and Hypermesh software, respectively. Finally, the problem is simulated using Ansys fluent software and analysis is carried out for different bus models. The noteworthy findings state that the air resistance of the vehicle is found to be 812.74 N and coefficient of drag is 0.67 are less as compared to existing bus model. 2020 Wiley Periodicals LLC -
Quasar catalogue for the astrometric calibration of the forthcoming ILMT survey
Quasars are ideal targets to use for astrometric calibration of large scale astronomical surveys as they have negligible proper motion and parallax.The forthcoming 4-m International Liquid Mirror Telescope (ILMT) will survey the sky that covers a width of about 27?. To carry out astrometric calibration of the ILMT observations, we aimed to compile a list of quasars with accurate equatorial coordinates and falling in the ILMT stripe. Towards this, we cross-correlated all the quasars that are known till the present date with the sources in the Gaia-DR2 catalogue, as the Gaia-DR2 sources have position uncertainties as small as a few milli arcsec (mas). We present here the results of this cross-correlation which is a catalogue of 6738 quasars that is suitable for astrometric calibration of the ILMT fields. In this work, we present this quasar catalogue. This catalogue of quasars can also be used to study quasar variability over diverse time scales when the ILMT starts its observations. While preparing this catalogue, we also confirmed that quasars in the ILMT stripe have proper motion and parallax lesser than 20 masyr- 1 and 10 mas, respectively. 2020, Indian Academy of Sciences. -
Restrained geodetic domination in graphs
Let G = (V,E) be a graph with edge set E and vertex set V. For a connected graph G, a vertex set S of G is said to be a geodetic set if every vertex in G lies in a shortest path between any pair of vertices in S. If the geodetic set S is dominating, then S is geodetic dominating set. A vertex set S of G is said to be a restrained geodetic dominating set if S is geodetic, dominating and the subgraph induced by V - S has no isolated vertex. The minimum cardinality of such set is called restrained geodetic domination (rgd) number. In this paper, rgd number of certain classes of graphs and 2-self-centered graphs was discussed. The restrained geodetic domination is discussed in graph operations such as Cartesian product and join of graphs. Restrained geodetic domination in corona product between a general connected graph and some classes of graphs is also discussed in this paper. 2020 World Scientific Publishing Company. -
Study of rotating Bard-Brinkman convection of Newtonian liquids and nanoliquids in enclosures
Taylor-Bard convection of water and water-based nanoliquids confined in three different types of high porosity rectangular enclosures, viz., shallow, square and tall, is studied analytically using both infinitesimal and finite amplitude stability analyses. We make use of the modified-Buongiorno-Brinkman model(MBBM) for the governing equations concerning nanoliquid-saturated porous enclosures bounded by rigid-rigid boundaries and obtain analytical results. Among three types of enclosures, maximum and minimum heat transfers are observed in tall and shallow enclosures respectively. Water well dispersed with a dilute concentration of single-walled carbon nanotubes(SWCNTs) is considered as a working medium. The water-SWCNTs is able to flow in the porous medium because the medium is loosely-packed with porosity in the range 0.5 ? ? ? 1. In addition to this, the maximum volume fraction of nanoparticles considered in the system is 6% and thus this does not alter the fluidity of the system. We found from the study that the presence of low concentration(volume fraction-0.06) of SWCNTs in a water-saturated porous medium effectively improves the heat transport of the system due to its high thermal conductivity and large surface area. Due to the presence of a porous medium, however, the onset of convection gets delayed and heat transport in nanoliquids gets substantially reduced in a Bard-Brinkman configuration resulting from the weak thermal conductivity of the porous medium. Thus the porous medium acts as the heat storage system. Also, in a rotating frame of reference the heat transport gets reduced and rotation serves as an external mechanism of regulating heat transport in the system. The nonlinear dynamics of the system is studied using the 6-mode Lorenz model. Chaotic motion in the system is studied using the maximum Lyapunov exponent(MLE). The Hofp-bifurcation point of the system along with the MLE is used to investigate periodic, nearly periodic and mildly chaotic behaviors of the system. 2020 -
Psychological distress among doctoral scholars: Its association with perseverance and passion
Background: the study examined psychological distress and its association with perseverance and passion for long term goals among 400 Ph.D. scholars from Pondicherry University. MethODs: the sample collected through multi-stage convenience sampling technique was assessed using a structured Questionnaire, Depression, anxiety and stress scale (Dass-21), Grit scale and Flourishing scale. resULts: the results showed that 7.5% and 4.5% had severe and extremely severe depression, 12.5% and 20% had severe and extremely severe anxiety, and 5% and 1.5% had severe and extremely severe stress. the data was collected from one indian University and analyzed based the information gathered through self-report inventory. cONcLUsiONs: congenial family environment, good relationship with parents and friends were observed to be positive factors for psychological well-being. there is an urgent need to extend mental health support services to the PhD scholars especially for those who were suffering from severe and extremely severe psychological distress. 2020 Edizioni Minerva Medica Online version at http://www.minervamedica.it -
More insights into bar quenching: Multi-wavelength analysis of four barred galaxies
The underlying nature of the process of star formation quenching in the central regions of barred disc galaxies that is due to the action of stellar bar is not fully understood. We present a multi-wavelength study of four barred galaxies using the archival data from optical, ultraviolet, infrared, CO, and HI imaging data on star formation progression and stellar and gas distribution to better understand the process of bar quenching. We found that for three galaxies, the region between the nuclear or central sub-kiloparsec region and the end of the bar (bar region) is devoid of neutral and molecular hydrogen. While the detected neutral hydrogen is very negligible, we note that molecular hydrogen is present abundantly in the nuclear or central sub-kiloparsec regions of all four galaxies. The bar co-rotation radius is also devoid of recent star formation for three out of four galaxies. One galaxy shows significant molecular hydrogen along the bar, which might mean that the gas is still being funnelled to the centre by the action of the stellar bar. Significant star formation is also present along the bar co-rotation radius of this galaxy. The study presented here supports a scenario in which gas redistribution as a result of the action of stellar bar clears the bar region of fuel for further star formation and eventually leads to star formation quenching in the bar region. 2020 ESO. -
A space for the space theorist remembering henri lefebvre
Despite being somewhat ignored in Indian academia, Henri Lefebvre comes to our rescue every time, helping us understand and respond to spacetime challenges. 2020 Economic and Political Weekly. All rights reserved. -
Will mobile application technology help retail merchandising? Breakthrough innovation by FMCG companies
Forthe retail business to run successfully and to improve sales, the critical component is to display its products and services in a visually appealing manner. Retail merchandising assists the retailers to attract shoppers and influence their purchase. Often, the merchandising updates are not escalated up the hierarchy ladder as they are much dynamic and spontaneous in nature. Top manufacturing FMCG companies like HUL, ITC, etc. took up this challenge of modern trade merchandising by maintaining manpower in organized retail stores to tap the cutting edge of competitive advantage. The key challenges of these merchandisers include - maintaining overall shelf health, frequency and consistency of restocking, tracking the competition actions in the store, eliminating the conflicting signages, remove broken displays, and display compliances. These FMCG companies have adopted a breakthrough innovation of mobile applications to overcome these challenges. This study is novel and investigated the sales performance improvement through mobile application technology. The research was conducted in two parts. Part 1 included structural interviews (one-on-one) with retail store managers and FMCG sales representatives. The results disclosed eight major attributes as store trend, competition update, personnel management, stock availability, demand creation, in-store visibility, new products launch and promo packs, and share of shelf to improve sales performance. Part 2 examined the significance of these eight factors through quantitative study by considering FMCG merchandisers as respondents. The study identified that competition update, stock availability, personnel management, in-store visibility, and share of shelf were significant factors that impacted sales performance in retail merchandising by utilizing mobile technology applications. 2020, Associated Management Consultants Pvt. Ltd.. All rights reserved. -
Development and validation of gaming disorder and hazardous gaming scale (GDHGS) based on the WHO framework (ICD-11 criteria) of disordered gaming
This study aimed to develop and validate a brief psychometric scale for gaming disorder and hazardous gaming based on the WHO framework as defined in the ICD-11. The study was carried out among college students using face to face interview. A panel of mental health experts examined the face validity of the new Gaming Disorder and Hazardous Gaming Scale (GDHGS). An Exploratory Factor Analysis (EFA) using the principle component analysis (PCA) method with direct oblimin rotation on the five items of GDHGS was used for assessment of construct validity. The results of Kaiser Meyer Olkin (KMO) measure used for sampling adequacy and Bartlett's test (BT) of sphericity used to show the appropriateness of using factor analysis, confirmed the appropriateness of EFA for the present study sample. The factor analysis extracted single component with an eigenvalue of greater than one, which was further supported by the examination of scree plot. To examine the criterion related validity of the GDHGS, correlation between GDHGS and IGDS-SF scores was assessed. Spearman correlational analysis showed strong positive correlation of GDGHS score with IGDS-SF score (rs = 0.878, p < 0.01). Further, the sum of first four item score of GDHGS among participants diagnosed with GD (median: 15.00; IQR: 15.0015.75) was significantly greater than those without GD (median: 4.00; IQR: 3.006.50) according to the diagnostic interview based on the ICD-11 criteria (U = 0.000, p < 0.001). The internal consistency of GDHGS as measured by the Cronbach's alpha was 0.914. Further, the GDHGS did not have its reliability increased by removal of any of the five items included in the scale. Also, the threshold for significant floor and ceiling effect was not reached. In conclusion, GDHGS is a valid measurement scale for disorders involving gaming behaviour based on the ICD- 11 construct. 2020 Elsevier B.V. -
Secured and flexible user authentication protocol for wireless sensor network
Purpose: In wireless sensor network (WSN), user authentication plays as a vital role in which data sensing, as well as sharing, will be spoiled by hackers. To enhance user security, user authentication must be focused. Design/methodology/approach: In previous works, for secured authentication, Enhanced User Authentication Protocol (EUAP) is presented. On the other hand, the user free password generation is permitted in the previous technique. Findings: Here, password leakage may cause a malevolent user's contribution to the WSN environment. By presenting the Flexible and Secured User Authentication Protocol (FSUAP), this is solved in the presented technique in which secured as well as reliable sharing of data contents via unsecured wireless sensor devices was accomplished. Originality/value: The foremost objective of the present technique is to device the protocol that would verify the users beforehand letting them access the sensor devices situated in various sites. The use of a sensor device could be reduced in a significant way. Three-factor authentication protocols are presented in place of two-factor authentication protocol in the presented technique that could deal with and safeguard the environment from a brute force attack in an effective manner. 2020, Emerald Publishing Limited. -
Prob(E)abilities for enhanced research and interdisciplinarity: An exploration of innovative practices in english studies, languages, and media
An analysis of the history of research as well as contemporary trends in higher education in India reveals the predominance of scientific research. Public policies, developmental strategies, and market forces often determine the nature and output of research in humanities and social sciences. Research in literatures, languages, and media needs articulationa process that reveals the significant interdisciplinary interventions that can be brought to the process of research and highlights the need for purpose-driven research as research rather than need-based research for research. This paper offers a critical overview of the role of research in universities in India, contemporary approaches to research at the national level, and the need to engage in interdisciplinary, collaborative, and action-based research, especially in humanities and social sciences departments in universities across India. Further, the paper offers a few examples of interdisciplinary and collaborative research to highlight the need for a symbiotic approach to academic research. 2020 IUP. All Rights Reserved. -
Celebrity endorsements the interplay between intellectual property law and the consumer protection act, 2019
The ambit of Copyright law has expanded over time, leading to development of newer concepts such as, Personality Rights. These rights are vested in individuals who have acquired an identifiable persona in the eyes of the public. There are two important facets to personality rights-Right to Publicity &Right to Privacy. When such identifiable identities use their acquired celebrity status to promote goods and services of a company to attract more consumers, it can be understood as Celebrity Endorsements. This is the most common source of marketing used by major companies to increase sales and garner goodwill and reputation. However, this source of communicating necessary information to the public becomes dangerous when celebrities promote false or misleading advertisements. To counter such issues, the Consumer Protection Act, 2019 introduced provisions tohold celebrities endorsing such products or services to be liable for injury suffered by consumers. The Law mandates that in order to ensure that such misleading advertisements arent promoted, the celebrities must conduct due diligence of the products before endorsing them. However, the question remains that to what extent can celebrities, who are not directly involved in production or manufacturing, be held liable for exploiting their personality rights? This paper aims at addressing the newly created legal interlink between personality rights via celebrity endorsements and protection of consumer interests. 2020, National Institute of Science Communication and Information Resources. All rights reserved. -
Examining the effect of explicit instruction on vocabulary learning and on receptive-productive gap: An experimental study
This research study emphasized the importance of explicit instruction and repeated exposure to the target vocabulary for effective reception and production of new words among the second language learners of English. The purpose of the study was to examine the efficacy of the researcher- created supplementary for the prescribed set of vocabulary in the English language textbook. The study aimed to find out the amount of influence the explicit instruction and repeated exposure to the target vocabulary had on the nature of the receptive- productive gap. A total of sixty-two sixth grade students from a Government school in Tamil Nadu, India, participated in the experimental study which was conducted over a period of three months. The results of the study showed that the explicit instruction and repeated exposure to the target vocabulary had a significant amount of influence on vocabulary knowledge when compared to the conventional way of vocabulary instruction. In the conventional mode of vocabulary instruction, reception of vocabulary was found to have an average of 8% influence on the production knowledge, whereas in the case of the experimental group, it amounted up to 72%. This analysis showed that through explicit instruction and repeated exposure to the target vocabulary the receptive- productive gap is significantly reduced. 2020 JLLS and the Authors - Published by JLLS. -
Eccentricity splitting graph of a graph
Let G = (V, E) be any connected graph with (Figure presented.) for all uj, uk ? Si if e(uj) = e(uk)(1 ? i ? t) with each | Si |? 2 and (Figure presented.). The eccentricity splitting graph of a graph denoted by ES(G) is obtained by taking a copy of G and adding vertices w 1, w 2, , wt such that wi is adjacent only to the vertices of Si for 1 ? i ? t. We initiate the study on eccentricity splitting graph ES(G) and examine its structural properties. We also analyze diameter, girth and chromatic number of eccentricity splitting graphs of certain classes of graphs. 2021 Taru Publications. -
Luminescence and energy storage characteristics of coke-based graphite oxide
The substantial escalation in both energy consumption and ecological crisis prompts the utilization of conventional pollution-causing energy resources towards a proficient mode of energy production and storage. The most polluting fossil fuel like coal possesses a highly ordered sp2 carbon clusters, that can be easily tailored into graphene derivatives promising for energy-related applications. However, the impact of crystallinity and quality of the precursor coke on the physicochemical characteristics of extracted carbon nanostructures need to be identified. Herein, we have prepared graphite oxide structures (GrO) from high-quality coal, coke via Improved Hummers' method eliminating the need for toxic NaNO3. The inherent defect states own by coke are also of high significance as it performs the role of various photoluminescence emission centers. The sp2 domains and different surface defects promote excitation independent and dependent luminescence substantiating the distinct multi-emission property of GrO. The extent of functionalization during the oxidation process has also significantly affected the thermal stability of the carbogenic structure. The symmetric galvanostatic charge-discharge curves and lower internal resistance present superior stability and fatser ion transport of as-synthesized GrO. A specific capacitance of 193F/g was obtained at 0.2A/g with excellent capacitance retention over 2500 cycles. The versatile attributes of the coke derived GrO validate its realizable optoelectronics and energy storage applications. 2020 Elsevier B.V. -
PEVRM: Probabilistic Evolution Based Version Recommendation Model for Mobile Applications
Traditional recommendation approaches for the mobile Apps basically depend on the Apps related features. Now a days many users are in quench of Apps recommendation based on the version description. Earlier mobile Apps recommendation system do not handle the cold start problem and also lacks in time for recommending the related and latest version of Apps. To overcome this issues, a hybrid Apps recommendation framework which is considering the version of the mobile Apps is proposed. This novel framework named 'Probabilistic Evolution based Version Recommendation Model (PEVRM)' integrates the principles of Probabilistic Matrix Factorization (PMF) with Version Evolution Progress Model (VEPM). With the help this novel recommendation algorithm, the mobile users easily identify the specific Apps for particular task based on its version progression. At same time, this framework helps in resolving cold start problems of new users. Evaluations of this framework utilize a benchmark dataset, i.e., Apple's iTunes App Store3, for revealing its promising performance. 2013 IEEE. -
COVID-19: Trend analysis for market arrival of green gram in India
The unprecedented crisis hovering over the world due to Covid-19 pandemic has structurally impacted every sector of the world economy. This paper attempts to study the impact of ongoing pandemic in the agricultural sector specific to pulses in India. This paper finds that there is a significantly negative impact of Covid-19 on the pulses market. The market arrival of pulses has declined in the recent period while market demand for pulses has increased, therefore, there exists a supply side shortage for pulses in the domestic economy of India. This paper suggests that Government of India (Agriculture Department) urgently needs to deal with this shortage in supply of domestic pulses in "mandis" (agricultural markets). In this paper market arrival for pulses particularly green gram (Moong whole) has been forecasted for the next few months in Indian Agricultural Markets with the forecasting techniques such as Auto Regressive Integrated Moving Average (ARIMA) model and Artificial Neural Network (ANN) technique for pre and during pandemic period by using the arrival data in agriculture markets of India from Agmarknet. The results of this study using ARIMA models and ANNs have been compared to obtain the final conclusions with higher visibility in forecasting performance, which shows that there will be a sharp decline in market arrival with an average arrival of 494 quintals per day which can be maximized up to 623 quintals per day by stimulating the modal price at maximum possible point. Therefore, the urgent need of upscaling the technical efficiency of the farmers in different agro-climatic zones is needed to meet the domestic demand with domestic supply. 2020 DAV College. All rights reserved. -
Optical spectroscopy of Galactic field classical Be stars
In this study, we analyse the emission lines of different species present in 118 Galactic field classical Be stars in the wavelength range of 3800-9000 We re-estimated the extinction parameter (AV) for our sample stars using the newly available data from Gaia DR2 and suggest that it is important to consider AV while measuring the Balmer decrement (i.e. D34 and D54) values in classical Be stars. Subsequently, we estimated the Balmer decrement values for 105 program stars and found that ?20 per cent of them show D34 ? 2.7, implying that their circumstellar disc are generally optically thick in nature. One program star, HD 60855 shows H? in absorption - indicative of disc-less phase. From our analysis, we found that in classical Be stars, H? emission equivalent width values are mostly lower than 40 which agrees with that present in literature. Moreover, we noticed that a threshold value of ?10of H? emission equivalent width is necessary for FeII emission to become visible. We also observed that emission line equivalent widths of H?, P14, FeII 5169, and OI 8446for our program stars tend to be more intense in earlier spectral types, peaking mostly near B1-B2. Furthermore, we explored various formation regions of Ca II emission lines around the circumstellar disc of classical Be stars. We suggest the possibility that Ca II triplet emission can originate either in the circumbinary disc or from the cooler outer regions of the disc, which might not be isothermal in nature. 2021 Oxford University Press. All rights reserved. -
A new stepwise method for selection of input and output variables in data envelopment analysis
Data envelopment analysis (DEA) is one of the widely accepted optimization technique uses to measure the relative efficiency of organizational units where multiple inputs and outputs are present. The significance of DEA results depends on the variables selected for DEA modelling. One of the main challenges in data envelopment analysis modelling is of identify the significant input and output variables for DEA modelling. In this study, we propose an enhanced stepwise method to identify the significant and insignificant input and output variable by reducing the iterations process in stepwise method. The statistical significance of the input and output variables evaluated using the statistical methods: Least significance difference (LSD), and Welchs statistics. The proposed method applied to the Indian banking sector and the results have shown that the proposed model significantly identified the significant and insignificant input and output variables with least loss of information. 2021 the author(s).