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UVIT view of NGC 5291: Ongoing star formation in tidal dwarf galaxies at ? 0.35 kpc resolution
NGC 5291, an early-type galaxy surrounded by a giant H I ring, is believed to be formed from collision with another galaxy. Several star forming complexes and tidal dwarf galaxies are distributed along the collisional ring which are sites of star formation in environments where extreme dynamical effects are involved. Dynamical effects can affect the star formation properties and the spatial distribution of star forming complexes along the tidal features. To study and quantify the star formation activity in the main body and in the ring structure of the NGC 5291 system, we use high spatial resolution FUV and NUV imaging observations from the Ultraviolet Imaging Telescope onboard AstroSat. A total of 57 star-forming knots are identified to be part of this interacting system out of which 12 are new detections (star forming complexes that lie inside the H I contour) compared to the previous measurements from lower resolution UV imaging. We estimate the attenuation in UV for each of the resolved star-forming knots using the UV spectral slope ?, derived from the FUV - NUV colour. Using the extinction corrected UV fluxes, we derive the star formation rate of the resolved star forming complexes. The extinction corrected total star formation rate of this system is estimated as 1.75 0.04 M? yr-1. The comparison with dwarf galaxy populations (BCD, Sm, and dIm galaxies) in the nearby Universe shows that many of the knots in the NGC 5291 system have SFR values comparable to the SFR of BCD galaxies. 2023 The Author(s). -
Open global shadow graph and its zero forcing number
Zero forcing number of a graph is the minimum cardinality of the zero forcing set. A zero forcing set is a set of black vertices of minimum cardinality that can colour the entire graph black using the colour change rule: each vertex of G is coloured either white or black, and vertex v is a black vertex and can force a white neighbour only if it has one white neighbour. In this paper we identify a class of graph where the zero forcing number is equal to the minimum rank of the graph and call it as a new class of graph that is open global shadow graph. Some of the basic properties of open global shadow graph are studied. The zero forcing number of open global shadow graph of a graph with upper and lower bound is obtained. Hence giving the upper and lower bound for the minimum rank of the graph. 2023, Proyecciones. All Rights Reserved. -
Injective coloring of complementary prism and generalized complementary prism graphs
The complementary prism Gof a graph G is the graph obtained by drawing edges between the corresponding vertices of a graph G and its complement. In this paper, we generalize the concept of complementary prisms of graphs and determine the injective chromatic number of generalized complementary prisms of graphs. We prove that for any simple graph G of order n, ?i(G ? n and if G is a graph with a universal vertex, then ?i(G = n. 2020 World Scientific Publishing Company. -
Innovation and Progress: An Insight into the Indian Business Start- Ups and the Promotion of Scientific Temper for Socio-Economic Advancement
The Constitution of India through its 42nd Amendment of 1976, incorporated scientific temper' as one of the Fundamental Duties to every Indian citizen under Article 51 A (h). The first Prime Minister of India, Pandit Jawahar Lal Nehru mentions this term in his book Discovery of India where he characterized scientific temper as a mind-set to change or alter one's intuition in the light of evidences and not to accept anything which appears to be irrational or without proof. Our country has consistently put forth attempts to concede to the scientific temper, time and again and emphasised its significance. In 2013, the Science, Technology, and Innovation policy, developed by the Government of India pushed on the advancement of scientific temper amongst every citizen. However, it needs to go quite far to appropriately show this temperament while fostering the resolutions for achieving socio-economic goals of the country. Presently, it has been noticed that business ventures are intensely reliant uponscientific temper and this will be ultimately essential for the entrepreneurs to succeed. Thus, small and micro undertakings backed by competitive and state of the art technology will be the foundation for greater enterprises in the country, resulting in economic boom. All future businesses will be driven by science and technology and hence, it is called for addition of new avenues and enterprises, with changing time and further with scientific temper as its major ingredient. Start-ups can be considered as one such innovation that has been leading businesses growing by leaps and bounds. In India, the last decade emerged with great start-ups like CRED, Meesho, Swiggy, Zomato, Delhivery, Oyo and many more, making itself one of the most important start-up hubs in Asia and perhaps even in the world. The scientific temper in start-ups can further do wonders to Indias socioeconomic growth in the long run. Hence, in this paper, the authors shall make an attempt to bring out the essence of scientific temper in bringing forth the technologically advanced start-ups in India and its capacity to form the basis of India's future in the global market, in terms of both technological advancements and entrepreneurship. The paper will also highlight the hindrances to its growth and suggest measures in contributing to the growth of start-up ecosystem in India. 2024, Department of Law, University of North Bengal. All rights reserved. -
Impact of visual merchandising on consumers' purchase decision in apparel retail /
International Journal of Business and Administration Research, Vol.2, Issue 6, pp.271-279, ISSN No: 2348-0653. -
A Study on Laptop Brand Preferences in B-Schools
Volume : 2 | Issue : 12 | Dec 2013 • ISSN No 2277 - 8160 -
Influence of product and place factors on consumer buying behavior in formal footwear sector /
International Journal of Management and Social Science Research Review, Vol.1, Issue 2, pp.354-362, ISSN No: 2349-6738 (Print) 2349-6746 (Online) -
The hope and the dilemma of the urban poor
A common view about economically weaker sections and lower-income groups in India is that they live in slums because they cannot afford to buy or rent decent accommodation in the formal market. However, some can pay a monthly rent and/or for the services such as garbage disposal and water, but they, and others who can afford to buy, are deterred by institutional constraints. Many slum households face a dilemma: opting for better and more secure living conditions would mean losing some of the advantages of living in a slum and the possibility of a free home. 2018 Economic and Political Weekly. All rights reserved. -
Estimation of spectroscopic parameters and TL glow curve analysis of Eu3+-activated CaY2O4 phosphor
The solid-state reaction method was utilised to create a down-conversion phosphor in an air environment in CaY2O4:Eu3+ nanocrystalline material. The calcination temperature was set at 1000 C, and the sintering temperature was set at 1300 C. Following annealing, confirmation of the crystallinity quality of the phosphor was accomplished by the use of X-ray diffraction analysis. The particle size was predicted to be 43.113 nm using Scherrer's formula. To produce down-conversion luminescence spectra, an excitation wavelength of 247 nm was applied with a fluorescence spectrophotometer. The PL got increasingly intense as the concentration of the dopant increased. The maximum intensity was measured at 2.0 mol% of Eu3+ ion, which gradually decreased as the concentration increased because of concentration quenching. To analyse spectrophotometric peak determinations, the approach developed by the Commission Internationale de l'lairage (CIE) was used. Thermoluminescence (TL) glow curve analysis of the CaY2O4:Eu3+-doped phosphor manufactured here revealed a wide TL centred at 225 C, which comprised of so many peaks that may be extracted by the computerised glow curve deconvolution (CGCD) approach using glow-fit software. The associated kinetic parameters were then determined. The prepared phosphor may be useful for application in various display devices upon excitation by 247 nm; the prominent 613 nm peak of the Eu3+ ion (5D0 ? 7F2) electric dipole transition features a red component. CaY2O4:Eu3+ phosphors show promise as materials for potential use in phosphor-converted white LEDs in the field of solid-state lighting technology. The linear connection that the TL glow curve has with UV dose provides evidence for its possible use in dosimetry. 2023 The Royal Society of Chemistry. -
Synthesis of 4H-3,1-Benzothiazin-4-Ones via C-N/C-S Bond Forming Reactions
A Phosphine-free and effective process has been expressed for the formulation of N,S-heterocycles following a C-N/C-S bond forming reactions. The described process operates through EDC-HCl-mediated heterocyclization of diverse isothiocyanates and bis-nucleophiles to deliver 1,3-thiazinone derivatives, which eliminates the use of hazardous reagents. The developed protocol was found applicable over a wide range of substrates in delivering N,S-heterocycles in excellent yields at room temperature and short reaction time. 2022 Taylor & Francis Group, LLC. -
Improved Photocatalytic Activity of g-C3N4/ZnO: A PotentialDirect Z-Scheme Nanocomposite
In this study, a Z-scheme g-C3N4/ZnO nanocomposite was synthesized using exfoliation process, which was further characterized using XRD, FT-IR, UV-DRS, SEM-EDAX, PL, EIS, and TGA techniques. The properties of g-C3N4 were enhanced when fabricated with ZnO resulting in a better electron mobility, high redox potential, and excellent semiconducting properties. The performance of this heterostructure was evaluated by photocatalytic degradation of malachite green (MG) under visible light irradiation. The g-C3N4/ZnO heterostructure achieved a degradation of 84.3 % within 60 min under visible light irradiation. The degradation reaction follows a pseudo first-order kinetic model with a reaction rate constant of 0.0329 min?1. The nanocomposite demonstrated outstanding stability and recyclability. 2020 Wiley-VCH GmbH -
Exploring the potential application of Cr2AlC MAX phase as an emerging electrocatalyst for overall water splitting
A three-dimensional (3D) chromium carbide ceramic type, H-phase (211) categorized as Cr2AlC, MAX phase has garnered enormous attention in recent times due to its unique structure and bonding, surface area, thermal stability, and thermo-electrical conductivity, and hydrophilicity. A simple synthesis approach is proposed for obtaining layered Cr2AlC, MAX phase, with X-ray diffraction data and SEM morphology confirming the formation of the H-phase. The electrocatalyst Cr2AlC is being utilized for electrocatalytic water splitting application. The Cr2AlC is observed to exhibit an overpotential and Tafel slopes of 215 mV/88.3 mV dec? 1 for the hydrogen evolution reaction (HER) and 376 mV/96.5 mV dec? 1 for the oxygen evolution reaction (OER), respectively, demonstrating good stability for up to 7200s. This study establishes a straightforward method for producing emergent material, Cr2AlC MAX phase, and highlights its promising applications in water electrolysis, hydrogen evolution, and oxygen evolution reactions. Qatar University and Springer Nature Switzerland AG 2024. -
A constrained multi-period portfolio optimization model based on quantum-inspired optimization
Multi-period portfolio optimization (MPO) is one of the most important problems to be solved to help investors select optimal portfolios for investment plans. The portfolios are influenced by the risk factors in the market and it is important to select optimal portfolios that can maximize the returns with minimum risk values. Other than the risk factor, there are several other influential factors that reduce the optimality of the portfolios. Therefore, by considering all possible constraints, this study proposes a multi-constraint MPO model that selects the optimal portfolio based on the asset returns. To solve the multi-constrained problem, a novel quantum-inspired whale optimization algorithm (QWOA) is introduced in this paper. The proposed algorithm enhances the traditional optimization model to work in a multi-constrained scenario. Here, quantum entanglement is adapted to reduce the slow convergence issue of whale optimization. Apart from considering only the risk factors, this paper also considers certain higher-order moments (HOM), such as skewness, kurtosis, transaction cost, diversification, boundary and budget constraints. These factors affect the portfolios as the market is dynamic, and timely changes are always seen. Thus, optimizing the mentioned factors aids in attaining an optimal portfolio. Empirical evaluations are performed, and the results suggested that the proposed model provided beneficial outcomes as compared with other algorithms like whale optimization algorithm (WOA), gray wolf optimization (GWO), fruitfly optimization algorithm (FOA), particle swarm optimization (PSO) and fruitfly algorithm (FA). The overall net return rate of the proposed model is always above 0.85% for different values of upper bounds, and the obtained Sharpe ratio, Sortino ratio, STARR ratio, information ratio, Shannon entropy, and downside deviation values of the proposed algorithm are 5.016254, 0.89327, ? 0.01987, 0.103826, 3.04452 and 0.2854. Hence, the proposed approach is highly effective for optimizing the constrained MPO. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Salvia officinalis L. resilience under chromium stress: An integrated study of growth, physiology, biochemical changes and rosmarinic acid production
Medicinal plants are increasingly challenged by rising chromium (Cr) levels in agricultural soil and water bodies due to industrialization and human activities. This research examines the impact of various chromium concentrations on Salvia officinalis L., a medicinal herb, over 3 specific time periods: 30, 60 and 90 days. As the duration of Cr exposure increases, various growth parameters showed an upward trend at the lowest concentrations, with the most robust growth observed in the 20 ppm Cr treatment group after 90 days. However, higher chromium concentrations resulted in reduced plant growth compared to untreated plants. Chromium primarily accumulates in the roots, stems and leaves, with the highest accumulation observed at 100 ppm. However, chlorophyll content declined with prolonged Cr exposure, particularly at higher concentrations. Carbohydrate levels initially increased at lower Cr concentrations but decreased with greater exposure, while protein content consistently decreased with elevated Cr levels. Proline levels exhibited mixed responses, rising at lower concentrations and declining at higher ones. Malondialdehyde (MDA) content increased with higher Cr levels and extended exposure. The enzymatic antioxidant system showed an initial increase followed by a decline with prolonged exposure. Rosmarinic acid content increased with chromium (Cr) exposure upto 60 ppm but subsequently decreased beyond that threshold. In the first 30 days, plants treated with Cr demonstrated a 17 % increase in rosmarinic acid production compared to the control (48.9 mg/g DW). However, with continued Cr exposure, there was a decline in rosmarinic acid production ranging from 10 % to 20 % compared to the control level (67.02 mg/g DW) at 90 days post-treatment. These findings underscore the complex and contrasting responses of Salvia officinalis to Cr toxicity, highlighting the necessity for extended study into the core mechanisms governing these responses and the development of strategies to alleviate heavy metal stress in plants. The Author(s). -
The accumulation, antioxidant defences, and secondary metabolite production in common sage (Salvia officinalis L.) under lead toxicity
The growing levels of lead (Pb) in agricultural soil and water bodies as a result of industrialization and human activity present serious challenges for medicinal plants. The present study investigates the complex responses of Salvia officinalis to toxicity caused by Pb including metal accumulation, translocation dynamics, antioxidant defenses, and the production of secondary metabolites. Pb showed preferential accumulation in the roots, peaking at (1000 ppm Pb) (2484.2 mg kg-1). The reduced levels of total chlorophyll (1.29-fold), protein (1.9-fold), and carbohydrate (2.5-fold) under prolonged exposure to stress demonstrate the toxic impacts of lead. Proline and total phenolic content (TPC) increased concentration-dependently under lead stress, while flavonoids were found to be decreased with the enhancement of lead toxicity. Enzymatic antioxidants (catalase, APX, and SOD) showed notable increase, especially in the 30 days of treatment, demonstrating the plants strong defenses. S. officinaliss adaptive responses were highlighted by concentration-dependent increases in non-enzymatic antioxidants such as total antioxidant capacity (TAC) and DPPH radical scavenging activity. Crucially, under lead stress, S. officinalis showed 1.7-fold increased rosmarinic acid (RA) production, in plants exposed to 200 ppm for 30 days treatment. However, further exposure to lead significantly caused the reduction of RA production. The results add to our knowledge of how sage plants respond to environmental stress and offer important insights for future uses in phytoremediation and the breeding of stress-tolerant plant cultivars. Furthermore, the research highlights about the S. officinaliss potential as a source of bioactive compounds possessing antioxidant qualities, under low levels of lead stress. 2024, Indian journals. All rights reserved. -
Identification of broken characters in degraded documents
Optical Character Recognition (OCR) deals with the recognition of characters in a text document. Steps like Preprocessing, Segmentation and Recognition are embedded in the OCR machine. When a document is scanned it will be taken into OCR and will recognize the characters. But noisy scanning of documents, low-quality printed documents and thresholding error leads to the generation of broken characters. When these documents are given as inputs into OCR, the recognition becomes a tedious process since the broken characters are misunderstood by the OCR machine. So the broken characters have to be identified and segmented separately. This work aims to enhance the degraded documents with broken characters using image processing techniques. For identifying or recognizing the broken character from the image various techniques like vertical projection profile, horizontal projection profile, chain code, mean based thresholding are used. The lines from the document are separated using line segmentation. Separate characters are extracted using Vertical Projection Profile and Horizontal Projection Profile. The character is identified using chain coding. The broken characters are found from them using Mean-based Thresholding and is merged using Heuristic information. The proposed method achieves an accuracy of 92.88% and also performs well for color image documents as well as black and white image documents also because of the effective preprocessing. 2018 Intelligent Network and Systems Society. -
High gain ultra wideband fractal antenna
A high gain Compact Octagonal Ultra-wideband Fractal Antenna (COUFA) using the Dual Layer Meta Frequency Selective Surface Reflector (DLMFSSR) is presented in this manuscript. The proposed Frequency Selective Surface (FSS) provides a suitable reflection phase to act as a reflector and is capable of enhancing the gain of the antenna in its wide operating bandwidth. The proposed antenna design provides better impedance bandwidth of 2-10.37 GHz with significant increase in the gain of 0.41-11.83 dB at various resonance frequencies in comparison with the antenna without reflector. The complete antenna with DLMFSSR is designed and simulated using High Frequency Structure Simulator (HFSS). The Proposed antenna, FSS are fabricated and the numerical results for return loss S11, VSWR and gain are demonstrated. Simulation and fabrication results are found to be worthy, which suites the design malleable enough for several modern UWB wireless applications. Copyright 2019 American Scientific Publishers All rights reserved. -
Mutual Information Pre-processing Based Broken-stick Linear Regression Technique for Web User Behaviour Pattern Mining
Web usage behaviour mining is a substantial research problem to be resolved as it identifies different user's behaviour pattern by analysing web log files. But, accuracy of finding the usage behaviour of users frequently accessed web patterns was limited and also it requires more time. Mutual Information Pre-processing based Broken-Stick Linear Regression (MIP-BSLR) technique is proposed for refining the performance of web user behaviour pattern mining with higher accuracy. Initially, web log files from Apache web log dataset and NASA dataset are considered as input. Then, Mutual Information based Pre-processing (MI-P) method is applied to compute mutual dependence between the two web patterns. Based on the computed value, web access patterns which relevant are taken for further processing and irrelevant patterns are removed. After that, Broken-Stick Linear Regression analysis (BLRA) is performed in MIP-BSLR for Web User Behaviour analysis. By applying the BLRA, the frequently visited web patterns are identified. With the identification of frequently visited web patterns, MIP-BSLR technique exactly predicts the usage behaviour of web users, and also increases the performance of web usage behaviour mining. Experimental evaluation of MIP-BSLR method is conducted on factors such as pattern mining accuracy, false positives, time requirements and space requirements with respect to number of web patterns. Outcomes show that the proposed technique improves the pattern mining accuracy by 14%, and reduces the false positive rate by 52%, time requirement by 19% and space complexity by 21% using Apache web log dataset as compared to conventional methods. Similarly, the pattern mining accuracy of NASA dataset is increased by 16% with the reduction of false positive rate by 47%, time requirement by 20% and space complexity by 22% as compared to conventional methods. 2020. All Rights Reserved. -
Co-sputtered V2O5TiN composite on Ag-network current collector for high-performance flexible transparent thin-film supercapacitors
Next-generation wearables require extremely capable electrochemical energy-storage devices that exhibit improved performance with high flexibility and transparency. Herein, we present a highly flexible and transparent electrochemical thin-film supercapacitor electrode fabricated by co-sputtering V2O5 and TiN on an Ag-network-based current collector. The electrodes' physical properties, optical properties, and structural morphologies are studied using X-ray diffraction, UVvisible spectroscopy, and scanning electron microscopy, respectively. A symmetric device is fabricated using V2O5 and TiN on an Ag network, and the TiN sputter power is varied to optimize the performance. The device performance of the co-sputtered electrodes at various composition ratios is studied. The optimized V2O5TiN (200?40)/Ag electrode device with pseudocapacitive behavior delivers an excellent areal specific capacitance of 98.66 mF cm2 at a current density of 4 mA cm2 with a charge retention of 90.12 % after 6000 cycles. The V2O5TiN (200?40)/Ag electrode device outperforms other reported electrodes, with an energy density and power density of 30.83 ?Wh cm2 and 2999.67 ?W cm2, respectively, and excellent mechanical stability. 2023 -
Statistical features learning to predict the crop yield in regional areas
The plethora of information presented in the form of benchmark dataset plays a significant role in analyzing and understanding the crop yield in certain regions of regional territory. The information may be presented in the form of attributes makes a prediction of crop yield in various regions of machine learning. The information considered for processing involves data cleaning initially followed by binning to reduce the missing data. The information collected is subjected to clustering of data items based on patterns of similarity, The data items that are similar in nature is fed to the system with similarity measure, which involves understanding the distance of data items from its related data item leading to hyper parameters for analyzing of information while calculating the crop yield. The information may be used to ascertain the patterns of data that exhibit similarity with nearest neighbor represented by another attribute. Thus, the research method has yielded an accuracy of 89.62% of classification for predicting the crop yield in agricultural areas of Karnataka region. 2022 Institute of Advanced Engineering and Science. All rights reserved.