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Investigating structure and spectral energy distribution of galaxies using uvit and multi-wavelength archival data
This thesis deals with the multi-wavelength investigation of the different aspects of galaxy formation and evolution. The first part of this thesis deals with the studies on the characteristics of the in-orbit performance of the Ultraviolet Imaging Telescope (UVIT) on-board AstroSat. We have written a UVIT pipeline (JUDE ) to convert the Level 1 data from the Indian Space Science Data Centre (ISSDC) into scientifically useful photon lists and images. We have also performed an independent calibration of the FUV and NUV channels of the UVIT using JUDE. We found that the photometric sensitivity is about 35% that of the Galaxy Evolution Explorer (GALEX ) in the FUV broadband filter, and about the same as GALEX in the NUV broadband filter. The point spread function (PSF) of the instrument is of the order of 1.2 1.6and#8242;and#8242;. We found that the performance is close to that expected from the ground-based calibrations. We studied the recent star formation in the nearby face-on spiral galaxy NGC 2336 using the UVIT imaging. We have identified 78 bright star-forming complexes in the disk and derived their positions and estimated their properties such as luminosities, sizes, star formation rates (SFRs), colors, and ages. The FUV-NUV colors of the complexes are found to be redder in the inner region of the galaxy and become progressively bluer as the radius increases. The last part of this thesis is devoted to a model-based study of galaxies using physically motivated Code Investigating Galaxy Emission (CIGALE) package. We have studied 10,000 galaxies from GALEX SDSS merged catalog using CIGALE and estimated their properties such as stellar masses, SFRs, stellar populations, dust luminosities etc. We have classified this set of galaxies into the star-forming, intermediate and quiescent type of galaxies based on their specific SFR. We also studied the properties of dust-lane spheroidal galaxies (DLSGs) drawn from the multi-wavelength archival data in 18 bands from FUV to FIR using GALEX, SDSS, 2MASS, WISE, and AKARI surveys. -
Investigating sustainable development for the COVID-19 vaccine supply chain: a structural equation modelling approach
Purpose: Immunization is one of the most cost-effective ways to save lives while promoting good health and happiness. The coronavirus disease 2019 (COVID-19) pandemic has served as a stark reminder of vaccines' ability to prevent transmission, save lives, and have a healthier, safer and more prosperous future. This research investigates the sustainable development (SD) of the COVID-19 vaccine supply chain (VSC). Design/methodology/approach: This study investigates the relationship between internal process, organizational growth, and its three pillars of SD environmental sustainability, economic sustainability and social sustainability. Survey-based research is carried out in the hospitals providing COVID-19 vaccines. Nine hypotheses are proposed for the study, and all the hypotheses got accepted. The survey was sent to 428 respondents and received 291 responses from health professionals with a response rate of 68%. For the study, the healthcare professionals working in both private and public hospitals across India were selected. Findings: The structural equation modelling (SEM) approach is used to test the hypothesis. All nine hypotheses are supported. This study examines a link between internal processes and organizational learning and the three sustainability pillars (environmental sustainability, economic sustainability and social sustainability). Practical implications: This study will help the management and the policymakers to think and adopt SD in the COVID-19 VSC. This paper also implies that robust immunization systems will be required in the future to ensure that people worldwide are protected from COVID-19 and other diseases. Originality/value: This paper shows the relationship between organizational learning and internal process with environmental sustainability, economic sustainability and social sustainability for the COVID-19. Studies on VSC of COVID-19 are not evident in any previous literature. 2022, Subhodeep Mukherjee, Manish Mohan Baral, Venkataiah Chittipaka, Surya Kant Pal and Ramji Nagariya. -
Investigating the contrast diurnal relationship of land surface temperatures with various surface parameters represent vegetation, soil, water, and urbanization over Ahmedabad city in India
Many climatic problems have arisen due to congested and inefficient planning, reduced vegetation cover, and increased pollution from factories and vehicles. One such primary concern is increased land surface temperature (LST) contributes to the urban heat island (UHI) occurrence. This research aims to understand better the UHI effect in the region neighbouring the Indian city of Ahmedabad. MODIS sensor data (onboard Aqua and Terra platforms) and Landsat data were used for the study. The research was done for the summer, monsoon, and winter seasons in the research region, using data from thirteen years between 2003 and 2015. The current study looked at LSTs' spatial and temporal differences to assess the SUHI effect over Ahmedabad city. The association between diurnal LST and various surface variables such as vegetation, built-up, soil, water, and so on has also been examined. A variety of land surfaces influences the diurnal variations of LSTs. The diurnal associations of LST with vegetation, urbanization, soil, and water factors have been studied. The overall study of LST' relationship with all of the various parameters reveals a very significant dynamic relationship. 2022 The Author(s) -
Investigating the Determinants of Financial Well-Being: A SEM Approach
Studies reveal that the financial well-being of employees has a direct bearing on their productivity and overall well-being. The wellness initiatives organized by the information technology (IT) companies operating in India have also started focusing on the contributing aspects of financial well-being. In this context, the article explores the determinants of financial well-being of IT professionals in India. The article utilizes confirmatory factor analysis (CFA) for the analysis. The study employs a survey questionnaire covering financial literacy, financial behavior, and financial fragility. It also attempts to recognize the influence of gender and job roles (technical or managerial) in ascertaining financial well-being. The sample data used in the study include 237 professionals employed in the IT sector. The study uses partial least squared structured equation modelling (PLS-SEM) to understand the connection between the determining factors. The results indicate that financial well-being is positively influenced by financial literacy and financial behavior while financial fragility has a substantial negative impact. The financial literacy and financial fragility are significantly different between technical and managerial roles. Gender appears to have a sizeable impact on the financial behavior and financial fragility levelswomen employees performed better in both the factors. Interestingly, financial literacy levels of the two genders are not significantly different. The results show that there is a need to focus on literacy, behavior, and fragility in financial wellness programs organized by the IT industry. Further, the study recommends offering tailored financial wellness training modules created based on the job levels and gender instead of following one program, fits all standardized approach. 2023 KJ Somaiya Institute of Management. -
Investigating the Dynamic Interlinkages between Exchange Rates and the NSE NIFTY Index
This study aims at examining the short-run and long-run dynamic linkages among exchange rates and stock market index in India through a structured cointegration and Granger causality tests. Daily exchange rates of USD, EUR, CNY, JPY, and GBP to INR along with the daily movement of NSE NIFTY for a period spanning 13 years from 6 September 2005 to 31 December 2018 were used for the analysis. The results reveal that there is no evidence for a stable long-run relationship between NSE NIFTY and the exchange rates under study. However, the VAR-based Granger causality test shows that USD, JPY, and CNY have short-run causal relationship with NSE NIFTY. The NSE NIFTY also seemed to have an influence on USD expressed in terms of Indian rupee. The impulse response analysis further supports the results of the Granger causality test and provides information on the time required for the NSE NIFTY index to recover from a shock caused by the fluctuation in exchange rates. 2021 by the authors. -
Investigating the dynamics, synchronization and control of chaos within a transformed fractional SamardzijaGreller framework
In this article, in response to the limitations of existing ecological models, we address the critical need for a more comprehensive understanding of predatorprey dynamics by presenting a modified fractional SamardzijaGreller model that incorporates intra- and inter-species competitions within two predator populations. Our model stands out for being more realistic because it considers the natural competition that occurs among and between two predator species when they share a common prey We derived the local stability conditions at equilibrium points using RouthHurwitz conditions for the modified model. With the help of a suitably chosen Lyapunov function, we also obtained the global stability condition for our fractional model. The existence of chaos has been confirmed through Lyapunov exponents and bifurcation in the new system for two distinct sets of initial conditions for different fractional orders. Employing the active control method, we establish conditions for synchronization between these two fractional systems and introduce control functions for chaos management in the modified model. Numerical simulations, utilizing the generalized AdamsBashforthMoulton method, support the theoretical findings across a spectrum of fractional orders ranging from 0 to 1. We demonstrated the adaptability of the active control method for different fractional orders. A fractional order of ? equal to 1 for synchronization shows rapid convergence, but a drop to ? equal to 0.80 causes a substantial slowdown that takes almost six times more number of iterations to complete. Thus, we shed light on how the fractional order of the system plays a pivotal role in determining the speed of synchronization, with lower orders leading to a noticeable delay and higher fractional orders favoring faster synchronization. Our thorough investigation contributes to the understanding of complex ecological systems and offers practical insights into fractional chaos control mechanisms within the context of predatorprey models. 2024 Elsevier Ltd -
Investigating the Impact of Emotional Contagion on Customer Attitude, Trust and Brand Engagement: A Social Commerce Perspective
Social Commerce networks are a powerful platform for spreading positive and negative emotional contagion, which is affecting users from different perspectives, i.e., psychology, attitude, buying decision. Emotional contagion is the phenomenon of having a person's emotions and behaviours directly trigger similar emotions or behaviour in other people. This research proposes a model to analyze the factors influencing emotional contagion that, in turn, impact consumer's attitudes, trust, and brand engagement. This study used a survey approach using a structured questionnaire. Primary data was collected from 174 social media users who shop online. The proposed model was tested using multiple regression analysis. The results demonstrated that effective content, visual or text, triggers customers' emotional contagion, influencing customer attitude and trust leading to brand engagement. The research study's findings can be used for deciding on content strategies of advertisements pertaining to social commerce. 2022 Academy of Taiwan Information Systems Research. All rights reserved. -
Investigating the in-flight performance of the UVIT payload on AstroSat
We have studied the performance of the Ultraviolet Imaging Telescope payload on AstroSat and derived a calibration of the far-ultraviolet (FUV) and near-ultraviolet (NUV) instruments on board. We find that the sensitivity of both the FUV and NUV channels is as expected from ground calibrations, with the FUV effective area about 35 per cent and the NUV effective area about the same as that of GALEX. The point spread function of the instrument is on the order of 1.2-1.6". We have found that pixel-to-pixel variations in the sensitivity are less than 10 per cent with spacecraft motion compensating for most of the flat-field variations. We derived a distortion correction but recommend that it be applied post-processing as part of an astrometric solution. 2018 The Author(s). -
INVESTIGATING THE ROLE OF UTAUT2 IN THE USER SATISFACTION AND CONTINUED USAGE OF MOBILE FITNESS APPS: EVIDENCES FROM INDIA
This study examines mobile fitness app (MFA) adoption and use using the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2). CB-SEM analysis of 445 respondents through IBM-AMOS was conducted. UTAUT2 constructs were examined including, consumer satisfaction, e-loyalty, and mobile fitness app reuse. Also, the roles of socio-demographic factors as control variables were examined. The results indicated that UTAUT2 significantly influenced user perception of MFAs. UTAUT2 constructs increased user satisfaction. User satisfaction positively and significantly influenced e-loyalty and app reuse. The study also suggests future research on UTAUT2's role on MFAs. The study highlights UTAUT2 by revealing the constructs that influence MFA adoption, and selected consequences. (2024), (Amity University). All rights reserved. -
Investigating the transport flexibility measures for freight transportation: a fuzzy best-worst method approach
Unpredicted disruptions force organisations to ensure flexibility for fulfilling customer demand. Enabling flexibility along the transportation system is the most suitable solution for unpredictable disruptions. Flexibility, being a potential element, requires more attention to gain competitive advantages. In this study, an effort has been made to investigate different transport flexibility measures (TFMs) related to freight transportation. Initially, an extensive literature survey is performed to identify different TFMs linked with the supply chain and logistics domain. Further, an integrated fuzzy best-worst method (FBWM) has been adopted to prioritise the identified TFMs and sensitivity analysis is performed to ensure robustness of the model. The findings of the study reflect mode, fleet, vehicle and speed flexibility as the significant flexibility measures for freight transportation. This study will help practitioners, managers and decision-makers associated with freight transportation to make better decisions to ensure flexibility in the freight transportation system. Copyright 2022 Inderscience Enterprises Ltd. -
Investigating the Use of Natural Language Processing in Electronic Medical Record
Natural language processing (NLP) implemented in digital scientific records (EMRs) can substantially enhance the nice and efficiency of affected person care. The purpose of NLP implemented in EMRs is to extract applicable facts from affected persons' notes written in a human language together with English. This information can then be stored in a suitable structured form for further evaluation and records mining. NLP has been carried out in the clinical field for the reason that Fifties as a green approach for retrieving textual content-based data and reading interactions among affected persons and healthcare professionals. With the arrival of electronic facts, NLP has come to be extra extensively applied for the diffusion of purposes, inclusive of automatic coding, scientific choice aid, and medical doctor order access. This summary makes a of exploring the usage of NLP in EMRs. The scope of this research consists of an evaluate of present NLP technologies and their software in EMRs. It additionally outlines a number of the present-day demanding situations inside the use of NLP for clinical information and shows capability answers. Finally, the potential applications of NLP-driven EMRs are discussed, inclusive of making use of in-health practitioner order entry, scientific choice assistance, and population health control. 2024 IEEE. -
Investigation into the Mechanical, Fatigue and Superplastic Characteristics of Shape Memory Alloys (SMA) in CuAlMn, CuAlBeMn, and CuAlFeMn Compositions and Their Composite Variants
Shape memory alloys (SMAs) exhibit high sensitivity to compositional changes in terms of their super elasticity, shape memory effect, and transition temperatures. A deeper comprehension of SMA composition and its impact on mechanical properties can be attained by differential scanning calorimetry. The current study uses experimental work to assess the energy absorption capacity, mean fracture width, residual strength, and cracking strength of samples made of short shape memory alloy (SMA) fibers that are randomly distributed on the specimens tensile side. In this investigation, three samples were synthesized based on the Cu, Al, and Mn proportions found in CuAlMn shape memory alloys (SMA1, SMA2, and SMA3). Moreover, three samples with different ratios of Cu, Al, Mn, Be, and Fe were synthesized for the shape memory alloys CuAlBeMn and CuAlFeMn (SMA2, and SMA3). The synthesized CuAlMn, CuAlBeMn, and CuAlFeMn SMA alloys showed good strain recovery, ranging from 90 to 95%. The martensite that forms and changes when the alloys are heated and quenched mostly controls the strain recovery by the corresponding SMAs. SMA 2 of the CuAlBeMn has a greater strain recovery rate, rising by 8.5% and 44.38%, respectively, in comparison to SMA 1 and SMA 3. CuAlBiMn shape memory alloys demonstrated superior super elasticity and martensite stability in comparison to SMA 1 and SMA 2 respectively. SMA 1 and SMA 2 demonstrated greater residual strength, cracking strength, and energy absorption capacity for all fiber volume fractions. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024. -
INVESTIGATION OF ANTECEDENTS AND CONSEQUENCES OF USEFULNESS IN ONLINE TRAVEL COMMUNITIES: THE MODERATING ROLE OF DECISION MAKING STAGE
This study examines the perceived usefulness (PU) of online discourse and the decision-making behavior of users in Online Travel Communities (OTCs). Partial least squares structural equation modeling (PLS-SEM) was used on secondary data available in OTCs in the form of 852 threads to empirically test the proposed integrated model. The antecedents of the perceived usefulness of online travel communities were found to be the argument quality and credibility. These influence the PU of user-generated content significantly and are helpful in information adoption in OTCs. The PU of OTC discourse positively impacts travelers' information adoption and decision-making. The current study offers implications for OTCs and online service providers for enhancing the usefulness of user-generated content in OTCs and social media sites, leading to online information use and travel decision-making. Prior literature has explored the nature and magnitude of the influence of electronic word-of-mouth (eWOM) on information adoption and intention to use information for travel purchases from users' perspectives and has investigated the PU of third-party travel sites. This paper is an effort to examine PU and decision-making by analyzing the User-Generated-Content (UGC) posted by the actual users. 2023 Akdeniz University Publishing House. All rights reserved. -
Investigation of Brain Tumor Recognition and Classification using Deep Learning in Medical Image Processing
A brain tumour is the growth of brain cells that are abnormal, some of which may progress into cancer. Magnetic Resonance Imaging (MRI) scans are the method used most frequently to detect brain tumours. The brain's abnormal tissue growth can be seen on the MRI images, which reveal. Deep learning and machine learning techniques are employed to identify brain tumours in a number of research publications. It only takes a very short amount of time to predict a brain tumour when these algorithms are applied to MRI images, and the increased accuracy makes patient treatment simpler. Thanks to these forecasts, the radiologist can make quick decisions. The suggested approach employs deep learning, a convolution neural network (CNN), an artificial neural network (ANN), a self-defined neural network, andthe existence of brain tumor. 2022 IEEE. -
Investigation of Cervical Cancer Detection from Whole Slide Imaging
Early cancer detection is critical in enhancing a patient's clinical results. Cervical cancer detection from a large number of whole slide images generated regularly in a clinical setting is a complex and time-consuming task. As a result, we require an efficient and accurate model for early cancer diagnosis, especially cervical cancer as it can be fully prevented if detected in an early stage. This study focuses on in-depth writing on current methodologies for cervical cancer segmentation and characterization from the whole cervical slide. It combines the state of their specialty's performance measurement with the quantitative evaluation of cutting-edge techniques. Numerous publications over the last eleven years (2011-2022) clearly outline various cervical imaging methods over multiple blocks. And this review shows different types of algorithms used in each processing stage of detection. The study clearly indicates the advancements in the automation field and the necessity of the same. Published under licence by IOP Publishing Ltd. -
Investigation of corrosion behavior of Cenosphere reinforced iron based composite coatings
In the present study cenopshere was reinforced with FeCrNiC (Metco 42C) as matrix material and prepared four different feedstock powders such as FeCrNiC+0%Cenosphere, FeCrNiC+5%Cenosphere, FeCrNiC+10%Cenosphere and FeCrNiC+15%Cenosphere were coated by plasma spray technique on T22 substrate. Evaluation of the substrate and coatings potential under salt spray test was performed. Dense fog of 5% NaCl salt water was used to create a corrosive atmosphere within the chamber. The salt water's pH was kept constant at 6.57. The materials that underwent corrosion were examined using X-ray diffraction (XRD), and scanning electron microscopy (SEM). The FeCrNiC+15%Cenosphere and FeCrNiC+10%Cenosphere coatings exhibited reduced weight loss during a 168-h corrosion test compared to the FeCrNiC+5%Cenosphere, FeCrNiC coatings, and substrate. The excellent chemical stability and corrosion resistance of Cr23C6, SiO2, NiO, and Cr2O particles contribute to gradually avoid the formation of red rust on Fe-based coated samples with exposure approaches to 52 and 130 h. 2024 The Authors -
Investigation of detoxification nature of activated carbons developed from Manilkara zapota and de oiled soya
Heavy metals are poisonous and detrimental water contaminant. Their existence affects human beings, animals and vegetation as a outcome of their mobility in aqueous ecosystem, toxicity and nonbiodegradability. This work aimed at the development of new adsorbent in the detoxification of heavy metals using Manilkara zapota tree wood and de oiled soya. The study completely focused on the characterization of the developed activation in the view of using it as a adsorbent. The characterization of activated carbon was effected SEM analysis, FTIR, XRD analysis and surface area determination. Both the activation carbon have showed a tremendous characterization in their employability as adsorbent in adsorption of heavy metals in aqueous solution. 2019 Elsevier Ltd. All rights reserved. -
Investigation of dielectric properties of indigenous blended ester oil for electric system applications
The insulation condition of a transformer decides the longevity of the equipment. The unpredicted failure of power transformer will lead to major disaster in the distribution network and it affects both environment and public safety. Nowadays synthetic oil and natural esters are alternatives to transformer oil because of the biodegradable nature. In this paper, investigations were carried out to study the performance of the blended ester. The different properties investigated were viscosity, breakdown voltage, flash point, dielectric dissipation factor and moisture content. Comparisons of the properties were made between mineral oil, vegetable oil without additives and with additives. Further Investigation was carried out to study the impact of antioxidants and degasification. The results indicated that the addition of antioxidants and degasification of the vegetable oil improve significantly its voltage withstanding capacity. The Indigenous oil is code named as DM; Indigenous oil with DBPC is codenamed as DM1, Indigenous oil with BHA is codenamed as DM2. The results have been tabulated and found to be satisfactory. 2020 ASTES Publishers. All rights reserved. -
Investigation of efficient multilevel inverter for photovoltaic energy system and electric vehicle applications
Introduction. This research presents a simple single-phase pulse-width modulated 7-level inverter topology for renewable system which allows home-grid applications with electric vehicle charging. Although multilevel inverters have appealing qualities, their vast range of application is limited by the use of more switches in the traditional arrangement. As a result, a novel symmetrical 7-level inverter is proposed, which has the fewest number of unidirectional switches with gate circuits, providing the lowest switching losses, conduction losses, total harmonic distortion and higher efficiency than conventional topology. The novelty of the proposed work consists of a novel modular inverter structure for photovoltaic energy system and electric vehicle applications with fewer numbers of switches and compact in size. Purpose. The proposed system aims to reduce switch count, overall harmonic distortions, and power loss. There are no passive filters required, and the constituted optimizes power quality by producing distortion-free sinusoidal output voltage as the level count increases while reducing power losses. Methods. The proposed topology is implemented with MATLAB/Simulink, using gating pulses and various pulse-width modulation methodologies. Moreover, the proposed model also has been validated and compared to the hardware system. Results. Total harmonic distortion, number of power switches, output voltage, current, power losses and number of DC sources are investigated with conventional topology. Practical value. The proposed topology has proven to be extremely beneficial for implementing photovoltaic-based stand-alone multilevel inverter and electric vehicle charging applications. References 16, table 1, figures 18. E. Parimalasundar, R. Jayanthi, K. Suresh, R. Sindhuja. -
Investigation of electrical properties of developed indigenous natural ester liquid used as alternate to transformer insulation
The performance of every electrical system depends on the different electrical devices especially transformers. Petroleum-based mineral oil is widely used for insulation and cooling purpose. The disadvantage of mineral oil is its low biodegradability and is a major threat to the ecosystem due to its poor oxidative stability. To remedy the drawbacks, focus on alternative fluids that can replace traditional mineral oil. Alternative liquids such as natural esters are used which do not panic the ecosystem. With the support of additives in natural esters liquids, the productivity of the oil can be increased, paving the path for the green conversion of liquids in high voltage applications. The purpose of this article is to analyze the electrical properties of the newly developed indigenous oil. The inhibited oil was insulating oil to which antioxidants were added such as 2,6-ditertiary-butylparacresol, butylated hydroxyl anisole and tertiary butyl hydro qunine to slow down the oxidation rate and to check the electrical properties. This article discusses the electrical properties of mineral oil, developed indigenous oil with and without antioxidants as per IEC62770 standards. A 1.1 kVA transformer was then designed in a laboratory for load tests and Indigenous oil performance under load was evaluated. 2023 Institute of Advanced Engineering and Science. All rights reserved.