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Studies on K X Ray fluorescence parameters of low and medium Z elements
K X-ray fluorescence parameters for pure elements have been determined using different single and double reflection geometry by several researchers over the years. Horakeri et al.have shown that the K X-ray fluorescence parameters can also be determined by a simple 2and#960;-geometrical configuration method and a NaI(Tl) detector spectrometer for high Z elements. newlineHowever, in order to study the K XRF parameters for low Z elements, high resolution detector spectrometers are required.But in high resolution detectors like HPGe and Si(Li), due to the gap between window and the active area of the detector, the solid angle subtended by the detector at the target is not 2and#960;. Hence a suitable geometry correction is required for accurate newlinemeasurement of incident photons and the emitted K X-ray photons in order to determine the K XRF parameters in low Z elements. In the present study, employing a nearly 2and#960;-geometrical configuration and applying suitable geometry correction, we have determined the K X-ray fluorescence parameters of a few low and medium Z elements in the range of 27 and#8804; Z and#8804; 30 and 42 and#8804; Z and#8804; 47 respectively. The elements were procured in the form of thin foils and were irradiated by a weak radioactive source. The emitted K X-ray photons were detected using a low energy high resolution HPGe detector spectrometer. The incident photons, emitted K X-ray photons and the transmitted photons at newlinethe incident energy is measured and were corrected for window attenuation, efficiency, self-attenuation and geometry correction newlineto obtain the true intensities of incident photons, emitted K Xray photons and the transmitted photons at the incident energy. -
Studies on design and simulation of di-methyl ether plant of 160 TPD capacity
Energy is needed to run almost everything we see around us, from cars to the electricity power generation plants and everything else. Fossil fuels produce harmful products on combustion. One such eco-friendly alternative is Di-Methyl Ether also known as DME. In this study, a DME plant of capacity 160 tons per day was designed. Methanol dehydration process has been adapted as the process of production. The purity of DME from this plant is 99.5% by weight. Distillation column T-202 and heat exchanger E-208 were designed in detail. The detail design results showed that T-202 needed 6 stages for separation and a column diameter of 1.28m, while the simulation results showed 7 stages and column diameter as 1.285m for the same separation process. Furthermore, E-208 is of type 1-2 shell & tube heat exchanger with 307 tubes and tube length of 5.5m, however the Aspen EDR simulation results were also in close agreement with 304 tubes and 5m length for the same heat exchanger. This paper presents the results of simulation results of the simulation of these equipment's and full plant done using Aspen plus V8.8 software and Aspen EDR. 2023 Author(s). -
Studies on dark matter dark energy and possible alternate models
The nature of dark matter (DM) and dark energy (DE) which is supposed to constitute about 95% of the energy density of the universe is still a mystery. There is no shortage of ideas regarding the nature of both. While some candidates for DM are clearly ruled out, there is still a plethora of viable particles that fit the bill. In the context of DE, while current observations favour a cosmological constant picture, there are other competing models which may be equally likely. The standard model for the formation of structure assumes that there newlineexisted small fluctuations in the early universe that grew due to gravitational instability. The origin of these fluctuations are still unclear. In this study, we proposed the role of dark matter in providing the seed for star formation in the early universe, which is supported by very recent observations. With this we set observable constraints on luminosities, temperatures, and lifetimes of the early stars with an admixture of dark matter. We also studied the effects of the background repulsive dark energy density for large scale cosmic structures. The relation, and#119872;and#8260;and#119877;2 and#8776; 1and#119892;/and#119888;and#119898;2, seems to hold true for primeval galaxies as well as those at present epoch. From this, we set constraints on the nature and evolution of dark energy. Besides, we also set constraints on the size of galaxy clusters and superclusters due to the repulsive cosmological dark energy. This could indicate as to why large scale cosmic structures much larger than and#8764;200 Mpc are not seen.This study also looked at the evolution of the concept of the cosmological constant from its inception a little over a hundred years ago when Einstein introduced the cosmological constant in his General Theory of Relativity newlinein order to obtain a static universe to conform to the philosophical view of newlinethe universe at that time to it possibly making up close to about 70% of the energy density of the universe. -
Studies on color energy and its variations in graphs
This thesis consists of studies on color energy and its variations in graphs. Apart from the exploration of color energy corresponding to various coloring schemes, the notion of P-energy as a generalization of color energy has been introduced. The computation of color energy and P-energy of graphs has been carried out using Python programs, while the general results are derived using research methods and proof techniques in linear algebra. The bounds of color energy for a graph G have been established in terms of several graph parameters such as chromatic number and#967;(G), domination number and#947;(G), maximum degree and#8710;(G) etc. It has been found out that the color energy of a graph G is greater than or equal to 1 n and#947;(G) q 2(m + mand#8242;c). Further, the bounds of color energy of a graph G in terms of extreme eigenvalues of color matrix of G have been obtained. The study on color energy with respect to the minimum number of colors and L(h, k)-coloring has been examined in detail for some families of graphs such as star graph, double star, crown graph and their color complements. We have also examined the variation of color energy in the specific cases of T-coloring and radio coloring for some families of graphs. The examination of color energy corresponding to some improper colorings such as Hamiltonian coloring, open neighborhood coloring and improper C-coloring has also been done. Moreover, the color equi-energetic families of graphs with respect to various coloring schemes have been investigated. The concept of P-energy has been introduced as a generalization of the concept of color energy. This stems from the fact that coloring problems in essence are vertex partition problems. For any vertex partition P having k elements, we define the P-matrix AP(G) having and#8722;1, 0, 1, 2 as off diagonal entries and diagonal entries represent the cardinality of the elements in partition P. Then, the P-energy EP(G) is defined as the sum of the absolute values of eigenvalues of P-matrix of G. -
Studies on color energy and its variations in graphs
This thesis consists of studies on color energy and its variations in graphs. Apart from the exploration of color energy corresponding to various coloring schemes, the notion of P-energy as a generalization of color energy has been introduced. The computation of color energy and P-energy of graphs has been carried out using Python programs, while the general results are derived using research methods and proof techniques in linear algebra. The bounds of color energy for a graph G have been established in terms of several graph parameters such as chromatic number χ(G), domination number γ(G), maximum degree ∆(G) etc. It has been found out that the color energy of a graph G is greater than or equal to 1 n γ(G) p 2(m+m′ c ). Further, the bounds of color energy of a graph G in terms of extreme eigenvalues of color matrix of G have been obtained. -
Studies on anti-microbial potential of withania somnifera (l.) dunal and future perspectives: An overview
Withania somnifera is a herb of immense ethnopharmacological importance in Ayurvedic, Siddha and Unani systems of medicine. Due to its immense therapeutic potential and being an important source of novel withanolides, it has been a subject of immense intrigue among researchers. Apart from its anti-inflammatory, antitumor, anti-stress, antioxidant, immunomodulatory, antidiabetic, sedative and hemopoetic properties, there is mounting evidence for its antimicrobial and antiviral properties too. Various withanolides and steroidal lactones isolated so far are known to have high therapeutic value, but works pertaining to their antimicrobial potential have largely been at the synergistic level. No single withanolide has been characterized as a sole antimicrobial and thus, work in this regard is still in the stage of infancy, except for withanone which has recently shown in silico activity against SARS-COV-2. This review summarizes the elaborate antibacterial, antifungal, antiprotozoal and anti-viral work that has been done so far and casts focus on the limitations, in terms of mechanistic aspects of each. 2021 Society for Biology and Biotechnology. All rights reserved. -
Studies on air jet erosion behavior of plasma-sprayed Cr2C3 coatings on Al6061 alloy
This study assesses the efficacy of plasma-sprayed Cr2C3 coatings on AA6061 aluminum alloy in reducing erosion at different angles (30, 60, and 90). The experimental setup involved maintaining a distance of 80 mm between the components, feeding the powder at a rate of 55 g/min, and applying a current density of 460 amps. Weight loss measurements and surface morphology analyses were performed using scanning electron and confocal microscopy. The findings suggest that the Cr2C3 coating significantly improves erosion resistance when compared to specimens without any coating. The erosion angle had a significant impact on the performance of the coating. The coating experienced the least weight loss at an angle of 30 (28.45 g), followed by increased losses at angles of 60 (30.34 g) and 90 (34.2 g). These findings emphasize the significance of the impact angle in determining the severity of material removal. 2024 The Authors -
Studey of different types of modulations on double diffusive convection in lodroyd-b liquids
The problem aims to find the effects of temperature modulation in viscoelastic newlinefluids namely Oldroyd B liquids subjected to double diffusive convection. Both linear as well as a non-linear study has been carried out. A regular perturbation technique has been employed to determine the correction Rayleigh number. The results show that the Lewis number and strain retardation parameter induces stability to the system whereas stress relaxation parameter destabilizes the system for synchronous modulation. Truncated Fourier series represents the non-linear newlineanalysis. Mean Nusselt number and mean Sherwood number are used to quantify the newlineheat and mass transfer respectively. Strain retardation parameter and the Lewis number decrease the heat and mass transfer for synchronous modulation while stress relaxation parameter increases them. The opposite results are obtained for newlineasynchronous and lower wall modulations. Modulation is shown mostly to give rise newlineto super critical motion. -
Students Satisfaction with Remote Learning During the COVID-19 Pandemic: Insights for Policymakers
Purpose: This study aimed to learn more about the factors influencing student happiness and involvement in remote learning in Indian higher education institutions (HEIs). The study aims to assist administrators, strategists, and politicians in efficiently dealing with educations new normal. Methodology: The study used a quantitative research approach to fulfill the research aims. A sample of 546 students from various Indian HEIs was chosen, and data were gathered using standardized questionnaires. Structural equation modeling, confirmatory factor analysis, and importance-performance analysis (IPA) were used to calculate the student satisfaction index and examine the impact of various factors. Findings: The findings of this study revealed that institutional and faculty support emerged as the most influential factor impacting students satisfaction through remote learning. It also highlighted the need for HEIs to redesign the assessment process and evaluation techniques to adapt to the remote learning environment. Practical Implications: The findings of this study indicated the practical consequences for administrators, strategists, and policymakers at Indian HEIs. It was advised that improving institutional and teacher support should be a major concern in order to improve student happiness in remote learning situations. Furthermore, redesigning assessment procedures and evaluation processes may improve learning outcomes and student engagement. Originality: This study contributed to the existing body of knowledge by specifically investigating the factors influencing student satisfaction in remote learning within Indian HEIs. The findings shed light on the unique challenges and opportunities the shift to remote education presented. They offered valuable insights for managing and improving the quality of education during and beyond the pandemic. 2023, Associated Management Consultants Pvt. Ltd.. All rights reserved. -
Students Perception of Chat GPT
An artificial intelligence based Chatbot, ChatGPT was launched by Open AI in November 2022. In the field of education, ChatGPT has several benefits as well as challenges. Chat GPT can be considered as an advanced and a powerful tool to enhance the learning experience. It adds value to the education system only when it is used wisely. However, it is important to understand that the challenges must be addressed. It may act as a good source for collating the information, but it is always advised by the researchers that ones own perspective must be added to draw inferences from the output generated by ChatGPT. Our study supports the finding that ChatGPT can be used for the generation of ideas or to learn a new language. It also becomes imperative for the faculties to motivate students to use ChatGPT and add their inferences as well. AI models like ChatGPT can provide assistance, answer questions and provide explanations on various topics, making learning more accessible and tailored to individual needs. With this paper, we aim to provide a more informed discussion around the usage of ChatGPT in education. 2023 IEEE. -
Student's Performance Prediction Using Modified PSO
In the present-day education system, evaluating students' performance is very important. The prediction of student performance is helpful to students and instructors in maintaining a student's progress. Presently, institutions are implementing Continuous Evaluation Systems. This system is beneficial for improving the students' performance and helps increase their regularity in their studies. This work proposed a new version of the particle swarm optimization algorithm to classify students into different categories based on their performance with the help of various factors. The proposed model modified the strategy to increase the optimization algorithm's efficiency. This model deals with the bag of features with the modified optimization algorithm to recognize students' performance based on 33 features. These features are used for training, validation, and testing of the student's performance and generate a classification report which includes F-measure, recall, precision, and accuracy. Based on the classification report, the proposed model is compared with the existing methods, and the better performance of the proposed model is ascertained. 2023 IEEE. -
Student-Teacher Relationship Patterns in Undergraduate College
The student-teacher relationship has always been important at all levels of formal education, including undergraduate level. Positive student-teacher relationship plays direct role in facilitating students experience, and ultimately enhancing the academic outcomes. Furthermore, such relationship, especially at undergraduate level, becomes crucial since it also helps to facilitate the change and transformation process of adolescents who are stepping out from kindergraten-12th grade (K-12) system of education and venturing into college life. Given such importance and closeness in the relationship, this study attempted to examine the attachment patterns of the student-teacher relationship at undergraduate level. The research was guided by two broad questions. First, is student-teacher relationship at undergraduate level an attachment relationship? Second, if it is an attachment relationship, do distinct patterns exist? Drawing on two-dimensional internal working model of adult attachment postulated by Bartholomew (1980) as conceptual framework, the study explored the perception of 216 undergraduate students on student-teacher relationship from a university in Bangalore by using exploratory factor analysis (EFA). From the result two distinct dimensions, first related to students self and second associated to their view about availability of teachers and how they would reciprocate in the interactions, were observed which was later confirmed by CFA. The finding could help in future research to find the aspects of the relationship that promote the sense of security and supportiveness to enhance the academic outcomes of the students. Keywords: adult attachment patterns, student-teacher relationship -
Student-managed investment funds (SMIFs) in India: the perspectives of student fund managers
Purpose: This paper aims to explore how the student fund managers perceive the benefits of being part of the fund. Furthermore, this paper examines the country-specific challenges of setting up and managing a student-managed investment fund (SMIF) in India. Design/methodology/approach: Qualitative content analysis technique is used to identify, compare and retrieve critical themes about the present state of SMIF clubs in India. The data collection method involved structured, in-depth online interviews with ten student fund managers from various higher educational institutions in India. Findings: Some of the studys key findings indicate that the existence of SMIFs as part of learning facilitates group decision-making and peer learning. Additionally, this study brings to light specific issues related to registration, incorporating real-world practices and integrating SMIF into the academic curriculum. Social implications: The outcomes of this study shall be of use to students and the teaching fraternity across Indian colleges and universities who aspire to set up SMIFs as part of experiential learning. This study will also help existing SMIF clubs in India understand how their counterparts work and can consequently improvise their organizational structure and functioning. Originality/value: To the best of the authors knowledge, this is the first interview-based evaluation of the present structure of SMIFs structured as clubs in India. 2022, Emerald Publishing Limited. -
Student Subjective Wellbeing amidst the Covid-19 Pandemic in Iran: Role of Loneliness, Resilience and Parental Involvement
The COVID-19 pandemic and lockdowns potentially severely impact adolescents mental well-being. This research aims to study students subjective well-being during the covid-19 pandemic in Iran and investigate the role of loneliness, resilience, and parental involvement. For this study, 629 students (female = 345) were recruited by purposive sampling. Students were assessed on the Students Subjective Well-Being, Loneliness Scale, Resilience Scale, and Parental Involvement. The results confirm our hypothesis that the relationship between parental involvement and students subjective well-being is mediated by loneliness. Furthermore, the results indicated a partial mediation of resilience in the relationship between parental involvement and students subjective well-being. This study theoretically contributes to a better understanding of the factors determining the impact of traumatic events such as a pandemic on adolescents mental health. The implications of this study indicate interventions that can be carried out to minimize the negative psychological consequences of the pandemic. 2022, The Author(s), under exclusive licence to Springer Nature B.V. -
Student Perceptions and Experiences in Mathematics Classrooms: A Thematic Analysis
Classroom experiences contribute to learners' perceptions and interest in a particular subject. The present study aims to understand students' perception of mathematics learning by exploring their classroom experiences. The study sample consisted of 17 eighth-grade students in English-speaking urban schools in South India. The data was collected through a semi-structured interview schedule. The thematic analysis presents five themes student personal factors, teacher-related, content-related, classroom environment and utility value. Teachers characteristics and mathematics content were the essential factors contributing to students' perceptions and experiences. The study highlights the utility value of the content to help students see the application of the subject in real-world situations. Understanding students' perception of mathematics learning would help to choose appropriate content and teaching methods in the curriculum. The study highlights the need for educational and psychological interventions, focusing on student-teacher engagement and curriculum development to enhance mathematics learning. (2023). All Rights Reserved. -
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