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Study on gravitational waves from binary mergers and constraints on the Hubble parameter
Einsteins general theory of relativity predicted the existence of gravitational waves (GWs), which offer a way to explore cosmic events like binary mergers and could help resolve the Hubble Tension. The Hubble Tension refers to the discrepancy in the measurements of the Hubble Constant, Ho, obtained through different methods and missions over various periods. By analyzing gravitational wave data, particularly from mergers that also emit light (electromagnetic radiation), such as Bright Sirens, we aim to reduce this tension. This paper will investigate the properties of GWs produced by these binary mergers and utilize a mathematical framework to tackle the Hubble Tension. Future advancements in gravitational wave astronomy, particularly with initiatives like LIGO-India and LISA, promise to enhance research outcomes. The ground-based LIGO-India will increase sensitivity and improve localization, while the space-based LISA will target lower frequency ranges of GWs, enabling the detection of signals from a wider array of sources. Indian Association for the Cultivation of Science 2025. -
Study on heat transfer and pressure drop in tube-in-tube helical heat exchanger
The present work aims to investigate the effect of different configurations of the tube-in-tube helically coiled heat exchanger. Commercial CFD codes were used to predict the fluid flow and heat transfer in a tube-in-tube helical heat exchanger. The model of different configurations of the inner tube has been simulated by varying the Dean number. The numerical results are verified and found to be in good agreement with reported data in the literature. Nusselt Number and friction factor are evaluated for different angular positions. The use of geometry E increases the Nusselt number and friction factor by 19.05% and 16% respectively at a Dean number of 4000 as compared with a circular tube as compared with the circular tube. 2021 Tamkang University. All rights reserved. -
Study on Mechanical Properties of Lime Stabilized Active Bauxite Residue (Red Mud) and Fly Ash to Use as a Subgrade Material in Road Construction
Bauxite residue (Red mud) is a waste product produced during the extraction of aluminium from Bauxite by Bayers process. The huge requirement of aluminium for the various needs of mankind resulted to the enormous production of bauxite residue which is a very fine substance with high alkalinity. The high alkaline nature of this waste material shows a high impact on environment if it not covered or used in an appropriate method. This paper focusses on the usage of bauxite residue with the support of lime and flyash as a stabilizing material to use as a subgrade in road constructions and understand the toxicity levels of it upon leaching. Bauxite residue was stabilized with various ratios of fly ash and lime powder to its dry weight and determined the mechanical properties like California bearing ratio and unconfined compressive strength of all the combinations. Any industrial waste material will pose a environmental threat if the chemical analysis was not made upon using it as a subgrade material. In this study more emphasis was given to study the various hazardous chemicals present in the leachate collected from bauxite residue with fly ash and lime mixture. Leachate was collected by using Total characteristics leaching procedure (TCLP Method) and chemical analysis was performed and compared the results with the various water standards to recommend this material as a chemically safe material in the nature. All the results proved that bauxite residue upon stabilizing with the fly ash and lime is very much suitable to use as a subgrade material and environmentally safe. Kalahari Journals. -
Study on Photophysical Properties of N-Arylphthalamic Acid Derivative Containing 1, 2, 4-Triazole Scaffold
A novel N-arylphthalamic acid derivative, 2-({4-[(1H-1,2,4-triazol-1-yl)methyl]phenyl}carbamoyl)benzoic acid (TMPCB) was synthesized and their absorption and emission spectra were recorded in fifteen different solvents of varying polarities at room temperature. Ground state dipole moment of the derivative was calculated experimentally by Guggenheim method and solvatochromic approach proposed by Bilot-Kawski. The singlet excited state dipole moment of TMPCB were calculated experimentally based on different approaches of solvent polarity function proposed by LippertMataga, Bakhshiev, Kawskii-Chamma-Viallet, Reichardt and Bilot-Kawski. Singlet excited state dipole moment was greater than ground state dipole moment in all the approaches which could be attributed to considerable ?- electron density redistribution. Multiple Linear Regression (MLR) analysis based on Kamlet-Abboud-Taft and Catalan parameters were also studied to correlate solvatochromism and influence of solvents with absorbance and emission spectra. Ground and singlet excited state optimizations of the molecule were also performed using Gaussian 09W software. HOMO-LUMO energies of the phthalamic acid derivative have been obtained using TD-DFT/PCM (B3LYP/6-31G (d, p)) computations and experimentally by using cyclic voltammetry. Mulliken charges and molecular electrostatic potential plot have also been generated from DFT calculations to identify nucleophilic and electrophilic sites of TMPCB. 2017, Springer Science+Business Media, LLC. -
Study on radon concentration at the work places of Mysuru, Bengaluru and Kolar districts of Karnataka state, South India
Concentrations of radon, thoron and their progeny inside the working place depend on the activity of radionuclides in the soil, building materials, atmospheric conditions, construction of the building, type of work and ventilation condition. Radon is a radioactive noble gas, and it is emanated from 226Ra present in earth crest and building material. Based on the type of work, construction of the building and ventilation condition, concentrations of radon, thoron and their progeny have been measured in 60 workplaces at 10 locations of Mysuru, Bengaluru and Kolar districts of Karnataka state using Solid-State Nuclear Track Detector technique. From the study, variations of radon, thoron and their progeny have been observed with the nature of work. The Author 2016. Published by Oxford University Press. All rights reserved. -
Study on Space Debris Mitigation Under the National Space Laws
The international community is beginning to focus on the issue of space debris. Space debris has increased in the low Earth orbit due to accidental collisions between various space objects such as operational satellites. In China, the destruction of the FengYun - 1C weather satellite by an anti-satellite device caused an exponential increase in space debris. During the Ukraine war in 2022, Russia destroyed a defunct satellite which created space debris. This act put astronauts on the International Space Station at risk. Collisions have also happened between American satellites that are widely used for research or to provide communication facilities. Two unmanned European Space Agency (E.S.A.) satellites - the European Remote Sensing satellite (E.R.S.) and the Environmental Satellite (Envisat) - are currently in orbit reviving the debate over whether or not to engage in active debris removal. Despite gaining the interest of the international space community, efforts to reduce space debris have received scant legal recognition. Recent years have seen a dramatic decrease in launch costs, making space travel more affordable and feasible for the general public. As a result, smaller satellites can now be placed in low Earth orbit. Mega-constellations like SpaceX, OneWeb, Starlink, and Amazon Kuiper have also been launched or will be launched into space. It is predicted that about five per cent of all satellites will fail to be disposed of at the end of their lives, either because of technical difficulties or a lack of proper planning for the disposal phase. As a result, there is a greater possibility of collision with other celestial bodies. The problem of orbital pollution is made much worse by the fact that each collision can produce a large number of new pieces of debris. The inoperable satellites can only be retrieved from orbit with the active participation of the international community. The space sector is in the midst of a period of profound change. As a result of recent developments in microelectronics, materials, and battery technology, multiple constellations are now able to function in low Earth orbit, at altitudes of less than 1,000 kilometres. When it comes to domestic space regulation, the International Law Association (I.L.A.) Model marked a significant shift. As a result, many nations with space programmes have adopted national space laws that include provisions for dealing with space debris. Guidelines included in soft-law instruments have provided impetus in the absence of a mandatory international regime on space debris. 2024 University of Bologna. All rights reserved. -
Study on testing the stationarity and co-integration among the sectoral indices of national stock exchange of India
The Stock Market is a market for the trading of company stocks. It is an organized market place where members of the organization gather to trade company stocks and other securities. An index is important to measure the performance of investments against a relevant market index. Sectoral indices serve as a benchmark for measuring the performance of the stocks or portfolios. This study explores stationarity and co-integration relationship among stock market returns and the eight important NSE sectoral indices for the period of January 2013 to December 2017. Sectoral Index series indicates the existence of co integration among the sectoral indices of NSE. Co integration exists in long run equilibrium and in short run they diverge from each other or they have disequilibrium. This study is useful to find out the determinant factors of the National Stock Exchange and led lag relationship among the Sectoral Indices in National Stock Exchange. IAEME Publication. -
Study on the influence of modified chitosan on the preservation of tiger prawn penaeus monodon
Native chitosan, irradiated chitosan (5kGy and 10 kGy) and grafted chitosan was characterized and employed for the preservation of sea food Penaeus monodon. The grafting of metha acrylate onto natural native polymer chitosan was executed and the configuration and arrangement of covalent bonds in the grafted chitosan was demonstrated by performing, SEM, XRD, FTIR, TG and DSC analyses. The modified chitosan conferred antioxidant and antibacterial potential equivalent to or better than that of the unmodified chitosan in the stored Penaeus monodon. Modified chitosan treated Penaeus monodon produced less TBARS and TVB values than the control group. 2020 Slovak University of Agriculture. -
Study to assess attitudes towards statistics of business school students: An application of the SATS-36 in India
Students attitudes towards Statistics are pivotal to their learning process as positive attitudes lead to highly satisfactory course achievement and lead to positive outcomes outside class as well. In this paper we are exploring the perception of students of management apropos Statistics, familiarity with which is imperative in todays world of Analytics. The quantitative approach was used to compare attitudes of the students using the two versions of the SATS-36 instrument validated and copyrighted by Candace Schau. A Google form was used to collect responses and was sent to all the students who were enrolled in the Business Statistics course. 172 students responded for the pre-test study while 71 students responded for the post-test study. Data was analysed to see if gender, specialisation choices and previous math experiences accounted for differences in perceptions towards Statistics. It was found that students overall perception of statistics is positive and surprisingly they were more positive towards the beginning of the semester. These results are important as they can lead towards understanding of business students attitudes towards statistics and a way to refine the teaching learning process so that students are in a strong position to exploit the supply demand gap in the Analytics domain and deliver value to organisations. 2021 Eskisehir Osmangazi University. All rights reserved. -
Sub-type discernment of attention deficit hyperactive disorder in children using a cluster partitioning algorithm
Background/Objectives: Attention deficit hyperactive disorder is one major neuropsychiatric disorder particularly found in children. This medical disorder is difficult to identify and quantify, even if done, it is very subjective as it is the discretion of the psychiatrists or parents. Methods/Statistical analysis: The most exigent task after identifying ADHD children is to find their exact deficiency of what is the category, is it a hyperactive disorder, an impulsive disorder or an attention deficit disorder. Each category insists a diverse form of treatment and training. With the MRI image data the Tr values are estimated and given for clustering, a k-means algorithm was deployed for clustering. Findings: With different distance measures k-means was able to cluster precisely the three categories from the data. The result obtained would be a very substantial data for the medical physicists and an inevitable philanthropic contribution for the children society combating against this disorder. Applications/Improvements: The method adopted is novel and concise approach to identify the type of ADHD prevalent children. The method can be further perfected and completely automated to identify the category of ADHD in children. -
Subaltern languages : The question of vernaculars in 21st century India /
Jopurnal of Educational Planning And Administration, Vol.33, Issue 1, pp.51-65 -
Subaru Hyper Suprime-Cam Survey of Cygnus OB2 Complex - I. Introduction, photometry, and source catalogue
Low-mass star formation inside massive clusters is crucial to understand the effect of cluster environment on processes like circumstellar disc evolution, planet, and brown dwarf formation. The young massive association of Cygnus OB2, with a strong feedback from massive stars, is an ideal target to study the effect of extreme environmental conditions on its extensive low-mass population. We aim to perform deep multiwavelength studies to understand the role of stellar feedback on the IMF, brown dwarf fraction and circumstellar disc properties in the region. We introduce here, the deepest and widest optical photometry of 1. diameter region centred at Cygnus OB2 in r2, i2, z, and Y-filters, using Subaru Hyper Suprime-Cam (HSC). This work presents the data reduction, source catalogue generation, data quality checks, and preliminary results about the pre-main sequence sources. We obtain 713 529 sources in total, with detection down to ?28, 27, 25.5, and 24.5 mag in r2, i2, z, and Y-band, respectively, which is ?3 - 5 mag deeper than the existing Pan-STARRS and GTC/OSIRIS photometry. We confirm the presence of a distinct pre-main sequence branch by statistical field subtraction of the central 18 arcmin region. We find the median age of the region as ?5 2 Myr with an average disc fraction of ?9 per cent. At this age, combined with A $ 6 - 8 mag, we detect sources down to a mass range of ?0.01-0.17 M. The deep HSC catalogue will serve as the groundwork for further studies on this prominent active young cluster. 2021 The Author(s). -
Sublimation process and physical properties of vapor grown ?-In2Se3 platelet crystals
Indium selenide (?-In2Se3) crystals have been grown by the closed tube sublimation process in the absence of seed crystals and chemical transporting agents. The composition, structure and morphology of the samples grown under different vacuum conditions were examined by energy dispersive analysis, X-ray diffraction, and scanning electron microscope. Structural features of the crystals obtained in a vacuum of 10?3 mbar exhibited a few reflections not belonging to ? phase, whereas X-ray diffraction spectra of the crystals deposited under a vacuum of 10?6 mbar revealed evidence of sharp peaks with high intensities of ?-In2Se3 crystalline phase. When growth runs were performed for 72 h, voids were observed on the surface whereas for a duration of 120 h, platelet crystals were obtained. Optical properties of these samples were investigated using the FT-IR and photoluminescence spectroscopy. The average transmittance of the platelets in the visible and near infrared region of solar spectrum was found to be ?81% and an optical band gap of ?2.05 eV was computed from the transmission spectrum. Photoluminescence spectra of the grown In2Se3 crystals recorded at room temperature using an excitation laser of wavelength 355 nm showed a peak in the near band edge emission (NBE) corresponding to an energy of 2.01 eV. Under an illumination power of 12 mW/cm2, the photocurrent increased linearly with applied voltage and the dark current was found to be ~2.50?9 A for 10 V. These results suggest that the as-grown ?-In2Se3 platelets crystallized from vapor deposition, possess superior optoelectronic properties than the other phases for solar cell applications. 2016 Elsevier B.V. -
Subliminal Cueing in Visual Attention: Top-down and Bottom-up Processing
Exogenous subliminal cues have been shown to have both top-down and bottom-up effects. There are many research studies have confirmed that the effect of top-down variables dependent on cue characteristics. In response, other studies have attempted to exhibit purely stimulus-driven attention capture. The superiority of attention capture effects and the level of superiority in top-down cues have not been evidenced previously. The present study attempted to observe differential effects of cues with different levels of task relevancy, in both valid and invalid cues. As an addendum, conditions with valid cues and incorrect feature match allowed for the exploration of same-location costs in subliminal cues. The results indicated attentional capture effects of all valid cues irrespective of the level of task relevance in subliminal conditions. The cues with the highest task relevancy led to the most attention capture. There were no inhibitory effects of invalid cues on attention capture in subliminal cues. The study reiterates the possibility of attentional mechanisms in same-location costs implicating processing outside of memory. Further, facilitation and inhibition of attention capture in subliminal cues may have two independent mechanisms. The inhibitory mechanism may be contingent to conscious awareness of cues. The result of the study shows how attention can be exogenously oriented without conscious awareness and what kinds of cues might be most effective. These findings can be useful in educational and training settings and other settings where sustained attention is crucial. 2024, Iquz Galaxy Publisher. All rights reserved. -
Subspace graph topological space of graphs
A graph topology defined on a graph G is a collection T of subgraphs of G which satisfies the properties such as K0, G ? T and T is closed under arbitrary union and finite intersection. Let (X, T ) be a topological space and Y ? X then, TY = {U ? Y: U ? T } is a topological space called a subspace topology or relative topology defined by T on Y. In this P1 we discusses the subspace or the relative graph topology defined by the graph topology T on a subgraph H of G. We also study the properties of subspace graph topologies, open graphs, d-closed graphs and nbd-closed graphs of subspace graph topologies. 2023, Proyecciones. All Rights Reserved. -
Subspace spanning graph topological spaces of graphs
A collection of spanning subgraphs TS, of a graph G is said to be a spanning graph topology if it satisfies the three axioms: (Formula Presented) where, n = |V (G)|, the collection is closed under any union and finite intersection. Let (X, T ) be a topological space in point set topology and Y ? X then, TY = {U ? Y: U ? T } is a topological space called a subspace topology or relative topology defined by T on Y. In this paper we discusses the subspace spanning graph topology defined by the graph topology TS on a spanning subgraph H of G. 2023, Proyecciones. All Rights Reserved. -
Subsume Pediatric Headaches in Psychiatric Disorders? Critiques on Delphic Nosology, Diagnostic Conundrums, and Variability in the Interventions
Purpose of Review: Tension-type headache (TTH) continues to be the most prevalent type of headache across all age groups worldwide, and the global burden of migraine and TTH together account for 7% of all-cause years lived with disability (YLDs). TTH has been shown to have a prevalence of up to 80% in several studies and presents a wide range and high variability in clinical settings. The aim of this review is to identify gaps in diagnostics, nosology, and variability in the treatment of children and adolescents who present with headaches without an identifiable etiology. Recent Findings: Migraine and TTH have been debated to have more similarities than distinctions, increasing chances of misdiagnosis and leading to significant cases diagnosed as probable TTH or probable migraine. The lack of specificity and sensitivity for TTH classification often leads to the diagnosis being made by negating associated migraine symptoms. Although pathology is not well understood, some studies have suggested a neurological basis for TTH, in need of further validation. Some research indicates that nitric oxide signaling plays an integral part in the pain mechanisms related to TTH. Analgesics and non-steroidal anti-inflammatories are usually the first lines of treatment for children with recurring headaches, and additional treatment options include medication and behavioral therapies. Summary: With high prevalence and socioeconomic burden among children and adolescents, its essential to further study Tension-type headaches and secondary headaches without known cause and potential interventions. Treatment studies involving randomized controlled trials are also needed to test the efficacy of various treatments further. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Successful and Unsuccessful Revival Strategies of Indian Organisations - A Case Survey
European Journal of Business and Management Vol. 4, No. 15, pp. 142-147, ISSN No. 2222-2839 -
Successful turnarounds: the role of appropriate entrepreneurial strategies
Purpose The purpose of this paper is to report on a research study aimed at comparing the causes of organisational decline and turnaround strategies involved in cases of successful and unsuccessful turnarounds, with a view to identifying the differences, if any, between the two groups, which in turn is expected to provide useful information to academics, practitioners and policy makers. Design/methodology/approach Since turnaround is a business phenomenon of general interest, their stories are often published in business periodicals, which are a rich source of data on them. In order to tap this data source, the present paper employed a method of content analysis for the proposed investigation on the cause of organisational decline and turnaround strategies used. In order to quantify the data, a three-point scale was developed, where the presence of a cause/strategy is rated as 3, its ambivalence as 2 and its absence as 1, whose validity was assessed through the inter-rater agreement indices. The data thus generated are amenable to statistical analyses, using which the more commonly prevalent causes of organisational decline and the strategies commonly employed for turnaround by the successful and unsuccessful companies are identified. Findings The findings of the present study have generated a few useful insights. First, the primary causes for organisational decline are the internal weaknesses of the organisation; in fact the external changes can adversely affect the organisation only if it is internally weak. Second, organisational decline caused by multiple factors (which is usually the case) can be managed effectively by adopting a variety of strategies; hence a single-pronged strategy is often found to be ineffective. Third, the more successful turnarounds had a diverse portfolio of strategies including those of institution-building, often employed in a phased manner, consistent with the stage theories of turnaround. Research limitations/implications The limitations of this research arise mainly from the generation of data from published sources and the consequent biases, which can be managed, to a large extent, by using multiple sources for the same case for reducing the publishers biases as well as by having multiple raters for identifying the researchers biases, if any. Originality/value The study has highlighted the need for addressing the internal causes of organisational decline on a priority-basis rather than blaming the external factors, besides pointing to the need for adopting a variety of strategies for dealing with the diversity of causes affecting the organisations health, particularly the need for institutionalising the changes. These findings can be of help especially to turnaround managers and policy-makers in dealing with organisational decline and thus contribute to the creation and enhancement of economic value. 2015, Emerald Group Publishing Limited. -
Successful turnarounds: The role of appropriate entrepreneurial strategies /
Journal of Strategy and Management, Vol.8, Issue 1, ISSN No: 1755-425X.