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RADON in GROUNDWATER of MAGADI TALUK, RAMANAGARA DISTRICT in KARNATAKA
Radon is a water-soluble radioactive noble gas produced from the alpha decay of 226Ra in uranium series. Its presence in drinking water and open air increases the risk of lung and intestinal cancers in human beings. In view of this, radon concentration in groundwater and its dose due to inhalation and ingestion to the population of Magadi taluk of Ramanagara district in Karnataka state, India was studied. The groundwater samples were analyzed for radon concentration using emanometry technique. The study showed that the radon concentration in this area varied from 27.4 1.0 to 167.5 3.9 Bq/L and the effective dose ranged from 104.2 2.7 to 636.2 11.0 ?Sv/a. The study also revealed that 95% of the 37 samples studied showed higher radon concentration compared to the UNSCEAR recommendation (40 Bq/L) and all the samples showed higher than the USEPA recommendation (11.1 Bq/L). Ten samples have concentration above the maximum permissible level prescribed by WHO (100 Bq/L). The groundwater samples are found to be slightly alkaline within the permissible limit of Indian Standards. 2018 The Author(s). Published by Oxford University Press. All rights reserved. -
Radio pulsar sub-populations (II): The mysterious RRATs
Several conjectures have been put forward to explain rotating radio transients (RRATs), the newest subclass of neutron stars, and their connections to other radio pulsars. This work discusses these conjectures in the context of the characteristic properties of the RRAT population. Contrary to expectations, it is seen that: (a) the RRAT population is statistically un-correlated with the nulling pulsars and (b) the RRAT phenomenon is unlikely to be related to old age or death-line proximity. It is perhaps more likely that the special emission property of RRATs is a signature of them being later evolutionary phases of other types of neutron stars which may have resulted in restructuring their magnetic fields. 2022, Indian Academy of Sciences. -
Radiative nonlinear 3D flow of ferrofluid with Joule heating, convective condition and Coriolis force
Characteristics of heat transport mechanism in three-dimensional ferrofluid flow past a deformed surface subjected to the Coriolis and Lorentz forces are analyzed. The impacts of Joule heating, nonlinear thermal radiation, viscous dissipation and convective condition are also accounted. The carrier fluid (water) is embedded by Fe3O4 nanoparticles. The boundary layer approximations are employed in problem statement. Stretching transformations are utilized to form nonlinear ODE system from governed PDE system. The subsequent system is treated numerically via Runge-Kutta-Fehlberg method. Effects of relevant parameters on different flow fields are discussed comprehensively with help of graphs. It is established that the heat transfer rate is enhanced due to Coriolis and Lorentz forces. Furthermore, Fe3O4 nanoparticles enhance the Nusselt number significantly in comparison with Al2O3 nanoparticles. 2017 -
Radiative heat transport and unsteady flow in an irregular channel with aggregation kinematics of nanofluid
In this study, an unsteady free convective heat transfer and the laminar flowof incompressible nanoliquid in a wavy channel subjected to the nanoparticles aggregation effects were studied. For the investigation, ethylene glycol-based nanofluid with titania nanoparticles was used. Here, the role of the nanoparticle aggregation, thermal radiation, applied magnetic field, and internal heat absorption is examined. A semi-analytical solution of the complicated partial differential equation is obtained by the method of regular perturbation. The effect of several parameters on velocity and temperature profile has been studied. In addition, Nusselt number (Nu) and skin friction (Formula presented.) are also examined and analyzed with the help of graphs. It has been observed that the velocity profile enhances with aggregation effect than without aggregation effect. The aggregation effects are minimal for smaller volume fraction of nanoparticles. A reverse trend near the wavy wall is visible for all parameters. The magnitude of velocity decreased as an effect of the applied magnetic field, whilethe magnitude of velocity increased due to radiative heat flux. Furthermore, the heat sink mechanism reduces the magnitude of the nanofluid temperature. 2021 Wiley Periodicals LLC -
Radiative heat transfers of Carreau fluid flow over a stretching sheet with fluid particle suspension and temperature jump
The current study is to deliberate the flow and heat transfer of a Carreau fluid over a stretching sheet with fluid particle suspension. The temperature jump is also taken into account. The standard nonlinear system is resolved numerically via Runge-Kutta based shooting scheme. Role of substantial parameters on flow fields as well as on the fiction factor and heat transportation rates are determined and conferred in depth through graphs. It's found that the velocity profile decreases and temperature profile increases, with an increasing the values of Weissenberg parameter. Further, the higher thermal slip parameter reduces the thermal boundary layer thickness. The thermal boundary layer thickness of fluid and dust particles decreases with the rise in Prandtl number. 2017 The Authors -
Radiative heat transfer of nanomaterial on a convectively heated circular tube with activation energy and nanoparticle aggregation kinematic effects
The improvement of the thermal conductivity of the nanoliquid due to the inclusion of a certain amount of nanoparticles is well known. However, the cause of the observed abnormal improvement remains unclear. For this reason, the aggregation kinematics of nanoparticles is significant for evaluating the appropriate thermal effect of particles at the nanoscale. The scope of nanomaterials can be seen in various engineering and industrial fields such as nuclear reactor coolants, heat exchangers, aircraft coolants, microreactor coolants, automobile radiators, solar collectors, etc. Therefore, this study investigates the effects of the aggregation of nanoparticles on radiative nanoliquid flow with activation energy over a horizontal tube subjected to the convective thermal boundary conditions. Experimentally verified correlations of multiwall carbon nanotube aggregation are utilized. The response surface methodology (RSM) is used to determine the optimum levels of the physical parameters to maximize the mass transfer rate of the nanoliquid. The magnitude of the volume fraction and velocity are superior in the absence of aggregation kinematics than in the presence of nanoparticles aggregation mechanism. From the RSM analysis, the maximum Sherwood number obtained is 1.1384 with desirability d = 0.9993. The present results may have applications in nanoliquid-dependent structures, heating/cooling processes, and thermal systems. 2021 Elsevier Ltd -
Radiation effects on 3D rotating flow of Cu-water nanoliquid with viscous heating and prescribed heat flux using modified Buongiorno model
In this article, the three-dimensional (3D) flow and heat transport of viscous dissipating Cu-H2O nanoliquid over an elongated plate in a rotating frame of reference is studied by considering the modified Buongiorno model. The mechanisms of haphazard motion and thermo-migration of nanoparticles along with effective nanoliquid properties are comprised in the modified Buongiorno model (MBM). The Rosseland radiative heat flux and prescribed heat flux at the boundary are accounted. The governing nonlinear problem subjected to Prandtls boundary layer approximation is solved numerically. The consequence of dimensionless parameters on the velocities, temperature, and nanoparticles volume fraction profiles is analyzed via graphical representations. The temperature of the base liquid is improved significantly owing to the existence of copper nanoparticles in it. The phenomenon of rotation improves the structure of the thermal boundary layer, while, the momentum layer thickness gets reduced. The thermal layer structure gets enhanced due to the Brownian movement and thermo-migration of nanoparticles. Moreover, it is shown that temperature enhances owing to the presence of thermal radiation. In addition, it is revealed that the haphazard motion of nanoparticles decays the nanoparticle volume fraction layer thickness. Also, the skin friction coefficients found to have a similar trend for larger values of rotation parameter. Furthermore, the results of the single-phase nanoliquid model are limiting the case of this study. 2021, The Author(s). -
Radiated flow of chemically reacting nanoliquid with an induced magnetic field across a permeable vertical plate /
Results In Physics, Vol.7, pp.2375-2383, ISSN: 2211-3797. -
Radiated flow of chemically reacting nanoliquid with an induced magnetic field across a permeable vertical plate
Impact of induced magnetic field over a flat porous plate by utilizing incompressible water-copper nanoliquid is examined analytically. Flow is supposed to be laminar, steady and two-dimensional. The plate is subjected to a regular free stream velocity as well as suction velocity. Flow formulation is developed by considering MaxwellGarnetts (MG) and Brinkman models of nanoliquid. Impacts of thermal radiation, viscous dissipation, temperature dependent heat source/sink and first order chemical reaction are also retained. The subjected non-linear problems are non-dimensionalized and analytic solutions are presented via series expansion method. The graphs are plotted to analyze the influence of pertinent parameters on flow, magnetism, heat and mass transfer fields as well as friction factor, current density, Nusselt and Sherwood numbers. It is found that friction factor at the plate is more for larger magnetic Prandtl number. Also the rate of heat transfer decayed with increasing nanoparticles volume fraction and the strength of magnetism. 2017 The Authors -
Radha-Kishangarh
In 1778 the great exponent of the art of miniature painting, Nihal Chand, created the legendary face of the Kishangarh Radha, the quintessence of Indian womanhood and grace. -
Radar Cross Section (RCS) of HIS-based Microstrip Patch Array: Parametric Analysis
Low profile structures such as High Impedance Surfaces (HIS) are capable of modifying the scattering properties of a radiating structure. This paper presents the novel design of patch antenna/array with non-uniform HIS based ground plane. Two FSS elements of different dimensions are designed with different resonant frequencies. The performance of the high impedance surfaces has been carried out by varying the HIS dimensions and height of the substrate. Using the analyses, patch antenna/array with ground plane based on non-uniform configurations of HIS elements are designed. The radiation and scattering characteristics of microstrip patch antenna/array with HIS- based ground plane are compared to those with conventional PEC-based ground plane. A maximum of 8 dB RCS reduction has been achieved for patch array with non-uniform HIS layer. 2018 IEEE. -
Rabindranath Tagore 1861-1941
The Indian Postal Department released the first stamp on Tagore in 1952, as part of a set of six stamps on leading poets and saints of India, Kabir, Tulsidas, Meera, Surdas, Mirza Ghalib and Rabindranath Tagore. These stamps were the first to be printed, using the photogravure technology in place of the lithographic one. -
Qutrit-Inspired Fully Self-Supervised Shallow Quantum Learning Network for Brain Tumor Segmentation
Classical self-supervised networks suffer from convergence problems and reduced segmentation accuracy due to forceful termination. Qubits or bilevel quantum bits often describe quantum neural network models. In this article, a novel self-supervised shallow learning network model exploiting the sophisticated three-level qutrit-inspired quantum information system, referred to as quantum fully self-supervised neural network (QFS-Net), is presented for automated segmentation of brain magnetic resonance (MR) images. The QFS-Net model comprises a trinity of a layered structure of qutrits interconnected through parametric Hadamard gates using an eight-connected second-order neighborhood-based topology. The nonlinear transformation of the qutrit states allows the underlying quantum neural network model to encode the quantum states, thereby enabling a faster self-organized counterpropagation of these states between the layers without supervision. The suggested QFS-Net model is tailored and extensively validated on the Cancer Imaging Archive (TCIA) dataset collected from the Nature repository. The experimental results are also compared with state-of-the-art supervised (U-Net and URes-Net architectures) and the self-supervised QIS-Net model and its classical counterpart. Results shed promising segmented outcomes in detecting tumors in terms of dice similarity and accuracy with minimum human intervention and computational resources. The proposed QFS-Net is also investigated on natural gray-scale images from the Berkeley segmentation dataset and yields promising outcomes in segmentation, thereby demonstrating the robustness of the QFS-Net model. 2012 IEEE. -
Question-answering versus machine reading comprehension: Neural machine reading comprehension using transformer models
Teaching machines to read and learn natural language documents and seek answers to questions is an elusive task. Traditional question-answering systems were based on rule-based and keyword-searching algorithms without proper natural language understanding. Machine reading comprehension (MRC) belongs to reading comprehension models and facilitates the machines learning from context. MRC can infer the answer from the context through language understanding. Neural machine reading comprehension has built reading comprehension models by employing the advancements of deep neural networks that have shown unprecedented performance compared to other non-neural and feature-based models. The article comprises the MRC span extraction tasks using Transformer models and, in addition, the illustration of the MRC tasks, trends, modules, benchmarked datasets, implementation, and empirical results. 2024 selection and editorial matter, Muskan Garg, Sandeep Kumar and Abdul Khader Jilani Saudagar chapters. -
Queering Doctor Who and Supernatural: An ecofeminist response to Bill Potts and Charlie Bradbury
Both Bill Potts from Doctor Who and Charlie Bradbury from Supernatural are iconic lesbian characters who have irreversibly changed the landscape of the long-running shows in which they are featured: the first queer character to appear on Doctor Who as a companion since Captain Jack Harkness, Bill Potts, is the shows first lesbian character to feature in a starring role. Her story arc is bookended by her relationship with Heather, who is first encountered in Bills first episode on the series and who returns to save Bills life at the end of her time as the Doctors companion. Heathers association with what appears to be water or oil-but is eventually revealed to be an alien life force resembling a liquid-is a significant factor in her transition from human to trans-human, and the elemental force that she becomes may be related to the transcendentalist roots of ecocritical discourse. Similarly, Charlie Bradburys role as the Queen of Moondor, a Live Action Role Playing arena, and her subsequent encounter with the faerie Gilda may be viewed in the context of the correlation of geek culture and the return to the natural, pre-industrial/pre-technological world of the episode LARP and the Real Girl (2013). These analyses are examined through an ecofeminist lens that consists primarily of approaches to ecofeminism in the twenty-first century. As Greta Gaard observes in her 2011 essay Ecofeminism Revisited: Rejecting Essentialism and Re-Placing Species in a Material Feminist Environmentalism, " ecofeminism in the late twentieth century declined because of charges of gender essentialism. However, given the emergence of areas such as animal studies, vegan studies, and speciesism, ecocriticism has again risen to prominence in the field of gender studies, and perhaps one way of avoiding the charge of essentialism is to place ecofeminist criticism within the larger framework of questions relating to a pluralistic and queer sense of gender and sexual identities. In this, both Bill and Charlie lend themselves to interpretations based on emerging discourses in ecocritical queer studies. 2021 selection and editorial matter, Douglas A. Vakoch. -
Quasar catalogue for the astrometric calibration of the forthcoming ILMT survey
Quasars are ideal targets to use for astrometric calibration of large scale astronomical surveys as they have negligible proper motion and parallax.The forthcoming 4-m International Liquid Mirror Telescope (ILMT) will survey the sky that covers a width of about 27?. To carry out astrometric calibration of the ILMT observations, we aimed to compile a list of quasars with accurate equatorial coordinates and falling in the ILMT stripe. Towards this, we cross-correlated all the quasars that are known till the present date with the sources in the Gaia-DR2 catalogue, as the Gaia-DR2 sources have position uncertainties as small as a few milli arcsec (mas). We present here the results of this cross-correlation which is a catalogue of 6738 quasars that is suitable for astrometric calibration of the ILMT fields. In this work, we present this quasar catalogue. This catalogue of quasars can also be used to study quasar variability over diverse time scales when the ILMT starts its observations. While preparing this catalogue, we also confirmed that quasars in the ILMT stripe have proper motion and parallax lesser than 20 masyr- 1 and 10 mas, respectively. 2020, Indian Academy of Sciences. -
Quartic autocatalysis of homogeneous and heterogeneous reactions in the bioconvective flow of radiating micropolar nanofluid between parallel plates
This study deals with the quartic autocatalysis of homogeneousheterogeneous chemical reaction that occurs in the bioconvective flow of micropolar nanofluid between two horizontally parallel plates. The quartic autocatalysis is found to be more effective than cubic autocatalysis since the concentration of the homogeneous species is substantially high. The upper plate is assumed to be in motion and the lower plate is kept stationary. Such a flow of micropolar fluid finds application in the pharmaceutical industry, microbial enhanced oil recovery, hydrodynamical machines, chemical processing,and so forth. The governing equations for this flow are in the form of the partial differential equation and their corresponding similarity transformation is obtained through Lie group analysis. The governing equations are further transformed to coupled nonlinear differential equations that are linearized through the Successive linearization method and are solved using the Chebyshev Collocation method. The effects of various parameters, such as micropolar coupling parameter, spin gradient parameter, reaction rates, and so forth, are analyzed. It is observed that the fluid flows with a greater velocity away from the channel walls, whereasnear the channel walls the velocity decreases with an increase in the coupling parameter. Furthermore, the spin parameter increases the spin gradient viscosity that reduces the microrotation of particles that further decreases the microrotation profile. 2021 Wiley Periodicals LLC -
Quarantined effects and strategies of college students COVID-19
Purpose: The world is battling with one of the biggest health crisis caused by novel COVID-19. This paper aims to understand the effect of quarantine on the psychological health of college students and the coping strategies adopted by them. Design/methodology/approach: The study adopted the interview method and focused on two crucial open-ended questions: how quarantine has impacted and what are the strategies adopted to overcome the same. The response was recorded through email and phone from a sample of 30 students. Findings: Most of the students stated that they are going through issues like anxiety, depression, infection fear, ambiguity due to this pandemic and the lockdown related to it. However, they engage themselves with various activities that help them to combat this situation. Practical implications: Education institutions can focus on conducting online fest and other events to engage students more productively. They can also focus on developing a wellness application to support these students. They can provide solutions and tips to balance mental health and wellness during these times. Originality/value: Everyone knows about COVID-19 and the measures taken related to it, but not much about the impact of it on mental health. This paper discusses the negative impact of quarantine on students and coping strategies adopted by them. The strategies mentioned in the study can guide quarantined people, student community, parents, counsellors and academic facilitators to handle the situation in a better way. 2020, Emerald Publishing Limited. -
Quantum-inspired meta-heuristic approaches for a constrained portfolio optimization problem
Portfolio optimization has long been a challenging proposition and a widely studied topic in finance and management. It involves selecting and allocating the right assets according to the desired objectives. It has been found that this nonlinear constraint problem cannot be effectively solved using a traditional approach. This paper covers and compares quantum-inspired versions of four popular evolutionary techniques with three benchmark datasets. Genetic algorithm, differential evolution, particle swarm optimization, ant colony optimization, and their quantum-inspired incarnations are implemented, and the results are compared. Experiments have been carried out with more than 10 years of stock price data from NASDAQ, BSE, and Dow Jones. This work proposes several enhancements to allocate funds efficiently, such as improved crossover techniques and dynamic and adaptive selection of parameters. Furthermore, it is observed that the quantum-inspired techniques outperform the classical counterparts. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024. -
Quantum vs. Classical: A Rigorous Comparative Study on Neural Networks for Advanced Satellite Image Classification
Navigating the intersection of quantum computing and classical machine learning in image classification, this study confronts prevailing challenges. Centered on the "Satellite Image dataset (RSI-CB256),"our investigation probes the early phases of quantum architectures, utilizing simulations to transform numerical data into a quantum format, the investigation highlights the existing limitations in traditional classical methodologies for image classification tasks. In light of the groundbreaking possibilities presented by quantum computing, this study underscores the need for creative solutions to push image classification beyond the usual methods. Additionally, the study extends beyond conventional CNNs, incorporating Quantum Machine Learning through the Qiskit framework. This dualparadigm approach not only underscores the limitations of current classical machine learning methods but also sets the stage for a more profound understanding of the challenges that quantum methodologies aim to address. The research offers valuable insights into the ongoing evolution of quantum architectures and their potential impact on the future landscape of image classification and machine learning. 2024 IEEE.