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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. -
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. -
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 -
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. -
Radiation attenuation parameters and intrinsic efficiency of a few semiconductor crystals for radiation detection applications
This study investigates the effectiveness of nine inorganic semiconductor crystals ? LiGaSe2, LiInSe2, CsHgInS3, SnS, GaTe, BiI3, Sb2Te3, Tl4CdI6, and TlBr ? for radiation detection applications based on photon and charged particle (electrons, protons, and heavy ions) interaction parameters. Mass attenuation coefficient (?/?), half value layer (HVL), relaxation length (?), effective atomic number (Zeff), electron density (Neff), equivalent atomic number (Zeq), and exposure buildup factor (EBF) were computed using PAGEX software. These results, along with their intrinsic efficiencies calculated, were compared with that of standard materials (NaI(Tl), CdZnTe, and CdTe). The ?/? values of the studied semiconducting materials are ranked in the decreasing order as: TlBr, Tl4CdI6, BiI3, CsHgInS3, Sb2Te3, GaTe, SnS, LiInSe2, and LiGaSe2. TlBr, Tl4CdI6, BiI3, and Sb2Te3 show superior photon detection capabilities compared to the reference materials. TlBr and Tl4CdI6 have the highest intrinsic efficiency across nearly all energy regions, while LiGaSe2 has the lowest. Interaction parameters like range and Zeff for charged particles were also computed using standard databases, with SnS and Sb2Te3 showing the least range for all the charged particles studied throughout the entire energy region. The study indicates that TlBr and Tl4CdI6 have strong potential for developing next-generation radiation detectors with enhanced sensitivity, addressing needs in healthcare and national security. 2025 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). -
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 -
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 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 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 -
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. -
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. -
Radon transform based image steganography in frequency domain /
International journal Of Applied Engineering Research, Vol.10, Issue 70, pp.830-834, ISSN No: 0973-4562. -
Radon transform processed neural network for lung X-ray image based diagnosis
A novel method for image diagnosis with artificial learning is presented-ray images tuberculosis patients is subjected to neural network learning for prediction of diagnosis. The X-ray images of lungs are normally difficult for diagnosis, since its similarity to lung cancer. Under and over diagnosis of lung X-ray images is a difficult medical problem to resolve. In the present work radon transform of the x-ray images is fed to back propagation neural network trained with Levenberg algorithm. The present methodology gives sharp results, distincting the normal and abnormal images. 2014 IEEE. -
Railway Track Crack Detection: A Comparative Study On Yolov7 And U-Net In Automated Inspection
For railway networks to remain operationally safe and avoid catastrophic failures, structural integrity is essential. Track cracks can be found using labor-intensive, slow, and human error-prone manual inspection techniques. In this work, two cutting-edge deep learning models - YOLOv8 andU-Net v2 - for automated railway track crack detection using high-resolution imagery from Unmanned Aerial Vehicles (UAVs) are compared. In a real-world inspection scenario, we compare the different strategies of precise semantic segmentation (U-Net) and real-time object detection (YOLOv8) in order to assess their relative trade-offs. We compare performance on important metrics such as precision, recall, intersection over union (IoU), and inference speed using a custom dataset that was taken by a DJI Matrice 300 RTK drone. This work is novel because it examines how each model's output - bounding boxes versus pixel-level masks - directly affects the usefulness for maintenance workflows from an application-focused perspective. According to our research, U-Net v2 offers the fine-grained information required for precise damage assessment, while YOLOv8 is best suited for quick, extensive screening. This study offers railway operators useful information for creating a multi-stage, hybrid inspection strategy that strikes a balance between accuracy and speed. 2025 IEEE. -
Rain of Life, Rain of Music: Music as Life Power in Indian Thought and Contemporary Musical Traditions
Conceived as a life force, rain has a significant place in Indian thought. Sanskrit and vernacular literary and religious texts, as well as visual arts, emphasise its auspiciousness and importance in human life. Additionally, through the use of poetical images and metaphors, these texts and images associate rain with music and identify thunder with drums. Through the analysis of compositions from the repertoire of different drums such as the dhrupad pakh?vaj, the mi??vu of K?tiy???a? Sanskrit theatre, and the ritual music of Brahmanical temples of Kerala, this article studies the association of drumming with rain as a symbol of life force, consciousness and enlightenment. 2022 South Asian Studies Association of Australia. -
RAINBOW CHROMATIC TOPOLOGICAL INDICES OF CENTRAL GRAPHS OF SOME GRAPHS
The chromatic topological indices concept was introduced recently. Many other variations concerning the chromatic topological indices have been studied lately. In this paper, we have calculated the first and second rainbow chromatic Zagreb indices and rainbow chromatic irregularity indices for central graph of some standard graph classes. Palestine Polytechnic University-PPU 2024. -
Rainbow degree-jump coloring of graphs
In this paper, we introduce a new notion called the rainbow degree-jump coloring of a graph. For a vertex v ? V(G), let the degree-jump closed neighbourhood of this vertex be defined as Ndeg [v] = {u: d(v, u) ? d(v)}. A proper coloring of a graph G is said to be a rainbow degree-jump coloring of G if for all v in V(G), c(Ndeg [v]) contains at least one of each color class. We determine a necessary and sufficient condition for a graph G to permit a rainbow degree-jump coloring. We also determine the rainbow degree-jump chromatic number, denoted by ?rdj (G), for certain classes of cycle related graphs. Mphako-Banda E.G., Kok J., Naduvath S., 2021. -
Rainbow Dominator Coloring of Graphs
Coloring and domination in graphs are two well explored areas of research in graph theory. Blending these notions, the dominator coloring of graphs was introduced in the literature; following which several variants of domination related coloring patterns have been defined and studied, based on different types of coloring and domination in graphs. A vertex coloring of a graph that demands the existence of a path in which every internal vertex between two vertices has a unique color is called a rainbow vertex coloring of the graph. In this article, we investigate the rainbow dominator coloring of graphs; a vertex coloring that combines the concepts of rainbow vertex coloring and dominator coloring of graphs. We discuss some properties of the rainbow dominator coloring of graphs and determine the rainbow dominator chromatic number of certain classes of graphs and their complements. 2025, SINUS Association. All rights reserved. -
Rainbow Dominator Coloring of Some Cycle Related Graphs
The concept of dominator coloring of graphs emerged as a combination of the two prominent structural aspects of graphs, namely coloring and domination in graphs. The vertex coloring that demands the existence of a rainbow path between any two vertices of a graph; that is, a path in which every internal vertex has a unique color, is called a rainbow vertex coloring of a graph. Melding the concepts of rainbow vertex coloring and dominator coloring of graphs, the rainbow dominator coloring of graphs has been studied, in the literature. In this article, we investigate the rainbow dominator coloring of some cycle related graphs, and their complements. 2025, SINUS Association. All rights reserved.