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Numerical simulation of self-similar thermal convection from a spinning cone in anisotropic porous medium

Journal of Hydrodynamics 2016年第2期28卷 184-194页

作者： O. Anwar BEG m. J. UDDIN T. BEG R. reddy GORLA Spray Research Group Petroleum and Gas Engineering Division Room G77 Newton Building School of Computing Science and Engineering (CSE) University of Salford M54WT UK Department of mathematics American International University-Bangladesh Dhaka Bangladesh Engineering mechanics Associates Dickenson Road Manchester M 16 England UK Department mechanical Engineering Cleveland State University Cleveland Ohio USA

Self-similar steady natural convection thermal boundary layer flow from a rotating vertical cone to anisotropic Darcian porous medium is investigated theoretically and numerically. The transformed non-dimensional two-point boundary value problem is reduced to a system of coupled, highly nonlinear ordinary differential equations, which are solved subject to robust surface and free stream boundary conditions with the mAPLE 17 numerical quadrature software. Validation with earlier non-rotating studies is included, and also further verification of rotating solutions is achieved with a variational finite element method （FEm）. The rotational （spin） parameter emerges as an inverse function of the Grashof number. The influence of this parameter, primary Darey number, secondary Darcy number and Prandtl number on tangential velocity and swirl velocity, temperature and heat transfer rate are studied in detail. It is found that the dimensionless tangential velocity increases whilst the dimensionless swirl velocity and temperature decrease with the swirl Darcy number, tangential Darcy number and the rotational parameters. The model finds applications in chemical engineering filtration processing, liquid coating and spinning cone distillation columns.

关键词： self-similarity spinning cone finite element method (FEm) anisotropic porous medium heat transfer mAPLE FEm

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Numerical modeling of friction stir welding using the tools with polygonal pins

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Defence Technology（防务技术） 2015年第3期11卷 229-236页

作者： m. mEHTA G.m. reddy A.V. RAO A. DE Production Engineering Department BVM Engineering College Defense metallurgical Research Laboratory mechanical Engineering Department

Friction stir welding using the tools with polygonal pins is often found to improve the mechanical strength of weld joint in comparison to the tools with circular pins. However, the impacts of pin profile on the peak temperature, tool torque and traverse force, and the resultant mechanical stresses experienced by the tool have been rarely reported in a systematic manner. An estimation of the rate of heat generation for the tools with polygonal pins is challenging due to their non-axisymmetric cross-section about the tool axis. A novel methodology is presented to analytically estimate the rate of heat generation for the tools with polygonal pins. A three-dimensional heat transfer analysis of friction stir welding is carried out using finite element method. The computed temperature field from the heat transfer model is used to estimate the torque, traverse force and the mechanical stresses experienced by regular triangular, square, pentagon and hexagon pins following the principles of solid mechanics. The computed results show that the peak temperature experienced by the tool pin increases with the number of pin sides. However, the resultant maximum shear stress experienced by the pin reduces from the triangular to hexagonal pins.

关键词：搅拌摩擦焊接多边形管脚数值模拟摩擦搅拌焊接机械强度峰值温度机械应力

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Perturbations in Earth's Atmosphere over An Indian Region during the Total Solar Eclipse on 22 July 2009

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Journal of meteorological Research 2019年第4期33卷 784-796页

作者： S.B.Surendra PRASAD Vinay KUmAR K.Krishna reddy S.K.DHAKA Shristy mALIK m.Venkatarami reddy U.murali KRISHNA Semi-arid-zone Atmospheric Research Centre SARC Department of Physics Yogi Vemana University Radio and Atmospheric Physics Lab Rajdhani College University of Delhi Department of Applied Physics Delhi Technical University

During a total solar eclipse(TSE) on 22 July 2009, atmospheric perturbations were monitored from the surface to thermosphere to understand TSE’s impact on the meteorological(temperature, relative humidity, wind speed, and wind direction) and chemical(O3and NOx) parameters around Kadapa(14.28°N, 78.42°E), a tropical semi-arid region of India. For this purpose, an experiment was conducted at Yogi Vemana University Campus, Kadapa, India, to measure the temperature, wind speed, wind direction, and concentrations of ozone(O3), NO, NO2, and NOxby using the automatic weather station(AWS) and O3analyzer. On the eclipse day(22 July 2009), the surface observations at Kadapa showed a reduction in temperature(about 1.1°C) because of the solar insulation. Comparison of the thermal,dynamical(wind), and chemical parameters on the TSE day with control days [preceding(21 July 2009) and succeeding(23 July 2009) the TSE] illustrated the influence of solar eclipse. During the eclipse period, the O3mixing ratio decreased, while NO2and NOxincreased; however, NO remained unchanged. In addition, radio occultation(RO)temperature profiles from Constellation Observing System for meteorology, Ionosphere, and Climate(COSmIC)/Formosat Satellite mission(FORmOSAT-3) and Thermosphere, Ionosphere, and mesosphere Energetics and Dynamics(TImED) satellites were utilized to understand the impact of TSE on dynamics of the middle and upper atmosphere from tropopause to the thermosphere. High vertical resolution COSmIC observations revealed that during the solar eclipse, tropopause was cooler with twin peaks(double tropopause). The lower thermosphere between 110 and 130 km became warmer during the TSE, which might be caused by the dynamical response of the atmosphere in this region to the solar eclipse. The experimental data have provided very fine-scale variations of the atmospheric parameters both in time and height and also constituted a new set of results on TSE for further research.

关键词： total solar eclipse(TSE) atmospheric perturbations tropopause dynamics COSmIC/FORmOSAT-3 satellite radio occultation(RO) observations

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For antigen-specific effector or Foxp3^(+) regulatory T cell fate, cyclin-dependent kinases hold the trump card

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Cellular & molecular Immunology 2020年第4期17卷 310-312页

作者： Srinivasa reddy Bonam Jagadeesh Bayry Neuroimmunology&peptide therapy Biotechnology and cell signalingCNRS-University of StrasbourgIllkirch 67412 StrasbourgFrance Institut National de la Santéet de la Recherche médicale Centre de Recherche des CordeliersEquipe-Immunopathologie et Immunointervention ThérapeutiqueSorbonne UniversitéUniversitéParis DescartesSorbonne Paris CitéParis F-75006France

Forkhead box p3^(+)(Foxp3^(+))regulatory T cells(Tregs)are indispensable for immune homeostasis and for maintaining immune *** studies have confirmed that injection of a T cell population depleted of Tregs causes autoimmunity,rejection of grafts and inflammatory disorders,whereas reconstitution with Tregs inhibits these pathogenic *** the last two decades,intense efforts have been made to identify Treg subsets,Treg differentiation processes,and the molecular signatures and regulators that determine Treg lineage specificity and stability.1–6 Several lines of evidence clearly demonstrate that Foxp3^(+)Tregs do not constitute a homogeneous population,and various subsets of Tregs,such as thymic Tregs(tTregs),in vitro-generated Tregs(iTregs),and peripherally induced Tregs(pTregs),have been identified.5 In addition to Foxp3,epigenetic factors and metabolic processes play key roles in maintaining Treg identity and function,and mediate the switch between effector T cells and Tregs.

关键词： Foxp3 specificity homeostasis

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modified distance regularized level set evolution for brain ventricles segmentation

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Visual Computing for Industry,Biomedicine,and Art 2020年第1期3卷 329-340页

作者： Thirumagal Jayaraman Sravan reddy m manjunatha mahadevappa Anup Sadhu Pranab Kumar Dutta School of medical Science and Technology IIT KharagpurKharagpur 721302India Department of Electronics and Communications JNTUA-College of EngineeringPulivendula 516390India EKO CT&mRI Scan Centre Medical CollegeCalcutta 700073India Department of Electrical Engineering IIT KharagpurKharagpur 721302India

Neurodegenerative disorders are commonly characterized by atrophy of the brain which is caused by neuronal *** are one of the prominent structures in the brain;their shape changes,due to their content,the cerebrospinal *** the morphological changes of ventricles,aids in the diagnosis of atrophy,for which the region of interest needs to be separated from the *** study presents a modified distance regularized level set evolution segmentation method,incorporating regional intensity *** proposed method is implemented for segmenting ventricles from brain images for normal and atrophy subjects of magnetic resonance imaging and computed tomography *** of the proposed method were compared with ground truth images and produced sensitivity in the range of 65%–90%,specificity in the range of 98%–99%,and accuracy in the range of 95%–98%.Peak signal to noise ratio and structural similarity index were also used as performance measures for determining segmentation accuracy:95%and 0.95,*** parameters of level set formulation vary for different *** optimization procedure was followed to fine tune *** proposed method was found to be efficient and robust against noisy *** proposed method is adaptive and multimodal.

关键词： Ventricles Atrophy Segmentation Level set Diagnosis

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mechanical and physical characterization of sodium hydroxide treated Borassus fruit fibers

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Journal of Forestry Research 2012年第4期23卷 667-674页

作者： Obi reddy K Shukla m Uma maheswari C Varada Rajulu A Department of mechanical Engineering Technology Doornfontein CampusP.O Box 17011University of JohannesburgJohannesburg 2028South Africa Department of Polymer Science and Technology Sri Krishnadevaraya UniversityAnantapur 515055India

In order to improve the properties by chemical modification and to optimize the alkali concentration, we treated Borassus fruit fine fibers with aqueous sodium hydroxide solutions of different concentra- tions. In each case, the tensile properties of the fibers were determined. The morphology of the untreated and alkali treated fibers was observed using scanning electron microscope. The surface of the fibers became rough on alkali treatment. The tensile properties of the fibers improved on alkali treatment. The fibers attained maximum tensile properties when treated with 15% aqueous sodium hydroxide solution and decreased thereafter. The crystallinity index of the fibers showed a similar trend. The thermal stability of the alkali treated fibers was found to be higher than that of untreated fibers. Further, the char content was maximum for fibers treated with alkali having concentration of 15% and above. The chemical composition indicated that the percentageof a-cellulose was maximum when the fibers were treated with 15% aqueous sodium hydroxide solution and then decreased thereafter thus indicating the beginning of degradation of the fibers at higher concentrations. Thus, the optimum concentration of NaOH was established as 15% for alkali treatment of the Borassus fibers.

关键词： borassus fruit fine fiber chemical composition mercerization spectral analysis tensile properties thermal properties.

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major geologic events of the Cauvery Basin,India and their correlation with global signaturese——A review

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Journal of Palaeogeography 2017年第1期6卷 69-83页

作者： R.Nagendra A.Nallapa reddy Department of Geology Anna UniversityChennai600025India

The present review is aimed at correlating major geologic events of the Cauvery Basin with analogous global episodes. The Cauvery Basin came into existence due to Gondwana break up during Late Jurassic-Early Cretaceous by taphrogenic rift process. The first marine transgression close to Aptian/Albian boundary at the western margin of the basin terminates the syn-rift tectonic phase, which is also precise in adjoining Krishna-Godavari （KG） Basin. Two regional tectonic episodes are well documented in the basin which have global significance viz. （1） A major basinal uplift during late Turonian caused by marion hot mantle plume resulted in widespread subaqueous volcanism in the southern part of the Cauvery Basin. This uplift also ted to relative sea level （RSL） fall of about 100 m in Cauvery and KG Basins and an unconformity of a magnitude of 2.3 ma. The RSL fatt closely correlates with global sea level faU. This volcanic episode also resulted in madagascar detachment from India. （2） The reunion hot mantle plume that ted to Deccan volcanism in central India resulted in E-SE tilt of the Cauvery Basin during upper maastrichtian （CFI-CF3 zones）. This tilt caused a sea level fall of about 80 m and lateral withdrawal of sea by about 50 km developing a major erosional unconformity ranging in magnitude of -1.8-30 my. The magnitude of RSL correlates wetl with global sea level fall. This sea level fall caused widespread development of canyon features in the Cauvery Basin resulting in differential subaqueous erosion. The globally significant ocean anoxic events viz. OAE-Ib, OAE-1d, OAE-2 and OAE-3 are fairly discernible in the Cauvery Basin. The new isotopic palaeotemperature data suggests that southern India and madagascar were located apparently in middle latitudes within the tropical-subtropical climatic zone during Atbian and early maastrichtian. The magnitude of hiatus across K-Pg boundary varying from 0 to 30 ma is estimated based on ptanktic foraminifera for subsurface sec

关键词： Cauvery Basin Correlation Geologic events Global episodes

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Well-being analysis of GSU transformer insulation incorporating the impact on power generation using fuzzy logic

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Frontiers in Energy 2013年第3期7卷 288-299页

作者： Alagarsamy KRISHNAVEL Dusmata Kumar mOHANTA m. Jaya Bharata reddy Department of Electrical and Electronics Engineering Birla Institute ofTechnology Mesra 835215 India Department of Electrical and Electronics Engineering National Instituteof Technology Timchirappalli 620015 India

With the prevailing power scenario, every watt-second of electrical energy has its own merit in satisfying the consumer demand. At the state of such a stringent energy demanding era, failure of a power generation equipment compounds the energy constraints which will not only result in a huge loss of generation but also have an impact on capital revenue. The unexpected failure of generator step-up （GSU） transformer is espe- cially a major disturbance in the power system operation and leads to unscheduled outages with power delivery problems. The time lag in bringing back the equipment in service after rectification or replacement may increase the criticality as the process involves mobilization of spares and maintenance professionals. Hot atmosphere existing in the vicinity of thermal power stations running round-the- clock with more than 100% plant load factor （PLF） increases the thermal stress of the electrical insulation which leads to premature failure of windings, bushings, core laminations, etc. The healthy state of the GSU transformer has to be ensured to minimize the loss of power generation. As the predication related to failure of a GSU transformer is associated with some uncertainties, a fuzzy approach is employed in this paper along with actual field data and case studies for the well-being analysis of GSU transformer.

关键词： generator step-up (GSU) transformer well- being analysis dissolved gases in oil analysis (DGA) tan delta (TD) sweep frequency response analysis (SFRA) fuzzy inference system (FIS)

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Degradation of methylene Blue and Rhodamine B Using a New Visible Light-Responsive Photocatalyst, KSb_2PO_(8-x)N_y

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Acta metallurgica Sinica(English Letters) 2016年第4期29卷 335-343页

作者： G.Ravi CH.Sudhakar reddy K.Sreenu Ravinder Guje Radha Velchuri m.Vithal Department of Chemistry University College of ScienceOsmania University

Potassium phosphatoantimonates, KSb2PO8 （KSbPO） and KSb2PO8-xNy （KSbPON）, are prepared by solidstate method. Urea is employed as a source of nitrogen for N-doping. Structural, morphological and optical properties of both KSbPO and KSbPON are characterized by powder X-ray diffraction （PXRD）, scanning electron microscopy, energydispersive spectroscopy, Fourier transform infrared spectroscopy and UV-visible diffuse reflectance spectroscopy. Both samples are found to crystallize in a monoclinic lattice with Cc space group. The d-lines of KSbPO and KSbPON are refined by least square fitting the PXRD data, using POWD software to obtain their unit cell parameters. The bandgap energy （Eg） of both pristine and N-doped KSbPO is found from their Kubelka-munk plot. The KSbPON/visible photocatalytic degradation of methylene blue and rhodamine B has been investigated in aqueous heterogeneous suspension. The generation of .OH in the presence of KSbPON during the photoreaction is verified by a fluorescence technique using terephthalic acid （TA） as a probe.

关键词： Potassium phosphatoantimonates Characterization Organic dyes Photodegradation

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Extended Deep Learning Algorithm for Improved Brain Tumor Diagnosis System

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Intelligent Automation & Soft Computing 2024年第1期39卷 33-55页

作者： m.Adimoolam K.maithili N.m.Balamurugan R.Rajkumar S.Leelavathy Raju Kannadasan mohd Anul Haq Ilyas Khan ElSayed m.Tag El Din Arfat Ahmad Khan Department of Computer Engineering Government Polytechnic CollegeSevvapetTiruvallurTamil Nadu602025India Department of Computer Science and Engineering KG Reddy College of Engineering and TechnologyHyderabadTelangana500075India Department of Computer Science and Engineering Sri Venkateswara College of EngineeringSriperumbudurChennai602117India Department of Computer Science and Engineering Annamalai UniversityChidambaramTamil Nadu608002India Department of Computer Science and Engineering Aarupadai Veedu Institute of TechnologyVinayaka Mission Research FoundationPaiyanurTamil Nadu603104India Department of Electrical and Electronics Engineering Sri Venkateswara College of EngineeringSriperumbudur602117India Department of Computer Science College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia Department of mathematics College of Science Al-ZulfiMajmaah UniversityAl-Majmaah11952Saudi Arabia Electrical Engineering Department Faculty of Engineering&TechnologyFuture University in EgyptNew Cairo11835Egypt Department of Computer Science College of ComputingKhon Kaen UniversityKhon Kaen40002Thailand

At present,the prediction of brain tumors is performed using machine Learning(mL)and Deep Learning(DL)*** various mL and DL algorithms are adapted to predict brain tumors to some range,some concerns still need enhancement,particularly accuracy,sensitivity,false positive and false negative,to improve the brain tumor prediction system ***,this work proposed an Extended Deep Learning Algorithm(EDLA)to measure performance parameters such as accuracy,sensitivity,and false positive and false negative *** addition,these iterated measures were analyzed by comparing the EDLA method with the Convolutional Neural Network(CNN)way further using the SPSS tool,and respective graphical illustrations were *** results were that the mean performance measures for the proposed EDLA algorithm were calculated,and those measured were accuracy(97.665%),sensitivity(97.939%),false positive(3.012%),and false negative(3.182%)for ten *** in the case of the CNN,the algorithm means accuracy gained was 94.287%,mean sensitivity 95.612%,mean false positive 5.328%,and mean false negative 4.756%.These results show that the proposed EDLA method has outperformed existing algorithms,including CNN,and ensures symmetrically improved *** EDLA algorithm introduces novelty concerning its performance and particular activation *** proposed method will be utilized effectively in brain tumor detection in a precise and accurate *** algorithm would apply to brain tumor diagnosis and be involved in various medical diagnoses *** the quantity of dataset records is enormous,then themethod’s computation power has to be updated.

关键词： Brain tumor extended deep learning algorithm convolution neural network tumor detection deep learning

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