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Chinese Optics Letters 2013年第8期11卷 80-86页

作者： N. r. Senthil kumar A. John Peter Chang Woo Lee Department of Physics RVS School of Engineering College Department of Physics Govt.Arts College Department of Chemical Engineering and Green Energy Center College of EngineeringKyung Hee University

Taking into account anisotropy, nonparabolicity of the conduction band, and geometrical confinement, we discuss the heavy-hole excitonic states in a strained GaxIn1-xAs/GaAs quantum dot for various Ga alloy contents. The strained quantum dot is considered as a spherical InAs dot surrounded by a GaAs barrier material. The dependence of the effective excitonic g-factor as a function of dot radius and Ga ion content is numerically measured. Interband optical energy with and without the parabolic effect is computed using structural confinement. The interband matrix element for different Ga concentrations is also calculated. The oscillator strength of interband transitions on the dot radius is studied at different Ga concentrations in the GaxIn1-xAs/GaAs quantum dot. Heavy-hole excitonic absorption spectra are recorded for various Ga alloy contents in the GaxIn1-xAs/GaAs quantum dot. results show that oscillator strength diminishes when dot size decreases because of the dominance of the quantum size effect. Furthermore, exchange enhancement and exchange sDlitting increase as exciton confinement inereases.

关键词： GaAs effect of geometrical confinement on exciton g-factor Optical properties of excitons in strained Gax In1-x As/GaAs quantum dot

Feeder and post Deccan Trap dyke activities in the northern slope of the Satpura Mountain： Evidence from new 40Ar-39Ar ages

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Geoscience Frontiers 2017年第3期8卷 483-492页

作者： J.P.Shrivastava r.kumar N.rani Department of Geology University of Delhi

We present new 40Ar-39Ar plagioclase crystallization ages from the dykes exposed at the northern slope of the Satpura Mountain range near Betul-Jabalpur-Pachmarhi area, - 800 km NE of the Western Ghats escarpment. Among the two plateau ages, the first age of 66.56 ± 0.42 Ma from a dyke near Mohpani village represents its crystallization age which is either slightly older or contemporaneous with the nearby Mandla lava flows （63-65 Ma）. We suggest that the Mohpani dyke might be one of the feeders for the surrounding lava flows as these lavas are significantly younger than the majority of the main Deccan lavas of the Western Ghats （66.38-65.54 Ma）. The second age of 56.95 -- 1.08 Ma comes from a younger dyke near Olini village which cuts across the lava flows of the area. The age correlates well with the Mandla lavas which are chemically similar to the uppermost Poladpur, Ambenali and Mahabaleshwar Formation lavas of SW Deccan. Our study shows that the dyke activities occurred in two phases, with the second one representing the terminal stage.

关键词： 40Aro39Ar ages Deccan dykes Betul-Jabalpur-Pachmarhi area Narmada-Tapi dyke system

Wave propagation at interface of heat conducting micropolar solid and fluid media

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Applied Mathematics and Mechanics(English Edition) 2011年第7期32卷 881-902页

作者： r.kumar M.KAUr S.C.rAJVANSHI Department of Mathematics Kurukshetra UniversityKurukshetra 136119India Department of Applied Sciences Guru Nanak Dev Engineering CollegeLudhianaPunjab 141008India Department of Applied Sciences Gurukul VidyapeethInstitute of Engineering and TechnologyBanurPunjab 140601India

The present investigation is concerned with the wave propagation at an interface of a micropolar generalized thermoelastic solid half space and a heat conducting micropolar fluid half space. reflection and transmission phenomena of plane waves are investigated, which impinge obliquely at the plane interface between a micropolar generalized thermoelastic solid half space and a heat conducting micropolar fluid half space. The incident wave is assumed to be striking at the interface after propagating through the micropolar generalized thermoelastic solid. The amplitude ratios of various reflected and transmitted waves are obtained in a closed form. It is found that they are a function of the angle of incidence and frequency and are affected by the elastic properties of the media. Micropolarity and thermal relaxation effects are shown on the amplitude ratios for a specific model. The results of some earlier literatures are also deduced from the present investigation.

关键词： micropolar solid micropolar fluid thermoelastic reflection coefficient,transmission coefficient half space

Thermomagnetic effect with microtemperature in a semiconducting photothermal excitation medium

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Applied Mathematics and Mechanics(English Edition) 2018年第6期39卷 783-796页

作者： K.LOTFY r.kumar W.HASSAN M.GABr Department of Mathematics Faculty of ScienceZagazig University Department of Mathematics Kurukshetra University Mathematics and Physics Department Faculty of EngineeringPort Said University

The main goal of this paper is to focus on the investigation of interaction between a magnetic field and elastic materials with microstructure, whose microelements possess microtemperatures with photothermal excitation. The elastic-photothermal prob- lem in one-dimension is solved by introducing photothermal excitation at the free surface of a semi-infinite semiconducting medium （semiconductor rod）. The integral transform technique is used to solve the governing equations of the problem under the effect of the microtemperature field. The analytical expressions for some physical quantities in the physical domain are obtained with the heating boundary surface and free traction. The numerical inversion technique is used to obtain the resulting quantities in the physical domain. The obtained numerical results with some comparisons are discussed and shown graphically.

关键词： photothermal theory carrier density magnetic field microtemperature Laplace transform

Adelfa:a futuristic biodiesel fuel for DI diesel engines:a comparative experimental investigation

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Chinese Science Bulletin 2014年第9期59卷 924-930页

作者： A.r.Pradeep kumar K.Annamalai S.r.Premkartikkumar Department of Automobile Engineering Anna University MIT Campus Chennai India

Biodiesel fuel is found to be a promising alternative for the petroleum diesel based on the results published by the researchers for a *** fuel is renewable and non degradable *** countries use biodiesel fuel for automotives to meet the crisis due to the depletion of the petroleum fuel and to meet the stringent emission norms Various researches have been carried out with different biodiesel fuels with vegetable oil as the source and appreciable results were *** biodiesel fuels which have been already tested are Jatropha,Pongamia,Mahua,neem,cotton seed,*** this experimental work,Adelfa biodiesel blend is used as the test *** emission and performance characteristics were compared with three other different biodiesel fuel *** results imply that Adelfa biodiesel(Nerium oil methyl ester)can be a futuristic biodiesel fuel,which has a good compatibility with the direct injection(DI)diesel engine without any major ***,Adelfa can be cultivated in a non agricultural land with fewer sources of *** is widely spread over all major countries of *** investigations have been carried out on a single cylinder DI diesel engine with standard engine *** this experimental work,various Adelfa biodiesel blends is compared with reference fuel(diesel)to choose the best blend which gives a closer performance to *** comparative analysis with other biodiesel fuels has also been done and results have been discussed.

关键词：直喷式柴油机生物柴油柴油燃料对比实验混合燃料排放标准石油燃料实验工作

Marine Predators Algorithm with Deep Learning-Based Leukemia Cancer Classification on Medical Images

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 893-916页

作者： Sonali Das Saroja kumar rout Sujit kumar Panda Pradyumna kumar Mohapatra Abdulaziz S.Almazyad Muhammed Basheer Jasser Guojiang Xiong Ali Wagdy Mohamed Department of Computer Science&Engineering Gandhi Institute for TechnologyBPUTBhubaneswar752054India Department of Information Technology Vardhaman College of Engineering(Autonomous)Hyderabad501218TelanganaIndia Department of Electronic&Communication Engineering Vedang Institute of TechnologyBhubaneswar752010India Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh11543Saudi Arabia Department of Computing and Information Systems School of Engineering and TechnologySunway UniversityJalan UniversitiBandar SunwaySelangor Darul Ehsan47500Malaysia research Centre for Human-Machine Collaboration(HUMAC) School of Engineering and TechnologySunway UniversityJalan UniversitiBandar SunwaySelangor Darul Ehsan47500Malaysia Guizhou Key Laboratory of Intelligent Technology in Power System College of Electrical EngineeringGuizhou UniversityGuiyang550025China Operations research Department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Applied Science research Center Applied Science Private UniversityAmman11931Jordan

In blood or bone marrow,leukemia is a form of cancer.A person with leukemia has an expansion of white blood cells(WBCs).It primarily affects children and rarely affects *** depends on the type of leukemia and the extent to which cancer has established throughout the *** leukemia in the initial stage is vital to providing timely patient *** image-analysis-related approaches grant safer,quicker,and less costly solutions while ignoring the difficulties of these invasive *** can be simple to generalize Computer vision(CV)-based and image-processing techniques and eradicate human *** researchers have implemented computer-aided diagnosticmethods andmachine learning(ML)for laboratory image analysis,hopefully overcoming the limitations of late leukemia detection and determining its *** study establishes a Marine Predators Algorithm with Deep Learning Leukemia Cancer Classification(MPADL-LCC)algorithm onMedical *** projectedMPADL-LCC system uses a bilateral filtering(BF)technique to pre-process medical *** MPADL-LCC system uses Faster SqueezeNet withMarine Predators Algorithm(MPA)as a hyperparameter optimizer for feature ***,the denoising autoencoder(DAE)methodology can be executed to accurately detect and classify leukemia *** hyperparameter tuning process using MPA helps enhance leukemia cancer classification *** results are compared with other recent approaches concerning various measurements and the MPADL-LCC algorithm exhibits the best results over other recent approaches.

关键词： Leukemia cancer medical imaging image classification deep learning marine predators algorithm

Negative Stiffness Mechanism on An Asymmetric Wave Energy Converter by Using A Weakly Nonlinear Potential Model

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China Ocean Engineering 2024年第4期38卷 689-700页

作者： Sunny kumar POGULUrI Dongeun KIM Yoon Hyeok BAE Department of Ocean Engineering IIT MadrasChennaiIndia Multidisciplinary Graduate School Program for Wind Energy Jeju National UniversityJejuRepublic of Korea Mechanical and System Design Engineering Hongik UniversitySeoulRepublic of Korea

Salter's duck,an asymmetrical wave energy converter(WEC)device,showed high efficiency in extracting energy from 2D regular waves in the past;yet,challenges remain for fluctuating wave *** can potentially be addressed by adopting a negative stiffness mechanism(NSM)in WEC devices to enhance system efficiency,even in highly nonlinear and steep 3D waves.A weakly nonlinear model was developed which incorporated a nonlinear restoring moment and NSM into the linear formulations and was applied to an asymmetric WEC using a time domain potential flow *** model was initially validated by comparing it with published experimental and numerical computational fluid dynamics *** current results were in good agreement with the published *** was found that the energy extraction increased in the range of 6%to 17%during the evaluation of the effectiveness of the NSM in regular *** irregular wave conditions,specifically at the design wave conditions for the selected test site,the energy extraction increased by 2.4%,with annual energy production increments of approximately *** findings highlight the potential of NSM in enhancing the performance of asymmetric WEC devices,indicating more efficient energy extraction under various wave conditions.

关键词： asymmetric wave energy converter negative stiffness mechanism weakly nonlinear potential flow power

Microstructure Evolution during Friction Stir Welding of Aluminum Alloy AA2219

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Journal of Materials Science & Technology 2010年第8期26卷 747-753页

作者： K.S.Arora S.Pandey M.Schaper r.kumar Mechanical Engineering Department Indian Institute of Technology Institut fuer Werkstoffwissenschaft Technische Universitaet Dresden Institut fuer Sicherheitsforschung Forschungszentrum Dresden-Rossendorf Engineering Division National Metallurgical Laboratory

The characterization of microstructure evolution in friction stir welded aluminum alloy was carried out by optical microscopy （OM） and transmission electron microscopy （TEM） and electron backscatter diffraction （EBSD）. The weld nugget consisted of very fine equiaxed grains and experienced dissolution of nearly half of metastable precipitates into the matrix during welding. Thermomechanically affected zone （TMAZ） also experienced dissolution of precipitates but to a lesser extent whereas coarsening of precipitates was observed in heat affected zone （HAZ）. Grain boundary misorientation measurements using EBSD indicated continuous dynamic recrystallization as the underlying mechanism for the fine equiaxed nugget grains. The yield and tensile strength of the weld decreased with comparison to base material. But due to the decrease of grain size and the dissolution of second phase precipitates, an increased Charpy energy value was observed in the weld n u gget.

关键词： Friction stir welding AA2219 Precipitates Vickers hardness Tensile testing Charpy impact energy

Performance, emission and combustion characteristics of CI engine fuelled with diesel and hydrogen

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Frontiers in Energy 2015年第4期9卷 486-494页

作者： r. Senthil kumar M. LOGANATHAN E. James GUNASEKArAN Department of Mechanical Engineering Annamalai University Chi- dambaram 608002 India

Hydrogen （H2） is being considered as a primary automotive fuel and as a replacement for conventional fuels. Some of the desirable properties, like high flame velocity, high calorific value motivate us to use hydrogen fuel as a dual fuel mode in diesel engine. In this experiment, hydrogen was inducted in the inlet manifold with intake air. The experiments were conducted on a four stroke, single cylinder, water cooled, direct injection （DI）, diesel engine at a speed of 1500r/min. Hydrogen was stored in a high pressure cylinder and supplied to the inlet manifold through a water-and-air-based flame arrestor. A pressure regulator was used to reduce the cylinder pressure from 140 bar to 2 bar. The hydrogen was inducted with a volume flow rate of 41 pm, 61 pm and 81 pm, respectively by a digital volume flow meter. The engine performance, emission and combustion parameters were analyzed at various flow rates of hydrogen and compared with diesel fuel operation. The brake thermal efficiency （BTE） was increased and brake specific fuel consumption （BSFC） decreased for the hydrogen flow rate of 81 pm as compared to the diesel and lower volume flow rates of hydrogen. The hydrocarbon （HC） and carbon monoxide （CO） were decreased and the oxides of nitrogen （NOx） increased for higher volume flow rates of hydrogen compared to diesel and lower volume flow rates of hydrogen. The heat release rate and cylinder pressure was increased for higher volume flow rates of hydrogen compared to diesel and lower volume flow rates of hydrogen.

关键词： hydrogen brake thermal efficiency crankangle compressed ignition (CI)

Implications of regional identity for neural stem and progenitor cell transplantation in the injured or diseased nervous system

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Neural regeneration research 2024年第4期19卷 715-716页

作者： Prakruthi Amar kumar Jennifer N.Dulin Department of Biology Texas A&M UniversityCollege Station Texas A&M Institute for Neuroscience Texas A&M UniversityCollege Station

Neural stem and progenitor cell(NSPC)transpla ntation has emerged as a promising therapeutic strategy for replacing lost neuronal populations and repairing damaged neural circuits following nervous system injury and disease.A great deal of experimental work has investigated the biology of NSPC grafting in preclinical animal models;more recently.

关键词： neural system injured