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Machine learning for predicting the outcome of terminal ballistics events

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Small Object Detection via Precise Region-Based Fully Convolutional Networks

Defence technology 2024年第1期

作者： Shannon Ryan Neeraj Mohan Sushma arun.kumar AV Julian Berk Tahrima Hashem Santu Rana Svetha Venkatesh

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Computers, Materials & Continua 2021年第11期69卷 1503-1517页

作者： Dengyong Zhang Jiawei Hu Feng Li Xiangling Ding arun.kumar Sangaiah Victor SSheng Hunan Provincial Key Laboratory of Intelligent Processing of Big Data on Transportation Changsha University of Science and TechnologyChangsha410114China School of Computer and Communication Engineering Changsha University of Science and TechnologyChangsha410114China School of Computer Science and Engineering Hunan University of Science and TechnologyXiangtan411004China School of Computing Science and Engineering Vellore Institute of Technology(VIT)Vellore632014India Department of Computer Science Texas Tech UniversityLubbock79409TXUSA

In the past several years,remarkable achievements have been made in the field of object *** performance is generally improving,the accuracy of small object detection remains low compared with that of large object *** addition,localization misalignment issues are common for small objects,as seen in GoogLeNets and residual networks(ResNets).To address this problem,we propose an improved region-based fully convolutional network(R-FCN).The presented technique improves detection accuracy and eliminates localization misalignment by replacing positionsensitive region of interest(PS-RoI)pooling with position-sensitive precise region of interest(PS-Pr-RoI)pooling,which avoids coordinate quantization and directly calculates two-order integrals for position-sensitive score maps,thus preventing a loss of spatial precision.A validation experiment was conducted in which the Microsoft common objects in context(MS COCO)training dataset was *** showed an accuracy improvement of 3.7%for object detection tasks and an increase of 6.0%for small objects.

关键词： Small object detection precise R-FCN PS-Pr-RoI pooling two-stage detector

An Efficient Hybrid PAPR Reduction for 5G NOMA-FBMC Waveforms

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Computers, Materials & Continua 2021年第12期69卷 2967-2981页

作者： arun.kumar Sivabalan Ambigapathy Mehedi Masud Emad Sami Jaha Sumit Chakravarty Kanchan Sengar Department of Electronics and Communication Engineering JECRC UniversityJaipur303905India Center for System Design Chennai Institute of TechnologyIndia Department of Computer Science College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia Department of Computer Science Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddahSaudi Arabia Department of Electrical and Computer Engineering Kennesaw State UniversityGAUSA

The article introduces Non-Orthogonal Multiple Access(NOMA)and Filter Bank Multicarrier(FBMC),known as hybrid waveform(NOMAFBMC),as two of the most deserving contenders for fifth-generation(5G)*** spectrum access and clampdown of spectrum outflow are unique characteristics of hybrid *** compare the spectral efficiency of Orthogonal Frequency Division Multiplexing(OFDM),FBMC,NOMA,and *** is seen that the hybrid waveform outperforms the existing *** to Average Power Ratio(PAPR)is regarded as a significant issue in multicarrier *** combination of Selective Mapping-Partial Transmit Sequence(SLM-PTS)is an effective way to minimize large peak power *** SLM,PTS,and SLM-PTS procedures are applied to the NOMA-FBMC *** hybrid structure is applied to the existing ***,the correlated factors like Bit Error Rate(BER)and Computational Overhead(CO)are studied and computed for these *** outcome of the work reveals that the NOMA-FBMC waveform coupled with the SLM-PTS algorithm offers superior performance as compared to the prevailing systems.

关键词： 5G NOMA-FBMC SLM-PTS PAPR BER OFDM

Reaction order and neural network approaches for the simulation of COVID-19 spreading kinetic in India

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Infectious Disease Modelling 2020年第1期5卷 737-747页

作者： Sourav Chakraborty arun.kumar Choudhary Mausumi Sarma Manuj kumar Hazarika Department of Food Engineering and Technology Tezpur UniversityAssam784028India Department of Agricultural Engineering North Eastern Regional Institute of Science and Technology(NERIST)Arunachal Pradesh791109India

COVID-19 has created a pandemic situation in the whole *** of COVID-19 spreading rate in the social environment is a challenge for all *** the present study,simulation of the lockdown effect on the COVID-19 spreading rate in India and mapping of its recovery percentage(until May 2020)were *** of the lockdown impact dependent on first order reaction kinetics demonstrated higher effect of lockdown 1 on controlling the COVID-19 spreading rate when contrasted with lockdown 2 and *** decreasing trend was followed for the reaction rate constant of different lockdown stages,the distinction between the lockdown 2 and 3 was *** and feed forward neural network(FFNN)approaches were applied for the simulation of COVID-19 spreading *** case of mathematical approach,exponential model indicated adequate performance for the prediction of the spreading rate *** the FFNN based modeling,1-5-1 was selected as the best architecture so as to predict adequate spreading rate for all the *** architecture also showed effective performance in order to forecast number of cases for next 14 *** recovery percentage was modeled as a function of number of days with the assistance of polynomial ***,the investigation recommends proper social distancing and efficient management of corona virus in order to achieve higher decreasing trend of reaction rate constant and required recovery percentage for the stabilization of India.

关键词： Lock down effect COVID-19 FFNN Recovery percentage

A Comparative Investigation on the Structural,Optical and Electrical Properties of SiO_2-Fe_3O_4 Core-Shell Nanostructures with Their Single Components

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Acta Metallurgica Sinica(English Letters) 2015年第11期28卷 1317-1325页

作者： Neena Bachan A.Asha W.Jothi Jeyarani D.arun.kumar J.Merline Shyla Department of Physics Energy NanoTechnology Centre(ENTeC)Loyola Institute of Frontier Energy(LIFE)Loyola College Department of Physics Dhanalakshmi Srinivasan College of Engineering and Technology Department of Physics Shri Andal Alagar College of Engineering

The SiO2-Fe3O4 core-shell nanostructures were synthesized by sol-gel chemistry. The morphological features of the nanostructures were examined by field emission scanning electron microscopy which revealed the core-shell nature of the nanoparticles. X-ray diffraction studies evidenced the formation of SiO2-Fe3O4 core-shell nanostructures with high degree of homogeneity. The elemental composition of the SiO2-Fe3O4 core-shell nanostructures was determined by energy-dispersive X-ray spectroscopy analysis. Fourier transform infrared spectroscopy showed the Si-O-Fe stretching vibrations. On analysis of the optical properties with UV-Vis spectra and Tauc＇s plot, it was found that the band gap of SiO2-Fe3O4 core-shell nanostructures diminished to 1.5 eV. Investigation of the electrical properties of the core-shell nanostructures using field-dependent conductivity measurements presented a significant increase in photoconductivity as compared to those of its single components, thereby rendering them as promising candidates for application as photo- electrodes in dye-sensitized solar cells.

关键词： Nanostructures Sol-gel chemistry Optical properties X-ray diffraction Electricalproperties

Structural and photoluminescence studies on europium-doped lithium tetraborate(Eu:Li2B4O7)single crystal grown by microtube Czochralski(μT-Cz)technique

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Chinese Physics B 2016年第5期25卷 429-433页

作者： A kumaresh R arun.kumar N Ravikumar U Madhusoodanan B S Panigrahi K Marimuthu M Anuradha GRD Centre for Materials Research PSG College of TechnologyCoimbatoreIndia Department of Physics PSG College of TechnologyCoimbatoreIndia Radiation Safety Division Indira Gandhi Centre for Atomic ResearchKalpakkamIndia Department of Physics Gandhigram Rural UniversityDindigulIndia PSG Institute of Advanced Studies CoimbatoreIndia

Rare earth europium（Eu（3＋））-doped lithium tetraborate（Eu：Li_2B_4O_7） crystal is grown from its stoichiometric melt by microtube Czochralski pulling technique（μT-Cz） for the first time. The grown crystals are subjected to powder x-ray diffraction（PXRD） analysis which reveals the tetragonal crystal structure of the crystals. UV–vis–NIR spectral analysis is carried out to study the optical characteristics of the grown crystals. The crystal is transparent in the entire visible region, and the lower cutoff is observed to be at 304 nm. The existence of BO_3 and BO_4 bonding structure and the molecular associations are analyzed by Fourier transform infrared（FTIR） spectroscopy. The results of excitation and emission-photoluminescence spectra of europium ion incorporated in lithium tetraborate（LTB） single crystal reveal that the observations of peaks at 258,297, and 318 nm in the excitation spectra and peaks at 579, 591, 597, 613, and 651 nm are observed in the emission *** chromaticity coordinates are calculated from the emission spectra, and the emission intensity of the grown crystal is characterized through a CIE 1931（Commission International d＇Eclairage） color chromaticity diagram.

关键词： crystal growth optical material growth from melt photoluminescence study

Fertilization and Soil Ploughing Practices under Changing Physical Environment Lead to Soil Organic Carbon Dynamics under Conservation Agriculture in Rice-Wheat Cropping System: A Scoping Review

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Structural and luminescence enhancement properties of Eu^(3+)/Ag nanocrystallites doped SiO_2-TiO_2 matrices

Agricultural Sciences（农业科学） 2024年第1期

作者： Salwinder Singh Dhaliwal Arvind kumar Shukla Sanjib kumar Behera Sarwan kumar Dubey Agniva Mandal Mehakpreet Kaur Randhawa Sharanjit Kaur Brar Gagandeep Kaur Amardeep Singh Toor Sohan Singh Walia Priyadarshani arun Khambalkar

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Journal of Rare Earths 2013年第5期31卷 441-448页

作者： arun.kumar K V Revathy K P Prathibha Vasudevan Sunil Thomas Biju P R Unnikrishnan N V School of Pure & Applied Physics Mahatma Gandhi University

We reported here the structural and optical characterisation of silver nanocrystallites/Eu3＋：SiO2-TiO2 matrices synthesised through sol-gel route. Structural characterisations were done by using energy dispersive spectroscopy （EDX）, X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, atomic force microscope （AFM） and transmission electron microscopy （TEM） measurements and optical characterisations were performed by absorption and emission spectroscopy. The TEM and XRD measurements confirmed the presence of nanocrystals. A broad absorption band was observed due to surface plasmon resonance of silver nanocrystals. The effect of silver nanocrystals on the emission spectrum of Eu3＋ doped SiO2-TiO2 matrices was discussed. An attempt was made to explain this fluorescence enhancement by invoking phenomena such as energy transfer, asymmetry ratio, surface plasmon, surface roughness, crystallinity and grain boundary. Our analysis, based on the experimental results, suggested that all the phenomena except crystallinity and grain boundary had favourable effects on fluorescence enhancement. We also estimated the relevant parameters associated with the phenomena that affected the fluorescence emission from the Eu3＋ ions in the matrix. It was seen that the theoretical estimate of fluorescence enhancement agreed well with the experimental estimate.

关键词： sol-gel luminescence SiO2-TiO2 silver nanoparticles rare earths

Antioxidant and antipyretic properties of methanolic extract of Amaranthus spinosus leaves

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Asian Pacific Journal of Tropical Medicine 2010年第9期3卷 702-706页

作者： Bagepalli Srinivas Ashok kumar Kuruba Lakshman Jayaveera KN Devangam Sheshadri Shekar Avalakondarayappa arun.kumar Bachappa Manoj Department of Pharmacognosy Sri K.V.College of PharmacyChickballapurKarnatakaIndia Department of Pharmacognosy PES College of PharmacyBangaloreKarnatakaIndia Department of Chemistry Jawaharlal Nehru Technological University of College of EngineeringAnantapurAndhra PradeshIndia Department of Pharmacology Sri K.V.College of PharmacyChickballapurKarnatakaIndia

Objective:Methanolic extract of Amaranthus spinosus（***） leaves was screened for antioxidant and antipyretic ***:Antioxidant activity was measured by l,l-diphenyl-2-picryl-hydrazile（DPPH） free radical scavenging,superoxide anion radical scavenging,hydroxyl free radical scavenging,nitric oxide radical scavenging,2,2 -azinobis-3- ethylbenzothiazole-6-sulfonic acid（ABTS） radical scavenging assays and total phenolic content was also *** activity of methanolic extract of *** was measured by yeast induced pyrexia method at concentration of 200 and 400 mg/kg using paracetamol as standard ***:Methanolic extract of *** showed potent antioxidant *** IC50 value was（87.50±3.52）μg/mL,（98.80±1.40）μg/mL,（106.25±0.20）μg/mL,（88.70±0.62）μg/mL and（147.50±2.61）μg/mL for DPPH,superoxide,hydroxyl,nitric oxide and ABTS radical scavenging *** extract of A spinosus showed significant（P<0.01） antipyretic activity.

关键词： Amaranthus spinosus Antioxidant activity Antipyretic activity