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Adaptive Linear Quadratic Regulator for Continuous-Time Systems With Uncertain Dynamics

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IEEE/CAA Journal of Automatica Sinica 2020年第3期7卷 833-841页

作者： sumit kumar Jha Shubhendu Bhasin IEEE Department of Electronics and Communication Engineering Motilal Nehru National Institute of Technology AllahabadPrayagraj-211004India Department of Electrical Engineering Indian Institute of Technology DelhiNew Delhi-110016India

In this paper, adaptive linear quadratic regulator(LQR) is proposed for continuous-time systems with uncertain dynamics. The dynamic state-feedback controller uses inputoutput data along the system trajectory to continuously adapt and converge to the optimal controller. The result differs from previous results in that the adaptive optimal controller is designed without the knowledge of the system dynamics and an initial stabilizing policy. Further, the controller is updated continuously using input-output data, as opposed to the commonly used switched/intermittent updates which can potentially lead to stability issues. An online state derivative estimator facilitates the design of a model-free controller. Gradient-based update laws are developed for online estimation of the optimal gain. Uniform exponential stability of the closed-loop system is established using the Lyapunov-based analysis, and a simulation example is provided to validate the theoretical contribution.

关键词： Adaptive optimal control continuous policy update linear quadratic regulator uncertain system dynamics

MOLECULAR DYNAMICS SIMULATION OF POLYMER/CARBON NANOTUBE COMPOSITES

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Acta Mechanica Solida Sinica 2015年第4期28卷 409-419页

作者： sumit Sharma Rakesh Chandra Pramod kumar Navin kumar Department of Mechanical Engineering Dr.B.R.Ambedkar National Institute of Technology School of Mechanical Materials & Energy Engineering (SMMEE) Indian Institute of Technology

In this paper, we present classical molecular dynamics （MD） simulations of model polymer/CNT composites constructed by embedding a single wall （10,10） CNT into two different amorphous polymer matrices： poly（methyl methacrylate） and poly{（m-phenylene-vinylene）-co- [（2,5-dioctoxy-p-phenylene） vinylene]}, respectively, with different volume fractions. The simulation results support the idea that it is possible to use CNTs to mechanically reinforce an appropri- ate polymer matrix, especially in the longitudinal direction of the nanotube. The comparison of the simulation results with the macroscopic rule-of-mixtures for composite systems showed that for strong interfacial interactions, there can be large deviations of the results from the rule-of- mixtures. In order to verify this study, results obtained have been compared with those given by Elliott and Han （2007）.

关键词： nano-structures elasticity mechanical properties computational modeling

INFLUENCE OF RIGID BOUNDARY ON THE LOVE WAVE PROPAGATION IN ELASTIC LAYER WITH VOID PORES

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Acta Mechanica Solida Sinica 2013年第5期26卷 551-558页

作者： sumit kumar Vishwakarma Shishir Gupta Dinesh kumar Majhi Department of Applied Mathematics Indian School of Mines Department of Mathematics Birla Institute of Technology and Science

In this paper, a mathematical model for Love wave propagation in a porous elastic layer under a rigid boundary resting over a poro-elastic half-space has been developed. The study shows that such a medium transmits two types of Love waves. The first front depends on the change in volume fraction of the pores whereas the second front depends upon the modulus of rigidity of the elastic matrix of the medium and is the same as the Love wave in an elastic layer over an elastic half-space. It is observed that the first front is many times faster than the shear wave in the medium with void pores due to the change in the volume fraction of the pores and is significant.

关键词： Love waves void pores volume fraction rigid boundary wave front

THE GENERALIZED HYPERSTABILITY OF GENERAL LINEAR EQUATION IN QUASI-2-BANACH SPACE

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Acta Mathematica Scientia 2022年第4期42卷 1357-1372页

作者： Ravinder kumar SHARMA sumit CHANDOK School of Mathematics Thapar Institute of Engineering and TechnologyPatiala-147004India

In this paper,we study the hyperstability for the general linear equation f(ax+by)=Af(x)+Bf(y)in the setting of complete quasi-2-Banach *** first extend the main fixed point result of Brzdek and Ciepliński(Acta Mathematica Scientia,2018,38 B(2):377-390)to quasi-2-Banach spaces by defining an equivalent quasi-2-Banach *** we use this result to generalize the main results on the hyperstability for the general linear equation in quasi-2-Banach *** results improve and generalize many results of literature.

关键词： Hyperstability quasi-2-Banach spaces fixed point general linear equation

Neuroprotective potential of Quercetin in combination with piperine against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity

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Neural Regeneration Research 2017年第7期12卷 1137-1144页

作者： Shamsher Singh sumit Jamwal Puneet kumar Department of Pharmacology I.S.F College of Pharmacy Ferozepur Road Moga Punjab India I.K. Gujral Punjab Technical University Jalandhar Punjab India

1-Methy-4-phenyl-1,2,3,6-tetrahydropyridine（MPTP）is a neurotoxin that selectively damages dopaminergic neurons in the substantia nigra pars compacta and induces Parkinson＇s like symptoms in ***（QC）is a natural polyphenolic bioflavonoid with potent antioxidant and anti-inflammatory properties but lacks of clinical attraction due to low oral *** is a well established bioavailability enhancer used pre-clinically to improve the bioavailability of antioxidants（e.g.,Quercetin）.Therefore,the present study was designed to evaluate the neuroprotective potential of QC together with piperine against MPTP-induced neurotoxicity in ***（100μg/μL/rat,bilaterally）was injected intranigrally on days 1,4 and 7 using a digital stereotaxic ***（25 and 50 mg/kg,intragastrically）and QC（25 mg/kg,intragastrically）in combination with piperine（2.5 mg/kg,intragastrically）were administered daily for 14 days starting from day 8 after the 3^（rd） injection of *** day 22,animals were sacrificed and the striatum was isolated for oxidative stress parameter（thiobarbituric acid reactive substances,nitrite and glutathione）,neuroinflammatory cytokine（interleukin-1β,interleukin-6,and tumor necrosis factor-α）and neurotransmitter（dopamine,norepinephrine,serotonin,gamma-aminobutyric acid,glutamate,3,4-dihydroxyphenylacetic acid,homovanillic acid,and 5-hydroxyindoleacetic acid）*** infusion of MPTP into substantia nigra pars compacta led to significant motor deficits as evidenced by impairments in locomotor activity and rotarod performance in open field test and grip strength and narrow beam walk *** QC（25 and 50 mg/kg）and QC（25 mg/kg）in combination with piperine（2.5 mg/kg）,in particular the combination therapy,significantly improved MPTP-induced behavioral abnormalities in rats,reversed the abnormal alterations of neurotransmitters in the striatum,and alleviated oxidative stress and inflammatory response in the *** f

关键词： nerve regeneration 1-methy-4-phenyl-1,2,3,6-tetrahydropyridine Quercetin Piperine Parkinson'sdisease excitotoxicity oxido-nitrosative stress neurotransmitters neural regeneration

A Constant Gain and Miniaturized Antipodal Vivaldi Antenna for 5G Communication Applications

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Computers, Materials & Continua 2022年第12期73卷 4909-4921页

作者： Amruta SDixit sumit kumar Shabana Urooj Symbiosis Institute of Technology Symbiosis International(Deemed University)Pune412115India Department of Electrical Engineering College of EngineeringPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia

This paper proposes a stable gain and a compact Antipodal Vivaldi Antenna(AVA)for a 38GHz band of 5G communication.A novel compact AVA is designed to provide constant gain,high front to back ratio(FBR),and very high *** performance of the proposed AVA is enhanced with the help of a dielectric lens(DL)and corrugations.A rectangular-shaped DL is incorporated in conventional AVA(CAVA)to enhance its gain up to 1 dBi and the bandwidth by 1.8 ***,the rectangular corrugations are implemented in CAVA with lens(CAVA-L)to further improve the gain and *** proposed AVA with lens and corrugations(AVA-LC)gives a constant and high gain of 8.2 to 9 *** designed AVA-LC operates from 34 to 45GHz frequency which covers 38GHz(37.5 to 43.5 GHz)band of 5G ***,the presented AVA-LC mitigates the back lobe and sidelobe levels,resulting in FBR and efficiency *** FBR is in the range of 12.2 to 22 dB,and efficiency is 99%,almost *** AVA-LC is fabricated on Roger’s RT/duroid 5880 substrate,and it is tested to verify the simulated *** proposed compact AVA-LC with high gain,an improved FBR,excellent efficiency,and stable radiation patterns is suitable for the 38GHz band of 5G devices.

关键词： Antipodal Vivaldi Antenna(AVA) constant gain dielectric lens(DL) 5G communication corrugations front to back ratio(FBR)

Impact of Hierarchical Architecture of Cryptotermes brevis Wing on the Modulation of Bacterial Adhesion

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Journal of Bionic Engineering 2022年第2期19卷 516-529页

作者： Sanjeev kumar Paikra sumit Mukherjee Nibedita Nayak Janmejaya Bag Monalisa Mishra Neural Developmental Biology Laboratory Department of Life ScienceNational Institute of Technology769008RourkelaSundergarhOdishaIndia

The wing architecture is an inspiration to fabricate novel materials with exquisite *** current study characterizes the structure and biological function of a termite’s *** topography of the surface of the wing was studied by electron microscopy,and surface *** physicochemical property of the surface was analyzed by Fourier transform infrared spectroscopy,X-ray diffraction spectroscopy,energy-dispersive X-ray spectroscopy,and gas chromatography-mass spectrometry analysis of the epicuticle *** Contact Angle measurement confirmed the hydrophobicity of the wing *** microorganisms come in contact with the surface of the wing,they adhere to the wing surface due to cell surface properties of their own and the surface chemistry of the *** current study reported the adhesion behavior of two bacterial *** bactericidal activity of the wing was confirmed by counting the bacterial cell viability and examination under a confocal laser scanning *** of bacteria was observed under the electron *** oxidative stress,the topography of the wing,and the surface chemistry of the wing are the crucial factors that induce bactericidal *** nanostructure along with the chemical composition of the wing can be mimicked for the fabrication of novel material with antibacterial properties.

关键词： Bacterial adhesion Bactericidal Chitin Nanostructure Pseudomonas aeruginosa Staphylococcus aureus

Appraisal of pollution and health risks associated with coal mine contaminated soil using multimodal statistical and Fuzzy-TOPSIS approaches

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 101-115页

作者： sumit kumar Sonali Banerjee Saibal Ghosh Santanu Majumder Jajati Mandal Pankaj kumar Roy Pradip Bhattacharyya Agricultural and Ecological Research Unit Indian Statistical InstituteGiridih815301India Department of Life and Environmental Sciences Bournemouth University(Talbot Campus)Fern BarrowPooleBH12 5BBUK School of Sciences Engineering & EnvironmentUniversity of SalfordSalfordM5 4QJUK School of Water Resource Engineering Jadavpur UniversityKolkata700032India School of Environmental Studies Jadavpur UniversityKolkata700032India

The present study assesses the concentration,probabilistic risk,source classification,and dietary risk arising from heavy metal(HMs)pollution in agricultural soils affected by coal mining in eastern part of *** of soil and rice plant indicated significantly elevated levels of HMs beyond the permissible limit in the contaminated zones(zone 1:PbSoil:108.24±72.97,CuSoil:57.26±23.91,CdSoil:8.44±2.76,CrSoil:180.05±46.90,NiSoil:70.79±25.06 mg/kg;PbGrain:0.96±0.8,CuGrain:8.6±5.1,CdGrain:0.65±0.42,CrGrain:4.78±1.89,NiGrain:11.74±4.38 mg/*** 2:PbSoil:139.56±69.46,CuSoil:69.89±19.86,CdSoil:8.95±2.57,CrSoil:245.46±70.66,NiSoil:95.46±22.89 mg/kg;PbGrain:1.27±0.84,CuGrain:7.9±4.57,CdGrain:0.76±0.43,CrGrain:8.6±1.58,NiGrain:11.50±2.46 mg/kg)compared to the uncontaminated zone(zone 3).Carcinogenic and non-carcinogenic health risks were computed based on the HMs concentration in the soil and rice grain,with Pb,Cr,and Ni identified as posing a high risk to human *** Carlo simulation,the solubility-free ion activity model(FIAM),and severity adjusted margin of exposure(SAMOE)were employed to predict health *** hazard quotient(HQ)values for Ni,Cr,Cd,and Pb were>1,indicating a significant non-carcinogenic ***(risk thermometer)results for contaminated zones ranged from low to moderate risk(CrSAMOE:0.05,and NiSAMOE:0.03).Fuzzy-TOPSIS and variable importance plots(from random forest)showed that Ni and Cr were mostly responsible for the toxicity in the rice plant,respectively.A self-organizing map for source classification revealed common origin for the studied HMs with zone 2 exhibiting the highest *** positive matrix factorization model for the source apportionment identified coal mining and transportation as the predominant sources of *** distribution analysis indicated higher contamination near mining sites as compared to distant sampling ***,this study will aid environmental scientists and policymakers controllin

关键词： Coal mine Free ion activity model Monto Carlo Simulation Pollution and Health risk Fuzzy-TOPSIS

PAPR Reduction Using Advanced Partial Transmission Scheme for 5G Waveforms

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Computer Systems Science & Engineering 2022年第8期42卷 483-492页

作者： Arun kumar sumit Chakravarty SSuganya Mehedi Masud Sultan Aljahdali Department of Electronics and Communication Engineering JECRC UniversityJaipur303905INDIA Department of Electrical and Computer Engineering Kennesaw State UniversityGAUSA Electronics and Communication Engineering CMR Institute of TechnologyBangaloreINDIA Department of Computer Science College of Computers and Information TechnologyTaif University11099Saudi Arabia

The implementation of Peak Average to Power Ratio(PAPR)reduction technologies will play an important role in the regularization of Fifth Generation(5G)radio *** reduction in the advanced waveform will be the key part of designing a 5G network for different *** work introduces the simulation of an Advanced Partial Transmission Sequence(A-PTS)reduction techniques for Orthogonal Frequency Division Multiplexing(OFDM)and Filter Bank Multi-Carrier(FBMC)transmission *** the projected A-PTS,the FBMC signals are mapped into the number of sub-blocks and Inverse Fast Fourier transform(IFFT)is performed to estimate the high peak power in the time *** FBMC sub-blocks are multiplied with the phase elements to achieve an optimal PAPR value.A MATLAB 2014v simulation is used to estimate the PAPR,Bit Error Rate(BER),Error Vector Magnitude(EVM),and Modulation Error Rate(MER)performance of the proposed reduction *** simulated result reveals that the performance of the projected algorithm is better than the conventional algorithms.

关键词： PAPR PTS OFDM FBMC 5G