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Protection and Control of Modern Power Systems 2022年第1期7卷 490-507页

作者： Neelesh kumar Gupta Manoj kumar Kar arun kumar singh Department of Electrical Engineering NIT JamshedpurJamshedpurJharkhand 831014India

This paper proposes an improved sine-cosine algorithm(ISCA)based 2-DOF-PID controller for load frequency control.A three-area test system is built for study,while some physical constraints(nonlinearities)are considered for the investigation of a realistic power *** proposed method is used as the parameter optimizer of the LFC control-ler in different *** 2-DOF-PID controllers are used because of their capability of fast disturbance rejection without significant increase of overshoot in set-point *** 2-DOF-PID controllers’efficacy is observed by examining the responses with the outcomes obtained with PID and FOPID *** simulation results with the suggested scheme are correlated with some of the existing algorithms,such as SCA,SSA,ALO,and PSO in three dif-ferent scenarios,i.e.,a disturbance in two areas,in three areas,and in the presence of physical *** addition,the study is extended to a four-area power *** analysis is performed using the Wilcoxon Sign Rank Test(WSRT)on 20 independent *** confirms the supremacy of the proposed method.

关键词： 2-DOF-PID FOPID Load frequency control WSRT Statistical analysis Improved sine-cosine algorithm

Channel estimation and channel tracking for correlated block-fading channels in massive MIMO systems

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Digital Communications and Networks 2018年第2期4卷 138-147页

作者： Suresh Dahiya arun kumar singh Department of Electrical Engineering Indian Institute of Technology Jodhpur Rajasthan 342011 India

This paper presents a channel estimation and tracking method for correlated block-fading channels in massive MIMO wireless cellular systems. In order to conserve resources, the proposed algorithm requires the uplink pilot signal only once, at the start of communication. By utilizing the temporal correlation between consecutive Resource Blocks （RBs） and the error correction capability of turbo codes, the channel matrix in subsequent RBs is estimated at the Base Station （BS） itself using the uplink data of current the RB and the estimated channel matrix of previous the RB. Compared to existing blind estimation methods, the proposed method places fewer limitations on the system settings such as the number of BS antennas, the number of users, and the number of coherent channel usage compared to existing blind estimation methods. Simulation results show that the proposed algorithm provides better performance for a moderate RB size, a high-order of QAM scheme, and a smaller ratio of the number of BS antennas and mobile terminals （N/K）. For a reasonably small N/K （order of 10）, the proposed scheme achieves a lower symbol error probability than the conventional pilot-based estimation approach.

关键词： Massive MIMO Channel estimation Resource block Turbo coding Mobile terminal

Fabrication, characterization, numerical simulation and compact modeling of P3HT based organic thin film transistors

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Journal of Semiconductors 2021年第7期42卷 93-105页

作者： Shubham Dadhich A.D.D.Dwivedi arun kumar singh School of Electronics Engineering Vellore Institute of Technology(VIT)VelloreTN-632014India Department of Pure and Applied Physics Guru Ghasidas Vishwavidyalaya Bilaspur(C.G.)495009India

This paper presents the fabrication,characterization and numerical simulation of poly-3-hexylthiophene(P3HT)-based bottom-gate bottom-contact(BGBC)organic thin film transistors(OTFTs).The simulation is based on a drift diffusion charge transport model and density of defect states(DOS)for the traps in the band gap of the P3HT based *** combines two mobility models,a hopping mobility model and the Poole-Frenkel mobility *** also describes the defect density of states(DOS)for both tail and deep *** model takes into account all the operating regions of the OTFT and includes sub-threshold and above threshold characteristics of *** model has been verified by comparing the numerically simulated results with the experimental *** model is also used to simulate different structure in four configurations of OTFT ***-gate bottom-contact(BGBC),bottom-gate top-contact(BGTC),top-gate bottom-contact(TGBC)and top-gate top-contact(TGTC)configurations of the *** also present the compact modeling and model parameter extraction of the P3HT-based *** extracted compact model has been further applied in a p-channel OTFT-based inverter and three stage ring oscillator circuit simulation.

关键词： film characterization numerical

Insect feeding deterrent and growth inhibitory activities of scopoletin isolated from Artemisia annua against Spilarctia obliqua （Lepidoptera： Noctuidae）

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Insect Science 2011年第2期18卷 189-194页

作者： arun kumar Tripathi Rajendra singh Bhakuni Shikha Upadhyay Rashmi Gaur Central Institute of Medicinal and Aromatic Plants Lucknow India

Artemisia annua （Asteraceae） is well known for its antimalarial activities due to presence of the compound artemisinin. We isolated a methoxy coumarin from the stem part of A. annua and confirmed its identity as scopoletin through mass spectral data. The structure was established from 1H-nuclear magnetic resonance （NMR）, 13C-NMR. The compound scopoletin was evaluated for its feeding deterrence and growth inhibitory potential against a noxious lepidopteran insect, Spilartctia obliqua Walker. Scopoletin gave FD50（feeding deterrence of 50%） value of 96.7 μg/g diet when mixed into artificial diet. S. obliqua larvae （12-day-old） exposed to the highest concentration （250μg/g diet） of scopoletin showed 77.1% feeding-deterrence. In a growth inhibitory assay, scopoletin provided 116.9% growth inhibition at the highest dose of 250μg/g diet with a GI50 （growth inhibition of 50%） value of 20.9μg/g diet. Statistical analysis showed a concentrationdependent dose response relationship toward both feeding deterrent and growth inhibitory activities. Artemisinin is found mainly in the leaves of A. annua and not in the stems, which are typically discarded as waste. Therefore identification of scopoletin in stems of A. annua may be important as a source of this material for pest control.

关键词： Artemisia annua feeding deterrent growth inhibitor scopoletin Spilartiaobliqua

Mechanical behaviors of deep pillar sandwiched between strong and weak layers

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第5期15卷 1111-1126页

作者： Sahendra Ram Petr Waclawik Jan Nemcik Radovan Kukutsch Ashok kumar arun kumar singh Libin Gong Department of Mining Engineering National Institute of TechnologyRourkelaOdishaIndia Institute of Geonics The Czech Academy of SciencesOstravaCzech Republic University of Wollongong WollongongAustralia CSIR-Central Institute of Mining and Fuel Research DhanbadJharkhandIndia Department of Mining Engineering Indian Institute of Technology(Indian School of Mines)DhanbadJharkhandIndia

A variety of coal room and pillar mining methods have been efficiently practiced at depths of up to 500 m with least strata mechanics ***,for the first time,this method was trialled at depths of 850 e900 m in CSM mine of Czech *** rhomboid-shaped coal pillars with acute corners of 70,surrounded with 5.2 m wide and 3.5e4.5 m high mine roadways,were *** were developed in a staggered manner with their size variation in the Panel II from 83 m×25 m to 24 m×20 m(corner to corner)and Panel V from 35 m×30 m to 26 m×16 *** seam inclined at 12was affected by the unusual slippery slickenside roof bands and sometimes in the floor levels with high vertical stress below strong and massive sandstone *** order to ensure safety,pillars in both the panels were continuously monitored using various geotechnical instruments measuring the induced stresses,side spalling and roof *** panels suffered high amounts of mining induced stress and pillar failure with side-spalling up to 5 m from all *** fracturing of coal pillar sides was controlled by fully encapsulated steel *** induced stress kept increasing with the progress of development of pillars and *** installed in the pillar failed to monitor actual induced stress due to fracturing of coal mass around it which created an apprehension of pillar failure up to its core due to high vertical mining induced *** risk was reduced by carrying out scientific studies including the three-dimensional numerical models calibrated with data from the instrumented *** attempt has been made to study the behavior of coal pillars and their yielding characteristics at deeper cover based on field and simulation results.

关键词： Pillar yielding mechanisms Great depth Numerical modeling Induced stress Pillar dilation Slippery slickenside layer

Effect of Inclined Tension Crack on Rock Slope Stability by SSR Technique

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Intelligent Automation & Soft Computing 2023年第4期36卷 1205-1214页

作者： Ch.Venkat Ramana Niranjan Ramchandra Thote arun kumar singh Visvesvaraya National Institute of Technology Nagpur440010India

The tension cracks and joints in rock or soil slopes affect their failure *** of rock or soil slope failure is one of the most challenging tasks in the earth *** actual slopes consist of inhomogeneous materials,complex morphology,and erratic *** studies concerning the failure of rock slopes primarily focused on determining Factor of Safety(FoS)and Critical Slip Surface(CSS).In this article,the effect of inclined tension crack on a rock slope failure is studied numerically with Shear Strength Reduction Factor(SRF)*** inclined Tension Crack(TC)inﬂuences the magnitude and location of the rock slope’s Critical Shear Strength Reduction Factor(CSRF).Certainly,inclined cracks are more prone to cause the failure of the slope than the vertical ***,all tension cracks do not lead to failure of the slope *** effect of the crest distance of the tension crack is also *** numerical results do not show any signiﬁcant change in the magnitude of CSRF unless the tip of the TC is very near to the crest of the *** is also replaced with a joint,and the results differ from the corresponding *** results are discussed regarding shear stress and Critical Slip Surface(CSS).

关键词： Crest distance critical shear strength reduction factor critical slip surface inclined tension crack joint

Effect of Heat Source/Sink on Free Convective Flow of a Polar Fluid between Vertical Concentric Annuli

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Journal of Applied Mathematics and Physics 2017年第9期5卷 1750-1762页

作者： arun kumar singh Ashok kumar singh Department of Mathematics Institute of Science Banaras Hindu University Varanasi India

The purpose of this paper is to find the effect of heat source/sink parameter on free convective flow of a polar fluid in open-ended vertical concentric annuli. Exact solutions of the non-dimensional differential equations describing the flow model have been obtained one by one for two different cases of source and sink. To observe the effect of the physical parameters such as source/sink and vertex viscosity, the numerical results of the velocity and microrotational velocity are finally shown on the graphs.

关键词： Polar Fluid Free Convection Isothermal and Constant Heat Flux Cases Temperature Dependent Heat Source/Sink Vertical Annuli

Robust Optimal H_∞ Control for Uncertain 2-D Discrete State-Delayed Systems Described by the General Model

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Journal of Signal and Information Processing 2016年第2期7卷 78-114页

作者： arun kumar singh Amit Dhawan Department of Electronics and Communication Engineering Motilal Nehru National Institute of Technology Allahabad India

This paper investigates the problem of robust optimal H∞ control for uncertain two-dimensional (2-D) discrete state-delayed systems described by the general model (GM) with norm-bounded uncertainties. A sufficient condition for the existence of g-suboptimal robust H∞ state feedback controllers is established, based on linear matrix inequality (LMI) approach. Moreover, a convex optimization problem is developed to design a robust optimal state feedback controller which minimizes the H∞ noise attenuation level of the resulting closed-loop system. Finally, two illustrative examples are given to demonstrate the effectiveness of the proposed method.

关键词： 2-D Discrete Systems General Model H∞ Control Linear Matrix Inequality State Feedback Uncertain System

Transient Stability Improvement of Power System Using Non-Linear Controllers

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Energy and Power Engineering 2014年第1期6卷 10-16页

作者： Rekha Chaudhary arun kumar singh Electrical Engineering Department NIT Jamshedpur Jamshedpur India

This paper presents the design of a non-linear controller to prevent an electric power system losing synchronism after a large sudden fault and to achieve good post fault voltage level. By Direct Feedback Linearization (DFL) technique robust non-linear excitation controller is designed which will achieve stability enhancement and voltage regulation of power system. By utilizing this technique, there is a possibility of selecting various control loops for a particular application problem. This method plays an important role in control system and power system engineering problem where all relevant variables cannot be directly measured. Simulated results carried out on a single machine infinite bus power system model which shows the enhancement of transient stability regardless of the fault and changes in network parameters.

关键词： Single Machine Infinite Bus (SMIB) Direct Feedback Linearization (DFL) Fuzzy Logic Controller (FLC) Sliding Mode Control (SMC)

Clodronate-superparamagnetic iron oxide-containing liposomes attenuate renal injury in rats with severe acute pancreatitis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2014年第6期15卷 556-565页

作者： Sheng-chun DANG Yan-hua ZENG Ping-jiang WANG Bao-ding CHEN Rong-fang CHEN arun kumar singh Pankaj kumar Shu FENG Lei CUI Hao WANG Jian-xin ZHANG Department of General Surgery the Affiliated Hospital of Jiangsu University

Background and objective： It has been shown that macrophages play an important role in the development of severe acute pancreatitis （SAP）, and eventually lead to multiple organ failure （MOF）. Clodronate-liposome selectively depleted macrophages. This study was to investigate the role of renal macrophage infiltration in acute renal injury in rats with SAP and to evaluate the potential of superparamagnetic iron oxide （SPIO）-enhanced magnetic resonance imaging （MRI） for diagnosis. Methods： Superparamagnetic Fe3O4 nanoparticles were prepared by chemical coprecipitation. SPIO-liposomes and SPIO-clodronate-liposomes were prepared by the thin film method. SAP models were prepared by injection of sodium taurocholate into the subcapsular space of rat pancreas. Sprague-Dawley rats were randomly divided into a control group, SAP plus SPIO-liposome （P） group, and SAP plus SPIO-clodronatecontaining liposome （T） group. Kidney injury was evaluated by T2-weighted MRI scan. The levels of serum amylase （SAM）, blood urea nitrogen （BUN）, and serum creatinine （SCr） were measured by an automated enzymatic method. Serum tumor necrosis factor-α （TNF-α） was measured by enzyme-linked immunosorbent assay （ELISA）. Pathological changes in the pancreas and kidney were observed using hematoxylin and eosin （H＆E） staining, while cell apoptosis was detected with terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） staining. In addition, the macrophage markers （CD68） of the renal tissue were detected with immunohistochemistry. Results： The pathological changes in the pancreas and kidneys of rats in the T group were milder than those in the P group. The MRI signal intensity of the kidneys in the P and T groups was significantly lower than that in the control group. There were significant changes in the two experimental groups （P〈0.01）. The levels of SAM, Bun, SCr, and TNF-α in rats in the P group were higher than those in the control group （P〈0.01） and in the T group （P〈0.01）. The apop

关键词： Pancreatitis Clodronate disodium Macrophage Kidney injury