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Frontiers of Architectural Research 2020年第3期9卷 697-710页

作者： Naadir Vorajee Asit Kumar mishra Amit Kumar mishra Electrical Engineering Department University of Cape TownCape Town 7700South Africa Berkeley Education Alliance for Research in Singapore CREATE Tower138602Singapore

Prohibitive equipment cost and certain export regulations are the major obstacles to the widespread adoption of infrared(IR)thermography when evaluating building *** this work,we propose the use of an affordable and easily available camera as a first step of making the technology *** with image post-processing,we hypothesize that a low-cost,low-resolution,and consumer-grade device can provide an economic alternative for the periodic evaluation of building *** a market survey,the Seek Thermal Compact(STC)was chosen for *** STC was able to accurately measure the temperature of surfaces and distinguish small thermal anomalies(3 mm in diameter),and the IR images can be post-processed to reasonably estimate the anomaly *** STC was particularly effective when images were taken within 1.75 m from the *** 1.75 m distance did not pose a challenge in this study,as the goal was to mount the selected IR camera on an unmanned aerial vehicle for the *** small size and weight of the STC were also *** results from the analysis of the capability of the STC and the image post-processing techniques may help form the basis of future investigations aiming at lowering the cost of building thermographic surveys.

关键词： IR thermography Building enve'opes Cost-effective Thermal images Image processing Segmentation algorithms

Adaptive Three-phase Estimation of Sequence Components and Frequency Using H∞ Filter Based on Sparse Model

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Journal of Modern Power Systems and Clean Energy 2020年第5期8卷 981-990页

作者： Umamani Subudhi Harish Kumar Sahoo Sanjeev Kumar mishra Department of Electronics and Telecommunication Engineering Indian Institute of Information Technology(IIIT)BhubaneshwarIndia Department of Electronics and Telecommunication Engineering Veer Surendra Sai University of Tecnology(Burla)SambalpurIndia

The estimation of sequence or symmetrical components and frequency in three-phase unbalanced power system is of great importance for protection and *** paper proposes a new H∞filter based on sparse model to track the sequence components and the frequency of three-phase unbalanced power *** inclusion of sparsity improves the error convergence behavior of estimation model and hence short-duration non-stationary PQ events can easily be tracked in the time *** proposed model is developed using l1 norm penalty in the cost function of H∞filter,which is quite suitable for estimation across all the three phases of an unbalanced *** model uses real state space modeling across three phases to estimate amplitude and phase parameters of sequence ***,frequency estimation uses complex state space modeling and Clarke transformation generates a complex measurement signal from the unbalanced three-phase *** state vector used for frequency estimation consists of two state *** proposed sparse model is tested using distorted three-phase signals from IEEE-1159-PQE database and the data generated from experimental laboratory *** analysis of absolute and mean square error is presented to validate the performance of the proposed model.

关键词： Sequence component Clarke transformation H∞filter state space model

Geochemical signatures of Mesoproterozoic siliciclastic rocks of the Kaimur Group of the Vindhyan Supergroup,Central India

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Chinese Journal Of Geochemistry 2010年第1期29卷 21-32页

作者： Meenal mishra Shinjana Sen Department of Geology Faculty of ScienceBanaras Hindu University

The Upper Kaimur Group of the Vindhyan Supergroup in Central India,primarily consists of three rock types-DhandraulSandstone,Scarp Sandstone and Bijaigarh *** and geochemically,they are quartz arenite,sublitharenite to litharenite and litharenite to shale in composition,*** A-CN-K ternary plot and CIA and ICV values suggest that the similar source rocks suffered severe chemical weathering,under a hot-humid climate in an acidic environment with higher PCO2,which facilitated high sediment influx in the absence of land *** geochemical discriminants,elemental ratios like K2O/Na2O,Al2O3/TiO2,SiO2/MgO,La/Sc,Th/Sc,Th/Cr,GdN/YbN and pronounced negative Eu anomalies indicate the rocks to be of post-Archean Proterozoic granitic source,with a minor contribution of granodioritic input,in a passive margin *** sediments of the Upper Kaimur Group were probably deposited in the interglacial period in between the Paleoproterozoic and Neoproterozoic glacial epochs.

关键词：地球化学特征中元古代印度 Al2O3/TiO2 碎屑岩超群二氧化碳分压地球化学判别

Physics-informed transient stability assessment of microgrids

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iEnergy 2023年第3期2卷 231-239页

作者： Priyanka mishra Peng Zhang Department of Electrical and Computer Engineering Stony Brook UniversityNY 11794USA

With the integration of a voltage source converter(VSC),having variable internal voltages and source impedance,in a microgrid with high resistance to reactance ratio of short lines,angle-based transient stability techniques may find *** such a situation,the Lyapunov function can be a viable option for transient stability assessment(TSA)of such a VSC-interfaced ***,the determination of the Lyapunov function with the classical method is very challenging for a microgrid with converter controller *** overcome such challenges,this paper develops a physics-informed,Lyapunov function-based TSA framework for VSC-interfaced *** method uses the physics involved and the initial and boundary conditions of the system in learning the Lyapunov *** method is tested and validated under faults,droop-coefficient changes,generator outages,and load shedding on a small grid-connected microgrid and the CIGRE microgrid.

关键词： Physics-informed neural network Lyapunov function voltage source converter transient stability assessment microgrid

Measurement Sensitivity and Estimation Error in Distribution System State Estimation using Augmented Complex Kalman Filter

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Journal of Modern Power Systems and Clean Energy 2020年第4期8卷 657-668页

作者： Alan Louis Gerard Ledwich Geoff Walker Yateendra mishra IEEE Queensland University of Technology BrisbaneAustralia

Distribution state estimation(DSE)is an essential part of an active distribution network with high level of distributed energy *** challenges of accurate DSE with limited measurement data is a well-known *** practice,the operation and usability of DSE depend on not only the estimation accuracy but also the ability to predict error *** paper investigates the application of error covariance in DSE by using the augmented complex Kalman filter(ACKF).The Kalman filter method inherently provides state error covariance *** can be utilized to accurately infer the error covariance of other parameters and provide a method to determine optimal measurement locations based on the sensitivity of error covariance to measurement noise *** paper also proposes a generalized formulation of ACKF to allow scalar measurements to be incorporated into the complex-valued *** proposed method is simulated by using modified IEEE 34-bus and IEEE 123-bus test feeders,and randomly generates the load data of complex-valued Wiener *** ACKF method is compared with an equivalent formulation using the traditional weighted least squares(WLS)method and iterated extended Kalman filter(IEKF)method,which shows improved accuracy and computation performance.

关键词： Augmented complex Kalman filter direct load flow distribution system state estimation error variance sensitivity analysis

Natural compounds as potential inhibitors of SARS-CoV-2 main protease: An insilico study

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Asian Pacific Journal of Tropical Biomedicine 2021年第4期11卷 155-163页

作者： Amaresh mishra Yamini Pathak Anuj Kumar Surabhi Kirti mishra Vishwas Tripathi School of Biotechnology Gautam Buddha UniversityGreater Noida-201310India Bioinformatics Laboratory Uttarakhand Council for BiotechnologyBiotech BhawanPantnagarU.S.NagarUttarakhand-263145India Advanced Centre for Computational and Applied Biotechnology Uttarakhand Council for BiotechnologyDehradun-248007India School of Biotechnology Jawaharlal Nehru UniversityNew DelhiIndia

Objective:To explore natural compounds as potential inhibitors against main protease(Mpro)of ***:In the current study,systematic molecular docking analysis was conducted using AutoDock 4.2 to determine the binding affinities and interactions between natural compounds and *** natural compounds were further validated using a combination of molecular dynamic(MD)simulations and molecular mechanic Poisson-Boltzmann surface area(MM/PBSA)free energy c alculation ***:Out of twenty natural compounds,four natural metabolites namely,amentoflavone,guggulsterone,puerarin,and piperine were found to have strong interaction with Mpro of SARS-CoV-2 based on docking *** MD simulations,all four natural compounds bound to Mpro at 50 ns and MM/G/P/BSA free energy calculations showed that all four shortlisted ligands had stable and favorable energies with strong binding to Mpro ***:Guggulsterone is a potential inhibitor of COVID-19 main protease *** in vitro and pre-clinical studies are needed.

关键词： SARS-CoV-2 COVID-19 Amentoflavone Guggulsterone Puerarin Piperine

Constraint Preserving Schemes Using Potential-Based Fluxes *** Transport Equations

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Communications in Computational Physics 2011年第3期9卷 688-710页

作者： Siddhartha mishra Eitan Tadmor Centre of Mathematics for Applications(CMA) University of OsloP.O.Box 1053BlindernN-0316 OsloNorway Center of Scientific Computation and Mathematical Modeling(CSCAMM) and Department of Mathematicsand Institute for Physical Sciences and Technology(IPST)University of MarylandMD 20742-4015USA

We consider constraint preserving multidimensional evolution equations.A prototypical example is provided by the magnetic induction equation of plasma *** constraint of interest is the divergence of the magnetic *** design finite volume schemes which approximate these equations in a stable manner and preserve a discrete version of the *** schemes are based on reformulating standard edge centered finite volume fluxes in terms of vertex centered *** potential-based approach provides a general framework for faithful discretizations of constraint transport and we apply it to both divergence preserving as well as curl preserving *** present benchmark numerical tests which confirm that our potential-based schemes achieve high resolution,while being constraint preserving.

关键词： Multidimensional evolution equations magnetohydrodynamics finite-difference finite volume schemes constraint transport potential-based schemes

Fine structural description of the compound eye of the Madagascar ＇hissing cockroach＇ Gromphadorhinaportentosa （Dictyoptera： Blaberidae）

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Insect Science 2008年第2期15卷 179-192页

作者： Monalisa mishra Victor Benno Meyer-Rochow Faculty of Engineering and Sciences Jacobs University (formerly known as International University Bremen) Bremen Germany Department of Biology (Elainmuseo) University of Oulu Oulu Finland

The compound eyes of the wingless adults of the Madagascar ＇hissing cockroach＇ Gromphadorhinaportentosa Sachum, 1853 were examined by light and electron microscopy. Each eye contains 2 400-2 500 mostly hexagonal facets. However, irregularities affecting both shape and size of the ommatidia are relatively common, especially towards the margins of the eye. An individual ommatidium of this eucone type of apposition eye contains eight retinula cells, which give rise to a centrally-fused, tiered rhabdom. The distal end of the latter is funnel-shaped and accommodates the proximal end of the cone in its midst, Further below, the rhabdom （then formed by the rhabdomeres of four retinula cells） assumes a squarish profile with microvilli aligned in two directions at right-angle to each other. Cross sections through the proximal regions of the rhabdom display triangular rhabdom outlines and microvilli （belonging to 3-4 retinula cells different from those involved in the squarish more distal rhabdom） that run in three directions inclined to one another by 120°. Overall the organization of the eye conforms to the orthopteroid pattern and particularly closely resembles that of the American cockroach Periplaneta americana. However, since G. portentosa possesses fewer ommatidia, this could be a consequence of its inability to fly. On the other hand, the large size of the facets and the voluminous rhabdoms suggest considerable absolute sensitivity and an ability to detect the plane of linearly polarized light. Based on the pattern of microvillus orientations in combination with the crepuscular lifestyle G. portentosa leads and the habitat it occurs in, the prediction is made that this insect uses its green receptors for e-vector discrimination in the environment of down-welling light that reaches the forest floor.

关键词： apposition blattodea closed rhabdom ommatidium polarization vision

Modelling of Wideband Concentric Ring Frequency Selective Surface for 5G Devices

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Computers, Materials & Continua 2023年第1期74卷 341-361页

作者： Ankush Kapoor Pradeep Kumar Ranjan mishra Department of Electronics and Communication Engineering Jawaharlal Nehru Government Engineering CollegeSundernagar175018India Discipline of Electrical Electronic and Computer EngineeringUniversity of KwaZulu-NatalDurban4041South Africa Department of Electrical and Electronics Engineering University of Petroleum and Energy StudiesDehradun248007India

Frequency selective surfaces(FSSs)play an important role in wireless systems as these can be used as filters,in isolating the unwanted radiation,in microstrip patch antennas for improving the performance of these antennas and in other 5G *** analysis and design of the double concentric ring frequency selective surface(DCRFSS)is presented in this *** the sub-6 GHz 5G FR1 spectrum,a computational synthesis technique for creating DCRFSS based spatial filters is *** analytical tools presented in this study can be used to gain a better understanding of filtering processes and for constructing the spatial *** of the loop sizes,angles of incidence,and polarization of the concentric rings are the factors which influence the transmission coefficient as per the thorough investigation performed in this paper.A novel synthesis approach based on mathematical equations that may be used to determine the physical parameters ofDCRFSSbased spatial filters is *** proposed synthesis technique is validated by comparing results from high frequency structure simulator(HFSS),Ansys electronic desktop circuit editor,and an experimental ***,the findings acquired from a unit cell are expanded to a 2×2 array,which shows identical performance and therefore proves its stability.

关键词： Spatial filters double concentric ring frequency selective surface(DCRFSS) angle of incidence finite element method(FEM) polarization angles

KINETIC FUNCTIONS IN MAGNETOHYDRODYNAMICS WITH RESISTIVITY AND HALL EFFECT

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Acta Mathematica Scientia 2009年第6期29卷 1684-1702页

作者： Philippe G. Le Siddhartha mishra FlochLaboratoire Jacques-Louis Lions Centre National de la Recherche ScientifiqueUniversit Pierre et Marie Curie (Paris 6) 4 Place Jussieu 75258 Paris France Seminar for Applied Mathematics D-Math ETH HG Raemistrasse Zürich-8092 Switzerland

We consider a nonlinear hyperbolic system of two conservation laws which arises in ideal magnetohydrodynamics and includes second-order terms accounting for magnetic resistivity and Hall effect. We show that the initial value problem for this model may lead to solutions exhibiting complex wave structures, including undercompressive nonclassical shock waves. We investigate numerically the subtle competition that takes place between the hyperbolic, diffusive, and dispersive parts of the system. Following Abeyratne, Knowles, LeFloch, and Truskinovsky, who studied similar questions arising in fluid and solid flows, we determine the associated kinetic function which characterizes the dynamics of undereompressive shocks driven by resistivity and Hall effect. To this end, we design a new class of ＂schemes with eontroled dissipation＂, following recent work by LeFloch and Mohammadian. It is now recognized that the equivalent equation associated with a scheme provides a guideline to design schemes that capture physically relevant, nonclassical shocks. We propose a new class of schemes based on high-order entropy conservative, finite differences for the hyperbolic flux, and high-order central differences for the resistivity and Hall terms. These schemes are tested for several regimes of （co-planar or not） initial data and parameter values, and allow us to analyze the properties of nonclassical shocks and establish the existence of monotone kinetic functions in magnetohydrodynamics.

关键词： hyperbolic conservation law magnetohydrodynamics magnetic resistivity Hall effect undercompressive shock kinetic function