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PDE Constrained Optimization and Design of Frozen Mode Crystals

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Communications in Computational Physics 2008年第4期3卷 878-898页

作者： s.Chun j.s.Hesthaven Division of Applied Mathematics Brown UniversityProvidenceRI 02912USA.

We explore the use of PDE constrained nonlinear optimization techniques to optimize and design electromagnetic crystals which exhibit frozen mode *** is characterized by Van Hove singularities in the dispersion relation,e.g.,stationary reflection points and degenerate band edge ***,the optimization process modifies the dispersion relation by adjusting the geometries and material *** resulting algorithm is found to be capable of recovering all known crystal configurations as well as many new configurations,some of which display dramatically improved properties over previously used *** investigate both gyrotropic photonic crystals and degenerate band edge crystals as well as the more complex case of the oblique *** this latter case,we extend the investigation to the three-dimensional case to identify the first three-dimensional crystal exhibiting frozen mode behavior.

关键词： PDE constrained optimization method of matched asymptotics frozen mode photonic crystal.

swampland ds conjecture in mimetic f(R,T)gravity

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Communications in Theoretical Physics 2022年第8期74卷 101-115页

作者： s Noori Gashti j sadeghi s Upadhyay M R Alipour Department of Physics Faculty of Basic SciencesUniversity of Mazandaran PO Box 47416-95447BabolsarIran Department of Physics K.L.S.CollegeNawadaBihar 805110India Department of Physics Magadh UniversityBodh GayaBihar 824234India Inter-University Centre for Astronomy and Astrophysics(IUCAA) PuneMaharashtra 411007India school of Physics Damghan UniversityDamghan ***Iran

In this paper,we study a theory of gravity called mimetic f(R,T)in the presence of swampland ds *** this purpose,we introduce several inflation solutions of the Hubble parameter H(N)from f(R,T)=R+δT gravity model,in which R is Ricci scalar,and T denotes the trace of the energy–momentum ***,δand N are the free parameter and a number of e-fold,*** we calculate quantities such as potential,Lagrange multiplier,slow-roll,and some cosmological parameters such as nsand *** we challenge the mentioned inflationary model from the swampland ds *** discuss the stability of the model and investigate the compatibility or incompatibility of this inflationary scenario with the latest Planck observable data.

关键词： mimetic f(R,T)gravity Lagrange multiplier swampland conjecture

A Novel Training Algorithm of Genetic Neural Networks and Its Application to Classification

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journal of systems Engineering and Electronics 2001年第3期12卷 76-84页

作者： Xiao, j. Wu, j. Yang, s. school of Mechanics Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

First of all, this paper discusses the drawbacks of multilayer perceptron (MLP), which is trained by the traditional back propagation (BP) algorithm and used in a special classification problem. A new training algorithm for neural networks based on genetic algorithm and BP algorithm is developed. The difference between the new training algorithm and BP algorithm in the ability of nonlinear approaching is expressed through an example, and the application foreground is illustrated by an example.

关键词： Backpropagation Computer simulation Genetic algorithms Mathematical models Nonlinear control systems Problem solving

Energy-Efficient Routing Protocol with Multi-Hop Fuzzy Logic for Wireless Networks

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Intelligent Automation & soft Computing 2023年第5期36卷 2457-2471页

作者： j.Gobinath s.Hemajothi j.s.Leena jasmine Department of Information and Communication Engineering Anna UniversityChennai600025India Department of Electronics and Communication Engineering Vel Tech High Tech Dr.Rangarajan Dr.Sakunthala Engineering CollegeChennai600062India Department of Computer science and Engineering Velammal Engineering CollegeChennai600066India

A Wireless sensor Network(WsN)becomes a newer type of real-time embedded device that can be utilized for a wide range of applications that make regular networking which appears *** the energy produc-tion of the nodes,WsN has major issues that may inﬂuence the stability of the *** a result,constructing WsN requires devising protocols and standards that make the most use of constrained capacity,especially the energy *** faces some issues with increased power utilization and an on going devel-opment due to the uneven energy usage between the *** has proven to be a more effective strategy in this *** the proposed work,a hybrid meth-od is used for reducing the energy consumption among CHs.A Fuzzy Logic-based clustering protocol FLUC(unequally clustered)and Fuzzy Clustering with Energy-Efﬁcient Routing Protocol(FCERP)are used.A Fuzzy Clustering with Energy Efﬁcient Routing Protocol(FCERP)reduces the WsN power usage and increases the lifespan of the *** has created a novel cluster-based fuzzy routing mechanism that uses a limit value to combine the clustering and multi-hop routing *** technique creates uneven groups by using fuz-zy logic with a competitive range to choose the Cluster Head(CH).The input variables include the distance of the nodes from the ground station,concentra-tions,and remaining *** proposed FLUC-FCERP reduces the power usage and improves the lifetime of the network compared with the existing algorithms.

关键词： Energy consumption lifetime wireless sensor network cluster head fuzzy logic unequally clustered fuzzy clustering energy-efﬁcient protocol

Modeling of the Frozen Mode Phenomenon and its sensitivity Using Discontinuous Galerkin Methods

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Communications in Computational Physics 2007年第4期2卷 611-639页

作者： s.Chun j.s.Hesthaven Division of Applied Mathematics Brown UniversityProvidenceRI 02912USA.

We investigate the behavior and sensitivity of the frozen mode phenomenon in finite structures with anisotropic materials,including both magnetic materials and non-normal *** studies are done by using a high-order accurate discontinuous Galerkin method for solving Maxwells equations in the time *** confirm the existence of the phenomenon also in the time-domain and study carefully the impact of the finite crystal on the frozen *** sets the stage for a thorough study of the robustness of the frozen mode phenomenon,resulting in guidelines for which design parameters are most sensitive and acceptable tolerances.

关键词： Discontinuous Galerkin method Maxwell equation photonic crystals frozen mode.

self-adjoint Extensions for the Neumann Laplacian and Applications

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Acta Mathematica sinica,English series 2006年第3期22卷 879-906页

作者： s.A.NAZAROV j.sOKOLOWsKI Institute of Mechanical Engineering Problems V.O.Bolshoy pr.61 199178 St Petersburg Russia Institut Elie Cartan Laboratoire de Mathématiques Université Henri Poincaré NancyI B.P.239 54506 Vandoeuvrelès Nancy Cedex France and systems Research Institute of the Polish Academy of sciences ul.Newelska601-447Warszawa Poland

A new technique is proposed for the analysis of shape optimization problems. The technique uses the asymptotic analysis of boundary value problems in singularly perturbed geometrical domains. The asymptotics of solutions are derived in the framework of compound and matched asymptotics expansions. The analysis involves the so-called interior topology variations. The asymptotic expansions are derived for a model problem, however the technique applies to general elliptic boundary value problems. The self-adjoint extensions of elliptic operators and the weighted spaces with detached asymptotics are exploited for the modelling of problems with small defects in geometrical domains, The error estimates for proposed approximations of shape functionals are provided.

关键词： shape optimization asymptotic expansions self-adjoint extension weighted spaces with detached asymptotics topological derivatives

Performanceanalysisofalowpowerlownoisetunablebandpassfilterformultiband RF front end

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journal of semiconductors 2014年第3期35卷 102-108页

作者： j.Manjula s.Malarvizhi Department of ECE SRM University

This paper presents a low power tunable active inductor and RF band pass filter suitable for multiband RF front end circuits. The active inductor circuit uses the PMOs cascode structure as the negative transconductor of a gyrator to reduce the noise voltage. Also, this structure provides possible negative resistance to reduce the inductor loss with wide inductive bandwidth and high resonance frequency. The RF band pass filter is realized using the proposed active inductor with suitable input and output buffer stages. The tuning of the center frequency for multiband operation is achieved through the controllable current source. The designed active inductor and RF band pass filter are simulated in 180 nm and 45 nm CMOs process using the synopsys HsPICE simulation tool and their performances are compared. The parameters, such as resonance frequency, tuning capability, noise and power dissipation, are analyzed for these CMOs technologies and discussed. The design of a third order band pass filter using an active inductor is also presented.

关键词： active inductor RF band pass filter quality factor center frequency tuning multi band RF front end 0.18 υm and 45 nm CMOs technology

Chemical reaction effects on unsteady MHD flow past semi-infinite vertical porous plate with viscous dissipation

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Applied Mathematics and Mechanics(English Edition) 2011年第8期32卷 1065-1078页

作者： j.A.RAO s.sHIVAIAH Department of Mathematics Osmania University Department of Mathematics Padmasri Dr.B.V.Raju Institute of Technology

The chemical reaction effect on an unsteady magnetohydrodynamic （MHD） flow past a semi-infinite vertical porous plate with viscous dissipation is analyzed. The governing equations of motion, energy, and species are transformed into ordinary differential equations （ODEs） using the time dependent similarity parameter. The resultant ODEs are then solved numerically by a finite element method. The effects of various parameters on the velocity, temperature, and concentration profiles are presented graphically, and the values of the skin-friction, Nusselt number, and sherwood number for various values of physical parameters are presented through tables.

关键词： magnetohydrodynamic (MHD) chemical reaction porous medium viscous dissipation finite element method

A Novel Forgery Detection in Image Frames of the Videos Using Enhanced Convolutional Neural Network in Face Images

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Computer Modeling in Engineering & sciences 2020年第11期125卷 625-645页

作者： s.Velliangiri j.Premalatha CMR Institute of Technology Hyderabad501401India Kongu Engineering College Erode638052India

Different devices in the recent era generated a vast amount of digital ***,it has been seen in recent years that people are forging the video to use it as proof of evidence in the court of *** kinds of researches on forensic detection have been presented,and it provides less *** paper proposed a novel forgery detection technique in image frames of the videos using enhanced Convolutional Neural Network(CNN).In the initial stage,the input video is taken as of the dataset and then converts the videos into image ***,perform pre-sampling using the Adaptive Rood Pattern search(ARPs)algorithm intended for reducing the useless *** the next stage,perform preprocessing for enhancing the image ***,face detection is done as of the image utilizing the Viola-jones ***,the improved Crow search Algorithm(ICsA)has been used to select the extorted features and inputted to the Enhanced Convolutional Neural Network(ECNN)classifier for detecting the forged image *** experimental outcome of the proposed system has achieved 97.21%accuracy compared to other existing methods.

关键词： Adaptive Rood Pattern search(ARPs) Improved Crow search Algorithm(ICsA) Enhanced Convolutional Neural Network(ECNN) Viola jones algorithm speeded Up Robust Feature(sURF)