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Defence Technology（防务技术） 2021年第6期17卷 1918-1935页

作者： naveen Kumar H s subhaschandra Kattimani Tnguyen-Thoi Department of Mechanical Engineering National Institute of Technology KarnatakaSurathkal575025India Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Duc Thang UniversityHo Chi Minh CityViet Nam Faculty of Civil Engineering Ton Duc Thang University Ho Chi Minh CityViet Nam

This article deals with the investigation of the effects of porosity distributions on nonlinear free vibration and transient analysis of porous functionally graded skew(PFGs)*** effective material properties of the PFGs plates are obtained from the modified power-law equations in which gradation varies through the thickness of the PFGs plate.A nonlinear finite element(FE)formulation for the overall PFGs plate is derived by adopting first-order shear deformation theory(FsDT)in conjunction with von Karman’s nonlinear strain displacement *** governing equations of the PFGs plate are derived using the principle of virtual *** direct iterative method and newmark’s integration technique are espoused to solve nonlinear mathematical *** influences of the porosity distributions and porosity parameter indices on the nonlinear frequency responses of the PFGs plate for different skew angles are studied in various *** effects of volume fraction grading index and skew angle on the plate’s nonlinear dynamic responses for various porosity distributions are illustrated in detail.

关键词： Porous functionally graded skew plates Porosity distributions nonlinear transient response nonlinear frequency ratio nonlinear frequency parameter

China’s soft power and Us public opinion

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Economic and Political studies 2021年第4期9卷 447-460页

作者： Yao-Yuan Yeh Charles K.s.Wu Wei-hao Huang Department of International studies&Modern Languages University of St.ThomasHoustonTXUSA Department of Political science Purdue UniversityWest LafayetteINUSA Institute of Political science Sun Yat-sen UniversityKaohsiungTaiwanChina

In recent years,China has been using its soft power(most notably,the establishment of Confucius Institutes)to influence public opinion in foreign ***,the literature on soft power has yet to provide a definitive answer about whether that has led to a positive image of China in the foreign ***,it is not clear if a positive image would influence public attitudes concerning foreign policies in those countries,such as policies related to trade and military *** on an online survey experiment in June 2018,this research shows that soft power information(about positive contributions of Confucius Institutes to the American society)does make the Us public feel warmer towards China and become more willing to support trade ***,the warm feeling does not alter public attitudes towards a potential military conflict with China over disputed islands in the south China *** study provides both empirical support and advice to policymakers interested in the influence of China’s soft power on Us public opinion.

关键词： soft power hard power American public opinion China

nonlinear Dust Acoustic Waves in a Magnetized Dusty Plasma with Trapped and superthermal Electrons

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Plasma science and Technology 2014年第6期16卷 545-551页

作者： s.Ahmadi ABRIsHAMI M.nouri KADIJAnI Islamic Azad University Torbateheydarieh Branch Torbateheydarieh Young Researchers and Elite Club Kashmar Branch Islamic Azad University

In this work, the effects of superthermal and trapped electrons on the oblique propa- gation of nonlinear dust-acoustic waves in a magnetized dusty （complex） plasma are investigated. The dynamic of electrons is simulated by the generalized Lorentzian （k） distribution function （DF）. The dust grains are cold and their dynamics are simulated by hydrodynamic equations. Using the standard reductive perturbation technique （RPT） a nonlinear modified Korteweg-de Vries （mKdV） equation is derived. Two types of solitary waves; fast and slow dust acoustic solitons, exist in this plasma. Calculations reveal that compressive solitary structures are likely to propagate in this plasma where dust grains are negatively （or positively） charged. The properties of dust acoustic solitons （DAss） are also investigated numerically.

关键词： dust acoustic wave trapped electrons superthermal electrons kappa distribution function

Microwave assisted synthesis,spectroscopy and biochemical aspects of lanthanum(Ⅲ) and praseodymium(Ⅲ) complexes with oxadiazole functionalised dithiocarbazinates

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Journal of Rare Earths 2009年第5期27卷 698-704页

作者： shweta singh O P Pandey s K sengupta Department of Chemistry D.D.U.Gorakhpur University Chemistry Department University of Surrey

The new lanthanum (Ⅲ) and praseodymium (Ⅲ) complexes of the general formula [Ln(L)3] (Ln=La(Ⅲ) or Pr(Ⅲ); LK=potassium salt of dithiocarbazinates) were prepared by both, conventional thermal and by the use of microwave technology. Elemental analyses, electrical conductance, magnetic moment and electronic, infrared, far-infrared, 1H and 13C nMR spectral studies were used to characterize the complexes. The molecular weights of few complexes were determined by FAB-mass spectra. nephelauxetic ratio, covalency parameter and bonding parameter for these complexes were also calculated. The probable structures of the complexes were proposed. The antifungal and antibacterial activities of the complexes were evaluated. The activities were correlated with the structures of the compounds.

关键词： lanthanum (Ⅲ) praseodymium (Ⅲ) dithiocarbazinates microwave synthesis structures antifungal antibacterial rare earths

Characterization of ceramic reinforced titanium matrix composites fabricated by spark plasma sintering for anti-ballistic applications

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Defence Technology（防务技术） 2018年第5期14卷 408-411页

作者： s.W.Maseko A.P.I.Popoola O.s.I.Fayomi Department of Chemical Metallurgicaland Materials EngineeringTshwane University of TechnologyPretoriaSouth Africa Department of Mechanical Engineering Covenant UniversityOtaNigeria

Titanium has found extensive use in various engineering applications due to its attractive physical,mechanical, and chemical characteristics. However, titanium has relatively low hardness for use as an armour material. ZrB2 was incorporated to the Ti matrix to form a Ti-based binary composites. In this study, powder metallurgy techniques were employed to disperse the ceramic particulates throughout the matrix material then consolidated through spark plasma sintering. The composites were densified at1300 ℃, pressure of 50 MPa, and holding time of 5 min. The microstructure and phase analysis of the sintered composites was carried out using sEM and XRD, while the hardness was determined using Vickers' microhardness tester. The sEM and XRD results confirmed the presence of the TiB whiskers which renowned with the improving the hardness of titanium. The hardness of the composite with 10 wt% ZrB_2 showed the highest hardness compared to that obtained for the 5 and 15 wt% ZrB_2 composites which was 495 and 571 Hv respectively.

关键词： sPs TiB whiskers Hardness Titanium matrix composites Reinforcement

smart residential energy management system for demand response in buildings with energy storage devices

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Frontiers in Energy 2019年第4期13卷 715-730页

作者： s.L.ARUn M.P.sELVAn Hybrid Electrical systems Laboratory Department of Electrical and Electronics EngineeringNational Institute of TechnologyTiruchirappalli-620015India

In the present scenario,the utilities are focusing on smart grid technologies to achieve reliable and profitable grid *** side management(DsM)is one of such smart grid technologies which motivate end users to actively participate in the electricity market by providing *** are expected to respond(demand response(DR))in various ways to attain these ***,residential consumers are interested in energy storage devices such as battery to reduce power consumption from the utility during peak *** this paper,the use of a smart residential energy management system(sREMs)is demonstrated at the consumer premises to reduce the total electricity bill by optimally time scheduling the operation of household ***,the sREMs effectively utilizes the battery by scheduling the mode of operation of the battery(charging/floating/discharging)and the amount of power exchange from the battery while considering the variations in consumer demand and utility parameters such as electricity price and consumer consumption limit(CCL).The sREMs framework is implemented in Matlab and the case study results show significant yields for the end user.

关键词： smart grid demand side management(DsM) demand response(DR) smart building smart appliances energy storage

An Extrinsic Fiber Fabry-Perot Interferometer for Dynamic Displacement Measurement

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Photonic sensors 2015年第1期5卷 50-59页

作者： s. PULLTEAP H. C. sEAT Department of Mechanical Engineering Faculty of Engineering and Industrial Technology Silpakorn University(Sanam Chandra Palace Campus) Nakhon Pathom 73000 Thailand Optoelectronics for Embedded systems Group INPT-ENSEEIHT Rue Charles Camichel BP 7122-31071 Toulouse Cedex 7 France

A versatile fiber interferometer was proposed for high precision measurement. The sensor exploited a double-cavity within the unique sensing arm of an extrinsic-type fiber Fabry-Perot interferometer to produce the quadrature phase-shifted interference fringes. Interference signal processing was carried out using a modified zero-crossing （fringe） counting technique to demodulate two sets of fringes. The fiber interferometer has been successfully employed for dynamic displacement measurement under different displacement profiles over a range of 0.7 p.m to 140 p.m. A dedicated computer incorporating the demodulation algorithm was next used to interpret these detected data as well as plot the displacement information with a resolution of 2/64. A commercial displacement sensor was employed for comparison purposes with the experimental data obtained from the fiber interferometer as well as to gauge its performance, resulting in the maximum error of 2.8% over the entire displacement range studied.

关键词： Fabry-Perot interferometer vibration analysis fringe counting technique displacement profile

stability of triple diffusive convection in a viscoelastic fluid-saturated porous layer

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Applied Mathematics and Mechanics(English Edition) 2018年第10期39卷 1385-1410页

作者： K.R.RAGHUnATHA I.s.sHIVAKUMARA Department of Mathematics Bangalore University

The triple diffusive convection in an Oldroyd-B fluid-saturated porous layer is investigated by performing linear and weakly nonlinear stability analyses. The condition for the onset of stationary and oscillatory is derived analytically. Contrary to the observed phenomenon in newtonian fluids, the presence of viscoelasticity of the fluid is to degenerate the quasiperiodic bifurcation from the steady quiescent state. Under certain conditions, it is found that disconnected closed convex oscillatory neutral curves occur, indicating the requirement of three critical values of the thermal Darcy-Rayleigh number to identify the linear instability criteria instead of the usual single value, which is a novel result enunciated from the present study for an Oldroyd-B fluid saturating a porous medium. The similarities and differences of linear instability characteristics of Oldroyd-B, Maxwell, and newtonian fluids are also highlighted. The stability of oscillatory finite amplitude convection is discussed by deriving a cubic Landau equation,and the convective heat and mass transfer are analyzed for different values of physical parameters.

关键词： Oldroyd-B fluid bifurcation instability perturbation method nonlinear stability heat and mass transfer

Fuzzy Logic Based Power Flow Control Analysis of Advanced Unified Power Flow Controller

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Journal of Energy and Power Engineering 2011年第3期5卷 252-259页

作者： s.K. srivastava s.n. singh Department of Electrical Engineering MMM Engineering College Gorakhpur-273010 India Department of Electrical Engineering Indian Institute of Technology Kanpur-208016 India

Due to rapidly development of high power semiconductor devices with fast control features have made possible to control the power flow more efficiently and effectively. The Flexible AC Transmission systems （FACTs） in this category introduces several innovative operating control devices. One of the recent devices is Advanced Unified Power Flow Controller （AUPFC） or multi-converter UPFC, which can control bus voltage and real and reactive power flows of more than one line or even a sub-network. This paper presents performance analysis of AUPFC based on d-q axis model theory. Based on the analysis, a new fuzzy logic rules based control algorithm has been developed in this paper which improves the system performance. The control rules are structured depending upon the relationship between series inserted voltages in multi-line and the desired changes of real and reactive power flows in the control network. The impacts of different controllers along with parameters of series connected transformers and transmission lines have been investigated through developed control block models in sIMULInK. The effectiveness of the proposed scheme is demonstrated by a case study.

关键词： FACTs AUPFC multi-converter UPFC fuzzy-PI controller sIMULInK FLC.

Parametric Anisotropic(p,q)-neumann Problems

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应用数学学报:英文版 2023年第4期39卷 926-942页

作者： Zhen-hai LIU nikolaos s.PAPAGEORGIOU Center for Applied Mathematics of Guangxi Yulin Normal UniversityYulin 537000China Guangxi Key Laboratory of Universities Optimization Control and Engineering Calculation Guangxi Minzu UniversityNanning 530006China Department of Mathematics National Technical UniversityZografou Campus15780 AthensGreece

We consider a neumann problem driven by a(p(z), q(z))-Laplacian(anisotropic problem) plus a parametric potential term with λ > 0 being the parameter. The reaction is superlinear but need not satisfy the Ambrosetti-Rabinowitz condition. We prove a bifurcation-type theorem describing the changes in the set of positive solutions as the parameter λ moves on R_(+)=(0,+∞).

关键词： variable exponent spaces superlinear reaction bifurcation-type theorem anisotropic regularity strong comparison positive solutions