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Bending analysis of five-layer curved functionally graded sandwich panel in magnetic field:closed-form solution

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Applied Mathematics and Mechanics(English Edition) 2021年第2期42卷 251-274页

作者： M.shaban h.MAZAhERI Mechanical Engineering Department Bu-Ali Sina UniversityHamadan 3869-6517Iran

In this paper,an exact closed-form solution for a curved sandwich panel with two piezoelectric layers as actuator and sensor that are inserted in the top and bottom facings is *** core is made from functionally graded(FG)material that has heterogeneous power-law distribution through the radial *** is assumed that the core is subjected to a magnetic field whereas the core is covered by two insulated composite *** determine the exact solution,first characteristic equations are derived for different material types in a polar coordinate system,namely,magneto-elastic,elastic,and electro-elastic for the FG,orthotropic,and piezoelectric materials,*** displacement-based method is used instead of the stress-based method to derive a set of closed-form real-valued solutions for both real and complex *** on the elasticity theory,exact solutions for the governing equations are determined layer-by-layer that are considerably more accurate than typical simplified *** accuracy of the presented method is compared and validated with the available literature and the finite element *** effects of geometrical and material parameters such as FG index,angular span along with external conditions such as magnetic field,mechanical pressure,and electrical difference are investigated in detail through numerical examples.

关键词： five-layer sandwich panel piezoelectric material closed-form solution functionally graded(FG)material magnetic field

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-tALOOKOLAEI h.GhANDVAR E.JUMAEV S.KhAtIR t.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and technology Solutions Ho Chi Minh City Open University

this paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. the strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. the curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. the accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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Denoising different types of acoustic partial discharge signals using power spectral subtraction

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high Voltage 2018年第1期3卷 44-50页

作者： Ramy hussein Khaled Bashir shaban Ayman h.El-hag Department of Electrical and Computer Engineering University of British ColumbiaVancouverBCCanada Department of Computer Science and Engineering Qatar UniversityDohaQatar Department of Electrical Engineering American University of SharjahSharjahUAE

Measuring acoustic emission(AE)of partial discharge(PD)phenomena can be adopted to estimate the condition of power ***,the environmental noise encountered with AE of PD measurements negatively affects the accuracy of PD localisation and ***,efficient signal denoising techniques are required for noise suppression and hence,better detection *** study deals with white noise and it is a continuation of a previously published work that deals with random *** published work addresses the random noise suppression using a method named,power spectral subtraction denoising(PSSD).this study applies PSSD to the PD signals contaminated with white noise and uses a novel scheme of noise power spectrum density *** types of AE signals are examined including signals produced by corona,surface,parallel,and void *** and real data demonstrate the superiority of the proposed method over the wavelet shrinkage denoising method as it can more effectively eliminate white noise and preserve signals of low signal-to-noise ratio.

关键词： power noise spectral

Leveraging ROtI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia

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Earth and Planetary Physics 2025年第1期9卷 101-116页

作者： Prayitno Abadi Ihsan N.Muafiry teguh N.Pratama Angga Y.Putra Suraina Gatot h.Pramono Sidik t.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.tresna Asnawi Research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory Management Facilities and Science and technology Park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia Geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia Research Center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia Research Center for Photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and Planetary Sciences Hokkaido UniversitySapporoJapan

this paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning *** by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude ***-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EPB research,by sharing two-dimensional rate of total Electron Content(tEC)change index(ROtI)derived from this *** generate ROtI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific *** preliminary findings from the ROtI maps of Ina-CORS are ***,the Ina-CORS ROtI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined ROtI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined ROtI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing ROtI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of tEC change index(ROtI)map

Determination of trap density-of-states distribution of nitrogen-doped ultrananocrystalline diamond/hydrogenated amorphous carbon composite films

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Journal of Semiconductors 2021年第6期42卷 48-54页

作者： Mahmoud shaban Department of Electrical Engineering College of EngineeringQassim UniversityUnaizah 56452Saudi Arabia Department of Electrical Engineering Faculty of EngineeringAswan UniversityAswan 81542Egypt

thin films comprising nitrogen-doped ultrananocrystalline diamond/hydrogenated amorphous-carbon(UNCD/a-C:h)composite films were experimentally *** prepared films were grown on Si substrates by the coaxial arc plasma deposition *** were characterized by temperature-dependent capacitance-frequency measurements in the temperature and frequency ranges of 300-400 K and 50 khz-2 Mhz,*** energy distribution of trap density of states in the films was extracted using a simple technique utilizing the measured capacitance-frequency *** the measured temperature range,the energy-distributed traps exhibited Gaussian-distributed states with peak values lie in the range:2.84×10^(16)-2.73×10^(17)eV^(-1)cm^(-3)and centered at energies of 120-233 meV below the conduction *** states are generated due to a large amount of sp^(2)-C andπ-bond states,localized in GBs of the UNCD/a-C:h *** attained defect parameters are accommodating to understand basic electrical properties of UNCD/a-C:h composite and can be adopted to suppress defects in the UNCD-based materials.

关键词： nitrogen-doping nanodiamond UNCD/a-C:h capacitance-frequency characterization trap density-of-states

Solution for Energies and Mixing of two 0^+ States in ^(10)he

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Chinese Physics Letters 2016年第9期33卷 27-28页

作者： h.t.Fortune Department of Physics and Astronomy University of Pennsylvania

Using results from various reactions that populate 10he, I conclude that the ground state has E2n = 1.07（7） MeV and the excited 0＋ state is in the region of 2.1-3.1 MeV. the amount of the （sd）2 component in the g... 详细信息

关键词： of is on for that Solution for Energies and Mixing of two 0 States in he

Peristaltic flow of Johnson-Segalman fluid in asymmetric channel with convective boundary conditions

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Applied Mathematics and Mechanics(English Edition) 2014年第6期35卷 697-716页

作者： h.YASMIN t.hAYAt A.ALSAEDI h.h.ALSULAMI Department of Mathematics Quaid-i-Azam University Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Faculty of Science King Abdulaziz University

this work is concerned with the peristaltic transport of the Johnson-Segalman fluid in an asymmetric channel with convective boundary conditions. the mathematical modeling is based upon the conservation laws of mass, linear momentum, and energy. the resulting equations are solved after long wavelength and low Reynolds number are used. the results for the axial pressure gradient, velocity, and temperature profiles are obtained for small Weissenberg number. the expressions of the pressure gra-dient, velocity, and temperature are analyzed for various embedded parameters. Pumping and trapping phenomena are also explored.

关键词： asymmetric channel convective condition pumping and trapping Johnson-Segalman fluid

Numerical simulation of triaxial compression test for brittle rock sample using a modified constitutive law considering degradation and dilation behavior

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Journal of Central South University 2015年第8期22卷 3097-3107页

作者：谭鑫 KONIEtZKY h FRühWIRt t College of Civil Engineering Hunan University Geotechnical Institute TU Bergakademie Freiberg

the understanding of the rock deformation and failure process and the development of appropriate constitutive models are the basis for solving problems in rock engineering. In order to investigate progressive failure behavior in brittle rocks, a modified constitutive model was developed which follows the principles of the continuum damage mechanics method. It incorporates non-linear hoek-Brown failure criterion, confining pressure-dependent strength degradation and volume dilation laws, and is able to represent the nonlinear degradation and dilation behaviors of brittle rocks in the post-failure region. A series of triaxial compression tests were carried out on Eibenstock(Germany) granite samples. Based on a lab data fitting procedure, a consistent parameter set for the modified constitutive model was deduced and implemented into the numerical code FLAC3 D. the good agreement between numerical and laboratory results indicates that the modified constitutive law is well suited to represent the nonlinear mechanical behavior of brittle rock especially in the post-failure region.

关键词： progress failure strength degradation dilation hoek-Brown criterion numerical simulation brittle rock

transport Properties of AgInSe<sub>2</sub>Crystals

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Materials Sciences and Applications 2014年第5期5卷 292-299页

作者： hamdy t. shaban Melaad K. Gergs Physics Department College of Science and Arts Najran University Najran KSA Physics Department Faculty of Science South Valley University Qena Egypt Physics Department Faculty of Science South Valley University Qena Egypt

AgInSe2 crystals were grown by Bridgman technique. the crystals were identified structurally by X-ray diffraction technique. Measurements of electrical conductivity and hall effect were performed in the temperature range (138 K - 434 K) and (220 K - 488 K) for thermoelectric power measurements. From these measurements, many physical parameters were determined. the energy gap was calculated to be 1.24 eV. the conductivity type was found to be n-type. Crystallite size (D) of the obtained AgInSe2 crystals was calculated to be 70 nm. the lattice parameters for the prepared crystals were a = 6.0938 ? and c = 11.7775 ?.

关键词： Semiconductors Crystal Growth X-Ray Diffraction transport Properties