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Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 123-138页

作者： Chentong GAO Huiyu SUN Jianping GU W.m.HUANG College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics School of mechanical and Aerospace Engineering Nanyang Technological University Jiangsu key Laboratory of Advanced Structural materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology

Currently, there are a limited number of dynamic models available for braided composite plates with large overall motions, despite the incorporation of three-dimensional(3D) braided composites into rotating blade components. In this paper, a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established. Based on kirchhoff's plate assumptions, the displacement variables of the plate are expressed. By incorporating the braiding directions into the constitutive equation of the braided composites, the dynamic model of the plate considering braiding directions is obtained. The effects of the speeds, braiding directions, and braided angles on the responses of the plate with fixed-axis rotation and translational motion, respectively, are investigated. This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions. It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications.

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Simulation of the spatio-temporal evolution of the electron energy distribution function in a pulsed hollow-cathode discharge

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Plasma Science and Technology 2023年第3期25卷 87-94页

作者： N A ASHURBEkOV k O ImINOV k m RABADANOV G S SHAkHSINOV m Z ZAkARYAEVA m B kURBANGADZHIEVA Dagestan State University Department of Physics Harbin Institute of Technology Institute of Physics Dagestan Federal Research CenterRussian Academy of Sciences

This article presents the 2D simulation results of a nanosecond pulsed hollow cathode discharge obtained through a combination of fluid and kinetic *** spatio-temporal evolution of the electron energy distribution function(EEDF)of the plasma column and electrical characteristics of the nanosecond pulsed hollow cathode discharge at a gas pressure of 5 Torr are *** results show that the discharge development starts with the formation of an ionization front at the anode *** ionization front splits into two parts in the cathode cavity while propagating along its lateral *** ionization front formation leads to an increase in the fast isotropic EEDF component at its front,as well as in the anisotropic EEDF *** accelerated electrons enter the cathode cavity,which significantly contributes to the formation of the highenergy EEDF component and EEDF anisotropy.

关键词： pulsed nanosecond discharge electron energy distribution fuinction hollow cathode electron kinetics gas discharge

The dynamics of a nanosecond gas discharge development with an extended slot cathode in argon

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Plasma Science and Technology 2020年第12期22卷 78-88页

作者： N A ASHURBEkOV k O ImINOV G S SHAkHSINOV m Z ZAkARYAEVA k m RABADANOV Dagestan State University Faculty of PhysicsMakhachkala 367000Russia Institute of Physics DFRC of RASMakhachkala 367015Russia

The article presents the results of an experimental study and numerical modelling for the formation and development dynamics of a high-voltage transverse nanosecond discharge generated by a slot cathode in an argon medium at a pressure range of 1–10 Torr. Numerical modelling was carried out under similar experimental conditions for the processes of formation and propagation of ionisation waves, electron density distribution, excited atom and average electron energy in the discharge gap, including the cavity inside the cathode. At a pressure of p=1 Torr, a classical version of a high-voltage discharge is demonstrated to take place with no penetration of the plasma into the cathode cavity and no observed hollow cathode effect. An increase in gas pressure to 5 Torr leads to a penetration of plasma into the cathode cavity with the formation of a cathodic potential drop(CPD) region. Electrons emitted from the side surfaces of the cavity pass through the CPD region without collisions, oscillate inside the cathode cavity;the hollow cathode effect is fully manifested. At р=10 Torr, the modelling results qualitatively coincide with the results at р=5 Torr;in this case, however, hardly any accelerated electrons are observed in the gap between the electrodes, due to their energetic relaxation both inside the cathode cavity and when exiting from it. In both cases, the plasma structure formed at the exit of the cathode cavity involves a concentration of charged particles an order of magnitude higher than that in the rest of the gap, leading to a self-limiting discharge current effect. The results of the numerical modelling are in good agreement with experimental data.

关键词： nanosecond gas discharge numerical simulation argon excited atoms

Seasonal changes in Porteresia coarctata (Tateoka) beds along a subtropical coast

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Chinese Journal of Oceanology and Limnology 2013年第1期31卷 1-9页

作者： ABU HENA m k Department of Animal Science and Fishery Faculty of Agriculture and Food Sciences University Putra Malaysia Bintulu Sarawak Campus

Shoot density, standing crop （above- and below-ground biomass） and habitat of salt marsh grass Porteresia coarctata were investigated along the coast of Bakkhali estuary, Cox＇s Bazar, Bangladesh from January to December 2006. Shoot density of P. coarctata was influenced by season and was found to be higher （〉2 500 shoots/m2） in post-monsoon and minimal in monsoon season; plants were particularly active in vegetative propagation during pre-monsoon. Above-ground biomass was greater along the protected coast compared with the exposed one in this estuary. Below-ground biomass was higher （7.75-269.53 g DW/m2） than that above ground （2.20-114.75 g DW/m2）. Standing crops ofP. coarctata showed a negative relationship （R=-0.77; P〈0.05） with sedimentation rate, while seasonal activity influenced sedimentation. The recorded sedimentation rate was lower （6.09 mg/（cm2·d）） in pre-monsoon and highest （14.55 mg/（cm2·d）） in monsoon season. The mean value of pore water salinity was higher （34.25±65.05） during post-monsoon and lowest （18.0±3.71） in monsoon season. The soil was sandy clay in this P. coarctata bed; it consisted of 86% sand, 13% clay and 1% silt. Soil organic matter dropped during the monsoon season （0.78%-0.67%） and was highest （（2.17±1.42）%-（2.3±1.47）%） during post-monsoon, probably owing to accumulation of decomposed peat on the marsh surface. The mean pore water NH4-N concentration ranged from 2.444-1.65 to 3.33±1.82 μg/L, with a minimum air temperature of 22.09℃ in post-monsoon and a maximum of 31.16℃ in pre-monsoon. Variations of physico-chemical parameters in the soil, water, and climate governed biological parameters of P. coarctata in the Bakkhali estuary, and were comparable with estuarine environments elsewhere.

关键词： standing crop salt marsh Porteresia coarctata Bangladesh

A novel scheme of hybrid entanglement swapping and teleportation using cavity QED in the small and large detuning regimes and quasi-Bell state measurement method

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Chinese Physics B 2016年第10期25卷 45-51页

作者： R Pakniat m k Tavassoly m H Zandi Faculty of Physics Shahid Bahonar University of Kerman Faculty of Physics Atomic and Molecular Group Yazd University Research Group of Optics and Photonics Yazd University

We outline a scheme for entanglement swapping based on cavity QED as well as quasi-Bell state measurement(quasiBSm) methods. The atom–field interaction in the cavity QED method is performed in small and large detuning *** assume two atoms are initially entangled together and, distinctly two cavities are prepared in an entangled coherent–coherent state. In this scheme, we want to transform entanglement to the atom-field system. It is observed that, the fidelities of the swapped entangled state in the quasi-BSm method can be compatible with those obtained in the small and large detuning regimes in the cavity QED method(the condition of this compatibility will be discussed). In addition, in the large detuning regime, the swapped entangled state is obtained by detecting and quasi-BSm approaches. In the continuation,by making use of the atom–field entangled state obtained in both approaches in a large detuning regime, we show that the atomic as well as field states teleportation with complete fidelity can be achieved.

关键词： entanglement swapping quantum teleportation cavity QED quasi-Bell state measurement

Investigation of the inhomogeneous barrier height of an Au/Bi_4Ti_3O_(12)/n-Si structure through Gaussian distribution of barrier height

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Chinese Physics B 2012年第12期21卷 538-543页

作者： m.Gken m.Yildirim Department of Physics Faculty of Arts and SciencesDuzce University

A Au/Bi4Ti3O12/n-Si structure is fabricated in order to investigate its current voltage （IV） characteristics in a temperature range of 300 k-400 k. Obtained I-V data are evaluated by the thermionic emission （TE） theory. Zero-bias barrier height （Ф0） and ideality factor （n） calculated from I-V characteristics, are found to be temperature-dependent such that ФB0 increases with temperature increasing, whereas n decreases. The obtained temperature dependence of ФB0 and linearity in ФB0 versus the n plot, together with a lower barrier height and Richardson constant values obtained from the Richardson plot, indicate that the barrier height of the structure is inhomogeneous in nature. Therefore, I-V characteristics are explained on the basis of Caussian distribution of barrier height.

关键词： Bi4Ti3O12 I-V characterization temperature dependence Gaussian distribution

Effect of anionic ordering on the electronic and optical properties of BaTaO2N：TB-mBJ density functional calculation

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Chinese Physics B 2017年第5期26卷 319-325页

作者： k Bettine O Sahnoun m Sahnoun m Driz LPQ3m University Mustapha Stambouli of Mascara Algeria University Djilali Liabes of Sidi Bel Abbes Algeria

This report presents a first-principles investigation of the structural, electronic, and optical properties of perovskite oxynitrides BaTaO2 N by means of density functional theory（DFT） calculations using the full-potential linearized augmented plane wave（FP-LAPW） method. Three possible structures（P4mm, I4/mmm, and Pmma） are considered according to the TaO4N2 octahedral configurations. The calculated structural parameters are found to be in good agreement with the previous theoretical and experimental results. moreover, the electronic band structure dispersion, total, and partial densities of electron states are investigated to explain the origin of bandgaps and the contribution of each orbital＇s species in the valence and the conduction bands. The calculated minimum bandgaps of the P4 mm, I4/mmm, and Pmma structures are 1.83 e V, 1.59 e V, and 1.49 e V, respectively. Furthermore, the optical properties represented by the dielectric functions calculated for BaTaO2 N show that the I4/mmm phase absorbs the light at a large window in both the visible and UV regions,whereas the other two structures（P4mm and Pmma） are more active in the UV region. Our investigations provide important information for the potential application of this material.

关键词： anionic perovskite octahedral bands dielectric augmented polar ordering struc orbital

Stochastic seismic response of multi-layered soil with random layer heights

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 213-221页

作者： m.Badaoui m.k.Berrah A.mébarki Université Paris-Est Laboratoire Modélisation et Simulation Multi Echelle Ecole Nationale Polytechnique

This paper deals with the effect of layer height randomness on the seismic response of a layered soil. These parameters are assumed to be lognormal random variables. The analysis is carried out via monte Carlo simulations coupled with the stiffness matrix method. A parametric study is conducted to derive the stochastic behavior of the peak ground acceleration and its response spectrum,the transfer function and the amplification factors. The input soil characteristics correspond to a site in mexico City and the input seismic accelerations correspond to the Loma Prieta earthquake. It is found that the layer height heterogeneity causes a widening of the frequency content and a slight increase in the fundamental frequency of the soil profile,indicating that the resonance phenomenon is a concern for a large number of structures. Variation of the layer height randomness acts as a variation of the incident angle,i.e.,a decrease of the amplitude and a shift of the resonant frequencies.

关键词： random layer heights layered soil seismic acceleration lognormal distribution amplification factors mexico City

Insights from an academic endeavor into central nervous system drug discovery

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Neural Regeneration Research 2025年第6期20卷 1717-1718页

作者： Lieve van Veggel An m.Voets Tim Vanmierlo Rudy Schreiber BIOmED Biomedical Research Institute Faculty of Medicine and Life SciencesHasselt UniversityHasseltBelgium Department of Psychiatry and Neuropsychology Division of Translational NeuroscienceEuropean Graduate School of NeuroscienceSchool for Mental Health and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands Section of Psychopharmacology Neuropsychology and PsychopharmacologyFaculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands University mS Center(UmSC) Hasselt-PeltBelgium

Historically,"big pharma"did most central nervous system drug discovery R&D ***,in modern times their"management reductionism"resulted in disappointing pipelines and pharma resided to(late)development,regulatory approval,and marketing(Thong,2015).This had significant consequences for financing and executing research,resulting in a larger role for funding by governments and patient-organizations and a shift of research to academia(mazzucato,2013).

关键词： academic approval consequences