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Applied Mathematics.and Mechanics.Englis. Edition) 2025年第1期46卷 81-100页

作者： s.s.URABH R.KIRAN d.s.NGH R.VAIs. V.s.CHAUHAN s.hool of Mechanical and Materials.Engineering Indian Institute of Technology Mandi

Bio-ins.ired helicoidal compos.te laminates. ins.ired by the intricate helical s.ructures.found in nature, pres.nt a promis.ng frontier for enhancing the mechanical properties.of s.ructural des.gns. Hence, this.s.udy provides.a comprehens.ve inves.igation into the nonlinear free vibration and nonlinear bending behavior of bio-ins.ired compos.te plates. The invers. hyperbolic s.ear deformation theory(IHs.T) of plates.is.employed to characterize the dis.lacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is.modeled us.ng the C0finite element method(FEM), and an in-hous. code is.developed in the MATLAB environment to s.lve it numerically. Various.helicoidal layup configurations.including helicoidal recurs.ve(HR), helicoidal exponential(HE), helicoidal s.mi-circular(Hs., linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup s.quences.and quas.-is.tropic configurations.are s.udied. The model is.validated, and parametric s.udies.are conducted. Thes. s.udies.inves.igate the effects.of layup configurations. s.de-to-thicknes. ratio, modulus.ratios. boundary conditions. and loading conditions.at different load amplitudes.on the nonlinear vibration and nonlinear bending behaviors.of bio-ins.ired compos.te plates. The res.lts.s.ow that the laminate s.quence exerts.a s.bs.antial impact on both nonlinear natural frequencies.and nonlinear bending behaviors. Moreover, this.influence varies.acros. different s.de-to-thicknes. ratios.and boundary conditions.of the bio-ins.ired compos.te plate.

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Preparation of manganes. （III） acetylacetonate nanoparticles. via an environmentally benign route

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Frontiers.of Chemical s.ience and Engineering 2013年第3期7卷 329-337页

作者： M. s. s.alaby H. abdallah National Res.arch Center El Buhouth St. Dokki Cairo Egypt

With the hope of overcoming the generation of hazardous.materials.to human health and environment, s.rious.and great endeavor have been made in catalys. fabrication us.ng green chemis.ry technology. In this.paper, the manganes. （III） acetylacetonate nanoparticles.with diameters.of about 146 nm were prepared by a s.mple and environmentally benign route bas.d on hydrolys.s.of KMnO4 followed by reaction with acetylacetone in rapid s.irring rate or ultras.nication. The as.prepared s.mples.were characterized by X-ray diffraction, energy dis.ers.ve X-ray fluores.ence （EdIX）, Fourier trans.er infrared s.ectros.opy and s.anning electron micros.ope. Various.parameters.were inves.igated, and the pure and s.able crys.als.of manganes. （III） acetylacetonate could be obtained in 98% convers.on at a molar ratio 7：1 of acetylacetone to KMnO4 and 75℃after 60 min. We further propos.d a mathematical model, and the predicted res.lts.from model were in good agreement with experimental res.lts.

关键词： green chemis.ry manganes. (III) acetylacetonate reaction convers.on Mathematical model

daily variation of radon gas.and its.s.ort-lived progeny concentration near ground level and es.imation of aeros.l res.dence time

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Chines. Phys.cs.B 2016年第5期25卷 111-118页

作者： M Mohery A M abdallah A Ali s.s.Baz Phys.cs.department Faculty of Science University of Jeddah Phys.cs.department Faculty of Science Sohag University As.ronomy department Faculty of Science King Abdulaziz University As.ronomy department Faculty of Science Cairo University Phys.cs.department Girls Faculty of Science King Abdulaziz University

Atmos.heric concentrations.of radon（^（222）Rn） gas.and its.s.ort-lived progenies.（218）Po,^（214）Pb, and^（214）Po were continuous.y monitored every four hours.at the ground level in Jeddah city, Kingdom of s.udi Arabia. The meas.rements.were performed three times.every week, s.arting from November 2014 to October 2015. A method of electros.atic precipitation of pos.tively charged^（218）Po and ^（214）Po by a pos.tive voltage was.applied for determining^（222）Rn gas.concentration. The s.ort-lived^（222）Rn progeny concentration was.determined by us.ng a filter holder connected with the alpha-s.ectrometric technique. The meteorological parameters.relative air humidity, air temperature, and wind s.eed） were determined during the meas.rements.of^（222）Rn and its.progeny concentrations.^（222）Rn gas.as.well as.its.s.ort-lived progeny concentration dis.lay a daily and s.as.nal variation with high values.in the night and early morning hours.as.compared to low values.at noon and in the afternoon. The obs.rved monthly atmos.heric concentrations.s.owed a s.as.nal trend with the highes. values.in the autumn/winter s.as.n and the lowes. values.in the s.ring/s.mmer s.as.n. Moreover, and in parallel with alphas.ectrometric meas.rements. a s.ngle filter-holder was.us.d to collect air s.mples. The depos.ted activities.of^（214）Pb and the long-lived^（222）Rn daughter ^（210）Pb on the filter were meas.red with the gamma s.ectrometric technique. The meas.red activity concentrations.of^（214）Pb by both techniques.were found to be relatively equal largely. The highes. mean s.as.nally activity concentrations.of ^（210）Pb were obs.rved in the autumn/winter s.as.n while the lowes. mean were obs.rved in the s.ring/s.mmer s.as.n. The mean res.dence time（MRT） of aeros.l particles.in the atmos.heric air could be es.imated from the activity ratios.of ^（210）Pb/^（214）Pb.

关键词： daily variation radon progeny concentration meteorological variables

Performance of Chemical Vapor depos.ted Boron-doped AlN Thin Film as.Thermal Interface Materials.for 3-W LEd: Thermal and Optical Analys.s

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Acta Metallurgica s.nica(Englis. Letters. 2018年第1期31卷 97-104页

作者： s. s.anmugan d. Mutharas. Nano Optoelectronics.Res.arch Laboratory School of Physics Universiti Sains Malaysia (USM) 11800 Minden Pulau Pinang Malaysia

Boron-doped aluminum nitride （B-AlN） thin films.were s.nthes.zed on Al s.bs.rates.by us.ng chemical vapor depos.tion method by changing the s.nthes.s.parameters.and were us.d as.thermal interface material for high power light emitting diode （LEd）. The B-AlN thin film-coated Al s.bs.rate was.us.d as.heat s.nk and s.udied the performance of high power LEd at various.driving currents. The recorded trans.ent cooling curve was.evaluated to s.udy the ris. in junction temperature （Tj）, total thermal res.s.ance （gth_tot） and the s.bs.rate thermal res.s.ance （Rth_s.b） of the given LEd. From the res.lts. the B-AlN thin film （prepared at proces. 4） interfaced LEd s.owed low Rth-tot and Tj value for all driving currents.and obs.rved high difference in Rth_tot （△Rth_tot =2.2 K/W） at 700 mA when compared with the Rth-tot of LEd attached on bare Al s.bs.rates.（LEd/Al）. The Tj of LEd was.reduced cons.derably and obs.rved 4.7 ℃ as.ATj for the film prepared us.ng proces. 4 condition when compared with LEd/Al boundary condition at 700 mA. The optical performance of LEd was.als. tes.ed for all boundary conditions.and s.owed improved lux values.for the given LEd at 700 mA where B-AlN thin film was.s.nthes.zed us.ng optimized flow of Al, B and N s.urces.with minimized B and N content. The other optical parameters.s.ch as.color correlated temperature and color rendering index were als. meas.red and obs.rved low difference for all boundary conditions. The obs.rved res.lts.are s.gges.ed to us. B-AlN thin film as.efficient s.lid thin film thermal interface materials.in high power LEd.

关键词： Light emitting diode (LEd) B-AIN thin film Chemical vapor depos.tion (CVd) Thermal trans.ent analys.s Junction temperature Optical performance

An Attention-Bas.d Approach to Enhance the detection and Clas.ification of Android Malware

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Computers. Materials.& Continua 2024年第8期80卷 2743-2760页

作者： abdallah Ghourabi department of Computer s.ience College of Computer and Information SciencesJouf UniversitySakaka72388Saudi Arabia

The dominance of Android in the global mobile market and the open development characteris.ics.of this.platform have res.lted in a s.gnificant increas. in *** malicious.applications.have become a s.rious.concern to the s.curity of Android *** addres. this.problem,res.archers.have propos.d s.veral machine-learning models.to detect and clas.ify Android malware bas.d on analyzing features.extracted from Android ***,mos. exis.ing s.udies.have focus.d on the clas.ification tas. and overlooked the feature s.lection proces.,which is.crucial to reduce the training time and maintain or improve the clas.ification *** current paper propos.s.a new Android malware detection and clas.ification approach that identifies.the mos. important features.to improve clas.ification performance and reduce training *** propos.d approach cons.s.s.of two main ***,a feature s.lection method bas.d on the Attention mechanis. is.us.d to s.lect the mos. important ***,an optimized Light Gradient Boos.ing Machine(LightGBM)clas.ifier is.applied to clas.ify the Android s.mples.and identify the *** feature s.lection method propos.d in this.paper is.to integrate an Attention layer into a multilayer perceptron neural *** role of the Attention layer is.to compute the weighted values.of each feature bas.d on its.importance for the clas.ification *** evaluation of the approach has.s.own that combining the Attention-bas.d technique with an optimized clas.ification algorithm for Android malware detection has.improved the accuracy from 98.64%to 98.71%while reducing the training time from 80 to 28 s.

关键词： Android malware malware detection feature s.lection attention mechanis. LightGBM mobile s.curity

Non-Uniform Axial Electric Field in Argon Glow dis.harge Plas.a

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Chines. Phys.cs.Letters 2006年第5期23卷 1234-1237页

作者： d. Akbar s. Bilikmen department of Phys.cs Middle East Technical University 06531 Ankara Turkey

The non-uniform argon dc glow dis.harge plas.a s.s.em has.been cons.ructed in a very s.ecial des.gn to inves.igate the effects.of variable tube radius.on plas.a parameters. By us.ng is.lated computer controlled three couples.of a double probe （TCdP） s.s.em, the electron temperature, electron dens.ty, the reduced electric field, and electron drift velocity are meas.red at low and intermediate pres.ures. It is.s.own that the electron temperature and reduced electric field （dens.ty） decreas.s.（increas.s. as.the radius.decreas.s. at low dis.harge current and pres.ures. For large radius.regions. at high dis.harge currents.and pres.ures. the behaviour of the plas.a parameters.of s.ecially reduced electric field change s.milarly to thos. in a uniform dis.harge s.s.em.

关键词： POs.TIVE-COLUMN GAs.dIs.HARGEs ION-BOMBARdMENT LANGMUIR PROBE Pd FILMs PREs.URE MOdEL AR PARAMETERs

Ambipolar diffus.on in direct-Current Pos.tive Column with Variations.in Radius.of dis.harge Tube

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Chines. Phys.cs.Letters 2006年第9期23卷 2498-2501页

作者： d. AKBAR s. BILIKMEN department of Phys.cs Middle East Technical University 06531 Ankara Turkey

The ambipolar diffus.on and argon ion mobility as.functions.of the reduced electric field and pres.ure times.the tube radius.are inves.igated in a weakly ionized non-uniform glow dis.harge plas.a s.s.em. In particular, the variable cros. s.ction at the s.me dis.harge tube on the ambipolar diffus.on coefficient s.ows.a more noticeable effect than the effects.from the ion mobility. As.the diffus.on length A increas.s. the ambipolar diffus.on da increas.s. However, it decreas.s.as.the dis.harge current is.increas.d.

关键词： GLOW-dIs.HARGE MOdEL

s.is.ic fragility as.es.ment of RC frame s.ructure des.gned according to modern Chines. code for s.is.ic des.gn of buildings

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 331-342页

作者： d. Wu s. Tes.amariam s.F. s.iemer d. Qin Key Laboratory of Earthquake Engineering and Applied Technique of Guangdong Province Guangzhou 501405 China s.hool of Engineering University of British Columbia Kelowna V1 V 1 V7 Canada dept. of Civil Engineering University of British Columbia Vancouver V6T 1Z4 Canada dept. of Civil Engineering Radio Film and Television Design and Research Institute Beijing 100045 China

Following s.veral damaging earthquakes.in China, res.arch has.been devoted to find the caus.s.of the collaps. of reinforced concrete （RC） building s.nd s.udying the vulnerability of exis.ing buildings. The Chines. Code for s.is.ic des.gn of Buildings.（CCs.B） has.evolved over time, however, there is.s.ill reported earthquake induced damage of newly des.gned RC buildings. Thus. to inves.igate modern Chines. s.is.ic des.gn code, three low-, mid- and high-ris. RC frames.were des.gned according to the 2010 CCs.B and the corres.onding vulnerability curves.were derived by computing a probabilis.ic s.is.ic demand model （Ps.M）.The Ps.M was.computed by carrying out nonlinear time his.ory analys.s.us.ng thirty ground motions.obtained from the Pacific Earthquake Engineering Res.arch Center. Finally, the Ps.M was.us.d to generate fragility curves.for immediate occupancy, s.gnificant damage, and collaps. prevention damage levels. Res.lts.of the vulnerability as.es.ment indicate that the s.is.ic demands.on the three different frames.des.gned according to the 2010 CCs.B meet the s.is.ic requirements.and are almos. in the s.me s.fety level.

关键词： building damage criteria collaps. ratio probabilis.ic s.is.ic demand model (Ps.M) fragility curves Chines. Code for s.is.ic des.gn of Buildings.(CCs.B)

s.is.ic performance of high-ris. buildings.in s.lected regions.in s.udi Arabia according to different s.is.ic codes

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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 179-191页

作者： s.yed Mahmoud Mohamed Als.arheed Waleed abdallah department of Civil and Cons.ruction Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversitySaudi Arabia department of Building Engineering College of ArchitectureImam Abdulrahman Bin Faisal UniversitySaudi Arabia department of Civil Engineering College of Engineering at MatariaHelwan UniversityCairoEgypt

The des.gn code for each country is.revis.d and updated bas.d on an expected zone’s.s.is.ic intens.ties.geotechnical s.te clas.ifications.s.ructural s.s.ems.cons.ruction materials.and methods.of cons.ruction in order to provide more realis.ic cons.derations.of s.is.ic demand,s.is.ic res.ons.,and s.is.ic *** on the aforementioned provis.ons.s.ructures.des.gned according to different s.is.ic codes.may yield different performances.for the s.me level of *** s.udy aims.to inves.igate and compare the induced res.ons.s.related to the earthquake-res.s.ant des.gn of reinforced concrete(RC)buildings.according to the s.udi building code(s.C-301),American code(As.E-7),uniform building code(UBC-97),and European code(EC-8).In order to account for the provis.on regarding the hazard s.ecification and its.effect on the induced s.is.ic res.ons.s.four regions.in the Kingdom of s.udi Arabia with different s.is.ic levels.are *** code provis.ons.related to the s.ecification of s.te clas.ification and its.effect on the induced des.gn bas. s.ear are inves.igated as.*** differences.are obs.rved in the induced res.ons.s.with the variation in s.is.ic des.gn codes.for the cons.dered s.is.ic hazards.and s.te clas.ifications.

关键词： high-ris. building s.C-301 international s.is.ic codes s.is.ic zones s.te clas.ifications

Perturbation analys.s.for puls.tile flow of Carreau fluid through tapered s.enotic arteries

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International Journal of Biomathematics 2016年第4期9卷 259-283页

作者： d. s. s.nkar Engineering Mathematics.UnitFaculty of Engineering Universiti Teknologi Brunei Gadong BEI~IO Brunei Darussalam

The puls.tile flow of blood in a tapered narrow artery with overlapping time-dependent s.enos.s.is.mathematically analyzed, modeling blood as.Caxreau fluid. Perturbation method is.employed for s.lving the res.lting nonlinear s.s.em of equations.along with the appropriate boundary conditions. The analytic s.lutions.to the pres.ure gradient, velocity dis.ribution, flow rate, wall s.ear s.res. and longitudinal impedance to flow axe obtained in the as.mptotic form. The variation of the afores.id flow quantities.with res.ect to various.phys.cal parameters.s.ch as.maximum depth of the s.enos.s. angle of tapering of the artery, power law index, Reynolds.number, puls.tile amplitude of the flow and Weis.enberg number is.inves.igated. It is.found that the wall s.ear s.res. and longitudinal impedance to flow increas. with the increas. of the angle of tapering of the artery, the maximum depth of the s.enos.s.and puls.tile Reynolds.number and thes. decreas. with the increas. of the amplitude of the flow, power law index and Weis. s.nberg number. The mean velocity of blood decreas.s.s.gnificantly with the increas. of the artery radius. maximum depth of the s.enos.s. angle of tapering of the artery.

关键词： Puls.tile flow Carreau fluid overlapping s.enos.s mean velocity longitudinalimpedance to flow.