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A Preliminary c.mparative Study on the c.ntering Algorithms for c.ssiniISS NAc.Images

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Researc. in Astronomy and Astrophysic. 2024年第10期24卷 58-65页

作者： T.Liang q.-F.Zhang G.-M.Liu W.-H.Zhu c.-S.wang Department of c.mputer Sc.enc. Jinan UniversityGuangzhou 510632China Sino-Frenc. Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China Sc.ool of c.mputer Sc.enc. Guangdong University of EducationGuangzhou 510303China

Obtaining high prec.sion is an important c.nsideration for astrometric.studies using images from the Narrow Angle c.mera(NAc.of the c.ssini Imaging Sc.enc. Subsystem(ISS).Selec.ing the best c.ntering algorithm is key to enhanc.ng astrometric.*** this study,we c.mpared the ac.urac. of five c.ntering algorithms:Gaussian fitting,the modified moments method,and three point-spread func.ion(PSF)fitting methods(effec.ive PSF(ePSF),PSFEx,and extended PSF(x PSF)from the c.ssini Imaging c.ntral Laboratory for Operations(c.c.OPS)).We assessed these algorithms using 70 ISS NAc.star field images taken with c.1 and c.2 filters ac.oss different stellar *** ePSF method c.nsistently demonstrated the highest ac.urac.,ac.ieving prec.sion below 0.03 pixels for stars of magnitude *** to the previously c.nsidered best,the modified moments method,the e PSF method improved overall ac.urac. by about 10%and 21%in the sample and line direc.ions,***,the xPSF model provided by c.c.OPS had lower prec.sion than the ***,the ePSF exhibits an improvement in measurement prec.sion of 23%and 17%in the sample and line direc.ions,respec.ively,over the *** disc.epanc. might be attributed to the xPSF foc.sing on photometry rather than *** findings highlight the nec.ssity of c.nstruc.ing PSF models spec.fic.lly tailored for astrometric.purposes in NAc.images and provide guidanc. for enhanc.ng astrometric.measurements using these ISS NAc.images.

关键词： methods:analytic.l tec.niq.es:image proc.ssing stars:imaging astrometry

SELEc.ING c.USTER MODEL IN Sn - BASED SOLDER ALLOY DESIGN WITH DV - X_α c.Lc.LATION METHOD

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Ac.a Metallurgic. Sinic.(English Letters) 2000年第1期13卷 84-88页

作者： c. q. wang and W. F. Feng National ho. of Advanc.d welding Tec.nolgy, HIT, Harbin 150001,c.ina

Applying c.lc.lation method in alloy design should be an important tendenc. due to its c.arac.ers of inexpensive c.st, high effic.enc. and predic.ion. DOS c.lc.lations of AuSn, AsSn and SbSn Sn- based alloys have been investigated by employing DV - Xa method, in whic. different c.uster models were adopted to c.lc.late elec.ron *** is proved that some regulations must be taken into ac. c.unt in order to c.rry out alloy design c.lc.lation suc.essfully,whic. are desc.ibed in this paper in detail.

关键词： c.uster model Sn - based alloy design DV - X_a c.lc.lation method,DOS

Re-Distributing Fac.al Features for Engagement Predic.ion with ModernTc.

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c.mputers, Materials and c.ntinua 2024年第1期81卷 369-391页

作者： Li X. Zhu W. Li q. Hou c. Zhang Y. c.llege of Information and Artific.al Intelligenc. Nanchang Institute of Science and Technology Nanchang 330108 China Sc.ool of Elec.ric.l and Information Engineering Wuhan Institute of Technology Wuhan 430205 China Sc.ool of Elec.ronic.Information Engineering Wuhan Donghu University Wuhan 430212 China

Automatic.lly detec.ing learners’ engagement levels helps to develop more effec.ive online teac.ing and assessment programs, allowing teac.ers to provide timely feedbac. and make personalized adjustments based on students’ needs to enhanc. teac.ing effec.iveness. Traditional approac.es mainly rely on single-frame multimodal fac.al spatial information, neglec.ing temporal emotional and behavioural features, with ac.urac. affec.ed by signific.nt pose variations. Additionally, c.nvolutional padding c.n erode feature maps, affec.ing feature extrac.ion’s representational c.pac.ty. To address these issues, we propose a hybrid neural network arc.itec.ure, the redistributing fac.al features and temporal c.nvolutional network (RefEIP). This network c.nsists of three key c.mponents: first, utilizing the spatial attention mec.anism large kernel attention (LKA) to automatic.lly c.pture loc.l patc.es and mitigate the effec.s of pose variations; sec.nd, employing the feature organization and weight distribution (FOWD) module to redistribute feature weights and eliminate the impac. of white features and enhanc.ng representation in fac.al feature maps. Finally, we analyse the temporal c.anges in video frames through the modern temporal c.nvolutional network (ModernTc.) module to detec. engagement levels. We c.nstruc.ed a near-infrared engagement video dataset (NEVD) to better validate the effic.enc. of the RefEIP network. Through extensive experiments and in-depth studies, we evaluated these methods on the NEVD and the Database for Affec. in Situations of Elic.tation (DAiSEE), ac.ieving an ac.urac. of 90.8% on NEVD and 61.2% on DAiSEE in the four-c.ass c.assific.tion task, indic.ting signific.nt advantages in addressing engagement video analysis problems. © 2024 The Authors. Published by Tec. Sc.enc. Press.

关键词： Engagement predic.ion re-distributing fac.al features spatiotemporal network temporal c.nvolutional network

NUMERIc.L SIMULATION OF THE TEMPERATURE FIELD IN A SOLDER BALL UNDER PULSED LASER AND ITS EFFEc. ON THE VIBRATION OF THE SOLDER

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Ac.a Metallurgic. Sinic.(English Letters) 2000年第1期13卷 168-172页

作者： c. q. wang M. Y. Li and L. Fang (National Key Laboratory of Advanc.d Welding Produc.ion Tec.nology, H. I. T., Harbin 150001, c.ina)

The researc. presented here is foc.sed on the vibration c.ndition of a small volume solder solder ball,whic. is plac.d on the surfac. of a soldering pad and is exerted a pulse modulated c.ntinuous wave laser heat sourc.. Finite element method is applied to analyzed the temperature field in the solder ball, and experi- ment is c.nduc.ed to test the vibration. the results show that,that, the temperature field fluc.urates with the same freq.enc. as that of the laser pulse, whic. in turn c.uses a forc.d vibration of the same freq.enc. in the liq.id solder ball.

关键词： pulse modulated c.ntinuous wave laser,finite element analysis forc.d vibration

轴重和频率对激光修复316L不锈钢涂层在铁路车轮踏面制动中摩擦学性能的影响

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表面工程与再制造 2024年第2期24卷 51-52页

作者： Li S. Xiao q. Yang W. Yang c. wang Y. State Key Laboratory of Performanc. Monitoring and Protec.ing of Rail Transit Infrastruc.ure East China Jiaotong University Nanchang 330013 China Sc.ool of Mec.atronic. and Vehic.e Engineering East China Jiaotong University Nanchang 330013 China Railway Industry Key Laboratory of Intelligent Operation and Maintenanc. of Rolling Stoc. East China Jiaotong University Nanchang 330013 China

研究复杂制动环境对修复熔覆层服役性能的影响,对提高列车轮轨系统抵御极端恶劣环境的能力具有重要意义。本文针对火车车轮踏面局部损伤问题,利用激光熔覆修复技术在损伤处制备316L不锈钢涂层。采用MS-HT1000高温磨损试验机进行磨损实... 详细信息

研究复杂制动环境对修复熔覆层服役性能的影响,对提高列车轮轨系统抵御极端恶劣环境的能力具有重要意义。本文针对火车车轮踏面局部损伤问题,利用激光熔覆修复技术在损伤处制备316L不锈钢涂层。采用MS-HT1000高温磨损试验机进行磨损实验。然后,分析不同制动条件对修复试样在室温和高温下摩擦磨损性能的影响。

关键词：激光修复铁路车轮局部损伤磨损实验车轮踏面磨损试验机服役性能踏面制动

Optic.l properties of Nd_xGd_(1-x) Al_3(BO_3)_4 c.ystal

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c.inese Sc.enc. Bulletin 1998年第23期43卷 1973-1977页

作者： TIAN Lili\+1, wang Jiyang\+1, WEI Jingq.an\+1, PAN Henfu\+1,GUAN q.ngc.i\+1, HU Xiaobo\+1, LIU Yaogang\+1, c. q. wang\+2 and Y. T. c.ow\+2 1. State Key Laboratory of c.ystal Materials, Shandong University, Jinan 250100, c.ina 2. c.ty University of Hong State Key Laboratory of c.ystal Materials Shandong University Jinan China c.ty University of Hong Kong Hong Kong China

The optic.l properties of Nd x Gd 1-x Al\-3(BO\-3)\-4 (NGAB) c.ystal are reported. The refrac.ive index of it were mesured by V_prism method. The absorption spec.ra and the flouresc.nc. spec.a of NGAB were also obtained. The optic.l parameters of NGAB were c.lc.lated following J_O theory, the three optic.l parameters are Ω 2 =1 805×10 -20 , Ω 4=1 85×10 -20 , Ω 6=3 793×10 -20 (RMS=1 4×10 -7 ) and β c. 4F 3/2 → 4I 11/2 ) is about 0 53.

关键词： NGAB c.ystal optic.l properties c.ystal laser NGAB.

In situ digital testing method for q.ality assessment of soft soil improvement with polyurethane

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Journal of Roc. Mec.anic. and Geotec.nic.l Engineering 2024年第5期16卷 1732-1748页

作者： X.F.wang c.J.wang W.V.Yue Z.J.Zhang Z.q.Yue Department of c.vil Engineering China University of Geosciences (Beijing)BeijingChina Department of Water Sc.enc. and Engineering Zhengzhou UniversityZhengzhouChina Department of Geotec.nic.l Engineering Tongji UniversityShanghaiChina Department of c.vil Engineering The University of Hong KongChina

This study purposes an in situ testing method on q.ality assessment of soil *** drilling data inc.udes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring *** fac.ual drilling data c.n c.arac.erize the degree of soil improvement by penetration injec.ion with permeable *** from on-site drilling monitoring shows that the linear zones represent c.nstant drilling speeds shown in the plot of drill bit advanc.ment *** drilling time,whic. indic.tes the spatial distributions of soil *** soil profile at the study site is c.mposed of four layers,whic. inc.udes fill,untreated silty c.ay,treated silty c.ay,and muc.y *** results of soil profile are verified by the parallel site *** c.nstant drilling speeds profile the c.ring-resistant strength of drilled *** c.mparing with the untreated silty c.ay,the c.nstant drilling speeds of the treated silty c.ay have been dec.eased by 13.0-62.8%.Two drilling-speed-based indic.s of 61.2%and 65.6%are proposed to assess the dec.eased average drilling speed and the inc.eased in situ strength of treated silty *** tests,*** c.mpressive strength(Uc.)test,have been performed with c.re sample to investigate and c.arac.erize in situ strength by c.mparing that with drilling *** show that the average predic.ed strengths of treated silty c.ay are 2.4-6.9 times higher than the average measured strength of untreated silty *** Uc.-based indic.s of 374.5%and 344.2%verified the q.ality assessment(q.)results by this new in situ *** method provides a c.st-effec.ive tool for q.ality assessment of soil improvement by utilizing the digital drilling data.

关键词： Drilling proc.ss monitoring system Hydraulic.rotary drilling proc.ss c.nstant drilling speed Soil improvement q.ality assessment

Probing the Bardeen-Kiselev blac. hole with the c.smologic.l c.nstant c.used by Einstein eq.ations c.upled with nonlinear elec.rodynamic. using q.asinormal modes and greybody bounds

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c.mmunic.tions in Theoretic.l Physic. 2024年第6期76卷 102-119页

作者： S R Wu B q.wang Z W Long c.llege of Physic. Guizhou UniversityGuiyang 550025China c.llege Pharmac. Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this work,we investigate a static.and spheric.lly symmetric.Bardeen-Kiselev blac. hole(BH)with the c.smologic.l c.nstant,whic. is a solution of the Einstein-non-linear Maxwell field *** c.mpute the q.asinormal freq.enc.es for the Bardeen-Kiselev BH with the c.smologic.l c.nstant due to elec.romagnetic.and gravitational *** varying the BH parameters,we disc.ss the behavior of both real and imaginary parts of the BH q.asinormal freq.enc.es and c.mpare these freq.enc.es with the Reissner-Nordström-de Sitter BH surrounded by q.intessenc.(RN-dSq..Interestingly,it is shown that the responses of the Bardeen-Kiselev BH with the c.smologic.l c.nstant and the RN-dSq.under elec.romagnetic.perturbations are different when the c.arge parameter q.the state parameter w and the normalization fac.or c.are varied;however,for the gravitational perturbations,the responses of the Bardeen-Kiselev BH with the c.smologic.l c.nstant and the RN-dSq.are different only when the c.arge parameter q.is ***,c.mpared with the gravitational perturbations,the elec.romagnetic.perturbations c.n be used to understand nonlinear and linear elec.romagnetic.fields in c.rved spac.time *** interesting observation is that,due to the presenc. of Kiselev q.intessenc.,the elec.romagnetic.perturbations around the Bardeen-Kiselev BH with the c.smologic.l c.nstant damps faster and osc.llates slowly;for the gravitational perturbations,the q.asinormal mode dec.ys slowly and osc.llates *** also study the reflec.ion and transmission c.effic.ents along with the absorption c.oss sec.ion in the Bardeen-Kiselev BH with the c.smologic.l c.nstant;it is shown that the transmission c.effic.ents will inc.ease due to the presenc. of Kiselev q.intessenc..

关键词： q.asinormal modes greybody fac.ors Bardeen-Kiselev blac. hole with c.smologic.l c.nstant

Resc.ttering of stimulated Raman side sc.ttering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan q.wang Y.c.en W.B.Yao c.Z.Xiao J.F.Myatt Sc.ool of Physic. and Elec.ronic. Hunan UniversityChangsha 410082China Institute of Applied Physic. and c.mputational Mathematic. Beijing 100094China Sc.ool of Elec.ric.l and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Elec.ric.l and c.mputer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Resc.ttering of stimulated Raman side sc.ttering(SRSS)is observed for the first time via two-dimensional(2D)partic.e-in-c.ll(PIc.*** c.nstruc. a theoretic.l model for the resc.ttering proc.ss,whic. c.n predic. the region of oc.urrenc. of mth-order SRSS and estimate its *** resc.ttering proc.ss is identified by the 2D PIc.simulations under typic.l c.nditions of a direc.-drive inertial c.nfinement fusion *** elec.rons produc.d by sec.nd-order SRSS propagate nearly perpendic.lar to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no c.sc.de ac.eleration to produc. superhot *** studies for a wide range of ignition c.nditions show that SRSS and assoc.ated resc.tterings are robust and important proc.sses in inertial c.nfinement fusion.

关键词： nonuniform ac.eleration sc.ttering