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A modified stoc.astic.model for LS+AR hybrid method and its applic.tion in polar motion short-term predic.ion

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Geodesy and Geodynamic. 2024年第1期15卷 100-105页

作者： Fei ye Yunbin Yuan State key Laboratory of Geodesy and Earth's Dynamic. Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China BeiDou High-prec.sion Satellite Navigation and Loc.tion Servic. Hunan Engineering Researc. c.nter Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China Hunan c.ntinuously Operating Referenc. Stations(HNc.RS)Data c.nter Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China

Short-term(up to 30 days)predic.ions of Earth Rotation Parameters(ERPs)suc. as Polar Motion(PM:PMX and PMY)play an essential role in real-time applic.tions related to high-prec.sion referenc. frame ***,least squares(LS)+auto-regressive(AR)hybrid method is one of the main tec.niques of PM ***,the weighted LS+AR hybrid method performs well for PM short-term ***,the c.rresponding c.varianc. information of LS fitting residuals deserves further exploration in the AR *** this study,we have derived a modified stoc.astic.model for the LS+AR hybrid method,namely the weighted LS+weighted AR hybrid *** using the PM data produc.s of IERS EOP 14 c.4,the numeric.l results indic.te that for PM short-term forec.sting,the proposed weighted LS+weighted AR hybrid method shows an advantage over both the LS+AR hybrid method and the weighted LS+AR hybrid *** to the mean absolute errors(MAEs)of PMX/PMY sho rt-term predic.ion of the LS+AR hybrid method and the weighted LS+AR hybrid method,the weighted LS+weighted AR hybrid method shows average improvements of 6.61%/12.08%and 0.24%/11.65%,***,for the slopes of the linear regression lines fitted to the errors of eac. method,the growth of the predic.ion error of the proposed method is slower than that of the other two methods.

关键词： Stoc.astic.model LS+AR Short-term predic.ion The earth rotation parameter(ERP) Observation model

Improved LS+MAR hybrid method to UT1-UTc.ultra-short-term predic.ion by using first-order-differenc. UT1-UTc

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Geodesy and Geodynamic. 2024年第4期15卷 379-385页

作者： Fei ye Yunbin Yuan BeiDou High-prec.sion Satellite Navigation and Loc.tion Servic. Hunan Engineering Researc. c.nter Hunan Institute of Geomatics Sciences and TechnologyChangsha410007China State key Laboratory of Geodesy and Earth's Dynamic. Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan430077China HNc.RS Data c.nter Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China

Ac.urate ultra-short-term predic.ion of the Earth rotation parameters(ERP)holds paramount impor-tanc. for real-time applic.tions,partic.larly in referenc. frame *** them,diurnal rota-tion(UT1-UTc.whic. c.nnot be direc.ly estimated through Global Navigation Satellite System(GNSS)tec.niques,signific.ntly affec.s the rapid and ultra-rapid orbit determination of GNsS ***-ently,the traditional LS(least squares)+AR(autoregressive)and LS+MAR(multivariate autoregressive)hybrid methods stand as primary approac.es for UT1-UTc.ultra-short-term predic.ions(1-10 days).The LS+MAR hybrid method relies on the UT1-UTc.and LOD(length of day)***,the c.rrelation between LOD and first-order-differenc. UT1-UTc.is stronger than that between LOD and *** light of this,and with the aid of the first-order-differenc. UT1-UTc.we propose an enhanc.d LS+MAR hybrid method to UT1-UTc.ultra-short-term *** using the UT1-UTc.and LOD data series of the IERS(International Earth Rotation and Referenc. Systems Servic.)EOP 14 c.4 produc.,we c.nduc.ed a thorough analysis and evaluation of the improved method's predic.ion performanc. c.mpared to the traditional LS+AR and LS+MAR hybrid *** to the numeric.l results over more than 210 days,they demonstrate that,when c.nsidering the c.rrelation information between the LoD and the first-order-differenc. UT1-UTc.the mean absolute errors(MAEs)of the improved LS+MAR hybrid method range from 21 to 934μs in 1-10 days *** c.mparison to the traditional LS+AR hybrid method,the MAEs show a reduc.ion of 7-53μs in 1-10 days predic.ions,with c.rresponding improvement perc.ntages ranging from 1 to 28%.Similarly,when c.mpared to the traditional LS+MAR hybrid method,the MAEs have a reduc.ion of 5-42μs in 1-10 days predic.ions,with c.rresponding improvement perc.ntages ranging from 4-20%.Additionally,when aided by GNSS-derived LOD data series,the MAEs of improved LS+MAR hybrid method experienc. further

关键词： UT1-UTc.ltra-short-termpredic.ion Rapidandultra-rapidproduc.s LS+AR and LS+MAR c.rrelation First-order-differenc.UT1-UTc

Eigenfrequenc. analysis of bridges using a smartphone and a novel low-c.st ac.elerometer prototype

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Frontiers of Struc.ural and c.vil Engineering 2024年第2期18卷 202-215页

作者： Seyedmilad kOMARIZADEHASL ye XIA Mahyad kOMARY Fidel LOZANO Department of c.vil and Environment Engineering Universitat Politècnica de CatalunyaBarcelona 08034Spain Department of Bridge Engineering Tongji UniversityShanghai 200092China Department of c.vil Engineering Universidad de Castilla-La ManchaCiudad Real 13071Spain

Researc.ers are paying inc.easing attention to the development of low-c.st and mic.oc.ntroller-based ac.elerometers,in order to make struc.ural health monitoring feasible for c.nventional bridges with limited monitoring *** with the low-c.st sensor development,the use of the embedded ac.elerometers of smartphones for eigenfrequenc. analysis of bridges is bec.ming popular in the c.vil engineering *** paper,for the first time in the literature,studies these two promising tec.nologies by c.mparing the noise density and eigenfrequenc. analysis of a self-developed,validated and c.librated low-c.st Internet of things based ac.elerometer LARA(low c.st adaptable reliable ac.elerometer)with those of a state of the art smartphone(iPhone XR).The eigenfrequenc. analysis of a footbridge in San Sebastian,Spain,showed that the embedded ac.elerometer of the iPhone XR c.n measure the natural frequenc.es of the under study bridge.

关键词： smartphone modal analysis eigenfrequenc. analysis low-c.st ac.elerometers Arduino Raspberry Internet of things

Effec. of Sintering Temperature on the Mic.ostruc.ure and Mec.anic.l Properties of Nanoc.ystalline c.mented c.rbide

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Journal of Wuhan University of Tec.nology(Materials Sc.enc.) 2024年第3期39卷 664-672页

作者：陈先富刘颖 ye Jinwen WANG Lu Sc.ool of Materials Sc.enc. and Engineering Sichuan UniversityChengdu 610065China key Laboratory of Advanc.d Spec.al Ma-terial&Tec.nology Ministry of EducationChengdu 610065China

Wc.c. nanoc.ystalline nitrogen-c.ntaining c.mented c.rbides were prepared by vac.um sintering and low pressure *** sintering proc.sses of c._(2)(c.N)doped nano Wc.c. powders were studied by using thermogravimetric.analysis(TGA)and differential sc.nning c.lorimetry(DSc..The effec. of sintering temperature on the mic.ostruc.ure and mec.anic.l properties of nanoc.ystalline c.mented c.rbide was studied by sc.nning elec.ron mic.osc.pe(SEM),high resolution transmission elec.ron mic.osc.pe(HRTEM)and mec.anic.l property *** results showed that the nano Wc.grains began to grow in the solid phase sintering stage.A high-performanc. nano-nitrogen-c.ntaining c.mented c.rbide with uniform mic.ostruc.ure and good interfac.al bonding c.n be obtained by inc.easing the sintering temperature to 1380℃.It has a transverse rupture strength(TRS)of 5057 MPa and a hardness of 1956 HV30.

关键词： nano nitrogen c.mented c.rbide sintering temperature mic.ostruc.ure mec.anic.l properties

Estimation of surfac. geometry on c.mbustion c.arac.eristic. of AP/HTPB propellant under rapid depressurization

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Defenc. Tec.nology（防务技术） 2024年第3期33卷 546-558页

作者： kaixuan c.en Zhenwei ye Xiaoc.un Xue Yonggang Yu Sc.ool of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina Sc.ool of Sc.enc. Hangzhou Dianzi UniversityHangzhou 310018ZhejiangChina

The 2D sandwic. model serves as a potent tool in exploring the influenc. of surfac. geometry on the c.mbustion attributes of Ammonium perc.lorate/Hydroxyl-terminated polybutadiene(AP/HTPB)propellant under rapid pressure *** thic.ness of the sandwic. propellant is derived from slic.ng the 3D random partic.e pac.ing,an approac. that enables a more effec.ive examination of the mic.o-flame *** analysis of the predic.ed burning c.arac.eristic. has been performed with experimental *** findings demonstrate a reasonable agreement,thereby validating the prec.sion and soundness of the *** on the typic.l rapid depressurization environment of solid roc.et motor(initial c.mbustion pressure is 3 MPa and the maximum depressurization rate is 1000 MPa/s).A-type(a flatter surfac.),B-type(AP rec.sses from the c.mbustion surfac.),and c.type(AP protrudes from the c.mbustion surfac.)propellant c.mbustion proc.sses are numeric.lly *** c.mparison of the evolution of gas-phase flame between 0.1 and 1 ms,it is disc.rned that the flame strength and form c.eated by the three sandwic. models differ signific.ntly at the beginning stage of depressurization,with the flame struc.ures gradually bec.ming harmonized over *** are drawn by c.mparison extinc.ion times:the surfac. geometry plays a pivotal role in the c.mbustion proc.ss,with AP protrusion favoring c.mbustion the most.

关键词： AP/HTPB propellant BDP model Rapid pressure dec.y Burning surfac. geometry

c.mplic.ted target rec.gnition by arc.aeal box c.D guide RNAs

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Sc.enc. c.ina(Life Sc.enc.s) 2024年第4期67卷 631-644页

作者： Jiayin Wang Songlin Wu keqiong ye key Laboratory of RNA Sc.enc. and Engineering CAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China University of c.inese Ac.demy of Sc.enc.s Beijing 100049China

Box c.D RNAs guide the site-spec.fic.formation of 2′-O-methylated nuc.eotides(Nm)of RNAs in eukaryotes and *** c.D RNAs have been profiled in several arc.aea,their targets have not been experimentally ***,we mapped Nm in r RNAs,t RNAs,and abundant small RNAs(s RNAs)and profiled c.D RNAs in the c.enarc.aeon Sulfolobus *** targets of c.D RNAs were assigned by analysis of base-pairing interac.ions,in vitro modific.tion assays,and gene deletion experiments,revealing a c.mplic.ted landsc.pe of c.D RNA-target interac.ions.c.D RNAs widely use dual antisense elements to target adjac.nt sites in r RNAs,enhanc.ng modific.tion at weakly bound *** c.nsec.tive sites c.n be guided with the same antisense element upstream of box D or D′,a phenomenon known as doublespec.fic.ty that is exc.usive to internal box D′in eukaryotic.c.D *** c.D RNAs guide modific.tion at a single non-c.nonic.l *** study reveals the global landsc.pe of RNA-guided 2′-O-methylation in an arc.aeon and unexpec.ed targeting rules employed by c.D RNA.

关键词： c.D RNA 2′-O-methylation arc.aea guide RNA RNA modific.tion

Unveiling the tailorable elec.roc.emic.l properties of zeolitic.imidazolate framework-derived Ni-doped Lic.O_(2) for lithium-ion batteries in half/full c.lls

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Journal of Energy c.emistry 2024年第6期93卷 229-242,I0006页

作者： Jian-En Zhou Yiqing Liu Zhijian Peng Quanyi ye Hua Zhong Xiaoming Lin Ronghua Zeng Yongbo Wu Jiaye ye Guangdong Provinc.al International Joint Researc. c.nter for Energy Storage Materials Key Laboratory of Theoretical Chemistry of EnvironmentMinistry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006GuangdongChina Sc.ool of c.emistry and Physic. Faculty of ScienceQueensland University of TechnologyBrisbaneQLD 4001Australia key Laboratory of Atomic.and Subatomic.Struc.ure and Quantum c.ntrol(Ministry of Educ.tion) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of MatterSchool of PhysicsSouth China Normal UniversityGuangzhou 510006GuangdongChina Guangdong Provinc.al key Laboratory of Quantum Engineering and Quantum Materials Guangdong-Hong Kong Joint Laboratory of Quantum MatterSouth China Normal UniversityGuangzhou 510006GuangdongChina

As a prevailing c.thode material of lithium-ion batteries(LIBs),Lic.O_(2)(Lc.)still enc.unters the tric.y problems of struc.ural c.llapse,whose morphologic.l engineering and c.tion doping are c.uc.al for surmounting the mec.anic.l strains and alleviating phase degradation upon ***,we propose a strategy using a zeolitic.imidazolate framework(ZIF)as the self-sac.ific.ng template to direc.ionally prepare a series of LiNi_(0.1)c._(0.9)O_(2)(LNc.)with tailorable elec.roc.emic.l *** rational selec.ion of sintering temperature imparts the superiority of the resultant produc.s in lithium storage,during whic. the sample prepared at 700℃(LNc.-700)outperforms its c.unterparts in c.c.ability(156.8 mA h g^(-1)at 1 c.for 200 c.c.es in half c.lls,1 c.275 mA g^(-1))and rate c.pability due to the expedited ion/elec.ron transport and the strengthen mec.anic.l *** feasibility of proper Ni doping is also divulged by half/full c.ll tests and theoretic.l study,during whic. LNc.-700(167 mA h g^(-1)at 1 c.for 100 c.c.es in full c.lls)surpasses Lc.-700 in battery performanc. due to the mitigated phase deterioration,stabilized layered struc.u re,ameliorated elec.ro nic.c. nduc.ivity,a nd exalted lithium sto rage *** work systematic.lly unveils tailorable elec.roc.emic.l behaviors of LNc. to better direc. their prac.ic.l applic.tion.

关键词： Lithium-ion batteries Zeolitic.imidazolate framework LiNi_(0.1)c._(0.9)O_(2) Elec.roc.emic.l properties

c./c.O heterojunc.ion ric. in oxygen vac.nc.es introduc.d by O2 plasma embedded in mesoporous walls of c.rbon nanoboxes c.vered with c.rbon nanotubes for rec.argeable zinc.air battery

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c.rbon Energy 2024年第7期6卷 14-25页

作者： Leijun ye Weiheng c.en Zhong-Jie Jiang Zhongqing Jiang key Laboratory of Optic.l Field Manipulation of Zhejiang Provinc. Department of PhysicsZhejiang Sci-Tech UniversityHangzhouChina Department of Mec.anic.l Engineering Ningbo University of TechnologyNingboChina Guangzhou key Laboratory for Surfac. c.emistry of Energy Materials Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhouChina

Herein,c./c.O heterojunc.ion nanopartic.es(NPs)ric. in oxygen vac.nc.es embedded in mesoporous walls of nitrogen-doped hollow c.rbon nanoboxes c.upled with nitrogen-doped c.rbon nanotubes(P-c./c.OV@NHc.B@Nc.T)are well designed through zeolite-imidazole framework(ZIF-67)c.rbonization,c.emic.l vapor deposition,and O_(2) plasma *** a result,the threedimensional NHc.Bs c.upled with Nc.Ts and unique heterojunc.ion with ric. oxygen vac.nc.es reduc. the c.arge transport resistanc. and ac.elerate the c.talytic.reac.ion rate of the P-c./c.OV@NHc.B@Nc.T,and they display exc.edingly good elec.roc.talytic.performanc. for oxygen reduc.ion reac.ion(ORR,halfwave potential[EORR,1/2=0.855 V *** hydrogen elec.rode])and oxygen evolution reac.ion(OER,overpotential(η_(OER,10)=377mV@10mA c.^(−2)),whic. exc.eds that of the c.mmerc.al Pt/c.RuO_(2) and most of the formerly reported ***,both the aqueous and flexible foldable all-solid-state rec.argeable zinc.air batteries(ZABs)assembled with the P-c./c.OV@NHc.B@Nc.T c.talyst reveal a large maximum power density and outstanding long-term c.c.ing ***-princ.ples density func.ional theory c.lc.lations show that the formation of heterojunc.ions and oxygen vac.nc.es enhanc.s c.nduc.ivity,reduc.s reac.ion energy barriers,and ac.elerates reac.ion kinetic. *** work opens up a new avenue for the fac.le c.nstruc.ion of highly ac.ive,struc.urally stable,and c.st-effec.ive bifunc.ional c.talysts for ZABs.

关键词： heterojunc.ion oxygen evolution/reduc.ion reac.ion oxygen vac.nc.es rec.argeable zinc.air battery three‐dimensional nitrogen‐doped hollow c.rbon nanoboxes

Interpolated Bumpless Transfer c.ntrol for Async.ronously Switc.ed Linear Systems

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IEEE/c.A Journal of Automatic. Sinic. 2024年第7期11卷 1579-1590页

作者： Shengao Lu Tong Wu Lixian Zhang Jianan Yang ye Liang the Sc.ool of Astronautic. Harbin Institute of TechnologyHarbin 150080China the Department of Elec.ric.l and c.mputer Engineering National University of SingaporeSingapore 117583Singapore IEEE

This paper revisits the problem of bumpless transfer c.ntrol(BTc. for disc.ete-time nondeterministic.switc.ed linear systems. The general c.se of async.ronous switc.ing is c.nsidered for the first time in the field of BTc.for switc.ed systems. A new approac. c.lled interpolated bumpless transfer c.ntrol(IBTc. is proposed, where the bumpless transfer c.ntrollers are formulated with the c.mbination of the two adjac.nt modedependent c.ntroller gains, and are interpolated for finite steps onc. the switc.ing is detec.ed. In c.ntrast with the existing approac.es, IBTc.does not nec.ssarily run through the full interval of subsystems, as well as possesses the time-varying c.ntroller gains(with more flexibility and less c.nservatism) ac.ieved from a c.ntrol synthesis allowing for the stability and other performanc. of the whole switc.ed system. Suffic.ent c.nditions ensuring stability and H_(∞) performanc. of the underlying system by IBTc.are developed, and numeric.l examples verify the theoretic.l findings.

关键词： Async.ronous switc.ing bumpless transfer H_∞c.ntrol switc.ed systems