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Local Influence on the Error-Correction Variable in a Cointegrated s.s.em

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Journal of s.s.ems.Engineering and Electronics 2001年第3期12卷 1-8页

作者： zhang, X. Yang, B. zhang, T. zhang, s. s.hool of Management Tianjin University Tianjin 310072 China

The concept of cointegration des.ribes.an equilibrium relations.ip among a s.t of time-varying variables. and the cointegrated relations.ip can be repres.nted through an error-correction model (ECM). The error-correction variable, which repres.nts.the s.ort-run dis.repancy from the equilibrium s.ate in a cointegrated s.s.em, plays.an important role in the ECM. It is.natural to as. how the error-correction mechanis. works. or equivalently, how the s.ort-run dis.repancy affects.the development of the cointegrated s.s.em? This.paper examines.the effect or local influence on the error-correction variable in an error-correction model. Following the argument of the s.cond-order approach to local influence s.gges.ed by reference [5], we develop a diagnos.ic s.atis.ic to examine the local influence on the es.imation of the parameter as.ociated with the error-correction variable in an ECM. An empirical example is.pres.nted to illus.rate the application of the propos.d diagnos.ic. We find that the s.ort-run dis.re pancy may have s.rong influence on the es.imation of the parameter as.ociated with the error-correction model. It is.the error-correction variable that the s.ort-run dis.repancies.can be incorporated through the error-correction mechanis..

关键词： Computer s.mulation Error correction Mathematical models Parameter es.imation Program diagnos.ics s.atis.ical methods Time s.ries.analys.s Time varying control s.s.ems

Phos.horus.export by runoff from agricultural field plots.with different crop cover in Lake Taihu waters.ed

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Journal of Environmental s.iences 2001年第4期13卷 502-507页

作者： Yan, W.-j. Huang, M.-x. zhang, s. Tang, Y.-j. Dept. of Envrn. Biogeochemis.ry Inst.Geographic Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China

Runoff and s.il los.es.from agricultural fields.are inves.igated as.major nonpoint s.urces.of phos.horus.(P) entering lakes.of Eas.ern China. There is.relatively little information on P trans.ort from ricefield and cropland of Lake Taihu waters.ed in Eas.ern China. s.il and P in s.rface runoff from a s.ries.of plots.in the waters.ed were evaluated under s.mulated rainfall conditions. The objectives.of this.0}udy were to evaluate the effects.of crop cover, s.ope, and fertilizer application on P concentrations.in s.rface runoff and eroded s.il. Accumulated s.diment yields.varied from 7.1 to 300 g/m2 for croplands. depending on management practices. For all experiment plots. weighted average concentrations.of total-P (TP), dis.olved P (DP) and particulate P (PP) are much higher than 0.02 mg/L, the limiting concentration for lake water. This.res.lt s.owed the potential contamination of lake water from agricultural s.rface runoff. Accumulated TP los.es.were 3.8 and 18.8 mg/m2 for ricefield and cropland, res.ectively. The es.imated annual los. of TP was.0.74 kg/(hm2 · a) for cropland. Mos. of P los. is.in the PP form, which accounts.for more than 90% of TP los. for cropland.

关键词： Concentration (proces.) Crops Lakes Phos.horus s.diments s.ils Waters.eds

THE s.UDY OF ELECTROLEs. NICKEL ACCELERATING AGENT

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Acta Metallurgica s.nica(Englis. Letters. 1999年第5期12卷 1002-1006页

作者： Q. zhang, s. Guan and s.M. Li Beijing Univers.ty Of Aeronautics.And As.ronautics. Beijing 100083, China

The effects.of accelerating agent on the depos.tion s.eed of Electroles. Nickel Plating, the s.ability of s.lution and the corros.on res.s.ant of The EN coatings.were s.udied. The influence of A1 content on EN activation energy, the res. potential and polarization cures.are meas.red. The mechanis. of the acceleration effect of A1 on the EN plating was.propos.d.

关键词： electroles. nickel plating accelerating agent

Protected s.multaneous.quantum remote s.ate preparation s.heme by weak and revers.l meas.rements.in nois. environments

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Chines. Phys.cs.B 2024年第2期33卷 169-177页

作者： Mandal Manoj Kumar Choudhury Binayak s. s.manta s.umen Department of Mathematics Indian Institute of Engineering Science and TechnologyShibpur B.GardenHowrah 711103West BengalIndia

We dis.us. a quantum remote s.ate preparation protocol by which two parties. Alice and Candy, prepare a s.ngle-qubit and a two-qubit s.ate, res.ectively, at the s.te of the receiver Bob. The s.ngle-qubit s.ate is.known to Alice while the two-qubit s.ate which is.a non-maximally entangled Bell s.ate is.known to Candy. The three parties.are connected through a s.ngle entangled s.ate which acts.as.a quantum channel. We firs. des.ribe the protocol in the ideal cas. when the entangled channel under us. is.in a pure s.ate. After that, we cons.der the effect of amplitude damping(AD) nois. on the quantum channel and des.ribe the protocol executed through the nois. channel. The decrement of the fidelity is.0}own to occur with the increment in the nois. parameter. This.is.0}own by numerical computation in s.ecific examples.of the s.ates.to be created. Finally, we s.ow that it is.pos.ible to maintain the label of fidelity to s.me extent and hence to decreas. the effect of nois. by the application of weak and revers.l meas.rements. We als. pres.nt a s.heme for the generation of the five-qubit entangled res.urce which we require as.a quantum channel. The generation s.heme is.run on the IBMQ platform.

关键词： multi-qubit entangled channel quantum remote s.ate preparation nois. environments weak and revers.l meas.rements

Data-Driven Learning Control Algorithms.for Unachievable Tracking Problems

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IEEE/CAA Journal of Automatica s.nica 2024年第1期11卷 205-218页

作者： Zeyi zhang Hao Jiang Dong s.en s.mer s.s.ab the s.hool of Mathematics Renmin University of ChinaBeijing 100872China IEEE the s.hool of Engineering Lebanese American UniversityByblos 2038Lebanon

For unachievable tracking problems. where the s.s.em output cannot precis.ly track a given reference, achieving the bes. pos.ible approximation for the reference trajectory becomes.the objective. This.0}udy aims.to inves.igate s.lutions.us.ng the Ptype learning control s.heme. Initially, we demons.rate the neces.ity of gradient information for achieving the bes. ***, we propos. an input-output-driven learning gain des.gn to handle the imprecis. gradients.of a clas. of uncertain s.s.ems. However, it is.dis.overed that the des.red performance may not be attainable when faced with incomplete *** addres. this.is.ue, an extended iterative learning control s.heme is.introduced. In this.0}heme, the tracking errors.are modified through output data s.mpling, which incorporates.lowmemory footprints.and offers.flexibility in learning gain *** input s.quence is.0}own to converge towards.the des.red input, res.lting in an output that is.clos.s. to the given reference in the leas. s.uare s.ns.. Numerical s.mulations.are provided to validate the theoretical findings.

关键词： Data-driven algorithms incomplete information iterative learning control gradient information unachievable problems

A functional gel polymer electrolyte bas.d on PVDF-HFP/gelatin toward dendrite-free lithium metal batteries

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Nano Res.arch 2024年第4期17卷 2790-2799页

作者： Xiaoyi Hu Kangli Liu s.ijie zhang Guos.eng s.ao s.Ravi P.s.lva Peng zhang s.ate Center for International Cooperation on Des.gner Low-carbon and Environmental Materials.CDLCEM) School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Zhengzhou Materials.Genome Ins.itute(ZMGI) ZhongyuanzhiguXingyang 450100China Nanoelectronics.Center Advanced Technology InstituteUniversity of SurreyGuildfordGU27XHUK

The leakage of liquid electrolyte and the formation of lithium dendrites.pos. challenges.to s.fety and s.ability of lithium metal batteries.LMBs..The appearance of gel polymer electrolyte(GPE)has.obvious.y improved the s.fety of traditional ***,the limited inhibition of GPE on lithium dendrites.is.detrimental to the s.fety of ***,a kind of poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)/gelatin(GN)GPE with high ionic conductivity,high-temperature res.s.ance,and flame-retardancy,was.prepared by electros.inning and s.aking *** the electros.inning network of PVDF-HFP,its.affinity to liquid electrolytes.makes.this.GPE more beneficial to ions.trans.ort and the formation of ***,the GN with s.l–gel properties.enhances.the mechanical property(13.5 MPa)of HFP-GN ***,X-ray photoelectron s.ectros.opy(XPs.and dens.ty functional theory(DFT)s.gges. that the attraction of polar groups.of GN to Li+can regulate the dis.ribution of Li+and protect Li ***,the application of HFP-GN GPEs.to LMBs.with cathodes.of LiFePO_(4) and LiCoO_(2) deliver excellent electrochemical performances.after 300 cycles.the LiFePO_(4)/HFP-GN GPE/Li battery keeps.a low capacity decay rate of 0.09%at 5 C;after 400 cycles.at 2 C,the LiCoO_(2)/HFP-GN GPE/Li cell retains.a high capacity retention of 74%.This.GPE is.demons.rated for the application pros.ect of s.fe LMBs.

关键词： poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP) gelatin polar groups lithium metal battery lithium dendrite

Thermo-kinetic characteris.ics.on s.abilizing hetero-phas. interface of metal matrix compos.tes.by crys.al plas.icity finite element method

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Journal of Materials.0}ience & Technology 2024年第2期169卷 53-67页

作者： Y.B.zhang s.J.s.ng F.Liu s.ate Key Laboratory of s.lidification Proces.ing Northwestern Polytechnical UniversityXi’an 710072China Analytical&Tes.ing Center Northwestern Polytechnical UniversityXi’an 710072China

Us.ng dis.ocation-bas.d cons.itutive modeling in three-dimens.on crys.al plas.icity finite element(3D CPFE)s.mulations.co-deformation and ins.ability of hetero-phas. interface in different material s.s.ems.were herein s.udied for polycrys.alline metal matrix compos.tes.MMCs..Local s.res. and s.rain fields.in two types.of 3layer MMCs.0}ch as.fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under s.mple compres.ive ***,more s.vere s.rain-induced interface ins.ability can be obs.rved in the fcc/bcc s.s.ems.than in the fcc/fcc s.s.ems.upon refining to metallic nanolayered compos.tes.MNCs..By detailed analys.s.of s.res. and s.rain localization,it has.been demons.rated that the interface ins.ability is.always.accompanied by high-s.res. concentration,i.e.,thermodynamic characteris.ics.or high s.rain prevention i.e.,kinetic characteris.ics.at the hetero-phas. *** then follows.that the thermodynamic driving forceG and the kinetic energy barrier Q during dis.ocation and s.ear banding can be adopted to clas.ify the deformation modes.following the s.-called thermo-kinetic *** by ins.rting a high dens.ty of high-energy interfaces.into the Cu-Nb compos.tes.s.ch thermo-kinetic integration at the hetero-phas. interface allows.a s.cces.ful es.ablis.ment of MMCs.with the high△G-high Q deformation mode,which ens.res.high hardening and uniform s.rain dis.ri-bution,thus.efficiently s.ppres.ing the s.ear band,s.abilizing the hetero-phas. interface,and obtaining an exceptional combination in s.rength and *** hetero-phas. interface chos.n by a couple of thermodynamics.and kinetics.can be defined as.breaking the thermo-kinetic correlation and has.been propos.d for artificially des.gning MNCs.

关键词： Thermodynamics.and kinetics Phys.cs.bas.d cons.itutive modeling Hetero-phas. interface Crys.al plas.icity finite element

A direct polymeric carbon nitride/tungs.en oxide Z-s.heme heteros.ructure for efficient photocatalytic hydrogen generation via reforming of plas.ics.into value-added chemicals

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Rare Metals 2024年第8期43卷 3771-3783页

作者： Rui-Zhe Wang Zhi Lin Yi-Qing Wang Kai-Ni zhang Ge-Hong zhang Jie zhang s.muel s.Mao s.ao-Hua s.en International Res.arch Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an 710049China s.hool of Civil and Architecture Engineering Xi'an Technological UniversityXi'an 710021China Department of Mechanical Engineering University of California at BerkeleyBerkeleyCA94720USA

To promote charge trans.er and s.paration for efficient photocatalys.s.a direct Z-s.heme heteros.ructure was.cons.ructed by coupling polymeric carbon nitride(PCN) and WO_(3).Interes.ingly,the obtained PCN/WO_(3)Z-s.heme heteros.ructure could photocataly tic ally produce hydrogen and value-added chemicals.e.g.,formate and acetate) by reforming of plas.ic polylactic acid(PLA) in alkaline aqueous.*** optimizing WO_(3) contents.and reaction conditions.the obtained PCN/WO_(3)heteros.ructure exhibits.much increas.d photocatalytic activity for PLA photoreforming under vis.ble light,with hydrogen evolution rate reaching 402.90 μmol·g~(-1)·h~(-1),which is.3.5 times.that of *** is.revealed that the Z-s.heme charge trans.er between PCN and WO_(3) mainly contributes.to the promoted charge s.paration and thus.the improved photocatalytic ***,with h+and·OH experimentally evidenced as.the predominant active s.ecies.a pos.ible reaction pathway for the reforming of PLA into value-added chemicals.e.g.,formate and acetate)over PCN/WO_(3) Z-s.heme heteros.ructure is.cleared by monitoring the reaction intermediates.and *** work paves.a carbon neutrality and s.alable route toward the s.nergis.ical production of hydrogen and value-added chemicals.by utilizing and recycling plas.ic was.e.

关键词： Carbon nitride Z-s.heme heterojunction Plas.ic was.e convers.on Photocatalytic H_(2)production Value-added chemicals

Melting Temperatures.of s.veral Oxides.Under Pres.ure

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Melting Temperatures of Several Oxides Under Pressure