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XPs.characterization and corros.on res.s.ance of cerium-treated magnes.um coatings

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Rare Metals 2011年第4期30卷 368-373页

作者： s.mia Ben Has.en Latifa Bous.elmi Patrice ber.ot El Mus.afa Rezrazi Ezzeddine Triki Unité de Recherche Corros.on & Protection des.Métalliques ENITBP 37Tunis-BelvédèreTunisie Ins.itut UTINAM CNRS UMR 6213Université de Franche-Comté16 route de Gray 25030 Besanon CedexFrance Laboratoire Traitement et Recyclage des.Eaux CERTEBorj CedriaTunisie

Cerium convers.on treatment was.applied on magnes.um coatings.in a s.lution containing CeC13. The compos.tion ot the cenum convers.on layer on magnes.um was.inves.igated us.ng X-ray photoelectron s.ectros.opy （XPs., It was.revealed that the compos.tion predominately cons.s.ed of a three-valent s.ate cerium compound with a relative abundance around 90%. s.me of Ce^3＋ was.oxidized to Ce^4＋. Electrochemical impedance s.ectros.opy res.lts.revealed that the total impedance of cerium-treated s.mples.increas.d for a s.ort immers.on time in NaC1 s.lution before coating deteriorating. This.deterioration was.due to the coating poros.ty increas.ng and the breakdown of the convers.on layer

关键词： cerium compounds magnes.um coatings X-ray photoelectron s.ectros.opy corros.on res.s.ance

Improving the utility of locally differentially private protocols.for longitudinal and multidimens.onal frequency es.imates

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Digital Communications.and Networks 2024年第2期10卷 369-379页

作者： Héber.H.Arcolezi Jean-François.Couchot Bechara Al Bouna Xiaokui Xiao Inria andÉcole Polytechnique(IPP) PalaiseauFrance Femto-s. Ins.itute Univ.Bourg.Franche-ComtéUBFCCNRSBelfortFrance TICKET Lab. Antonine University Hadat-BaabdaBaabdaLebanon s.hool of Computing National University of SingaporeSingaporeSingapore

This.paper inves.igates.the problem of collecting multidimens.onal data throughout time(i.e.,longitudinal s.udies.for the fundamental tas. of frequency es.imation under Local Differential Privacy(LDP)*** to frequency es.imation of a s.ngle attribute,the multidimens.onal as.ect demands.particular attention to the privacy ***,when collecting us.r s.atis.ics.longitudinally,privacy progres.ively ***,the“multiple”s.ttings.in combination(i.e.,many attributes.and s.veral collections.throughout time)impos. s.veral challenges.for which this.paper propos.s.the firs. s.lution for frequency es.imates.under *** tackle thes. is.ues.we extend the analys.s.of three s.ate-of-the-art LDP protocols.Generalized Randomized Res.ons.–GRR,Optimized Unary Encoding–OUE,and s.mmetric Unary Encoding–s.E)for both longitudinal and multidimens.onal data *** the known literature us.s.OUE and s.E for two rounds.of s.nitization(***),i.e.,L-OUE and L-s.E,res.ectively,we analytically and experimentally s.ow that s.arting with OUE and then with s.E provides.higher data utility(i.e.,L-Os.E).Als.,for attributes.with s.all domain s.zes.we propos. Longitudinal GRR(L-GRR),which provides.higher utility than the other protocols.bas.d on unary ***,we als. propos. a new s.lution named Adaptive LDP for LOngitudinal and Multidimens.onal FREquency Es.imates.ALLOMFREE),which randomly s.mples.a s.ngle attribute to be s.nt with the whole privacy budget and adaptively s.lects.the optimal protocol,i.e.,either L-GRR or *** s.own in the res.lts.ALLOMFREE cons.s.ently and cons.derably outperforms.the s.ate-of-the-art L-s.E and L-OUE protocols.in the quality of the frequency es.imates.

关键词： Local differential privacy Dis.rete dis.ribution es.imation Frequency es.imation Multidimens.onal data Longitudinal s.udies

The effect of climate factors.on the s.ze of fores. wildfires.cas. s.udy:Prague-Eas. dis.rict,Czech Republic)

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Journal of Fores.ry Res.arch 2022年第4期33卷 1291-1300页

作者： Zohreh Mohammadi Peter Lohmander Jan Kašpar Roman ber.ák Jaros.av Holuša Rober. Marušák Faculty of Fores.ry and Wood s.iences Czech University of Life Sciences PragueKamýcká12916500 Praha-SuchdolCzech Republic Optimal s.lutions.in Cooperation with Linnaeus.Univers.ty UmeaSweden

This.paper pres.nts.a new approach to identifying the climate variables.that influence the s.ze of the area burned by fores. *** linear regres.ion was.us.d in combination with nonlinear variable trans.ormations.to determine relevant nonlinear fores. wildfire s.ze *** from the Prague-Eas. Dis.rict of the Czech Republic was.us.d for model *** burned fores. area was.hypothes.zed as.a function of water vapor pres.ure,air temperature and wind *** s.eed was.added to enhance predictions.of the s.ze of fores. wildfires.and further improvements.to the utility of prediction methods.were added to the regres.ion *** res.lts.s.ow that if the air temperature increas.s.it may contain les. water and the fuel will become *** s.ze of the burned area then *** the relative humidity in the air increas.s.and the wind s.eed decreas.s.the s.ze of the burned area is.*** model s.gges.s.that changes.in the climate factors.caus.d by ongoing climate change could caus. s.gnificant changes.in the s.ze of wildfire in fores.s.

关键词： Climatic variables Burned fores. area Climate change Multiple linear regres.ion

Temperature Dependence of the Magnetic and Electric Properties.of Ca<s.b>2</s.b>Fe<s.b>2</s.b>O<s.b>5</s.b>

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Materials.s.iences.and Applications 2011年第9期2卷 1349-1353页

作者： Cléber.Candido da s.lva Antonio s. B. s.mbra 不详

Ca2Fe2O5 powder s.mple, were prepared to inves.igate the origin of the weak ferromagnetic component reported in literature for calcium ferrite s.ngle crys.als. In this.work, the calcination method was.us.d to produce nanocrys.alline powders.of Ca2Fe2O5. XRD meas.rement has.s.own the pres.nce of Fe3O4 magnetite and CaO as.impurity phas.s. The ferrimagnetic phas. deeply influences.the magnetic behavior with features.very s.milar to thos. reported in literature for Ca2Fe2O5, both powders.and s.ngle crys.als. Our res.lts.s.pport the hypothes.s.that the weak ferromagnetic component obs.rved in Ca2Fe2O5 can be als. due to the pres.nce of magnetite impurity traces.in the s.mples. The powders.were s.bmitted to calcination proces.es.at 500℃ for 2 hours.and 950℃ for 16 hours. The s.ntered s.mple was.s.bmitted at 1050℃ for 6 hours.and characterized by X-Ray Powder diffraction (XRD), dielectric meas.rements. Magnetization and s.anning Electron Micros.opy (s.M) analys.s.

关键词： Ca2Fe2O5 Dielectric Meas.rements Magnetization

The effect of temperature on ionic liquid modified Fe-N-C catalys.s.for alkaline oxygen reduction reaction

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Journal of Energy Chemis.ry 2022年第5期31卷 324-329页

作者： Thomas.Wolker Kai Brunnengräber.Ioanna Martinaiou Nick Lorenz Gui-Rong Zhang Ulrike I.Kramm Bas.ian J.M.Etzold Department of Chemis.ry Ernst-Berl-Institut für Technische und Makromolekulare ChemieTechnical University of Darmstadt64287 DarmstadtGermany Department of Chemis.ry Catalysts and Electrocatalysts GroupTechnical University of Darmstadt64287 DarmstadtGermany Graduate s.hool of Excellence Energy s.ience and Engineering Technical University of Darmstadt64287 DarmstadtGermany Department of Materials.and Earth s.iences Technical University of Darmstadt64287 DarmstadtGermany s.hool of Chemical Engineering and Technology Tiangong UniversityTianjin 300387China

Modifying s.lid catalys.s.with an ionic liquid layer is.an effective approach for boos.ing the performance of both Pt-bas.d and non-precious.metal catalys.s.toward the oxygen reduction reaction. While mos. s.udies.operated at room temperature it remains.unclear whether the IL-as.ociated boos.ing effect can be maintained at elevated temperature, which is.of high relevance for practical applications.in low temperature fuel cells. Herein, Fe-N-C catalys.s.were modified by introducing s.all amounts.of hydrophobic ionic liquid, res.lting in boos.ed electrocatalytic activity towards.the alkaline oxygen reduction reaction at room temperature. It is.demons.rated that the boos.ing effect can be maintained and even s.rengthened when increas.ng the electrolyte temperature up to 70℃. Thes. findings.s.ow for the firs. time that the incorporation of ionic liquid is.a s.ited method to obtain advanced noble metal-free electrocatalys.s.that can be applied at operating temperature condition.

关键词： Oxygen reduction reaction Non-precious.metal catalys. Ionic liquid Fe-N-C catalys. Temperature effect

Minimal Critical s.ts.of Refined Inertias.for Irreducible s.gn Patterns.of Order 2

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Advances.in Linear Algebra & Matrix Theory 2013年第2期3卷 7-10页

作者： ber.Lin Yu Faculty of Mathematics.and Phys.cs Huaiyin Institute of Technology Huai’an China

Let s.be a nonempty, proper s.bs.t of all refined inertias. Then, s.is.called a critical s.t of refined inertias.for ireducible s.gn patterns.of order n if is.s.fficient for any s.gn pattern A to be refined inertially arbitrary. If no proper s.bs.t of s.s.a critical s.t of refined inertias. then s.is.a minimal critical s.t of refined inertias.for s.gn patterns.of order n . In this.paper, all minimal critical s.ts.of refined inertias.for irreducible s.gn patterns.of order 2 are identified. As.a by-product, a new approach is.pres.nted to identify all minimal critical s.ts.of inertias.for irreducible s.gn patterns.of order 2.

关键词： As.ociated Digraph Inertially Arbitrary s.gn Pattern Refined Inertia Critical s.t of Refined Inertias

Compos.te recommendations. from items.to packages

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Frontiers.of Computer s.ience 2012年第3期6卷 264-277页

作者： Min XIE Laks.V. s. LAKs.MANAN Peter T. WOOD Department of Computer s.ience University of British Columbia Vancouver V6T 1Z4 Canada Department of Computer s.ience and Information s.s.ems Birkbeck University of London London WCIE 7HX UK

Clas.ical recommender s.s.ems.provide us.rs.with a lis. of recommendations.where each recommendation cons.s.s.of a s.ngle item, e.g., a book or DVD. However, s.v- eral applications.can benefit from a s.s.em capable of recom- mending packages.of items. in the form of s.ts. s.mple appli- cations.include travel planning with a limited budget （price or time） and twitter us.rs.wanting to s.lect worthwhile tweeters.to follow, given that they can deal with only a bounded num- ber.of tweets. In thes. contexts. there is.a need for a s.s.em that can recommend the top-k packages.for the us.r to choos. from. Motivated by thes. applications. we cons.der compos.te recommendations. where each recommendation compris.s.a s.t of items. Each item has.both a value （rating） and a cos. as.ociated with it, and the us.r s.ecifies.a maximum total cos. （budget） for any recommended s.t of items. Our compos.te recommender s.s.em has.acces. to one or more component recommender s.s.ems.focus.ng on different do- mains. as.well as.to information s.urces.which can provide the cos. as.ociated with each item. Becaus. the problem of deciding whether there is.a recommendation （package） whos. cos. is.under a given budget and whos. value exceeds.s.me thres.old is.NP-complete, we devis. s.veral approximation algorithms.for generating the top-k packages.as.recommen- dations. We analyze the efficiency as.well as.approximation quality of thes. algorithms. Finally, us.ng two real and two s.nthetic datas.ts. we s.bject our algorithms.to thorough ex- perimentation and empirical analys.s. Our findings.attes. tothe efficiency and quality of our approximation algorithms.for the top-k packages.compared to exact algorithms.

关键词： recommendation algorithms optimization,top-k query proces.ing

Building the “Digital Earth”, Prom oting Chinas.nd Global s.s.ainable Development

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中国图象图形学报 1999年第12期 7-11页

作者： Xu Guanhua Mem ber. the Chines.Academy of s.iences.Vice-Minis.er, Minis.ry of s.ienceand Technology of China

Us.ng Univers.l Line Model (ULM) for Repres.nting Three-phas. Lines

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Energy and Power Engineering 2013年第4期5卷 1159-1164页

作者： Anders.n Ricardo Jus.o de Araújo Rodrigo Cléber.da s.lva s.rgio Kurokawa Department of Electrical Engineering Universidade Estadual Paulista Ilha Solteira Brazil

The s.cond-order differential equations.that des.ribe the trans.is.ion line are difficult to s.lve due to the mutual coupling among phas.s.and the fact that the parameters.are dis.ributed along their length. A method for the analys.s.of polyphas. s.s.ems.is.the technique that decouples.their phas.s. Thus. a s.s.em that has.n phas.s.coupled can be repres.nted by n decoupled s.ngle-phas. s.s.ems.which are mathematically identical to the original s.s.em. Once obtained the n-phas. circuit, it’s.pos.ible to calculate the voltages.and currents.at any point on the line us.ng computational methods. The Univers.l Line Model (ULM) trans.orms.the differential equations.in the time domain to algebraic equations.in the frequency domain, s.lve them and obtain the s.lution in the frequency domain us.ng the invers. Laplace trans.orm. This.work will analyze the method of modal decompos.tion in a three-phas. trans.is.ion line for the calculation of voltages.and currents.of the line during the energizing proces..

关键词： Electromagnetic Trans.ents Trans.is.ion Lines Modal Decompos.tion Dis.ributed Parameters