简介：Arithmeticcodingisarelativelynewloss-lessdatacompressiontechniquethathasattractedmuchattentioninrecentyears.Weshowtheiterationofbit-levelarithmeticcodingcanbespecifiedbyacontinuousfunction.Theanalysisexpressionandsomepropertiesofthisfunctionarediscussed.Anapplicationofthefunctionisprovidedforexploringthesecurityofarithmeticcodeswhentheyareusedfordataencryption.

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简介：我们现在的新奇向量排列和分支减小方法为小点颠倒算法骑车最小化执行的数字。新方法被使用挑选指令多重数据(SIMD)平行复杂数据浮点的实现快Fourier变换(快速傅里叶变换)。运作的钟周期的数字能被使用我们的分支减小方法被使用我们的向量排列方法并且在1.1被3.5的一个平均因素减少，与常规实现相比。MPC7448的实验(著名SIMD减少了指令集计算处理器)证明我们的最佳的小点颠倒算法一致地在复杂数组操作每元素比二个周期拿少数。

简介：Variousindexstructureshaverecentlybeenproposedtofacilitatehigh-dimensionalKNNqueries,amongwhichthetechniquesofapproximatevectorpresentationandone-dimensional(1D)transformationcanbreakthecurseofdimensionality.Basedonthetwotechniquesabove,anovelhigh-dimensionalindexisproposed,calledBit-codeandDistancebasedindex(BD).BDisbasedonaspecialpartitioningstrategywhichisoptimizedforhigh-dimensionaldata.Bythedefinitionsofbitcodeandtransformationfunction,ahigh-dimensionalvectorcanbefirstapproximatelyrepresentedandthentransformedintoa1Dvector,thekeymanagedbyaB+-tree.AnewKNNsearchalgorithmisalsoproposedthatexploitsthebitcodeanddistancetoprunethesearchspacemoreeffectively.ResultsofextensiveexperimentsusingbothsyntheticandrealdatademonstratedthatBDout-performstheexistingindexstructuresforKNNsearchinhigh-dimensionalspaces.

简介：Reductionofmodulatorenergyconsumptionto10fJ∕bitisessentialforthesustainabledevelopmentofcommunicationsystems.Lumpedmodulatorsmightbeaviablesolutionifinstructedbyacompletetheorysystem.Here,wepresentacompleteanalyticalelectro-opticresponsetheory,energyconsumptionanalysis,andeyediagramsonabsolutescalesforlumpedmodulators.Consequentlythespeedlimitationisunderstoodandalleviatedbysingle-driveconfiguration,andcomprehensiveknowledgeintotheenergydependenceonstructuralparameterssignificantlyreducesenergyconsumption.Theresultsshowthatsiliconmodulationenergyaslowas80.8and21.5fJ∕bitcanbeachievedat28Gbdunder50and10Ωimpedancedrivers,respectively.A50Gbdmodulationisalsoshowntobepossible.Theanalyticalmodelscanbeextendedtolumpedmodulatorsonothermaterialplatformsandofferapromisingsolutiontothecurrentchallengesofmodulationenergyreduction.

简介：TheequilibriummolalitiesofIn3+inextractionreaction:In3+(aq)+3HOx(org)=In(Ox)3(org)+3H+(aq)weremeasuredationicstrengthsfrom0.13to2.54mol-kg-1intheaqueousphasecontainingNa2SO4asthesupportingelectrolyteandatconstantinitialmolalityofextractant,HOx,intheorganicphaseattemperaturesfrom278.15to308.15K,whereHOxandOxmean8-hydroxy-quinoliueanditsanion,respectively.ThestandardextractionconstantsK0atvarioustemperatureswereobtainedbytwomethodsproposedinourpreviouspaper.

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简介：Thispaperreportstwolanthanidecomplexesofformula（C9H7）Ln（C8H8）·（THF）2whereLnisProrNd,C9H7isindenyl,andC8H8iscyclooctatetraene（COT）.ThecomplexeswerepreparedbythereactionofLnCl3withK（C9H7）andK2（C8H8）inTHF.（C9H7）Pr（C8H8）·（THF）2crystallizesinTHFat-15℃inthemonoclinicspacegroupP21:withunitcelldimensionsa=8.446（0）,b=10.083（2）,c=13.407（3）,β=105.48（1）°,V=1100.43（35）3,Dc=1.52g/cm3andZ=2.ThefinalRvalueis0.033,Rwvalueis0.030,respectively.In（C9H7）Pr（C8H8）·（THF）2afive-memberedringcentroidofC9H7,theC8H8ringcentroidandthetwooxygenatomsfromthetwoTHFmoleculesformadistortedtetrahedralgeometryaroundthemetal.

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简介：一、填空题（每空1分，共25分）1．实验室里常用__________等仪器测物体的质量．若宇航员将一质量为2kg的矿石样本从月球带到地球上，它的质量是__________kg，物重是_______N．

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简介：ThedevelopmentoftheHalfWaveResonator(HWR010)isbasedontheChinaADSproject.TheHWR010operatesat162.5MHzandcanprovidemorethan0.78MVofacceleratingvoltagepercavityforprotonwithopt=0.10.ThegoaloftheRFpropertiesistogetalowerheatloadandahigheracceleratinggradient,whicharedeterminedbyahigherR/Q0andlowerpeaksurfacefields(Bpk/EaccandEpk/Eacc).InordertooptimizetheHWRgeometryparameters,CST-MWSisusedtoconducttheRFsimulation.TheoptimizedRFparametersareshowinTable1.

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简介：Thispaperreportsthattheetchingmorphologyofdislocationsin8°off-axis4H-SiCepilayerisobservedbyusingascanningelectronicmicroscope.Itisfoundthatdifferenttypesofdislocationscorrespondwithdifferentdensitiesandbasalplanedislcation(BPD)arrayandthreadingedgedislocation(TED)pileupgroupliealongsomecertaincrystaldirectionsintheepilayer.Itisconcludedthattheelasticenergyofthreadingscrewdislocations(TSDs)ishighestandTEDsislowestamongthesedislocations,sothedensityofTSDsislowerthanTEDs.TheBPDscanconverttoTEDsbutTSDscanonlypropagateintotheepilyerinspiteofthehigherelasticenergythanTEDs.ThereasonoftheformofBPDsarrayinepilayeristhatthebigstepalongthebasalplanecausedbyfacedefectsblockedtheupstreamatoms,andTEDspileupgroupisthatthedislocationsslideisblockedbydislocationgroupsinepilayer.

简介：Catalyticcombustionofpropane-airmixturewasinvestigated.Platinumcatalystsoveraflatstainlesssteelwithγ-aluminawashcoatwereemployed.Theemployedburnerhasthreecatalystssetparalleltothemixtureflow,spacedatanintervalof5,10and15mm.Bothexperimentandnumericalsimulationweremadeatinlettemperatureof553K,inletvelocityof3to7m/sandequivalenceratioof0.3to0.5.Inthenumericalsimulation,two-dimensional,steadystatemodelwasdevelopedtocalculatethetemperatureandspeciesconcentrationingas-phase.Inthismodel.chemicalreactiononthecatalystsurfaceandthatinthegasphasewereassumedtooccurinthree-steps.Thenumericalresultsshowgoodagreementwithexperimentalresults.Itwasfoundthatthepropertiesofthecatalyststronglyaffectthecatalystsurfacetemperature.Especially,thethermalconductivityofcatalysthasagreateffect,whiletheemissivityofcatalysthaslesseffect.

简介：ThefluorescenceemissionandX-raydiffractionofmagenesium8-hydroxyquinolinecomplex(Mgq2)havebeenmeasuredathighpressureupto14GPa.Ithasbeenfoundthatpressurecaninfluencetheemissiondramatically.Atrelativelowerpressure(lessthan2.5GPa)thefluorescenceofMgq2changesslightly,buttheemissiondropsquicklywithincreaseofthepressurewhenthepressuregetshigherthan2.5GPa.TheresultsofinsituenergydispersiveX-raydiffractionathighpressurewithsynchrotronradiationindicatethatthereisaphasetransitionatabout2.5-3GPaforMgq2crystal.2001ElsevierScienceB.V.Allrightsreserved.

简介：本文构造了一系列方程,由这些方程可以得到一年中任何一天、一天中任何一个时刻、从地球上任何纬度观察的太阳在天空中的位置。由这些方程出发,给出了太阳每年一次的8字形图的解释。这些方程还可以预测日出与日落时间。结合对8字形图的理解,本文证明了日出开始变早的时间为什么不是恰好在冬至时刻,而是在冬至以后的一段时间。在方程的构造中,模型假定地球环绕太阳运行的轨道是一个圆,且沿轨道匀速运动,利用日出的预测时间来评估由这个假设所引起的误差。

简介：Thedeuteronisalooselyboundstateoftwonucleons.Itisnaturaltoexpectotherboundstatescomposedoftwohadrons,thatis,hadronicmolecularstates[1].AftertheobservationbytheBelleCollaboration,theX(3872)wasrelatedtoalooselyboundstateofDˉDimmediatelyduetothefactthatitsmassisneartheDˉDthreshold.Recently,theBelleCollaborationannouncedtwochargedbottomonium-likestructuresZb(10610)andZb(10650)neartheBˉBandBˉBthresholds[2].TheanalysisoftheangulardistributionindicatedbothZb(10610)andZb(10650)favorIG(JP)=1+(1+).AstructureZc(3900)closetotheDˉDthresholdwasalsoobservedbytheBESIIIcollaborationinthedecayofY(4260),Y(4260)!+??J=[3].