简介：Reactionofglycinewithphosphorustrichlorideinpresenceoftriethylaminehasurnishedtheovelspirohydridophosphorane.Itsstructurehasbeencharacterizedbyelementalanalysis,n.m.r.spectraandmassspectrum.Thecompoundreactedwithphenylisothiocyanatetogive2-phenyliminothiazolid-5-one.

简介：Thisresearchaimstocomparedifferentstrategiesthatanon-professionalinvestorinexchange-tradedfunds(ETFs)couldemploytoreachagoodperformancebothfromprofitsandfromariskperspective.Inrecentyears,especiallyafterthe2008crisis,anewtechniquetoevaluatetheriskhasbecomemorepopular,theso-calledriskparity,whichseekstoequalisethecontributionstoriskoftheportfolioconstituents.Ourstudyanalyses17variantsofriskparityportfoliodesignforgroupswiththeminimumvariancestrategyandequallyweightedportfoliooverapoolof56ETFs—listedontheItalianStockExchange—ofeightdifferentcategoriesofspecialisation.Empiricalresultsconfirmtheusefulnessofthegroupriskparitystrategiesinimprovingoutcomesregardingdiversificationofrisksamongclasseswithgoodout-of-sampleperformancewithrespectstothetargetmodels.

简介：TheauthorsgivesomeconstructivefactorizationtheoremsforpluriharmonicmapsfromaKaehlermanifoldintotheunitarygroupU(N)andobtainsomeoptimalupperboundsofminimalunitonnumbers.

简介：LetM(2)bethegroupofrigidmotionsoftheplane.TheFouriertransformandthePiancherelformulaonM(2)canbeexplicitlygivenbythegeneralgrouprepresentationtheory.Usingthisfact.weestablishakindofuncertaintyprincipleonM(2).Theresultcaneasilybegeneralizedtohigherdimensionalcases.AnapplicationoftheresultyieldsanuncertaintyprincipleontheEuclideanspacesobtainedbyR.S.Strichartz.

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简介：TheDalianFujiaGroupbyhinginguponthearomaticsprojectandmakinguseofitsownadvantagesintendstolaunchtheconstructionofthenaphthasteamcrackingandtheMTOprojectinordertodevelopthemanufactureofethylene,propyleneandtheirdownstreamhigh-gradeorganicsynthesismaterials,specialtychemicalfeedstocksandfunctionalhighmolecularmaterials.Theproposedsizeofproductionunits

简介：让f在局部性的非各向同性的Sobolev空间W_(loc)~(1，p)(H~n)在n维的海森堡组H~n=C~nxR，在此1≤p<2是的Q和Q=2n+H~n的同类的尺寸。假定椭圆形的坡度是的潜水艇gloabllyL~pintegrable，即，f_(H~n)|▽_(H~n)f|~pdu是有限的。我们在全部spaceH~n上为f证明Poincare是不平等。用我们证明的这不平等，减去某个常数的功能f在thenonisotropicSobolev空间，这在标准下面由C_0~∞(H~n)的结束形成了(∫_(H~n)|f|~((Q_p)/(Q-p)))~((Q-P)/(Q_p))(∫_(H~n)|▽_(H~n)f|~p)~(1/p)。我们将也证明为H~n上的如此的Poincare不平等的最好的常数和extremals与为H~n上的Sobolevinequalities的那些一样。用到L~(2Q)/(Q-2)的锋利的常数和extremalsforL~2上的Jerison和李的结果海森堡组上的Sobolev不平等，我们因此在H~n上为上述的Poincare不平等到达明确的最好的常数什么时候p=2。我们也在HeisenberggroupH~n上在公制的球上为本地Poincare不平等导出最好的常数的更低的界限。

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简介：一个抑制模型为与数据包退学学生一起的联网的控制系统的预兆的控制(MPC)算法在这篇论文被建议。一个缓冲区被设计存储在控制器和致动器之间的预言的控制顺序。MPC的控制地平线是否是，被看那不少于数据包的数字连续地输了，在起始的时间的MPC的可行性暗示靠近环的系统的asymptotical稳定性。一个模拟例子说明建议途径的有效性。

简介：重点知识园地重点单词1.bothadj.&pron.两个;两个都Boththeanswersareright.两个答案都对。BothofthemareinterestedinEnglish.他们两个都对英语感兴趣。可构成both...and...结构,意为'不仅……而且……'。可连接两个并列的成分,若连接两个并列的主语。

简介：AIM:Toidentifywhethertheforcepsestimationismoreusefulthanvisualestimationinthemeasurementofcolonpolypsize.METHODS:Werecordedcolonoscopyvideoclipsthatincludedscenesvisualizingthepolypandscenesusingopenbiopsyforcepsinassociationwiththepolyp,whichwereusedforanexam.Atotalof40endoscopistsfromtheBusanUlsanGyeongnamIntestinalStudyGroupSociety(BIGS)participatedinthisstudy.Participantswatched40pairsofvideoclipsofthescenesforvisualestimationandforcepsestimation,andwrotedowntheestimatedpolypsizeontheexampaper.Whenanalyzingtheresultsoftheexam,weassessedinterobserverdifferences,diagnosticaccuracy,anderrorrangeinthemeasurementofthepolypsize.RESULTS:Theoverallintra-classcorrelationcoefficients(ICC)ofinter-observeragreementforforcepsestimationandvisualestimationwere0.804(95%CI:0.731-0.873,P<0.001)and0.743(95%CI:0.656-0.828,P<0.001),respectively.TheICCsofeachgroupforforcepsestimationwerehigherthanthoseforvisualestimation(Beginnergroup,0.761vs0.693;Expertgroup,0.887vs0.840,respectively).Theoveralldiagnosticaccuracyforvisualestimationwas0.639andforforcepsestimationwas0.754(P<0.001).Inthebeginnergroupandtheexpertgroup,thediagnosticaccuracyfortheforcepsestimationwassignificantlyhigherthanthatofthevisualestimation(Beginnergroup,0.734vs0.613,P<0.001;Expertgroup,0.784vs0.680,P<0.001,respectively).Theoverallerrorrangeforvisualestimationandforcepsestimationwere1.48±1.18and1.20±1.10,respectively(P<0.001).Theerrorrangesofeachgroupforforcepsestimationweresignificantlysmallerthanthoseforvisualestimation(Beginnergroup,1.38±1.08vs1.68±1.30,P<0.001;Expertgroup,1.12±1.11vs1.42±1.11,P<0.001,respectively).CONCLUSION:Applicationoftheopenbiopsyforcepsmethodwhenmeasuringcolonpolypsizecouldhelpreduceinter-observerdifferencesanderrorrates.

简介：AccordingtothestatisticaldatafromtheStatisti-calDepartmentofTibet,theTibetAutonomousRe-gionboastedapopulationof2736800peopleattheendof2004,anincreaseof35100overthepreviousyear.Thebirthrateandthenaturalpopulationgrowthwere17.4%and11.2%respectively.Inthepasthalfacen-

简介：Sleevegastrectomy(SG)isarestrictivebariatricsurgerytechniquethatwasfirstusedaspartofrestrictivehorizontalgastrectomyintheoriginalScopinarotypebiliopancreaticdiversion.Itsgoodresultsasasingletechniquehaveledtoariseinitsuse,anditiscurrentlythesecondmostperformedtechniqueworldwide.SGachievesclearlybetterresultsthanotherrestrictivetechniquesandiscomparableinsomeaspectstotheRoux-en-Ygastricbypass,thecurrentgoldstandardinbariatricsurgery.Thesebenefitshavebeenassociatedwithdifferentpathophysiologicmechanismsunrelatedtoweightlosssuchasincreasedgastricemptyingandintestinaltransit,andactivationofhormonalmechanismssuchasincreasedGLP-1hormoneanddecreasedghrelin.TheaimofthisreviewwastohighlightthesalientaspectsofSGregardingitshistoricalevolution,pathophysiologicmechanisms,mainresults,clinicalapplicationsandperioperativecomplications.

简介：重点词汇1.bothadj.&pron.两个;两个都Boththeanswersareright.两个答案都对。BothofthemareinterestedinEnglish.他们两个都对英语感兴趣。可构成both…and…结构,意为'不仅……而且……'。可连接两个并列的成分,若连接两个并列的主语,谓语动词用复数形式。BothyouandIwerewrong.你和我都错了。注意:both…and…的否定式为neither…nor…意为'既不……,也不……'。

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简介：Apathfollowingcontrollerisdevelopedforunderactuatedshipswithonlysurgeforceandyawmomentavailabletofollowapredefinedpath.Theproposedcontrollerisbasedonnonswitchanalyticmodelpredictivecontrol.Itisshownthattheoptimalcontrollawforanonlinearpathfollowingsystemwithill-definedrelativedegreeiscontinuousandnonsingular.Theproblemofill-definedrelativedegreeissolved.Thepath-followingabilityofthenonlinearsystemisguaranteed.Numericalsimulationsareprovidedtodemonstratetheeffectivenessoftheproposedcontrollaw.

简介：Akindofnetworkedcontrolsystemisstudied;thenetworkedcontrolsystemwithnoisedisturbanceismodeledbasedoninformationschedulingandcontrolco-design.Augmentedstatematrixanalysismethodisintroduced,androbustfault-tolerantcontrolproblemofnetworkedcontrolsystemswithnoisedisturbanceunderactuatorfailuresisstudied.Theparametricexpressionofthecontrollerunderactuatorfailuresisgiven.Furthermore,theresultisanalyzedbysimulationtests,whichnotonlysatisfiesthenetworkedcontrolsystemsstability,butalsodecreasesthedatainformationnumberinnetworkchannelandmakesfulluseofthenetworkresources.

简介：Nonlinearcontrollabilityandattitudestabilizationarestudiedfortheunderactuatednonholonomicdynamicsofarigidspacecraftwithonevariable-speedcontrolmomentgyro(VSCMG),whichsuppliesonlytwointernaltorques.Nonlinearcontrollabilitytheoryisusedtoshowthatthedynamicsarelocallycontrollablefromtheequilibriumpointandthuscanbeasymptoticallystabilizedtotheequilibriumpointviatime-invariantpiecewisecontinuousfeedbacklawsortime-periodiccontinuousfeedbacklaws.Specifically,whenthetotalangularmomentumofthespacecraft-VSCMGsystemiszero,anyorientationcanbeacontrollableequilibriumattitude.Inthiscase,theattitudestabilizationproblemisaddressedbydesigningakinematicstabilizinglaw,whichisimplementedthroughanonlinearproportionalandderivativecontroller,usingthegeneralizeddynamicinverse(GDI)method.Thesteady-stateinstabilityinherentintheGDIcontrolleriselegantlyavoidedbyappropriatelychoosingcontrolgains.Inordertoobtainthecommandgimbalrateandwheelaccelerationfromcontroltorques,asimplesteeringlogicisconstructedtoaccommodatetherequirementsofattitudestabilizationandsingularityavoidanceoftheVSCMG.Illustrativenumericalexamplesverifytheefcacyoftheproposedcontrolstrategy.

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