简介：摘要目的评价基于CHANNEL流程的气道评估法对急诊困难气道的预测能力。方法从2016年7月至2019年12月，选择北京协和医院急诊科行气道管理的患者，若条件允许，对其同时应用基于CHANNEL流程和改良Mallampati分级(modified Mallampati test, MMT)进行气道评估，完成后予直接喉镜下显露声门继而进行Cormack-Lehane分级。以Cormack-Lehane分级Ⅲ级或Ⅳ级定义为困难气道。采用受试者工作特征（ROC）曲线分别评价应用MMT、CHANNEL流程进行气道评估时预测困难气道的能力。结果接受急诊气道管理的312例患者中有122例被纳入研究，基于CHANNEL流程的气道评估法预测困难气道的灵敏度为100%，特异度为90.1%，曲线下面积（95%可信区间）为0.948（0.907~0.988）。与MMT比较，基于CHANNEL流程的气道评估法对困难气道的预测的ROC曲线下面积更大（P<0.05）。结论基于CHANNEL流程的气道评估法可有效准确预测急诊患者的困难气道。

简介：这份报纸在一条概念的冲积山谷为各种各样的情形论述模仿的隧道模式由一改善二维(2-D)数学模型在同伴纸描述了。从一样的起始的隧道开始，不同隧道模式为改变的边界和起始的条件在250天的一个实时时期上被模仿了包括入口水分泌物和沉积负担，河岸的起始的山谷斜坡，和erodibility。这些控制因素的影响被讨论，以在概念的河山谷的模仿的河的隧道，隧道十字节的几何学，和水表面侧面的纵的底部侧面。因为二部分的沉积运输条件极大地不同，结果建议一样的隧道的上面、更低的部分可以有不同平面形状。在控制变量和隧道模式之间的模仿的原因的关系与已知的隧道模式理论同意品质上。

简介：Theviscouspump,whichhasarotorwithahelicalsquarechannel,isstudiedexperimentally.Thenon-dimen-sionalchannelcurvatureistakentobeabout0.1.Threetypesoftorsionofthechannelaremadetoinvestigatethetorsioneffectontheflowcharacteristics.Wemeasurethefluxthroughthechannelataconstantrotorspeedbychangingthepressuresattheentranceandexitofthepump.Wealsoobservethesecondaryflowatacross-sectionofthechannel.Someoftheresultsobtainedareshownasfollows:Thefrictionfactoralongthechanneltogetthesamefluxislargeforlargechanneltorsionataconstantrotation,andbecomessmallwhenthefavorablerotationoftherotortotheflowisapplied.Asforthesecondaryflowinacross-section,thereappearseveraltypesofvortex.Whenthereisnorotation,thesecondaryflowisalmostasymmetrictwo-vortextypeforsmallfluxasistheordinaryDeanvortex,butitchangestoafour-vortextypewhenthefluxislarge.Thesecondaryflowbecomesasymmetricastherotationisapplied.Wehaveunsteadyflowpatternsatlargefluxandrotation.

简介：Thetime-domainequalizerofADSLChannelplaysanimportantroleinwholereceivingprocesstohighspeedbitstreams.Inthispaper,anovelADSLchannelequalizationmethodbasedonevolutionaryalgorithmisproposed,inwhichweestablishtheequalizerthroughthemethodofchannelidentification.Theproposedmethodiscapableofsimultaneouslyevolvingbothcoefficientsandtheranksoftheequalizerandthereforeitcanbeappliedtodifferentcharacteristicsofloops.Experimentalresultsshowourmethodhasbetterperformance(shortsearchtimeandhighmodelingprecision).

简介：稳定河槽几何学在相当很长时间吸引了水力的工程师的注意。各种各样的标准被建议了解释一条隧道的自我形成的几何学。基于流动系统，和使用的几何编程的最佳的费用结构，现在的调查提出客观功能产出Lacey的稳定河槽尺寸。功能可能是有用的披露稳定河槽几何学的许多详情。

简介：Thispaperconsidersafrequency-divisionduplex(FDD)two-waychannelwithchannelestimationerror,wherechannelgainsareindependentofeachother.Itderivestheexactclosed-formoutageprobabilityexpressionsintheFDDsystemwithanalognetworkcoding(ANC)byuseofprobabilitytheory.Toprovidemoreinsights,anapproximatedversionfortheexactoutageprobabilityisalsodevelopedinthemedium-to-highsignal-to-noiseratio(SNR)region.ThesimulationresultsshowthatthederivedexactoutageprobabilitiesmatchtheresultsofMonteCarlosimulationsinallSNRregions,whiletheapproximatedoutageprobabilitiesalsoapproachthesimulationresultswhenthechannelconditionisgood.ItisinterestingthatANCintheFDDtwo-waychannelisprovedtooutperformthatofinthetime-divisionduplex(TDD)channelbythecomputersimulation.

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简介：Inthequantumkeydistributionsystem,quantumchannelisalwaysaffectedbyspontaneousRamanscatteringnoisewhenittransmitswithclassicalchannelsthatactassynchronizationanddatachannelsonasharedfiber.Tostudytheeffectofthenoiseexactly,thetemporaldistributioncharacteristicsoftheRamanscatteringnoiseareanalyzedtheoreticallyandmeasuredbyasingle-photondetector.Onthebasisofthis,aschemetodecreasethenoiseisproposed.

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简介：Anewall-opticaldemultiplexerbasedonnonlineareffectinsemiconductorlaseramplifier(SLA)isproposed.ItcandemultiplexallchannelsoftheOTDMsignalconcurrently.anditcanalsobeintegratedonasinglechip.TheproposeddeviceconsistsofaseriesshortFabry-Perotamplifiers(FPSLA)settingonthepathverticsally,throughwhichthepreamplifiedopticalsignaltravels.Perpendicularlytothesignal,K(channelnumber)paralleledbeamsoflightpulse,whichactasprobeswithrepetitionatthebitrateofonechannel,irradiateontheseFP-SLAs,respectively,justwhenthecorrespondingsignalchannelpulsepassesthroughtheactiveregionfromlateralside.Thetransmissivitydependsonthesignalpulse.Theoreticalanalysishasbeengiven.Asademonstratingexample,Adeviceoperatedatthespeedof25Gbit/s(2.5Gbit/s×10)issimulatedandtheresultsshowthattheabout9.24dBextinctionratiocanbeachievedeasily.

简介：为有切口的蜿蜒地流的河的一个更新的线性计算机模型被开发了。模型在一条切入的蜿蜒地流的隧道模仿床地形学，流动地，和河岸侵蚀率。在在上游的沉积负担减少的一种情形(例如水坝闭合或土壤保存)，冲积的河经验十字节加深并且斜坡变平。隧道迁居率可能以二个方法被影响：减少的隧道斜坡和浸泡河岸高度。建议数字模型联合传统一个维(1D)在模仿隧道侵蚀的沉积运输模型和为隧道蜿蜒地流的线性模型。一个非平衡沉积运输模型被用来更新隧道床举起和阶段。一个线性蜿蜒地流模型被用来计算隧道排列和河岸侵蚀/生长，它被1D沉积运输模型接着使用。在1D沉积运输模型，隧道床举起和阶段在每隧道十字节被代表。在蜿蜒地流的模型，床举起和阶段被存储在二维(2D)代表隧道和地面性质(举起和阶段)的房间。一个新方法被建议关于在1D河几何学和2D隧道和地面之间的床举起和床材料部分交换信息。模型的能力用隧道切口在发生在在上游的结束的Friedkin的实验室隧道迁居的模拟被表明。

简介：Responseofadaptivematchedfilter,alsocalledadaptivecorrelator,tomultipathchannelisdiscussedinthispaper.Ithasbeenprovedthatthenewtypeprocessorcanbettermatchwithmultipathchan-nel.Theresultsofexperimentcarriedoutonlakeandinlaboratoryarepresented.Itshowsthattheprocessorhasgooddetectingperformanceintimedomain.

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简介：ThevalidityofNavier'spartialslipconditionisinvestigatedbystudyingtheoscillatoryflowinacoatedchannel.Thetwo-fluidmodelisusedtosolvetheunsteadyviscousequationsexactly.Partialslipisexperiencedbythecorefluid.ItisfoundthatNaviersconditiondoesnotholdforanunsteadycorefluid.

简介：Transversemixingcharacteristicsofsoluteintheopenchannelflowcanprovideusefulinformationforriverenvironmentalmanagement.Thelateralmixingcoefficientisacrucialparameterforreproducingthetransversemixingeitherbynumericalsimulationorbyanalyticalprediction.Sincethesolutemixingcanbegreatlyaffectedbythelateralvariationsinwaterdepth,mixingcoefficientshouldbedeterminedineachsub-section(i.e.,themainchannel,sideslopeandfloodplain)separately.Inthisarticle,thetransversemixinginasymmetrictrapezoidalcompoundchannelwasstudiedbasedonlaboratorymeasurementoflongitudinalandtransversevelocitycomponentsandlateraldistributionofsoluteconcentration.ThelateralmixingcoefficientwasestimatedbyadoptingdifferentSchmidtnumbersindifferentsub-sectionsdividedaccordingtothedevelopingtrendoftheeddyviscosity,andfinallyapiecewiselinearprofileofmixingcoefficientwasadoptedtoanalyticallypredictthetransversesoluteconcentration.Thecomparisonbetweentheanalyticallypredicteddataandthemeasuringsoluteconcentrationprovedthatthisisaneffectivewaytoestimatethelateralmixingintheopenchannelflowwithlateralvariationsinwaterdepth.

简介：ThispaperdescribesafullchannelTVmodulatorforallTVsystems,whichhasbeendevelopedsuccessfully.ItemploysadvancedtechniquesuchasPLLfrequencysynthesizerwithmicrowaveintegratedcircuit,andwidebandmicrostripVCOanddigital-analogcombinedintegratedcircuits.Thekeytechniqueofthemodulatorissettledsuccessfully.AllthespecificationsofthemodulatoragreewithTechnicalStandardofChina,whicharetestedbytheauthorityofChina.

简介：Basedontheperiodicstructureofcodeworksoflinearblockcodes,anewideaoflength-varyingcodingdigitalcommunicationssystemisproposedtosavethechannel.Itisshown,byexample,thatupto1/3ofchannelcapacitycanbesavedbythenewsysteminsomespecialsituations.Inordertofindwhichblockcodeissuitabletouseinlength-varyingcodingsystem,theperioddistributionofthecodehastobecal-culated.Newrwsultsabouttheperioddistributionarepresentedwhilemanyopenproblemsremain.

简介：融合是加入流动的集中创造复杂流动和生产强壮的流动发行量并且在床形态学的快速的变化的沉积运输模式的自然、人造的隧道系统的普通特征。由几活动床的隧道融合的实验室实验的工具，这研究(1)调查并且提出(不听说得好)在隧道融合导致沉积的早期的运动的流动和几何条件，并且(2)在主要词法特征上描绘流动和几何条件的效果(例如搜索和免职区域)在融合。在这研究被考虑的主要重要性因素中是流动弗鲁德数字，融合的角度，分泌物和宽度比率和床军事性质。这试验性的研究为更好理解在隧道融合涉及沉积运输和床形态学的机制提供卓见并且也确定沉积上的各种各样的流动和几何因素的影响搬运图案和河的研究，它是在河工程的大重要性。

简介：这份报纸为盲目评价建议了一个方法在水下在由使用的浅水环境的隧道在一个单个水中听音器或从单个beam.First收到了数据，收到的信号借助于信号依赖者TF(时间频率)分发被用于来源信号重建，与即时频率评价和TF倒置联合。然后，浅水的隧道评价被收到的信号和估计的来源信号的使用经由WRELAX技术完成。最后，数字模拟的结果和从在华南海试用拿的真实数据的试验性的测试证明了令人满意。建议方法是有用的为，这被显示出在水下隧道评价。