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.

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简介：量远距传物的进程能被看作量channel.The连续可变远距传物隧道的准确古典能力被介绍，thechannel忠实也被导出。

简介：点火的分叉分析和催化燃烧在的扑灭一突然微隧道被执行，laminar模型作为流动模型合并了。横向的Thiele模量和滞留时间的平方被用作分叉参数。点火和扑灭行为上的不同参数的影响被调查。所有这些参数在点火和扑灭的分叉行为上有大效果在，这被显示出突然微隧道。燃烧的分叉行为上的流动模型的效果也被分析。结果证明与扁平的速度侧面模型比较，为laminar模型的案例，点火的温度和燃烧的扑灭更高，不稳定的多重答案区域更大。

简介：Theoreticalandexperimentalinvestigationsofheattransferinflatcurvilinearchannelhavebeencarriedout.Linearandnon-lineareffectsofDeanvortexesonintensityofheattransferweretakenintoaccount.Thelineareffect,whichdescribeharmonic(sinuous)variationoftheheattransfercoefficientneartheconcavesurfaceofthechannelandthenon-lineareffectcausesthegeneralincreaseoftheheattransfercoefficientduetoaugmentationofheattransferengenderedbytheDeanvortexes.Forbotheffects,mathematicalrelationswereobtainedintheformofquadratures.Thesenumericalresultsweremodifiedtotheformconvenientinengineeringcalculations.TheinvestigationshaveshownthatbothlinearandnonlinearcomponentsgrowupwiththeDeannumber.NonlinearcomponentQ0Tincreasesmoreabruptly,whilethelinearoneQ1Tismoreconservative.Thisisaconfirmationofstabilityofvortexstructures.

简介：Amulti-channelACpowerSupplycontrolerdevelopedrecentlybyuswasintrodueedbrieftyinthispaper.Thiscontrollerisacomputercontrolledmulti-electronic-switchdevice.Thecontrollercontains16independentchannelsinastandardbox(440W×405D×125Hmm).Thereisanelectronicswitchineachchannel,theratedloadpoweris≤1kW.Themainfunctionofthecontrolleristosetthestateofelectronicswitch(ON/OFF)

简介：Low-energypartial-waveπNscatteringdataisreexaminedwiththehelpoftheproductionrepresentationofpartial-waveSmatrix,wherebranchcutsandpolesarethoroughlyunderconsideration.Theleft-handcutcontributiontothephaseshiftisdetermined,withcontrolledsystematicerrorestimates,byusingtheresultsofO(p^3)chiralperturbativeamplitudesobtainedintheextended-onmass-shellscheme.InSnandPuchannels,severediscrepanciesareobservedbetweenthephaseshiftdataandthesumofallknowncontributions.Statisticallysatisfactoryfitstothedatacanonlybeachievedbyaddingextrapolesinthetwochannels.WefindthataSnresonancepolelocatesat√zr=(0.895±0.081)—(0.164±0.023)iGeV,onthecomplexs-plane.Ontheotherhand,aFnvirtualpole,asanaccompanyingpartnerofthenucleonbound-statepole,locatesat√zv=(0.966±0.018)GeV,slightlyabovethenucleonpoleontherealaxisbelowthreshold.Physicaloriginofthetwonewlyestablishedpolesisexploredtothebestofoiirknowledge.ItisemphasizedthattheO(p^3)calculationgreatlyimprovesthefitqualitycomparingwiththepreviousO(p^2)one.

简介：三身体、四身体的界限状态的证据与ultracold原子在一系列很最近的实验被报导了。这里，我们经由一个概括原子分子学习多碱的分子的协调创造黑暗状态的技术。实质上由使中介更整齐或tetramer说unpopulated，二隧道的干扰被显示出起一个重要作用在的建设性的量，例如在ultracold温度的协调atom-pentamer变换。

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简介：A16-channeldualtuningwavelengthdivisionmultiplexer/demultiplexerbasedonsilicononinsulatorplatformisdemonstrated,whichisbothpeakwavelengthtunableandoutputopticalpowertunable.Thewavelengthdivisionmultiplexer/demultiplexerconsistsofanarrayedwaveguidegratingforwavelengthdivisionmultiplexing/demultiplexing,aheaterforpeakwavelengthtuningandavariableopticalattenuatorbasedonp–i–ncarrier-injectionstructureforopticalpowertuning.Theexperimentalresultsshowthattheinsertionlossonchipofthedeviceis3.7dB–5.7dBandthecrosstalkis7.5dB–9dB.Forthetunabilityofthepeakwavelength,1.058-nmwavelengthtunabilityisachievedwith271.2-mWpowerconsumption,andtheaveragemodulationefficiencyis3.9244nm/W;forthetunabilityoftheopticalpower,theopticalpowerequalizationisachievedinall16channels,20-dBattenuationisachievedwith144.07-mWpowerconsumption,andtheraise/falltimeofVOAis35ns/42ns.

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简介：Inrealmultiple-inputmultiple-output(MIMO)systems,theperfectchannelstateinformation(CSI)maybecostlyorimpossibletoacquire.Butthechannelstatisticalinformationcanbeconsideredrelativelystationaryduringlong-termtransmission.Thestatisticalinformationcanbeobtainedatthereceiverandfedbacktothetransmitteranddonotrequirefrequentupdate.Byexploitingchannelmeanandcovarianceinformationatthetransmittersimultaneously,thispaperinvestigatestheoptimaltrans-missionstrategyforspatiallycorrelatedMIMOchannels.Anupperboundofergodiccapacityisderivedandtakenastheper-formancecriterion.Simulationresultsarealsogiventoshowtheperformanceimprovementoftheoptimaltransmissionstrategy.

简介：基于雷纳兹压力方程的简化格式，为各向异性的骚乱模型的一个崭新的旋转修正的方法被介绍了。有模型(=0.1和=1)和标准k-骚乱建模的这新旋转的修改的k-骚乱的三维的海军司烧代码在旋转被用于流动和热转移特征的预言光滑的方形的隧道。雷纳兹数字Re基于冷却空气和水力的直径的入口速度是6000。旋转速度是300，600，900，1200rpm分别地。使用三个骚乱模型的计算结果与试验性的数据相比。研究结果证明(1)旋转修正系数Rf13在新各向异性的k-模型使用了将与标准k-模型相比在后面的表面/铅表面上增加/减少热转移的预言。并且这个趋势将被增加与增加。(2)标准k-模型的模拟表演在领先的表面上好。然而，在走以后出现它下面预言在高旋转的热转移速度。(3)有=0.1的新各向异性的k-模型的计算结果由礼品建议纸与试验性的数据同意了很好，两个在领先、后面的表面上。而且与1相比，0.1是更适当的大小以在现在的论文的条件。

简介：ThispaperdescribesaLeastSquares(LS)channelestimationschemeforMIMOOFDMsystemsbasedontime-domaintrainingsequence.Wefirstcomputetheminimummeansquareerror(MSE)oftheLSchannelestimation,andthenderivetheoptimalcriteriaofthetrainingsequencewithrespecttotheminimumMSE.Itisshownthatoptimaltime-domaintrainingsequenceshouldsatisfytwocriteria.First,theautocorrelationofthesequencetransmittedfromthesameantennaisanimpulsefunctioninaregionlongerthanthechannelmaximumdelay.Second,thecross-correlationbetweensequencestransmittedfromdifferentantennasiszerointhisregion.Simulationresultsshowthattheestimatorusingoptimaltime-domaintrainingsequenceshasbetterperformancethanthatusingoptimalfrequencytrainingsequenceatlowsignal-to-noiseratio(SNR).Toreducethetrainingoverhead,asuboptimaltrainingsequenceisalsoproposed.Comparingwithoptimaltrainingsequence,ithaslowcomputationcomplexityandhightransmissionefficiencyattheexpenseoflittleperformancedegradation.

简介：作为冷却剂的与燃料的再生冷却在超音速冲压式喷气发动机引擎被使用。为了掌握引擎燃料的动态特征，供应过程，这篇文章在隧道以内学习烃燃料的动态特征。一个维的动态模型被证明的A，热精力存储效果，燃料体积效果和化学动态效果在模型，被考虑了平常的微分方程用第4顺序Runge-Kutta方法被解决。模型的精确被三组试验性的数据验证。输入的效果发信号，工作状况，压力的动态特征上的试管尺寸，流动率，温度被模仿了。裂开的反应增加了燃料热分解混合的压缩的可能性，这被发现并且导致插头流动的更长反应的时间。将极大地影响引擎戳系统的控制性能的试管长是5m的插头流动罐头活动范围3s的反应时间。同时，当入口流动率出现时步变化，入口压力导致射，overshoot能到达差不多100%，如此的高度短暂的推动将在燃料泵上导致有害效果。

简介：Inthispaperinvestigationsontheflowpatternsandthethermaldragphenomenoninone-dimensionalinviscidchannelflowwithheatingorcoolingaredescribedanddiscussed:expressionsofflowrateratioandthermaldragcoefficientfordifferentflowpatternsanditsphysicalmechanismarepresented.

简介：Anexperimentalstudyofheattransfercharacteristicsinsuperheatedsteamcooledrectangularchannelswithparallelribswasconducted.Thedistributionoftheheattransfercoefficientontherib-roughedchannelwasmeasuredbyIRcamera.Theblockageratio(e/Dh)ofthetestedchannelis0.078andtheaspectratio(W/H)isfixedat3.0.Influencesoftheribpitch-to-heightratio(P/e)andtheribangleonheattransferforsteamcoolingwereinvestigated.Inthispaper,theReynoldsnumber(Re)forsteamrangesfrom3070to14800,theribpitch-to-heightratioswere8,10and12,andribangleswere90°,75°,60°,and45°.Basedonresultsabove,wehaveconcludedthat:Incaseofchannelswith90°tranverseribs,forlargerribpitchmodels(theribpitch-to-heightratio=10and12),areaswithlowheattransfercoefficientinfrontofribislargeranditsminimumislower,whilethepositionoftheregionwithhighheattransfercoefficientnearlyremainsthesame,butitsmaximunofheattransfercoefficientbecomeshigher.Incaseofchannelswithinclinedribs,heattransfercoefficientsonthesurfacedecreasealongthedirectionofeachribandshowanapparentnonuniformity,consequentlytheregionswithlowNusseltnumbervaluescloselyfollowingeachribexpandalongtheaforementioneddirectionandthatofrelativehighNusseltnumbervaluesvaryinversely.Forasquarechannelwith90°ribsatRe=14800,widerspacingribconfigurations(theribpitch-to-heightratio=10and12)giveanarea-averagedheattransferontherib-roughenedsurfaceabout8.4%and11.4%morethanP/e=8model,respectively;forinclinedparallelribswithdifferentribanglesatRe=14800,thearea-averagedheattransfercoefficientsof75°,60°and45°ribbedsurfacesincreaseby20.1%,42.0%and44.4%incomparisonwith90°ribanglemodel.45°anglerib-roughenedchannelleadstoamaximalaugmentationofthearea-averagedheattransfercoefficientinallresearchobjectsinthispaper.