简介：Inordertoimprovetheperformanceoflinespectrumdetection,accordingtothefeaturethattheunderwatertargetradiatednoisecontainingstablelinespectrum,thedifferencesofthephasedifferencebetweenlinespectrumandbackgroundnoise,aweightedlinespectrumdetectionalgorithmbasedonthephasevarianceisproposedinfrequencydomain.Afterphasedifferencealignment,thephasevarianceoflinespectrumandthephaseofbackgroundnoise,respectively,aresmallandbiginfrequencydomain,thismethodutilizestheweightedstatisticalalgorithmtocumulatethefrequencyspectrumbasedonthephasevariance,whichcanrestrainthebackgroundnoisedisturbance,andenhancethesignaltonoiseratio(SNR).Thetheoryanalysisandexperimentalresultsbothverifythattheproposedmethodcanwellenhancetheenergyoflinespectrum,restraintheenergyofbackgroundnoise,andhavebetterdetectionperformanceunderlowerSNR.

简介：Thetransmissionspectrumofthecoatedphase-shiftedlong-periodfibergratings(LPFGs)withsingleandmultiplephaseshiftsisanalyzedbythecoupled-modetheoryandthetransfermatrixmethod,andtheinfluencesofthefilmparametersonthespectralcharacteristicsarealsostudied.ItisshownthattheseparameterswillaffecttheLPFGfilteringcharacteristics.Thelosspeakoftransmissionspectrumdecreaseswiththeincreaseoffilmthickness,andthepeakpositionshiftswiththefilmrefractiveindex.Comparedwiththenon-coatedphase-shiftedLPFG,thecoatedonehasthesimilardesirablefilteringcharacteristics,andithasaflexibleabilitytoadjustthetransmissionproperties.

简介：Thedesignreview,simulationandvalidationofaConceptualDesignArchitecture(CDA)forBallisticMissileDefense(BMD)arepresented.AninterceptsystemthatcontainsaGroundBasedInterceptor(GBI)anditsguidancesensors(bothradarandinfrared)aresimulated.3DmodelusingMATLABisdevelopedforamultistagetargetwithascentphaseaccelerationprofilethatdependsontotalmass,propellantmassandthespecificimpulseinthegravityfield.Theradarcrosssection(RCS)andinfraredradiation(IR)ofthetargetstructureisestimatedasafunctionoftheflightprofile.TheKillVehicle(KV)designisexaminedasafunctionoftheKVmass,accelerationcapability,aimpointoffsetandimpactenergytodestroythetarget.TheaimoftheCDAisto:detectthelaunchofathreatballisticmissile,determinewhetherthedetectedobjectisathreat,definethecharacteristicsofthethreatballisticmissile,developafiringsolutiontonegatethethreatballisticmissile,engagethethreatballisticmissile,andassesstheeffectivenessforballisticmissileintercept.ThearchitectureismodeledinMatlab.

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简介：Adefinitionofcombinedphasecenterforhornfeedsisgiven.FormulasofE-planeandH-planecombinedphasecenterforconicalhornsandthecorrespondingOptimalmodelarepresented,andafastoptimizationmethodforsolvingthismodelisdescribed.Byusingthismethod,thephasecenterofcorrugatedhornisdiscussedandcalculated,andthevariationofthephasecenterwithdistanceandoperatingfrequencyisgiven.

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简介：CuprecipitationbehaviorsintwoCu-bearingausteniticantibacterialstainlesssteels,type304andtype317L,weresystematicallystudiedbyusingrelativelysimplemethodsformaterialsanalysis,includingmicro-hardness,electricalresistivity,electrochemicalimpedancespectroscopy,X-raydiffractionanddifferentialscanningcalorimetry.Theresultsindicatedthatafteragingatelevatedtemperature,themicro-hardness,electricalresistivity,electrochemicalimpedanceandlatticeconstantofthesteelwereallvariedatdifferentdegreesduetotheprecipitationandgrowthofCu-richphases.TheresultsalsoshowedthattheheatevolutionduringtheprocessofCuprecipitationcouldbesensitivelydetectedbymeansofdifferentialscanningcalorimetry,obtainningthestartingtemperature,peaktemperature,peakareaoftheCu-richprecipitation,andeventheactivationenergybycalculation.TheresultsconfirmedthattheCu-richphasedprecipitationintheCu-bearingausteniticantibacterialstainlesssteelshouldbeathermalactivationprocesscontrolledbyCudiffusion.AllthematerialsanalysismethodsusedinthisstudycanbemoresimpleandeffectiveforapplicationinR&DoftheCu-bearingantibacterialstainlesssteels.

简介：Inthis,phasecompsitionandthermalexpansionbehaviourofCaOStabilisedrefractorieswerestudied,Specialattentionwaspaidtotheexpasionbehaviourofthreematerialswithdifferentphasecomposition,TheresearchresultsindicatedthattheexpansionbehaviourcouldbeimprovedbymodifyingthestabilizationofZrO2,whichthusleadstotheincreaseinthethermalshockresistanceandpossiblyeroionresistaceofas-obtainedCaOstabilisedZrOmaterial.

简介：Basedonthethermodynamicallyself-consistentanalysisandoptimizationofthreesub-binarysystemsoftheternarysystemPrCl3-CaCl2-MgCl2,thethermodynamicsofthisternarysystemhasbeenstudied.UsingHillertmodelandtakingMgCl2asanasymmetriccomponent,thePrCl3-CaCl2-MgCl2phasediagramhasbeencalculated.Theagreementbetweencalculatedandmeasuredcompositionsandtemperaturesatdeflectingpointsonliquidusisgood.Thesystemisasimpleeutecticonewithaeutecticpointat26.0mol%PrCl3,41.5mol%CaCl2,32.5mol%MgCl2;560℃（calculated）and26.0mol%PrCl3,39.4mol%CaCl2,34.6mol%MgCl2;546℃（measured）,respectively.

简介：InthispaperwepresenttheresultsofstudiesonmakingMgOzirconiasinteredparts(intendedtobeusedasmeteringnozzlesincontinuouscastingofsteel)frommonocliniczirconiaandMgOpowdersviaagranulationprocess.Thepartswerepressedandsinteredunderdifferentconditions,andanalysedforphysicalproperties,microstructureandphasecomposition.WefoundastronginfluenceoftheMgOconcentrationandthesinteringcycle,especiallythecoolingrateonthethermalshockresistance.Thepaperconcludeswithrecommendationsfortheproductionofzirconiameteringnozzlesinaneconomicway.

简介：阶段地水晶(陆军)模型被雇用与格子失配和一个小倾斜角度在飞机凸的底层上模仿取向附生的层的生长的过程。系统的免费精力，取向附生的层的全部的原子序数，和弯曲和底层的角度的效果的变化被分析。结果证明当底层的表面是飞机时，免费精力随底层倾斜角度的增加增加，并且也，取向附生的层的全部的原子序数增加；当底层的表面是凸的时，免费精力随底层角度并且那么也的增加减少取向附生的层减少的全部的原子序数。这是取向附生的层的表面的边疆与增加凸的底层的倾斜角度从步bunching改变到hill-and-valley方面结构的原因。这些结果在对另外的方法结果的好同意。

简介：DuetothedifferentsignalfrequenciesfortheGLONASSsatellites,thecommonly-useddouble-differencingprocedureforcarrierphasedataprocessingcannotbeimplementedinitsstraightforwardform,asinthecaseofGPS.Inthispaperanoveldataprocessingstrategy,involvingathree-stepprocedure,forintegratedGPS/GLONASSpositioningisproposed.Thefirstispseudo-range-basedpositioning,thatusesdouble-differenced(DD)GPSpseudo-rangeandsingle-differenced(SD)GLONASSpseudo-rangemeasurementstoderivetheinitialpositionandreceiverclockbias.ThesecondisformingDDmeasurements(expressedincycles)inordertoestimatetheambiguities,byusingthereceiverclockbiasestimatedintheabovestep.ThethirdistoformDDmeasurements(expressedinmetricunits)withtheunknownSDintegerambiguityfortheGLONASSreferencesatelliteastheonlyparameter(whichisconstantbeforeacycleslipoccursforthissatellite).Areal-timestochasticmodelestimatedbyresidualseriesoverpreviousepochsisproposedforintegratedGPS/GLONASScarrierphaseandpseudo-rangedataprocessing.Otherassociatedissues,suchascycleslipdetection,validationcriteriaandadaptiveprocedure(s)forambiguityresolution,isalsodiscussed.Theperformanceofthisdataprocessingstrategywillbedemonstratedthroughcasestudyexamplesofrapidstaticpositioningandkinematicpositioning.Fromfourexperimentscarriedouttodate,theresultsindicatethatrapidstaticpositioningrequires1minuteofsinglefrequencyGPS/GLONASSdatafor100%positioningsuccessrate.Thesingleepochpositioningsolutionforkinematicpositioningcanachieve94.6%successrateovershortbaselines(＜6km).

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简介：Thedevelopmentofconductingpolymershasbeenanactivesubjectintheworldsincethelatein1970’s.Thepreparationofpolyaeetylene-likepolymersbydehydroehlorinationofpolyvinylchloride(PVC)isaveryeconomicalandusefulprocedureand,hence,afocusofenormousinterestofboththeoretieiansandexperimentalists.Inrecentyears,manymethodsfordehydrochlorinationofPVCinsolutionhavebeenstudiedwidelyandmanykindsofcatalyticmechanismshavebeensuggested.

简介：Thesynthesisandphasebehaviorofaseriesof4’-alkyloxy-4-hydroxybiphenylswerediscribed.Theeffectsofreactionconditionsontheyieldsofproductswereinvestigated.Thecharacterizationsofthermotropicliquidcrystallineproductsforthetypeandthermalpropertiesarediscussedthroughtheuseofdifferentialscanningcalorimetry,polarizingmicroscopy.

简介：AbstractBackground:The significant morbidity and mortality resulted from the infection of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) call for urgent development of effective and safe vaccines. We report the immunogenicity and safety of an inactivated SARS-CoV-2 vaccine, KCONVAC, in healthy adults.Methods:Phase 1 and phase 2 randomized, double-blind, and placebo-controlled trials of KCONVAC were conducted in healthy Chinese adults aged 18 to 59 years. The participants in the phase 1 trial were randomized to receive two doses, one each on Days 0 and 14, of either KCONVAC (5 or 10 μg/dose) or placebo. The participants in the phase 2 trial were randomized to receive either KCONVAC (at 5 or 10 μg/dose) or placebo on Days 0 and 14 (0/14 regimen) or Days 0 and 28 (0/28 regimen). In the phase 1 trial, the primary safety endpoint was the proportion of participants experiencing adverse reactions/events within 28 days following the administration of each dose. In the phase 2 trial, the primary immunogenicity endpoints were neutralization antibody seroconversion and titer and anti-receptor-binding domain immunoglobulin G seroconversion at 28 days after the second dose.Results:In the phase 1 trial, 60 participants were enrolled and received at least one dose of 5-μg vaccine (n = 24), 10-μg vaccine (n = 24), or placebo (n = 12). In the phase 2 trial, 500 participants were enrolled and received at least one dose of 5-μg vaccine (n = 100 for 0/14 or 0/28 regimens), 10-μg vaccine (n = 100 for each regimen), or placebo (n = 50 for each regimen). In the phase 1 trial, 13 (54%), 11 (46%), and seven (7/12) participants reported at least one adverse event (AE) after receiving 5-, 10-μg vaccine, or placebo, respectively. In the phase 2 trial, 16 (16%), 19 (19%), and nine (18%) 0/14-regimen participants reported at least one AE after receiving 5-, 10-μg vaccine, or placebo, respectively. Similar AE incidences were observed in the three 0/28-regimen treatment groups. No AEs with an intensity of grade 3+ were reported, expect for one vaccine-unrelated serious AE (foot fracture) reported in the phase 1 trial. KCONVAC induced significant antibody responses; 0/28 regimen showed a higher immune responses than that did 0/14 regimen after receiving two vaccine doses.Conclusions:Both doses of KCONVAC are well tolerated and able to induce robust immune responses in healthy adults. These results support testing 5-μg vaccine in the 0/28 regimen in an upcoming phase 3 efficacy trial.Trial Registration:http://www.chictr.org.cn/index.aspx (No. ChiCTR2000038804, http://www.chictr.org.cn/showproj.aspx? proj=62350; No. ChiCTR2000039462, http://www.chictr.org.cn/showproj.aspx?proj=63353).

简介：ThispaperisconcernedwiththeH-infinitycontrolproblemforaclassofcascadeswitchednonlinearsystems.Eachswitchedsysteminthisclassiscomposedofazero-inputasymptoticallystablenonlinearpart,whichisalsoaswitchedsystem,andalinearizablepartwhichiscontrollable.ConditionsunderwhichtheH-infinitycontrolproblemissolvableunderarbitraryswitchinglawandundersomedesignedswitchinglawarederivedrespectively.Thenonlinearstatefeedbackandswitchinglawaredesigned.WeexploitthestructuralcharacteristicsoftheswitchednonlinearsystemstoconstructcommonLyapunovfunctionsforarbitraryswitchingandtofindasingleLyapunovfunctionfordesignedswitchinglaw.TheproposedmethodsdonotrelyonthesolutionsofHamilton-Jacobiinequalities.

简介：史蒂夫·里奇（SteveReich）是当今美国现代音乐最具影响力的作曲家之一。文章从材料、调性、节奏、音高组织以及结构等方面，对他作于1967年为两架钢琴所作的《钢琴相位》，进行了综合分析。

简介：这份报纸论述大气的空气的数字分析通过deLaval嘴的接近音速的流动。从本质上讲，大气的空气总是包含水蒸汽的某个数量。计算与高扩大率用一张Laval嘴被做并且一会聚分叉(CD)一半嘴，是指了一接近音速更弥漫，与慢得多的扩大率。计算用内部CFD代码被执行。计算模型使由于在潮湿的空中包含的水蒸汽的自发的冷凝作用模仿液体阶段的形成可能。接近音速的流动计算也在嘴考虑一个正常冲击波的存在分析液体阶段蒸发的效果的超声的部分。