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25 个结果
  • 简介:入侵检测系统(IDS)是一种重要的网络入侵防御手段。IDS面临的主要问题包括误报、漏报、警报粒度过细和IDS自身脆弱性等。为解决前3个问题,在参考有关模型的基础上,提出了基于规则的入侵检测数据融合模型,其结构如图1所示。

  • 标签: 入侵检测系统 网络安全 数据融合模型 结构设计
  • 简介:134Csabranchingpointins-processpathwhichisshowninFig.1.Thebranchingratioisdefinedasfβ=λβ/(λβ+λn).Itcouldbededucedfromtheabundanceof134Baand136Basince136Bagoesthroughbothdecayandneutroncaptureof134Cswhile134Baonlyexperiencesdecaychannel[1].Duetoboth134Baand134Baarepures-processnuclei,thisbranchingpointisagoodapproachtodeterminethes-processparameters.Withtemperaturedependentβ-decayrateof134Cs,thetemperatureofs-processcouldbededuced.

  • 标签: PATH GOES IS BE
  • 简介:InstitutionofModernPhysics(IMP)hasdesigned,fabricatedandinstalledthefirstSRFcavityelectropolishingsystemofChina.It’ssizedfor1.3GHzSRFcavities,andalsocanworksformultiplecellcavitieswithfurtherupgradeofstructure.

  • 标签: Electro-polishing SYSTEM IMP
  • 简介:HierarchicalZSM-11microsphereswithintercrystallinemesoporouspropertiesandrod-likecrystalsintergrowthmorphologyhavebeensynthesizedusingaspotoftetrabutylammoniumasasingletemplate.XRD,FTIR,SEM,TEMandN2adsorptionanalysisrevealedthateachindividualparticlewascomposedofnanosizedrodcrystalsinsertingeachotherandtheintercrystallinevoidsexistingamongrodsgaveasignificantmesoporesizedistribution.Steamtreatmentresultdemonstratedtheexcellenthydrothermalstabilityofsamples.Variouscrystallizationmodesincludingconstanttemperaturecrystallization(one-stagecrystallization)andtwo-stagetemperature-varyingcrystallizationwithdifferent1ststagedurationswereinvestigated.TheresultssuggestedthatthecrystallizationmodesweremainlyresponsiblefortheadjustableparticlesizeandtexturalpropertiesofsampleswhilethesmallamountoftetrabutylammoniumbromidewasmainlyusedtodirecttheformationofbothZSM-11frameworkanditsintergrowthmorphology.Furthermore,theperformanceofoptimalZSM-11asanactivecomponentforthecatalyticpyrolysisofheavyoilwasalsoinvestigated.Comparedwiththecommercialpyrolysiscatalyst,thehierarchicalZSM-11catalystexhibitedahighselectivitytodesiredproducts(LPG+gasoline+diesel),aswellasamuchlowerdrygasandcokeyield,plusahighselectivityandyieldoflightolefins(C=3C=4)andverypoorselectivitytobenzene.Therefore,fullyopenmicropore-mesoporeconnectivitywouldmakesuchhierarchicallyporousZSM-11zeolitesveryattractiveforapplicationsincleanpetrochemicalcatalysisfield.

  • 标签: intercrystalline MESOPORE ROD-LIKE crystal single TEMPLATE
  • 简介:合成了六铝酸盐SrNiAl11O19并用XRD、UVDRS、TGDTA和TEM等技术对其进行了表征。在750℃于SrNiAl11O19上进行的甲烷与二氧化碳重整反应表明,这类催化剂较Ni/SrAl12O19具有较大活性和低积碳能力,在催化反应过程中可有效地抑制Ni颗粒的增大。

  • 标签: 六铝酸盐甲烷重整Ni催化剂
  • 简介:Thehighpowersuperconductingradiofrequency(SRF)inputcoupleristheconnectingpartbetweentheSRFcavityandtheRFtransmissionline.WiththeRFpowertransferredthroughthecoupler,theSRFcavitycanbuiltuptheelectromagneticfieldandthenacceleratethebeams.InadditiontothisRFtransmissionfunction,italsohastoserveasavacuumbarrierfortheSRFcavityvacuum.TheHWR010couplerwhichdesignedbyIHEPisasingleceramicwindowcoupler.

  • 标签:
  • 简介:基于复功率守恒技术编制了分析内壁刻槽TE11-HE11圆波导模式变换器数值计算程序;采用该程序为工作频率为30.5GHz的高功率回旋速调管设计了一半径为16mm的TE11-HE11模式变换器。计算表明该变换器在2.7%的带宽内转换效率在98.8%以上,实验结果表明该变换器性能良好。相对于其他设计技术,该技术具有占用计算机内存极小、分析速度快和精度高的优点。

  • 标签: 高功率 回旋速调管 模式变换 复功率守恒
  • 简介:提出一种借助摄影技术,运用信息技术计算复杂无规则有限电荷面激发场强的方法。该方法借助Matlab的Image函数的读图功能分别读取电荷面图像信息数并将之转换成二维矩阵数字。用电荷面图像的像素点代表电荷面的面元,根据电荷在空间产生的场强理论,通过计算机识别和计算来实现对电荷面所在空间某点场强的求解,算例表明该方法得到的结果与理论计算结果相对误差很小。

  • 标签: MATLAB 像素 电荷面 场强
  • 简介:Takingadvantageofthelargeγ-detectorarrayGammasphereandtherecoilmassseparatorFMA,highspinstatesin117Bawereinvestigatedthroughtherecoil-β-delayedprotondecaytaggingtechniqueviatheheavy-ioninducedfusion-evaporationreaction64Zn(58Ni,2p3n)117Ba,atabeamenergyof305MeV.Promptγraysbelongingto117Bahavebeenidentifiedfurthermore,arotationalbandhasbeenidentifiedforthefirsttimeandpresentedasbandAinFig.1.

  • 标签: ADVANTAGE FMA VIA HAS
  • 简介:Inatwocomponentfermionsystem,themismatchedFermisurfacespreventtheformationofCooperpairsbetweenthetwospicesneartheiraverageFermisurface.Ourpreviouswork[1]hasshownthattheangledependenceofthenons-wavepairinggapcanreducetheeffectofthedifferenceμbetweentheFermisurfacesoftwospicesinasymmetricnuclearmatter.Ontheotherhand,intheheavyfermionsuperconductors,suchasCeCoIn5pressuredCeRhIn5NpPd5Al2andTl-basedcuprates,mayhaveacoupleofcommonfeatures,forexample,thed-wavepairingandastrongparamagneticeffect(thedifferenceofthetwoFermisurfacesμ).Therefore,theangledependenceofthepairinggapmayhavesignificantinfluenceinthesesystems.

  • 标签: COMPONENT FERMION SYSTEM
  • 简介:Theregionaroundthedouble-closedshellnucleus208Pbhasbeenparticularlyusefulinstudyingresidualinteractions.ThelowspinisomersoftheisotopesintheN=127,Z=8387regionhavebeenidentifiedinlastfiftyyearsexcept213Rn[1??4].Inourrecentimplantation–r-acorrelationstudyoftheisotopesaroundtheN=126shellclosure,anewrayisobservedbetweentheimplantationsandthedecaysof213Rn,whichcouldbeduetothedepopulationoftheisomerof213Rnmentionedabove.

  • 标签: Implantation-r-a CORRELATION METHOD
  • 简介:采用与示波器同步的扫描场探测光磁共振,使光磁共振信号稳定;选择扫场的同一点(最好选在峰点或谷点)作参考点。有利于结合实际情况测地磁场水平分量BE11

  • 标签: 光泵 信号 同步 参考点 示波器 扫描
  • 简介:Theoreticalmodelsofstellarevolutionpredictnegligiblequantitiesof6Li,9Be,and11Binthehydrogenburningphasesofastar’sevolution[1].TheprimordialBig-Bangnucleosynthesis(BBN)modelmightbemoregenerousinitsproductionoftheseelements[2].Theradiative-capturecrosssectionforprotoncaptureon11Bleadingto12CissmallatastrophysicallyinterestingenergiesbecauseofthelargeCoulombbarrier.

  • 标签: FACTORS LOW ENERGIES
  • 简介:为解决规则目标物体特征参数的测量问题,提出了一种基于链码的目标物体图像特征参数测量方法。目标物体图像经过灰度变换、平滑去噪等一系列处理后,图像中往往还会存在一些伪边缘信息,针对图像中的这些伪边缘,对图像进行链码跟踪,利用各链码组曲率统计分析的方法剔除目标物体图像中的伪边缘,同时利用像素直线连接的方法将图像中分段的链码组组合连接;然后利用傅里叶变换高频滤波的方法平滑图像边界的曲折部分进一步对图像进行去噪;最后计算目标区域的面积和周长。经实验分析,该方法测量结果精度高,可以实现对规则目标物体特征参数的有效测量。

  • 标签: 图像处理 链码 傅里叶 面积 周长