负压波信号的滤波技术研究

2712200312INFORMATIONTECHNOLOGYVOL.27NO.12Dec.2003,,(,150001):;,:;;:TN912.16:A:1009-2552(2003)12-0047-03ResearchonfilteringtechniquefornegativepressurewavesignalsXIEHong,ZHAOGuang,XIEWu(InformationandCommunicationEngineeringCollege,HarbinEngineeringUniversity,Harbin150001,China)Abstract:Thisarticlenarratedtheapplicationofthenegativepressurewavemethodinthe1eakdetectingsys2temoftransporting-oilpipe.Itanalyzedthecharacteristicofnegativepressurewavesignalsandthenoisein2termixedinpressuresignalsinthepracticalpipe,andaneffectivefilteringmethodofnegativepressurewavesignalsisbroughtforward.Keywords:negativepressurewave;filtering;leakdetection0,,,,,,,,,,1,,,;,,:,,,,,:2003-07-29:,,,,74,2,,,,,,,,,,,,1:12.1,,,;,,,,[1],,2.1.1n,x1,x2,,xn,€x=1n(x1+x2++xn)(1)€x,v1,v2,,vn,vi=xi-€x(i=1,2,,n)xm,vm=1n-1vi2(2),(-,+)P=2(z)=12+-exp(-z22)dz(3)z=Pz=3,P=99.73%|vm|3,xm0.27%,,,3,,,,,,2.1.2,n:v1,v2,,vn,n,n,M=nP2i=1vi-ni=nP2+1vi(4)n,M=(n-1)P2i=1vi-ni=(n+3)P2vi(5),,M0,M,2.1.3Abbe-Helmert[2],,,n-1i=1vivi+1n-12(x)(6)2.1.410,,,d(k)2.2,,,84,,,,,1,s(k),n(k),,d(k)=s(k)+n(k),s(k),n(k)y(k),n(k)Pn,Eõe2(k)=Eõ(d(k)-y(k))2=Eõ(s(k)-y(k)+n(k))2(7)y(k)=s(k),,E[e2(k)]min=Pn(8),(LMS),[3],(k)=E{e2(k)}=e{s2(k)}+WTRW-2PTW(9),P=E[s(k)D(k)]s(k)d(k),R=E{D(k)DT(k)}d(k),PR,(k)W,,W0,(9)W0=R-1P,W0=R-1PW0,RP,,Widow-HoffLMS,:e(k)=õs(k)-WT(k)D(k)(10)Widow-Hoff:W(k+1)=W(k)+2e(k)D(k)(11):W(0)=0;k:y(k)=Ni=1wk(i)d(i)(12)N;wk(i),i=1,2,3,,N:(1),:rmax=1P4,,,,,,,[4],,01Pmax(13)maxR,W(n)W0d=maxPmin,,d,,,(2)NNM,M=4P4max(14)M,,10%(M=0.1),(14),max,N,,y(k)(),,,,N1050(3)x(k),d(k);x(k),1,x(k)d(k),,,:,kd(k),d(k+20),,,(53)94(3),IDS,,IDSIETFDARPAIDS[7,8](CIDF,CommonIntrusionDetec2tionFramework)[8],IDS(4)IDS,IDSIDS,,IDSIDS,,,,IDS,IDS,IDSIDS,4(IDS),,DFA,,IDS:[1]http:PP[DBPOL].[2]AndersonP.ComputerSecurityThreatMonitorandSurveillance[M].Technicalreport,JamesPAndersonCo.,FortWashington,Pennsyl2vania,1980.4.[3]DenningDE,Anintrusion-detectionmode[J].IEEETransactiononSoftwareEngineering,1987,13(2):222-232.[4]HarryRLewis,ChristosHPapadimitriou,,..,2000.[5]GuyHelmer,JohneySkwngetal.IntelligentAgentsForIntrusionDe2tection[C],ProceedingsIEEEInformationTechnologyConference,Syracase,NY,1998,121-124.[6],.[J].,2001,(15):5-8.[7]AAtanifordhen,Commonintrusiondetectionframework[EB],ht2tp:PPseclab.cs.ucdavis.eduPcidfP[8]http:PPcs.purdue.eduPcoastPcoast.html:(49)2.323,,,233,,,,,,,,,:[1].[M].:,1988.106-109.[2].[M].:,1995.59-61.[3].[M].:,2003.182-188.[4].[M].:,1995.:35