简介：ItisnecessaryforanMC-CDMAuplinkreceivertoemployMUD(multiuserdetection)inafrequencyselectivefadingchannel.AfteranalyzingthealgorithmofPIC(parallelinterferencecancellation)MUD,anovelMUDscheme,Soft-PIC(softparallelinterferencecancellation)isproposed.Basedonthereliabilityofeachdetectedusersignalintheformerstage,thisSoft-PICdetectionschemesubstitutesasoftdecisionofthevariablefortheharddecisioninPICscheme.ComparedwiththePICscheme,itcanreconstructtheinterferencesignalsmoreaccuratelyandeliminateMAI(multipleaccessinterference)inamoreefficientway.PICisoneofthemostpracticalschemesinnumerousmultiuserdetectiontechnologies.However,Soft-PICasanimprovedPICschemedeservesfurtherstudy.

简介：

简介：Theextendingofacantileverandtransversemovingofadrillingfloorenablethejack-uptooperateinseveralwellpositionsaftertheJack-uphaspitched.Thecantileverallowableloadnephogramisthecriticalreferencewhichcanevaluatethejack-up’sdrillingability,designthecantileverstructureandinstructajack-upmanagertomaketheoperationssafe.Theintentofthispaperistoexploretheinterrelationshipsbetweenthecantileverposition,drillingfloorandtheloadsincludingwindforce,thestandset-backweightetc.,throughanalyzingthestructureandloadcharacteristicsofthex-typecantileverandthesimplifiedmechanicsmodelwiththerestrictionofthemaximummomentcapacityofthecantileversinglesidebeam.Referringtoseveraltypicalpositiondesignsloadvalues,thecantileverallowableloadnephogramisobtainedbyusingthesuitableinterpolationmethod.Thepapergivesamethodforcantileverallowableloaddesign,whichisprovedreliableandeffectivebythecalculationexample.