简介:Dempster-Shaferevidencetheory(DStheory)iswidelyusedinbrainmagneticresonanceimaging(MRI)segmentation,duetoitsefficientcombinationoftheevidencefromdifferentsources.Inthispaper,animprovedMRIsegmentationmethod,whichisbasedonfuzzyc-means(FCM)andDStheory,isproposed.Firstly,theaveragefusionmethodisusedtoreducetheuncertaintyandtheconflictinformationinthepictures.Then,theneighborhoodinformationandthedifferentinfluencesofspatiallocationofneighborhoodpixelsaretakenintoconsiderationtohandlethespatialinformation.Finally,thesegmentationandthesensordatafusionareachievedbyusingtheDStheory.ThesimulatedimagesandtheMRIimagesillustratethatourproposedmethodismoreeffectiveinimagesegmentation.
简介:Thephotocurrent-voltagecharacteristicsandphotoelectricsensitivityofa-Si:Hsampleswithslitandcombelectrodesaremeasured.Amethodforcalculatingthechargeintensifyinggainfromthephotoelectricsensitivityisproposed.Theobtainedchargeintensifyinggainofa-Si:Hunderanelectricfieldof105V/cmthroughthismethodisashighas4.3×103.Thegenerationprocessofthechargeintensificationeffectina-Si:Hisdiscussedonthebasisoftheenergyleveldiagram.Andtheproductofelectron’smobilityanditslifetimeiscalculatedfromthemeasuredvaluesofthegains.