简介:SegmentationandedgeregulationarestudieddeeplytoextractbuildingsfromDSMdataproducedinthispaper.Buildingsegmentationisthefirststeptoextractbuildings,andanewsegmentationmethod-adaptiveiterativesegmentationconsideringratiomeansquare-isproposedtoextractthecontourofbuildingseffectively.Asub-image(suchas50×50pixels)oftheimageisprocessedinsequence,theaveragegraylevelanditsratiomeansquarearecalculatedfirst,thenthresholdofthesub-imageisselectedbyusingiterativethresholdsegmentation.Thecurrentpixelissegmentedaccordingtothethreshold,theaver-agegraylevelandtheratiomeansquareofthesub-image.Theedgepointsofthebuildingaregroupedaccordingtotheazimuthofneighborpoints,andthentheoptimalazimuthofthepointsthatbelongtothesamegroupcanbecalculatedbyusinglineinterpolation.
简介:目的:探讨3D腔镜辅助甲状腺手术的可行性与安全性。方法2014年1-4月,选择甲状腺单双侧良性病变、甲状腺微小癌以及甲状旁腺病变10例,在3D腔镜辅助下,经颈前胸骨凹上方约一横指处2-4cm弧形切口行局部病灶或患侧腺叶切除,其中2例术中冰冻病理证实甲状腺微小乳头状癌,行患侧Ⅵ区淋巴结清扫。结果10例手术均在3D腔镜辅助下顺利完成,术中无异常出血,无中转开放手术,手术时间30-90min,(61.8±22.4)min;术中出血量1.3-93.0g,中位数5.2g。术后随访1-4个月,未出现喉返神经、喉上神经和甲状旁腺损伤等并发症。结论3D腔镜辅助行甲状腺手术安全、可行,相对于2D技术,空间立体感强,更有利于局部精细解剖,有利于功能保护。
简介:Awhole-field3Dsurfacemeasurementsystemforsemiconductorwaferinspectionisdescribed.Thesystemconsistsofanopticalfiberplate,whichcansplitthelightbeamintoN2subbeamstorealizethewhole-fieldinspection.Aspecialprismisusedtoseparatetheilluminationlightandsignallight.Thissetupischaracterizedbyhighprecision,highspeedandsimplestructure.