简介:Facede-identificationhasbecomeincreasinglyimportantastheimagesourcesareexplosivelygrowingandeasilyaccessible.Theadvanceofnewfacerecognitiontechniquesalsoarisespeople'sconcernregardingtheprivacyleakage.Themainstreampipelinesoffacede-identificationaremostlybasedonthek-sameframework,whichbearscritiquesofloweffectivenessandpoorvisualquality.Inthispaper,weproposeanewframeworkcalledPrivacy-Protective-GAN(PP-GAN)thatadaptsGAN(generativeadversarialnetwork)withnovelverificatorandregulatormodulesspeciallydesignedforthefacede-identificationproblemtoensuregeneratingde-identifiedoutputwithretainedstructuresimilarityaccordingtoasingleinput.Weevaluatetheproposedapproachintermsofprivacyprotection,utilitypreservation,andstructuresimilarity.Ourapproachnotonlyoutperformsexistingfacede-identificationtechniquesbutalsoprovidesapracticalframeworkofadaptingGANwithpriorsofdomainknowledge.
简介:摘要空间是建筑师永恒的命题。建筑师设计的是空间的形式,现实中需要满足的却是功能的需求,从形式到功能的预测因此成为设计难点,关于空间形式与功能的争论从未停止,然而只有在已有的建筑中,功能和形式才是真正同时可见的。对已有的建筑空间进行准确的分析是对建筑设计初衷最有力的反馈。空间句法是在空间与空间关系的组构理论基础上建立的一种对空间进行客观量化评价的工具,已形成一套完整的理论体系、成熟的方法论、以及专门的空间分析软件技术。作为一种新的描述建筑与城市空间模式的语言,其基本思想是对空间进行尺度划分和空间分割,分析其复杂的内在联系。基于此,本文主要对空间句法理论与建筑空间进行分析探讨。
简介:空间、空间性曾是一个古老的哲学问题,历代很多哲学家都不同程度地探讨过空间问题。20世纪六七十年代以来,随着欧美城市化步伐的突飞猛进,更多的思想家将'空间'作为理论出发点,构建了人类认识生活空间的新模式。本文梳理了空间理论发展的主要脉络,并在此基础上选择空间生产和第三空间理论,来认识和解释大数据时代所建构的网络空间。研究认为,网络空间的现实状态与第三空间的内涵有很多相似之处,网络空间可以被看成是索亚空间旅行的中间驿站,是第三空间发展的定型或阶段性成果。从目前网络空间的发展状况来看,网络空间还呈现出较多的原始社会特征。只有建立起一整套的资源流动和空间规划的法律法规,才能有效构建人类网络命运共同体,才能创造一个和谐有序的网络空间。
简介:Photonics-basedradarwithaphotonicde-chirpreceiverhastheadvantagesofbroadbandoperationandreal-timesignalprocessing,butitsuffersfrominterferencefromimagefrequenciesandotherundesiredfrequency-mixingcomponents,duetosingle-channelreal-valuedphotonicfrequencymixing.Inthispaper,weproposeaphotonicsbasedradarwithaphotonicfrequency-doublingtransmitterandabalancedin-phaseandquadrature(I/Q)de-chirpreceiver.Thisradartransmitsbroadbandlinearlyfrequency-modulatedsignalsgeneratedbyphotonicfrequencydoublingandperformsI/Qde-chirpingoftheradarechoesbasedonabalancedphotonicI/Qfrequencymixer,whichisrealizedbyapplyinga90°opticalhybridfollowedbybalancedphotodetectors.Theproposedradarhasahighrangeresolutionbecauseofthelargeoperationbandwidthandachievesinterference-freedetectionbysuppressingtheimagefrequenciesandotherundesiredfrequency-mixingcomponents.Intheexperiment,aphotonics-basedK-bandradarwithabandwidthof8GHzisdemonstrated.ThebalancedI/Qde-chirpingreceiverachievesanimage-rejectionratioofover30dBandsuccessfullyeliminatestheinterferenceduetothebasebandenvelopeandthefrequencymixingbetweenradarechoesofdifferenttargets.Inaddition,thedesireddechirpedsignalpowerisalsoenhancedwithbalanceddetection.Basedontheestablishedphotonics-basedradar,inversesyntheticapertureradarimagingisalsoimplemented,throughwhichtheadvantagesoftheproposedradarareverified.