iMac이 정상적으로 종료되지 않고 영원히 로딩 루프 상태로 유지됩니다.

iMac을 종료하려고 할 때마다 로딩 루프에 영원히 갇히게 됩니다. 전원을 끌 수 있는 유일한 방법은 전원 버튼을 길게 누르는 것입니다. 시스템 로그(아래)를 확인했지만 종료가 영원히 반복되는 원인을 찾을 수 없습니다. 어떤 아이디어가 있나요?

Sep 18 06:47:50 Tardis.local GoogleSoftwareUpdateDaemon[3270]: -[KSUpdateCheckAction(PrivateMethods) finishAction] KSUpdateCheckAction found updates: {( )}
Sep 18 06:47:50 Tardis.local GoogleSoftwareUpdateDaemon[3270]: -[KSPrefetchAction performAction] KSPrefetchAction no updates to prefetch.
Sep 18 06:47:50 Tardis.local GoogleSoftwareUpdateDaemon[3270]: -[KSMultiUpdateAction performAction] KSSilentUpdateAction had no updates to apply.
Sep 18 06:47:50 Tardis.local GoogleSoftwareUpdateDaemon[3270]: -[KSMultiUpdateAction performAction] KSPromptAction had no updates to apply.
Sep 18 06:47:50 Tardis.local GoogleSoftwareUpdateDaemon[3270]: -[KSUpdateEngine(PrivateMethods) updateFinish] KSUpdateEngine update processing complete.
Sep 18 06:47:53 Tardis.local com.apple.usbmuxd[1629]: _SendDetachNotification (thread 0x7fff744ab180): sending detach for device d0:23:db:1b:9a:fa@fe80::d223:dbff:fe1b:9afa._apple-mobdev._tcp.local.: _BrowseReplyReceivedCallback got bonjour removal.
Sep 18 06:48:03 Tardis.local com.apple.SecurityServer[20]: Succeeded authorizing right 'system.volume.removable.unmount' by client '/System/Library/CoreServices/Finder.app' [3219] for authorization created by '/System/Library/CoreServices/Finder.app' [3219] (100013,0)
Sep 18 06:48:03 Tardis.local com.apple.SecurityServer[20]: Succeeded authorizing right 'system.volume.removable.unmount' by client '/usr/sbin/diskarbitrationd' [56] for authorization created by '/System/Library/CoreServices/Finder.app' [3219] (100002,0)
Sep 18 06:48:05 Tardis.local webfilterproxyd[3277]: whitelistVerdict: (null) | kitty has no web restrictions | http://init.ess.apple.com/WebObjects/VCInit.woa/wa/getBag?ix=1
Sep 18 06:48:05 Tardis kernel[0]: Sandbox: sandboxd(3279) deny mach-lookup com.apple.coresymbolicationd
Sep 18 06:48:05 Tardis.local webfilterproxyd[3277]: whitelistVerdict: (null) | kitty has no web restrictions | https://tools.google.com
Sep 18 06:48:05 Tardis.local sandboxd[3279] ([3277]): webfilterproxyd(3277) deny job-creation
Sep 18 06:48:07 Tardis.local GoogleSoftwareUpdateDaemon[3270]: -[KeystoneDaemon logServiceState] GoogleSoftwareUpdate daemon (1.1.0.3659) vending:
        com.google.Keystone.Daemon.UpdateEngine: 1 connection(s)
        com.google.Keystone.Daemon.Administration: 0 connection(s)
Sep 18 06:48:09 Tardis.local com.apple.SecurityServer[20]: Succeeded authorizing right 'system.volume.removable.unmount' by client '/System/Library/CoreServices/Finder.app' [3219] for authorization created by '/System/Library/CoreServices/Finder.app' [3219] (100013,0)
Sep 18 06:48:09 Tardis.local com.apple.SecurityServer[20]: Succeeded authorizing right 'system.volume.removable.unmount' by client '/usr/sbin/diskarbitrationd' [56] for authorization created by '/System/Library/CoreServices/Finder.app' [3219] (100002,0)
Sep 18 06:48:15 Tardis.local GoogleSoftwareUpdateDaemon[3270]: -[KeystoneDaemon main] GoogleSoftwareUpdateDaemon inactive, shutdown.
Sep 18 06:48:19 Tardis com.apple.launchd.peruser.502[277] (com.apple.PackageKit.InstallStatus): Throttling respawn: Will start in 9 seconds
Sep 18 06:48:19 Tardis.local WindowServer[106]: CGXGetConnectionProperty: Invalid connection 85271
Sep 18 06:48:19 --- last message repeated 4 times ---
Sep 18 06:48:19 Tardis.local WindowServer[106]: dict count after removing entry for window 0x56c is 0
Sep 18 06:48:19 Tardis com.apple.launchd.peruser.502[277] (com.apple.unmountassistant.useragent[3300]): Exited: Killed: 9
Sep 18 06:48:19 Tardis.local coreservicesd[68]: SendFlattenedData, got error #268435459 (ipc/send) invalid destination port from ::mach_msg(), sending notification kLSNotifyApplicationDeath to notificationID=1538
Sep 18 06:48:19 Tardis com.apple.launchd.peruser.502[277] ([0x0-0x35f35f].com.apple.iTunesHelper[3263]): Exited with code: 1
Sep 18 06:48:19 Tardis.local coreservicesd[68]: SendFlattenedData, got error #268435460 (ipc/send) timed out from ::mach_msg(), sending notification kLSNotifyApplicationDeath to notificationID=1589
Sep 18 06:48:19 Tardis com.apple.launchd.peruser.502[277] (com.apple.mdworker.bundles[3289]): Exited: Killed: 9
Sep 18 06:48:19 Tardis.local WindowServer[106]: CGXGetConnectionProperty: Invalid connection 85271
Sep 18 06:48:20 --- last message repeated 4 times ---
Sep 18 06:48:20 Tardis.local loginwindow[3076]: DEAD_PROCESS: 3076 console
Sep 18 06:48:20 Tardis.local coreservicesd[68]: SendFlattenedData, got error #268435460 (ipc/send) timed out from ::mach_msg(), sending notification kLSNotifyApplicationReady to notificationID=1532
Sep 18 06:48:20 Tardis.local airportd[3194]: _doAutoJoin: Already associated to “Type 40 Tardis”. Bailing on auto-join.
Sep 18 06:48:20 Tardis.local WindowServer[106]: CGXGetConnectionProperty: Invalid connection 85271
Sep 18 06:48:20 --- last message repeated 9 times ---
Sep 18 06:48:20 Tardis.local shutdown[3308]: halt by kitty: 
Sep 18 06:48:20 Tardis.local shutdown[3308]: SHUTDOWN_TIME: 1347976100 852452