SULS UbiLearn The Design Concept of a Simple Ubiquitous Learning System – SULS 一個簡易的無所不在學習系統 SULS 之設計概念 江振瑞 葉明貴 黃宇立 中央大學 資訊工程系

SULS UbiLearn Outline Introduction Preliminary SULS Application scenario Conclusion

SULS UbiLearn Outline Introduction Preliminary SULS Application scenario Conclusion

SULS UbiLearn Introduction(1/4) The improvement of Wireless communications and Micro Electro-Mechanical Systems (MEMS) leads to an age of Ubiquitous Computing

SULS UbiLearn Introduction(2/4) Learning Systems also step from e-Learning, Mobile-Learning to Ubiquitous Learninging With the help of the positioning ability of learning devices and smart objects, the ubiquitous learning system become context aware

SULS UbiLearn Introduction(3/4)

SULS UbiLearn Introduction(4/4) A design concept, SULS – Simple Ubiquitous Learning System, is proposed here to support ubiquitous learning

SULS UbiLearn Outline Introduction Preliminary SULS Application scenario Conclusion

SULS UbiLearn Preliminary(1/7) GPS (Global Positioning System) Line-of-sight between satellite and point node synchronous timer around three satellites APS (Ad-hoc Positioning System) Not need LOS and synchronous timer Based on DVRP( D istance V ector R outing P rotocol) and the trilateration positioning technology DV-Distance, one of the APS methods, is used in SULS

SULS UbiLearn Preliminary(2/7) Anchor node Broadcast it’s Position Anchor node RSSI(received signal strength indicator)

SULS UbiLearn Preliminary(3/7) Anchor node

SULS UbiLearn Preliminary(4/7) RFID (radio frequency identity) Compose of reader, tag and application

SULS UbiLearn Preliminary(5/7) RFID (radio frequency identity) Three kinds of tag Passive tag –no self battery –the simplest one semi-active tag active tag

SULS UbiLearn Preliminary(6/7) RFID (radio frequency identity) How passive tag works?

SULS UbiLearn Preliminary(7/7) RFID(radio frequency identity) Working frequencies in the worldwide 135KHz 13.5MHz MHz 860~930MHz(UHF) 2.45GHz and 5.8GHz The UHF tag can be read at a distance about 10m.

SULS UbiLearn Outline Introduction Preliminary SULS Application scenario Conclusion

SULS UbiLearn SULS(1/7) SULS Simple Ubiquitous Learning System integrates two existent technologies APS RFID three newly developed technologies Farthest tag forwarding Tag-assisted positioning Multi-media data in-network cache

SULS UbiLearn SULS(2/7) Farthest tag forwarding Back-off time = ((L-R)/L) x B Where R:signal source distance L:the farthest signal distance B:the maximum back-off time

SULS UbiLearn SULS(3/7) The farthest signal distance 250 m 200 m 50 m The farthest signal distance= 250 m –Far away from 50m  ((250-50)/250)B=0.8B –Far away from 200m  (( )/250B=0.2B

SULS UbiLearn GUIDE NODE:Node equipped with RFID reader SULS(4/7)

SULS UbiLearn SULS(5/7) Tag-assisted positioning Anchor node can be located by GPS Tags that have position information and are attached to smart objects Other nodes can be located by three GUIDE NODEs

SULS UbiLearn SULS(6/7) Multi-media data in-network cache GUIDE NODE has multi-media data of smart objects Use cache to reduce network traffic and GUIDE NODE loading

SULS UbiLearn GUIDE NODE:Node equipped with RFID reader & multimedia library SULS(7/7)

SULS UbiLearn Outline Introduction Preliminary SULS Application scenario Conclusion

SULS UbiLearn Application scenario

SULS UbiLearn Outline Introduction Preliminary SULS Application scenario Conclusion

SULS UbiLearn Conclusion SULS a Simple Ubiquitous Learning System a low cost and efficient Ubiquitous Learning system use simple devices –Learning devices with mobile ability –Few have RFID readers (plus GPS) three newly developed technologies –Farthest tag forwarding –Tag-assisted positioning –Multi-media data in-network cache

SULS UbiLearn Thanks for Your Listening!