Distance Education Systems

1. Distance Education Systems Agenda

2. Distance Education Systems Asynchronous Communication: • Delayed ________ between teacher and student. Synchronous Communication • Real-time ________ between teacher and student

3. Asynchronous Technologies “____________ ______" • Print-based • Audio-based • radio • audiotape • Video-based • broadcast television • videotape

4. Print-based Correspondence Normally, learning materials (textbook, study guide) are delivered by _____. Original form of distance education -- dates from mid-_____s.

5. Advantages • Learner-paced • Can be used anywhere • ___ _____ Disadvantages • Limited __________ • Motion cannot be shown • Tarnished _________

6. I opened a letter and read it. it offered me a six months' correspondence course in finger printing at a special professional discount. I dropped it into the wastebasket..." The Big Sleep. by Raymond Chandler

7. "Allied Commissioners' Courses; be a detective, send for a one-volume correspondence course. No tests, no instructors, no salesmen will call. Free handcuffs and badge included as a special bonus if you act now." Good Behavior. by Donald Westlake

8. Audio and Video-based Correspondence Study • Learning materials include __________________________________. • Advantages: similar to print-based.with visual and/or audio component • Disadvantage: limited interactivity

9. Interactive Telecommunications • Audioconferencing • ________ • _________ (ITFS) • Compressed ____ • Fiber-optics

10. Audioconferencing Teacher and students linked by telephone --a “__________ ____." • Advantages: relatively inexpensive, flexible • Disadvantage: lacks visual component

11. Satellite-based Distance Education • “_______" transmits signal to satellite in geosynchronous orbit. T_________ amplifies signal, transmits it back to earth. Signal is received by “_______" (satellite dishes)

12. Satellite

13. Advantages • Huge "f________" means programming can be delivered virtually anywhere to virtually unlimited number of sites Disadvantages • Very expensive to purchase and operate • Normally, video is only ___ ___ and students use telephone to communicate with teacher

14. Microwave-based (ITFS) Distance Education • Essentially, low powered ___ • Special frequencies/channels • Point-to-point or _________ • Line-of-sight, 25-30 miles max. • Usually one-way video, two-way audio

15. Advantages • ____ ______ video • Control over who receives signal • Excellent audio and video quality • No ___________ required Jones. et al., 1992

16. Microwave

17. Disadvantages • Transmissions affected by _______ • _________ only • Limited number of __________ available Jones. et al., 1992

18. Compressed Video-based Distance Education • _____ _____ signal digitized, then: • Processed to reduce unnecessary information transmitted • _______ telephone lines connect sites • Not full-motion--fewer than ___ images per second

19. Advantages • Easy to install and use • Can be c_______ than fiber or microwave Disadvantages: • Motion can be _____ • Video quality can be poor • Can't transmit ___-_____ video Jones. et al., 1992

20. Compressed Video

21. Fiber Optics-based Distance Education • Used for telephone and cable TV main t____ lines • Only recently used for education • Cable uses optically pure _____ • Transmits _____ energy

22. Fiber Optics

23. Advantages • Full-______ _____ • High quality • Unaffected by _______ Disadvantages • ____ start-up costs • Slow, expensive repairs • _____-__-____ costs Jones. et al., 1992