1. Distance Education Systems Agenda

2. Distance Education Systems Asynchronous Communication: Delayed ________ between teacher and student. Synchronous Communication Real-time ________ between teacher and student 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 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. 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 _________ 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 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 Audioconferencing ________ _________ (ITFS) Compressed ____ Fiber-optics

10. Audioconferencing Teacher and students linked by telephone --a “__________ ____." Advantages: relatively inexpensive, flexible Disadvantage: lacks visual component 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 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 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 ____ ______ 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 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 _____ _____ 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 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 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 Advantages Full-______ _____ High quality Unaffected by _______ Disadvantages ____ start-up costs Slow, expensive repairs _____-__-____ costs Jones. et al., 1992