computer enhanced learning: electronic communication

97/9/16 Clayton College 1

Computer Enhanced Learning:Electronic Communication

Rick Matthews

Dept. of Physics, Wake Forest University

[email protected]

http://www.wfu.edu/~matthews

97/9/16Clayton College and State

University2

Electronic Communications

• Outline– A New Pedagogy?

– Communication

– E-mail

– Listservs

– Usenet

– The Web

– Pedagogy, again


University3

A New Pedagogy?

• Is the computer really going to revolutionize education? In what way?

• Where is the technology going? Where will it be 5 years from now? Ten years from now?

• What are our broad educational goals, and how does computer technology serve these goals?

• What do we want to change, and what should we be careful to preserve?


University4

A New Pedagogy?

Let’s hope the traditional lecture is NOT a good way to teach!

Do we want to be the Tea Room or the Tastee Freeze?

Classroom time is too valuable to waste on one-directional transmission of information.


University5

Short term

• More initial impact on what happens outside the classroom than what happens in the classroom!


University6

Communications

• E-mail

• Listservs

• Usenet

• Web pages


University7

Communications

• E-mail

• Listservs

• Network News

• Web pages

• E-mail:– Familiar, omnipresent.

– Students are more willing to send e-mail than to call.

– If it works well for the students, it can be very time consuming.


University8

Communications

• E-mail

• Listservs

• Network News

• Web pages

• Listservs: an electronic mailing list– You can subscribe members, or invite

users to subscribe themselves.

– No new application for users to learn; messages appear with regular mail.

– Excellent forum for discussions outside of class. Example: English literature.

– More efficient, and perhaps better, than e-mail for answering student questions.

– Disadvantages: All discussions are mixed with your regular e-mail. (Solution: Filters.) Discussions are not threaded.


University9

Communications

• E-mail

• Listservs

• Network News

• Web pages

• Network News, or Usenet, is a set of thousands of online discussion groups– You can create local groups accessible to

just your faculty and students.

– Discussions are separate from e-mail.

– Discussions are threaded by topic.

– Limited privacy

– Articles are read with a different application (maybe). Messages do not appear in your mailbox.


University10

Communications

• E-mail

• Listservs

• Network News

• Web pages

• Web Pages– Web use is ubiquitous -- students already

know how to use it.

– Publication is cheap and easy. Gutenberg II.

– Rich presentations, multiple fonts, images, equations, sound, video.

– Hypertext offers a different paradigm for presentation.

– Students can be “published” internationally.

– Communication is one-way (usually!).


University11

Communications

• E-mail

• Listservs

• Network News

• Web pages

• WFU Physics uses of Web pages– See http://www.wfu.edu/physics.

– Class syllabus, indexed on student government pages.

– Homework assignments, solutions.

– Links to relevant sites.

– Last minute information, weather reports, satellite images for Astronomy labs.

– Official information for graduate and undergraduates. Online applications.

– Classroom demonstrations.


University12

Communications

• E-mail

• Listservs

• Network News

• Web pages

• More uses– Online threaded discussion, much like Usenet.– Student pages

• Not just ego-booster (though that helps).• Students can publish papers, other students

can critique.– Student Web searches

• Much is trash.• Much printer matter is trash, too!• Students need to learn how to judge the

value of what they see.


University13

Communications

• E-mail

• Listservs

• Network News

• Web pages

• Content!

• Ease of use!– Find out the fastest, most efficient way of

getting your information on the Web.

• Frontpage

• Word97 (get the latest plugin: w97au.exe) or Word95 with IA

• Netscape Composer

• Scanned text


University14

Style

• HTML– Standard markup, “styles”: essential for good pages

• Normal

• H1, H2, etc.

• PRE, handy for existing documents with tables

– HTML is not WYSIWYG.• Viewer may not even have graphical browser.

• If the same brand of browser, settings may be different. Mark content, not layout.


University15

Web Authoring

• HTML Style Elements– Numbered list, <OL>

– Bulleted list, <UL>

– Horizontal rule, <HR>

– Note: bold and italics are supported, but HTML purists do not use them. Instead consider “Strong” or “Emphasis”.


University16

Graphics

• Goal: high quality, small size.

• Size is important, very important.

• Rule of thumb: Time = 1 second per Kbyte + 3 seconds per file– Lots of 1 K buttons add tremendously to download

time; it’s not just file size.

– This will get better with http1.1.

• Don’t forget the value of caching! Reuse images.

• Pick the right format: GIF or JPG.


University17

Graphics: file type

• GIF, JPG, TIF, BMP, WMF, PNG, PCX: why all these file types?

• How do we represent color?– One number each for R, G, B.

– TrueColor: 256 levels each for R, G, B • 3 x 8 bits = 24 bits per pixel = 3 bytes per pixel

• 800 x 600 image x 3 bytes/pixel = 1.44 Megabytes!

• TIF, BMP – Full TrueColor representation, no compression


University18

Graphics: compression• GIF

– Invented to reduce file size.

– Reduces number of colors in image to a maximum of 256 (and a minimum of two), using a palette of 24 bit colors.

– Repeated colors are replaced by a single entry and a repeat number: [17][17][17][17] becomes 4x[17].

– Works great on line drawings, computer art. • Full representation of image without loss.

• Small file sizes.

– Not so great on photographic images.


University19

Graphics: compression

• JPG– Invented to compress photographic images

– Works best where GIF works poorly: continuous tone images.

– Compresses by discarding spatial frequencies the eye does not notice.

– Quality (and file size) is adjustable.

– Supports TrueColor.

– Terrible for line drawings, computer art.


University20

JPG vs. GIF

Original:2000x1600 truecolor


University21

JPG vs. GIF

1 Meg 2.4 Meg


University22

JPG vs. GIF

1 Meg 2.4 Meg


University23

JPG with extreme compression vs. GIF

134 K 2.4 Meg


University24

5k GIF

16k JPG

JPG vs. GIF: Computer generated image


University25

Graphics: choosing file types

• Computer art and line drawings:– Always use GIF

• Photographic images– Save the original as BMP, TIF, or PNG

– Put JPG on the Web

• The future:– PNG will replace GIF ( I hope!), but will not replace

JPG.


University26

Web pages: special concerns for math and science

• HTML does not support mathematical expressions and equations.

• Methods:

– Scanned handwritten text

• Easy, viewable by most, not very pretty.

– IBM TechExplorer (http://www.ics.raleigh.ibm.com/ics/techexp.htm)

• As easy as Tex.

• Requires a plug-in only available on the most popular platform, but accessible to anyone with Tex.

– Include equations as images

• Viewable by most browsers

• Easy with Microsoft Word97


University27

Including equations with Word

• Initial setup of the equation editor on the toolbar:– Click on “Tools” and then “Customize”.– Select the “Commands” tab.– Select “Insert” from the left window.– Drag equation editor icon (“”) from the right window to

the toolbar. Click on equation editor icon, create equation using equation toolbar.

• Equations will be included as a GIF files.• Warning: equations cannot be edited later unless also

saved as *.doc.


University28

HTML <HEAD> information

• Header information– Important!

• Titles are what appear in bookmark list.

• Subject, keywords, description are used by search engines to index your page.


University29

Meta tags in HTML source

• <HTML><HEAD><TITLE>Your title goes here</TITLE><META NAME="subject" CONTENT=”Your subject here"><META NAME="keywords" CONTENT= "Keyword1 keyword2" ></HEAD><BODY TEXT="#000000" BGCOLOR="#ffffff"><P>This is the body.</P></BODY></HTML>

• Modern Web authoring tools offer an easier way!


University30

Adding title and meta tags in Word97

•Click on File, Properties to bring up the window shown at right.•Click on “More”.


University31


On the Summary tab, you will find slots for title, subject, description, etc.


University32


• Select Custom tab.

• Enter the word “Description” in the “Name” slot.

• Enter a description of your document in the “Value” slot.


University33

Adding Meta Tags in Netscape

• Netscape Communicator offers a similar entry window.

• Select “Format”, “Page Colors and Properties” to call up this window.


University34

Editing HTML directly

• HTML looks much like the old pre-WYSIWIG word processors.

• Can use the “Edit source” option of Word, or edit directly with Notepad, emacs, vi, etc.


University35

Final thoughts on Web design

• Content, Content, Content.

• Keep graphics file size down, unless graphics are the focus. Consider thumbnails linked to bigger pictures.– Use GIFS for computer generated pictures and line art.– Use JPGs for photographs. Adjustable compression.– Reuse graphics where possible, and refer consistently.– Use “Height” and “Width” tags.

• My rule of thumb: Time in seconds = (3x #files) + (Total size in K)Keep time under 45 seconds.

• Site should be navigable without graphics.

Time


University36

Pedagogy again

• Bob Swofford: “We are in the ‘bolt-on’ technology phase.”

• Where do you see us going?

• What are the pitfalls?

computer enhanced learning: electronic communication

Documents

new application

classroom time

regular email

student pagesnot

student questions

classroom demonstrations

computer technology

student web searchesmuch