2. The Internet
• What does a network do: It lets us communicate.
• Start by thinking of a telegraph machine.
a talker hits a key and a pulse is sent along a wire to a receiving station
at the receiving station a listener hears the pulses
the sequence of the pulses (morse code) determine the message
the two take turns talking and listening to communicate
• Computer networks work exactly the same way (just a bit faster)
instead of keying stations we have network cards and cables
there are many talkers and listeners
instead of Morse code we use ASCII to transmit letters, numbers, etc.
there are certain methods for determining who is listening and who is talking (eg, FTP)
• A small network is called a Local Area Network (LAN) and only connects a few computers for fast communication.
• We can connect smaller networks to larger networks that may just go across campus. These are Wide Area Networks (WAN).
• The Internet is just a lot of LANs and WANs connected together. If your computer is on one LAN that is connected to the Internet, you can reach computers on other LANs.
• The information that networks typically communicate includes,
email: text files, binary files (MIME encoded)
programs: binary, or uuencoded
web pages: (HTML) Hyper Text Markup Language
• To transfer this information we count on access procedures that allow agreement about when computers talk and listen, and what they say.
email: (SMTP) Simple Mail Transfer Protocol, POP3, IMAP
programs: (FTP) File Transfer Protocol
login sessions: Telnet
web access: (HTTP) Hyper Text Transfer Protocol
2.1 Computer Addresses
• Computers are often given names, because names are easy to remember.
• In truth the computers are given numbers.
• When we ask for a computer by name, your computer must find the number. It does this using a DNS (Domain Name Server). On campus we have two ‘18.104.22.168’ and ‘22.214.171.124’.
• The number has four parts. The first two digits ‘148.61’ indicate to all of the internet that the computer is at ‘gvsu.edu’, or on campus here (we actually pay a yearly fee of about $50 to register this internationally). The third number indicates what LAN the computer is located on (Basically each hub has its own number). Finally the last digit is specific to a machine.
2.2 Network Types
• The network connection type has an impact on the effectiveness and cost of the connection.
2.2.1 Permanent Wires
• These networks are fast, but require a permanent connection
• For the campus network the peak data transfer rate is about (4 GB/hour)
• These types of networks include,
2.2.2 Phone Lines
• The merit dialup network is a good example. It is an extension of the internet that you can reach by phone.
• The phone based connection is slower (about 5 MB/hour peak)
• There are a few main types,
SLIP: most common
PPP: also common
ISDN: an faster, more expensive connection, geared to permanent connections
• You need a modem in your computer, and you must dial up to another computer that has a modem and is connected to the Internet. The slower of the two modems determines the speed of the connection. Typical modem speeds are,
52.4 kbps: very fast
28.8/33.3 kbps: moderate speed, inexpensive
14.4 kbps: a bit slow for internet access
2.4, 9.6 kpbs: ouch
300 bps: just shoot me
2.3 Network Protocols
• What are protocols: sequences that computers must follow when sending and receiving information. These agreed methods make sure that information is sent and received correctly.
• Why do we need protocols: Without some agreement about what information is arriving over the network, it would just seem like garbage. This would be like somebody suddenly sending stock market numbers by morse code without telling us what it is.
2.3.1 Mail Transfer Protocols
• Popular email methods include,
SMTP (Simple Mail Transfer Protocol): for sending mail
POP3: for retrieving mail
IMAP: for retrieving mail
• Note that the campus mail system ‘ccmail’ is not standard. It will communicate with other mail programs using standard services, but internally special software must be used. Soon ccmail will be available using the POP3 standard, so that you will be able to view your ccmail using Netscape, but some of the features of ccmail will not be available.
• Listservers allow you to send mail to a single address, and it will distribute it to many users (IT can set this up for you).
126.96.36.199 - Attachments
• We can attach files to our email. It is normally stored using the MIME format.
• These formats will allow the files to travel with the text of the message, and then be extracted by the receiver.
188.8.131.52 - Mail Lists
• We can set up mail servers that will accept a mail message addressed to the group, and then distribute it to the individual users.
2.3.2 FTP: File Transfer Protocol
• This is a method for retrieving or sending files to remote computers.
• These are informal groups (from local to international). The groups allow ongoing discussions between many individuals.
• You can get newsgroups set up for your courses to allow student discussions (just ask the IT people). This is a good alternative to chat groups.
• Notice that newsgroups have messages spanning a period of time. If the time period for message storage is the length of the term, the group will act as a permanent record of discussions.
2.3.4 HTTP: Hypertext Transfer Protocol
• This is the protocol used for talking to a web server.
• chat groups allow on-line conversations. If we compare these to newsgroup: these are realtime by nature.
• Allows us to share files stored on a server.
• Security problems usually arise through protocols. For example it is common for a hacker to gain access through the mail system.
• The system administrator is responsible for security, and if you are using the campus server, security problems will normally be limited to a single user.
• Be careful with passwords, this is your own protection again hacking. General rules include,
1. Don’t leave yourself logged in when somebody else has access to your computer.
2. Don’t give your password to anybody (even the system administrator).
3. Pick a password that is not,
in the dictionary
some variation of your name
all lower case letters
found in television
star trek, the bible
4. Watch for unusual activity in you computer account.
5. Don’t be afraid to call information technology and ask questions.
6. Don’t run software that comes from suspect or unknown sources.
7. Don’t write your password down or give it to others.
2.4 Data Formats
• The format of the data is important so that other programs may interpret it correctly.
2.4.1 HTML: Hyper Text Markup Language
• This is a format that is invisible to the user on the web. It allows documents to be formatted to fit the local screen.
• Editors are available that allow users to update HTML documents the same way they use word processors.
184.108.40.206 - Publishing Web Pages
• Once a web page has been modified it is necessary to put it back on the web server.
• When publishing a page with a browser ‘FTP’ will be used.
• The web page called ‘index.html’ is the first one to be returned. If you are publishing a main page your main page should be called ‘index.html’.
• Keep in mind that the website is just another computer. You have directories and files there too. To create a web site that has multiple files we need to create other files or directory names.
• Note that some web servers do not observe upper/lower case and cut the ‘html’ extension to ‘htm’. Microsoft based computers are notorious for this, and this will be the most common source of trouble.
• In HTML documents we need to refer to resources. To do this we use a label to identify the type of resource, followed by a location.
• Universal Resource Locators (URLs)
• Below is a list of hints for publishing web pages
Windows will not allow multiple applications to open the same file at the same time. If you seem to be having trouble opening a file, make sure it is not open in another application.
As you add other files to your homepage, put them in the ‘temp’ directory. This will make all of the procedures simpler.
Try to make your web pages small, and link them together. This will decrease download time and make browsers happier.
Avoid using excessive images. Anything over 10K will make it very slow downloading over modem. Anything over 100K makes modem downloading painfully slow.
When putting images on the web page use ‘jpg’ for photographic images, and ‘gif’ for line images. ‘jpg’ images can be compressed more than ‘gif’, but lines will become blurred.
To link to other files or web pages there will be a ‘link’ command. If you want to add a file that is in your ‘temp’ directory, just put the name of the file in the ‘URL’ field.
Watch upper/lower case. This is a major cause of web page problems.
2.4.4 Specialized Editors
• There are a variety of editors that will allow us to edit single web pages or entire sites.
• These programs include,
• A format proposed by Adobe. This is not a ‘standard’, but is very widely accepted.
• When documents are presented in pdf format their original layout is preserved (HTML will actually change the look/layout of a document), but the files become hard/impossible to work with.
• A special plug-in is required to view these files.
• Allows some degree of privacy, but this is not guaranteed.
• Basically, if you have something you don’t want seen, don’t do it on the computer.
• We can make a file smaller by compressing it (unless it is already compressed, then it gets larger)
• File compression can make files harder to use in Web documents, but the smaller size makes them faster to download. A good rule of thumb is that when the file is MB is size, compression will have a large impact.
• Many file formats have compression built in, including,
images: JPG, GIF
video: MPEG, AVI
programs: installation programs are normally compressed
• Typical compression formats include,
zip: zip, medium range compression
gz: g-zip: good compression
Z: unix compression
Stuffit: A Mac compression format
• Some files, such as text, will become 1/10 of their original size.
2.5 Pulling all the Protocols and Formats Together With Browsers
• As you have already seen, the browser (ie, Netscape) helps pull these resources together.
• When we want to do things that are not part of the standard browser, we can use plug-ins.
• Plug-ins are small programs that can be used by Browsers to deal with different Protocols and Formats.
2.6 Other Stuff
2.6.1 Clients and Servers
• Some computers are set up to serve others as centers of activity, sort of like a campus library. Other computers are set up only as users, like bookshelves in a closed office. The server is open to all, while the private bookshelf has very limited access.
• A computer server will answer requests from other computers. These requests may be,
to get/put files with FTP
to send email
to provide web pages
• A client does not answer requests.
• Both clients and servers can generate requests.
• Any computer that is connected to the network Client or Server must be able to generate requests. You can see this as the Servers have more capabilities than the Clients.
• Microsoft and Apple computers have limited server capabilties, while unix and other computer types generally have more.
Windows 3.1: No client or server support without special software
Windows 95: No server support without special software
Windows NT: Limited server support with special versions
MacOS: Some server support with special software
Unix: Both client and server models built in
• In general you are best advised to use the main campus servers. But in some cases the extra effort to set up and maintain your own server may also be useful.
• To set up your own server machine you might,
1. Purchase a computer and network card. A Pentium class machine will actually provide more than enough power for a small web site.
2. Purchase of copy of Windows NT server version.
3. Choose a name for your computer that is easy to remember. An example is ‘artsite’.
4. Call the Information technology people on campus, and request an IP address. Also ask for the gateway number, netmask, and nameserver numbers. They will add your machine to the campus DNS so that others may find it by name (the number will always work if chosen properly).
5. Connect the computer to the network, then turn it on.
6. Install Windows NT, and when asked provide the network information. Indicate that web serving will be permitted.
7. Modify web pages as required.
• This is a programming language that is supported on most Internet based computers.
• These programs will run on any computer: there is no need for a Mac, PC and Unix version.
• Most users don’t need to program in Java, but the results can be used in your web pages
• Simple programs can be written as part of an html file that will add abilities to the HTML page.
• CGI (Common Gateway Interface) is a very popular technique to allow the html page on the client to run programs on the server.
• Typical examples of these include,
• There are major search engines on the Internet.
• You can also install local search engines for your site.
• This is a programming method proposed by Microsoft to reduce the success of Java: It has been part of the antitrust suit against Microsoft by the Justice Department.
• It will only work on IBM PC computers running the ‘Internet Explorer’ browser from Microsoft.
• One major advantage of ActiveX is that it allows users to take advantage of programs written for Windows machines.
• Note: Unless there is no choice avoid this technique. If similar capabilities are needed, use Java instead.
• Two good formats are,
GIF: well suited to limited color images: no loss in compression. Use these for line images, technical drawings, etc
JPG: well suited to photographs: image can be highly compressed with minimal distortion. Use these for photographs.
• Digital cameras will permit image capture and storage: images in JPG format are best.
• Scanners will capture images, but this is a poor alternative as the image sizes are larger and image quality is poorer
Photographs tend to become grainy when scanned.
Line drawings become blurred.
• Screen captures are also possible, but do these with a lower color resolution on the screen (256 color mode).
• These are not video, but moving drawings/cartoons.
• Animations are limited, but are best done with animated gif files.
• Other options include,
special plug-ins such as shockwave
• Streaming built into Netscape for real-time video.
• We can also get special plug-ins that will allow us to see video files,
MPEG very popular, good compression, and fault tolerant.
AVI popular on PC platforms, but limited drivers elsewhere.
• Real-time video conferencing is possible, but not yet practical.
• Sound files are poorly supported, and most require special plugins,
2.6.11 Other Program Files
• We can connect any type of non-standard computer file to our pages, such as a Microsoft Excel file ‘.xls’.
• To do this we need to,
1. Put the file in our web directory
2. Link it to one or more HTML pages
3. Have the system administrator add this as a MIME type to the system.
4. When you click on the link to the file in Netscape it will ask you to choose an application. For an excel file you would want to choose ‘\program files\office97\excel’. This will automatically start when you choose the file next time. If you did not do step 3, or did not choose an application you would be asked to save the file.
• This is an excellent way to extend the capabilities of a web browser.
2.6.12 Fancy Stuff
• Compact Discs (CDs) are becoming a common way to transfer information. These will allow you to store up to 650 MB of data. When used they look exactly like another disk drive that cannot be overwritten. To make a CD the writers cost about $400, and writable CDs can be purchased for about $1-2 each. It will take 30-60 minutes for a CD writer to create a CD that is completely filled.
2.7 Teaching With The Internet
• The impact that web based material has on the students is,
easy access to course note correction and additions.
easy access to ‘bulletin-board’ type information.
students can add their own assignments to the course notes.
software and application specific files can be easily downloaded by the students.
the students can have a copy of the lecture material, and so the lecture focus shifts from dictation, to discussion of the course content.
homework can be submitted and returned without leaving home.
• In general the students strongly favor the Web based approach, although there are a number of problems that face some of them,
different levels of computer support. Some students have no Internet access from home.
access problems in campus computer labs.
the learning curve: this is quickly decreasing.
• There are some strong benefits for the faculty member who plans to use the Web for course materials,
the preparation before each lecture is decreased.
each lecture can be more consistent, if the web pages are used for presentation.
software and files are easy to distribute.
paperless marking can be done by having students upload files to their accounts. The instructor can then download these files and use software (e.g. Word, Photoshop, MathCAD and Working Model) to mark and leave comments. These files are then uploaded to a private directory where the student can retrieve them.
homework submitted with software such as Mathcad forces students to be exact in their calculations. It makes it harder to be obtuse, verbose, or vague.
notices can be posted on the web, saving trips to a designated board.
individual students can be reached with email.
changes in the course notes can be easily distributed.
students can post their work publicly and compare to others.
• There are some additional demands placed on the instructor,
before the course is offered the first time the instructor must spend a large amount of time developing solid course materials.
support is needed from the department/faculty to provide needed release time and equipment support.
mistakes on-line can become very public.
the course may become less flexible after the beginning of the term.
• You can start small by developing materials for part of a course or a single lecture.
• Before the course starts you will probably want to follow a time line like that shown below.
• The approach to the lectures should generally follow the form below,
• Strategies for success include,
Know the software and hardware.
Keep a bit of ‘MTV’ style in mind. Videos, sounds and other moving things help.
Do a ‘dress rehearsal’ well before the first class: small details such as fonts can ruin all the other efforts. Ask somebody to sit through a short trial run.
Try to make computer use unavoidable for some aspects: If not some students will ‘get it from their friends’ and you never get good contact.
Provide a good tutorial guide for all software students use, and offer assistance when possible.
Try to avoid commiserating with students when they have software problems. They need your confidence. If necessary find the answer and get back to them.
Get full administrative support.
Give the students something to do during the class: discussions or drill problems.
Turn on the lights and solve problems on the board frequently, it will wake up students going to sleep in the dark.
Web Server: Your campus will have at least one web server, and this can acts as a useful place to leave files. Another (not recommended) alternative is to set up your own web server. I have set mine up using Linux (Unix for PCs) on a standard desktop computer, this can also be done using Windows NT (TM) produced by Microsoft. Between your files, and the students work, you should expect to fill tens of megabytes conservatively or up to gigabytes for large files and/or classes.
Faculty Computers: You will need at least one computer. A laptop is best, and can often be taken to the classroom. Networked desktop machines in the office and in the classroom can be set up with appropriate software.
Data Projector: If possible get a high quality data projector that will connect to your computer. If this is not possible, use an LCD panel on an overhead projector, this will appear a bit dark. Worst case use a computer to TV converter, this will be the least expensive, but the graphic quality is very poor. (in many classrooms and on rolling carts: ask IT)
Word Processor/Publishing Software: You will need a word processor of some description to prepare web pages. This is actually somewhat difficult for lecture material. The word processor typically needs to be able to include figures and possibly equations. The format used in this package must then be able to be converted to HTML. At the time of writing the variety of option is limited, but the market will soon be flooded. At present the best solution that I have been able to find is Adobe Framemaker. This runs on PCs, Macintosh, and Unix platforms.
Browser: There are a number of excellent browsers available today, but the two best are available from Netscape and Microsoft (use Netscape when possible). Both can be obtained at no charge under certain conditions. Either will do for the students, and this software can be used as a presentation tool in class. (www.netscape.com)
Application Software: I have used packages such as Working Model, and Mathcad to support lectures. Anybody using the browsers for course notes will need copies of application software to included files. These files will allow the notes to become interactive, visual, experimental, etc. This could include other software such as Photoshop for modifying pictures.
Digital Camera/Scanner: A scanner can be very useful for capturing images on paper. But when possible this should be discouraged. Scanned documents are very large, and can be very slow when downloaded for viewing. Scanned photographs also tend to have a poor quality. A very good option is to buy a digital camera that captures images directly to digital format. These cameras come in a variety of prices, but a good midrange camera can be purchased for $600 that will give good quality photographs. Within a short period of time these costs will drop quickly, and real time video capture will be an option. Other poor options include camcorders with image capture hardware in a PC. This gives grainy pictures or low resolution. (available from IT and in many departments)
• The computer based presentation can be quite similar to overheads, therefore a sequence that helps improve the attention level is,
1. Some overview that sets the reason and objective for the section. (a good place for pictures)
2. An overview of relevant theory.
3. A simple example problem: with solution and notes about steps, notations, etc.
4. A simple unsolved drill problem.
5. Additional notes on technique and methods.
6. An advanced problem with solution.
7. An unsolved complex problem, done on the board.
• The lecture style needs to be dynamic, some ideas are,
Use the computer to present new material, then turn on the lights and discuss or do problems on the board.
If the computer screen is in front of a whiteboard, pull up the screen, and add notes using the screen underneath.
Ask students questions about what was just covered.
Get the students to calculate numbers, write, draw, etc..
Say something ridiculous to get a response.
Tell a joke.
Walk into the seats.
Borrow something for an example.
2.7.3 On-Line Notes
• Typical tips for making on-line notes are,
have references that will automatically link to the reference source.
have different levels of material: the students can then skim the material they understand, and explore challenging topics.
use other media to explain topics.
allow links to fundamental materials for students needing review.
written text is bulky and hard to read, point form or highly condensed text is better.
the material should be cut up into small sections, a single printed page is a good size, but more or less can be used as required.
a good directory structure is needed to organize the information. This should be done before doing any large scale development of the Web site. Cut the information up and organize by major and minor topic areas. (don’t worry if these are not perfect, you can adjust this later when setting up tables of content.)
the need to worry about fonts and layout (e.g. pagination) is not an issue as the readers viewer will take care of these. But, each section/subsection should be in a separate file to decrease delays.
we can add links to other documents that allow direct connection to references. This frees us from having to fully explain every point (e.g. go straight to an earlier proof).
tables of contents can be used, as in normal books, but they can be broken into smaller parts.
when there are enough small segments of information, we can put together different books. Each of these can put the material in different sequences, or as reference. I typically produce one of these for each course.
a date must be added to sections. The document is living, and corrections and additions can be made frequently. The reader needs a date or version number to know when these changes have occurred.
various miscellaneous items need to be added. A set of icons are needed for navigating through the document (next, previous, up one level). A contact email address. An identifying icon that marks the page. A copyright notice is optional, but should appear on each web page.
line drawing figures convert well to Web format.
photographs can be added easily but are best left as links. Viewing documents with a large number of photographs on the page slows down viewing, and makes the document very large.
linking to video and sound can cause problems, as no format is supported universally.
linking to application files requires that the reader have specific application software (e.g. Mathcad or Photoshop).
we can add hypertext links to other sites outside of our documents, but these are highly unreliable, and so they may be separated into a separate file.
• Issues include,
password protection is possible when you don’t want notes to be shared publicly. Student then need to have the password to access the notes on-line.
2.7.4 On-Line Marking
• On-line marking requires the transmission of student work to the instructor, and back to the student.
• Work can be submitted and returned using,
email: student email files. These are marked and returned by email.
web server: students post solutions to the web. These files are marked and returned by email or put in a private student directory.
2.7.5 Web Pages
• Students are given web pages at the start of the term, and encouraged to use them quickly.
• This has turned out to be an excellent method for transmitting information, and it also allows students to build a portfolio.
• Students submit work by linking their homework to their page.
• The student controlled pages have lead to a great deal of ‘ownership’ and pride.
• On-line marking with the Web involves,
1. go to the students home page.
2. find the particular assignment to be marked.
3. select the file of interest.
4. the file is examined for technical detail, comments and a grade are added in red text.
5. the file is saved, and copied to the students directory.
6. the mark is recorded in a spreadsheet program.
• I use email, but not as an integral part of the course. If marking is done this way then it would become essential
• Many students use this as an alternative to finding me for simple questions.
• If you were to mark by email,
1. When the assignment is completed/due the student emails you with the assignment file attached. This might be a Word file containing an essay.
2. You receive the email, and open the attached file. You grade the file directly, and add comments. Comments can be put in a different font/color to make them stand out.
3 Record the grade in a spreadsheet.
4. email the marked file back to the student.
2.7.7 The Time-Line For My First On-Line Course (Fall 1996)
• These notes were made from a log of experiences with my first computer based course.
• Since then many improvements have been made (see PAD 168 as an example) by IT based on feedback: If you have any needs, talk to them.
Pre-August: Notes entered into computer.
Aug., 12: Notebook computer arrives.
Aug.,13: Notes handed to printer.
Aug.,20: Investigate computer projection equipment in assigned classrooms, the overhead projectors are only for TV, but there are 10baseT network sockets in rooms. There are data projectors in a locked hallway cabinet. Keys for cabinet are ordered.
Aug., 23: Start up software to test run, it. Results are OK.
Aug., 26: Classes start. The keys are not ready yet, I need to arrive early to ask somebody to unlock the closet. I test data projector, it only displays 640x480. The setup time was under five minutes. The last ten minutes of first lecture done with computer and data projector. When the lights are turned out the room is too dark to see paper (no side scatter of light as with overhead). The lights only go on in half of room. The trackpoint on the computer is very awkward to control scroll bars, etc. Even though part of the screen is chopped, it is mainly scrollbars. Using the word processor software, only half a printed page appears, and page breaks can fill a screen. The second section had windows with screens, and the light levels were fine.: Lesson Learned: do an early test run before the first lecture.
Aug.,28: Arrived ten minutes early to get cabinet unlocked and equipment set up. In the dark room I decided to use overhead projector pointed at wall for ambient light: seems to work well, but proper lighting would be better. Took a regular mouse (instead of trackpoint) to help control problems. Used working model to run a simulation, seemed to clarify conceptual difference between statics and dynamics.
Aug., 30: Settled on 10 minutes early as the expected pre-class preparation time. Noticed dark made some students sleepy. Ran entire lecture in dark, including questions. In second section I tried to do problems on board to parallel what was on the computer, had to remove fluorescent bulbs at front of room to get reasonable lighting. Show-of-hands survey indicated that; they liked not having to copy down notes: more time to think, no problems seeing screen, or following along. Projector cabinet key arrives today.: Lesson Learned: Be aware that the dark room puts students to sleep.
Sept., 4: Arrived a bit late, having to pick up the data projector cost lecture time. Students seemed a bit sluggish in dark, tried turning on lights to solve a problem on the board, this seemed to help a bit.: Lesson Learned: Change the mode of presentation to keep them active.
Sept., 6: The bulk of books, computer, etc. is somewhat annoying: needed to take the power supply because of the extended time (3 hours) of continuous lectures.
Sept., 9: The notebook power manager was shutting down the laptop every couple of minutes, went to lecture on blackboard. Took power supply to second lecture.
Sept., 13: Power manager acted up in first class, PC was almost unusable: Lesson Learned: decided to take power supply each time, or disable power manager software. Picked up digital camera Apple Quicktake 100: the camera was relatively easy to setup and use, but battery life was too short (<5 minutes) so the power supply was needed when downloading to computer. The camera took 8 or 32 pictures. The lower resolution of 320x240 was too poor for sharp detail, so the camera could really only hold 8 pictures.
Sept., 16: Web Site almost ready.
Sept., 17: Introduced students to Web pages, reception was good. Worked on getting web pages up, including hypertext links to gifs. This was only possible by tricking WebWorks software into passing it through without converting characters. Lesson Learned: plan for the document conversion process, the software available still limits abilities. Made some graphics to go with pages: gives the pages a polished look. Took pictures with digital camera: it was very sensitive to light levels, and distance/close detail was blurry.
Sept., 18: Presented in class using Netscape off local disk files: increased font sizes, and DPI for gifs (up to 120 from 74) to better fill screen. The text was more viewable on screen. By contrast the normal screen font is too small. Lesson Learned: Use Netscape instead of Framemaker to present.
Sept., 20: Presented with netscape again, this time using the network and the Web site: this ran well, but as the morning progressed the transfer rates slowed, especially as the hour approached.
Sept., 23: Presented off local disk again, ran much faster. Added course info to web site, including sample problems and syllabus. Prepared first midterm, and had answers prepared, and ready to post after test.
Sept.,24: Got camera and started taking more pictures. Got copies of Working Model quick start guide, plan to give to students tomorrow, and will suggest a problem to try next week.
Sept., 25: Demonstrated Working model in class by building a ball between wedges, a robot, and a block hung by two cables. Also gave out tutorial manual, and indicated that next week some problems will be assigned to be done on working model. Student reaction was ‘WOW’. Lesson Learned: Visual impact should be used whenever possible.
Sept., 26: Fixing up things, but realize that pictures collected in future must be to fulfill need. there are too many pictures to take, and not enough disk space. Got some email questions about textbook problems. Did not have textbook. It would have been nice if all questions were on-line for easy reference, and so that notes could be added to the problems.
Sept., 27: Exam day. Showed mpeg movie of Tacoma Narrows bridge: a good visual part. More videos would be great. Solutions posted on line, and students seemed to have them printed shortly after the exam. Lesson Learned: When possible post exam solutions on-line.
Sept., 29: Some Working Model examples created for classes this week. Misalignment was a small problem: but more practice expected to reduce problems. A 3D problem is not possible using the current version.
Sept., 30: Presented in class using Netscape only. This included working model links, and photographs. The models were Static, and a loss of interest was apparent. First working model assignment discussed as bonus. Student interest picks up. The lab version is not working well, (it later turns out that some computer labs don’t support the package) I load a copy of the demo software to my website for local download. Find transcription error in the exam solution posted on-line, fix problem on-line and mention to students. Lesson Learned: Even though we can change things on line, if it is printed mistakes are permanent. Lesson Learned: Just because your computer will do it doesn’t mean the students computers will.
Oct., 4: The network locked up, had to present using framemaker: considered keeping copy of course on hard drive. Lesson Learned: The Internet is not reliable, have alternate solutions. SVGA to NTSC converter arrived: tried in class, very poor with high resolution graphics. Went back to data projector. Other problems, cables too short, and s-video connector only on ceiling mounted projector. Good rule of thumb, count on a loss of 50% of resolution, and avoid thin lines.
Oct., 7: tried using the SVGA converter in class again, very poor appearance, but as okay with larger fonts, but the unit seemed to shut down after a few minutes.
Oct., 11: Had classes, and then working model contest at the end. This seems to have set a fire in some students. Most were impressed. In general the interest level was higher in the smaller class. One very good technique with the data projector is too project the image onto a whiteboard and draw over the image using markers. This allows the students to add/refer to their notes.
Oct., 18: A very effective use of working model to show the students slip/tip case for a block, and then calculate to verify.
Oct., 22: Tried a test of SVGA to TV converter in class with large fonts. The students seemed to be happy with presentation styles, and agreed to an in class trial. Helvetica font seemed to be perceived as slightly better, by show of hands. Took a while and changed some of the notes to helvetica, and posted to net. Put some problem solutions on the net that were missing in the text.
Oct., 23: Went to present in class with SVGA to TV and the network was misbehaving, so could not connect to site. The network was down today, so the students could not get access to the web pages, and I could not update.
Oct., 25: Data projector did not work in first class, used the board instead. In second class found that the data projector was set for the wrong input. Lesson Learned: Even when the equipment works well, figure out why it is working well just in case. In the conversion process the multiplication sign was changed to a ‘yen’ sign. I also noted that in printing some of the equations were not printed properly, but the students were able to copy off the screen (or could use the web pages).
Oct., 28: Data projector stopped working, and sent to get repaired.presented on board in class.
Oct., 29: Presented in morning class using SVGA to TV converter. Did not seem to cause many problems.
Oct., 30: Exam day. Did not have time to put exam solutions on net.
Nov., 1: Returned exams: solutions not yet on net, but meeting students face to face to return papers (one at a time). Did the first survey in class. Used the SVGA to TV converter to present, the second class was seeing it for the first time, and complained of the poor quality.
Nov., 4: Presented in class as normal using board mainly. projector is still missing.
Nov., 5: Computer did not work.
Nov., 6: Data projector did not work again. Will use computer and projector next class.
Nov., 8: Data projector fixed, lecture proceeded as normal.