23 replies to this topic

[Harry Barton]

I need some help woth hypermedia, got a prelim for it tommorow!!

I only have this unit as a prelim tommorow as i did the other stuff at normal prelim time
hope someone can help as the stuff isnt the most exciting or interesting so i havent learned it very well

[Harry Barton]

i just noticed my teacher is an idiot, computer application software looks much easier

i could have passed that with my own knowledge!

[George]

Yes, I done Computer Application Software last year and found it quite straightforward. Sorry, I can't help with hypermedia

Anyway, I hope you do well in the prelim!

[Harry Barton]

this is pretty bad as i got an A for the prelim and now i think hypermedia is going to damage my grade

[Allan]

I did Hypermedia, got 28/30 in that section of the prelim

So if you've any questions, just ask

[Harry Barton]

lol well i just tried a past paper and couldnt answer anything

it seems my teacher hasnt taught me anything

can you give me some rough info that could be very valuable to me to get me through this

that's if you're still online

[Ally]

Hey!

Help Required: Is the Hypermedia prelim based on the 2003 exam, like the normal prelim was?

Are there any topics which are essential to revise?

Is it me, or is the Hypermedia work just sooo dull...

I just can't seem to get the useful facts stuck in my head...

Any tips?

Thanks

[Allan]

Sorry this'll be too late to help...but just for the final here's some tips for both of you

Ally, our prelim was made up from a selection of different years 'Perfect Papers' prelim papers so I can't really say what yours will be like.

Basically for hypermedia you've got the basics:

• the basic structures that make up a hypermedia system; i.e. nodes (storage locators for related items of information), anchors (area of a node which is the end point/source of a link) and links (these connect nodes together) - for a system to be a hypermedia system it must be made up of these 3 basic structures
  
• searching a hypermedia system with natural language queries (english syntax, form of a question) and boolean queries (AND, NOT, OR; stricter syntax); search engines (these move across the web requesting documents from servers and building up an index of the pages they visit, then compares users search requests with the pages in the index)
  
• navigating a hypermedia system which is the process of moving through the system by following links from nodes to node; navigational aids e.g. backtracking, history, bookmarks etc and how they work and how they can aid navigation
  
• navigation strategies - breadth first where prudent users explore the neighbourhood of the node before moving further away; depth first where daring users jump straight into the hypertext and move further and further away from the home page by following links forward and not backing out till they reach a node with outgoing links
  
• how a system could be user friendly/well structured - e.g. no dead ends, consistent navigation, options easy to find etc
  
• generations - 1st/2nd/3rd and their characteristics and examples of them (in HSDU notes)
  
• user interfaces - text/windows/frames and their characteristics and why they may be suited to specific uses e.g. text interface for a report...
  
• combining a hypermedia system with a relational database - so that any data is held within the relational database (and why e.g. improved speed of access, less data redundancy), stored in lots of separate entities for different files, then the front end of the system is a website (the hypermedia product) which provides the user with a familiar interface to transform the data held in the relational database into the information on the website for the user to see

Then you've got the applications, developments and stimuli:

• current applications - reference materials, online documents, learning systems, collaborative work; these are all covered in the HSDU notes and you should be able to describe how they are used, why they are used, pros/cons etc
  
• contemporary developments - virtual reality (desktop and immersive), interactive TV, software robots, XML, java; again the notes cover these and some details and characteristics of these may be asked about
  
• stimuli to developments - e-commerce, teleworking, intranets, advanced data structures, collaborative systems, distributed systems; make sure you can describe the uses and characteristics, pros/cons of all these

The trickiest bit is the data models:

• dexter - the 3 layers, anchoring, atomic/composite/link components, presentation specifications, resolver/accessor function, specifiers, instantiations, end point specifications, sessions, run time resolver function
  
• amsterdam - how it extends dexter, parallel/choice components, coarse/fine grained synchronisation, synchronisation arcs, channels
  
• WWW - uses, searching/navigating, Uniform Resource Locators (URLs) [the HSDU notes call it a Universal Resource Locator but the correct name is UNIFORM], problems with the web (e.g. lack of flexibility, getting 'lost', too much info, limitations of HTML, unidrectional links), web browsers

The models are always a big part of the hypermedia section and I've just summed them up there without much detail. You need to know a lot more than the lists I've put there. You need to know definitions, uses, pros/cons, examples and be able to relate them to the given scenario.

If you've any questions, just let me know

[Ally]

Thanks a lot for that!

It's really helpful.

..yeah , do you know what the difference between coarse/fined grained synchronisation as I don't understand the notes. The explanation they give doesn't make sense to me.

Could you please help me?

Thanks


Ally

[Allan]

hmmm that's a bit unclear, I don't quite understand that myself!

but here's my interpretation of it:

the HSDU notes have two slightly different definitions of them:

• coarse grained synchronisation - used to synchronise different components e.g. a video and a sound clip; used to ensure that the audio and video components remain active for the correct duration
  
• fine grained synchronisation - used for synchronisation between components e.g. 2 or 3 sound clips played one after another; used to ensure the 2nd audio or video component starts the right length of time after the first

So what I guess it means is that coarse grained involves 2 different types of media componenets and getting them to play together at the same time. So it's like if you've got a video, ur gonna want the sound to play at the exact same time as the video.

And then fine grained involves getting different media components (which could be of different types) to play one after another. So if you've got 2 video files you want to play then you don't want the 2nd one starting half way through the 1st one. So fine grained synchronisation would make sure the 2nd video started AFTER the 1st one.

So that's how I interpret it, which I can't guarantee you is right coz Dexter & Amsterdam confuse me, they'd confuse anyone! To be honest, ur best bet is to just learn the definitions in the bullets above from the notes, even if you don't understand them.

[Ally]

Hey!

Does anyone know how the resolver function uses end-point specifications???

I don't understand the question, let alone the answer!

Ally

[Allan]

I don't really get that question either, but our teacher read out the answer for that question:

"The resolver function takes the end point specification (which is the component ID and the anchor ID from within the component) and finds them within the link component held in the storage layer. They find the details of the link component in order to find the location of other components linked to it."

[Ally]

Yeah it was a really tricky question.

You know for the commercial reason of why the hypermedia is being built , is it just because it saves money?

Ally

[Allan]

The commercial reasons are under the stimuli to developments of the HSDU notes.

I'd probably say to compete in a global market using e-commerce.

[Ally]

Could you please tell me the pro's and con's related to the use of HTML.


Thanks


Ally

[Allan]

Hmmm can't think of many advantages of HTML that we've been taught......looking at the exam board's notes they've got that HTML's simplicty allows users to gain an understanding of it and be able to use it in a short space of time.

There's more focuss on disadvantages of it:

• its simplicity places major constraints on the expresiveness of the resulting hypertext
  
• HTML has undergone many chances, some of which have been ill considered and inappropriate
  
• many users are currently unaware of the state of the language
  
• users and developers fail to adhere to a single standard which leads to incompatabilities and inconsistencies which only serve to reduce the effectiveness of the WWW

The main disadvantage I would say is that links are unidirectional, so they can only travel forward. The disadvatages of unidreictional links in the notes aren't exactly that easy to understand but if you learn them up it'll be no problem:

• difficult to maintain documents as there is no way of finding all the documents that point on a certain document given only the destination document
  
• the physical location of documents is hidden in URLs so dangling results can result from moving nodes from one place to another
  
• there is no way of informing all links of a change in the destination address

Hope that helps

[jillian]

Can anyone help me i am looking for clear straight forward notes on hypermedia as i do not have clue about it!


Thanks

Jillian

[Ally]

Hi

I have typed out some notes for Hypermedia and am finding them useful. They're nice and succint (I hope so anyway!) unlike the HDSU notes.

If you would like them just give me your email address and I'll email them to you.

[Malcolm2]

Does anyone have any easy revision notes/techniques for the Dexter and Amsterdam model?
Thanks

[Malcolm]

i do, also wondering if anyone has any notes on copyright and legality acts