Ideas….

Yesterday I went to the LITA sponsered talk about OAI-ORE. I went because I wanted to see the man (the myth, the legend) behind SFX and OpenURL, as well as bX, Ex Libris’ new recommender service.  Basically, if it weren’t for Herbert Van de Sompel’s brain I wouldn’t have had a job for the two years prior to working at Wheaton, so you know…I had to go.

So anyway, on to the real meat of the post.  What is ORE?  Well that’s a great question; let’s see if I can sum up what I’ve learned.

First, Herbert did a quick crash course on what RDF was.  It consisted of this:

• resources exist at a particular URI
• RDF is about explaining resources
• there are things called RDF triples, they consist of a subject, predicate, and object
• if you don’t have a URI for a resource you can have something called a literal

Below is an image of RDF triples:

Kind of an abstract idea, but if you’re really interested in learning more check out W3C’s page on RDF, perhaps reading the RDF primer first (of course I recommend this, but I have yet to do that myself).

Ok so now that we have a basic understanding of RDF we can move on and gain a basic understanding of ORE (supposedly).

The ORE Primer states that:

Open Archives Initiative Object Reuse and Exchange (OAI-ORE) defines standards for the description and exchange of aggregations of Web resources.

Brilliant, so now instead of just describing one resource we can aggregate resources together, but then what?  OAI-ORE uses the same http 303 redirect guidelines that linked data does to redirect users to something called a resource map.  This map describes how the different resources in the aggregation are related to one another.

What’s great about the resource map is that it lives in what Herbert calls the two web worlds (web 2.0 and the semantic web).  The resource map can be written in Atom XML, RDF, and RDFa (RDFa is like RDF except in XHTML rather than XML).

So now we can have aggregations of resources in a machine readable map rather than sitting out there as seperate resources seemingly unrelated to one another.

Herbet went on to say that Dr. Robert Sanderson at the University of Liverpool actually went through and created resource maps for everything in JSTOR.  You can find out a little more about this project via this Code4Lib listserv posting.

So that’s OAI-ORE in a nutshell.  A very small, simple minded nutshell.

Friday I decided to be a complete and utter geek and install Apache Tomcat on my Mac.  I know, I know you’re asking me “But Rosalyn Apache comes with a Mac, why do you need Tomcat?”  Well that’s a good question.  And the answer is I wanted to install XTF which is an XML publishing tool developed by CDL (California Digital Library), and XTF requires that you use Tomcat in order to run it (or you can use Resin…but I’m an Apache fan).

So now you’re thinking, “How did you do it?”  I wish I could have thought it up on my own, but saddly I didn’t.  I looked at a few pages and then finally settled on Basil Borque’s section (under Update 2006) on this wiki page: http://wiki.apache.org/tomcat/TomcatOnMacOS.  Bravo to Basil for posting the directions.  I didn’t bother with the firewall though because my laptop is behind a firewall by default.  Also I wanted to still run Apache so I left Tomcat on its default port 8080.

Once I got Tomcat up and running, I then moved on to XTF.  This process was ridiculously easy.  CDL has wonderful XTF installation directions on the SourceForge XTF Wiki.  If you’re on Wheaton’s Campus (and my computer is currently connected to the internet) you can view XTF here.

To create a schema you can use Roma. This gives you a graphical interface that allows you to include or exclude elements, include or exclude attributes, and constrain values for attribute values.

A few pointers for using Roma…

• hit submit every time you make a change. there is a bug that sometimes it doesn’t look like you’ve saved your changes, but in reality you have. and if you don’t hit save, then you’ve definitely not saved your work.
• give your schema a name that will help you understand what its purpose is for. you can also supply a description of its purpose. one idea is to create a schema and then come back later and modify it as you delve deeper into analyzing your text.
• save your schema as Relax NG schema (compact syntax). this files gives your xml code a place to go to double check that you are organizing your data properly.
• save your documentation in html so that you can read what the elements and attributes you can use in your customized schema are.
• save your customization (aka the ODD file). this is the file that creates the schema (ie .rnc file). if you have any problems with your schema you might want to look at the ODD file to make sure the changes you made are properly reflected in the schema document.

creating a schema allows your coders to reduce the options they can choose from and hopefully reduce the amount of mistakes they can possibly make.