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Trond Pettersen on Web Development and Topic Maps

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Category: Semantic Web

Web Application Development with Ontopia – 3. Creating the JSPs

Happy New Year 2010

After a busy December month, the Christmas vacation finally gave me some room to concentrate on what really matters.

Here’s my third blog post on building web apps with Ontopia. A bit late – I had hoped to have it out before Christmas – but at least I made it within January 01 2010 … have a good one!

Getting to the Point

This blog post is part of a series on Web Application Development with Ontopia.

  1. Part 1: Installation & Requirements
  2. Part 2: Creating the Database
  3. Part 3: Creating the JSPs

In Part 2 of this series on building web applications with Ontopia we had a look at how to set up an application’s domain model using Ontopoly.

This post discusses how to go about building a custom web interface to present the data.
Read the full article »

Web Application Development with Ontopia – 2. Creating the Database

Intro

This blog post is part of a series on Web Application Development with Ontopia.

  1. Part 1: Installation & Requirements
  2. Part 2: Creating the Database
  3. Part 3: Creating the JSPs

In part 1, we looked at how to set up Ontopia. We also described the application that we intend to build (a blog) and what we need to develop in order to achieve our goal.

This time we’ll look at how to set up the “database schema” and create new blog posts by using Ontopia’s web interface. The resulting topic map can be browsed here.

Read the full article »

Web Application Development with Ontopia – 1. Installation & Requirements

Introduction

Ontopia is an Open Source application that lets you create, manipulate and navigate information represented in topic maps. It’s also a toolbox for building all sorts of applications. Among the advantages of topic maps driven applications are enhanced navigation and search capabilities.

Ever since Ontopia went Open Source earlier this year, I’ve wanted to give an example of how easy it is to build a web application on top of it.

Through the next couple of blog posts, I’ll try to show exactly how easy this is – and I promise to leave out the unnecessary talk (wont discuss Topic Maps, for instance).

First I’ll “reveal” how to set up and start Ontopia. As this requires very little typing on my part, I’ll quickly move on to discuss what our goal is. Then we’ll have a look at the required data model, before pointing out the kinds of views that our application needs to support — and how to lay this out. Afterwards, we create the limited amount of code needed to get everything up and running. Last, we deploy.

All code will be available for download :)
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Berners-Lee excited about data.gov and the rise of the Semantic Web

DC-X

Google Alerts recently notified me of Digital Collection, a German supplier of software for managing and research of digital information, which has created a topic maps based tool for news monitoring, research, archiving, workflows and now content creation called DC-X.

From the company’s blog entry:

The benefits of treating thesaurus and list terms as topics in a topic map:

  • Built-in support for multiple names, which we’re using to store translations for terms: All lists and thesauri can now be multi-lingual.
  • Class/instance relationship between terms; the “City” list is itself a topic, “Hamburg” and “Oslo” are instances of the “City” topic. This way an unlimited number of lists or thesauri can co-exist. Terms can even belong to multiple lists.
  • Arbitrary relations between terms: A thesaurus hierarchy is modeled using associations like “broader/narrower” or “synonym/preferred term”. Geographic hierarchies can use “part/whole” associations.
  • External identifier URIs can be specified for any term, so metadata can be mapped to metadata of other software using RDF, or anything else that points to the same URI.
  • Custom metadata can be attached to any term. We’ll use this for thesaurus “scope notes”, geo coordinates for cities etc.

They also mention that it is implemented based on XTM, why they chose not to use RDF, how the tool can be used, as well as plans for implementing a topic map browser and editor.

Alexander Johannesen’s Event Model Ontology

While blogging I might as well be the first one (?) to link to Alexander Johannesen’s “Missing ontological serinity in the world of software systems architecture” and “What event model ontology?:)

Shakespeare Topic Map

Back when I was in the university I took an undergraduate subject called Web programming. As part of that class, each student had to build a web site presenting the Shakespeare plays in a given format. The source was a bunch of XML documents.

Building the site using PHP and SAX parsing was fun enough at the time, but even though the XTM 1.0 specification mentions #play, #shakespeare and #written-by, I can’t recall ever seeing a topic map enabled site of the Shakespeare plays.

I therefore thought that it’d be fun to transform the Shakespeare XMLs into a topic map and publish it through a web site built on top of Ontopia.

I’m just putting the front end together piece by piece (15 mins here and 15 mins there :/ – currently not very usable).

The current (draft) version of the topic map is available for export (~23 MB LTM, ~133 MB XTM 2.0). This can also be browsed with Omnigator. If you observe any major flaws, feel free to leave a comment below :)

Topic Maps in May: Ontopia & Subj3ct

Ontopia

The Ontopia project has had it’s “kick-off” meeting, which I unfortunately could not attend, and set up a blog at http://ontopia.wordpress.com/, with mailing list at http://groups.google.com/group/ontopia. Awesome.

Subj3ct

Back in May, NetworkedPlanet launched Subj3ct.com. I quote: Subj3ct provides the technology and services to enable Web 3.0 applications to define and exchange subject definitions.

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