4 January 2003 Archives

I don’t watch much commercial TV, so the ad I saw may be old to most of you. The TV commercial showed a group of men having lunch at a diner, one of whom is complaining about taxes. His companions are obviously uncomfortable with the talk, and a couple in the booth behind the man looked over at him in fear as they quickly leave the booth.

His friends tell him:

“Calm down.”

“Do you want them to ruin your life?”

“They can do that you know.”

At the end of the commercial the words:

Freedom. Appreciate it. Cherish it. Protect it.

The ad was sponsored by the Ad Council — the consortium of US advertisers that perform voluntary ad campaigns.

At first, I was pleased by the ad, thinking that here is a mainstream organization warning Americans what’s at risk if they continue to give up freedoms in the name of ‘safety’. That was before I explored the Freedom campaign at the Ad Council web site.

According to the Council web page:

Developed following the tragedies of September 11th, the Ad Council’s Campaign for Freedom is an unprecedented volunteer effort from the advertising industry. The initiative is designed to assist Americans during the war on terrorism through the development of timely and relevant PSAs. This first round of PSAs has been created to celebrate our nation’s freedom and remind Americans about the importance of freedom and the need to protect it for future generations. According to research, Americans are looking for messages that will inform, involve and inspire them during the war on terrorism. (emphasis added) This inspirational campaign is advertising’s gift to America. All of the ads conclude with the powerful tagline, “Freedom. Appreciate it. Cherish it. Protect it.”

I watched the TV commercials (all available at the web site) as a man is arrested for delivering newspapers, another for asking for forbidden books in a library, and church members attending services secretly. All the ads are intended to ‘inform’ the American public about what will happen if we don’t continue to support the war on Terror. All horrifyingly demonstrating the reality of what is happening to this country because of the war on terror.

The whole art consists of doing this so skillfully that everyone will be convinced that the fact is real, the process necessary, the necessity correct, etc. But since propaganda is not and cannot be the necessity in itself, since its function,
like the poster, consists in attracting the attention of the crowd, and not in educating those who are already educated or who are striving after education and knowledge, its effect for the most part must be aimed at the emotions and only to a very limited degree at the so-called intellect.

Adolf Hitler, “Mein Kampf

Next week I’m delivering to my editor the complete first draft of “Practical RDF” for O’Reilly. Yeah, finally. No one has seen the complete TOC, including the tools, APIs and whatever used in the book and I thought I would provide a heads up before the book is released for public review.

If you’re interested, the TOC is duplicated below. If you have concerns about the technology used, or are curious as to why I’m covering one tool over another, or suggestions about tools/apis/topics you feel I should have covered, please leave a comment or send me an email.

Once the book has had a look over by my editor, I’ll be posting OpenOffice versions of each chapter for chapter by chapter review at http://rdf.burningbird.net.

The book ended up featuring over 50 different tools and APIs, in seven different languages (Perl, PHP, Python, C, LISP, Java, C#, and even Javascript), on three different databases; most of the APIs and tools are currently in alpha/beta state, not to mention the RDF spec itself, now heading towards last call. This was a challenging and rather frustrating experience at times.

Grr.

But, most of the tools and APIs were freely given and open source, supported by people who want nothing more than to provide nifty technologies for people to use.

Grr-eat.

TOC:

Chapter 1. Introduction
This chapter will introduce the book, as well as provide a brief history of RDF including current efforts as of the date the first draft of the book.

What exactly is RDF?
A Brief History
RDF and the Semantic Web
Current Specification Efforts
The RDF Specifications
When to use and not use RDF
RDF Controversies
Related Technologies
The RDF Primer

Chapter 2. RDF: Heart and Soul
Focuses on the Concepts and Semantics specifications

The Search for Knowledge
The RDF Triple
The RDF Graph
The URI
RDF Serialization: N-Triples
Datatypes
Talking RDF: Lingo and Vocabulary
Sub-Graphs
Graph and Not Ground
Entailment
Equality
Assertions

Chapter 3. Basics of RDF/XML
The major elements of the RDF syntax are introduced and discussed. Covers the syntax and test cases docs

Serializing RDF to XML
Nodes
Stripped Syntax
Properties
URIs, Qnames, and Abbreviations
The Type Property
RDF Blank Nodes
More on RDF Data Types
RDF Shortcuts
The RDF Test Cases

Chapter 4. Specialized RDF Relationships: Reification, Collections, and Containers
More complex constructs with some semantic challenges.

RDF Containers
Basic Container syntax
Typed node emulation
RDF Collections
What Containers and Collections ‘mean’
Reified Statements
An Example of Reification
The Necessity of Reification and Higher-Order Statements
A Shorthand Reification Syntax
Why Big Ugly?
Why Reify?

Chapter 5 Important concepts from the RDF Vocabulary
The RDF Schema provides the roadmap to creating an RDF vocabulary. The “rules” are covered, with examples to clarify the more complex topics.

RDF Schema: Defining the Metadata
Metadata’s Role in Existing Applications
RDF Schema: Metadata Repository
Core RDF Schema Elements
Overview of the RDF Core Classes
Demonstrations of the RDF Core Classes
Refining RDF Vocabularies with Constraints
RDF Schema Alternatives

Chapter 6. Defining RDF Data Schemas
This chapter provides coverage of defining a custom vocabulary for RDF. Discussion will also cover PICS, as an example, as well as other examples.

What do we mean by Vocabulary
Defining the Vocabulary Business and Scope
Defining the Vocabulary Elements
The PostCon Elements
Prototyping the Vocabulary
Adding in Repeating Values and a container
Formalizing the Vocabulary with RDFS
Another Example: The Dublin Core
An overview of the Dublin Core MetaData Element Set
Dublin Core in RDF/XML
The Qualified Dublin Core elements
Mixing Vocabularies
Using DC-dot to generate DC RDF
When Precision isn’t enough

Chapter 7. Ontologies: RDF Business Models
Why Ontology?
DAML+OIL
RDF and OWL

Section II – RDF Tools
Now that we know what it is, how can we work with it?

Chapter 8. Merging RDF with Other Technologies
Using RDF with other applications.

RDF and Links
RDF and SOAP
Generating RDF with XSLT
RDF and UML
RDF and SVG

Chapter 9. Editing, Parsing, Generating, Converting, and Browsing RDF
Browsers
BrownSauce
Parsers
ARP
Raptor RDF/XML Parser
ICS-FORTH Validating RDF Parser
Javascript RDF Parser
Wilbur
Editors
SMORE — Semantic Markup, Ontology, and RDF Editor
RDF Editor written in Java
Converters
Grove’s ConvertToRDF
Convert RDF to iCalendar (Dan Connolly) – RDF Calendar task force
DMOZ RDF Parser for MySQL

Chapter 10. Jena: A Java-Based RDF API
Overview of the Classes
The Underlying Parser
The Model
The Query
The Iterators
DAML+OIL
Creating and Serializing a model
Very Quick Simple Look
Encapsulating the Vocabulary in a Java Wrapper Class
Adding in more complex structures
Creating a Typed node
Creating a container
Parsing and Querying an RDF Document
Just doing a basic dump
Accessing specific values
In Memory versus Persistent Memory Model Storage
A Brief look at DAML+OIL in Jena

Chapter 11 RDF and the Three P’s

RDF/XML and Perl
Ginger Alliance PerlRDF
Model Persistence and Basic Querying
Serializing RDF/XML
Examining the Schema
RDFStore
The PHP XML RDF Classes
RDF-API
Class Overview
Creating an RDF Model
Parsing and Querying an RDF Model
PHP Classes for XML
Class overview
Rdql
Persistent RDF – rdql db
Python Support
RDFlib
Building a basic Model and Serializing
Parsing a model and queries
TripleStore and ZODB

Chapter 12 Querying RDF: RDF as Data
Basic relational syntax of RDF query languages
Querying with Jena
The Query Language
RDF Query-o-Matic
Querying with PHP
The Query Language
RDF Query-o-Matic light
Inkling–Querying RDF Data using SquishQL
Sesame
RDF Server (rdftp)
Versa RDF Querying Language

Chapter 13. A Brief look at other RDF Application Environments
Whatever works with XML, works with RDF/XML
Overview of Redland — a multi-language -based RDF Framework
Working with the Redland Framework
Redland’s language du jour – C
Using the Language APIs
Perl and Python
Redfoot
RDF and NET
C# RDF Parser
4Suite

Section III – RDF Goes to Work
We know what it is, we know how to use it, now list some of the uses.

Chapter 14. Subscription and Aggregation with RDF/RSS (RSS 1.0)
This chapter focuses on RSS, including how to expose content, including exposing content through userland, other sources. Chapter also covers Meerkat.

RSS: A quick History
RSS 1.0: A quick introduction
A Detailed Look at the Specification
Channel
Title, Link, Description
Items
Image
Textinput
Item
Extending the Specification through Modules
The RSS Modules
Core: Dublin Core, Syndication, Content
Extended
Brief look at RDF/RSS Aggregators
AmphetaDesk
Meerkat
Aggregating on a Mac
Creating your own RDF/RSS Content
(RDF/RSS isn’t only for news feeds)
Build your own RDF/RSS Consumer
PHP – using an XML API
Python – using an RDF API
Java – using a specialized RSS API
Perl – Ditto
Validating and Converting to RDF/RSS

Chapter 15. Mozilla: User Interface Development with XUL and RDF
Covers Mozilla’s use of RDF to process template data within XUL. Strong enough and significant enough to leave as separate chapter.
The Concepts behind XUL
A Brief Review of the XUL User Interfaces
Dynamic Table of Contents using XUL/RDF
Nested TOC Data

Chap 16. A World of Other Uses
FOAF: Friend-of-a-Friend
DMOZ Directory Outputs and the DMOZ parser
RDF Gateway, a commercial RDF Database
Chandler: RDF within an Open Source PIM
RDF and Adobe: XMP
Creative Commons license
Tucana KnowledgeStore (TKS)
A look at the RDF projects underway at Sourceforge

Appendix A. A Detailed Look at the RDF Grammar

Get permission from W3C to duplicate the RDF Grammar and productions

Appendix B. RDF Resources

URLs and notes to as many RDF resources as we can scrape together