What are the advantages of using an OWL based ontology and a reasoner over a using a relational database?

It depends upon your application. If you are building a application that uses semantic web search or querying features or an application enabling complex user tagging across multiple taxonomies such a system might speed development immensely. If you are not creating such an application you should stay away from this technology and stick with relational databases.

The advantage is in how computers use the information. Computers can't speak English. A human knows that words like 'horse', 'stallion', 'foal', and 'gelding' are semantically linked - they're not synonyms, but they're definitely related.

The machine has no idea. (In fact, if it's using a stemmer and not a dictionary, it will identify 'geld' as the base word of 'gelding' and then the person is lost too! ) So semantics are important.

The idea of OWL, and also RDF (Resource Description Framework: it was born as a metadata standard), is to provide the machine with a bit of semantic context (an ontology is a system of meaning, after all). So the advantage of OWL is creating better machine management of information, and hopefully descriptions that will fare better in the Big Wide Web and last maybe a couple of years longer. If your system is internal to an organisation, you maybe won't need it.It you've got something you want to send out into the world, OWL or RDF will (probably) be a better bet in the long term.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.