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Re: Is there any logical conflict between the semantics in SW and that in SWS ?

From: Bijan Parsia <bparsia@isr.umd.edu>
Date: Sun, 27 Nov 2005 13:44:55 -0500
Message-Id: <ff6203f93adc5215d12ca90b3c47c661@isr.umd.edu>
Cc: SWS-IG <public-sws-ig@w3.org>
To: "Shi, Xuan" <xshi@GEO.WVU.edu>

On Nov 27, 2005, at 1:12 PM, Shi, Xuan wrote:
[snip]
> We may have certain agreement on our discussion if you would read our  
> paper
> "Rebuilding the Semantic Web Service Architecture" at the Web site:
> http://sunsite.informatik.rwth-aachen.de/Publications/CEUR-WS//Vol 
> -140/ item
> #3. The examples discussed in this paper demonstrated that machines  
> have the
> ability to correctly intepret services WITHOUT human (programmer)
> intervention, i.e. automatic service discovery, matchmaking,  
> composition,
> and invocation. By adding or removing the Web services in the listbox  
> in
> that example, computer can "understand" whether it can perform certain  
> tasks
> and/or dynamically invoke the required service (if exists) for certain
> purpose.

I don't see how this supports any of your stronger conclusions, esp.  
about sematnic chaos. But let's look at your paper;

page 3:

"Semantics of web services are tied to names given to functions and  
arguments in  WSDL. They are not derived from any standardized  
ontology."

What would it be to derive them from a standardized ontology? Or just  
from an ontology? Do you mean that there should be a prior ontology of  
services that we align our descriptions with? Who curates this? Why  
only one? Why one grand one? Why a prior or standardized one? Am I  
reading too much into this sentence?

" This fact is a source  for confusion, as meaning of the services has  
to be guessed. "

I don't understand this *at all*. So I name a service and I type it's  
arguments. I write down these facts in a natural language for the  
users. To use my service, they must read my documentation and act  
accordingly. It's error prone and a PITA. So, I express these facts in  
an interface definition language like, oh, say, WSDL. It does the job I  
want it to do, e.g., generate stubs for usage. Now I want to make my  
service more broadly accessible and I want to document it better. So I  
write a description in natural language including all sorts of yummy  
stuff, like what the purpose is, how much we charge for it, the fact  
that it requires prior registration and a credit card number, etc. Ok,  
that's nice. But I have the same problem as before: It requires a lot  
of human intervention even on the crappy bits. So, I try to express at  
least some of these facts in a formal language, say OWL, but it could  
be F-Logic, or whatever. I need a bit more than OWL alone, since I want  
to express preconditions and effects, but ok. I do this. Other people  
have a better time dealing with my stuff if I connect my description to  
other people's, typically via some common ontologies.

The only thing I see (from a quick skim) is that you want homogenous  
invocations, a la REST, with elaborate semantics embedded in the  
messages exchanged (self describing). Well, ok, this is hardly a  
revolution. But it has absolutely no traction whatsoever. So it seems  
like a non-starter to me.


> However, remember Uschold implied that what and how machine can process
> depends on what and how human designs the procedures. To enable such
> automation in semantic Web services, we need agreements or standards  
> for
> implementation.

I don't see anyone denying this at all.

> The idea of separating service description from any technology for  
> service
> development originated from the concept of knowledge engineering in the
> domain of AI.

Not really. I mean, SOA like abstraction has been around for a while.

>  I cannot understand why people with AI background cannot see
> its root.

Even if we could, doesn't mean we'd agree that it was a good idea.

> Maybe I used an old book "Artificial Intelligence - A Modern
> Approach" published by Prentice Hall in 1995 ISBN # 0-13-103805-2. On  
> page
> 219,

I have it and like it. 3rd edition is v. nice.

>  it describes the difference between knowledge engineering and
> programming.

Yes, patronizing us really helps build good will. Can you try to absorb  
some of the push back? Understand it? Respond critically?

> Here it's the same analogy in semantic Web services. Service  
> description is
> a process of knowledge engineering while service development is a
> programming process while WSDL contains the coding details as the  
> result.

Not really. At least, I don't think so. There are different levels of  
abstraction we're dealing with.WSDL may, in some sense, be "closer to  
the metal", but it's pretty abstract.

>  I
> hope Dr. Parsia

I'm not a doctor.

> could calm down

That I am irate doesn't mean that I'm not on point. I don't see you  
responding at all to my reponses.

>  and see the difference and let us know if
> such an analogy is correct or not, and if such separation will enable  
> the
> service description document being implemented by multiple ways besides
> WSDL/SOAP.

And since you still conflate WSDL and SOAP I see little evidence that  
discussion is happening.

Cheers,
Bijan.
Received on Sunday, 27 November 2005 18:44:55 GMT

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