- From: Roger L. Costello <costello@mitre.org>
- Date: Fri, 04 Apr 2003 17:05:42 -0500
- To: Jim Farrugia <jim@spatial.maine.edu>
- CC: www-rdf-logic@w3.org
Thanks Jim! Domain knowledge is certainly helpful in making realistic examples! I will make the fixes you suggested. Thanks again. /Roger Jim Farrugia wrote: > > Roger, > > A few quick comments after (adimittedly only) skimming your example. > > 1. The aperture (last I knew) is determined by the lens, not > the camera, so if I'm right, it wouldn't make exact sense to say you are > seeking a _camera_ with aperture of at least 1.4. > > 2. An aperture (f-stop) of 1.2 does fall into the category of > "an aperture of at least 1.4" (at least in camera speak); yet > 1.2 is not at least 1.4 (in terms of numbers and the usual ordering > relation). This incongruity may cause some problems in understanding. > > 3. The aperture on all but the best zoom lenses is variable (e.g., 4.5-5.6), > so you may need the facility to compare the desired minimum value to a range > of values, not to just a single point value. > > 4. It's not clear to me from the way you state the query whether the > bounds on the shutter speed are to be taken as exact. That is, what > if you find a camera that has a minimum shutter speed of 1/8000 sec and a > maximum of 30 seconds (plus bulb?)? Would such a camera, assuming the other > requirements were met, satisfy your query? > > 5. Also, for the 300mm zoom lens, ... which lenses would work? Anything > that reaches to or covers 300mm (e.g., 75-300, 100-300, 100-400)? > > 6. I assume a 300mm fixed-focal-length, telephoto lens (i.e., not a zoom) > does not satsify the query? > > Oh, and if you find a 300mm/f1.4 lens please let me know where. :-) > > Jim > > On Fri, 4 Apr 2003, Roger L. Costello wrote: > > > > > Hi Folks, > > > > I am trying to create some simple examples which demonstrate the power > > of OWL. (I would like examples that are as compelling as Ian Davis' > > version of The Robber and the Speeder.) > > > > Below is my start at an example. It needs some work to make it > > "compelling". Can you help me flesh out this example to make it more > > compelling? > > > > Here's the example: > > > > BRIDGING THE TERMINOLOGY GAP USING OWL > > > > A key problem in achieving interoperability is to be able to recognize > > that two pieces of data are talking about the same thing. > > > > The following example shows how OWL may be used to bridge the > > "terminology gap". > > > > INTERESTED IN PURCHASING A CAMERA > > > > Query: "I am interested in purchasing a camera with an aperture of (at > > least) 1.4, a shutter speed that ranges from 1/2000 sec. to 10 sec., and > > with a 300mm zoom lens." > > > > This query can be expressed in XML as: > > > > <Camera> > > <aperture>1.4 (or better)</aperture> > > <shutter-speed>1/2000 sec. to 10 sec.</shutter-speed> > > <lens>300mm zoom</lens> > > </Camera> > > > > Thus, the query may be recast as: "Find all XML documents which overlap > > with the above XML document." > > > > IS THIS DOCUMENT RELEVANT? > > > > My Web Bot finds this document at a Web site: > > > > <PhotographyStore rdf:ID="Hunts" > > xmlns:rdf="&rdf;#"> > > <store-location>Malden, MA</store-location> > > <phone>617-555-1234</phone> > > <catalog rdf:parseType="Collection"> > > <SLR rdf:ID="Olympus-OM-10"> > > <f-stop>1.2</f-stop> > > <shutter-speed>1/2000 sec. to 10 sec.</shutter-speed> > > <compatible-lenses> > > <lens>35mm</lens> > > <lens>50mm</lens> > > <lens>300mm zoom</lens> > > </compatible-lenses> > > <cost>starting at: $325 USD</cost> > > </SLR> > > ... > > </catalog> > > </PhotographyStore> > > > > Is this document relevant? Does it meet the query specifications? > > > > To determine if there is a match, these questions must be answered: > > 1. What's the relationship between "SLR" and "Camera"? > > 2. What's the relationship between "f-stop" and "aperture"? > > > > RELATIONSHIP BETWEEN SLR AND CAMERA? > > > > This OWL rule (from the Camera Ontology) tells the Web Bot that an SLR > > is a type of Camera: > > > > <owl:Class rdf:ID="SLR"> > > <rdfs:subClassOf rdf:resource="#Camera"/> > > </owl:Class> > > > > RELATIONSHIP BETWEEN F-STOP AND APERTURE? > > > > This OWL rule tells the Web Bot that f-stop is equivalent to aperture: > > > > <owl:DatatypeProperty rdf:ID="f-stop"> > > <owl:equivalentProperty rdf:resource="#aperture"/> > > <rdfs:domain rdf:resource="#SLR"/> > > <rdfs:range rdf:resource="&xsd;#string"/> > > </owl:DatatypeProperty> > > > > My Web Bot now recognizes that the XML document it found at the Web site > > - is talking about Cameras, and > > - does show the aperture for the camera. > > > > Further, the aperture exceeds the minimum value specified by the query > > (1.4), and the shutter speed and lens criteria is met. > > > > Thus, my Web Bot has determined that this Olympus OM-10 SLR instance > > document is a match for my query! > > > > SUMMARY: INTEROPERABILITY DESPITE TERMINOLOGY DIFFERENCES! > > > > The example demonstrates how my Web Bot was able to utilize the data > > from the Web site, despite the fact that the XML document used different > > terminology. This interoperability was achieved through the use of the > > OWL Camera Ontology. > > > > ---- > > Okay, that's a start. Can you help to improve this example, i.e., show > > more OWL features, and make it more compelling? /Roger > > > >
Received on Friday, 4 April 2003 17:09:34 UTC