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Dear all:<br>
<br>
Please keep in mind that there are two different GoodRelations
properties that refer to quantities of items:<br>
<br>
a) gr:amountOfThisGood and<br>
b) gr:hasInventoryLevel<br>
<br>
gr:amountOfThisGood is attached to gr:TypeAndQuantity nodes and
indicates the quantity of the item included in the particular offer. In
80% of the cases, this should be 1.0 ("1.0"^^xsd.float), because the
price etc. is for one item. A value other than 1.0 is appropriate when
you sell a bundle of items or use units of measurement other than
"item/piece", e.g. selling <br>
<br>
"100 tiles"<br>
"500 g of butter", or<br>
"1 camera + 2 memory sticks"<br>
<br>
gr:hasInventoryLevel, on the contrary, can be used to indicate
inventory levels. While gr:amountOfThisGood is an owl:DatatypeProperty,
gr:hasInventoryLevel  is an owl:ObjectProperty with a range of
gr:QuantitativeValueFloat, because this allows for using arbitrary
units and also specifying ranges.<br>
<br>
It can only be attached to instances of
gr:ProductOrServicesSomeInstancesPlaceholder.<br>
<br>
So if you want to indicate inventory levels, use gr: hasInventoryLevel
in
combination with an instance of gr:QuantitativeValueFloat.<br>
<br>
<b>Example:</b> Assume you have 80 pieces of this controller card on
stock. Then, use the following pattern:<br>
<br>
<b><u>N3:</u></b><br>
<br>
foo:myProduct a gr:ProductOrServicesSomeInstancesPlaceholder;<br>
   rdfs:label "Personal SCSI 16-bit SCSI Controller"@en ;<br>
   gr:hasEAN_UCC-13 "00010363780"^^xsd:string ;<br>
   gr:hasManufacturer
<a class="moz-txt-link-rfc2396E" href="http://www.heppnetz.de/searchmonkey/product.html#heppcomputer"><http://www.heppnetz.de/searchmonkey/product.html#heppcomputer></a> ;<br>
   rdfs:comment "This low-cost, high-performance SCSI controller allows
you to connect up to seven professional mass-storage devices to your
computer."@en ;<br>
   rdfs:seeAlso
<a class="moz-txt-link-rfc2396E" href="http://www.heppnetz.de/searchmonkey/product.html"><http://www.heppnetz.de/searchmonkey/product.html></a>,
<a class="moz-txt-link-rfc2396E" href="http://www.heppnetz.de/searchmonkey/pscsi.jpg"><http://www.heppnetz.de/searchmonkey/pscsi.jpg></a> ;<br>
   foaf:depiction <a class="moz-txt-link-rfc2396E" href="http://www.heppnetz.de/searchmonkey/pscsi.jpg"><http://www.heppnetz.de/searchmonkey/pscsi.jpg></a>
;<br>
<b>   gr:hasInventoryLevel<br>
       [ a gr:QuantitativeValueFoat;<br>
         gr:hasValueFloat "80"^^xsd:float ;<br>
         gr:hasUnitOfMeasurement "C62"^^xsd:string<br>
       ] ;</b><br>
.<br>
<br>
RDFa:<br>
<br>
<div typeof="gr:ProductOrServicesSomeInstancesPlaceholder"
about="#myProduct"><br>
     Product Name:<br>
     <span property="rdfs:label">Personal SCSI 16-bit SCSI
Controller</span><br>
     <br/>Description:<br>
     <span property="rdfs:comment">This low-cost,
high-performance SCSI controller allows you to connect up to<br>
     seven professional mass-storage devices to your
computer.</span><br/><br>
     EAN/UPC code:<br>
     <span property="gr:hasEAN_UCC-13"
datatype="xsd:string">00010363780</span><br/><br>
     <span rel="rdfs:seeAlso media:image foaf:depiction"><br>
          <img src=<a class="moz-txt-link-rfc2396E" href="http://www.heppnetz.de/searchmonkey/pscsi.jpg">"http://www.heppnetz.de/searchmonkey/pscsi.jpg"</a>
alt="Product Image"/><br>
     </span><br>
<b>     <span rel="gr:hasInventoryLevel><br>
          <span typeof="gr:QuantitativeValueFoat> <br>
               <span property="gr:hasValueFloat"
datatype="xsd:float">80</span> items on stock.<br>
                <span property="hasUnitOfMeasurement"
datatype="xsd:string" content="C62"/><br>
          </span><br>
    </span></b>
<br>
</div><br>
<br>
<br>
Best<br>
<br>
Martin Hepp<br>
<pre class="moz-signature" cols="72">-- 
--------------------------------------------------------------
martin hepp
e-business & web science research group
universitaet der bundeswehr muenchen

e-mail:  <a class="moz-txt-link-abbreviated" href="mailto:mhepp@computer.org">mhepp@computer.org</a>
phone:   +49-(0)89-6004-4217
fax:     +49-(0)89-6004-4620
www:     <a class="moz-txt-link-freetext" href="http://www.unibw.de/ebusiness/">http://www.unibw.de/ebusiness/</a> (group)
         <a class="moz-txt-link-freetext" href="http://www.heppnetz.de/">http://www.heppnetz.de/</a> (personal)
skype:   mfhepp 
twitter: mfhepp

Check out GoodRelations for E-Commerce on the Web of Linked Data!
=================================================================

Webcast:
<a class="moz-txt-link-freetext" href="http://www.heppnetz.de/projects/goodrelations/webcast/">http://www.heppnetz.de/projects/goodrelations/webcast/</a>

Recipe for Yahoo SearcMonkey:
<a class="moz-txt-link-freetext" href="http://tr.im/rAbN">http://tr.im/rAbN</a>

Talk at the Semantic Technology Conference 2009: 
"Semantic Web-based E-Commerce: The GoodRelations Ontology"
<a class="moz-txt-link-freetext" href="http://tinyurl.com/semtech-hepp">http://tinyurl.com/semtech-hepp</a>

Overview article on Semantic Universe:
<a class="moz-txt-link-freetext" href="http://tinyurl.com/goodrelations-universe">http://tinyurl.com/goodrelations-universe</a>

Project page:
<a class="moz-txt-link-freetext" href="http://purl.org/goodrelations/">http://purl.org/goodrelations/</a>

Resources for developers:
<a class="moz-txt-link-freetext" href="http://www.ebusiness-unibw.org/wiki/GoodRelations">http://www.ebusiness-unibw.org/wiki/GoodRelations</a>

Tutorial materials:
CEC'09 2009 Tutorial: The Web of Data for E-Commerce: A Hands-on Introduction to the GoodRelations Ontology, RDFa, and Yahoo! SearchMonkey 
<a class="moz-txt-link-freetext" href="http://tr.im/grcec09">http://tr.im/grcec09</a>
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