model/prov-dm.html
changeset 4541 f85763972191
parent 4533 434fcd9c8a2b
child 4542 7965e01a1bb3
     1.1 --- a/model/prov-dm.html	Thu Oct 18 09:46:07 2012 -0600
     1.2 +++ b/model/prov-dm.html	Fri Oct 19 15:40:16 2012 +0100
     1.3 @@ -1780,6 +1780,9 @@
     1.4  
     1.5  <div class="glossary-ref" data-ref="glossary-generation"></div>
     1.6  
     1.7 +<p>Given that a generation is the completion of production of an entity, 
     1.8 +it is instantaneous.</p>
     1.9 +
    1.10  <p>
    1.11  <div class="attributes" id="attributes-generation"><dfn title="wasGeneratedBy">Generation</dfn><span class="withPn">, written <span class="pnExpression">wasGeneratedBy(id; e, a, t, attrs)</span> in PROV-N,</span> has:
    1.12  <ul>
    1.13 @@ -1829,6 +1832,8 @@
    1.14  
    1.15  <p><span class="glossary-ref" data-ref="glossary-usage"></span>  (Note: This definition is formulated for a given usage; it is permitted for an activity to have used a same entity multiple times.)</p>
    1.16  
    1.17 +<p>Given that a usage  is  the beginning of utilizing an entity, it is 
    1.18 +instantaneous.</p>
    1.19  
    1.20  <p><div class="attributes" id="attributes-usage"><dfn title="used">Usage</dfn><span class="withPn">, written <span class="pnExpression">used(id; a, e, t, attrs)</span> in PROV-N,</span> has:
    1.21  <ul>
    1.22 @@ -1907,6 +1912,8 @@
    1.23  
    1.24  <div class="glossary-ref" data-ref="glossary-start"></div>
    1.25  
    1.26 +<p>Given that a start is when an activity is deemed to have started, it 
    1.27 +is instantaneous.</p>
    1.28  
    1.29  <p><div class="attributes" id="attributes-start">An activity <dfn title="wasStartedBy">start</dfn><span class="withPn">, written <span class="pnExpression">wasStartedBy(id; a2, e, a1, t, attrs)</span> in PROV-N,</span> has:
    1.30  <ul>
    1.31 @@ -1988,6 +1995,8 @@
    1.32  
    1.33  <div class="glossary-ref" data-ref="glossary-end"></div>
    1.34  
    1.35 +<p>Given that an end is when an activity is deemed to have ended, it is 
    1.36 +instantaneous.</p>
    1.37  
    1.38  <p><div class="attributes" id="attributes-end">An activity <dfn title="wasEndedBy">end</dfn><span class="withAsn">, written <span class="pnExpression">wasEndedBy(id; a2, e, a1, t, attrs)</span> in PROV-N,</span> has:
    1.39  <ul>
    1.40 @@ -2020,7 +2029,8 @@
    1.41  
    1.42  <div class="glossary-ref" data-ref="glossary-invalidation"></div>
    1.43  
    1.44 -
    1.45 +<p>Given that an invalidation is the start  of destruction, cessation, or 
    1.46 +expiry, it is instantaneous.</p>
    1.47  
    1.48  <p>
    1.49  Entities have a duration. Generation marks the beginning of an entity, whereas invalidation marks its end. 
    1.50 @@ -3292,7 +3302,7 @@
    1.51  
    1.52  <p>The attribute <span class="name">prov:value</span> is an OPTIONAL attribute of entity.  The value associated with the  attribute <span class="name">prov:value</span> MUST be a PROV-DM <a title="value">Value</a>. The attribute <span class="name">prov:value</span> MAY occur at most once in a set of attribute-value pairs.</p>
    1.53  
    1.54 -<div class="anexample">
    1.55 +<div class="anexample" id="anexample-value1">
    1.56  <p>The following example illustrates the provenance of the number <span class="name">4</span> obtained by an activity that computed the length of an input string <span class="name">"abcd"</span>.
    1.57  The input and the output are expressed as entities <span class="name">ex:in</span> and <span class="name">ex:out</span>, respectively. They each have a <span class="name">prov:value</span> attribute associated with the corresponding value.
    1.58  </p>
    1.59 @@ -3306,6 +3316,28 @@
    1.60  </pre>
    1.61  </div>
    1.62  
    1.63 +<p>
    1.64 +Two different entities MAY have the same value for the attribute 
    1.65 +prov:value. For instance,
    1.66 +when two entities, with the same prov:value, are generated by two 
    1.67 +different activities, as illustrated
    1.68 +by the following example.</p>
    1.69 +
    1.70 +<div class="anexample" id="anexample-value2">
    1.71 +<p><a href="#anexample-value1" class="anexample-ref"><span>Example REF</span></a> illustrates an entity with a given value
    1.72 + <span class="name">4</span>. This examples shows that another entity with the same value may be computed differently (by an addition).
    1.73 +</p>
    1.74 +<pre class="codeexample">
    1.75 +entity(ex:in1, [ prov:value=3 ]) 
    1.76 +entity(ex:in2, [ prov:value=1 ]) 
    1.77 +entity(ex:out2, [ prov:value=4 ])      // ex:out2 also has value 4
    1.78 +activity(ex:add1, [ prov:type="addition" ])
    1.79 +used(ex:add1, ex:in1)
    1.80 +used(ex:add1, ex:in2)
    1.81 +wasGeneratedBy(ex:out2, ex:add1)
    1.82 +</pre>
    1.83 +</div>
    1.84 +
    1.85  
    1.86  </section>
    1.87  
    1.88 @@ -3851,6 +3883,8 @@
    1.89  <li> <a href="http://www.w3.org/2011/prov/track/issues/519">ISSUE-519</a>, <a href="http://www.w3.org/2011/prov/track/issues/523">ISSUE-523</a>, <a href="http://www.w3.org/2011/prov/track/issues/524">ISSUE-524</a>, <a href="http://www.w3.org/2011/prov/track/issues/529">ISSUE-529</a>: changed UML diagram of figure 8 by removing explicit inheritance from influence for  usage, start, end, generation, invalidation, communication, derivation, attribution, association, and delegation.  Instead, introduced correspondance table 7.  Furthermore, in response to these issues, it was made clear that PROV defines no attribute specific to subtypes such as SoftwareAgent, ..., Plan, Revision, Bundle, Collection.
    1.90  <li> <a href="http://www.w3.org/2011/prov/track/issues/495">ISSUE-495</a>: made explicit which section, figure, table was informative or normative.
    1.91  <li> <a href="http://www.w3.org/2011/prov/track/issues/521">ISSUE-521</a>: now states that "an agent relied on a plan" instead of "an agent adopted a plan".
    1.92 +<li> <a href="http://www.w3.org/2011/prov/track/issues/499">ISSUE-499</a>: Made explicit that generation/usage/invalidation/start/end are implicit.
    1.93 +<li> <a href="http://www.w3.org/2011/prov/track/issues/449">ISSUE-449</a>: Clarified definition of prov:value attribute and added an example.
    1.94  </ul>
    1.95  
    1.96  </section>