--- a/model/prov-dm-constraints.html Mon Apr 02 16:37:33 2012 +0100
+++ b/model/prov-dm-constraints.html Mon Apr 02 16:53:16 2012 +0100
@@ -300,7 +300,7 @@
<section id='prov-dm-refinement'>
<h2>Data Model Refinement</h2>
-<p>Underpinning the PROV-DM data model is a notion of event, marking transitions in the world (when entities are generated, used, or invalidated, or activities started or ended). This notion of event is not first-class in the data model, but underpins many of its concepts and its semantics [[PROV-SEM]]. Thus, using this notion of event, we can provide an interpretation for the data model, which in turn can allow creators of provenance assertions to make their assertions more robust. </p>
+<p>Underpinning the PROV-DM data model is a notion of event, marking transitions in the world (when entities are generated, used, or invalidated, or activities started or ended). This notion of event is not first-class in the data model, but underpins many of its concepts and its semantics [[PROV-SEM]]. Thus, using this notion of event, we can provide an interpretation for the data model, which in turn can allow creators of provenance descriptons to make their descriptions more robust. </p>
<section id='section-time-event'>
@@ -1276,7 +1276,7 @@
<div class='interpretation' id='usage-within-activity'>Given an activity with identifier <span class="name">a</span>, an entity with identifier <span class="name">e</span>, a set
of attribute-value pairs <span class="name">attrs</span>, and optional time <span class="name">t</span>, <span class='conditional'>if</span>
- assertion <span class="name">used(a,e,attrs)</span> or <span class="name">used(a,e,attrs,t)</span> holds, <span class='conditional'>then</span> the following ordering constraint holds:
+ <span class="name">used(a,e,attrs)</span> or <span class="name">used(a,e,attrs,t)</span> holds, <span class='conditional'>then</span> the following ordering constraint holds:
the <a title="entity usage event">usage</a> of the entity denoted by <span class="name">e</span> <a>precedes</a> the <a title="activity end event">end</a> of
activity denoted by <span class="name">a</span> and <a>follows</a> its <a title="activity start event">start</a>.
</div>
@@ -1489,12 +1489,12 @@
<div class="anexample">
<p>
-In the following assertions, a workflow execution <span class="name">a0</span> consists of two sub-workflow executions <span class="name">a1</span> and <span class="name">a2</span>.
+In the following descriptions, a workflow execution <span class="name">a0</span> consists of two sub-workflow executions <span class="name">a1</span> and <span class="name">a2</span>.
Sub-workflow execution <span class="name">a2</span> generates entity <span class="name">e</span>, so does <span class="name">a0</span>.</p>
<pre class="codeexample">
-activity(a0,,,[prov:type="workflow execution"])
-activity(a1,,,[prov:type="workflow execution"])
-activity(a2,,,[prov:type="workflow execution"])
+activity(a0, [prov:type="workflow execution"])
+activity(a1, [prov:type="workflow execution"])
+activity(a2, [prov:type="workflow execution"])
wasInformedBy(a2,a1)
wasGeneratedBy(e,a0)
@@ -1514,20 +1514,20 @@
<div class="anexample">
<p>
-The same example is now revisited, with the following assertions that are structurally well-formed. Two accounts are introduced, and there is a single generation for entity <span
+The same example is now revisited, with the following descriptions that are structurally well-formed. Two accounts are introduced, and there is a single generation for entity <span
class="name">e</span> per account.</p>
<p>In a first account, entitled "summary", we find:</p>
<pre class="codeexample">
- activity(a0,t1,t2,[prov:type="workflow execution"])
- wasGeneratedBy(e,a0)
+activity(a0,t1,t2,[prov:type="workflow execution"])
+wasGeneratedBy(e,a0,-)
</pre>
<p>In a second account, entitled "detail", we find:</p>
<pre class="codeexample">
- activity(a1,t1,t3,[prov:type="workflow execution"])
- activity(a2,t3,t2,[prov:type="workflow execution"])
- wasInformedBy(a2,a1)
- wasGeneratedBy(e,a2)
+activity(a1,t1,t3,[prov:type="workflow execution"])
+activity(a2,t3,t2,[prov:type="workflow execution"])
+wasInformedBy(a2,a1)
+wasGeneratedBy(e,a2,-)
</pre>
</div>
@@ -1555,8 +1555,8 @@
<div class='inference' id='derivation-use'>
<p>Given an activity <span class="name">a</span>, entities denoted by <span class="name">e1</span> and <span class="name">e2</span>, and sets of attribute-value
pairs <span class="name">dAttrs</span>, <span class="name">gAttrs</span>,
-<span class='conditional'>if</span> <span class="name">wasDerivedFrom(e2,e1, a, dAttrs)</span> and <span class="name">wasGeneratedBy(e2,a,gAttrs)</span> hold, <span
-class='conditional'>then</span> <span class="name">used(a,e1,uAttrs)</span> also holds
+<span class='conditional'>if</span> <span class="name">wasDerivedFrom(e2,e1, a, dAttrs)</span> and <span class="name">wasGeneratedBy(e2,a,-,gAttrs)</span> hold, <span
+class='conditional'>then</span> <span class="name">used(a,e1,-,uAttrs)</span> also holds
for some set of attribute-value pairs <span class="name">uAttrs</span>.
</div>
<p>This inference is justified by the fact that the entity denoted by <span class="name">e2</span> is generated by at most one activity in a given account
@@ -1565,13 +1565,13 @@
<p>We note that the converse inference, does not hold.
-From <span class="name">wasDerivedFrom(e2,e1)</span> and <span class="name">used(a,e1)</span>, one cannot
-derive <span class="name">wasGeneratedBy(e2,a,attrs2)</span> because identifier <span class="name">e1</span> may occur in usages performed by many activities, which may have not generated the entity denoted by <span class="name">e2</span>.</p>
+From <span class="name">wasDerivedFrom(e2,e1)</span> and <span class="name">used(a,e1,-)</span>, one cannot
+derive <span class="name">wasGeneratedBy(e2,a,-)</span> because identifier <span class="name">e1</span> may occur in usages performed by many activities, which may have not generated the entity denoted by <span class="name">e2</span>.</p>
<p>
An account is said to be structurally well-formed if
-it satisfies the constraint <a href="#generation-uniqueness">generation-uniqueness</a>. If an account is structurally well-formed, it support the inference <a
+it satisfies the constraint <a href="#generation-uniqueness">generation-uniqueness</a>. If an account is structurally well-formed, it supports the inference <a
href="#derivation-use">derivation-use</a>.</p>
<p> Taking the union of two accounts is another account,
@@ -1608,6 +1608,7 @@
</div>
-->
+<!--
<div class="note">
Can the semantics characterize better what can be achieved with structurally well-formed accounts?
</div>
@@ -1626,6 +1627,8 @@
consider an abbreviation for this: wasGeneratedBy*(ex:s_3,ex:a2).</p>
</div>
+-->
+
</section>