--- a/model/ProvenanceModel.html Wed Sep 07 09:22:35 2011 +0100
+++ b/model/ProvenanceModel.html Wed Sep 07 09:50:24 2011 +0100
@@ -746,6 +746,8 @@
<p>In PIDM, a <dfn id="dfn-Use">use expression</dfn> is a representation of a world event: the consumption of a characterized thing by an activity. The representation includes a description of the function of this thing with respect to the activity.</p>
+<p>In the Provenance Abstract Syntax Notation, a use expression's text matches the <span class='nonterminal'>use</span> production of the grammar defined in this specification document.</p>
+
<div class='grammar'>
<span class="nonterminal">use</span> :=
<span class="name">used</span>
@@ -824,26 +826,69 @@
<li> transitive nature of derivation.
</ul></div>
-<p><dfn id="dfn-Derivation">Derivation</dfn> expresses that some characterized thing is transformed from, created from, or affected by another characterized thing. </p>
+<p>In PIDM, a <dfn id="dfn-Derivation">derivation expression</dfn> is a representation that some characterized thing is transformed from, created from, or affected by another characterized thing in the world. </p>
-<p>PIL offers two different kinds of assertions by which asserters can formulate derivations. The first one is tightly connected to the notion of process execution, whereas the second one is not. The first kind of assertion is particularly suitable for asserters who have an intimate knowledge of process executions, and offers a more precise description of derivation, whereas the second does not put such a requirement on the asserter, and allows a less precise description of derivation to be asserted. From these assertions, further derivations can be inferred by transitive closure. </p>
+<p>PIDM offers two different kinds of expressions by which asserters can formulate derivations. The first one is tightly connected to the notion of process execution, whereas the second one is not. The first kind of assertion is particularly suitable for asserters who have an intimate knowledge of process executions, is more prescriptive, but offers a more precise description of derivation, whereas the second does not put such a requirement on the asserter, and allows a less precise description of derivation to be formulated. Both expressions need to be asserted by asserters, since PIDM does not provide the means to infer them; however, from these assertions, further derivations can be inferred by transitive closure. </p>
+
+<p>In the Provenance Abstract Syntax Notation, a derivation expression's text matches the <span class='nonterminal'>derivation</span> production of the grammar defined in this specification document.</p>
+
+
+<div class='grammar'>
+<span class="nonterminal">derivation</span> :=
+<span class="nonterminal">pe-linked-derivation</span>
+| <span class="nonterminal">pe-independent-derivation</span>
+| <span class="nonterminal">transitive-derivation</span><br/>
+
+<span class="nonterminal">pe-linked-derivation</span>:=
+<span class="name">wasDerivedFrom</span>
+<span class="name">(</span>
+<span class="nonterminal">identifier</span>
+<span class="name">,</span>
+<span class="nonterminal">identifier</span>
+[<span class="name">,</span>
+<span class="nonterminal">processExecution</span>
+<span class="name">,</span>
+<span class="nonterminal">role</span>
+<span class="name">,</span>
+<span class="nonterminal">role</span>]
+<span class="name">)</span><br/>
+
+<span class="nonterminal">pe-independent-derivation</span>:=
+<span class="name">wasEventuallyDerivedFrom</span>
+<span class="name">(</span>
+<span class="nonterminal">identifier</span>
+<span class="name">,</span>
+<span class="nonterminal">identifier</span>
+<span class="name">)</span><br/>
+
+<span class="nonterminal">transitivederivation</span>:=
+<span class="name">dependedOn</span>
+<span class="name">(</span>
+<span class="nonterminal">identifier</span>
+<span class="name">,</span>
+<span class="nonterminal">identifier</span>
+<span class="name">)</span><br/>
+</div>
+
+<p>The three kinds of derivations are successively introduced.</p>
+
<section>
<h4>Process Execution Linked Derivation Assertion</h4>
-<p>A process execution linked derivation, which, by definition of derivation, expresses that some characterized thing is transformed from, created from, or affected by another characterized thing, entails a process execution that transforms, creates or affects this characterized thing.</pe>
+<p>A process execution linked derivation expression, which, by definition of derivation, is a representation that some characterized thing is transformed from, created from, or affected by another characterized thing, also entails the existence of a process execution that represents an activity that transforms, creates or affects this characterized thing.</pe>
-<p>In its full form, a process-execution linked derivation assertion, noted <span class="name">wasDerivedFrom(e2,e1,pe,r2,r1)</span>:
+<p>In its full form, a process-execution linked derivation expression, noted <span class="name">wasDerivedFrom(e2,e1,pe,r2,r1)</span> in the Provenance Abstract Syntax Notation:
<ul>
-<li> refers to an entity <span class="name">e2</span>, denoting the used characterized thing;
-<li> refers to an entity <span class="name">e1</span>, denoting the generated characterized thing;
-<li> refers to process execution <span class="name">pe</span>;
-<li> contains a role <span class="name">r2</span>.
-<li> contains a role <span class="name">r1</span>.
+<li> refers to an entity identified by <span class="name">e2</span>, which is a representation of the used characterized thing;
+<li> refers to an entity identified by <span class="name">e1</span>, which is a representation of the generated characterized thing;
+<li> refers to a process execution identified by <span class="name">pe</span>, which is a representation of the activity using and generating the above characterized things;
+<li> contains a role <span class="name">r2</span>, which is the function of <span class="name">e2</span> during its generation by <span class="name">pe</span> .
+<li> contains a role <span class="name">r1</span>, which is the function of <span class="name">e1</span> during its use by <span class="name">pe</span>.
</ul>
-This assertion expresses that the process execution <span class="name">pe</span>, by
-using the thing denoted by <span class="name">e1</span> with role <span class="name">r1</span> derived the
-thing denoted by entity <span class="name">e2</span> and generated it with
+This assertion expresses that the activity represented by process execution <span class="name">pe</span>, by
+using the thing represented by <span class="name">e1</span> with role <span class="name">r1</span> derived the
+thing represented by entity <span class="name">e2</span> and generated it with
role <span class="name">r2</span>.
</p>