ISSUE-499 ISSUE-449
authorLuc Moreau <l.moreau@ecs.soton.ac.uk>
Fri, 19 Oct 2012 15:40:16 +0100
changeset 4541 f85763972191
parent 4540 d005d76ab405
child 4542 7965e01a1bb3
ISSUE-499 ISSUE-449
model/diff.html
model/glossary.html
model/glossary.js
model/prov-dm.html
--- a/model/diff.html	Thu Oct 18 09:46:07 2012 -0600
+++ b/model/diff.html	Fri Oct 19 15:40:16 2012 +0100
@@ -1026,7 +1026,7 @@
 pre.sh_sourceCode .sh_attribute { color: #006400; }
 
 </style><link href="./extra-dm.css" rel="stylesheet" type="text/css" charset="utf-8"><link href="http://www.w3.org/StyleSheets/TR/W3C-ED" rel="stylesheet" type="text/css" charset="utf-8"></head> 
-  <body style="display: inherit; "><div class="head"><p><a href="http://www.w3.org/"><img width="72" height="48" src="http://www.w3.org/Icons/w3c_home" alt="W3C"></a></p><h1 class="title" id="title">PROV-DM: The PROV Data Model</h1><h2 id="subtitle"><a href="diff.html"><span class="insert">Changes</span></a><span class="insert"> since LC release</span></h2><h2 id="w3c-editor-s-draft-11-october-2012"><acronym title="World Wide Web Consortium">W3C</acronym> <span class="delete">Working</span><span class="insert">Editor's</span> Draft <span class="delete">24 July</span><span class="insert">11 October</span> 2012</h2><dl><dt>This version:</dt><dd><span class="delete">http://www.w3.org/TR/2012/WD-prov-dm-20120724/</span><a href="http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-dm.html"><span class="insert">http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-dm.html</span></a></dd><dt>Latest published version:</dt><dd><a href="http://www.w3.org/TR/prov-dm/">http://www.w3.org/TR/prov-dm/</a></dd><dt>Latest editor's draft:</dt><dd><a href="http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-dm.html">http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-dm.html</a></dd><dt>Previous version:</dt><dd><span class="delete">http://www.w3.org/TR/2012/WD-prov-dm-20120503/</span><span class="delete"> (</span><span class="delete">color-coded diffs</span><span class="delete">)</span><a href="http://www.w3.org/TR/2012/WD-prov-dm-20120724/"><span class="insert">http://www.w3.org/TR/2012/WD-prov-dm-20120724/</span></a></dd><dt>Editors:</dt><dd><a href="http://www.ecs.soton.ac.uk/~lavm/">Luc Moreau</a>, University of Southampton</dd>
+  <body style="display: inherit; "><div class="head"><p><a href="http://www.w3.org/"><img width="72" height="48" src="http://www.w3.org/Icons/w3c_home" alt="W3C"></a></p><h1 class="title" id="title">PROV-DM: The PROV Data Model</h1><h2 id="subtitle"><a href="diff.html"><span class="insert">Changes</span></a><span class="insert"> since LC release</span></h2><h2 id="w3c-editor-s-draft-19-october-2012"><acronym title="World Wide Web Consortium">W3C</acronym> <span class="delete">Working</span><span class="insert">Editor's</span> Draft <span class="delete">24 July</span><span class="insert">19 October</span> 2012</h2><dl><dt>This version:</dt><dd><span class="delete">http://www.w3.org/TR/2012/WD-prov-dm-20120724/</span><a href="http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-dm.html"><span class="insert">http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-dm.html</span></a></dd><dt>Latest published version:</dt><dd><a href="http://www.w3.org/TR/prov-dm/">http://www.w3.org/TR/prov-dm/</a></dd><dt>Latest editor's draft:</dt><dd><a href="http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-dm.html">http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-dm.html</a></dd><dt>Previous version:</dt><dd><span class="delete">http://www.w3.org/TR/2012/WD-prov-dm-20120503/</span><span class="delete"> (</span><span class="delete">color-coded diffs</span><span class="delete">)</span><a href="http://www.w3.org/TR/2012/WD-prov-dm-20120724/"><span class="insert">http://www.w3.org/TR/2012/WD-prov-dm-20120724/</span></a></dd><dt>Editors:</dt><dd><a href="http://www.ecs.soton.ac.uk/~lavm/">Luc Moreau</a>, University of Southampton</dd>
 <dd><a href="http://www.cs.ncl.ac.uk/people/Paolo.Missier">Paolo Missier</a>, Newcastle University</dd>
 <dt><span class="delete">Contributors:</span><span class="insert">Authors:</span></dt><dd><a href="http://semanticweb.org/wiki/Khalid_Belhajjame">Khalid Belhajjame</a>, University of Manchester</dd>
 <dd><span>Reza B'Far</span>, Oracle Corporation</dd>
@@ -1655,7 +1655,7 @@
 
 <p>To illustrate expanded relations, we consider the concept of
 association, described
-in <a class="section-ref" href="#section-agents-attribution-association-delegation"><span>Section 2.1.3</span></a>.  Agents may adopt <em>plans</em>, i.e.  sets of actions or steps, to achieve their
+in <a class="section-ref" href="#section-agents-attribution-association-delegation"><span>Section 2.1.3</span></a>.  Agents may <span class="delete">adopt</span><span class="insert">rely on</span> <em>plans</em>, i.e.  sets of actions or steps, to achieve their
 goals in the context of an activity.
 Hence, an expanded form of
 association relation allows for a plan to be specified. Plan is defined by subtyping and 
@@ -2299,6 +2299,9 @@
 
 <div class="glossary-ref">   <dfn id="concept-generation" class="internalDFN">Generation</dfn><sup><a class="internalDFN" href="#concept-generation"><span class="diamond"> ◊</span></a></sup> is the completion of production of a new entity by an activity. This entity did not exist before generation and becomes available for usage after this generation. </div>
 
+<p><span class="insert">Given that a generation is the completion of production of an entity, 
+it is instantaneous.</span></p>
+
 <p>
 </p><div class="attributes" id="attributes-generation"><dfn title="wasGeneratedBy" id="dfn-wasgeneratedby" class="internalDFN">Generation</dfn><sup><a class="internalDFN" href="#dfn-wasgeneratedby"><span class="diamond"> ◊</span></a></sup><span class="withPn">, written <span class="pnExpression">wasGeneratedBy(id; e, a, t, attrs)</span> in PROV-N,</span> has:
 <ul>
@@ -2346,6 +2349,11 @@
 <p><span class="glossary-ref">   <dfn id="concept-usage" class="internalDFN">Usage</dfn><sup><a class="internalDFN" href="#concept-usage"><span class="diamond"> ◊</span></a></sup> is the beginning of utilizing an entity by an activity. Before usage, the activity had not begun to utilize this entity and could not have been affected by the entity. </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>
 
 
+
+
+<p><span class="insert">Given that a usage  is  the beginning of utilizing an entity, it is 
+instantaneous.</span></p>
+
 <p></p><div class="attributes" id="attributes-usage"><dfn title="used" id="dfn-used" class="internalDFN">Usage</dfn><sup><a class="internalDFN" href="#dfn-used"><span class="diamond"> ◊</span></a></sup><span class="withPn">, written <span class="pnExpression">used(id; a, e, t, attrs)</span> in PROV-N,</span> has:
 <ul>
 <li><span class="attribute" id="usage.id">id</span>:  an <em class="rfc2119" title="optional">optional</em> identifier for a usage;</li> 
@@ -2420,6 +2428,11 @@
 <div class="glossary-ref">   <dfn id="concept-start" class="internalDFN">Start</dfn><sup><a class="internalDFN" href="#concept-start"><span class="diamond"> ◊</span></a></sup> is when an activity is deemed to have started.  The activity did not exist before its start. Any usage or generation involving an activity follows the activity's start. A start may refer to an entity, known as <dfn id="concept-start-trigger" class="internalDFN">trigger</dfn><sup><a class="internalDFN" href="#concept-start-trigger"><span class="diamond"> ◊</span></a></sup>, that set off the activity, or to an activity, known as <dfn id="concept-start-starter" class="internalDFN">starter</dfn><sup><a class="internalDFN" href="#concept-start-starter"><span class="diamond"> ◊</span></a></sup>, that generated the trigger. </div>
 
 
+
+
+<p><span class="insert">Given that a start is when an activity is deemed to have started, it 
+is instantaneous.</span></p>
+
 <p></p><div class="attributes" id="attributes-start">An activity <dfn title="wasStartedBy" id="dfn-wasstartedby" class="internalDFN">start</dfn><sup><a class="internalDFN" href="#dfn-wasstartedby"><span class="diamond"> ◊</span></a></sup><span class="withPn">, written <span class="pnExpression">wasStartedBy(id; a2, e, a1, t, attrs)</span> in PROV-N,</span> has:
 <ul>
 <li><span class="attribute" id="start.id">id</span>:  an <em class="rfc2119" title="optional">optional</em> identifier for the activity start;</li> 
@@ -2495,6 +2508,11 @@
 <div class="glossary-ref">   <dfn id="concept-end" class="internalDFN">End</dfn><sup><a class="internalDFN" href="#concept-end"><span class="diamond"> ◊</span></a></sup> is when an activity is deemed to have ended.  The activity no longer exists after its end. Any usage, generation, or invalidation involving an activity precedes the activity's end. An end may refer to an entity, known as <dfn id="concept-end-trigger" class="internalDFN">trigger</dfn><sup><a class="internalDFN" href="#concept-end-trigger"><span class="diamond"> ◊</span></a></sup>, that terminated the activity, or to an activity, known as <dfn id="concept-end-ender" class="internalDFN">ender</dfn><sup><a class="internalDFN" href="#concept-end-ender"><span class="diamond"> ◊</span></a></sup> that generated the trigger. </div>
 
 
+
+
+<p><span class="insert">Given that an end is when an activity is deemed to have ended, it is 
+instantaneous.</span></p>
+
 <p></p><div class="attributes" id="attributes-end">An activity <dfn title="wasEndedBy" id="dfn-wasendedby" class="internalDFN">end</dfn><sup><a class="internalDFN" href="#dfn-wasendedby"><span class="diamond"> ◊</span></a></sup><span class="withAsn">, written <span class="pnExpression">wasEndedBy(id; a2, e, a1, t, attrs)</span> in PROV-N,</span> has:
 <ul>
 <li><span class="attribute" id="end.id">id</span>:  an <em class="rfc2119" title="optional">optional</em> identifier for the activity end;</li> 
@@ -2527,6 +2545,11 @@
 
 
 
+
+
+<p><span class="insert">Given that an invalidation is the start  of destruction, cessation, or 
+expiry, it is instantaneous.</span></p>
+
 <p>
 Entities have a duration. Generation marks the beginning of an entity, whereas invalidation marks its end. 
 An entity's lifetime can end for different reasons:</p>
@@ -2956,7 +2979,7 @@
 <li><span class="attribute" id="association.id">id</span>:  an <em class="rfc2119" title="optional">optional</em> identifier for the association between an activity and an agent;</li> 
 <li><span class="attribute" id="association.activity">activity</span>: an identifier (<span class="name">a</span>) for the activity;</li>
 <li><span class="attribute" id="association.agent">agent</span>: an <em class="rfc2119" title="optional">optional</em> identifier (<span class="name">ag</span>) for the agent associated with the activity;</li>
-<li><span class="attribute" id="association.plan">plan</span>: an <em class="rfc2119" title="optional">optional</em> identifier (<span class="name">pl</span>) for the plan adopted by the agent in the context of this activity;
+<li><span class="attribute" id="association.plan">plan</span>: an <em class="rfc2119" title="optional">optional</em> identifier (<span class="name">pl</span>) for the plan<span class="delete"> adopted by </span>  the agent<span class="insert"> relied on</span> in the context of this activity;
 </li><li><span class="attribute" id="association.attributes">attributes</span>: an <em class="rfc2119" title="optional">optional</em> set (<span class="name">attrs</span>) of attribute-value pairs representing additional information about this association of this activity with this agent.</li>
 </ul></div>
 
@@ -3270,6 +3293,9 @@
 
 
 
+
+
+
 </div> 
 
 
@@ -3513,6 +3539,10 @@
 
 
 
+
+
+
+
 </div>
 
 <div id="component6" class="section"> 
@@ -3758,13 +3788,13 @@
 <div id="term-attribute-value" class="section">
 <h5><span class="secno">5.7.2.5 </span>prov:value</h5>
 
-<p><span class="glossary-ref">   The attribute <dfn id="concept-value-attribute" title="value-attribute" class="internalDFN"><span class="name">prov:value</span></dfn><sup><a class="internalDFN" href="#concept-value-attribute"><span class="diamond"> ◊</span></a></sup>  provides a <a href="#concept-value" class="internalDFN">Value</a> for an entity. </span></p>
+<p><span class="glossary-ref">   The attribute <dfn id="concept-value-attribute" title="value-attribute" class="internalDFN"><span class="name">prov:value</span></dfn><sup><a class="internalDFN" href="#concept-value-attribute"><span class="diamond"> ◊</span></a></sup>  provides a <span class="insert">value  that is a direct representation of an entity as a PROV-DM </span><a title="value" href="#concept-value" class="internalDFN">Value</a><span class="delete"> for an entity.</span><span class="insert">.</span> </span></p>
 
 
 
 <p>The attribute <span class="name">prov:value</span> is an <em class="rfc2119" title="optional">optional</em> attribute of entity.  The value associated with the  attribute <span class="name">prov:value</span> <em class="rfc2119" title="must">must</em> be a PROV-DM <a title="value" href="#concept-value" class="internalDFN">Value</a>. The attribute <span class="name">prov:value</span> <em class="rfc2119" title="may">may</em> occur at most once in a set of attribute-value pairs.</p>
 
-<div class="anexample" id="example_54"><div class="anexampleTitle">Example <span class="delete">53</span><span class="insert">54</span><sup><a class="internalDFN" href="#example_54"><span class="diamond"> ◊</span></a></sup></div>
+<div class="anexample" id="anexample-value1"><div class="anexampleTitle">Example <span class="delete">53</span><span class="insert">54</span><sup><a class="internalDFN" href="#anexample-value1"><span class="diamond"> ◊</span></a></sup></div>
 <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>.
 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.
 </p>
@@ -3777,6 +3807,26 @@
 </pre>
 </div>
 
+<p><span class="insert">
+Two different entities </span><em class="rfc2119" title="may"><span class="insert">may</span></em><span class="insert"> have the same value for the attribute 
+prov:value. For instance,
+when two entities, with the same prov:value, are generated by two 
+different activities, as illustrated
+by the following example.</span></p>
+
+<div class="anexample" id="anexample-value2"><div class="anexampleTitle"><span class="insert">Example 55</span><sup><a class="internalDFN" href="#anexample-value2"><span class="diamond"><span class="insert"> ◊</span></span></a></sup></div>
+<p><a href="#anexample-value1" class="anexample-ref"><span><span class="insert">Example 54</span></span></a><span class="insert"> illustrates an entity with a given value
+ </span><span class="name"><span class="insert">4</span></span><span class="insert">. This examples shows that another entity with the same value may be computed differently (by an addition).
+</span></p>
+<pre class="codeexample"><span class="insert">entity(ex:in1, [ prov:value=3 ]) 
+entity(ex:in2, [ prov:value=1 ]) 
+entity(ex:out2, [ prov:value=4 ])      // ex:out2 also has value 4
+activity(ex:add1, [ prov:type="addition" ])
+used(ex:add1, ex:in1)
+used(ex:add1, ex:in2)
+wasGeneratedBy(ex:out2, ex:add1)
+</span></pre>
+</div>
 
 
 </div>
@@ -3784,6 +3834,10 @@
 
 
 
+
+
+
+
 </div>
 
 <div id="term-value" class="section">
@@ -3826,7 +3880,7 @@
 
 
 
-<div class="anexample" id="anexample-value"><div class="anexampleTitle">Example <span class="delete">54</span><span class="insert">55</span><sup><a class="internalDFN" href="#anexample-value"><span class="diamond"> ◊</span></a></sup></div>
+<div class="anexample" id="anexample-value"><div class="anexampleTitle">Example <span class="delete">54</span><span class="insert">56</span><sup><a class="internalDFN" href="#anexample-value"><span class="diamond"> ◊</span></a></sup></div>
 <p>
 The following examples respectively are the string "abc", the integer number 1, and the IRI "http://example.org/foo".
 </p><pre class="codeexample">  "abc"
@@ -3848,7 +3902,7 @@
 <p>We note that PROV-DM <dfn title="time" id="dfn-time" class="internalDFN">time instants</dfn><sup><a class="internalDFN" href="#dfn-time"><span class="diamond"> ◊</span></a></sup> are defined according to xsd:dateTime [<cite><a class="bibref" rel="biblioentry" href="#bib-XMLSCHEMA11-2">XMLSCHEMA11-2</a></cite>].</p> 
 
 
-<div class="anexample" id="anexample-time"><div class="anexampleTitle">Example <span class="delete">55</span><span class="insert">56</span><sup><a class="internalDFN" href="#anexample-time"><span class="diamond"> ◊</span></a></sup></div>
+<div class="anexample" id="anexample-time"><div class="anexampleTitle">Example <span class="delete">55</span><span class="insert">57</span><sup><a class="internalDFN" href="#anexample-time"><span class="diamond"> ◊</span></a></sup></div>
 <p>
 In the following example, the generation time of entity <span class="name">e1</span> is expressed according to 
 <a href="http://www.w3.org/TR/xmlschema11-2/#dateTime">xsd:dateTime</a>  [<cite><a class="bibref" rel="biblioentry" href="#bib-XMLSCHEMA11-2">XMLSCHEMA11-2</a></cite>].</p>
@@ -3912,7 +3966,7 @@
 <li>Sub-types and sub-relations can be expressed by means of the reserved attribute 
 <a href="#term-attribute-type"><span class="name">prov:type</span></a>.
 
-<div class="anexample" id="anexample-sub-relation"><div class="anexampleTitle">Example <span class="delete">56</span><span class="insert">57</span><sup><a class="internalDFN" href="#anexample-sub-relation"><span class="diamond"> ◊</span></a></sup></div>
+<div class="anexample" id="anexample-sub-relation"><div class="anexampleTitle">Example <span class="delete">56</span><span class="insert">58</span><sup><a class="internalDFN" href="#anexample-sub-relation"><span class="diamond"> ◊</span></a></sup></div>
 <p>
 In the following example,  <span class="name">e2</span> is a translation of <span class="name">e1</span>,
 expressed as a sub-type of derivation.
@@ -3921,7 +3975,7 @@
 </pre>
 </div>
 
-<div class="anexample" id="anexample-sub-type"><div class="anexampleTitle">Example <span class="delete">57</span><span class="insert">58</span><sup><a class="internalDFN" href="#anexample-sub-type"><span class="diamond"> ◊</span></a></sup></div>
+<div class="anexample" id="anexample-sub-type"><div class="anexampleTitle">Example <span class="delete">57</span><span class="insert">59</span><sup><a class="internalDFN" href="#anexample-sub-type"><span class="diamond"> ◊</span></a></sup></div>
 <p>
 In the following example,  <span class="name">e</span> is described as a Car, a type of entity.
 </p><pre class="codeexample"> 
@@ -3937,7 +3991,7 @@
 <li>Application and domain specific roles can be expressed by means of the reserved attribute 
 <a href="#term-attribute-role"><span class="name">prov:role</span></a>.
 
-<div class="anexample" id="anexample-usage-with-role"><div class="anexampleTitle">Example <span class="delete">58</span><span class="insert">59</span><sup><a class="internalDFN" href="#anexample-usage-with-role"><span class="diamond"> ◊</span></a></sup></div>
+<div class="anexample" id="anexample-usage-with-role"><div class="anexampleTitle">Example <span class="delete">58</span><span class="insert">60</span><sup><a class="internalDFN" href="#anexample-usage-with-role"><span class="diamond"> ◊</span></a></sup></div>
 <p>
 In the following example,  two computers  <span class="name">ex:laptop4</span> and <span class="name">ex:desktop9</span> are used in different roles in a work activity.
 </p><pre class="codeexample"> 
@@ -4241,6 +4295,9 @@
 
 </span></li><li> <a href="http://www.w3.org/2011/prov/track/issues/519"><span class="insert">ISSUE-519</span></a><span class="insert">, </span><a href="http://www.w3.org/2011/prov/track/issues/523"><span class="insert">ISSUE-523</span></a><span class="insert">, </span><a href="http://www.w3.org/2011/prov/track/issues/524"><span class="insert">ISSUE-524</span></a><span class="insert">, </span><a href="http://www.w3.org/2011/prov/track/issues/529"><span class="insert">ISSUE-529</span></a><span class="insert">: 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.
 </span></li><li> <a href="http://www.w3.org/2011/prov/track/issues/495"><span class="insert">ISSUE-495</span></a><span class="insert">: made explicit which section, figure, table was informative or normative.
+</span></li><li> <a href="http://www.w3.org/2011/prov/track/issues/521"><span class="insert">ISSUE-521</span></a><span class="insert">: now states that "an agent relied on a plan" instead of "an agent adopted a plan".
+</span></li><li> <a href="http://www.w3.org/2011/prov/track/issues/499"><span class="insert">ISSUE-499</span></a><span class="insert">: Made explicit that generation/usage/invalidation/start/end are implicit.
+</span></li><li> <a href="http://www.w3.org/2011/prov/track/issues/449"><span class="insert">ISSUE-449</span></a><span class="insert">: Clarified definition of prov:value attribute and added an example.
 </span></li></ul>
 
 </div>
--- a/model/glossary.html	Thu Oct 18 09:46:07 2012 -0600
+++ b/model/glossary.html	Fri Oct 19 15:40:16 2012 +0100
@@ -273,7 +273,7 @@
 
 
 <span class="glossary" id="glossary-value-attribute">  
-The attribute <dfn id="concept-value-attribute" title="value-attribute"><span class="name">prov:value</span></dfn>  provides a <a>Value</a> for an entity.
+The attribute <dfn id="concept-value-attribute" title="value-attribute"><span class="name">prov:value</span></dfn>  provides a value  that is a direct representation of an entity as a PROV-DM <a title="value">Value</a>.
 </span>
 
 <span class="glossary" id="glossary-provenance-service">  
--- a/model/glossary.js	Thu Oct 18 09:46:07 2012 -0600
+++ b/model/glossary.js	Fri Oct 19 15:40:16 2012 +0100
@@ -3,7 +3,7 @@
 //  with <script src="glossary.js" class="remove"></script>
 //Insert glossary definitions with the following 
 // <div class="glossary-ref" ref="glossary-generation"></div>
-glossary_hg='http://dvcs.w3.org/hg/prov/file/90c3e84c18cd/model/glossary.html';
+glossary_hg='http://dvcs.w3.org/hg/prov/file/d005d76ab405/model/glossary.html';
 glossary_string= 
 ' ' + 
 '<html> ' + 
@@ -280,7 +280,7 @@
 ' ' + 
 ' ' + 
 '<span class="glossary" id="glossary-value-attribute">   ' + 
-'The attribute <dfn id="concept-value-attribute" title="value-attribute"><span class="name">prov:value</span></dfn>  provides a <a>Value</a> for an entity. ' + 
+'The attribute <dfn id="concept-value-attribute" title="value-attribute"><span class="name">prov:value</span></dfn>  provides a value  that is a direct representation of an entity as a PROV-DM <a title="value">Value</a>. ' + 
 '</span> ' + 
 ' ' + 
 '<span class="glossary" id="glossary-provenance-service">   ' + 
--- a/model/prov-dm.html	Thu Oct 18 09:46:07 2012 -0600
+++ b/model/prov-dm.html	Fri Oct 19 15:40:16 2012 +0100
@@ -1780,6 +1780,9 @@
 
 <div class="glossary-ref" data-ref="glossary-generation"></div>
 
+<p>Given that a generation is the completion of production of an entity, 
+it is instantaneous.</p>
+
 <p>
 <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:
 <ul>
@@ -1829,6 +1832,8 @@
 
 <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>
 
+<p>Given that a usage  is  the beginning of utilizing an entity, it is 
+instantaneous.</p>
 
 <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:
 <ul>
@@ -1907,6 +1912,8 @@
 
 <div class="glossary-ref" data-ref="glossary-start"></div>
 
+<p>Given that a start is when an activity is deemed to have started, it 
+is instantaneous.</p>
 
 <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:
 <ul>
@@ -1988,6 +1995,8 @@
 
 <div class="glossary-ref" data-ref="glossary-end"></div>
 
+<p>Given that an end is when an activity is deemed to have ended, it is 
+instantaneous.</p>
 
 <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:
 <ul>
@@ -2020,7 +2029,8 @@
 
 <div class="glossary-ref" data-ref="glossary-invalidation"></div>
 
-
+<p>Given that an invalidation is the start  of destruction, cessation, or 
+expiry, it is instantaneous.</p>
 
 <p>
 Entities have a duration. Generation marks the beginning of an entity, whereas invalidation marks its end. 
@@ -3292,7 +3302,7 @@
 
 <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>
 
-<div class="anexample">
+<div class="anexample" id="anexample-value1">
 <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>.
 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.
 </p>
@@ -3306,6 +3316,28 @@
 </pre>
 </div>
 
+<p>
+Two different entities MAY have the same value for the attribute 
+prov:value. For instance,
+when two entities, with the same prov:value, are generated by two 
+different activities, as illustrated
+by the following example.</p>
+
+<div class="anexample" id="anexample-value2">
+<p><a href="#anexample-value1" class="anexample-ref"><span>Example REF</span></a> illustrates an entity with a given value
+ <span class="name">4</span>. This examples shows that another entity with the same value may be computed differently (by an addition).
+</p>
+<pre class="codeexample">
+entity(ex:in1, [ prov:value=3 ]) 
+entity(ex:in2, [ prov:value=1 ]) 
+entity(ex:out2, [ prov:value=4 ])      // ex:out2 also has value 4
+activity(ex:add1, [ prov:type="addition" ])
+used(ex:add1, ex:in1)
+used(ex:add1, ex:in2)
+wasGeneratedBy(ex:out2, ex:add1)
+</pre>
+</div>
+
 
 </section>
 
@@ -3851,6 +3883,8 @@
 <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.
 <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.
 <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".
+<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.
+<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.
 </ul>
 
 </section>