[Top] [All Lists]

[ontolog-forum] Composition vs. Aggregation (WAS: An Ontology Modeling D

To: "[ontolog-forum]" <ontolog-forum@xxxxxxxxxxxxxxxx>
From: Duane Nickull <dnickull@xxxxxxxxx>
Date: Thu, 26 Mar 2009 09:55:29 -0700
Message-id: <C5F10191.3F33%dnickull@xxxxxxxxx>
This is also precisely why I consider “Composite Applications” to be an anti-pattern of SOA.


Glad that I am not the only UML head in this crowd.


On 3/26/09 8:09 AM, "Schiffel, Jeffrey A" <jeffrey.a.schiffel@xxxxxxxxxx> wrote:

UML has two composition associations. In the aggregation, the parts exist whether the whole exists or not. A football team still exists even after the game is over, when all the players have gone home. In the compostion, the parts vanish. This enables constructors and destructors in software code, for example.

This sort of discussion came up in the conceptual graphs list a while ago, during postings regarding the wholeness of a watch when a spring was replace (still same watch), and when a body of water was separated into two parts.


-- Jeff Schiffel

From: Duane Nickull [mailto:dnickull@xxxxxxxxx]
Does “part” imply a UML 2.0 composite binary relationship? What the relationship between mother and offspring is is different.  Composite implies that the part is “part of” the whole and when the timeline for the whole ends, the timeline for the parts also ends.  As Cecil correctly noted, there are obvious exceptions to this.

The special dependency for this type of relationship is that the offspring is in a special “made from” relationship to two parents.  Once certain events are past, the dependency (or some of it) disappears to the point where most offspring outlive their parents.  For example, after the father’s sperm is contributed, there is no real need for the father other than support (obviously I am being very un-emotional here so no flames please).  As soon as the fetus is of a certain age, the dependency upon the mother is also somewhat reduced as medical professionals and society can help the child survive outside the womb.  Again, this is totally not considering the emotional requirements, only basic survival.  Obviously a child probably fares better with two living parents devoted to the child’s wellbeing.

Interesting discussion however.


On 3/25/09 4:34 PM, "Richard H. McCullough" <rhm@xxxxxxxxxxxxx> wrote:

Cecil (and Chris)

I would paraphrase your  concerns differently:
The standard definition of "part" is not  appropriate.
The parasite is a kind of  "foreign part", not a  "natural
part" of an organism.   A different term should be  used
in this context.

So you could blame me for mis-using  "part".
Or you could blame a particular ontology.
Don't blame  epistemology.

ditto for fetus.


> Well, I have run  into this issue before (trying to use Dolce as a top
> level for  parasitic infections where they go through life forms)and I
> would  simply say that this view is exactly why epistemology has no place
> in   real world (at least health care) ontologies.
>  Cecil
> Richard H. McCullough wrote:
>> From the  viewpoint of metaphysics/epistemology,
>> a fetus is not a human  being, it is a part of a human being
>> (the mother). After birth, it  is a human being (the newborn).
>>      *From:* Azamat <mailto:abdoul@xxxxxxxxxxxxxx>

>>      development. That means abortion, in a sense, is a  sort
>>     of killing of a human being by a  human being.

Message  Archives: http://ontolog.cim3.net/forum/ontolog-forum/  
Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/  
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared  Files: http://ontolog.cim3.net/file/
Community  Wiki: http://ontolog.cim3.net/wiki/
To  join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J
To  Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx

Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/  
Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/  
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/ 
To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J
To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx    (01)

<Prev in Thread] Current Thread [Next in Thread>