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Re: OWL class restriction

From: Uli Sattler <sattler@cs.man.ac.uk>
Date: Thu, 14 Jan 2010 12:30:10 +0000
Cc: Rinke Hoekstra <hoekstra@uva.nl>, Alessandro Maccagnan <maccagnan@math.unipd.it>, public-owl-dev@w3.org, Erika Feltrin <erika.feltrin@cribi.unipd.it>
Message-Id: <CD14D6CA-9A2E-4BBD-A529-1154ADAA7FA4@cs.man.ac.uk>
To: Thomas Schneider <schneidt@cs.man.ac.uk>
...but do you really need (2)? I think having all the rest should do  
the trick? Cheers, Uli

On 14 Jan 2010, at 12:00, Thomas Schneider wrote:

>
> On 14 Jan 2010, at 08:50, Rinke Hoekstra wrote:
>
>> Hi Thomas, Alessandro,
>>
>> Doesn't your (2) violate the global constraints on complex  
>> properties? You cannot have cardinality constraints on complex  
>> properties (such as chains and transitive properties).
>
> Oops ... *blush*
>
> Sorry
>
> Thomas
>
>> I myself have struggled with these kinds of modelling problems  
>> while working on my PhD. Chapter 7 of my dissertation describes  
>> ways of 'coping' with the limitations of OWL 2. See [1,2] if you're  
>> interested.
>>
>> Best,
>>
>> Rinke
>>
>> [1] http://www.leibnizcenter.org/~hoekstra/wordpress/
>> [2] http://dare.uva.nl/document/144868
>>
>> On 13 jan 2010, at 20:04, Thomas Schneider wrote:
>>
>>> Oh, just now I've read Uli's email properly ... and her suggestion  
>>> shows that this three-variable statement might be possible. Would  
>>> it be enough for your purposes if you say the following?
>>>
>>> (1) The composition of has_action_goal and  
>>> inverse(has_object_goal) implies has_object
>>> (2) Every action can have at most one object (Action subClassOf  
>>> has_object max 1 Thing)
>>> (3) All individuals of type object are distinct
>>>
>>> If (2) clashes with your scenario, it seems to me that you will  
>>> need closed world reasoning.
>>>
>>> Cheers
>>>
>>> Thomas
>>>
>>>
>>> On 13 Jan 2010, at 17:52, Thomas Schneider wrote:
>>>
>>>> Hi Alessandro,
>>>>
>>>> On 13 Jan 2010, at 11:09, Alessandro Maccagnan wrote:
>>>>
>>>>> Hi Uli,
>>>>>
>>>>> thanks for your reply.
>>>>> We are trying to define a propertyChain but we realize that what  
>>>>> we need to say is as follows.
>>>>>
>>>>> defining these properties:
>>>>> Action has_object Some Object
>>>>> Action has_action_goal Some Goal
>>>>> Object has_object_goal Some Goal
>>>>>
>>>>> at the individuals level we would like to say:
>>>>>
>>>>> a1 has_action_goal g1
>>>>> o1 has_object_goal g1
>>>>> o2 has_object_goal g2
>>>>> =>
>>>>> a1 CAN HAVE has_object o1
>>>>>
>>>>> BUT
>>>>> a1 CANNOT HAVE has_object o2
>>>>>
>>>>> So this means that only the objects (o) that have the same goal  
>>>>> (g) of the
>>>>> action (a) can be used in that action.
>>>>
>>>> I don't think that this can be said in OWL because you will have  
>>>> to say that every individual x that is related to an individual y  
>>>> via has_object must also have another link to y via the chain  
>>>> has_action_goal o inverse(has_object_goal). This statement  
>>>> requires three variables in first-order logic, hence it's  
>>>> unlikely that it can be expressed in OWL. (Or does anyone here  
>>>> see a clever trick?) You might be more lucky with a rule  
>>>> language, but that is not my domain.
>>>>
>>>> Second, together with the rule you stated in your last sentence,  
>>>> the ontology you gave is not sufficient to conclude that a1  
>>>> cannot have o2 as an object: the individuals g1 and g2 can be the  
>>>> same, and actions and objects are not prevented from having other  
>>>> goals than the ones stated. You will at least have to make all  
>>>> individuals different and close the "some" restrictions with  
>>>> corresponding "only" restrictions. Even then, the open world  
>>>> assumption might play a trick on you in the cases where you  
>>>> haven't said anything about certain individuals, so you might  
>>>> require closed world reasoning here.
>>>>
>>>> Cheers
>>>>
>>>> Thomas
>>>>
>>>>> Any suggestions?
>>>>>
>>>>> Cheers
>>>>> Alessandro
>>>>>
>>>>> On Tue, Jan 12, 2010 at 5:51 PM, Uli Sattler  
>>>>> <sattler@cs.man.ac.uk> wrote:
>>>>> Hi Alessandro,
>>>>>
>>>>> this is a tricky think to be done. What you can do is use a  
>>>>> propertychain to ensure that
>>>>>
>>>>> the composition of  has_object with has_Goal implies has_Goal.
>>>>>
>>>>> This would require the usage of a dedicated 'has_Goal' (rather  
>>>>> than a less specific has_information) property, but this  
>>>>> shouldn't be a problem (make has_information a superproperty of  
>>>>> has_Goal if you like).
>>>>>
>>>>> Does this suffice? Cheers, Uli
>>>>>
>>>>>
>>>>> On 12 Jan 2010, at 14:54, Alessandro Maccagnan wrote:
>>>>>
>>>>> Hello,
>>>>>
>>>>> we are developing an ontology for the description of a general  
>>>>> Action structure. The Action Structure is composed of:
>>>>>
>>>>> Subject (that performs the action)
>>>>> Object_complement (that undergoes the action)
>>>>> Complement (that helps in the execution of the action)
>>>>> Goal of Action (the effect of the action)
>>>>>
>>>>> We have already defined that:
>>>>>
>>>>> Action has_information one Goal_of_action
>>>>> Action has_object some Object
>>>>> Object is_object_in some Action
>>>>> Object has_information some Goal_of_action (because an object  
>>>>> can be used in several distinct actions)
>>>>>
>>>>> Now we would like to say that an Action can have as its objects  
>>>>> only those that have the same goal of the related action.
>>>>>
>>>>> Action has_object some Object where Object.Goal=Action.Goal
>>>>>
>>>>> Unfortunately we are stuck because we do not know how to  
>>>>> formalize it in OWL. Does anybody have any suggestions to help us?
>>>>>
>>>>>
>>>>> Kind regards,
>>>>>
>>>>> Alessandro Maccagnan
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> -- 
>>>>> Alessandro
>>>>> Maccagnan
>>>>
>>>> + 
>>>> ----------------------------------------------------------------------+
>>>> |  Dr Thomas Schneider                    schneider (at)  
>>>> cs.man.ac.uk  |
>>>> |  School of Computer Science       http://www.cs.man.ac.uk/~schneidt 
>>>>   |
>>>> |  Kilburn Building, Room 2.114                 phone +44 161  
>>>> 2756136  |
>>>> |  University of  
>>>> Manchester                                            |
>>>> |  Oxford Road                                             _/// 
>>>> _       |
>>>> |  Manchester M13 9PL                                       
>>>> (o~o)       |
>>>> +-----------------------------------------------------oOOO--(_)-- 
>>>> OOOo--+
>>>>
>>>> Jubones (pl.n.)
>>>> Awful things bought in Nairobi which never look good at home.
>>>>
>>>>               Douglas Adams, John Lloyd: The Deeper Meaning of Liff
>>>>
>>>>
>>>>
>>>>
>>>
>>> + 
>>> ----------------------------------------------------------------------+
>>> |  Dr Thomas Schneider                    schneider (at)  
>>> cs.man.ac.uk  |
>>> |  School of Computer Science       http://www.cs.man.ac.uk/~schneidt 
>>>   |
>>> |  Kilburn Building, Room 2.114                 phone +44 161  
>>> 2756136  |
>>> |  University of  
>>> Manchester                                            |
>>> |  Oxford Road                                             _/// 
>>> _       |
>>> |  Manchester M13 9PL                                       
>>> (o~o)       |
>>> +-----------------------------------------------------oOOO--(_)-- 
>>> OOOo--+
>>>
>>> Jubones (pl.n.)
>>> Awful things bought in Nairobi which never look good at home.
>>>
>>>                Douglas Adams, John Lloyd: The Deeper Meaning of Liff
>>>
>>>
>>>
>>>
>>
>
> + 
> ----------------------------------------------------------------------+
> |  Dr Thomas Schneider                    schneider (at)  
> cs.man.ac.uk  |
> |  School of Computer Science       http://www.cs.man.ac.uk/ 
> ~schneidt  |
> |  Kilburn Building, Room 2.114                 phone +44 161  
> 2756136  |
> |  University of  
> Manchester                                            |
> |  Oxford Road                                             _/// 
> _       |
> |  Manchester M13 9PL                                       
> (o~o)       |
> +-----------------------------------------------------oOOO--(_)-- 
> OOOo--+
>
> Jubones (pl.n.)
>  Awful things bought in Nairobi which never look good at home.
>
>                  Douglas Adams, John Lloyd: The Deeper Meaning of Liff
>
>
>
>
Received on Thursday, 14 January 2010 12:30:34 GMT

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