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Re: ISSUE-2 (All processes are systems): All processes are systems [sensor ontology - http://mmisw.org/orr/#http://www.w3.org/2009/SSN-XG/Ontologies/SensorBasis.owl - 09.12.15 ]

From: Manfred Hauswirth <manfred.hauswirth@deri.org>
Date: Wed, 16 Dec 2009 17:50:05 +0000
Message-ID: <4B291DCD.6010701@deri.org>
To: Semantic Sensor Network Incubator Group WG <public-xg-ssn@w3.org>
Hi,

as I may not be able to join today's call (50/50 chance - one of my kids 
got sick), I am starting the discussion via mail.

Let me start with a disclaimer: I generally think it is a good idea to 
stay in sync with existing standards. But I think it may be better to 
deviate if something is problematic. This is especially relevant when it 
comes to modeling an ontology, which not only should provide a concise 
classification system but also be a "natural way" (for lack of a better 
term) of modeling a domain. I the modeling is not "natural", people will 
not understand it and thus not use it.

Regarding "all systems are processes": Honestly, I would not understand 
this (I stated this at the F2F). For me, you have systems which include 
one ore more processes. If systems are processes, why have systems at 
all. My notion of systems would informally consist of processes, 
scenarios, deployments, etc.

PhysicalSystem: I don't remember the exact reason for this. Did we mean 
deployment?

Sensor as subclass of Device: I think this is too narrow. I can think of 
sensors which are not devices at all, e.g., human "sensors" in the 
context of social sensing (which is an accepted concept in many domains 
including CS by now). Making sensors a subclass of device limits us to 
purely technical systems in hardware, IMHO. Is an RSS feed a device? I 
can clearly use it as a sensor. I think that Device should be a subclass 
of Sensor. Even in existing middelware systems like our GSN we followed 
that path (without having an ontology in mind at all).

Why is a Device a subclass of a Process? A Process can use Sensors which 
are manifested as Devices to do/measure something, IMHO. Again this is a 
quite narrow notion of the concepts.

Talk to you later (hopefully),

Manfred

Semantic Sensor Network Incubator Group Issue Tracker wrote:
> 
> ISSUE-2 (All processes are systems): All processes are systems [sensor 
> ontology - 
> http://mmisw.org/orr/#http://www.w3.org/2009/SSN-XG/Ontologies/SensorBasis.owl 
> - 09.12.15 ]
> 
> http://www.w3.org/2005/Incubator/ssn/track/issues/2
> 
> Raised by: Luis Bermudez
> On product: sensor ontology - 
> http://mmisw.org/orr/#http://www.w3.org/2009/SSN-XG/Ontologies/SensorBasis.owl 
> - 09.12.15
> 
> In SensorML all systems are processes, but in our case we can say that 
> all processes are systems. And all the other classes (types of systems 
> and processes) should be subclass of both. Suggestion:
> 
> - Move Sensor to be subclass of Device
> - Remove PhysicalSystem - not needed
> - Move Device to be subclass of Process
> 
> 
> 
> 

-- 
Prof. Manfred Hauswirth
Digital Enterprise Research Institute (DERI)
National University of Ireland, Galway (NUIG)
http://www.manfredhauswirth.org/
Received on Wednesday, 16 December 2009 17:50:50 GMT

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