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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: Tue, 22 Dec 2009 19:10:40 +0000
Message-ID: <4B3119B0.7020402@deri.org>
To: Luis Bermudez <bermudez@sura.org>
CC: John Graybeal <jbgraybeal@mindspring.com>, Semantic Sensor Network Incubator Group WG <public-xg-ssn@w3.org>
Looks fine to me. The only item I am really having trouble with is "a 
sensor is a process". Since I wanted to test, if I am the only person 
who could not understand this, I tested it around here: 100% had the 
proverbial question marks written on their faces (mostly CS people, some 
with a science back ground - physics).

Just wanted to flag this. Seems a pretty strong indicator to me though. 
However, If this is the consensus of the group it to go with it, I am OK 
  with it (still feels strange for me though).

Cheers,

Manfredd

Luis Bermudez wrote:
> Can we make some conclusions, in particular those of you discussing this 
> thread ?
> 
> I agree with all of these:
> 
> - A process has inputs and outputs
> - A system has components
> - A sensor is a process
> - *Some* devices are sensors
> - *Some* devices are systems
> 
> 
> -luis
> 
> On Thu, Dec 17, 2009 at 3:11 AM, John Graybeal 
> <jbgraybeal@mindspring.com <mailto:jbgraybeal@mindspring.com>> wrote:
> 
> 
>     On Dec 16, 2009, at 12:00, Manfred Hauswirth wrote:
> 
>         Hi John,
> 
>         thanks for your insightful comments. Some more comments from my
>         side.
> 
>         John Graybeal wrote:
> 
>              > 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.
>             The question "why have systems at all?" is the crux here.
>              Can we state clearly when a process is not a system? Or in
>             other words, how is a system more narrow than a process?
>             Incidentally, my notion of processes would informally
>             consist of the same list.  I am also having trouble drawing
>             the distinction.
> 
> 
>         Interesting! I think this may be due to our different background
>         (I assume your are not a computer scientist like myself -
>         without evidence I may add).
> 
> 
>     Computer Science and Statistics. 30 years software and systems
>     support.  (No worries!)
> 
> 
>         In my area (computer science, information systems) systems would
>         be defined as I do and a system would consist of software and
>         hardware and the processes would clearly be "inside" the system
>         as part of the software, so there is a clear distinction between
>         "system" and "process" (other CS/IS people - please feel free to
>         contradict me), whereas you seem to define this more from the
>         viewpoint of an experiment which is being observed (?) where
>         processes come into play as part of the observation process
>         (please correct me - I am guessing here).
> 
> 
>     I'm using one of the general meanings of the word 'process', which
>     applies not just to what's happening in side the computer or
>     component, but what happens as all the software and components
>     interact with each other.  There are local processes and there are
>     external processes.
> 
>     It isn't driven by experiment orientation but by broader CS
>     orientation -- dealing with engineering systems of systems, and
>     including the human component in those systems, and modeling all the
>     above as processes (which may, or may not, then be computerized in
>     the new version of the system).  Anyway, just a different viewpoint,
>     neither right nor wrong.
> 
> 
>         The problem here seems to lie in different conceptualizations in
>         different communities - all of which done according to the
>         specific needs of a community. Now, while this may complicate
>         things, I think it is also a useful and actually mandatory
>         exercise. While I may claim, that I need to understand the
>         conceptualization because as an CS/IS person I will have to
>         build (software/hardware) systems (sorry! no other term comes to
>         mind) which need to manage information coming out of
>         observations, you may claim exactly the same from you point of
>         view (and rightfully so). The question now for me is: Who are
>         our users and how to serve them best? Where's the sweet spot?
> 
> 
>     Concur. I presumed from the start that the group was interested in
>     modeling hardware elements, but I have found it useful to consider
>     those hardware components as processes in a larger system of
>     systems. They take data in and transform it to other data that is
>     spit out. This is one useful definition of a process, as Luis notes.
> 
>     Oops, got off track there! But our agreed point is to agree on which
>     type of devices (= which group of users) we want to make the
>     ontology for.  My assumption/preference was the group that used
>     physical devices to transform measurable phenomena into digital data
>     (because that's the easiest to model and the most immediately
>     useful).  But I can go with whatever on this, as long as we all
>     understand.
> 
> 
>              > PhysicalSystem: I don't remember the exact reason for
>             this. Did we  > mean deployment?
>             I assume this is to distinguish it from a software system.
>              > 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).
>             This gets to purpose of the ontology.  As I understood it,
>             the group was originally constructed to model hardware
>             sensors. (May have just been a wrong assumption on my part.
>              More precisely, what we clearly were not doing is modeling
>             samplers, that is, devices that return a physical sample.)
> 
> 
>         Agreed. But "sensors" do not necessarily manifest themselves as
>         hardware. If I want to detect user activity / inactivity on a
>         computer in an experiment, one of my sensors may be a the
>         keyboard, another one running processes (not waiting for user
>         input), etc. It is very hard to draw the line here. My question:
>         Do I have to have this distinction at all? Essentially I convert
>         an X into a Y and Y should be usable in a computer. Whether X a
>         is a physical phenomenon or not depends on the domain, IMHO.
> 
> 
>     Sure, that works for me too.  If you make a sensor too general,
>     though, it can have components. What do we call those components --
>     are not at least some of them sensors?  So now, what is different
>     from the sensor that can have sensors, and a device, which has the
>     same recursion into smaller devices; and a system, which can have
>     systems (and a process, that can have processes)?
> 
>     I'm being a little silly of course.  All I mean to do is call
>     attention to the need to define the terms according to what makes
>     them different from each other, not just whether they are higher or
>     lower in a hierarchy. I think we haven't done that well enough yet.
> 
> 
>             So using one definition of sensor ("anything that senses")
>             makes Sensor very broad, and other things would subclass to
>             it. (Since some devices (a hammer) don't sense things, we'll
>             have to define Device narrowly to make it a subclass
>             Sensor.)  Using another definition of sensor ("a component
>             that detects (measures) a physical phenomenon, converting it
>             into a digital representation that can be output to other
>             components"), a Sensor is clearly a specific type of Device,
>             and is also a component of any sensing device.
> 
> 
>         If you see software as a Device, I would agree to it, but then
>         again Device has the connotation of hardware.
> 
> 
>     Ah, I said a Sensor was hardware in my original world, so I didn't
>     have any problem here -- since my Sensor was hardware and my Device
>     had a sensor, I was already on board with Device being hardware.
> 
> 
>             Do we have a set of definitions by any chance, so we can all
>             use these (or some) terms the same way?
> 
> 
>         I don't think we have.
> 
>              > 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.
>             I'm not following your argument here.  Yes, a Process can
>             use Sensors as you say. So can a Device.  There is no
>             inconsistency that I can see.  This suggests a Device is in
>             fact a type of Process.
> 
> 
>         Sorry, but I don't understand how a Device can be a Process.
> 
> 
>     The "Process: something that receives an input and produces an
>     output" is not a sufficient explanation or model of that?
> 
>     John
> 
> 
>         Best regards,
> 
>         Manfred
> 
> 
> 
> 
> 
> 
> -- 
> Luis Bermudez Ph.D.
> Coastal Research Technical Manager
> Southeastern Universities Research Association (SURA)
> bermudez@sura.org <mailto:bermudez@sura.org> - Office: (202) 408-8211
> 1201 New York Ave. NW Suite 430, Washington DC 20005

-- 
Prof. Manfred Hauswirth
Digital Enterprise Research Institute (DERI)
National University of Ireland, Galway (NUIG)
http://www.manfredhauswirth.org/
Received on Tuesday, 22 December 2009 19:11:22 GMT

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