- From: Sebastian Samaruga <cognescent@gmail.com>
 - Date: Tue, 13 Jan 2015 21:03:50 -0300
 - To: "Eric Prud'hommeaux" <eric@w3.org>
 - Cc: "semantic-web@w3.org" <semantic-web@w3.org>, "pragmaticweb@lists.spline.inf.fu-berlin.de" <pragmaticweb@lists.spline.inf.fu-berlin.de>
 - Message-ID: <CAFnmbpWgZeDKrtxBBsg3QQXqqB1z8qWFSm1ZiPMjduoYsrGwXw@mail.gmail.com>
 
I've updated the repository and now there is an executable WAR file for
testing in servlet containers. There are also the complete sources which
haven't been correctly uploaded.
Project: https://code.google.com/p/cognescent/
(in source section are instructions for checking out via svn).
Best,
Sebastian.
On Sun, Jan 11, 2015 at 2:24 PM, Sebastian Samaruga <cognescent@gmail.com>
wrote:
> Yes, is true. I haven't reached at that point yet and I understand that
> recording the inferences I make in OWL would be a lot helpful, mostly
> because I try to merge diverse sources and also augment knowledge with
> linked data and upper ontologies. My reason for haven't using those
> features yet is because I only use 'plain' RDF to infer metadata. Only SPO
> triples with no schema information are my sources of data. And, once there,
> my model allows the assertion of one subject in one role or occurrence to
> be referred under some kind of type (or, at least, I try).
>
> But it will help a lot if, once I infer properties, types and class
> restrictions, I put them in OWL so I can reuse them later or use them for
> further inference. Thanks a lot for your advice, I'll taking it into
> account. And, as I said before, my tools and my skills limit me somehow so
> your knowledge is really helpful.
>
> Best,
> Sebastian.
>
>
> On Sun, Jan 11, 2015 at 3:58 AM, Eric Prud'hommeaux <eric@w3.org> wrote:
>
>> * Sebastian Samaruga <cognescent@gmail.com> [2015-01-10 18:22-0300]
>> > Hi, sorry for the delay in the response too.
>> >
>> > Yes, maybe I'm ambitious. And maybe I don't have all the tools/skills I
>> > need at hand when I try to develop or communicate my ideas.
>> >
>> > I was surprised when someone told that only using RDF Schema is
>> possible to
>> > infer types. Actually, I'm currently inferring type information on
>> > arbitrary sets of entities using only their properties information.
>> When I
>> > know that many subjects share the same set of properties I can be
>> allowed
>> > to think that they belong to the same class. And when they share the
>> same
>> > values for their properties, I can infer they are in a similar 'state'
>> > (i.e.: single / married, student / employee, etc).
>>
>> Minor (perhaps orthogonal) point: RDFS doesn't enable one to infer
>> types in the sense that you are using; it simply has some rules used
>> to infer types, e.g.
>>   { W <p1> X . <p1> rdfs:domain Y . } implies { W rdf:type Y } .
>>   { W <p1> X . <p1> rdfs:range  Z . } implies { X rdf:type Z } .
>>
>> OWL enables you write nuanced rules, e.g. every X of type Doctor who
>> is treating some patient most also be a PracticingDoctor. This may
>> address some of the "context" which Pat warned you about below by
>> capturing the constraints for that context in a computable structure.
>>
>> If you know in advance the properties you are examining and the
>> criteria for inferring types, you can probably record most of that in
>> OWL. If your process examines a graph and clusters nodes based on
>> similarity, (perhaps with some human oversight looking at the
>> instances to say "I'll call those PracticingDoctors", you can probably
>> record those discovered criteria in OWL.
>>
>> Take a peek at the OWL primer to see if it applies to your work
>> <http://www.w3.org/TR/owl2-primer/>. Note that
>> <http://www.w3.org/TR/owl2-primer/#OWL_Syntaxes> provides a switch for
>> what languages are displayed; for this forum, turtle syntax will reach
>> the broadest audience.
>>
>>
>> > Using RDF as the core format where many data sources converge, and this
>> > kind of metadata information from the RDF I'll try to observe
>> 'Concepts' to
>> > which classes/types belong. It's a kind of role or meta class where some
>> > instances of Things are classified. Things are abstract subjects of
>> > discurse of what references or Signs can be made of. For example, Woody
>> > Allen has an occurrence (manifestation of existence) as the director
>> > (concept / role) of some movie (another Thing).
>> >
>> > The goal is to be able to take note of all of those relationships in a
>> kind
>> > of index where equivalences between different sources of data talking
>> about
>> > the same subjects, in a different vocabulary, can be deduced. This is
>> the
>> > intention of many Semantic Web projects already, and this metadata
>> > (de)aggregation would benefit a lot from linked data sources.
>> >
>> > Luckily I could develop an (ongoing) proof of concept project of what I
>> > propose, which I'm hosting at googlecode:
>> >
>> > https://code.google.com/p/cognescent/ (checkout sources only in the CBI
>> > folder)
>> >
>> > It's a Java Web Application project with instructions in how to exec in
>> the
>> > README. It's a work in progress. It provides an OData frontend, browse
>> > service document, instances and metadata, all from any RDF datasource.
>> It
>> > can also be configured to use a relational database modifying Main.java
>> > manually (for now). It translates the relational data to RDF to perform
>> > model set up.
>> >
>> > Best regards,
>> > Sebastian.
>> >
>> >
>> > On Fri, Oct 10, 2014 at 10:20 AM, Thierry BIARD, EIRL AMBESAS <
>> > thierry.ambesas@gmail.com> wrote:
>> >
>> > > Hi Sebastian,
>> > >
>> > >
>> > >
>> > > I hope you are fine. Sorry for the delay of response. As far as RDF is
>> > > concerned, I am not good enough to discuss this matter. I suppose
>> that Pat
>> > > Hayes is an expert and that his comments are relevant and will help
>> you on
>> > > your ambitious demarche. You are not of those who give up. I know
>> that you
>> > > will continue.
>> > >
>> > >
>> > >
>> > > Best regards.
>> > >
>> > >
>> > >
>> > > Thierry
>> > >
>> > >
>> > >
>> > > *De :* Sebastian Samaruga [mailto:cognescent@gmail.com]
>> > > *Envoyé :* mercredi 17 septembre 2014 19:55
>> > > *À :* Pat Hayes
>> > > *Cc :* Thierry BIARD, EIRL AMBESAS; semantic-web@w3.org;
>> > > pragmaticweb@lists.spline.inf.fu-berlin.de
>> > > *Objet :* Re: Micellaneous
>> > >
>> > >
>> > >
>> > > Ok, I should have stated that this is intended to build an API in some
>> > > language to perform the mentioned operations.
>> > >
>> > > Aggregating URIs means that if they occur multiple times in a closed
>> world
>> > > model in which I know all the statements then I can be sure that they
>> > > represent the same thing. Another task of a given ETL tool could be
>> perform
>> > > merging and mapping of some kind, maybe to an upper ontology to
>> facilitate
>> > > this task.
>> > >
>> > > The algorithm for types is there and it is working. Those are inferred
>> > > types and as in the previous paragraph I suppose a closed world like,
>> for
>> > > example, and RDF dump of a relational database. This closed world
>> > > assumption can be relaxed having the possibility of merging multiple
>> > > documents in the ETL component.
>> > >
>> > > Methods and contexts refer to the to be implemented API. Sorry for
>> not be
>> > > clear enouth about that. And Resource class methods (getXXX) receive
>> the
>> > > context as their arguments which can be one of the tree possible
>> arguments
>> > > listed. Subclasses (Concept, Thing, Sign) may override this behavior..
>> > >
>> > > Best,
>> > > Sebastian Samaruga.
>> > >
>> > >
>> > >
>> > > On Wed, Sep 17, 2014 at 2:13 PM, Pat Hayes <phayes@ihmc.us> wrote:
>> > >
>> > >
>> > > On Sep 17, 2014, at 9:30 AM, Sebastian Samaruga <cognescent@gmail.com
>> >
>> > > wrote:
>> > >
>> > > > Thierry, thanks really for your time answering my emails. I didn't
>> take
>> > > the online course. Although I've spending some of my time in some
>> kind of
>> > > semantic (semiotic) metamodel for what I understand as knowledge
>> > > representation..
>> > > >
>> > > > I'm copying this mail to the liists.
>> > > >
>> > > > For what I came with, the core concepts, borrowed from semiotics,
>> are:
>> > > > 1. Concept
>> > > > 2. Thing
>> > > > 3. Sign
>> > > >
>> > > > First, a Sign is an occurrence of a Thing in some context. For
>> example,
>> > > in RDF, some URI referring something that somehow exist.
>> > > >
>> > > > A Thing is something that can exist and, given that notion, can
>> appear
>> > > in occurrences of some kind. A thing also aggregates all of its
>> occurrences
>> > > as they represent the Thing as a whole.
>> > > >
>> > > > Finally, a Concept is an abstraction of a set of Things. Things are
>> > > instances of Concepts and, again, which Concept they are instance of
>> is
>> > > context dependent. A Thing could be regarded as an occurrence of a
>> Concept.
>> > > >
>> > > > So, given that I begin with Things and I need a source of them I can
>> > > begin with some RDF source without the need of any schema embedded in
>> it.
>> > > The URIs in the triples are Signs.
>> > >
>> > > OK so far, although RDF does not support contexts, so a given IRI is
>> > > assumed to denote the same thing everywhere it occurs.
>> > >
>> > > > Aggregating all occurrences of the same URI I came up with the Thing
>> > > they represent.
>> > >
>> > > ? How does that work? What do you mean by 'aggregating'? And how can
>> you
>> > > know if you have all the occurrences of a given IRI, on the entire
>> Web?
>> > > (You can't possibly know this.)
>> > >
>> > > > Then using a simple algorithm of which URIs share the same
>> predicates I
>> > > can infer the type of the URIs and came up with the Concepts.
>> > >
>> > > That is not going to work, because you would also need to know the
>> domain
>> > > and range properties of those predicates, and that information is not
>> > > always given explicitly. At the very least, you will need RDFS or OWL
>> type
>> > > reasoning here.
>> > >
>> > > >
>> > > > Now, the meta model:
>> > > > The core concepts inherits from a Resource class. This parent class
>> has
>> > > the following methods:
>> > >
>> > > "methods"? That term is not meaningful in RDF.
>> > >
>> > > >
>> > > > Resource::getSigns(Sign | Thing | Concept) : Occurrences of argument
>> > > > Resource::getThings(Sign | Thing | Concept) : Instances of argument
>> > > > Resource::getConcepts(Sign | Thing | Concept) : Classes / roles of
>> > > argument.
>> > > >
>> > > > Example data:
>> > > > aPerson :employment anEmployment (Signs)
>> > > > Peter :employment SalesDptManager (Thiings)
>> > > > Person, Employe :employment Employment, Position (Concepts)
>> > > >
>> > > > So, care must be taken building an ETL RDF tool that populates this
>> > > bindings in Resource instances, provides querying facilities and
>> support
>> > > the construction of entities which apply rules-transformation kind of
>> > > behavior using 'template' resources.
>> > > >
>> > > > Then the model should allow to build queries navigating Resource
>> APIs
>> > > like retrieving all the Concepts a Thing plays in a context, which
>> Signs
>> > > are instances of a given Thing in a given Concept context, etc.
>> > >
>> > > To repeat, there are no contexts in RDF.
>> > >
>> > > I would strongly recommend that you read more about RDF and its
>> intended
>> > > semantics before proceeding.
>> > >
>> > > Best wishes
>> > >
>> > > Pat Hayes
>> > >
>> > > >
>> > > > Best,
>> > > > Sebastian Samaruga..
>> > > >
>> > >
>> > > ------------------------------------------------------------
>> > > IHMC                                     (850)434 8903 home
>> > > 40 South Alcaniz St.            (850)202 4416   office
>> > > Pensacola                            (850)202 4440   fax
>> > > FL 32502                              (850)291 0667   mobile
>> (preferred)
>> > > phayes@ihmc.us       http://www.ihmc.us/users/phayes
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >
>>
>> --
>> -ericP
>>
>> office: +1.617.599.3509
>> mobile: +33.6.80.80.35.59
>>
>> (eric@w3.org)
>> Feel free to forward this message to any list for any purpose other than
>> email address distribution.
>>
>> There are subtle nuances encoded in font variation and clever layout
>> which can only be seen by printing this message on high-clay paper.
>>
>
>
Received on Wednesday, 14 January 2015 00:04:56 UTC