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Finding sustainability data on the Web. David Leal CAESAR Systems Limited [email protected]. Using emerging technologies. Identifying things by HTTP URIs getting data about them by “ dereferencing ” Data as RDF statements readable RDF as N3 - PowerPoint PPT Presentation
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Using emerging technologies
• Identifying things by HTTP URIs– getting data about them by “dereferencing”
• Data as RDF statements– readable RDF as N3– a little bit of formality from OWL
• The importance of standard RDF vocabularies– This is what will make it work– This is our task
About URIs• a URI is just a string of characters
– They are unique identifiers for things, which are used on the web– A thing can have more than one URI, but a URI identifies only one
thing
• HTTP URI– formerly called a URL– The use of an HTTP URI implies that an HTTP (HyperText Transfer
Protocol) access, e.g. from a browser, is valid– But you may be disappointed and get “error 404” – no answer was
the stern reply
• a URN– A URI which does not imply any form of access– used by some organisations – e.g. ISO, ISBN– urn:iso:std:iso:15926:-2
The Web is based upon HTTP URIs – don’t worry about URNs
What a URI identifies
• a web page– http://www.iom3.org/index.htm– You can open it with your browser – data is downloaded– You can follow links to other web pages
• an object– http://www.iom3.org/– This is the organisation Institute of Materials, Minerals and Mining– It has a Royal Charter – it cannot be downloaded to a browser
• a formula– http://www.iom3.org/formula.n3– This is a computer interpretable file of RDF statements about the
IoM3– It can be process by Semantic Web browser or by an application
Uniform Resource Identifier
Dereferencing a URI
• If the URI identifies a web page – you get it
• If the URI identifies an RDF formula – you get it
• It the URI identifies an object ....– The object could be the Eiffel Tower, or the Institute of Materials –
neither can be downloaded to your browser– either you get nothing (error 404), or you are redirected to
a “representation”
“dereferencing” means attempting to get some data. You can only dereference an HTTP URI.
access to http://www.iom3.org/ is redirected to http://www.iom3.org/index.htm
Semantic Web technologies
• RDF (Resource Description Framework)– making statements on the Web– http://www.w3.org/RDF/
• N3 (Notation 3)– a simple way of writing down an RDF statement– http://www.w3.org/TeamSubmission/n3/
An opportunity to:
• record information more simply• enable others to use our concepts• use the concepts of others
Jane
believes
Getting started
Janet Johnloves
RDF diagram
N3
:Janet :loves :John .:Jane :believes { }
Getting started
people:Janet relationship:loves people:John .
@prefix people: <http://www.friends-are-us.com/registry/> .
@prefix relationships: <http://www.institute-of_relationships.org/vocabulary#> .
namespacesidentify the people
identify the human relationships
….. or as XML
<?xml version="1.0"?><!DOCTYPE rdf:RDF [ <!ENTITY rdf "http://www.w3.org/1999/02/22-rdf-syntax-ns#"> <!ENTITY people "http://www.friends-are-us.com/registry/"> <!ENTITY relationships "http://www.institute-of_relationships.org/vocabulary#">]>
<rdf:RDF xmlns:rdf="&rdf;" xmlns:relationships="&relationships;">
<rdf:Description rdf:about="&people;Janet"> <relationships:loves rdf:resource="&people;John“/> </rdf:Description>
</rdf:RDF>
no more precise – and not as readable
Clever browsershttp://www.iom3.org/index.htm
click to view the formula
The IoM3 has not implemented this – yet
Clever browsers
Suppose you want a formula
• Usually redirection takes you to an HTML web page
– This is good, because a person may need to know what a URI identifies – the web page can tell him or her
• If an application want the formula, then there are two options:
– content negotiation – the HTTP protocol allows the GET request to specify the required format – RDF can be specified
– link from the HTML file – this is hidden in the header and is used by applications when required
Suppose you want a formulahttp://www.iom3.org/index.htm
link to the formula
<html> <head> <title>IOM3 - Institute of Materials, Minerals and Mining</title>
<link rel="alternate" type="application/rdf+xml" title="RDF Representation" href="http://www.iom3.org/formula.n3" />
<meta name="description" content="Institute of Materials, Minerals and Mining“/>
<meta name="keywords" content="IOM3, IOM, IMM, materials, world, academy, profession, science, engineering, metals, ceramics, polymers, glass, rubber, minerals, mining, plastics, institute, careers, jobs, journals, education"/>
......
Suppose you want a formulahttp://www.iom3.org/formula.n3
@prefix con: <http://www.w3.org/2000/10/swap/pim/contact#>.@prefix tabont: <http://dig.csail.mit.edu/2005/ajar/ajaw/ont#> .@prefix foaf: <http://xmlns.com/foaf/0.1/> .@prefix dc: <http://purl.org/dc/elements/1.1/> .
<http://www.iom3.org/> a eng-sci:EngineeringInstitution ; dc:title "Institute of Materials, Minerals and Mining" ; con:phone <tel:+44 (0)20 7451 7300> ; foaf:webpage <http://www.iom3.org/index.htm> .
<http://www.iom3.org/congress-2008> a eng-sci:Conference ; dc:title "Materials Congress 2008 - Materials for the Future" ; tabont:isMentionedIn <http://www.iom3.org/congress-2008/formula.n3> .
......
vocabulary about engineering organisations
and events
An individual producthttp://packing-machinery.cn/item/08-12345
item/08-12345
Ruian Zhuxin Machinery Co. Ltd.manufactured by
type
model/ML1800
– person readable nameplate
– bar code
– RFID
specified as:
An individual producthttp://packing-machinery.cn/item/08-12345
@prefix rzm: <http://packing-machinery.cn/> .@prefix iso: <http://www.tc184-sc4.org/vocabulary#> .
http://packing-machinery.cn/item/08-12345/formula.n3
dereference to get a formula about the model
rzm:item/08-12345 iso:manufacturedBy <http://packing-machinery.cn> ; a rzm:model/ML1800 .
A class of producthttp://packing-machinery.cn/model/ML1800
@prefix rzm: <http://packing-machinery.cn/> .@prefix iso: <http://www.tc184-sc4.org/vocabulary#> .@prefix packing <http://www.packing.association.org/vocabulary#> .
http://packing-machinery.cn/model/ML1800/formula.n3
rzm:model/ML1800 iso:hasMass [ scale:kilogram 14000] ; packing:maximum_rule_length [ scale:metre 50 ] ; packing:speed [ scale:perMinute 16 ] ; packing:motorPower [ scale:kilowatt 11 ] ; ......
who defines the vocabularies?– an ISO or IEC committee– a trade association
The Ruian Zhuxin Machinery Co has not
implemented this – yet – as far as I know
LCA data in the formulahttp://packing-machinery.cn/model/ML1800
http://packing-machinery.cn/model/ML1800/formula.n3
• Each item of model ML1800 requires:– emissions of 25 kg CO2 to produce;– emissions of -4 kg CO2 to dispose (negative because recycling displaces mineral
extraction);– emission of 0.001kg CO2 per hour to run (European electricity generation mix).
LCA data in the formulahttp://packing-machinery.cn/model/ML1800
http://packing-machinery.cn/model/ML1800/formula.n3
rzm:model/ML1800 lca:unitProductionCO2emission [ scale:kilogram 25 ] ;
lca:unitDisposalCO2emission [ scale:kilogram -4 ] ;
lca:hourUseCO2emission [ scale:kilogram 0.001 ] .
actually it is more complicated
Actually it is more complicated
ML1800
flow 1
output flow
manufacture of 1ML1800 item
reference output
atmosphere
CO2
destination
material
substance
25 kg
amount
flow 2
SO2
material
substance
0.01 kg
amountdestination
flow 3
output flow output flow
objects and relationships defined in ISO 14048
but not different in principle
Actually it is more complicated
rxm:process/ML1800
lca:hasOutputFlow
[ a lca:ReferenceFlow ;
lca:destination lca:Technosphere ;
lca:material [ lca:loadOf rxm:model/ML1800 ;
lca:numberInLoad 1 ] ] ;
lca:hasOutputFlow
[ lca:destination lca:Atmosphere ;
lca:Material [ a iupac:CarbonDioxide ;
lca:amount [ scale:kilogram 25 ] ] ] ;
lca:hasOutputFlow
[ lca:destination lca:Atmosphere ;
lca:Material [ a iupac:SulfurDioxide ;
lca:amount [ scale:kilogram 0.01 ] ] ] ;
......
vocabulary for LCA from ISO 14048
URI for substances from somewhere?
Making this work
• Material products have HTTP URIs– A new business process
• Dereferencing gives:– Web page of information about the product – Web 1.0– RDF formula about the product – Web 3.0
• Standard vocabularies to use in the formulae– Vocabularies for product properties– Vocabularies for LCA
• LCA data published using the same approach– Products have URIs, dereferencing give LCA data
Navigating the supply chain
LCA catalogues (e.g. EU LCA InfoHub) linked to industrial catalogues
class A class B class C class D class D
product
supply 1
supply 2
supply x
supply y
supply z
subclass of
LCA data fromanalysis of supply
subclass of
subclass of
LCA data fromanalysis of supply
Ends