Transcript Class exercise II: Use Case Implementation Deborah McGuinness and Joanne Luciano With Peter Fox and Li Ding CSCI-6962-01 Week 7, October 18, 2010

Class exercise II: Use Case
Implementation
Deborah McGuinness and Joanne Luciano
With Peter Fox and Li Ding
CSCI-6962-01
Week 7, October 18, 2010
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Contents
• Review of use case presentations,
questions, comments
• Implementing a use case – this is where
it can get tough and complicated for
semantics
• Summary
• Next week
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Semantic Web Methodology and
Technology Development Process
•
•
Establish and improve a well-defined methodology vision for
Semantic Technology based application development
Leverage controlled vocabularies, et c.
Adopt
Leverage
Science/Expert
Rapid
Technology
Open World: Prototype Technology
Review & Iteration
Approach
Infrastructure
Evolve, Iterate,
Redesign,
Redeploy
Use Tools
Evaluation
Analysis
Use Case
Small Team,
mixed skills
Develop
model/
ontology
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Implementation Basics
• Review your use case with team and experts
• Go into detail of your ontology; test it using the
tools you have
• We will look at the use case document and
examine the actors, process flow, artifacts, etc.
• You will start to develop a design and an
architecture (more on architecture and middleware
next week)
• Keep in mind that it is more flexible to place the
formal semantics withinin your interfaces, i.e.
between layers and components in your
architecture or between ‘users’ and ‘information’ to
mediate the exchange
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Actors
• The initial analysis will often have many human
actors
• Look to see where the human actors can be
replaced with machine actors – many will
require additional semantics, i.e. knowledge
encoding
• If you are doing this in a team, take steps to
ensure that actors know their role and what
inputs, outputs and preconditions are expected
• Often, you may be able to ‘run’ the use case
(really the model) before you build anything
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Process flow
• Each element in the process flow usually
denotes a distinct stage in what will need to
be implemented
• Often, actors mediate the process flow
• Consider the activity diagram (and often a
state diagram) as a means to turn the
written process flow into a visual one that
your experts can review
• Make sure the artifacts and services have
an entry in the resources section
• Often the time you may do some searching
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Preconditions
• Often the preconditions are very syntactic
and may not be ready to fit with your
semantically-rich implementation
• Some level of modeling of these
preconditions may be required (often this will
not be in your first-pass knowledge encoding,
which focuses on the main process flow, i.e.
goal, description, etc.)
• Beware of using other entities data and
services: e.g., policies, access rights,
registration, and ‘cost’
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Artifacts
• Add artifacts that the use case generates to the
resources list in the table
• It is often useful to record which artifacts are
critical and which are of secondary importance
• Be thinking of provenance and the way these
artifacts were produced, i.e. what semantics
went into them use this information to produce
suitable metadata or annotations
• Engage the actors to determine the names of
these artifacts and who should have
responsibility for them (usually you want the 8
actors to have responsibility for evolution)
Reviewing the resources
• Apart from the artifacts and actor resources,
you may find gaps
• Your knowledge encoding is also a resource,
make it a first class citizen, i.e. give it a
namespace and a URI
• Often, a test-bed with local data is very useful
at the start the implementation process, i.e.
pull the data, maybe even implement their
service (database, etc.)
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Back to the knowledge encoding
• Declarative: in CL, OWL (probably OWL-DL),
RDF, SKOS?
• Need rules?
• Need query?
• Science expert review and iteration
• Means you need something that they can
review, with precise names, properties,
relations, etc.
• The knowledge engineering stage is much
like a software engineering process
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Knowledge engineering
• Classes 2, 3, 5 and 6
• Mostly choose OWL-DL (and OWL 2)
• We may need to go to OWL 2 for numerical
comparisons and if so, separate your owl 1
from OWL 2 representations
• The interplay between tools like Protégé and
CMAP will be very important in implementing
a knowledge base that has ‘just enough’
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Implementation Basics
• Review documented use case now
• Go into detail of the ontology
• Now we will look at the use case document and
examine the actors, process flow, artifacts, etc.
• Start thinking of a design and an architecture
• Semantics between/ in your interfaces
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Roles and skill-sets
• Facilitator – changes slightly for implementation sometime the facilitator becomes chief architect,
sometimes steps back
• Domain experts are needed for expert review
(domain literate, know resources; data,
applications, tools, etc)
• You are the modeler (to extract objects, triples)
• You are likely to play the role of a software
engineer (architecture, technology) but you can
also ask someone for help with this
• Document, document, document
• It is social – a team effort
Use case roles and skill-sets
• Time for a self assessment
• We will scope for the purpose of
learning how to …
Implementing
• Let’s take a few examples
– VSTO
– BCO-DMO
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Summary
• By now, the reality of going into complete
detail for the knowledge representation
should be apparent
• Keeping it simple is also very important as
you begin to implement
• Being prepared to iterate is essential
• Now is the time to validate your ontology with
domain experts and your team, use the tools
• The next stage is to choose your technology
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components and build and test
Environmental Cleanup
• To determine the hazardous waste sites in New
York State that contained VOC contamination at or
above their federal guidance value in groundwater
and were remediated via Soil Vapor Extraction.
• The goal of this use case is to provide technical
staff and stakeholders with the ability to access data
for hazardous waste remediation sites across New
York State. It allows project managers to find and
analyze sites similar to their own in order to make
better decisions. It also improves the ability to
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collaborate both internally and externally.
Domain expert
• Chris + ?
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Deep Sea Research Preparation
• An oceanographer is preparing for a cruise
that will be making use of one of the National
Deep Submergence Facility vehicle (operated
by the Woods Hole Oceanographic
Institution). They will be diving in the
Galapagos hot vent area and want to:
– see an organized list of links to related publications,
Oceanus articles, data library holdings, video snapshot
sequences, and any other datasets available in the
various repositories.
– get a list of researchers who have published journal
articles about this particular area.
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DSRP Resources
• Bibliography of all journal articles that mention one
of the deep submergence vehicles by name
• Text of some of the articles from the bibliography
• A CSV file containing a list of Oceanus magazine
articles and keywords associated with these articles
• An inventory of video and still imagery held by the
data library
• The Alvin Vehicle Framegrabber website (with video
snapshots available)
• The Jason Virtual Control Van website (with video
snapshots available)
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More resources
• NDSF bibliography link -http://dlaweb.whoi.edu/DIG_RES/NDSF_bib.
html
• Holdings spreadsheet
• Jason control van website -http://4dgeo.whoi.edu/jason/alvin
• Framegrabber -- http://4dgeo.whoi.edu/alvin
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Domain experts
• Andy Maffei, Lisa Raymond (WHOI)
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Assignment 3
• Team use case implementation
– On the wiki
– Write up and presentation
– Due November 22
• Team 1: Environmental Cleanup
– Chris, Xiang, Jim, Shankar
• Team 2: Deep Sea Research Preparation
– Eric, Yongmei, Selcuk, Tim
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Next week
• This weeks reading assignment:
– reading: IAAI VSTO, Semantic eScience Web
Services and C&G paper
• Next class (week 8 – October 25):
– Foundations V: Infrastructure and Architecture,
Middleware
• Questions?
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