Model-Based%20Workflows

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Model-Based Workflows

• Leonardo Salayandía
• University of Texas at El Paso

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Overview

• Context
• Cyberinfrastructure for scientific domains
• SOAs, service composition, and workflows
• A Domain-Specific Modeling approach
• The model Workflow Driven Ontologies (WDOs)
• The DSL Model-Based Workflows (MBWs)
• Status

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Context

• Cyberinfrastructure for the Geosciences (GEON)
• Nation-wide NSF-funded project http//www.geongrid
  .org
• Scientist collaborators
• Creating ontologies to describe scientific
  domains
• IT collaborators
• Creating distributed resources across geosciences
  domains in the form of services (SOA)
• Creating workflows to compose services into
  scientific applications
• The DSM challenge
• Bridging the gap between ontologies and workflow
  creation

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Ontologies

• Scientists create the Domain Specific Model
• OWL Ontology Web Language (W3C)
• Workflow Driven Ontologies (WDOs)
• Define a context for scientists to create
  ontologies that are amenable to workflow
  generation
• WDO creation software
• Brainstorming phase to define information and
  method concepts
• Relationship elicitation phase to define
  input/output relationships between information
  and methods concepts

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Workflows

• IT professionals and scientists create workflows
  from services
• Workflow languages not targeted for scientists
• OWL-S (Semantic Web), MoML (Ptolemy II, Kepler)
• Kepler Scientific Workflow Management System
• Graphical abstraction of workflow language (MoML)
• Closer to being used by scientists, but not there
  yet

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OWL-S example
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Kepler Workflow example
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Model Based Workflows

• Contains terms defined by the scientist (not
  computer science terms)
• Data types defined based on the scientists terms
• Abstract level of specification
• Not an executable DSL
• Scientist can be sloppy about workflow
  specification, ex. partial orders
• Scientists can understand the workflows,
  validate, and give feedback to the Workflow
  Driven Ontology

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Model Based Workflows

• Simple constructs for workflow specification
• Sequence
• Partial Order with sets
• Ex.
• Method 1
• Method3 ? Output
• Method 2
• MBW metamodel as an OWL ontology
• MBW generator software
• Extract MBW specifications automatically from
  domain knowledge represented in a WDO

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Current Status

• Developing and using WDO-Assistant prototype tool
  to create WDOs
• Collaborating with scientists to evaluate the
  tool
• Geophysics
• Seismology
• Environmental Sciences (Biology)
• Volcanology
• Developing MBW-Generator software to extract MBW
  specs from WDOs
• XML output
• Creating a graphical representation for it
• Considering producing MoML and using Keplers
  graphical representation
• Need to refine the workflow into an executable
  specification