Global Positioning System Reference
In-Depth Information
user interface. The tool is able to capture every user-made modifi cation on
the workfl ow in form of provenance data. As a result the user is able to
trace back to previous versions of the same workfl ow. A VisTrails workfl ow,
both the set of operations and provenance data, is serialized in XML which
is saved in a VisTrails Repository. Execution is controlled by the VisTrails
Cache Manager, the VisTrails Log keeps a log of each workfl ow execution,
and the VisTrails Player invokes the appropriate functions from the
visualization libraries within VisTrails.
Business Workfl ow Languages
Scientifi c workfl ows and business workfl ows share the term workfl ow,
understood as an array of tasks to manage a certain process (Deelman et
al. 2009). In principle, both types of workfl ows share a lot of commonalities
such as modularity, encapsulation, and reuse of tasks. Differences, however,
come in practical terms. For instance, Barga and Gannon (2007) stated that
entire or part of scientifi c workfl ows are often constructed by scientists
themselves, who often are not technologically as skilled as software
engineers who are behind business workfl ows. As commented earlier,
scientifi c workfl ows are typically data-centric and datafl ow-oriented, as
opposed to task-centric and control-fl ow oriented as defi ning characteristics
of business workfl ows (Ludäscher and Goble 2005). These differences
suggest that scientifi c workfl ows are more dynamic in nature because they
refl ect evolving scientifi c needs in terms of large data sets, which require
robust and sophisticated scientifi c workfl ow systems (Section “Scientifi c
Workfl ow Systems”).
Having said this, while scientifi c workfl ows were the focus in the previous
section, in this section we treat business workfl ows that are materialized by
means of business workfl ows languages (BWL). Note that we use the term
BWL throughout the chapter only for grouping descriptive languages for
modeling business workfl ows. Interested readers may fi nd a comprehensive
survey on business workfl ows standards in Mili et al. (2010).
Business Process Model and Notation
The Object Management Group (OMG) recently released version 2 of the
Business Process Model and Notation 11 (BPMN) (OMG 2011) that standardizes
a set of graphical symbols with well-defi ned semantics (e.g., task, data input,
parallel fl ow, etc.) to visually specify abstract processes. By abstract we refer
to a set of high-level tasks, procedures and steps to achieve a business goal
or process, avoiding at this stage technical and implementation details.
11 http://www.bpmn.org
Search WWH ::




Custom Search