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mooring systems, etc.) they usually have different
data representations for those objects according to
the needs of each application requiring from the
solution some support for multi-resolution
representation of the data. For example, in structural
and naval engineering the models usually have dense
polygonal meshes, with a few objects representing
the outline of the artifacts, suitable for static and
dynamic stability studies with numerical methods. In
CAD/CAE the models usually have objects with
coarse grid meshes suitable for good visual
representation, but the problem is that all objects that
comprise the artifact should be represented yielding
huge models. For real time visualization those
models are almost intractable and, even today,
represents a great challenge for computer
graphics.due
3.1 CEE Requirements
Based on previous works in the related areas and on
an analysis of the domain of our scenario, we define
a set of requirements for our CEE.
Communication support - CEE should provide
different communication support possibilities:
synchronous, asynchronous, and enabled in various
media types. These supports should be provided in a
seamless way, so that users can start a
communication of one or of another type while they
are interacting with the CEE, or they should be able
to plan certain time for a specific communication
interaction. The communication support should be
integrated to the other tools in the CEE and provide
means of recording conversation and retrieving old
ones. This requirement helps user solve their
project’s problems in critical situation, with fast
interaction and negotiation, and it allows the
recovery of useful pieces of communication used to
solve similar problems in the past.
Coordination support – at the project
management level, multiple and different visions of
the on-going project must be provided. Users have
different background and need different types of
information to execute their duties. Project
management should also be feasible in a CEE.
Cooperation and flexibility support – there should
be process model flexibility support, like dynamic
change of process instances during run-time to
support dynamically evolving processes, possibility
of executing rollback of processes (reset, redo, undo,
recover, ignore, etc) and reuse of process fragments.
The cooperation support must provide different
levels of data access: local and distributed, shared,
public and private access, versioning control of
engineering models and related data, concurrency
control and synchronization. It is also necessary to
provide support for different types of data
interchange, concurrent work on shared copies,
change propagation. Different types of visualization
should also be available at the CEE, like real-time
simulation and visualization of 3D models;
walkthroughs in the managed models; object
interaction and manipulation; edition and planning
and lately, access to organizational work history.
Awareness – in our scenario the most important
types of awareness are: event monitoring – to
observe what is going on in all separate parts and
provide active notification to the right person, at the
right time and the right sub-system; workspace
awareness in the VE – to provide control of
collaborative interaction and changing of the user
location; mutual awareness – to allow users see each
other’s identity and observe each other’s actions;
group awareness – to facilitate the perception of
groups of interest connecting people who need to
collaborate more intensely.
Integration Management Infrastructure – at this
level, several services should be available in order to
guarantee the data and modeling persistency, and the
different levels of access control to different user
roles in our scenario. Here we include the shared
workspace and results service, access control
service, user management service, data
synchronization service and security service.
CVE specific requirements – high performance
and scalability to support execution of large shared
virtual worlds, which varies widely in size and
number of participants, over long periods of time; a
persistence mechanism to save and restore world
state between activations; version-safe updating
mechanisms, because large and long-lived virtual
worlds tend to incorporate different versions of the
same components; composability, so that one may
easily and effectively combine worlds and world
components developed by different organizations;
dynamic extensibility, the architecture must permit
the seamless run time extension and replacement of
any part of its hosted application.
4 PROPOSED SOLUTION
Our CEE has component based architecture (Figure
1) to facilitate the reuse of elements. The
architecture of the CEE uses a WfMS as its kernel
while the MMCS, CVE and the other components are
seamlessly accessed according to the collaborative
necessities of the team workers.
The integration of the WfMS with other
components is done in a seamless way through the
Collaboration Bus (CBus) in a way that the user
always interacts with the same interface independent
A MULTIMEDIA WORKFLOW-BASED COLLABORATIVE ENGINEERING ENVIRONMENT: INTEGRATING AN
ADAPTATIVE WORKFLOW WITH A MULTIMEDIA COLLABORATION SYSTEM AND A COLLABORATIVE
VIRTUAL ENVIRONMENT FOR PETROLEUM ENGENEERING
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