consist of describing the model using a formal
language. In the case of this project the language
chosen was Web Ontology Language (OWL)
generated by Protégé. During the formalization and
implementation stages the ontology model can be
submitted for validation by experts as well as be
used by others sub-projects members in order to
provide immediate feedback. The implementation
stage may also include the construction of libraries
or reusable softwares which aims to use the model
so that usability, performance and portability can be
measured beforehand.
The METHONTOLOGY development cycle is
concluded with the maintenance stage which
includes the validation and the delivery of the model
for the scientific community. One may understand
this phase as a beta test of the ontology model.
3.3.2 METHONTOLOGY: Building the 3D
Graphic Model
The first multimedia model incorporated to our
unified ontology model was the 3D graphic model.
This model was chosen due to the importance of
representing the anatomical parts in a more
appealing manner, including the possibility of
interaction and animation directly performed on the
3D structure (for simulation purpose) and also
because the 3D modeling brought to us some
challenges to overcome in order to represent the
anatomic parts in a more realistic way.
Some of the challenges we had to overcome can
be summarized as follows: (a) the lack of a specific
3D modeling methodology, (b) the divergences
found among different anatomical atlases used as
reference, (c) the difficulty of setting standards for
the 3D modeling such as the size of the 3D objects,
proportionality of the model compared with a real
breast, color and texture issues and grouping and/or
linkage of the 3D objects to the ontology model.
The lack of a 3D modeling methodology was
solved by adapting the METHONTOLOGY process
to the 3D modeling tasks. This way we could
provide a better interaction between the ontology
team and the 3D modeling team which resulted in a
better validation process since the graphical artifacts
was frequently used to check the comprehension of a
concept described by the ontology model. The
divergences among the references were solved by
using the opinion of the experts and scientific
community whom were in participation of the
ontology model construction. Finally, the need of
setting standards were addressed in the beginning of
the 3D modeling process so that all the people
involved already new and understood our goals and
limitations for modeling the female breast in a more
fidelity and truthiness manner.
In conclusion, we decided to keep and adapt the
METHONTOLOGY as the working methodology
for the 3D modeling tasks.
From this, the first step of 3D modeling
consisted of planning the work. During the planning
the following tasks were executed: a) study of the
METHONTOLOGY; b) structuring of
METHONTOLOGY stages to the 3D modeling
needs; c) production of schedule; d) initial
preparation of requirements.
Next the planning phase, the stages of
METHONTOLOGY were applied directly to the 3D
modeling tasks with some adaptations.
In the Specification stage the 3D team worked
closely to the ontology team by gathering the
requirements of the model from the experts.
Consequently, the use of knowledge acquisition
(KA) techniques is imperative at this point as
defined in Brasil L. M (1994). Some of the KA
techniques applied in this project are: a) dynamic
reading of documents; b) observations; c)
interviews; d) definition of protocols.
In the Conceptualization stage the 3D team
provided support to the ontology team by initially
prototyping visual presentations of the concepts as
well as by validating such concepts with the experts
in mastology. It is also part of the work to define the
technique to be applied in the final version of the 3D
modeling. Regarding to this, the method of polygons
has proved effective due to its compatibility with
complementary techniques such as edge loops and
face projection which improved our results.
The Formalization and Implementation stages of
METHONTOLOGY represent the construction of
the 3D model for an anatomic structure as well as
the connection of such graphical object to the
ontology. At this stage, the 3D modeling team may
also need to compare graphical models constructed
by using different techniques which improves the
accuracy of the work.
It is important to point out that due to modeling
easiness and the already acquired knowledge of our
3D modeling team we have opted for using Maya
Software 2010. Maya has a system of particles and
fluids and the facility of texturization, composition,
renderization and animation which have proved to
be handy in our project. Besides, this software is
widely used in the biomedical area and was the
object of study in Gu S. (2006) and Sharpe J.,
Lumsden C. J. and Woolridge N. (2008) whom
presented it as an accessible alternative to capture
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