Community Computing - Advanced Design Approaches to Emerging Software Systems - page 203

scription, available message types are confined to
those of FIPA (Foundation for Intelligent Physical
Agents) (FIPA, 2000). In the Society description,
object types in a physical space are modeled as
member types. In the member type description,
the hierarchy of member types is described us-
ing the extends keyword as well as attributes and
actions which a member type has. For example,
'Streetlamp extends Electronic Appliance' would
mean that the 'Streetlamp' member type is a child
type of the 'Electronic Appliance' member type,
and thus 'Streetlamp' type inherits all attributes
and actions from 'Electronic Appliance' type.
An example CIM-PI based on the CHILD-
CARE scenario (See Section 6: Implementation)
is shown in Table 2. The 'Ghodam city' society
has two communities, 'Home' and 'Childcare'.
The 'Childcare' community consists of four roles:
'Child,' 'Family,' 'Neighbor,' and 'Observer,' and
has a goal named 'take_a_child_home.' If the goal,
'take_a_child_home,' is detected, then an instance
of 'Childcare' community is created by gathering
suitable members for each role. The candidate
member types who can take a role are presented
in the description of role-member type mapping.
For example, in the 'Childcare' community de-
scription, the 'Observer' role can be performed
by three member types: 'Camcorder,' 'Camera,'
and 'Streetlamp.' Among agents who are involved
in those member types, we should choose proper
members by using the cast description. Look at the
'Observer' role of 'Childcare' community for an
instance. The members who will take the role of
'Observer' should satisfy two conditions as fol-
lows. Its monitoring service should be available,
and it should be close to a missing child. In the role
description, we are able to know the cardinality
constraint of each role also. For the 'Observer'
role, we can assign one member at the minimum
and two members at the maximum.
CIM-PS . This model combines the simple
community computing model CIM-PI with the
details that specify how that system uses a par-
ticular platform. Actually, it is a bunch of source

codes for a particular platform. Its cooperation
portion can be derived from CIM-PI. In section
6, you can see the CHILDCARE community
computing system implemented using the simple
community computing model in the JADE plat-
form.
Model Transformation . For developing a
system, we perform model transformation from
a high-level abstraction model to a low-level ab-
straction model representing the final implemen-
tation. According to the proposed development
process, a model transformation process starts to
build a CCM and then refines it until we obtain the
source codes. The first step of the model transfor-
mation is that of turning a CCM into a CIM-PI. In
the next step, a CIM-PI is converted to a CIM-PS
using the specification of a particular platform. A
CIM-PS is a collection of source codes that can
realize members, communities, and a society. Fi-
nally, source codes are embedded into the existing
smart objects in a space. After deployment, the
coding objects become members in a community
computing system, building up a Space.

Static Community Situation Based
Community Computing Model

In a simple community computing model, co-
operation among members is considered as a
predefined procedure and described as a sort
of pseudo program. To describe cooperation, a
designer should decide which tasks of which
members should be executed. However, in the
case of a huge and complex cooperation model,
it is not easy for a designer to lay out a whole
cooperation procedure immediately. Besides,
a cooperation model is necessary to design the
cooperation intuitively among members in a com-
munity computing system. Therefore we propose
the static community situation based model as an
improved version. The major differences from the
simple model are as follows: