Through computation with words and the use of
linguistic variables, the solutions need to manage the
inherent fuzziness in human queries, representation
of concepts and coordination, properly and
efficiently.
To address the lack of flexibility in representing
documents and queries, fuzzy systems that deal with
this type of problem for individual users have also
been studied and developed by several researchers.
In such approaches, a fuzzy set will represent each
keyword. The membership value of each piece of
information or document indicates its degree of
relevance to the fuzzy set denoted by the keyword.
In this way, it is easy to use linguistic qualifiers for
computing with words to help the information
retrieval process. While this can help in indexing
and the querying process, users can also employ it to
provide feedback information. Such information can
be used to evaluate the retrieval system and in turn
for evaluation of the awareness agent.
A scheme that is based on fuzzy proximity
networks in line with the work reported in (Shenoi,
1989) can be utilized to build the required intelligent
system. The network is capable of providing
coordination services for cooperating agents. It can
also conveniently take the technicians’ awareness
levels and profiles into account while processing
their queries. The coordinator role and its agent can
evaluate and aggregate the queries from individual
agents to help the cooperating agents in achieving
their common goal. One important aspect of such
coordination relates to connecting the cooperating
agents by pointing information and documents
relevant to their task, even when one agent has not
asked for them. To achieve this, the system needs to
be able to process queries from different cooperating
users as collaborative queries. In this case, each
node i of the fuzzy proximity network represents a
keyword. The weight w(i, j) represents the fuzzy
relevance of the two keywords at nodes i and j. Such
a scheme does emphasize the keyword structures
and connections, rather than focusing on the
keywords themselves. The relevance between the
keywords is based on the co-occurrence of a
keyword or the so-called Miyamoto’s measure,
similar to what is reported in (Miyamoto, 1983).
Stated simply, this measure implies that the more
often two keywords occur simultaneously, the higher
is their relevance to one another.
Consider a fuzzy proximity scheme, partially
shown in Figure1. Here, as in any case of practical
importance, the pieces of information are in several
documents, including a document d denoted by D
(d), where the k
th
keyword in d is represented by
K(d, k). The keywords within any given document
are considered to be related to each other. For
instance, keywords K (1, 1), K (1, 2), … K (1, m) are
considered to be related, as they appear within the
same document, D (1). The fuzzy relevance of
keywords is represented by the weight w between
their respective nodes. For example, here the fuzzy
relevance between the two keywords K (1, 1) and K
(1, 2) is represented by the weight w (K (1, 1), K (1,
2)). In accordance with the co-occurrence concepts,
if document D (1) refers to another piece of
information in D (2) or is referred to by the
information content of D (3), then the keywords K
(2, 1), K (2, 2), … K (2, n) as well as the keywords K
(3, 1), K (3, 2), … K (3, p) are also considered to be
related to each other, although in a weaker sense.
This type of information will establish the initial
setting of weights in the network model. Obviously,
after this initial stage, the weights can be updated
through adaptive mechanisms and supervised
learning.
For each document, its characterizing attributes
are calculated based on a maximum spanning tree,
see (Sun, 1990). Here, as in several other
applications, a spanning tree is the tree that covers a
given set of nodes, i.e. keywords. The weight of the
tree W (.), is the sum of the weights of the branches
in that tree. A maximum spanning tree is established
as the tree with the maximum weight for a particular
set of nodes. Given a query Q (q), its maximum
spanning tree weight W (Q), is used as the
characterizing measure of the query. The weight of
the maximum spanning tree for the keywords
common between Q (q) and a document D (d)
divided by W (Q) is used to represent the
characterizing attribute measure R (.), of document
D (d) with regard to Q (q). These characterizing
attributes calculated for all of the documents, are
then used for ranking the documents with regard to
their relevance to the query Q (q).
In summary, each human role in a cooperative
management environment is supported by a software
agent that assists the process to collaboration by
helping realize the right level of awareness at the
right time for each collaborating role. Although
conceptually one could use many different
paradigms of artificial intelligence (e.g., case based
reasoning, model-based reasoning, fuzzy logic etc),
this paper discusses the design of an awareness
agent based on fuzzy logic. It is possible to use a
number of ways to involve fuzzy logic in the design
of such systems, as discussed in (Shahrestani, 2005).
Here, the Fuzzy Proximity Network (FPN) has
provided us with a simple example that illustrates
IMPROVING COOPERATIVE MANAGEMENT - Fuzzy Modeling and Proximity Networks
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