
 
goal describes the required web service capability as 
input. Semantic discovery adds accuracy to the 
search results in comparison to traditional Web 
service discovery techniques, which are based on 
syntactical searches over keywords contained in the 
web service descriptions (U. Keller, Lara R., 
Polleres A, 2004).  
 Improvement in matching process could be 
gained by the use of ontological information in a 
useful form. With the use of this information, it can 
be possible to rate the services found in discovery 
process. As in real life, users/ agents should be able 
to define how they see the relation of ontological 
concepts from their own perspective. Similarity 
measures have been widely used in information 
systems (Voorhees, E, 1998, Ginsberg, A., 1993, 
Lee, J., M. Kim and Y. Lee, 1993), cognitive 
science, software engineering and AI (Agirre, E. and 
G. Rigau, 1996, Hovy, E., 1998, Wang, Y. and E. 
Stroulia, 2003). So integration of knowledge from 
these techniques can improve the matching process. 
By using semantic distance definition 
information, we aim to get a rated and ordered set of 
web services as the general result of the discovery 
process. We believe that this would be better than 
set-based classification of discovered services. In 
this paper, we propose a new scheme of 
matchmaking that aims to improve retrieval 
effectiveness of semantic matchmaking process. Our 
main argument is that conventional evaluation 
schemes do not fully capture the added value of 
service semantics and they do not consider the 
assigned degrees of match, which are supported by 
the majority of discovery engines. The existing 
approach to service matchmaking contains 
subsumption values regarding the concept that the 
service supports. In our proposed approach, we add 
semantic relatedness values onto existing 
subsumption-based procedures. We introduce value 
added approaches to matchmaking process such as 
property-level matching, semantic distance 
information and WordNet scoring. Property-level 
matching provides capturing similarity between 
concepts that do not have a subsumption relation. So 
that, services that would not be classified, are ranked 
with our matchmaking agent. Similarity distance 
provides user’s profile to be represented in the 
ontology. Similarity distance weights can be 
assigned on the links between concepts to specify 
concepts relatedness to each other in an explicit way. 
Also by making use of WordNet, we introduce a 
second source of semantic repository to be utilized 
in matchmaking. Our test results in section 5 
indicate that these value added approaches increases 
the captured semantic relations between parameters 
of services and provide a better ranking of services 
resulting in better user experience in matchmaking. 
2 RELATED WORK 
Semantic Web services aim to realize the vision of 
the Semantic Web, i.e. turning the Internet from an 
information repository for human consumption into 
a worldwide system for distributed Web computing 
(http://www.w3.org/2001/sw/, 2006.). The system is 
a machine-understandable media where all the data 
is combined with semantic metadata. The domain 
level formalizations of concepts form up the main 
element within this system, which is called ontology 
(http://www.w3.org/Submission/OWL-S, 2004).  
Ontology represents concepts and relations between 
the concepts; these can be hierarchical relations, 
whole-part relations, or any other meaningful type of 
linkage between the concepts(H. El-Ghalayini, M. 
Odeh, R. McClatchey, and T. Solomonides,, 2005).  
The semantic matchmaking process is based on 
ontology formalizations over domains. In the 
upcoming section we present some of the selective 
research on the matchmaking process considering 
the concepts that we build our research on. 
Matchmaking of Web services considers the 
relationship between two services. The first one is 
called the advertisement and the other is called the 
request (Klusch, M., Fries, B., Khalid, M., and 
Sycara, K.. 2005). Advertisement denotes the 
services description of the existing services while 
the request indicates the picture of service 
requirements (Wang, Y. and E. Stroulia, 2003).  
In (Wang, H., Zengzhi L., Fan L., 2006), the 
problem of capability matchmaking is analyzed with 
regarding to Web services, especially the 
Preconditions and Effects (PE) matchmaking. In the 
paper, the authors present a service similarity 
function that determines similar parameter classes 
by using a matching process over synonym sets, 
semantic neighbourhood, and distinguishing 
features. Parameter pairing is the process that is used 
for matching service descriptions. In the work, 
maximum weight bi-partite graph matching method 
is utilized for parameter finding; the weights of bi-
partite graph’s edges are evaluated with matching 
degree between function parameters calculated by 
the similarity function mentioned above.  
Although good results are obtained with the 
usage of this method, it should still be improved in 
two terms: One is that, it needs to be extended on 
pre-condition and affect because the matching is 
ENASE 2007 - International Conference on Evaluation on Novel Approaches to Software Engineering
96