• Journal of KIISE:Computing Practices and Letters
• /
• v.10 no.5
• /
• pp.394-405
• /
• 2004

To make Web Services the real applications, the efficient mechanisms for Web Services discovery, Web Services composition and Web Services execution must be provided. Among these issues, especially, Web Services composition plays the key roles in Web Services applications that are loosely coupled and composed applications consisted of primitive Web Service components. In this paper we demonstrate a new Web Service composition approach using ontologies. We apply ontologies to describe Web Services information such as Web Services input/output parameters, pre conditions, post conditions and other necessary management information. In this paper, we also introduce Action ontology and Object ontology to describe the functional properties of Web Services These ontologies offer semantic description of Web Services functionalities beyond the limitation of the current WSDL. We can achieve semantic interoperabilities between heterogeneous Web Services in terms of conceptual processing and realize semantic services composition. We implement semantic Web Services composition system called Genie based on service description ontologies.

• Journal of Internet Computing and Services
• /
• v.12 no.4
• /
• pp.119-133
• /
• 2011

With the advent of Web 2.0, the use of RESTful web services is expected to overtake that of the traditional SOAP-based web services. Recently, the growing number of RESTful web services available on the web raises the challenging issue of how to locate the desired web services. However, the existing keyword searching method is insufficient for the bad recall and the bad precision. In this paper, we propose a novel building semantic ontology method which employs both the clustering technique based on association rules and the semantic analysis technique based on patterns. From this method, we can generate ontologies automatically, reduce the burden of semantic annotations, and support more efficient web services search. We ran our experiments on the subset of 168 RESTful web services downloaded from the PregrammableWeb site. The experimental results show that our method achieves up to 35% improvement for recall performance, and up to 18% for precision performance compared to the existing keyword searching method.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.11
• /
• pp.21-30
• /
• 2009

Semantic web uses ontology languages such as RDF, RDFS, and OWL to define the metadata on the web. There have been many researching efforts in the semantic web technologies based on an agent for extracting triple and relation about concept of ontology. But the extraction of relation and triple about the concept of ontology based on an agent ends up writing a limited query statement as characteristics of an agent. As for this, there is the less of flexibility when extracting triple and relation about the other concept of ontology. We are need a query tool for flexible information retrieval of ontology that is can access the standard ontology and can be used standard query language. In this paper, we propose a SPARQL query tool that is can access the OWL ontology via HTTP protocol and it can be used to make a query. Query result can be output to the soap message. These operations can be support the web service.

• Journal of Internet Computing and Services
• /
• v.13 no.3
• /
• pp.115-126
• /
• 2012

Mashups have become very popular over the last few years, and their use also varies for IT convergency services. In spite of their popularity, there are several challenging issues when combining Open APIs into mashups, First, since portal sites may have a large number of APIs available for mashups, manually searching and finding compatible APIs can be a tedious and time-consuming task. Second, none of the existing portal sites provides a way to leverage semantic techniques that have been developed to assist users in locating and integrating APIs like those seen in traditional SOAP-based web services. Third, although suitable APIs have been discovered, the integration of these APIs is required for in-depth programming knowledge. To solve these issues, we first show that existing techniques and algorithms used for finding and matching SOAP-based web services can be reused, with only minor changes. Next, we show how the characteristics of APIs can be syntactically defined and semantically described, and how to use the syntactic and semantic descriptions to aid the easy discovery and composition of Open APIs. Finally, we propose a goal-directed interactive approach for the dynamic composition of APIs, where the final mashup is gradually generated by a forward chaining of APIs. At each step, a new API is added to the composition.

• Journal of Korea Spatial Information System Society
• /
• v.12 no.1
• /
• pp.100-104
• /
• 2010

Recently with advent of Web 2.0, RESTful Web Services are becoming increasing trend to emphasize Web as platform. There are already many services and the number of service increases in very fast pace. So it is difficult to find the service what we want by keyword based search. To solve this problem, we developed the search method using sem antic technologies about RESTful Web Services. For that, first we define the system structure and model the description format based on the integrated search system for OpenAPIs, and then we add Semantic Markup (tagging, semantic annotation) on the HTML description pages. Next we extract RDF document from them and store it in service repository. Based on the keywords that are extended by means of ontology, the developed system provides more purified and extended results than similarity-based keyword searching system.

• KIPS Transactions on Software and Data Engineering
• /
• v.2 no.5
• /
• pp.359-368
• /
• 2013

Mashup is a web application that combines several different sources to create new services using Open APIs(Application Program Interfaces). Although the mashup has become very popular over the last few years, there are several challenging issues when combining a large number of APIs into the mashup, especially when composite APIs are manually integrated by mashup developers. This paper proposes a novel algorithm for automatic Open API composition. The proposed algorithm consists of constructing an operation connecting graph and searching composition candidates. We construct an operation connecting graph which is based on the semantic similarity between the inputs and the outputs of Open APIs. We generate directed acyclic graphs (DAGs) that can produce the output satisfying the desired goal. In order to produce the DAGs efficiently, we rapidly filter out APIs that are not useful for the composition. The algorithm is evaluated using a collection of REST and SOAP APIs extracted from ProgrammableWeb.com.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2013.11a
• /
• pp.1612-1615
• /
• 2013

웹 2.0의 등장과 함께 Restful 웹 서비스의 활용이 전통적인 SOAP 기반 웹 서비스에 비해 크게 증가되었다. 최근 웹상에 이용 가능한 Restful 웹 서비스들의 수가 급격하게 증가됨에 따라 사용자들이 적합한 웹 서비스를 찾는 것은 매우 중요한 이슈로 대두되었다. 그러나 기존의 키워드 기반 검색 방법은 낮은 검색의 정확도 때문에 문제가 많다. 따라서 본 논문에서는 Restful 기반 온톨로지 구축 방법을 제안하고자 한다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2008.05a
• /
• pp.393-396
• /
• 2008

웹 서비스는 XML, SOAP, WSDL, UDDI, BPEL 등의 표준을 기본 구조로 하고 있으며 이러한 기술들은 SOA에서 요구되는 이기종 분산 플랫폼 상의 복잡한 애플리케이션 통합 문제를 유연하게 해결할 수 있는 다양한 인터페이스를 제공하고 있다. 본 논문에서는 SOA의 핵심 기술인 반자동 웹 서비스 조합 기법을 구현하기 위해 WS-BPEL 기법과 OWL-S 기법을 융합한 새로운 SemanticBPEL 조합 기법을 제안한다. 이 기법은 실험 분석을 통해 기존의 검색 방법보다 성능이 우수함을 보인다.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.7 no.3
• /
• pp.11-23
• /
• 2011

Recently, Open APIs are getting attention with the advent of Web 2.0. Open APIs are used to combine services and generate new services by Mashup. However, the growing number of available Open APIs raises a challenging issue how to locate the desired APIs. We automatically build ontologies from WSDL, WADL, HTML, and their underlying semantics. The key ingredient of our method is a technique that clusters input/output parameters in the collection of API methods into semantically meaningful concepts, and captures the hierarchical relationships between the terms contained in a parameter. These semantic ontologies allow search engines to support a similarity search for Open APIs based on various protocols such as SOAP, REST, JavaScript, and XML-RPC, and significantly improve the quality of APIs matching by the clustering and hierarchical relationships mechanism.

• Journal of KIISE:Software and Applications
• /
• v.36 no.3
• /
• pp.187-199
• /
• 2009

With the advent of Web 2.0, OpenAPIs are becoming an increasing trend to emphasize Web as platform recently. OpenAPIs are used to combine services and generate new services by mashup. However because the standard documents for OpenAPIs do not exist, it may restrict the use of OpenAPIs. Previous studies of OpenAPIs mashup have been limited to tool design or language definition for service combination rather than dynamic composition. On the other hand, Web services that are a software technology implementing SOA provide standard documents such as WSDL to explain each service, UDDI to register it, and SOAP to transfer messages. Thus Web applications can interpret and execute services by using these technologies. Recent works have also been performed to provide semantic features and dynamic composition for SOA. If a dynamic and systematic approach is provided to combine Web services and OpenAPIs, Web applications can provide users with diverse services. In this study, we present a SOA based framework for mashup of OpenAPIs and Web services. The framework supports dynamic composition of OpenAPIs and Web services, where the process of composite services is described in OWL-S. A prototype is provided to validate our framework. The framework is expected to add diversity to typical Web services.