Kyong-Ho Lee

The State of the Art and Practice in Digital Preservation

The goal of digital preservation is to ensure long-term access to digitally stored information. In this paper, we present a survey of techniques used in digital preservation. We also introduce representative digital preservation projects and case studies that provide insight into the advantages and disadvantages of different preservation strategies. Finally, the pros and cons of current strategies, critical issues for digital preservation, and future directions are discussed.

Geometric structure analysis of document images: a knowledge-based approach

This paper presents a knowledge-based method for sophisticated geometric structure analysis of technical journal pages. The proposed knowledge base encodes geometric characteristics that are not only common in technical journals but also publication-specific in the form of rules. The method takes the hybrid of top-down and bottom-up techniques and consists of two phases: region segmentation and identification. Generally, the result of the segmentation process does not have a one-to-one matching with composite layout components. Therefore, the proposed method identifies non-text objects, such as images, drawings, and tables, as well as text objects, by splitting or grouping segmented regions into composite layout components. Experimental results with 372 images scanned from the IEEE Transactions on Pattern Analysis and Machine Intelligence show that the proposed method has performed geometric structure analysis successfully on more than 99 percent of the test images.

An efficient algorithm to compute differences between structured documents

SGML/XML are having a profound impact on data modeling and processing. We present an efficient algorithm to compute differences between old and new versions of an SGML/XML document. The difference between the two versions can be considered to be an edit script that transforms one document tree into another. The proposed algorithm is based on a hybridization of bottom-up and top-down methods: The matching relationships between nodes in the two versions are produced in a bottom-up manner and then the top-down breadth-first search computes an edit script. Faster matching is achieved because the algorithm does not need to investigate the possible existence of matchings for all nodes. Furthermore, it can detect structurally meaningful changes such as the movement and copy of a subtree as well as simple changes to the node itself like insertion, deletion, and update.

Constructing composite web services from natural language requests

As a demand on composite Web services increases, there is a growing interest in a convenient access to them. This paper proposes a natural language interface to Web services, which can be used even by a novice user who does not know Web service technologies. Given a users natural language request to a composite service, the proposed method generates an abstract workflow, which describes the constituent tasks and their transitions in a composite service. Specifically, the proposed method constructs a sophisticated abstract workflow from complex sentences with phrases and control constructs. Experimental results with a variety of natural language requests show that the proposed method successfully extracts abstract workflows, resulting in an accuracy of 95.2%.

A Model-Driven Approach for Describing Semantic Web Services: From UML to OWL-S

With the wide spread of Web services, there is a growing interest in semantic Web services based on ontologies, which support the automated discovery, selection, and composition of Web services. OWL-S is a de facto standard ontology for describing the semantics of Web services. Due to the complexity of the OWL-S grammar, it is difficult to construct OWL-S descriptions manually. This paper presents an efficient model-driven approach to generate OWL-S ontologies from Unified Modeling Language (UML) models, which are widely used for software design and development. The proposed method is based on UML profiles to represent the characteristics of OWL-S. Specifically, a domain ontology is transformed into a class diagram, and UML diagrams are extended to represent the behavior of business processes. Finally, an XML metadata interchange (XMI) file extracted from UML diagrams is transformed into an OWL-S representation via an extensible stylesheet language transformation (XSLT) script. Experimental results with a large number of UML diagrams show that the proposed method handles effectively the control flow of complex processes.

Development of a standard format for eBooks

Since an electronic book (eBook) has various advantages over a paper-based book, there is a growing interest in eBooks. EBook industries are using different document formats creating difficulties in the interoperability and interchangeability of eBooks. The U.S. and Japan have realized the importance of a standard format for eBooks and developed such standards. Recently, Korea has also developed a standard format based on XML. The primary goal of this standard is to support the interchangeability of eBooks, reflect the characteristics of the Korean publication environment, simplify the creation process, and promote compatibility with other standards. It includes an extension mechanism for various document classes, and supports advanced style control such as vertical writing and multi-column based on XSL.

Standardization aspects of eBook content formats

This paper presents the necessity and direction of a standard for representing contents of electronic books (eBooks). To identify the current problems of content formats, as a case study, we discuss the advantages and disadvantages of the Open eBook Publication Structure (OEBPS) and Portable Document Format (PDF) in terms of functional aspects as well as critical standardization issues such as interoperability, openness, applicability, and extensibility. Particularly, this paper suggests an Extensible Markup Language (XML)-based improvement of the OEB format as a standard. This paper also describes that PDF can be used together for different aspects of publishing process.

Fast Quality Driven Selection of Composite Web Services

The composite Web service selection is the process of building an executable composite Web service. Generally, the selection process involves decision making in terms of non-functional properties of Web services such as QoS requirements. Since the number of Web services is rapidly increasing and the QoS of the Web services environment changes dynamically, the fast selection is important. This paper presents a fast method for quality driven composite Web services selection based on a workflow partition strategy. The proposed method partitions an abstract workflow into two sub-workflows to decrease the number of candidate services that should be considered. A mixed integer linear programming is utilized for solving the service selection problem. Experimental results show that the partition strategy performed faster than the optimal strategy. Also, the qualities of the selected composite Web services are not significantly different from the optimal one

A Light-weight Framework for Hosting Web Services on Mobile Devices

In the ubiquitous era, for Web services to become a universal communication paradigm, mobile devices enabled with Web services should be considered as an equal participant of the service-oriented architecture. Here, mobile devices play the role of clients, providers, or even brokers. To establish a distributed application framework on a P2P network environment, this paper presents a light-weight framework for hosting Web services on mobile devices. The proposed framework contains several built-in functionalities such as the processing of SOAP messages, the execution and migration of services, the management of context and service directory, and the publishing and discovery of services. To evaluate the performance of the proposed mobile Web service framework, a real-world scenario has been tested on physical devices connected by Bluetooth.

Semantic description, discovery and integration for the Internet of Things

To share and publish the domain knowledge of IoT objects, the development of a semantic IoT model based directory system that manages meta-data and relationships of IoT objects is required. Many researches focus on static relationships between IoT objects. However, because complex relationships between various resources change with time in an IoT environment, an efficient method for updating the meta-data is required. Thus, we propose an IoT-DS as the IoT directory that supports semantic description, discovery, and integration of IoT objects. Firstly, we introduce a semantic IoT component model to establish a shared conceptualization. Secondly, we present general cases of relationships to efficiently interact between IoT-DS and IoT objects. Thirdly, we construct IoT-DS as a Web portal. Finally, we verify in our evaluation study that the query processing time and communication workload imposed by the proposed approach are reduced.