Soon-Ja Kim

Framework for collaborative knowledge sharing and recommendation based on taxonomic partial reputations

We propose a novel system for collaborative knowledge sharing and recommendation based on taxonomic partial reputations on web-based personal knowledge directories. And we developed a prototype of the proposed system as a web-based user interface for personal knowledge management. This system presents a personal knowledge directory to a registered user. Such a directory has a personal ontology to integrate and classify the knowledge collected by a user from the Web. And the knowledge sharing activities among registered users generate partial reputation factors of knowledge items, their domain nodes, users and groups. Then new users can obtain the knowledge items proper to their needs, by referring such reputation values of those elements. In addition, users can also take the stem that is a set of common knowledge items over the domains designated by them. Thus proposed system can prevent cold-start problem because our knowledge recommendation mechanisms depend on the results of the collaborative knowledge sharing activities among users.

Secure password authentication for keystroke dynamics

Keystroke dynamics is an intelligent data processing technique of analyzing the users habitual typing patterns to identify him. Keystroke dynamics combined with password authentication has been widely used as a means to enhance user authentication system. However, the user authentication systems security does not rely solely on the keystroke dynamics. To guarantee a high level of security, more secure password authentication is needed. The design and development of a secure password authentication protocol for keystroke dynamics is discussed in this paper. We propose a new efficient password authentication protocol that is secure against all types of attacks considered in the paper. We also show that our two-party protocol is extended to a three-party protocol, where each user only shares a password with a trusted server. As a result, our protocols with keystroke dynamics can provide a secure and intelligent means of authentication and access control of computer users.

Framework for Personalized e-Mediator

As web-based mediation has been required to be more intelligent, some mediation services are providing discriminated information to customers according to their particular needs. However, such services often produce quite different results for a particular user in the scope and accuracy, since they use different policies and technologies for personalization. Accordingly, we propose a framework for a personalized mediator that provides a brokering service based on XML-based e-catalogs and XML/RDF schema to integrate the e-mediation. The framework creates specific metadata on every resource on the web including the information on some relations between one and other relevant elements. Then, it provides personalized information to users for product brokering using a filtering scheme based on the profiles of users and their characteristic groups.

Construction of Sequences for Multi-group FH-FDMA in DRT System

This paper presents a method of constructing frequency hopping sequences for military satellite communication system which employs frequency dehop-rehop transponder(DRT). In DRT system, the dehopping and rehopping is to be performed upon a group based approach where each group has its own hopping sequence and is characterized by synchronous connection-oriented(SCO) link. The hopping patterns generated through proposed method have optimal Hamming auto-correlation property according to Lempel-Greenberger bound and assure perfect orthogonality between hopping groups i.e. no chip collisions during the period. A practical implementation of the proposed method using shift registers is also described.