Young-Do Joo

Multi-document Summarization Exploiting Semantic Analysis Based on Tag Cluster

Multi-document summarization techniques aim to reduce the documents into a small set of words or paragraphs that convey the main meaning of the original documents. Many approaches for multi-document summarization have used probability based methods and machine learning techniques to summarize multiple documents sharing a common topic at the same time. However, these techniques fail to semantically analyze proper nouns and newly-coined words because most of them depend on old-fashioned dictionary or thesaurus. To overcome these drawbacks, we propose a novel multi-document summarization technique which employs the tag cluster on Flickr, a kind of folksonomy systems, for detecting key sentences from multiple documents. We first create a word frequency table for analyzing the semantics and contribution of words by using HITS algorithm. Then, by exploiting tag clusters, we analyze the semantic relationship between words in the word frequency table. The experimental results on TAC 2008, 2009 data sets demonstrate the improvement of our proposed framework over existing summarization systems.

Security Enhancement of Biometrics-based Remote User Authentication Scheme Using Smart Cards

In 2011, Das proposed an effective biometrics-based remote user authentication scheme using smart cards that can provide strong authentication and mutual authentication, while eliminating the security drawbacks of Li-Hwang`s scheme. In this paper, we have shown that Das`s scheme is still insecure against several attacks and does not provide mutual authentication. Also, we proposed the enhanced scheme to overcome these security weaknesses, even if the secret information stored in the smart card is revealed. As a result of security analysis, the enhanced scheme is secure against user impersonation attack, server masquerading attack, off-line password guessing attack, and insider attack. And we can see that the enhanced scheme provides mutual authentication between the user and the server.

Security Improvements on Smart-Card Based Mutual Authentication Scheme

Abstract Password-based authentication schemes have been widely adopted in order to protect resources from unauthorized access. In 2008, Liu et al. proposed a new mutual authentication scheme using smart cards which can withstand the forged attack. In this paper, author has proven that Liu et al.s scheme is still vulnerable to the various attacks by analyzing the security of their scheme. This paper introduces an enhanced scheme to overcome these security weakness and to provide mutual authentication between the user and the server, even if the secrete information stored in the smart card is revealed by an attacker. The comparative result from the security analysis demonstrates that the proposed scheme is more secure against the possible attacks than Liu et al.s scheme. Key Words : Mutual Authentication, Smart Card, User Impersonation Attack, Password Guessing Attack * 정회원, 강남대학교 컴퓨터미디어정보공학부접수일자 2012년 9월 18일, 수정일자 2012년 11월 8일게재확정일자 : 2012년 12월 14일Received: 27 September 2012 / Revised: 24 November 2012 /Accepted: 14 December 2012

Analysis on Security Vulnerabilities of a Biometric-based User Authentication Scheme for Wireless Sensor Networks

The numerous improved schemes of remote user authentication based on password have been proposed in order to overcome the security weakness in user authentication process. Recently, some of biometric-based user authentication schemes to use personal biometric information have been introduced and they have shown the relatively higher security and the enhanced convenience as compared to traditional password-based schemes. These days wireless sensor network is a fundamental technology in face of the ubiquitous era. The wireless sensor networks to collect and process the data from sensor nodes in increasing high-tech applications require important security issues to prevent the data access from the unauthorized person. Accordingly, the research to apply to the user authentication to the wireless sensor networks has been under the progress. In 2010, Yuan et al. proposed a biometric-based user authentication scheme to be applicable for wireless sensor networks. Yuan et al. claimed that their scheme is effectively secure against the various security flaws including the stolen verifier attack. In this paper, author will prove that Yuan et al.`s scheme is still vulnerable to the password guessing attack, user impersonation attack and the replay attack, by analyzing their security weakness.

Implementation of Facility Maintenance Management System using Smart Phones

Recently, the demand for mobile systems is remarkably growing due to the explosive spread of smart phones. The mobile system based on the smart phones enables the real time communication and business process by utilizing the on-line information on the spot anytime and anywhere. This paper proposes a development model to use android-based mobile applications to be applicable to the facility defect maintenance management in apartment buildings. The proposed methodology aims to implement an incorporated system to bind the web-based system and the mobile system in systematic interaction in order to feasibly realize the concept of mobile office.

Intelligent System Modeling for Human Cognition

The development of computer-based modeling systems has allowed the operationalization of cognitive science issues. Human cognition has become one of the most interested areas in artificial intelligence to emulate high-level human capability. This paper introduces a methodology well-suited for designing of an intelligent system to evaluate human cognition. The research investigates how to elicit and represent cognitive knowledge from human being. Crucial to this research is to identify the collective perception to aggregate the congruence or sharing of individual psychological cognition. Unlike standard approaches based on the statistical techniques, the modeling presented employs a theory of fuzzy relation to deal with the required issues of similarity.

Analysis on Security Vulnerabilities of a Password-based User Authentication Scheme for Hierarchical Wireless Sensor Networks

The numerous improved schemes of user authentication based on password have been proposed in order to prevent the data access from the unauthorized person. The importance of user authentication has been remarkably growing in the expanding application areas of wireless sensor networks. Recently, emerging wireless sensor networks possesses a hierarchy among the nodes which are divided into cluster heads and sensor nodes. Such hierarchical wireless sensor networks have more operational advantages by reducing the energy consumption and traffic load. In 2012, Das et al. proposed a user authentication scheme to be applicable for the hierarchical wireless sensor networks. Das et al. claimed that their scheme is effectively secure against the various security flaws. In this paper, author will prove that Das et al.`s scheme is still vulnerable to man-in-the-middle attack, password guessing/change attack and does not support mutual authentication between the user and the cluster heads.

Security Enhancements of a Mutual Authentication Scheme Using Smart Cards

Password-based authentication schemes have been widely adopted to protect resources from unauthorized access. In 2008, Liu et al. proposed a new mutual authentication scheme using smart cards which can withstand the forgery attack. In this paper, we analyze the security of Liu et al.’s scheme, and we show that Liu et al.’s scheme is still vulnerable to the various attacks. Also, we propose the enhanced scheme to overcome these security weaknesses and provide mutual authentication between the user and the server, even if the secret information stored in the smart card is revealed by an attacker. As a result of security analysis, the enhanced scheme is more secure than Liu et al.’s scheme.

Design and Implementation of LBSNS Service Model

Recently, Location Based Service (LBS) is expanding its service areas with the spread of smart phones and is offering more personalized contents according to the variety of needs from customers. Specially, Location Based Social Network Service (LBSNS) is emerging as the most promising service among the applications of LBS. This paper proposes a LBSNS service model to form a community adaptively based on the location of user’s mobile devices. The methodology suitable for implementing the effective management and the automatic update of this social network community is presented in this paper. In addition, we describe the significance of the proposed model to promote future researches of LBSNS under the upcoming domination of mobile environment.

Cryptanalysis of nonce-based mutual authentication scheme using smart cards

Recently, many user authentication schemes using smart cards have been proposed to improve the security weaknesses in user authentication process. In 2008, Liu et al. proposed a new mutual authentication scheme using smart cards which is based on nonce and can withstand the existing of forged attack. In this paper, we analyze the security weaknesses of Liu et al.s scheme. Although Liu et al.s scheme overcame the vulnerability of Shen et al.s scheme, we have shown that Liu et al.s scheme is still insecure against the Impersonation attack and password guessing attack, and does not provide the mutual authentication between the user and the remote server.