• Journal of Korean Society of Transportation
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• v.34 no.5
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• pp.437-448
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• 2016

Some previous researches suggested a transit trip destination inference method by constructing trip chains with incomplete(missing destination) smart card dataset obtained on the entry fare control systems. To explore the feasibility of the transit trip destination inference method, the transit trip chains are constructed from the pre-paid smart card tagging data collected in Busan on October 2014 weekdays by tracing the card IDs, tagging times(boarding, alighting, transfer), and the trip linking distances between two consecutive transit trips in a daily sequences. Assuming that most trips in the transit trip chains are linked successively, the individual transit trip destination zones are inferred as the consecutive linking trip's origin zones. Applying the model to the complete trips with observed OD reveals that about 82% of the inferred trip destinations are the same as those of the observed trip destinations and the inference error defined as the difference in distance between the inferred and observed alighting stops is minimized when the trip linking distance is less than or equal to 0.5km. When applying the model to the incomplete trips with missing destinations, the overall destination missing rate decreases from 71.40% to 21.74% and approximately 77% of the destination missing trips are the single transit trips for which the destinations can not be inferable. In addition, the model remarkably reduces the destination missing rate of the multiple incomplete transit trips from 69.56% to 6.27%. Spearman's rank correlation and Chi-squared goodness-of-fit tests showed that the ranks for transit trips of each zone are not significantly affected by the inferred trips, but the transit trip distributions only using small complete trips are significantly different from those using complete and inferred trips. Therefore, it is concluded that the model should be applicable to derive a realistic transit trip patterns in cities with the incomplete smart card data.

• Journal of applied mathematics & informatics
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• v.26 no.5_6
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• pp.1139-1147
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• 2008

A. Saxena et al. first proposed a two-flow blind identification protocol in 2005. But it has a weakness of the active-intruder attack and uses the pairing operation that causes slow implementation in smart cards. In this paper, we give a method of the active-intruder attack on their identification scheme and propose a new zero- knowledge blind identification protocol for Smart cards. Our protocol consists of only two message flows and does not rely on any underlying signature or encryption scheme. The prover using computationally limited devices such as smart cards has no need of computing the bilinear pairings. It needs only for the verifier. Our protocol is secure assuming the hardness of the Discrete-Logarithm Problem in bilinear groups.

• The KIPS Transactions:PartD
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• v.10D no.6
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• pp.1033-1040
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• 2003

In order to provode information services on M-Commerce, a payment solution with security function should be required. User's mobile terminals for using M-Commerce services are diversifying to cellular phone, PDA, Smart phone etc. Among them, intergration of PDA's interface and mobile connection overcomes the weak point of existing cullular phone depending on information via the internet. In this paper, the protocol for a credit card transaction on PDA using ECC is presented. Secure Card module on this protocol encrypts user's information such as private information, delivery information and credit card information and store them on PDA in order to free from inputting information whenever it is used. This scheme also offers security services on M-Commerce including authentication, confidentiality, integration, non-repudiation and so on.

• Electronics and Telecommunications Trends
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• v.17 no.3 s.75
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• pp.15-22
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• 2002

본 고에서는 현재 개인용 보안장치로 가장 널리 사용되고 있는 스마트카드를 이용한 휴대단말기의 보안기술 동향에 대한 분석으로써, WAP 포럼에서의 WIM과 3GPP에서 논의되고 있는 USIM에 대한 기술과 향후 전망에 대해 기술하고자 한다.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.35-36
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• 2006

This paper presents an effective multiplier in GF($2^m$) based on programmable cellular automata (PCA) and uses a normal basis. The proposed architecture has the advantage of high regularity and a reduced latency. The proposed architecture can be used in the effectual hardware design of exponentiation, division, inversion architectures.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 1995.11a
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• pp.314-322
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• 1995

본 논문에서는 기존에 문태욱 등이 제안한 이동통신용 키분배 방식을 살펴보고, 이 세 가지 키분배 프로토콜의 문제점을 제기하며, 이를 해결할 수 있는 개선방안도 제시한다.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.54-54
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• 2004

• Proceedings of the Korean Information Science Society Conference
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• 2001.10a
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• pp.769-771
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• 2001

인터넷의 급속한 발달과 이를 통한 다양한 서비스가 확산됨에 따라, 인증과 보안은 아주 중요한 분야로 대두되고 있다. 본 논문에서는 Egterl 을 이용하여 최근 정보화 사회에서 개인적 정보 뿐만 아니라 비즈니스 간의 데이터 응용 분야에 이르기까지 폭 넓게 사용되어지고 있는 스마트 카드의 인증과 보안 시스템 대한 모델링 및 정형검증에 대해 논한다.

• Journal of the Chungcheong Mathematical Society
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• v.21 no.3
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• pp.403-411
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• 2008

In 2005, A. Saxena, B. Soh and S. Priymak [10] proposed a two-flow blind identification protocol. But it has a weakness of the active-intruder attack and uses the pairing operation that causes slow implementation in smart cards. In 2008, Y. W. Lee [9] made a method of the active-intruder attack on their identification scheme and proposed a new zero-knowledge blind identification protocol for smart cards. In this paper, we give more simple and fast protocols than above protocols such that the prover using computationally limited devices such as smart cards has no need of computing the bilinear pairings. Computing the bilinear pairings is needed only for the verifier and is secure assuming the hardness of the Discrete-Logarithm Problem (DLP).

• Journal of the Chungcheong Mathematical Society
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• v.20 no.4
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• pp.355-366
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• 2007

In this paper, we propose a new blind group identification protocol and a hidden group signature protocol as its application. These protocols involve many provers and one verifier such that (1) the statement of all the provers are proved simultaneously, (2) and also all the provers using computationally limited devices (e.g. smart cards) have no need of computing the bilinear pairings, (3) but only the verifier uses the bilinear pairings. A. Saxena et al. proposed a two-round blind (group) identification protocol in 2005 using the bilinear pairings. But it reveals weakness in the active-intruder attack, and all the provers as well as the verifier must have devices computing bilinear pairings. Comparing their results, our protocol is secure from the active-intruder attack and has more fit for smart cards. In particular, it is secure under only the assumption of the hardness of the Discrete-Logarithm Problem in bilinear groups.