• Journal of the Korean Mathematical Society
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• v.9 no.2
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• pp.75-84
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• 1972

• Korea Multimedia Society
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• v.5 no.3
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• pp.93-101
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• 2001

No Abstract (See Full-text)

• Proceedings of the Korea Water Resources Association Conference
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• 2003.05a
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• pp.3-3
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• 2003

No Abstract, See Full Text

• Management & Information Systems Review
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• v.7
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• pp.1-20
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• 2001

KORMARC used in library bibliographic information, had been pointed several weaknesses such as inflexibility lack of link information and compatibility. In addition, a sudden increase in digital information associated with development of internet is demanding an integration of web resources metadata as the resource of library information. This study mentioned XML/KORMARC system or adaption of XML standard format turned out to be the most efficient way to use KORMARC formats and to expand the range of those information service such as bibliographic information, factual information, referral information and full-text.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.8
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• pp.1946-1963
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• 2012

Hummingbird is a lightweight encryption and message authentication primitive published in RISC'09 and WLC'10. In FSE'11, Markku-Juhani O.Saarinen presented a differential divide-and-conquer method which has complexity upper bounded by $2^{64}$ operations and requires processing of few megabytes of chosen messages under two related nonces (IVs). The improved version, Hummingbird-2, was presented in RFIDSec 2011. Based on the idea of differential collision, this paper discovers some weaknesses of the round function WD16. Combining with the simple key loading algorithm, a related-key chosen-IV attack which can recover the full secret key is proposed. Under 15 pairs of related keys, the 128 bit initial key can be recovered, requiring $2^{27}$ chosen IV and the computational complexity is $O(2^{27})$. In average, the attack needs several minutes to recover the full 128-bit secret key on a PC. The experimental result corroborates our attack. The result shows that the Hummingbird-2 cipher can't resist related key attack.

• Journal of Communications and Networks
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• v.6 no.1
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• pp.46-59
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• 2004

In this paper, we present two algorithms for efficiently aggregating link state information needed for quality-of-service (QoS) routing. In these algorithms, each edge node in a group is mapped onto a node of a shufflenet or a node of a de Bruijn graph. By this mapping, the number of links for which state information is maintained becomes aN (a is an integer, N is the number of edge nodes) which is significantly smaller than N2 in the full-mesh approach. Our algorithms also can support asymmetric link state parameters which are common in practice, while many previous algorithms such as the spanning tree approach can be applied only to networks with symmetric link state parameters. Experimental results show that the performance of our shufflenet algorithm is close to that of the full-mesh approach in terms of the accuracy of bandwidth and delay information, with only a much smaller amount of information. On the other hand, although it is not as good as the shufflenet approach, the de Bruijn algorithm also performs far better than the star approach which is one of the most widely accepted schemes. The de Bruijn algorithm needs smaller computational complexity than most previous algorithms for asymmetric networks, including the shufflenet algorithm.

• Journal of Information Management
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• v.32 no.1
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• pp.1-22
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• 2001

In traditional environment, user must search each journal OPAC, bibliographic DB, and full-text DB and E-Journal separately until user finds scientific and technology informations that he needs. The purpose of this study is to build one-click service system of Journals that supports integrating search. This system provides various functions, such as, journal browsing, journal search, article search, alert function, my library, document delivery service by integrating databases and electronic journals. Users search all information sources through journal OPAC and acquire journal full-text by single interface.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.117-120
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• 2002

In this paper, we construct cryptographic accelerators using hardware Implementations of HMACS based on a hash algorithm such as MD5.It is basically a secure version of his previous algorithm, MD4 which is a little faster than MD5 The algorithm takes as Input a message of arbitrary length and produces as output a 128-blt message digest The input is processed In 512-bit blocks In this paper, new architectures, Iterative and full loop, of MD5 have been implemented using Field Programmable Gate Arrays(FPGAS). For the full-loop design, the performance Is about 500Mbps @ 100MHz

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.157-160
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• 2002

This paper proposed a guideline for selecting the arithmetic circuit architecture. The guideline incorpo-rates the new concept of PDSP (power-delay-size product) and the weighting method. HSPICE simulations havc been performed to several full adders in order to prove the validity of the proposed guideline. We applied this guideline to select an optimized FA (full adder) architecture and successfully implemented the DAC's digital blocks.

• Journal of the Korean Institute of Telematics and Electronics
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• v.15 no.3
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• pp.7-10
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• 1978

A method of full wave rectification is proposed which is accomplished by an inverter circuit including R-feed back. Both halves of the input cycle can be presented in the out put by composing a conductive half cycle and an inactive half cycle substituted by feed back in the cut off state.