• Information and Communications Magazine
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• v.28 no.11
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• pp.66-75
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• 2011

본고에서는 아인슈타인(1905) 특수상대성이론과 샤논(1948)의 정보이론의 탄생배경 중심으로 유도하였고, 이 아름다운 두 식을 비교, 설명하였다. 4G 무선 이동통신의 주파수 스펙트럼 효율을 증가시키기 위해, MIMO를 쓰고 샤논 캐퍼시티에 접근하기 위해 새로운 채널코딩 기술을 쓰고 있다. 모두 샤논의 손바닥 안에 있다.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.233-233
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• 2018

• Electrical & Electronic Materials
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• v.10 no.10
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• pp.1048-1055
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• 1997

• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.5
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• pp.863-874
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• 2021

Distributed key generation (DKG) with trustless setup is a cryptographic protocol that distributes Shamir secret shares of a private key to participants while keeping the actual private key hidden to the participants. Also, by extending it to a threshold signature protocol, digital signatures can be generated without construction of private keys. This paper proposes a recovery protocol maintaining trustless setup assumptions, in particular to the useful (1,3) share structure. The proposed protocol meets same levels of security requirements with DKG in terms of correctness and secrecy. The protocol can also enable delegation and revocation of digital sign rights for blockchain-based asset management.

• Korean Journal of Environment and Ecology
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• v.19 no.3
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• pp.312-326
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• 2005

The purpose of this study is to provide data for conservation and ecological management of Pinus densiflora forest by analyzing ecological characteristics and the change of Pin us densiflora community structure for fifteen years in Namsan(Mt.). The actual vegetation of Pinus densiflora forest was divided into total six types and fifteen detail types. According to the results of TWINSPAN analysis of Pinus densiflora forest, there were fourty-four plots(unit: 400 m') and it was classified into five community types. The dominant species were Pinus densiflora in canopy layer, Styrax japonica in the understory layer and Stephanandra incisa with Rhododendron mucronujatum in the shrub layer. The index of shannon's diversity was from 1.5980 to 1.1485 per $400m^2$and the range of species number was from seventeen to twenty-two. As a result of the change of Pin us densinora forest structure, the importance percentage(1.p.) of Pinus densi. nora$(I.P.:\;77.9\%\rightarrow50.6\%) was decreased, Styraxjaponica$(I.P.:\;5.3\%\rightarrow22.6\%), Prunus sargen $(I.P.:\;1.5\%\rightarrow9.2\%) and Stephanandra incisa$(I.P.:\;3.5\%\rightarrow7.7\%) were increased for fifteen years. Based on standard of $2,000m^2$unit area, shannon's diversity changed 1.1719 into 0.8829 and species number changed thirty-four into twenty-one.

• Korean Journal of Environment and Ecology
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• v.20 no.2
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• pp.188-199
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• 2006

The purpose of this study was to provide data for conservation management of Pinus densiflora forest by analyzing ecological characteristics and the change of Pinus densiflora community structure for fifteen years in Gayasan National Park. According to the results of TWINSPAN analysis of Pinus densiflora forest, there were twenty plots(unit: $500m^2$)and it was classified into seven community types. The dominant species were Pinus densiflora in canopy layer, Carpinus laxiflora, Quercus variabilis, Quercus serrata in the understory layer and Sasa borealis, Rhododendron mucronulatum, Rhus trichocarpa in the shrub layer. The index of shannon's diversity was from 0.6803 to 1.2559 per $500m^2$ and the range of species number was from twenty-seven to fourty. As a result of the change of Pinus densiflora forest structure, the importance percentage(I.P.) of Carpinus laxiflora, Quercus variabilis, Quercus serrata in the understory layer were increased for fifteen years. The index of shannon's diversity changed $0.2608{\sim}1.0124\;into\;0.5547{\sim}1.2567\;per\;500m^2$ and species number changed $14{\sim}26\;into\;26{\sim}34$ for fifteen year.

• Journal of Internet Computing and Services
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• v.23 no.3
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• pp.21-33
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• 2022

This paper is to suggest the secure secret sharing system in order to outstandingly reduce the damage caused by the leakage of the corporate secret. This research system is suggested as efficient P2P distributed system kept from the centrally controlled server scheme. Even the bitcoin circulation system is also based on P2P distribution scheme recenly. This research has designed the secure circulation of the secret shares produced by Threshold Shamir Secret Sharing scheme instead of the shares specified in the torrent file using the simple, highly scalable and fast transferring torrent P2P distribution structure and its protocol. In addition, this research has studied to apply both Shamir Threshold Secret Sharing scheme and the securely strong multiple user authentication based on Collaborative Threshold Autentication scheme. The secure transmission of secret data is protected as using the efficient symmetric encryption with the session secret key which is safely exchanged by the public key encryption. Also it is safer against the leakage because the secret key is effectively alive only for short lifetime like a session. Especially the characteristics of this proposed system is effectively to apply the threshold secret sharing scheme into efficient torrent P2P distributed system without modifying its architecture of the torrent system. In addition, this system guaranttes the confidentiality in distributing the secret file using the efficient symmetric encryption scheme, which the session key is securely exchanged using the public key encryption scheme. In this system, the devices to be taken out can be dynamically registered as an user. This scalability allows to apply the confidentiality and the authentication even to dynamically registerred users.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.773-776
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• 2001

열악한 전송 환경에서 고품질, 고신뢰성 통신을 지속적으로 하기 위해서 오류 정정 부호는 필수 적이다. 최근에 반복 복호를 통해 샤논의 채널 용량 한계에 근접하는 터보 부호와 LDPC부호가 가장 관심을 불러일으키고 있다. 반복 복호법은 성능 면에서는 우수해 지나 이에 따른 계산량 증가와 지연이 수반된다. 따라서 본 논문에서는 모의 실험을 통한 수신 데이터를 이용, SNR을 추정하여 LDPC 부호의 최대 반복 복호수에 따른 계산량과 지연을 효과적으로 줄일 수 있는 적응적 반복 복호수 설정 방식을 제안한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1225-1226
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.429-430
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• 2009