• Proceedings of the Korea Information Processing Society Conference
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• 2023.05a
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• pp.119-122
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• 2023

양자 컴퓨터가 현대 암호 시스템의 보안성을 위협하고 있음에 따라, 최근 잠재적인 양자 공격들에 대한 분석 연구들이 다수 발표되고 있다. 공개키 암호인 RSA와 ECC의 경우, Shor 알고리즘에 의해 다항시간 내에 해결됨으로써 보안성이 완전히 붕괴되는 반면, 대칭키 암호는 Grover 알고리즘에 의해 보안 강도가 제곱근으로 감소하기 때문에 키 길이를 증가시킴으로써 기존 보안성을 복구할 수 있다. 이론적으로 Grover 알고리즘은 보안성을 훼손시키지만, 현실적인 공격 난이도가 매우 높음에 따라 대상 암호에 대한 양자 회로 최적화 구현이 중요하다. 이에 본 논문에서는 블록암호 RC5를 양자 회로 상에서 최적화하고 이를 기반으로 Grover 공격 비용을 추정한다. 마지막으로, 추정한 비용을 NIST의 양자 후 보안 강도 평가와 함께 비교함으로써 RC5에 대한 양자 암호 분석을 수행한다.

• Korean journal of communication and information
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• v.55
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• pp.74-99
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• 2011

This article tries to find out some regulatory facts to improve and vitalize roles of social media such as facebook, twitter, etc in the election campaign. For this goal, a theoretical approach is based on the agnostic and open aspects of the regulation system of election. Case study and in-depth interview were used as research methods in this article. The results are as follows. First, some differences are in the election regulatory system regarding the roles of social media in UK, US, Japan and Korea. The election public sphere systems of these countries categorized to the types of legal factors to control political communications in election public sphere; free-speech oriented system(UK. US), limited free-speech oriented system(Korea), normative-oriented system(Japan). Second, most respondents answered they agreed with some improvement ideas to reflect needs of netizen and academic who suggest to minimize regulatory burdens on social media in the political communication during the election campaign.

• Korean journal of communication and information
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• v.76
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• pp.183-219
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• 2016

In light of the recent increase in new independent spaces within the field of artistic production, this study seeks to examine the daily experience and art practice of agents in such spaces. In-depth interviews were conducted with fifteen emerging artists, who manage new independent art spaces and participate actively in related activities, and the significance of their activities was analyzed. An important theoretical foundation of this study is Bourdieu's concept of the field of cultural production. According to Bourdieu, in order to understand a specific field, the habitus of agents must be studied together with the structure of the field. This study found that individuals belonging to the same or a close generation exhibit similar attitudes to life based on shared experiences, and they can be connected to their art practice. Most agents of new spaces did not have high expectations for success, and chose to practice art independently while bonding with their peers and enjoying the moment rather than wait for recognition or funding from external sources. Their self-fulfilling habitus is condition-specific and can be regarded as a form of flexible art practice. Given the poor conditions of today's field of artistic production, this is likely to serve as an advantage in entering the field and in position-taking. The social significance of this study lies in the fact that the aforementioned characteristics of the agents of independent production spaces not only reflect the current field of artistic production but also other fields of cultural production at large in our society.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.14 no.1
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• pp.19-33
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• 2002

A numerical method to efficiently secure necessary design informations of the hydraulic characteristics of rubble mound breakwater was attempted here. The method combines the exterior wave field with the interior wave field which is formulated incorporating porous media flow inside the breakwaters. An approximate method based on the long wave assumption was used for the exterior wave field while a boundary element method was used for the interior wave field. A hydraulic experiment was also performed to verify the validity of the numerical analysis. The numerical results were compared with experimental data and results from existing formulae. They generally agreed in both reflection and transmission coefficients. The calculated pore pressures also showed a similar pattern with experimental data, even if they gave some significant differences in their values fur some cases. The main cause of such differences can be attributed to the strongly nonlinear wave field occurring on the frontal slope of the breakwater. The direct input of dynamic pressures(measured from hydraulic experiment) into the numerical method was suggested as a promising method to enhance the predictability of pore pressures.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.985-988
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• 2008

This paper introduces a new TR-UWB system, using frequency-domain components of UWB pulses. This is achieved by separating converted frequency-components into real and imaginary parts, and both parts are correlated and effectively combined. We make an analysis that the new scheme improves performance compared with a conventional by complex correlation computing. The simulation results confirmed that the proposed scheme has better performance than existing system.

• The Journal of Information Technology
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• v.3 no.4
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• pp.41-53
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• 2000

The Purpose of this is to examine the relation verween tourist motibation and attribute of attractions closely. The tourist morivationmade a practical application of the functional theory, Which is one of the theories explaining an attitude and a change in attitude, and was catagorized. the potential tourists full of the natural attributes, n in the full of pursuit of the cultural attributes, vut in the fewest pursuit of the attributes of attractions such as low price and convenient transportation .

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.11
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• pp.881-889
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• 2000

프로그램의 실행시간은 캐쉬메모리의 효율적 사용과 밀접한 관계가 있다. 특히 간섭 실패는 프로그램의 성능에 큰 영향을 미치지만 나타나는 형태가 불규칙적이므로 예측하기가 매우 어렵다. 본 논문에서는 직접 사상 캐쉬전략을 사용한 완전 중첩 루프 내 배열의 캐쉬 실패율(cache miss ratio)을 구하는 분석적 모델을 제시한다. 논문에서 제시한 모델을 임의의 캐쉬 위치에 각 배열이 접근한 시간을 기반으로 다음주기에서 캐쉬 실패의 발생 여부를 예측하는데, 간섭으로 발생한 캐쉬 실패 개수에 대해 기존에 제시된 모델보다 더 빠르고 정확한 예측이 가능하다. 특히, 한문장의 수행시간 예측시간은 배열의 크기와 독립적이기 때문에, 전체 프로그램의 수행시간 예측은 배열의 크기 및 문장의 반복 회수 배만큼 빠른 결과를 보여준다. 본 모델은 프로그램의 성능예측 뿐만 아니라 데이터 지역성의 최적화, 캐쉬 구성, 스케쥴링 등에서도 이용 가능하다.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06c
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• pp.303-308
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• 2007

최근에 제안된 감독 지식을 융합하는 강화 학습 기법인 potential-based RL 기법의 효용성은 이론적 최적 정책으로의 수렴성 보장으로 증명되었고, policy-reuse RL 기법의 우수성은 감독지식을 융합하지 않는 기존의 강화학습과 실험적인 비교를 통하여 증명되었지만, policy-reuse RL 기법을 potential-based RL 기법과 비교한 연구는 아직까지 제시된 바가 없었다. 본 논문에서는 potential-based RL 기법과 policy-reuse RL 기법의 실험적인 성능 비교를 통하여 기법이 policy-reuse RL 기법이 policy-reuse RL 기법에 비하여 더 빠르게 수렴한다는 것을 보이며, 또한 policy-reuse RL 기법의 성능은 재사용하는 정책의 optimality에 영향을 받는다는 것을 보인다.

• Proceedings of the Korean Society for Information Management Conference
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• 2006.08a
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• pp.239-248
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• 2006

현대 도서관은 전자자원(electronic resource)의 양적인 급증으로 인하여, 전통적인 수서정책이나 관리시스템만으로 효과적인 관리가 점차 어려워지고 있다. 이러한 문제를 해결하기 위해 도서관들은 전자자원 관리에 대한 시스템적인 이론과 알고리즘을 개발하고 있다. 이 점에 착안하여 이 연구에서는 급증하고 있는 전자자원의 효율적 관리와 활용을 위한 필수 전자자원 관리용 메타데이터의 제안과 이를 이용한 효율적 관리방안을 제안하였다. 이 연구의 결과로 도출된 전자자원 관리용 메타데이터의 요소들은 향후 전자자원 관리시스템 개발에 있어서 기초자료로 활용될 것이다.

• Journal of the Korea Society of Computer and Information
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• v.8 no.1
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• pp.90-96
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• 2003

In this paper, arranged the isotropic point source of N number with the structure which is identical with the receive area. And against the array structure which has the radiation pattern which is identical with the receive area it researched. The arranged the element space flees grating lobe and in order to set the characteristic of optimum with half-wave equally space it selects. After inducing the array factor of each array structure, it calculated a radiation pattern. As a result of, the radiation pattern of the each Planar array antenna with structure of the receive area was similar and the possibility of getting an beam characteristic it was.