• Title/Summary/Keyword: self reference

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Message Coding Technique for Self-reference Watermarking (자기 참조 워터마킹을 위한 메시지 코딩 기법)

  • 전영균;최창렬;정제창
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2002.11a
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    • pp.159-162
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    • 2002
  • 데이터에 삽입되어 있는 워터마크를 제거하려는 공격기법이 점차 발전되면서 여러 가지 워터마킹 알고리즘이 등장하게 된다. 보통 워터마크를 제거하기 위해서는 워터마크 신호의 동기를 제거하는 동기-제거(De-Syncronization) 공격 방법을 이용한다. 이런 공격에 대처하기 위한 워터마킹 방법으로는 세 가지로 분류할 수 있는데, 공격에 영향을 받지 않는 영역(invariant domain)에 워터마크를 삽입하는 방법, 템플릿(template)을 이용한 방법, 자기 참조(self-reference)를 이용한 기법 등이 있다. 본 논문에서는 공간 영역에서의 자기 참조 워터마킹 방법을 소개하고, 이에 적합한 메시지를 삽입하고 검출하는 방법에 대해 제안한다. 삽입하려는 메시지와 Reed-solomon Code를 이용하여 만든 부가적인 정보를 QOS(Quasi-orthogonal sequences)방법과 DSSS를 이용하여 만든 다음 키 값을 이용하여 뒤섞으면 워터마킹 블록을 자기 참조 워터마킹 방법으로 영상에 삽입하게 된다. 그 결과 일반적 필터링 공격에는 95% 이상 검출됐고, JPEG 압축 파라미터 60에서도 97% 이상 검출되었다.

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State-Space Pole-Placing self-Tuning Controller Using Input-Output Values (입출력값에 의한 상태공간 극배치 자기동조제어기)

  • Kim, Yeong-Gil;Park, Min-Yong;Lee, Sang-Bae
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.22 no.5
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    • pp.17-23
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    • 1985
  • This paper describes a method for the design of a self-tuning controller of single-input/single-output systems with system noises and obsrrvation noises. The method uses state-space techniques to assign the closed-loop system poles to desired locations, but the control law is made up of process input and output measurement values, so that state estimation is unnecessary. Also the difficulties of tracking of reference inputs in state.space pole-placing control are tackled by including the reference input in the cost function proposed by Beger.

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Design of SOFLIC for reactor rod control system in nuclear power plant (원자력발전소 원자로 제어봉 제어계통에 대한 자기조정 퍼지제어기 설계)

  • 남해곤;문채주;최홍관
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1995.10b
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    • pp.145-152
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    • 1995
  • This paper presents a novel SOFLIC(self organizing fuzzy logic intelligent controller) for reactor rod control system in nuclear power plant. The output of fuzzy controller is gener ated by using two signal : the error between reference and average temperature, and the error between reference and neutron flux-converted temperatures. Flexibility of the controller is enhanced by using self-organizing feature and the controller respond to variation of system parameter with more precision. performances of the SOFLIC and PID are simulated with the model developed for a nuclear power plant. The SOFLIC is superior to PID : SOFLIC provides more rapid load following capability. more robustiness for variation in process dynamics and minimization of engineer's mistakes in controller design.

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Appearance of Homo Economicus and Morals of Youth in Early Modern of Korea with reference to A Large River[Dae-Ha] (호모 이코노미쿠스의 출현과 주체적 각성의 사실성 - 김남천의 『대하(大河)』론)

  • Kim, Jongsoo
    • Cross-Cultural Studies
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    • v.35
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    • pp.79-95
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    • 2014
  • This article aims at rethinking on people of Modern styles in early modern period with reference to A Large River[Dae-Ha] written by Kim Nam-cheon at 1939. Park Sung-guoen could be called to Homo Economicus, first, have maximized of self-interest in rapid changes of Korea society with loan sharking, rising to upper class in new early modern era instead of traditional nobleman. Park Hyung-geol could be said romantic guy, second, have chased romatic love consist of three elements(love-sex-marriage). But he troubled his love affairs to his family members frustrated his will because of a bastard son. It is the model of situations, Kim Nan-cheon intended to describe, that Homo Economicus became an object of envy among people in early modern society as well as the choice has been hard in conflicting between family and lover, concretizing anachronism through history of family.

Rough surface characterization using off-axis digital holographic microscopy compensated with self-hologram rotation

  • Ibrahim, Dahi Ghareab Abdelsalam
    • Current Applied Physics
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    • v.18 no.11
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    • pp.1261-1267
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    • 2018
  • In this paper, an off-axis digital holographic microscopy compensated with self-hologram rotation is presented. The process is implemented via subtracting the unwrapped phase maps of the off-axis parabolic hologram and its rotation $180^{\circ}$ to eliminate the tilt induced by the angle between the spherical object wave O and the plane reference wave R. Merit of the proposed method is that it can be done without prior knowledge of physical parameters and hence can reconstruct a parabolic hologram of $1024{\times}768$ pixels within tens of milliseconds since it doesn't require a digital reference wave. The method is applied to characterize rough gold bumps and the obtained results were compared with those extracted from the conventional reconstruction method. The comparison showed that the proposed method can characterize rough surfaces with excellent contrast and in realtime. Merit of the proposed method is that it can be used for monitoring smaller biological cells and micro-fluidic devices.

A Speed Control of Stepping Motor Using a Self-Tuning Regulator

  • Kim, Young-Tae;Kim, Sei-Yoon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.11
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    • pp.69-75
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    • 2009
  • In this paper, a self-tuning regulator for a speed control of a permanent magnet type stepping motor is proposed. The self-tuning theory provides a nonlinear modeling of a stepping motor drive system and can provide the controller with information regarding the reference variation and parameter variation of the stepping motor through the on-line estimation. The proposed self-tuning regulator organize the positive feedback loop and IP(Integral-Proportional) type. Therefore, the proposed self-tuning regulator has a robust control capabilities during dynamic operation. The availability of the proposed controller is verified through experimental results.

A Study on the Materialism of Korean and Japan Undergraduates (한 . 일 여자대학생들의 물질주의성향)

  • 김정숙;권정원
    • Journal of Families and Better Life
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    • v.21 no.6
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    • pp.27-41
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    • 2003
  • The objective of this study was to find variables related to materialism of university students in Korea and Japan. A questionnaire research method was conducted and 477 samples were selected. Korean university students have higher materialism than Japanese university students. Korean undergraduates are influenced by reference group, but Japanese university students are influenced by group identity. Materialism of Korean university students are influenced by nonmaterialism, reference group, perception of living level, self concept, pocket money, mother's job. Materialism of Japan university students is influenced by nonmaterialism, group identity, perception of living level, grade. The strongest predictor of materialism of Korean university students is nonmaterialism, followed by reference group. The strongest predictor of materialism of Japanese university students is nonmaterialism, followed by group identity.

Unobtrusive Performance Evaluation of Reference Librarians in Academic Libraries of Korea (비 통보식 조사를 통한 참고사서 업무능력 평가)

  • Kim Youngshin
    • Journal of the Korean Society for Library and Information Science
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    • v.29
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    • pp.305-343
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    • 1995
  • The purposes of this study are to confirm the applicability of the unobtrusive evaluation to Korean libraries, to develop survey forms, check lists and evaluation criteria appropriate for Korean libraries, to analyze the relationship between the test variables and the performance level, to find out the causes of poor service if any, and to propose measures for improving the quality of reference services. The main results of the analyses are as follows : $\cdot$ The accuracy of answers was correlated to appropriateness of search process, way of providing answer, usage of language, approachability and use of second materials in the order named. That is, there was a strong correlation between accuracy and the variables related to librarian's behavior. $\cdot$ There was no statistically significant relationship between accuracy and the environmental aspects of reference department such as number of professional librarians, self-evaluation of reference collection, etc. $\cdot$ The main reasons for failing to give accurate answers were found to be weaknesses in understanding questions. developing search strategy logically and relating the querries to available information sources.

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