• 한국산학기술학회논문지
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• 제12권3호
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• pp.1387-1394
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• 2011

이 논문에서는 OFDM Modem의 심볼 타이밍 옵셋 동기화 블록에 대한 저면적 구조를 제안한다. 심볼 타이밍 동기화 블록에서의 곱셈연산을 디지털 필터 구조의 개념을 도입하여 저면적 구조를 유도하였다. 즉 곱셈연산을 CSD(Canonic Signed Digit) 방식과 CSS(Common Sub-expression Sharing) 방식의 덧셈기를 사용한 구조를 제안하였다. 제안 구조에 대한 Verilog-HDL 코딩과 합성을 통하여 $0.264mm^2$로 구현하였으며, 이는 기존 구조의 $0.723mm^2$와 비교하여 63.54%의 구현 면적 감소를 달성하였다. 따라서 제안된 구조는 OFDM 시스템의 심볼 타이밍 동기화기에 효율적으로 사용 될 수 있을 것이다.

• 한국실내디자인학회논문집
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• 제23권3호
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• pp.29-38
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• 2014

This paper is to analysis covering and exposing elements through surface in the spirit of the time through the meaning of relationship between structure and symbol(ornament) in the theory of dressing of Gottfrid Semper. In other words, The purpose is to illuminate how complementary tectonic between structure and symbolic of an architecture surface is expressed in accordance with the biased required conditions relating with the paradigm of the era. The advancement of the new method of tectonic and the new aesthetic taste have a deep relation with the reconsidering the dichotomy classification discussing a dominant position between structure and symbol(ornament). Expression of surface representing the era comes across the combined interpretation of technology, structure, and the non-physical culture's art of the community and the era.

• 디지털산업정보학회논문지
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• 제10권4호
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• pp.29-35
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• 2014

The formula contains up between the text and the structural information, as well as their mathematical symbols. Research on-line or off-line recognition formula is underway actively used in various fields, and various forms of the equation are implemented recognition system. Although many documents are included in the various formulas, it is not easy to enter a formula into the computer. Recognition of the expression is divided into two processes of symbol recognition and structural analysis. After analyzing the location information of each character is specified to recognize the effective area after each symbol, and to the structure analysis based on the proximity between the characters is recognized as an independent single formula. Furthermore, analyzing the relationship between the front and back each time a combination of the position relationship between each symbol, and then to add the symbol which was able to easily update the structure of the entire formula. In this paper, by using a scanner to scan the book formula was used to interpret the meaning of the recognized symbol has a relative size and location information of the expression symbol. An algorithm to remove the formulas for calculation of the number of formula is present at the same time is proposed. Using the proposed algorithms to scan the books in the formula in order to evaluate the performance verification as 100% separation and showed the recognition rate equation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.487-489
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• 2005

This paper proposes a symbol timing recovery method that is simple in structure and can provide high speed symbol synchronization. Transmitter and receiver are not synchronized in communication systems using digital modulation. Receiver should search the timing variation of transmitter continuously. The proposed timing recovery method searches sample position by comparing previous sample value with next sample value. This method can be applied to digital and optical transceivers with high data rate.

• 한국통신학회논문지
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• 제21권6호
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• pp.1554-1566
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• 1996

In this paper, a new symbol timing algorithm for a magnetic recording system as HDD, is proposed. Above all, the Lorentzian channel model applied, the distortion and the attenuation problems of playback signals at high speed and storage density were considered. The structure and the operation of popular data detectors for HDD were understood, and the adopted symbol timing algorithm were profoundly analyzed. On the basis of these understanding and analysis, a new symbol timing algorithm for high density HDD was proposed, and the performance evaluation of this proposed algorithm was done.

• 한국통신학회논문지
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• 제27권2C호
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• pp.170-183
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• 2002

본 논문에서는 OFDM(Orthogonal Frequency Division Multiplexing) 전송방식을 채택한 DVB-D(Digital Video Broadcasting-Terrestrial) 시스템의 효율적인 주파수 및 심볼 동기 구조를 제안하였다. 주파수 동기시 고려해야 할 사항은 정규화된 주파수 오프셋(실제 주파수 오프셋/부반송파 간격)의 소수부가 $\pm$0.5 부근에 위치할 때, 알고리즘의 추정 성능이 안정적이지 못하여 동기화에 필요한 심볼이 많이 요구된다는 점이다. 본 논문에서 제안하는 주파수 동기 구조는 대략적인 주파수 동기를 여러 심볼 동안 추정한 평균값을 이용하여 정규화된 주파수 오프셋의 소수부가 $\pm$0.5 부근에 위치할 때의 모호성을 해결하고, 대략과 미세 주파수 동기를 동시에 추정하여 보상하는 효율적인 구조이다. 또한 기존의 OFDM 심볼 동기 수행시 대략과 미세로 나누는 동기 구조를 변경하여 윈도우 오프셋이 항상 보호구간 내의 일정 범위 안으로 잔류하도록 만들어 대략적인 심볼 동기 만으로도 다중경로 페이딩 채널에서 시스템의 성능 열화 없이 하드웨어 구현이 용이한 심볼 동기 구조를 제안하였다. 그리고, 광범위한 시뮬레이션에 의해 본 제안 방식의 우수성을 증명하였다.

• 한국통신학회논문지
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• 제21권10호
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• pp.2660-2669
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• 1996

In this paper, it is called nonlinear-symbol CPFSK(NCPFSK) which is modulated by the nonlinear function of information carrying phase function within all symbol interval produce time invariant trellis structure. In general, the bit error probability performance of CPFSK modultion scheme within given signal constellation is determined from the number of memory elementsof continuous phase encoder, i.e. number of state. In this paper the number of state of analyticall designed NCPFSK is time invariant. And the nonlinear symbol mapping function of the proposed moudlation produces the nonlinear symbol andthe phase state of the modulation for updating the phase function of NCPFSK. It si shown in this paper nonlinear symbol CPFSK with multiple TCM to make further improvements in d$^{2}$, and analyzed BER performance in AWGN channel envioronments.hannel envioronments.

• 한국통신학회논문지
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• 제27권1B호
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• pp.66-78
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• 2002

본 논문에서는 OFDM(Orthogonal Frequency-Division Multiplexing) 기반의 무선 LAN 시스템을 위한 새로운 심볼 옵셋 추정기법을 제안한다. OFDM 심볼에 심볼간 간섭(Inter-Symbol Interference: ISI)과 채널간 간섭(Inter-Channel Interference: ICI)이 없는 경우 추정된 채널의 임펄스 응답은 심볼 옵셋만큼 순환 이동한다. 전형적인 다중경로 무선채널의 전력 지연 프로파일은 지수적 감소 함수로 모델링 할 수 있으며 대부분의 에너지가 임펄스 응답의 앞부분에 주로 집중된다. 제안된 기법은 이러한 성질을 이용하여 먼저 심볼 옵셋만큼 순환 이동된 다중 경로 채널의 임펄스 응답을 추정한 후 유한 길이의 이동 윈도우를 사용하여 임펄스 응답의 부분 평균 전력을 구한다. 그리고, 부분 평균 전력 중에서 최대값을 갖는 이동 윈도우의 인덱스로부터 심볼 옵셋을 추정한다. 제안된 기법은 임펄스 응답의 추정 과정에서 잡음의 영향을 감소시키고, ISI와 ICI를 제거시키며 최소의 오버헤드를 얻기 위해 반복적 구조의 훈련 신호를 사용한다. 실내 무선 채널 모델에서의 모의실험을 통해 제안된 기법의 성능을 검증한다.

• 전자공학회논문지A
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• 제33A권7호
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• pp.34-43
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• 1996

In this paper a simpel algorithm for all-digial high speed symbol synchronization is proposed. The proposed algorithm has a structure based on BECM (band-edge component maximization). The algorithm requires only tow samples per symbol for its operation. We analyze and evaluate performance of the proposed algorithm. Simulation results reveal that the proposed algorithm has better performance than the gardner algorithm in narrowband.

• 한국실내디자인학회논문집
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• 제15권6호
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• pp.52-59
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• 2006

The study is intended to clarify the ideologies and principles applied to the formative expression of church architecture which is contained both the God and human. Iconography as the relation between described target and the meaning as meaning analysis especially emphasized since the religious reason in religious art. Iconography is the area of discussing rules and habits and involved in the pieces of transition from the piece of experience obtained by sensing to the one of the ethical structure. N. L. Prak who apply meaning theory of E. Panofsky who distinguish between iconography and iconology clear relation of mental foundation which characteristics of shape of art and its concretion in architecture categorized the shape of meaning in three steps. Among them, conscious symbol and unconscious symbol correspond to iconography and iconology of Panofsky respectively. The symbol is mainly showed in religious architecture and is not related to simple practical architecture. Such symbol system can be important discussion objects in modern church architecture and necessary expressional system for expressional characteristics.