• 한국전자통신학회논문지
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• 제13권2호
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• pp.333-340
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• 2018

본 논문은 병렬 CRC 생성 방식을 적용한 BCH 코드 복호기를 소개한다. 기존에 사용되는 병렬 신드롬 생성기로 LFSR(: Linear Feedback Shift Register)을 변형한 방식을 사용하면 짧은 길이의 코드에 적용하는 데 많은 면적을 차지한다. 제안하는 복호기는 짧은 길이 코드워드의 복호화를 위해 병렬 CRC(: Cyclic Redundancy Check)에서 체크섬을 계산하는 데 사용되는 방식을 활용하였다. 이 방식은 병렬 LFSR과 비교해 중복된 xor연산을 제거해 최적화된 조합회로로 크기가 작고 짧은 전파지연을 갖는다. 시뮬레이션 결과 기존 방식 대비 최대 2.01ns의 지연시간 단축 효과를 볼 수 있다. 제안하는 복호기는 $0.35-{\mu}m$ CMOS 공정을 이용하여 설계하고 합성되었다.

• 한국철도학회논문집
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• 제8권1호
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• pp.1-5
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• 2005

This paper has presented the parallel cyclic redundancy check (CRC) technique that performs CRC computation in parallel superior to the conventional CRC technique that processes data bits serially. Also, it has showed that the implemented parallel CRC circuit has been successfully applied to the inductively coupled passive RFTD system working at a frequency of 13.56㎒ in order to process the detection of logical faults more fast and the system has been verified experimentally. In comparison with previous works, the proposed RFID system using the parallel CRC technique has been shown to reduce the latency and increase the data processing rates about 15％ In the results. Therefore, it seems reasonable to conclude that the parallel CRC realization in the RFID system offers a means of maintaining the integrity of data in the high speed RFID system.

• 한국통신학회논문지
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• 제18권1호
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• pp.83-91
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• 1993

디지틀 전송 시스팀에서 순방향 에러 제어(Forward Error Control) 방식으로 에러를 검출할 수 있는 성능과 구현의 용이함에 의해 Cyclic Redundancy Chedk(CRC) code가 널리 사용도고 있다. 즉, 간단한 몇개의 shift register와 modulo2 가산기를 이용하여 회로를 구성하고 입력 데이터 열을 직렬로 입력하면 최종적으로 shift register에 남아 있는 값이 CRC code가 되어 입력 데이터 열을 전송한 뒤 shift register의 값들을 순차적으로 전송하는 방식으로 전성 사의 에러를 검출하고 수정한다. 그러나 전송속도가 높아짐에 따라 직렬 데이터를 이용하여 CRC code를 생성하는 회로를 구현하는 것은 반도체 소자의 속도 제약 때문에 많은 어려움이 따른다. 따라서 본 논문에서는 주문형 반도체 개발시 반도체 소자의 속도 제약 문제를 해소하기 위하여 입력데이터 열을 병렬로 입력하여 직렬로 수행하는 방식과 동일한 방식으로 동작하는 병렬 CRC code 생성방식 및 syndrome 계산방식을 제안하였다.

• Structural Engineering and Mechanics
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• 제28권5호
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• pp.495-514
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• 2008

In this paper, experimental and theoretical investigations of the effect of the mean moment on the response and collapse of circular thin-walled tubes subjected to cyclic bending are discussed. To highlight the influence of the mean moment effect, three different moment ratios r (minimum moment/ maximum moment) of -1, -0.5 and 0, respectively, were experimentally investigated. It has been found that the moment-curvature loop gradually shrinks with the number of cycles, and becomes stable after a few cycles for symmetric cyclic bending (r = -1). However, the moment-curvature loop exhibits ratcheting and increases with the number of cycles for unsymmetric cyclic bending (r = -0.5 or 0). In addition, although the three groups of tested specimens had three different moment ratios, when plotted in a log-log scale, three parallel straight lines describe the relationship between the controlled moment range and the number of cycles necessary to produce buckling. Finally, the endochronic theory combined with the principle of virtual work was used to simulate the relationship among the moment, curvature and ovalization of thin-walled tubes under cyclic bending. An empirical formulation was proposed for simulating the relationship between the moment range and the number of cycles necessary to produce buckling for thin-walled tubes subjected to cyclic bending with different moment ratios. The results of the experimental investigation and the simulation are in good agreement with each other.

• Kyungpook Mathematical Journal
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• 제58권1호
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• pp.137-148
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• 2018

In the present paper we prove that in an almost Kenmotsu manifold with generalized $(k,{\mu})^{\prime}-nullity$ distribution the three conditions: (i) the Ricci tensor of $M^{2n+1}$ is of Codazzi type, (ii) the manifold $M^{2n+1}$ satisfies div C = 0, (iii) the manifold $M^{2n+1}$ is locally isometric to $H^{n+1}(-4){\times}R^n$, are equivalent. Also we prove that if the manifold satisfies the cyclic parallel Ricci tensor, then the manifold is locally isometric to $H^{n+1}(-4){\times}\mathbb{R}^n$.

• Steel and Composite Structures
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• 제36권2호
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• pp.197-211
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• 2020

Application of the steel ring as a type of seismic fuse has been one of the efforts made by researchers in recent years aiming to enhance the ductility of the bracing systems which in turn, possesses various advantages and disadvantages. Accordingly, to alleviate these disadvantages, an innovative bracing system with a diamond scheme equipped with a steel ring is introduced in this paper. In this system, the braces and yielding circular damper act in parallel whose main functionality is to increase ductility, energy absorption and mitigate drawbacks of the existing bracing systems, in which the braces and yielding circular damper act in parallel. To conduct the experimental tests, specimens with three types of rigid, semi-rigid and pinned connections were built and subjected to cyclic loading so that their performance could be analyzed. Promisingly, the results indicate both great applicability and efficiency of the proposed system in energy absorption and ductility. Moreover, it was concluded that as the braces and damper are in parallel, the use of a steel ring with smaller size and thickness would result in higher energy absorption and load-resisting capacity when compared to the other existing systems. Finally, to assess the potential of numerically modeling the proposed system, its finite element model was simulated by ABAQUS software and observed that there is a great agreement between the numerical and experimental results.

• Bulletin of the Korean Chemical Society
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• 제9권2호
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• pp.71-77
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• 1988

Boron trifluoride etherate on alumina catalyses the condensation of orcinol and monomethyl orcinol with cyclic allylic alcohols : in contrast to parallel reactions with boron trifluoride etherate in solution the products obtained undergo intramolecular cyclisations.

• Structural Engineering and Mechanics
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• 제9권4호
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• pp.375-382
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• 2000

Experimental investigation into the cyclic behaviour of sand plast brick masonry was performed on forty two square panels. The panels were subjected to cyclic uniaxial compression for two cases of loading: normal to bed joint and parallel to bed joint. Experimental data were used to plot the unloading-reloading curves for the entire range of the stress-strain curve. Mathematical expressions to predict the reloading and unloading stress-strain curves at various values of residual strain are proposed. A simple parabola and an exponential type formula are found adequate to model the unloading and reloading curves respectively. The models account for the potential effects of residual strain on these curves. Comparison of test results with the proposed mathematical expression shows good correspondence.

• 한국공간구조학회논문집
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• 제19권3호
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• pp.101-109
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• 2019

In order to develop the compatible damping device in various vibration source, a hybrid wall-type damper combining slit and friction damper in parallel was developed. Cyclic loading tests and two-story RC reinforced frame tests were performed for structural performance verification. As a result of the 5-cyclic loading test according to KBC-2016 and low displacement cyclic fatigue test, The hybrid wall type damper increased its strength and the ductility was the same as that of the slit damper. In addition, As a result of the two-layer frame test, the reinforced frame had about twice the strength of the unreinforced frame, and the story drift ratio was satisfied to Life Safety Level.

• 전기전자학회논문지
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• 제22권4호
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• pp.896-900
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• 2018

전통적으로 CRC 하드웨어는 선형 되먹임 시프트 레지스터를 이용하여 한 클럭 싸이클 당 하나의 비트를 처리하는 직렬 처리 방식을 사용하였다. 최근 다양한 응용 시스템에서 빠른 데이터 처리를 요구하면서 이를 만족시키기 위하여 다양한 병렬화 기법들이 제안되었고, Look-Ahead 병렬화 기법이 짧은 최대 경로 지연을 가지는 장점 덕분에 가장 널리 적용된다. 하지만 Look-Ahead 병렬 하드웨어의 경우 각 레지스터 값과 입력 데이터의 이동에 대하여 예측을 하여야 하기 때문에 직렬 하드웨어 대비 HDL 코드의 작성이 복잡하다. 따라서 본 논문에서는 다양한 CRC 다항식과 병렬화 계수를 지원할 수 있는 Look-Ahead 기반의 CRC 병렬화 하드웨어 생성기를 제안한다. 생성된 HDL 코드의 합성 결과를 분석함으로써 제안된 생성기의 활용 가능성을 판단한다.