• ETRI Journal
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• 제34권4호
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• pp.629-632
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• 2012

This letter investigates the combination of the Chase-2 and sum-product (SP) algorithms for low-density parity-check (LDPC) codes. A simple modification of the tanh rule for check node update is given, which incorporates test error patterns (TEPs) used in the Chase algorithm into SP decoding of LDPC codes. Moreover, a simple yet effective approach is proposed to construct TEPs for dealing with decoding failures with low-weight syndromes. Simulation results show that the proposed algorithm is effective in improving both the waterfall and error floor performance of LDPC codes.

• 제어로봇시스템학회논문지
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• 제11권3호
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• pp.200-206
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• 2005

In this paper, a redundancy management system for aircraft is studied, and FDI (Fault Detection and Isolation) algorithm of inertial sensor system is proposed. UAV system cannot allow triple or quadruple hardware redundancy due to the limitations on space and weight. In the UAV system with dual sensors, it is very difficult to identify the faulty sensor. Also, conventional FDI method cannot isolate multiple faults in a triple redundancy system. In this paper, hardware based FDI technique is proposed, which combines a parity equation approach with the wavelet based technique, which is a model-free FDI method. To verify the effectiveness of the proposed FDI method, numerical simulations are performed.

• 전자공학회논문지B
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• 제32B권12호
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• pp.1652-1662
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• 1995

In this paper, a hybrid neural network is proposed to improve the learning ability of a neural network. The union of the characteristics of a Self-Organizing Neural Network model and of multi-layer perceptron model using the backpropagation learning method gives us the advantage of reduction of the learning error and the learning time. In learning process, the proposed hybrid neural network reduces the number of nodes in hidden layers to reduce the calculation time. And this proposed neural network uses the fuzzy feedback values, when it updates the responding region of each node in the hidden layer. To show the effectiveness of this proposed hybrid neural network, the boolean function(XOR, 3Bit Parity) and the solution of inverse kinematics are used. Finally, this proposed hybrid neural network is applied to the visual tracking control of a PUMA560 robot, and the result data is presented.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1075-1080
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• 2010

There have been lots of researches for High Performance Digital Signal Processing performance enhancement on a GPU(Graphic Processor Unit). These kinds of parallelizing can enable massive signal processing, so we can have advantage's of processing various of signal processing standards with GPU. In this paper we introduce Low Density Parity Check(LDPC) which is one of the Foward Error Correction(FEC). And we have achieved computational time reduce by using CUDA as a parallelizing scheme.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2172-2175
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• 2003

본 논문에서는 DC 억압능력이 없거나 부족한 코드에 만족할 만한 DC 억압능력을 갖도록 하기 위한 멀티모드코드 방식을 제안한다. 제안한 멀티모드코드는 데이터열의 다중화를 위해 Pseudo Scrambling Technique를 사용하며, 다중화 된 데이터열의 변조를 위해 DC-free RLL(d, k) Code를 사용하는 특징을 가진다. 제안한 방법에서는 Sync 코드워드의 패리티를 다중화 정보로 사용하여 입력데이터를 2개의 데이터 열로 다중화하고, 2개로 다중화 된 데이터 열에 대해 DC-free RLL(d, k) Code를 사용하여 코드워드로 변환하며, 코드워드로 변환된 2 개의 코드워드 열에 대해 DC 성분이 적은 코드워드 열 하나를 선택하여 변조 스트림으로 출력한다. 본 논문에서는 Sync 코드워드의 패리티를 다중화 정보로 사용하여 별도의 Redundancy를 부가하지 않고 DC 억압성능을 향상시킬 수 있었다.

• 한국환경보건학회지
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• 제22권3호
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• pp.8-16
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• 1996

Effects of water extract of aloe vera on lead-induced neurotoxicity were investigated in sciatic nerve isolated from rat. The mechanism on toxicity reduction by measuring activities of axonal enzymes, metabolism of myo-inositol in nerve, lead concentration in several organs and so on were further examimed. In the lead-treated rats, the transport rate of axonal enzyme, such as acetyl cholinesterase and choline acetyltransferase, was reduced by from 50% to 30% respectively. Reduction in myo-inositol concentration and $Na^+/K^+$ ATPase activity were also observed in sciatic nerve from lead-treated rat. However, the aloe extract administration significantly eliminated the impairment and maintained myo-inositol concentration to about 85% of normal level. Also aloe extract promoted the excretion rate of lead which is accumulated in blood, sciatic nerve and kidney. These results suggest that lead-induced neurotoxicity was significantly reduced by administration of aloe extract and the mechanism might be partly increase in kidney excretion rate of lead and parity normalization of $Na^+/K^+$ ATPase activity which is critical factor in order to keep nerve maintaining normal myo-inositol level.

• 한국전자통신학회논문지
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• 제7권2호
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• pp.317-325
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• 2012

본 논문에서 우리는 LDPC 부호의 부호화 문제를 고려한다. 특히 재킷 패턴과 순환 치환 행렬을 사용함으로써 리차드슨의 하삼각 행렬과 유사한 간단한 LDPC 부호를 제안한다. 이 부호화 기법은 다양한 부호율을 갖도록 확장할 수 있다. 또한 단순한 행렬 처리에 근거하여 다양한 부호율을 갖는 복잡도가 낮고 간단한 부호기를 설계할 수 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1965-1966
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• 2008

The manipulation of Boolean functions is a fundamental part of computer science, and many problems in the design and testing of digital systems can be expressed as a sequence of operations. It is mainly a paper of our research on the techniques of Boolean function manipulation using Binary Decision Diagram(BDDs) and their applications for VLSI CAD System. In many practical applications related to digital system design, it is a basic technique to use ternary-valued functions. In this paper, we discuss the methods for representing logical values.

• 한국정보보호학회:학술대회논문집
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• 한국정보보호학회 1991년도 학술발표논문집
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• pp.40-48
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• 1991

McEliece 공개키 암호체계에 대한 새로운 암호해독적 공격이 제시되어진다. 기존의 암호해독 algorithm이 exponential-time의 complexity를 가지는 반면, 본고에서 제시되어지는 algorithm은 polynomial-time의 complexity를 가진다. 모든 linear codes에는 systematic generator matrix가 존재한다는 사실이 본 연구의 동기가 된다. Public generator matrix로부터, 암호해독에 사용되어질 수 있는 새로운 trapdoor generator matrix가 Gauss-Jordan Elimination의 역할을 하는 일련의 transformation matrix multiplication을 통해 도출되어진다. 제시되어지는 algorithm의 계산상의 complexity는 주로 systematic trapdoor generator matrix를 도출하기 위해 사용되는 binary matrix multiplication에 기인한다. Systematic generator matrix로부터 쉽게 도출되어지는 parity-check matrix를 통해서 인위적 오류의 수정을 위한 Decoding이 이루어진다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권6호
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• pp.956-965
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• 1999

Genetic selection and sophisticated management technology have produced modern sows which excel in litter size and milk production. Recent research has identified nutritional innovations which may enhance productivity of the high producing sow. Selected research in three areas which have the potential to enhance reproductive performance are summarized in this report. First, preliminary evidence indicates that organic chromium may enhance litter size and conception rate. Secondly, high producing sows, particularly primiparous sows, required higher protein/lysine in late gestation and or lactation to optimize weaning weight and subsequent litter size. Valine and isoleucine, but not leucine, have been shown to enhance milk production. Phased feeding programs with diet cost partitioned toward gilts and away form parity 3 to 8 sows have been suggested as a means of improving reproductive performance in young sows. Lastly, recent research with sufficient sow numbers to document the effect of dietary fiber on reproductive performance has shown that sows fed fiber farrowed and weaned more pigs.