• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.8
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• pp.1207-1212
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• 2013

Arithmetic operations over finite fields are widely used in coding theory and cryptography. In both of these applications, there is a need to design low complexity finite field arithmetic units. The complexity of such a unit largely depends on how the field elements are represented. Among them, representation of elements using a optimal normal basis is quite attractive. Using an algorithm minimizing the number of 1's of multiplication matrix, in this paper, we propose a multiplier which is time and area efficient over finite fields with optimal normal basis.

• The Korean Journal of Financial Studies
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• v.6 no.1
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• pp.93-117
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• 2000

본 논문의 목적은 1991년부터 1996년까지 부실이 된 상장기업 41개사와 이에 대응하는 118개 건전기업의 표본을 가지고 주요 재무정책변수를 이용하여 로짓분석에 의한 기업부실예측모형을 구축하는데 있다. 본 연구에서는 기존연구와는 달리 이론적으로 타당하고 재무경영자의 관심대상인 투자정책변수, 자본조달정책변수 및 배당정책변수를 가장 잘 반영한다고 판단되는 12개의 재무비율을 사전적으로 선정하였다. 이들 12개의 재무비율에 대해 부실기업과 건전기업을 가장 잘 판별할 수 있는 재무비율을 선정하기 위하여 프로파일 분석과 두 표본 t검정을 하였다. 그 결과 투자정책, 자본조달정책, 그리고 배당정책을 대표하는 변수로 자기자본순이익률, 총자본부채비율 및 배당율이 각각 채택되었다. 그리고 현금흐름변수를 추가하였다. 이 네 변수를 이용하여 로짓분석을 실행하였다. 먼저 부실 1년전부터 부실 5년전까지 각 연도별로 부실예측모형을 추정하였다. 부실 1년전의 추정모형에 의하면 총자본부채비율을 제외한 모든 계수의 부호는 (-)로 모두 기대했던 대로 나타났다. 전체적으로 볼 때 부실 4-5년 전에는 자기자본순이익률과 총자본부채비율이 기업부실에 유의한 영향을 주나 부실전 3년간은 현금흐름과 배당률의 크기가 부실에 영향을 주는 것으로 나타났다. 본 연구는 부실예측모형을 기업의 재무정책적인 관점에서 추정하였다는 데 그 의의가 있다고 할 수 있다.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.4 no.1
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• pp.9-16
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• 2011

In this paper, we propose an efficience transcoder architecture to support a simutaneous multibitrate output. First, we discuss about some architectures to realize this feature. Next, we explain the proposed architecture, it shares not only VLD-IQ but alse Q-VlD which have the same quantization step sizes each other. We anlyze the numbers of Q-VLC times per on Macroblock to the investigate an effect of sharing, and evaluate its computation complexity. The result of simulation, that complexity has an upper limit and it cn support any numbers of bitstream by about 3~6 times complexity than single output.

• Proceedings of the Korea Contents Association Conference
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• 2003.11a
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• pp.328-332
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• 2003

Since Jacquine introduced the image coding algorithm using fractal theory, many fractal image compression algorithms providing good quality at low bit rate have been proposed by Fisher and Beaumount et al.. But a problem of the previous implementations is that the decoding rests on an iterative procedure whose complexity is image -dependent. This paper proposes an iterative-free fractal image decoding algorithm to reduce the decoding time. In the proposed method, under the encoder previously with the same codebook image as an initial image to be used at the decoder, the fractal coefficients are obtained through calculating the similarity between the codebook image and a input image to be encoded. As the decoding process can be completed with received fractal coefficients and predefined initial image without repeated iterations, the decoding time could be remarkably reduced.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.5
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• pp.41-47
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• 2010

This paper has proposed parallel BCH, one of error correction coding methods which has been used to NAND flash memory for SSD(solid state disk). To alter error correction capability, the proposed design improved reliability on data block has higher error rate as used frequency increasingly. Decoding parallel process bit width is as two times as encoding parallel process bit width, that could reduce decoding processing time, accordingly resulting in one half reduction over conventional ECC.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.12
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• pp.97-106
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• 1999

We propose a new watermarking method to embed a label in a video which is robust against the change of the group of picture. The proposed method embeds labels in the pixel domain, but detects the label in the DCT frequency domain. For embedding a label, the size of watermark based on the human visual system is calculated to keep a quality of videos. A lookup table haying the pixel patterns and the sequences of a sign of DCT coefficients is used for detecting a label in the DCT frequency domain. In this paper, we analyze bit error rates for labels of videos compressed by MPEG2 using the central limit theorem and compare the simulation results with previous methods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.4
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• pp.434-440
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• 2003

Since Jacquine introduced the image coding algorithm using fractal theory, many fractal image compression algorithms providing good quality at low bit rate have been proposed by Fisher and Beaumount et al.. But a problem of the previous implementations is that the decoding rests on an iterative procedure whose complexity is image-dependent. This paper proposes an iterative-free fractal image decoding algorithm to reduce the decoding time. In the proposed method, under the encoder previously with the same codebook image as an initial image to be used at the decoder, the fractal coefficients are obtained through calculating the similarity between the codebook image and an input image to be encoded. As the decoding process can be completed with received fractal coefficients and predefined initial image without repeated iterations, the decoding time could be remarkably reduced.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.1
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• pp.11-18
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• 2012

In this paper, an entropy constrained vector quantizer for high bit-rates is proposed. The sample-adaptive product quantizer (SAPQ), which is based on the product codebooks, is employed, and a design algorithm for the entropy constrained sample adaptive product quantizer (ECSAPQ) is proposed. The performance of the proposed ECSAPQ is better than the case of the entropy constrained vector quantizer by 0.5dB. It is also shown that the ECSAPQ distortion curve, which is based on the scalar quantizer, is lower than the high-rate theoretical curve of the entropy constrained scalar quantizer, where the theoretical curve have 1.53dB difference from Shannon's lower bound.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.10A
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• pp.1159-1166
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• 2004

This paper follows up the previous work on the linearly constrained, modified minimum mean-squared error(MMSE) detection for direct-sequence code-division multiple-access DS-CDMA) systems in fading channels. We find a condition to avoid the breakdown of joint modified MMSE detection and pilot symbol-aided channel estimation (PSACE). The linearly constrained, modified MMSE solution is theoretically shown to be robust against time variations in Rayleigh fading channels. This fact is consistent with the simulation results. We also show that under some conditions the linearly constrained, modified MMSE detection maximizes the output signal-to-interference-plus-noise ratio.(SINR)

• The Korean Journal of Financial Management
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• v.16 no.2
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• pp.91-118
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• 1999

본(本) 연구(硏究)는 기업(企業)의 소유구조(所有構造)와 기업가치(企業價値) 사이의 관계를 분석하여 횡단면(橫斷面) 요인(要因)과 시계열(時系列) 요인(要因)을 결합하는 이론적(理論的) 모형(模型)을 제시하며, 또한 제시된 모형(模型)을 한국증권시장(韓國證券市場)의 자료(資料)를 이용하여 실증적(實證的)으로 분석하여 절충가설이 우리나라 기업에 적용될 수 있는지를 검토하였다. 본(本) 연구(硏究)에서는 기업가치(企業價値)를 나타내는 대용변수(代用變數)로 시장가치 대 장부가치비율을, 독립변수(獨立變數)로는 대주주 1인 지분율을 그리고 통제변수(統制變數)로는 광고비 정도, 기업규모, 재무레버리지, 30대 재벌 비재벌의 가변수(假變數)를 사용하였다. 실증분석 결과 본(本) 연구(硏究)에서 제시된 모형이 상당한 의미를 가지나, 모형(模型)의 설명력(說明力)은 비교적 낮아 본(本) 연구(硏究)에서 제시된 설명변수(說明變數)들이 자본구조(資本構造)의 변동(變動)을 8%정도 설명하고 있다. 또한 본(本) 연구(硏究)에서 제시된 독립변수 대주주 1인의 지분율과 이를 제곱한 것은 통계적으로 의미가 있는 변수가 되고 있다. 이는 대주주 1인의 지분율과 기업가치(企業價値) 사이에는 곡선관계(曲線關係)가 존재한다는 절충가설(折衷假說)을 지지하는 강력한 증거이다. 그리고 본(本) 연구(硏究)에서 제시된 통제변수(統制變數)인 광고비 정도, 기업규모, 재무레버리지 그리고 30대 재벌 비재벌 가변수(假變數) 등은 기업가치(機業價値)를 결정하는 통계적인 의미를 갖는 변수로 밝혀졌으며 회귀계수(回歸係數)의 부호도 기대하였던 바와 일치하고 있다.