• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.2
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• pp.41-52
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• 2011

It is important to reduce computational complexity of de-blocking filter for real-time implementation, because it accounts for a great part of total computational complexity of the decoder. Because there are a lot of conditional branches and memory accesses in a decoding loop, it is not easy to speed up the de-blocking filter. Therefore, this paper presents a new algorithm of de-blocking filter minimizing conditional branches and memory accesses. The proposed structure of de-blocking filter enables filter operation to parallelize by software pipelining. The proposed optimization method was implemented on a TMS320DM6467 EVM board and we achieved approximately 46% cycle reduction, compared with that of FFmpeg.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.285-293
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• 2014

Two-dimensional PDF417 bar code has a wide range of use and has a storage capacity to compress a large amount of data. With these characteristics, PDF417 has been used in various ways to prevent the forgery and alteration of important information in documents. On the other hand, previous decoding methods in PDF417 barcode are slow and inefficient because they simply employ the standard specifications of AIM (Association for Automatic Identification and Mobility). Therefore, this paper propose an efficient and fast algorithm of decoding PDF417 bar code. As a result, the proposed decoding algorithm will be more faster and efficient than previous methods.

• Journal of the Korean Chemical Society
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• v.33 no.6
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• pp.657-661
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• 1989

Symmetrical divinyl ketone or divinyl ${\alpha}$-diketone was synthesized in moderately good yields through palladium catalyzed carbonylative homocoupling reaction of vinylmercuric chlorides with carbon monoxide. In order to find out optimum synthetic reaction conditions, we examined the effect of catalysts, bases, solvents and reaction temperature when (E)-styrylmercuric chloride was used as a typical starting material. The best yield of divinyl ${\alpha}$-diketone was obtained in the reaction using 10 mol% of dichlorobis(triphenyl phosphine)palladium (II) as a catalyst, an equivalent of pyridine as a base, 10 mol% of iodine and acetonitrile at 50${\circ}$C under 10 atmospheric pressure of carbon monoxide. The yield of divinyl ${\alpha}$-diketone was decreased under atmospheric pressure of carbon monoxide.

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.522-529
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• 1989

Symmetrical divinyl ketones and divinyl ${\alpha}$-diketones were synthesized in moderately good yields through palladium catalyzed carbonylative homocoupling reaction of vinylic halides. Divinyl ${\alpha}$-diketones were obtained in the highest yield in the presence of 10 atm of carbon monoxide, using 2 mol% ligand added to palladium(II) acetate as catalyst and three equivalents of tributylamine as base in polar solvent at $100^{\circ}C$. Divinyl ketones were synthesized mainly under atmospheric pressure of carbon monoxide. The reaction was also proceeded to several other vinylic halides under the above reaction condition. Thus, divinyl ketones and divinyl ${\alpha}$-diketones were synthesized selectively as expected.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.17 no.2
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• pp.151-160
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• 2004

In the present study, Loop scheme is applied to generate smooth surfaces. To be consistent with the limit points of target surface, the initial sampling points are properly rearranged. The pointwise errors of curvature and position in the sequence of subdivision process are evaluated in the Loop subdivision scheme. A first-order shear deformable Loop subdivision triangular element which can handle transverse shear deformation of moderately thick shell are developed. The developed element is more general than the previous one based on classical shell theory, since the new one includes the effect of transverse shear deformation and has standard six degrees of freedom per node. The quartic box spline function is used as interpolation basis function. Numerical examples for the benchmark static shell problems are analyzed to assess the performance of the developed subdivision shell element and locking trouble.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.4
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• pp.699-706
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• 2008

H.264/AVC is a new international standard for the compression of video images, in which a deblocking filter has been adopted to remoye blocking artifacts. This paper proposes an efficient architecture of deblocking filter in H.264/AVC. By making good use of data dependence between neighboring $4{\times}4$ blocks, the memory sire is reduced and the throughput of the deblocking filter processing is increased. The designed deblocking filter further enhances the parallelism by simultaneously executing horizontal and vertical filtering within a macroblock in pipeline method and adopting overlap between macroblocks. The implementation result shows that the proposed architecture enhances the performance of deblocking filter processing from 1.75 to 4.23 times than that of the conventional deblocking filter. Hence the Proposed architecture of deblocking filter is able to perform real-time deblocking in high-resolution($2048{\times}1024$) video applications.

• Venture DIGEST
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• s.115
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• pp.21-21
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• 2008

정부가 국방 현대화 사업의 일환으로 추진하는 군 정보화 프로젝트는 건당 예산이 수십억에서 최고 수백억 원으로 어마어마하다. 유-디펜스연구소는 이같은 국방 분야 EA(군정보화 청사진)를 설계하는 군사전문 컨설팅회사로서 최근 군 전장관리 EA사업의 1단계 프로젝트를 수주했다. 경쟁사인 삼성SDS, LG EDS 등 거대 SI업체를 제치고 군 정보화 사업에서 다크호스로 떠오른 유-디펜스연구소를 찾아가 보았다.

• 정보화사회
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• s.117
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• pp.36-39
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• 1997

노트PC, 휴대전화, PHS등 정보통신 툴의 거의 대부분에 "액정 Flat-Display"가 사용되고 있다. 19세기에 발견되었고 금세기들어 이용법이 확립된 "액정"은 Flat-Display로서 오늘날 정보통신을 밑받침하는 하나의 요소가 되고 있다. 여기서는 "액정 디스프레이"를 비롯 일상 아무거리낌없이 쓰고 있는 정보통신 단말기등의 디스프레이를 통하여, 그 기술 개발과 풍요로운 정보사회와의 연결고리 나아가서 그 미래를 탐색해 본다.

• Digital Contents
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• no.5 s.144
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• pp.20-23
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• 2005

지난 5년간 영화‘디 워(D-War)’한편을 만들기 위해 절치부심해 온 영구아트무비의 심형래 사장. 5년 동안 절치부심했던 그가 야심작‘디 워’를 앞세워 세계 재패를 꿈꾸고 있다. 금세기의 대작으로 꼽히는‘반지의 제왕’을 넘어서겠다는 야심마저 품고 있는 심형래 사장과‘디 워’로 세상을 깜짝 놀래킬 준비를 하고 있는 영구아트무비 제작진들을 만났다.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.477-480
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• 2001

본 논문에서는 허프만 코딩의 기본 원리인 이진트리로부터 생성된 효율적인 일차원 검색테이블 구성과, 프로세싱 효율을 증가시키기 위한 수치연산 기법의 도입을 통하여 도출된 효율적인 허프만 디코딩 방법을 제시한다. 제안된 방법에서는 허프만 코드화 된 비트스트림으로부터 읽어 들인 비트 데이터를 직접 이진트리를 검색하기 위한 주소연산에 적용함으로써, 기존의 이진트리 검색을 위하여 수행되던 비교 및 분기문의 제거를 가능토록 하였다. 본 논문에서 제안하는 허프만 디코딩 기법은 기존의 비교 및 분기구분에 의하여 수행되던 허프만 디코딩 기법대비 30%이상의 검색속도 증가 및 이진트리 방식의 검색을 수행하기 위하여 필요로 하는 검색테이블에서 존재하던 데이터 및 노드간의 연결주소를 저장하기 위하여 사용되던 메모리 공간을 효율적으로 제거할 수 있는 일차원 검색테이블을 구성함으최써, 기존 방법대비 1/3의 메모리 공간만을 사용하도록 하였다. 제안된 허프만 디코딩 기법의 성능평가를 위하여 MPEG-2 AAC의 허프만 디코더에 적용한 결과 기존의 순차검색방법에 의한 디코딩 기법대비 198%의 성능향상 결과를 확인할 수 있었다.