• 한국음향학회:학술대회논문집
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• 한국음향학회 2002년도 하계학술발표대회 논문집 제21권 1호
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• pp.331-334
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• 2002

의사잡음 시퀀스를 이용한 대역확산 기반의 오디오 워터마킹은 들리지 않으면서도 강인한 워터마크를 만들기 위해 심리음향모델이나 고정필터를 사용하여 의사잡음 시퀀스를 변형시킨다. 그런데, 이러한 방법을 이용하여 스펙트럼 변형된 의사잡음은 고주파 영역에 대부분의 에너지를 갖게 되므로 인위적으로 오디오 신호의 고주파 영역을 잘라내는 공격에 취약하다는 단점이 있다. 본 논문에서는 이러한 단점을 보안하고 강인성 및 잡음의 최소화를 위하여 중간값의 성질을 이용하여 의사잡음을 변형 후 삽입하는 워터마킹 시스템을 제안한다. 중간값 성질을 이용하여 변형한 의사잡음은 원 오디오 신호와의 상관성이 높으며 전주파수 대역에 고르게 분포하는 성질이 있으므로 고주파 영역의 공격에 강인하다. 제안 방법은 의사잡음의 고유성질을 최대로 살린 방법으로 각종 오디오 부호화, 부가잡음, 다운/업 샘플링, 채널변경, 진폭 공격과 같은 다양한 공격에도 워터마크 신호의 검출이 가능하다.

• Journal of applied mathematics & informatics
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• 제27권5_6호
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• pp.1405-1410
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• 2009

A tripartite $\gamma$-digraph is an orientation of a tripartite multigraph that is without loops and contains at most $\gamma$ edges between any pair of vertices from distinct parts. In this paper, we obtain necessary and sufficient conditions for sequences of non-negative integers in non-decreasing order to be the sequences of numbers, called marks (or $\gamma$-scores), attached to the vertices of a tripartite $\gamma$-digraph.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2570-2575
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• 2003

Monitoring a power transmission line is significant for power electric companies. In this paper, we propose a new method for detecting an fault point of power transmission line by use of M-sequence correlation technique. In this method, detecting signal is used as one or plural M-sequences ( same characteristic polynomial, including normal and reverse mark, synchronized ). In receiving point, we make same sequence with the input one and take crosscorrelation function between M-sequence and the received signal. We can see transfer fanctions of plural paths between inputs and a output taps separated from different of delay times on the crosscorrelation function, and from these transfer fanctions, so we compare them when fault occurred with in usual.

• ETRI Journal
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• 제24권5호
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• pp.401-404
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• 2002

In this paper, we propose a non-blind watermarking method that embeds a pseudo-random sequence (watermarks) into wavelet DC components. The DC area is not suitable for embedding because of severe visual degradation. We overcome the degradation problem by embedding watermarks into visually insensitive locations. We compare our experimental results with respect to JPEG compression with Cox’s popular correlation-based method. We also compare the robustness of our technique with other methods registered in CheckMark. This study reveals that the proposed method simultaneously provides good fidelity in quality as well as robustness against external attacks.

• 대한인간공학회지
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• 제26권4호
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• pp.143-146
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• 2007

Due to the expansion of cities and the increasing number of large-scale and complex public spaces, there is an increase in public signage. Moreover, the information described on these signs tends to be diverse and complicated. Complex signs that contain multiple destinations or other information must be considered to determine not only the proper size, color, etc. but also the most effective arrangement of design elements. In the previous research, the cognitive utility of complex public signs was estimated using computer simulation software. In the current research, we focused on the objective estimation of the effectiveness of the results obtained in the previous research utilizing an eye mark recording system. Two cognitive engineering experiments clarified five points for improvement in the usability of complex signs, as follows: 1) Parallel construction of characters and pictograms is more efficient. 2) Grouping elements result in rapid recognition of information chunks. 3) Visual characters and pictograms are effective, along with proper density of information. 4) Specific arrangement of sign arrows is effective. 5) Figures on signs influence the sequence of information searches.

• 정보처리학회논문지B
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• 제10B권5호
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• pp.479-484
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• 2003

대부분의 워터마킹 기법은 공격에 대한 강인성과 비가시성을 통시에 만족시키기 위하여 중간주파수 영역에 워터마크를 삽입하는데 반해, 본 논문에서는 웨이블릿 분해된 영상의 저주파영역에 워터마크열, (-1, +1), 을 비가시적으로 삽입하는 블라인드 워터마킹 기법을 소개한다. 워터마크를 삽입하는 위치는 키에 의해 랜덤하게 선택되며, 화진열화를 크게 일으키는 계수에 대해서는 워터마크 삽입을 생략한다. 본 방식은 추출된 비터마크열의 상관도 계산에 의해 워터마크의 유무를 판정하므로 워터마크열의 일부가 삽입되지 않더라도 워터마크의 판정에는 무리가 없음을 보인다. 제안하는 방식의 성능은 ChechMark [1]의 벤치마킹 툴을 통하여 검증하였으며 [1]에 등록되어 있는 다른 방식들과 비교하였다.

• Journal of Microbiology and Biotechnology
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• 제9권5호
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• pp.576-581
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• 1999

Effects of signal sequences, protein sizes and dissolved oxygen on the secretion of human lysozyme from a recombinant yeast were experimentally characterized. The systems consisted of Saccharomyces cerevisiae host SEY2102 that was transformed with two different plasmids. These plasmids were identical with an exception to the plasmid pMC614, which contained the native yeast MFα1 sequence and the plasmid pMC632 with the non-native rat α-amylase signal sequence. The expression of human lysozyme was controlled by the ADHI promoter. The native yeast MFαl signal sequence was more efficient than the non-native rat α-amylase signal sequence in directing the secretion of human lysozyme. Lysozyme secreted with the α-amylase signal was retained inside the cells and released to the medium very slowly, thereby causing a lower cell growth rate and a decreased product secretion rate. Lysozyme was secreted more efficiently than invertase, which is an order of magnitude bigger in molecular size compared to lysozyme, which was under the direction of the MFαl signal sequence, suggesting that protein sizes may affect the secretion efficiency. When expressed in anaerobic conditions in the medium where the ADHI promoter was derepressed, the amount of lysozyme secreted was about twice higher than that of the aerobic culture. However, the secretion rates were identical. This result showed that the dissolved oxygen level may affect the efficiency of protein secretion only, and not the secretion rate of the product protein.

• 농업과학연구
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• 제38권1호
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• pp.11-16
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• 2011

In this study, we report the generation and analysis of a total of 1,211 expressed sequence tags (ESTs) from Pinus koraiensis. A cDNA library was generated from the young leaf tissue and a total of 1,211 cDNA were partially sequenced. EST and unigene sequence quality were determined by computational filtering, manual review, and BLAST analyses. In all, 857 ESTs were acquired after the removal of the vector sequence and filtering over a minimum length 50 nucleotides. A total of 411 unigene, consisting of 89 contigs and 322 singletons, was identified after assembling. Also, we identified 77 new microsatellite-containing sequences from the unigenes and classified the structure according to their repeat unit. According to homology search with BLASTX against the NCBI database, 63.1% of ESTs were homologous with known function and 22.2% of ESTs were matched with putative or unknown function. The remaining 14.6% of ESTs showed no significant similarity to any protein sequences found in the public database. Gene ontology (GO) classification showed that the most abundant GO terms were transport, nucleotide binding, plastid, in terms biological process, molecular function and cellular component, respectively. The sequence data will be used to characterize potential roles of new genes in Pinus and provided for the useful tools as a genetic resource.

• 한국콘텐츠학회논문지
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• 제11권5호
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• pp.481-488
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• 2011

인간은 살아가면서 필요에 의해 많은 문서를 작성한다. 일반적으로 문서란 쌍방 간의 약속인 동시에 거래의 신용에 대한 법률적 기능을 가진다. 문서작성은 양자 간의 동의하에 이루어져야 하며, 문서작성에 대한 투명성을 확보할 때 문서의 진성 성립이 이루어진다. 그렇기 때문에 문서작성 과정에 대한 선후관계 분석은 문서감정에 있어 매우 중요하다. 본 연구에서는 지워진 연필과 남아 있는 볼펜과의 선후관계를 밝혀 보험가입서 작성의 상호동의 유무를 판단할 수 있는 방법을 제안하고자 한다. 이 방법은 연필의 탄소성분이 볼펜 하단에 존재하는가를 적외선사진을 통해 분석하고 있다. 볼펜 하단에 연필이 있으면 적외선을 흡수하여 진한 농도로 기록되며, 볼펜 상단에 연필을 작성한 것이라면 이미 연필 성분이 많이 지워졌기 때문에 적외선 사진에 별다른 반응을 보이지 않게 된다. 이 방법은 비교적 간단한 적외선 촬영 시스템을 사용하기에 규모가 작은 사설감정소 등에서 많은 도움이 될 것이다.

• 대한전기학회논문지:시스템및제어부문D
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• 제51권3호
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• pp.108-111
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• 2002

This paper proposes an new water mark embedding and extraction technique which extends the direct sequence spread spectrum technique. The proposed technique approximates the complexity of image and block in spatial domain using Laplacian filtering and watermark is adaptively embedded in the mid-frequency DCT components. Local parity bits are attached to higher-frequency DCT components and they are used to detect extraction errors and correct those errors. In extraction process the proposed method boosts the higher frequency components of image and extracts the watermark by demodulation and this information is verified and adjusted by parity bits. Experimental results show it is invisible and robust to several external attacks.