• 전자공학회논문지 IE
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• v.43 no.4
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• pp.37-42
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• 2006

This paper proposes a adaptive video watermarking algorithm according to bitrate and motion vector size in MPEG2 system. The watermark strength in the I-frames is adapted for quantization step size and the strength in the P-B-frames is adapted for quantization step size and motion vector of macroblock to make the watermark more robust against the accompanying degradation due to aggressively compression. A realtime watermark extraction is done directly in the DCT domain during MPEG decoding without full decoding of MPEG video. The experimental simulations show that the video quality results almost invisible difference between the watermarked frames and the original frames and the watermark is resistant to frame dropping, MPEG compression, GoP conversion and low pass filter attacks.

• The Korean Journal of Applied Statistics
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• v.24 no.2
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• pp.373-381
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• 2011

This paper discusses how to get the sums of squares due to treatment factors when Type I Analysis is used by projections for the analysis of data under the assumption of a two-way ANOVA model. The suggested method does not need to calculate the residual sums of squares for the calculation of sums of squares. There-fore, the calculation is easier and faster than classical ANOVA methods. It also discusses how eigenvectors and eigenvalues of the projection matrices can be used to get the calculation of sums of squares. An example is given to illustrate the calculation procedure by projections for unbalanced data.

• Proceedings of the KIEE Conference
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• 1984.07a
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• pp.13-15
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• 1984

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.531-534
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• 1999

벡터제어기법은 유도전동기의 무부하 시험 및 구속시험 등을 통하여 구한 고정자 및 회전자 상수를 이용한 전동기의 수학적 모델을 기초로 하여 이루어진다. 따라서 유도전동기의 수학적 모델을 구성하는 고정자 및 회전자 상수의 정확성은 곧 벡터제어의 성능과도 직결된다. 하지만, 온도 상승 등의 영향으로 회전자 저항값은 정상치보다 최대 80∼100%까지 상승 할 수 있으며, 이는 벡터제어의 특성을 저하시키는 요인이 된다. 따라서, 본 연구에서는 회전자 저항을 이용하는 자속 PI제어부를 회전자 저항을 사용하지 않는 자속 퍼지제어부로 대체하고 측정한 3상 전류를 이용하여 회전자 저항값의 변화를 실시간으로 추정·보상하는 퍼지추론기를 구성하므로써 회전자 저항의 변화에도 최적의 효율 및 성능을 가지는 보완된 벡터 제어 기법을 개발하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.13 no.4
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• pp.302-308
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• 1988

The paper describes a very simple algorithm for reducing the encoding complexity of vector quantization(VQ), exploiting the feature of a vector currently being encoded. A proposed VQ of 16(=4x4) vector dimension shows a slight performance degradation of about 0.1-1.9dB, however, with only 16-32 among 256 codeword searches, i.e., with just 1/16-1/8 search complexity compared to a full-search VQ. And the proposed VQ scheme is also compared to outperform tree-search VQ with regard to their SNR performance and memory requirement.

• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.144-149
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• 1996

To develope the baculovirus expression vector system (BEVS) using Spodoptera exigua nuclear polyhedrosis virus (SeNPV), we characterized the polyhedrin of SeNPV. The SeNPV polyhedra was irregular and composed of the major protein molecular weight of 30 kDa determined by electronmicroscopy and SDS-AGE analysis, respectively. The nucleotid suquences of 876 bases including the coding region of polyhedrin gene was determined and it was revealed that the polyhedrin gene is located within Xho I 3.0Kb and Nco I 6.0 Kb by Southern blot analysis, respectively. Also, the Xho I 3.0 Kb and the Nco I 6.0 Kb fragments were cloned and restriction enzyme map of these clones were determined.

• Journal of Korea Multimedia Society
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• v.10 no.11
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• pp.1427-1438
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• 2007

Video watermarking technologies are classified into types of four kinds. The first type is to embed the watermark into a raw video signal and to code the watermarked video signal. Most of video watermarking technologies fall into the category of this type. The second type is to apply watermarking to the coding process, such as block DCT and quantization. The third is to directly embed the watermark into the compressed bitstream itself. Generally, it is referred as labelling rather than watermarking. Finally, the fourth is to embed the water mark into MPEG motion vector. This type has the difficulty in real-time process because of the high complexity and has the blocking effects because of DCT-based on coder. In this paper, we proposed the digital video watermarking that embed the watermark in SPIHT video code for I-frame using motion vector analysis. This method can remove the blocking effect occurred at the DCT-based on coder and obtain video data that has progressive transmission property. The proposed method is to select the region for the watermark embedding in I frame using motion vector estimated from the previous P or B frame. And then, it is to perform DWT and embed the watermark based on HVS into the wavelet coefficients in the same subband of DWT as the motion vector direction. Finally, the watermarked video bitstream is obtained by the SPIHT coder. The experimental results verified that the proposed method has the invisibility from the objective and subjective image quality and the robustness against the various SPIHT compression and MPEG re-code.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1222-1228
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• 2006

In this paper, I propose a video watermaking method using adaptive threshold value and half-cell motion vector. Conventional method cause a lot of change of motion vectors and bring about a falling-off in invisibility, because it search embedding condition about whole macroblocks and watermarks are embedded in arbitrary motion vectors. Proposed method improve invisibility and decrease in number of change of motion vectors, because it create threshold value by using power of motion vector(PMV), and watermarks are embedded in motion vectors which greater than threshold value. Consequently, proposed method improve invisibility with on an average 5.4 dB ~9.3dB according to video bit-stream.

• Computational Structural Engineering
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• v.9 no.4
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• pp.219-228
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• 1996

A method used for measuring the stiffness of hinging reinforced concrete frame structures is developed. The so called Stiffness Measure Method is used to evaluate the tangent stiffness of hinge regions while the structure is responding in nonlinear ranges. Eigenvector methods for nonlinear response have not been especially popular because of the need for regenerating eigenvectors as the time history proceeds. In the present work the eigenvectors sets and corresponding nonlinear state variables, i. e., the tangent stiffnesses of the hinge regions, are stored. There is an expectation that previously generated eigenvectors can be reused as the analysis proceeds. The stiffness measure is used to compare the current tangent stiffnesses of hinge regions with those of previously stored eigenvectors sets. Since eigenvector calculations are diminished the method is effective in reducing computational effort for reinforced concrete frame structures subjected to strong ground motions.

• Honam Mathematical Journal
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• v.3 no.1
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• pp.41-60
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• 1981

다양체(多樣體)의 연구(硏究)에서 벡터속(束)의 개념(慨念)은 불가결(不可缺)하며 벡터속(束)의 연구(硏究)에는 엽층구조(葉層構造)의 연구(硏究)가 중요(重要)하다. 본(本) 논문(論文)은 권(圈) $\varrho$(M)의 응사보편공간(凝似普遍空間)에 관한 연구(硏究)(정리(定理) 4.8)로서 R. Bott의 엽층구조(葉層構造)에 관한 연구(硏究)([1])에서 착상(着想)된 것이다. 제이(第二), 삼절(三節)은 제사절(第四節)을 위한 준비(準備)로서, 제이절(第二節)에서는 벡터속(束)및 접속(接續)에 관한 성질(性質)을 논하고, 제삼절(第三節)에서는 위상권(位相圈), 층(層), 엽층구조(葉層構造) 및 $\Gamma_{q}$-cocycle 등에 관한 성질(性質)(명제(命題) 3.5, 3.7과 3.11)을 밝히고, 위상권(位相圈)의 구체적(具體的)인 예(例)(예(例)3.2, 3.3과 3.12)를 들었다. 제사절(第四節)에서는 $GL_{q}-cocycle$, 위상권(位相圈) $GL_{q}$, 집합(集合) $I_{so}(M_{k},\;GL_{q})$, $H^{1}(M_{k},\;GL_{q})$, $I_{so}(\varrho(M))$ 및 응사보편공간(凝似普遍空間)을 정의(定義)하고, 주정리(主定理) 4.8의 증명(證明)에 필요(必要)한 명제(命題)를 몇 개 기술(記述)하였다(명제(命題) 4.2, 4.5와 보제(補題) 4.9).