• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.460-460
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• 2006

• Journal of Korea Ship Safrty Technology Authority
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• s.23
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• pp.2-13
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• 2007

With the effectuation of the amendment of MARPOL 73/78 on 5 April 2005, enforcement regulations of Marine Pollution Prevention Act were revised in domestic on 12 March 2005 that double hull structure was required to the small single bottom oil tankers under DWT(deadweight tonnage) 500 ton for the protection of the marine pollution casualties. The objective of this study is to develop the double bottom structure of small oil tanker under DWT 500 ton with superior crashworthiness and to establish its suitable standard to double bottom structure. The promoting strategy of this R&D is classified into the crashworthy structural analysis of small oil tankers using LS/DYNA3D code and the examination of their damage stabilities according to tonnage. It could be thought that the desirable inner bottom height should be above the B/7.5 and its minimum height 0.65m for the domestic small oil tanker under DWT 500ton.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.6
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• pp.59-68
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• 2002

In this paper, we design the two-dimensional Discrete Wavelet Transform (2D DWT) filter that is widely used in various applications such as image compression because it has no blocking effects and relatively high compression rate. The filter that we used here is two-channel four-taps QMF(Quadrature Mirror Filter) Lattice filter with PR (Perfect Reconstruction) property. The proposed DWT architecture, with two consecutive inputs shows an efficient performance with a minimum of such hardware resources as multipliers, adders, and registers due to a simple scheduling. The proposed architecture was verified by the RTL simulation, and utilizes the hardware 100%. Our architecture shows a relatively high performance with a minimum hardware when compared with other approaches. An efficient memory mapping and address generation techniques are introduced and the fixed-point arithmetic analysis for minimizing the PSNR degradation due to quantization is discussed.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.5 s.305
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• pp.11-18
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• 2005

In this paper, we proposed a video watermarking algerian based on wavelet transform using statistical characteristic of video according to the energy distribution and the spread spectrum technique. In the proposed method, the original video is splitted by spatial difference metric and classified into the motion region and the motionless region according to the motion degree. The motion region is decomposed into 3-levels using 3D DWT and the motionless region is decomposed into 2-levels using 2D DWT The baseband of the wavelet-decomposed image is not utilized because of the image quality. So that the standard deviation of the highest subband coefficients except for the baseband is used to determine the threshold. Binary video watermarks preprocessed by the random permutation and the spread spectrum technique are embedded into selected coefficients. In computer experiments, the proposed algorithm was found to be more invisible and robust than the conventional algorithms.

• Journal of information and communication convergence engineering
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• v.12 no.3
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• pp.173-180
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• 2014

This paper investigates the robustness of watermarking techniques for stereo or multi-view images generated from texture and depth images. A three-dimensional (3D) warping technique is applied to texture and depth images to generate stereo or multi-view images for a 3D display. By using the 3D warping technique, in this paper, we developed watermarking techniques and evaluated the robustness of these techniques that can extract watermarks from texture images even when the viewpoints are moved. A depth image is used to generate a stereo image with the largest viewpoint difference to the left and right. The overlapping region in the stereo image that does not disappear after warping is then obtained, and DWT is applied to this region to embed a watermark in the LL sub-band. The proposed watermarking techniques were found to yield bit error rates of about 3%-16% when they were applied to stereo images generated from texture and depth images. Furthermore, the results showed that the copyright could be seen when the extracted watermark was visually confirmed.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.997-998
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• 2008

In this paper, we proposed a reduced memory overdrive architecture. Proposed overdrive architecture consists of 2D-DWT filter, BLI and Color Conversion block. For Frame Memory reduction we eliminated HH data in DWT-IDWT process and converted color space RGB into YCbCr. Consequently, we reduced Frame Memory about 50%.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.11
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• pp.112-119
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• 1999

TMN5 has been used to evaluate the performance of H.263, the ITU-T/LBC standard of moving picture coding. As DCT is used as transform coding methods in TMN5, blocking effect exists seriously in reconstruction picture at low bit rate. In this pater, DWT is substituted for DCT and adaptive quantizer is designed while the structure of TMN5 is maintained to be excellent in the transplantation of conventional system. It has shown that average PSNR is reduced by 0.35dB in luminance but increased by 2dB in chrominance comparing with that of TMN5. As block effect is reduced in reconstruction picture, the subjective picture quality is better than that of TMN5. Picture drop is, also, reduced because much more frames are transmitted at same bit rate.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.392-397
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• 2000

An Interlaced 2D field images compression technique by Discrete Wavelet Transform is proposed. The result has a good image resolution and compression rate, PSNR, and reduces processing time of compression. PSNR depends on the exponential function corresponding to 2 power N has higher 30% than DCT. And It is easier to process the inter-frame and fast to work a second with each parallel field processing, and more be able to approximate a frame on the field.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2016.11a
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• pp.103-106
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• 2016

인터넷 사용의 발달로 디지털 미디어 영상에 대한 불법 복제, 불법 배포 등의 문제가 완연해짐에 따라 영상의 제작자의 소유권과 저작권을 보호할 수 있는 워터마크 기법이 많이 연구되고 있다. 워터마크 시스템은 워터마크 삽입 후, 삽입정보를 알 수 없어야하는 비가시성 특성과 여러 공격에도 훼손되지 않고 추출될 수 있는 강인함을 가지고 있어야 한다. 이에 본 논문은 이산 웨이블릿 변환(DWT)으로 생성되는 부대역의 점유 주파수대역 특성과 공격이 이 부대역들에 미치는 영향을 분석하고, 이를 사용하여 디지털 워터마킹을 수행하였을 때 추출률을 최고로 하기 위해서는 변환된 부대역이 특정 범위내의 해상도를 가져야 한다는 것을 보인다. 본 연구는 실험적 방법으로 모든 부분연구는 실험에 의해서 결정된다.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.8
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• pp.117-125
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• 2015

In this paper, we propose a classification algorithm based on the obtained EEG(Electroencephalogram) signal for the control of 'left' and 'right' turnings of which a driving system composed of EEG sensor, Labview, DAQ, Matlab and driving robot. The proposed algorithm uses features extracted from frequency band information obtained by DWT (Discrete Wavelet Transform) and selects features of high discrimination by using Fisher score. We, also propose the number of feature vectors for the best classification performance by using SVM(Support Vector Machine) classifier and propose a decision pending algorithm based on MLD (Maximum Likelihood Decision) to prevent malfunction due to misclassification. The selected four feature vectors for the proposed algorithm are the mean of absolute value of voltage and the standard deviation of d5(2-4Hz) and d2(16-32Hz) frequency bands of P8 channel according to the international standard electrode placement method. By using the SVM classifier, we obtained 98.75% accuracy and 1.25% error rate. Also, when we specify error probability of 70% for decision pending, we obtained 95.63% accuracy and 0% error rate by using the proposed decision pending algorithm.