• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.647-652
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• 2016

To reduce drag force at supersonic speeds, sharp leading edge is hugely efficient. It is, however, incompatible with leading edge shape to have fine aerodynamic characteristics at subsonic and transonic speeds. It is critical to reduce drag force for enhanced cruise performance and higher efficiency. An air superiority fighter, however, required to have high maneuverability for survivability, and sharp leading edge is not proper. Consequently, variable leading edge is demanded to reduce drag force significantly at supersonic speeds for cruise performance. Leading edge altering system is constructed with rigid material to improve possibility of realization, and minimized movement of its components in altering for reduce effects on flight. It is compared with bi-convex airfoil and NACA 65-006 airfoil, which have comparable maximum thickness. At Mach number 1.7 and zero angle of attack, supersonic mode of designed airfoil indicates approximately 17% higher drag coefficient than the bi-convex airfoil indicates, it is, however, 23% lower than the NACA 65-006 indicates. Also, subsonic mode of the designed airfoil shows fine aerodynamic characteristics in comparison with NACA 65-006 airfoil in subsonic and transonic speed range. In this regard, design of the airfoil achieved the object of this study satisfactorily.

• Journal of KIISE:Software and Applications
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• v.29 no.11
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• pp.809-817
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• 2002

This paper describes a new face detection method that is a pre-processing algorithm for on-line face recognition. To complement the weakness of using only edge or rotor features from previous face detection method, we propose the two types of face detection method. The one is a combined method with edge and color features and the other is a center area color sampling method. To prevent connecting the people's face area and the background area, which have same colors, we propose a new adaptive edge detection algorithm firstly. The adaptive edge detection algorithm is robust to illumination variance so that it extracts lots of edges and breakouts edges steadily in border between background and face areas. Because of strong edge detection, face area appears one or multi regions. We can merge these isolated regions using color information and get the final face area as a MBR (Minimum Bounding Rectangle) form. If the size of final face area is under or upper threshold, color sampling method in center area from input image is used to detect new face area. To evaluate the proposed method, we have experimented with 2,100 face images. A high face detection rate of 96.3% has been obtained.

• Proceedings of the IEEK Conference
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• 2001.06d
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• pp.199-202
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• 2001

A current TV-OUT format is quite different from that of HDTY or PC monitor in encoding techniques. In other words, a conventional analog TV uses interlaced display while HDTV or PC monitor uses Non-interlaced / Progressive-scanned display. In order to encode image signals coming from devices that takes interlaced display format for progressive scanned display, a hardware logic in which scanning and interpolation algorithms are implemented is necessary. The ELA (Edge-Based Line Average) algorithm have been widely used because it provided good characteristics. In this study, the ADI(Adaptive De-interlacing Interpolation) algorithm using to improve the algorithm which shows low quality in vertical edge detections and low efficiency of horizontal edge lines. With the De-interlacing ASIC chip that converts the interlaced Digital YUV to De-interlaced Digital RGB is designed. The VHDL is used for chip design.

• Journal of Information Processing Systems
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• v.15 no.1
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• pp.7-21
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• 2019

In order to improve the edge segmentation effect of the level set image segmentation and avoid the influence of the initial contour on the level set method, a saliency level set image segmentation model based on local Renyi entropy is proposed. Firstly, the saliency map of the original image is extracted by using saliency detection algorithm. And the outline of the saliency map can be used to initialize the level set. Secondly, the local energy and edge energy of the image are obtained by using local Renyi entropy and Canny operator respectively. At the same time, new adaptive weight coefficient and boundary indication function are constructed. Finally, the local binary fitting energy model (LBF) as an external energy term is introduced. In this paper, the contrast experiments are implemented in different image database. The robustness of the proposed model for segmentation of images with intensity inhomogeneity and complicated edges is verified.

• Journal of information and communication convergence engineering
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• v.20 no.3
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• pp.195-203
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• 2022

Noise generated during image acquisition and transmission can negatively impact the results of image processing applications, and noise removal is typically a part of image preprocessing. Denoising techniques combined with nonlocal techniques have received significant attention in recent years, owing to the development of sophisticated hardware and image processing algorithms, much attention has been paid to; however, this approach is relatively poor for edge preservation of fine image details. To address this limitation, the current study combined a steering kernel technique with adaptive masks that can adjust the size according to the noise intensity of an image. The algorithm sets the steering weight based on a similarity comparison, allowing it to respond to edge components more effectively. The proposed algorithm was compared with existing denoising algorithms using quantitative evaluation and enlarged images. The proposed algorithm exhibited good general denoising performance and better performance in edge area processing than existing non-local techniques.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1984.10a
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• pp.88-91
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• 1984

In component coding, it si well known that a Luminance edge provides better masking of the noise added to chrominance signals. So we propose an adapive DPCM coding system which provides good performance in chromainance signals by using the effect of this masking.

• Proceedings of the IEEK Conference
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• 2000.11d
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• pp.139-142
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• 2000

In this paper, the ADI (Adaptive De-interlacing) algorithm is proposed, which improves visually and subjectively horizontal and vertical edges of the image processed by the ELA(Edge Line-based Average) method. This paper also proposes a VLSI architecture for the proposed algorithm and designed the architecture through the full custom CMOS layout process. The proposed algorithm is verified using C and Matlab and implemented using 0.6$\mu\textrm{m}$ 2-poly 3-metal CMOS standard libraries. For the circuit and logic simulation, Cadence tool is used.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.2
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• pp.114-125
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• 1998

In this study, for the first time, we propose the ADI(Adaptive De-Interlacing) algorithm, which improves visually and subjectively, horizontal and vertical edges on the image processed by the ELA (Edge Based Line Average) method. The proposed ADI algorithm enlargesthe window size to 5*3 in order to utilize the feature of the continuity of edges, and the adaptive interpolator is employed to decide adaptiely horizontal, diagonal, and vertical edges. Based on the results of the compter simulation, it is confimed that the new ADI algorithm improve the PSNR by 0.5dB in the Lena image with 512*512 size and by 0.4dB in the sequence image of a salesman, respectively. For the horizontal and vertial edges on the still and salesman sequence images, the proposed ADI algorithm has better visulal improvement than the conventional ELA algorithm.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.3
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• pp.669-673
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• 2010

This paper proposes a new active noise control (ANC) system for canceling broadband noise. The proposed ANC system is designed based on the multiband-structured delayless subband adaptive filter (MDSAF), which has advantages of fast-convergence speed and higher noise reduction performance by eliminating the aliasing and band-edge effects caused by band-partitioning. The simulation results show that the proposed ANC system has faster convergence speed as compared to the conventional ANC systems and effectively reduces the wideband noise.

• Journal of Korea Multimedia Society
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• v.8 no.6
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• pp.783-789
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• 2005

This paper is proposed a watermarking technique for copyright protection of multimedia contents. We proposed adaptive watermark detection algorithm using stochastic perceptual model and statistical decision method in DMWT(discrete multi wavelet transform) domain. The stochastic perceptual model calculates NVF(noise visibility function) based on statistical characteristic in the DMWT. Watermark detection algorithm used the likelihood ratio depend on Bayes' decision theory by reliable detection measure and Neyman-Pearson criterion. To reduce visual artifact of image, in this paper, adaptively decide the embedding number of watermark based on DMWT, and then the watermark embedding strength differently at edge and texture region and flat region embedded when watermark embedding minimize distortion of image. In experiment results, the proposed statistical decision method based on multiwavelet domain could decide watermark detection.