• Title/Summary/Keyword: Visibility Function

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Implementation of closed caption service S/W module on DTV receiver (DTV 수신기의 자막방송 S/W 모듈의 구현)

  • Kim Sun-Gwon;No Seung-Yong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.1
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    • pp.69-76
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    • 2004
  • Recently, The development of DTV receiver and the need of its additional services have been increased vastly. In this paper, we implement new closed caption engine for the deaf and hard of hearing person and languages studying on DTV receiver, The specification of domestic closed caption is almost adopted that of EIA-608A. In this paper, with fully following the specification, we will present how to implement functions of closed caption with new algorithm. the function includes paint-on, Pop-on, roll-up/down, etc. experimental results show that the proposed technique provides satisfactory performance on DTV receiver.

Numerical Study on the Improvement of the Motion Performance of a Light Buoy

  • Son, Bo-Hun;Jeong, Se-Min
    • Journal of Ocean Engineering and Technology
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    • v.34 no.2
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    • pp.66-76
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    • 2020
  • A light buoy is equipped with lighting functions and navigation signs. Its shape and colors indicate the route to vessels sailing nearby in the daytime, with its lights providing this information at night. It also plays a role in notifying the presence of obstacles such as reefs and shallows. When a light buoy operates in the ocean, the visibility and angle of light from the lantern installed on the buoy changes, which may cause them to function improperly. Therefore, it is necessary for the buoy to have stable and minimal motions under given environmental conditions, mainly waves. In this study, motion analyses for a newly developed lightweight light-buoy in waves were performed to predict the motion performance and determine the effect of the developed appendages for improving the motion performance. First, free decay tests, including benchmark cases, were performed using computational fluid dynamics (CFD) to estimate the viscous damping coefficients, which could not be obtained using potential-based simulations. A comparison was made of the results from potential-based simulations with and without considering viscous damping coefficients, which were estimated using CFD. It was confirmed that the pitch and heave motions of the buoy became smaller when the developed appendages were adopted.

Adaptive Digital Watermarking with Perceptually Tuned Characteristic Based on Wavelet Transform (웨이브릿 변환영역에서 지각적 동조특성을 갖는 적응적 디지털 워터마킹)

  • 김현천;장봉주;서용수;김종진
    • Journal of Korea Multimedia Society
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    • v.6 no.6
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    • pp.1008-1014
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    • 2003
  • In this paper, we propose the image retrieval method based on object regions using bidirectional round filter in the wavelet transform domain. A conventional method that includes unnecessary background information reduce retrieval efficiency, because of the extraction of feature vectors from the whole region of subband. On proposed method, it extracts accurate feature vectors and keep certainly retrieval efficiency in case of reduced feature vectors, because of the extraction of feature vectors from the only extracted object region. Furthermore, it improve retrieval efficiency by removing unnecessary background information. Consequently, the retrieval efficiency is improved with 2.5%∼5.5% values, which have a little chances to vary according to characteristics of image.

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Digital Video Contents Protection based on DRM (DRM 기반의 디지털 비디오 콘텐츠 보호)

  • Boo, Hee-Hyung;Lee, Wu-Ju;Bae, Ho-Young;Lee, Bae-Ho
    • Proceedings of the Korea Information Processing Society Conference
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    • 2005.05a
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    • pp.827-830
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    • 2005
  • 본 논문은 DRM(Digital Rights Management)의 핵심요소기술인 디지털 비디오 워터마킹 기술에서 암호화 기법을 함께 적용하여 저작권 판별 및 콘텐츠 보호의 두 가지 역할을 수행하는 시스템을 제안하고자 한다. 본 논문에서는 저작권 정보를 공개키 기반의 RSA 암호화 방법으로 암호문을 만든 후 이진화 과정을 수행하여 워터마크 키 정보를 생성하였고, 워터마킹 기법으로는 통계적 모델의 계산 속도가 빠른 NVF(Noise Visibility Function) 방식의 Adaptive Stationary GG(Generalized Gaussian) model[1]의 기법을 사용하였다. 암호문은 사용자 컨트롤러에서 제어가 가능하도록 하여 권한이 부여된 사용자만이 재생이 가능하도록 하였다. 본 논문의 구성은 2장에서 암호화 과정을 설명하고, 3장에서는 기존의 기법과는 다른 통계적 접근의 워터마킹 기법을 적용한 과정을 설명하며, 4장에서는 제안한 방법이 실제 환경에서의 실험 결과를 보여준다. 마지막으로 5장에서는 결론과 개선점을 바탕으로 향후 연구방향을 제시한다. 본 논문에서 제안한 방법은 미래사회 인터넷에서의 올바른 디지털 콘텐츠 사용 문화 정책에 큰 역할을 할 것으로 기대된다.

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Usefulness of Functional MRI for the study of concentration sheet (Functional MRI를 이용한 학습집중력 향상 시트 개발)

  • Kim, Chang-Gyu
    • Proceedings of the KAIS Fall Conference
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    • 2009.05a
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    • pp.13-17
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    • 2009
  • In this thesis, we made a sheet to improve the concentration of study. To demonstrate the improvement in the concentration of study, we obtained functional magnetic resonance imaging (fMRI), which has superior time resolution and measures brain noninvasively by using intrinsic contrast agent. As a result of Brainwave measurement, we could verify the blood flow's activate in the nearby frontal lobe related to memory process and noticeable ratio change in absolute alpha wave and beta wave after the analysis of Brainwave measurement. fMRI ascertains the physiological function of the brain and is being used to prevent the trouble medically that can be caused before and after the operation. For the visibility of cranial nerve network, many researches will be carried out to develope the product which is related to brain like concentration of study.

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Human Visual System based Automatic Underwater Image Enhancement in NSCT domain

  • Zhou, Yan;Li, Qingwu;Huo, Guanying
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.2
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    • pp.837-856
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    • 2016
  • Underwater image enhancement has received considerable attention in last decades, due to the nature of poor visibility and low contrast of underwater images. In this paper, we propose a new automatic underwater image enhancement algorithm, which combines nonsubsampled contourlet transform (NSCT) domain enhancement techniques with the mechanism of the human visual system (HVS). We apply the multiscale retinex algorithm based on the HVS into NSCT domain in order to eliminate the non-uniform illumination, and adopt the threshold denoising technique to suppress underwater noise. Our proposed algorithm incorporates the luminance masking and contrast masking characteristics of the HVS into NSCT domain to yield the new HVS-based NSCT. Moreover, we define two nonlinear mapping functions. The first one is used to manipulate the HVS-based NSCT contrast coefficients to enhance the edges. The second one is a gain function which modifies the lowpass subband coefficients to adjust the global dynamic range. As a result, our algorithm can achieve contrast enhancement, image denoising and edge sharpening automatically and simultaneously. Experimental results illustrate that our proposed algorithm has better enhancement performance than state-of-the-art algorithms both in subjective evaluation and quantitative assessment. In addition, our algorithm can automatically achieve underwater image enhancement without any parameter tuning.

Optimization of ship inner shell to improve the safety of seagoing transport ship

  • Yu, Yan-Yun;Lin, Yan
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.5 no.3
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    • pp.454-467
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    • 2013
  • A practical Ship Inner Shell Optimization Method (SISOM), the purpose of which is to improve the safety of the seagoing transport ship by decreasing the maximum Still Water Bending Moment (SWBM) of the hull girder under all typical loading conditions, is presented in this paper. The objective of SISOM is to make the maximum SWBM minimum, and the section areas of the inner shell are taken as optimization variables. The main requirements of the ship performances, such as cargo hold capacity, propeller and rudder immersion, bridge visibility, damage stability and prevention of pollution etc., are taken as constraints. The penalty function method is used in SISOM to change the above nonlinear constraint problem into an unconstrained one, which is then solved by applying the steepest descent method. After optimization, the optimal section area distribution of the inner shell is obtained, and the shape of inner shell is adjusted according to the optimal section area. SISOM is applied to a product oil tanker and a bulk carrier, and the maximum SWBM of the two ships is significantly decreased by changing the shape of inner shell plate slightly. The two examples prove that SISOM is highly efficient and valuable to engineering practice.

Content Adaptive Watermarkding Using a Stochastic Visual Model Based on Multiwavelet Transform

  • Kwon, Ki-Ryong;Kang, Kyun-Ho;Kwon, Seong-Geun;Moon, Kwang-Seok;Lee, Joon-Jae
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1511-1514
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    • 2002
  • This paper presents content adaptive image watermark embedding using stochastic visual model based on multiwavelet transform. To embedding watermark, the original image is decomposed into 4 levels using a discrete multiwavelet transform, then a watermark is embedded into the JND(just noticeable differences) of the image each subband. The perceptual model is applied with a stochastic approach fer watermark embedding. This is based on the computation of a NVF(noise visibility function) that have local image properties. The perceptual model with content adaptive watermarking algorithm embed at the texture and edge region for more strongly embedded watermark by the JND. This method uses stationary Generalized Gaussian model characteristic because watermark has noise properties. The experiment results of simulation of the proposed watermark embedding method using stochastic visual model based on multiwavelet transform techniques was found to be excellent invisibility and robustness.

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Proposal of safe fire escape system for the day-care center and the kindergarten (어린이집 및 유치원의 화재 대피용 안전 경로 시스템 제안)

  • Choi, Jun-Ho;Kwon, Mee-Rhan
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.6
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    • pp.297-301
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    • 2015
  • Day-care centers and kindergartens are increasing along with the damage caused by fire year after year. Infants and toddlers have a low response capability than adults to fire situations such as heavy smoke which causes less or zero visibility thus it is difficult in evacuation route during dangerous fire situations. Because of these circumstances, teachers need to build a safe pathway signage system along with the usual fire safety training needs of infants and children. In this paper, we propose a system for fire escape which marks the escape routes and are automatically implemented through the push function that smartphone recognizes during the real-time fire situation, and establish a system that verifies its authenticity.

Modeling for Evolution of a 3-dimensional Structure on Semiconductor Substrate (반도체 기판 위의 3차원 구조에 대한 형상 진화 모델링 연구)

  • Jung, Hyun-Su;Won, Tae-Young
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.37 no.12
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    • pp.24-28
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    • 2000
  • This paper reports a new calculation method of three dimensional deposeition rate by level set method. To model an advancement of the surface efficiently, we have developed a new iteration method to re-initialize the level set function. For calculating etching and deposition rate by direct flow, we have developed a visibility test module and a refraction and re-sputtering model. Sputter deposition rate with shadow effect and surface refraction is calculated. We report that difference of profiles in cases that sticking coefficient are 1.0 and 0.3. We report that the difference of the deposition rate on bottom of the hole is caused by a difference of visible angle by the shadowing effect.

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