• Title/Summary/Keyword: Reconstruct

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The Applicability of Stable Isotope Analyses on Sediments to Reconstruct Korean Paleoclimate (우리나라의 고기후 복원을 위한 습지 퇴적물의 안정동위원소 분석 가능성 연구)

  • Park, Jung-Jae
    • Journal of the Korean Geographical Society
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    • v.43 no.4
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    • pp.477-494
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    • 2008
  • Stable isotope analyses on lake or wetland sediments are useful to reconstruct paleoclimate. Organic and inorganic carbonates obtained from lake sediment are isotopically analyzed to get oxygen and carbon isotopic ratios. Oxygen isotope ratios can be used to quantitatively and qualitatively reconstruct paleo-temperature or humidity while carbon isotope ratios be used to reveal environmental changes around the lake or human impacts on the area. Peat mosses in peat bogs are nice samples for the carbon isotope analysis, which derives paleo-temperature and paleo-atmospheric $CO_2$ changes. In coastal area, the reconstruction of past sea-level is possible because terrestrial originated organic matter is carbon isotopically different from marine originated organic matter. Also, scientists can do research on Asian Monsoon based on the fact that $\delta^{13}C$ of C3 plants and C4 plants are consistently different each other and that they are distributed differently with respect to salinity. In Korea, paleoenvironmental studies using stable isotopes are not popular yet because of low academic interests on the methodology and difficulties of obtaining proper sediment samples. Interesting results can be produced to answer paleoenvironmental questions of Korea if scientists isotopically analyze sediment cores from a paleo-lake such as Hanon in Jeju island, peat bogs such as Mujechi-Neup and Yong-Neup, and coastal wetlands.

Three-Dimensional Image Display System using Stereogram and Holographic Optical Memory Techniques (스테레오그램과 홀로그래픽 광 메모리 기술을 이용한 3차원 영상 표현 시스템)

  • 김철수;김수중
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.6B
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    • pp.638-644
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    • 2002
  • In this paper, we implemented a three dimensional image display system using stereogram and holographic optical memory techniques which can store many images and reconstruct them automatically. In this system, to store and reconstruct stereo images, incident angle of reference beam must be controlled in real time, so we used BPH(binary phase hologram) and LCD(liquid crystal display) for controlling reference beam. The reference beams are acquired by Fourier transform of BPHs which designed with SA(simulated annealing)algorithm, and the BPHs are represented on the LCD with the 0.05 seconds time interval using application software for reconstructing the stereo images. And input images are represented on the LCD without polarizer/analyzer for maintaining uniform beam intensities regardless of the brightness of input images. The input images and BPHs are edited using application software(Photoshop) with having the same recording scheduled time interval in storing. The reconstructed stereo images are acquired by capturing the output images with CCD camera at the behind of the analyzer which transforms phase information into brightness information of images. In output plane, we used a LCD shutter that is synchronized to a monitor that display alternate left and right eye images for depth perception. We demonstrated optical experiment which store and reconstruct four stereo images in BaTiO$_3$ repeatedly using the proposed holographic optical memory techniques.

Reconstruction of the Defect in Perineum using Local perforator based flap (천공지 기저 국소 피판을 이용한 회음부 결손의 재건)

  • Lee, Joo Hong;Yun, In Sik;Lee, Dong Won;Lee, Won Jai;Rah, Dong Kyun
    • Archives of Plastic Surgery
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    • v.36 no.5
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    • pp.565-570
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    • 2009
  • Purpose: Numerous techniques have been introduced to reconstruct the perineal area in order to preserve function of both the recipient and the donor site while satisfying aesthetic results. There are several advantages of using the pudendal aretery perforator based flap in that it provides thin coverage of defect area and a relatively excellent circulation through perforators. The perineal region can be divided into two areas : the urogenital triangle and the anal triangle. Since each area differs in structure and function so does its reconstructive plan. The authors of this article report clinical results obtained from pudendal artery perforator based reconstructed cases according to each differrent triangles. Methods: A total of 15 patients who underwent perineal reconstruction were enrolled in our study between the year 2002 and 2006. There were 4 cases of vaginal cancer, 4 cases of extramammary Paget's disease, 1 case of rectovaginal fistula in females and 2 cases of Paget's disease and 4 cases of Fournier's gangrene in male cases. The follow up period was on average 6 month. In female, superfical pudendal artery perforator based local flap were used to reconstruct the urogenital triangle defects, while internal pudendal artery perfoator based local flaps were used to reconstruct the anal traingle defects. In males the gracilis myocutaneous flap and internal pudendal artery perforator based local flaps were used in reconstruction of the scrotum and perineal defect. Result: In females, there was 1 case of partial flap necorsis that employed the superficial pudendal artery perforator but secondary repair through the internal pudendal artery perforator based local flap was done. In addition, there were 4 wound dehiscence cases in females and 2 cases in males. Conclusion: We believe that a better aesthetic and functional outcome can be achieved in perineal reconstruction if discrete surgical planning is carried out systematically categorizing the choice of flap employed acccording to distinct anatomical regions : the urogenital and the anal triangle.

Seasonality Study of Shellfish Gathering using Oxygen Isotope Analysis (산소동위원소 분석을 이용한 조개채집의 계절성 연구)

  • 안덕임;이인성
    • The Korean Journal of Malacology
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    • v.12 no.2
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    • pp.105-108
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    • 1996
  • In archaeology, oxygen isotope analysis using marine shells has been used to reconstruct past environment and determine the season of shellfish-gathering activities in the past. Modern oysters(Crassostrea gigas) from Solsum ao the mouth of Chonsu Bay were anayzed to examine the potential of the species for determining seasonality by oxygin isotope analysis. As a result, it appears that the species can be used for this purpose.

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Critical Review of Reconstruction Filters for Convolution Algorithm

  • Ra, Jong-Beom
    • Proceedings of the KIEE Conference
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    • 1979.08a
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    • pp.155-157
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    • 1979
  • The Fourier convolution algorithms are used to reconstruct a 3-D density function from the projection data sets. The convolved data are then back projected to obtain a density function. There are several choices of the weighting function for the design of the reconstruction(deblurring) filter. Present paper reviews the design of reconstruction filter considering the problems such as the effects of sampling rate, aliasing, and noise.

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Study of 『DongYangEuiYak』 (『동양의약(東洋醫藥)』 연구)

  • Jung, Ji Hun
    • The Journal of Korean Medical History
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    • v.15 no.2
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    • pp.101-108
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    • 2002
  • "DongYangEuiYak" is a magazine that was published three times to reconstruct Korean medicine. Publishing the magazine was leaded by excutives of the East and West Medicine Research Society, especially Kim younghun and Cho hunyoung. The magazine contains reconstruction of Korean medicine, medical history, pulse, herb, Sasang medicine and etc, in depth. Editorial department of "DongYangEuiYak" tried to boom Korean medicine and reeducate the people working in Korean medicine field by answering reader's questions and medical counselling articles and articles in correspondence course form. Studing courses and founding herb town after the publishment of "DongYangEuiYak", reflects well the culminated atmosphere of Korean medicine.

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Alveolar Ridge Preservation & Augmentation (치조제의 유지와 수복)

  • Chung, Sung-Min
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.7 no.1
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    • pp.32-40
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    • 1998
  • Alveolar ridge augmentation and preservation techniques designed to reconstruct deformed alveolar ridge now occupy a major role in esthetic dentistry. Previously, deformed alveolar ridges were filled with plastic materials(porcelain or resin) of prosthesis to restore ridge contours, which resulted in larger teeth and food impaction under the pontic base. So, prostheses of this type were unacceptable and really detectable when patients smiled. But nowadays, alveolar ridge augmentation procedures enable the dentists to provide patients with fixed prostheses that are esthetic. The development of guided tissue regeneration technique and materials also have made a major impact on extending the scope of therapeutic horizons in dentistry.

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Image restoration based on wavelet filter bank (웨이블렛 필터 뱅크를 이용한 영상복원)

  • 김주헌;이종수
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1387-1390
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    • 1997
  • In this paper we propose a novel way to restore degraded image using wavelet transform & filterbank. First, we devide a degraded image into 4-suband images using UDWT(Undecimated Wavelet Transform), and then use a proper CLS (Constrained Least Square) filter in each subband. Using a proper CLS filter ineach subband, we can save high grequency components of original image. We reconstruct a restored image from the downsampled subband images using wavelet tansform. Even though there is a trade-off between ISNR and calculation loads, we reduce the calculation loads by using wavelet transform in reconstruction with a negligible degradatiion in ISNR.

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High Quality Image Interpolation for Color Filter Arrays (Color Filter Array에 대한 고품질 영상보간기법)

  • 이봉준;이철희
    • Proceedings of the IEEK Conference
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    • 2000.06d
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    • pp.171-173
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    • 2000
  • In this paper, we present a new interpolation method for the color filter away(CFA). In order to capture color images. typical input devices use a single chip CCD imaging sensor with color filter array. As a result, the single chip CCD does not provide sufficient color resolutions since it arranges different color filters sequentially on a single CCD, resulting in aliasing noise and loss of resolution. In order to reconstruct high quality color images, we propose to use the interpolation algorithm using high order B-splines. Experiments show promising results.

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Digital Holographic Display Technology Trends (디지털 홀로그래픽 디스플레이 기술 동향)

  • Lim, Y.;Hong, K.;Park, M.;Kim, J.
    • Electronics and Telecommunications Trends
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    • v.32 no.5
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    • pp.30-38
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    • 2017
  • Digital holography is generally regarded as one of the most possible candidates for achieving a real 3D display system in that it can fully record and reconstruct the wave characteristics of light. In addition, 3D display systems based on digital holographic technology do not cause a vergence-accommodation mismatch problem. In this report, the recent trends in digital holographic display technology are described, and recent research results related to the fields of augmented reality and virtual reality are also briefly reported.