• Title/Summary/Keyword: reconstructed

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Bayesian Image Reconstruction Using Edge Detecting Process for PET

  • Um, Jong-Seok
    • Journal of Korea Multimedia Society
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    • v.8 no.12
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    • pp.1565-1571
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    • 2005
  • Images reconstructed with Maximum-Likelihood Expectation-Maximization (MLEM) algorithm have been observed to have checkerboard effects and have noise artifacts near edges as iterations proceed. To compensate this ill-posed nature, numerous penalized maximum-likelihood methods have been proposed. We suggest a simple algorithm of applying edge detecting process to the MLEM and Bayesian Expectation-Maximization (BEM) to reduce the noise artifacts near edges and remove checkerboard effects. We have shown by simulation that this algorithm removes checkerboard effects and improves the clarity of the reconstructed image and has good properties based on root mean square error (RMS).

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Reconstruction Models of Cretaceous Dinosaurs from Korea (한국에서 발견된 공룡의 복원과 모형제작)

  • 김항묵
    • Journal of the Korean Professional Engineers Association
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    • v.22 no.2
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    • pp.61-67
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    • 1989
  • The writer, a member of the Society of Vertebrate Paleontology(SVP), succeeds in making the miniatured dinosaur mcdels from the Early Cretaceous dinosaur remains of Korea. The dinosaur species of reconstruction models this time are the Ultrasaurus tabriensis KIM, the Iguanodon kimi KIM, and the Deinonychus koreanesis KIM. Those are reconstructed for the first time in Korea since the first discovery of dinosaur skeletons in 1973 from the country. The miniature models of dinosaurs reconstructed are exhibited by the photographs from lateral, frontal, and dorsal views.

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A Study on the Patient Data Back-up System (환자 정보 back-up 시스템에 관한 연구)

  • 이윤선;윤형로
    • Journal of Biomedical Engineering Research
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    • v.5 no.2
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    • pp.155-160
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    • 1984
  • In this paper, the patient data back-up system for medical and engineering field was designed. The system consists of 8-bit microprocessor, cassette recorder and data acquisition & control logic. To Inake data reduction, a Marked CORTES Algorythm which can be easily reconstructed was also designed in real time mode. In results, a Marked CORTES Algorythm produced about 35% data reduction rate and reconstructed good original data that are suitable Medician's reading.

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An Edge-detecting Bayesian Image Reconstruction for Positron Emission Tomography

  • Um, Jong-Seok;Choi, Byong-Su
    • Communications for Statistical Applications and Methods
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    • v.4 no.3
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    • pp.817-825
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    • 1997
  • Images reconstructed with EM algorithm have been observed to have checkerboard effects and have large distortions near edges as iterations proceed. We suggest a aimple algorithm of applying line process to the EM and Bayesian EM to reduce the distortions near edges. We show by simulation that this algorithm improves the clarity of the reconstructed image and has good properties based on root mean square error.

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A Spectral Inverse Scattering Technique by Using Low Pass Filters (저대역 필터를 사용한 파수영역에서의 역산란 방법)

  • 이재민;김세윤;라정웅
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.28A no.9
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    • pp.708-714
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    • 1991
  • In this paper, the noise contribution to the permit tivity profile reconstructed by the spectral inverse scattering scheme is investigated and a low-pass filter is proposed to reduce such the noise effects. Numerical simulations showed that the reconstructed profiles are affected by extremely large error. The suggested low-pass filter made it possible to reconstruct the permittivity profile nearly similar to the original. Furthermore, the optimal condition to the low-pass filter agreed well with the physical meaning even if several variables involved in the inverse scattering scheme were changed.

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Approximate Interpolator for Direct Fourier Reconstruction in Diffraction Tomography (회절 단층법에서 직접 푸리에 재구성을 위한 근사적 보간 함수에 관한 연구)

  • Lee, Moon Ho;Lim, Young Seok
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.1
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    • pp.167-172
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    • 1987
  • In this paper, the interpolation schemes for Direct Fourier Reconstruction in Diffraction Tomography are discussed. The interpolator using circular sampling theorem is modified so that the reconstructed image may be closer to original object than those produced with other interpolators. Reconstructed images obtained by computer simulations with several interpolators including that derived in this paper are compared to original object: two concentric cylinders.

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In Vitro Development of Interspecies Nuclear Transfer Embryos using Porcine Oocytes with Goat and Rabbit Somatic Cells

  • Quan, Yan Shi;Naruse, Kenji;Choi, Su-Min;Kim, Myung-Youn;Han, Rong-Xun;Park, Chang-Sik;Jin, Dong-Il
    • Reproductive and Developmental Biology
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    • v.32 no.4
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    • pp.249-253
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    • 2008
  • Interspecies somatic cell nuclear transfer (iSCNT) is a valuable tool for studying the interactions between an oocyte and somatic nucleus. The object of this study was to investigate the developmental competence of in vitro-matured porcine oocytes after transfer of the somatic cell nuclei of 2 different species (goat and rabbit). Porcine cumulus oocytes were obtained from the follicles of ovaries and matured in TCM-199. The reconstructed embryos were electrically fused with 2 DC pulses of 1.1kV/cm for $30{\mu}s$ 0.3M mannitol medium. The activated cloned embryos were cultured in porcine zygote medium-3 (PZM-3), mSOF or RDH medium for 7 days. The blastocyst formation rate of the embryos reconstructed from goat or rabbit fetal fibroblasts was significantly lower than that of the embryos reconstructed from porcine fetal fibroblast cells. However, a significantly higher number of embryos reconstructed from goat or rabbit fetal fibroblasts cultured in mSOF or RDH, respectively, developed to the morular stage than those cultured in PZM-3. These results suggest that goat and bovine fetal fibroblasts were less efficacious than porcine-porcine cloned embryos and that culture condition could be an important factor in iSCNT. The lower developmental potential of goat-porcine and porcine-bovine cloned embryos may be due to incompatibility between the porcine oocyte cytoplasm and goat and bovine somatic nuclei.

Study on Continuity of Elementary Mathematics Curriculum and Nuri Curriculum (유치원 교육과정과 초등수학 교육과정의 내용 연계성 분석 -누리과정과 2009 개정 수학과 교육과정을 대상으로-)

  • Chang, Hyewon;Lee, Hwayoung;Lim, Miin
    • Journal of Educational Research in Mathematics
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    • v.25 no.2
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    • pp.207-223
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    • 2015
  • This study aims to find ways for securing continuity of elementary mathematics curriculum and kindergarten curriculum. To do this, we considered the status of 'mathematical exploration' in Nuri curriculum and analysed the correspondence of content-domains and the continuity between Nuri curriculum for ages three to five and 2009 revised national elementary mathematics curriculum, based on the reconstructed achievement criteria. The result of these analyses reveals that the classification of five content-domains both for 'mathematical exploration' of Nuri curriculum and for 2009 revised national elementary mathematics curriculum coincides. We also recognized the reconstructed achievement criteria which are considered as reverse continuity or as discontinuity of Nuri curriculum and 2009 revised national elementary mathematics curriculum in all the five content domains. The former means being lower in levels or reduction in ranges from Nuri curriculum to elementary one. The latter means that some reconstructed achievement criteria are included in only one of the two curriculum. Based on these results, we suggested several ways to secure the continuity between Nuri curriculum and 2009 revised national elementary mathematics curriculum in the perspective of mathematics education.

The elimination of the linear artifacts by the metal restorations in the three dimensional computed tomographic images using the personal computer and software (개인용 컴퓨터와 소프트웨어를 이용한 3차원 전산화단층영상에서의 금속 수복물에 의한 선상 오류의 제거)

  • Park Hyok;Lee Hee-Cheol;Kim Kee-Deog;Park Chang-Seo
    • Imaging Science in Dentistry
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    • v.33 no.3
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    • pp.151-159
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    • 2003
  • Purpose: The purpose of this study is to evaluate the effectiveness and usefulness of newly developed personal computer-based software to eliminate the linear artifacts by the metal restorations. Materials and Methods: A 3D CT image was conventionally reconstructed using ADVANTAGE WINDOWS 2.0 3D Analysis software (GE Medical System, Milwaukee, USA) and eliminated the linear artifacts manually. Next, a 3D CT image was reconstructed using V-works 4.0/sup TM/(Cybermed Inc., Seoul, Korea) and the linear artifacts eliminated manually in the axial images by a skillful operator using a personal computer. A 3D CT image was reconstructed using V-works 4.0/sup TM/(Cybermed Inc., Seoul, Korea) and the linear artifacts were removed using a simplified algorithm program to eliminate the linear artifacts automatically in the axial images using a personal computer, abbreviating the manual editing procedure. Finally, the automatically edited reconstructed 3D images were compared to the manually edited images. Results and Conclusion: We effectively eliminated the linear artifacts automatically by this algorithm, not by the manual editing procedures, in some degree. But programs based on more complicated and accurate algorithms may lead to a nearly flawless elimination of these linear artifacts automatically.

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Teleoperation Using Reconstructed Graphic Model (재구성된 그래픽 모델을 이용한 원격제어)

  • Chung, Seong-Youb;Yoon, Hyun-Joong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.9
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    • pp.3876-3881
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    • 2012
  • In typical master/slave teleoperation systems, a human operator generally manipulates the master to control the slave through the visual information like camera image. However, the operator may get into trouble due to the limited visual information depending on the camera positions and the delay on the visual information because of low communication bandwidth. To cope with this inherit problem in the camera-based teleoperation system, this paper presents a teleoperation system using a reconstructed graphic model instead of the camera image. The proposed teleoperation system consists of a robot control module, a master module using a force-reflective joystick, and a graphic user interface (GUI) module. The graphic user interface module provides the operator with a 3D model reconstructed using a small set of sensing data received from the remote site. The proposed teleoperation system is evaluated through a peg-in-hole assembly task.