• Title/Summary/Keyword: 3D experiments

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A Study on the Experiments and Prediction of Desulfurization Efficiency in Fluidized Bed Combustor (유동층연소로에서 탈황효율 실험 및 예측에 관한 연구)

  • 조상원;김영식
    • Journal of Environmental Health Sciences
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    • v.28 no.5
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    • pp.93-101
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    • 2002
  • We have studied that the prediction of desulfurization efficiency by limestone in fluidized-bed coal combustor. The results were presented as follows : Firstly, the bed temperature had a great deal of effect on the desulfurization and the optimum temperature of limestone was 85$0^{\circ}C$~90$0^{\circ}C$. Secondly, as the velocity and temperature increased, $K_{s}$, K and the desulfurization efficiency increased. So, $k_{s}$, $k_{d}$ highly depended on the air velocity and bed temperature, and $k_{s}$, $k_{d}$ were 82.53 mm/sec, 0.0041/sec at 0.2 m/sec, 85$0^{\circ}C$, $k_{s}$, $k_{d}$ were 125.62 mm/sec. 0.00532/sec at 0.3 m/sec, 80$0^{\circ}C$ respectively. And $k_{s}$, $k_{d}$ were 143.78 mm/sec, 0.00568/sec at 0.3 m/sec, 85$0^{\circ}C$. Thirdly, as a result of desulfurization modeling, there was good agreement between theory and experiments as anthracite fraction increased. At 3.0 of optimum Ca/S molar ratio, there was very good agreement between theory and experiments.riments.riments.s.

Hydraulic experiments on change of intervals between submerged structure and breakwater (수중구조물과 방파제 간의 거리변화에 따른 수리 특성 실험)

  • Park, Seung-Hyun;Park, Jin-Ho;Cho, Yong-Sik
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.168-171
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    • 2007
  • The stability of a typical rubble mound breakwater defenced by a submerged structure is investigated using hydraulic experiments. Incident irregular waves are obtained from the Bretschneider-Mistuyasu spectrum. Experiments are carried out for different spacings between two breakwaters (X/d=2-3) and for different relative widths (B/h=0.7-3.0) of the submerged structure. It is observed that a submerged structure of (B/h) of 0.7-3.0 constructed at a seaward distance (X/d) of 2-3 breaks all the incident waves and dissipates energy and breakwater.

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3D Line Segment Detection using a New Hybrid Stereo Matching Technique (새로운 하이브리드 스테레오 정합기법에 의한 3차원 선소추출)

  • 이동훈;우동민;정영기
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.4
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    • pp.277-285
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    • 2004
  • We present a new hybrid stereo matching technique in terms of the co-operation of area-based stereo and feature-based stereo. The core of our technique is that feature matching is carried out by the reference of the disparity evaluated by area-based stereo. Since the reference of the disparity can significantly reduce the number of feature matching combinations, feature matching error can be drastically minimized. One requirement of the disparity to be referenced is that it should be reliable to be used in feature matching. To measure the reliability of the disparity, in this paper, we employ the self-consistency of the disunity Our suggested technique is applied to the detection of 3D line segments by 2D line matching using our hybrid stereo matching, which can be efficiently utilized in the generation of the rooftop model from urban imagery. We carry out the experiments on our hybrid stereo matching scheme. We generate synthetic images by photo-realistic simulation on Avenches data set of Ascona aerial images. Experimental results indicate that the extracted 3D line segments have an average error of 0.5m and verify our proposed scheme. In order to apply our method to the generation of 3D model in urban imagery, we carry out Preliminary experiments for rooftop generation. Since occlusions are occurred around the outlines of buildings, we experimentally suggested multi-image hybrid stereo system, based on the fusion of 3D line segments. In terms of the simple domain-specific 3D grouping scheme, we notice that an accurate 3D rooftop model can be generated. In this context, we expect that an extended 3D grouping scheme using our hybrid technique can be efficiently applied to the construction of 3D models with more general types of building rooftops.

Image Processing for 3-D Shape Estimation of Specular Reflection (경면반사체의 3차원 형상 추정을 위한 영상처리)

  • Kim, Jee-Hong;Cho, Byung-Gwon
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.4
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    • pp.1-9
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    • 2012
  • A method to estimate the 3-D shape of surface with specular reflection is proposed, where the difference between the images reflected from a flat surface and a curved surface is used. First, we analyzed the geometry of the spatial reflection at specular surface and the variation of reflected light due to curved surface, whose results are used to estimate 3-D shape. The proposed method is shown to be effective via experiments using the illumination with spatially distributed light source and the CCD camera to capture the light reflected from a surface. In experiments, the captured images from curved surface with specular reflection are processed to approximately estimate 3-D shape.

Virtual Experimental Characterization of 3D Orthogonal Woven Composite Materials (직교 직물 복합재료 물성치 예측을 위한 가상 수치 실험)

  • Lee, Chang-Sung;Shin, Hun;Kim, Seung-Jo
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2001.05a
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    • pp.205-210
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    • 2001
  • In this work, virtual material characterization of 3D orthogonal woven composites is performed to predict the elastic properties by a full scale FEA. To model the complex geometry of 3D orthogonal woven composites, an accurate unit structure is first prepared. The unit structure includes warp yarns, filler yarns, stuffer yams and resin regions and reveals the geometrical characteristics. For this virtual experiments by using finite element analysis, parallel multifrontal solver is utilized and the computed elastic properties are compared to available experimental results and the other analytical results. It is founded that a good agreement between material properties obtained from virtual characterization and experimental results. Using the method of this virtual material characterization, the effects of inconsistent filler yarn distribution on the in-plane shear modulus and filler yarn waviness on the transverse Young's modulus are investigated. Especially, the stiffness knockdown of 3D woven composite structures is simulated by virtual characterization. Considering these results, the virtual material characterization of composite materials can be used for designing the 3D complex composite structures and may supplement the actual experiments.

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Segmentation of 3D Visible Human Color Images by Balloon (Balloon을 이용한 3차원 Visible human 컬러 영상의 분할 방법)

  • 김한영;김동성;강흥식
    • Proceedings of the IEEK Conference
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    • 2001.06e
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    • pp.73-76
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    • 2001
  • A segmentation is a prior processing for medical image analysis and 3D reconstruction. This Paper provides the method to segment 3D Visible Human color images. Firstly, the reference images that have a initial curve are segmented using Balloon and the results are propagated to the adjacent images. In the propagation processing, the result of the adjacent slice is modified by Edge-limited SRG Finally, the 3D Balloon improves the segmentation results of each 2D slice. the proposed method's performance was verified through the experiments to segment thigh muscles of Visible Human color images.

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EVALUATION OF TECHNIQUES FOR ESTIMATING MILK PRODUCTION BY SOWS 1. DEUTERIUM OXIDE DILUTION METHOD FOR ESTIMATING MILK INTAKE BY PIGLETS

  • Prawirodigdo, S.;King, R.H.;Dunkin, A.C.;Dove, H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.3 no.2
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    • pp.135-141
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    • 1990
  • Two experiments were conducted to determine the validity of the deuterium oxide ($D_2O$) dilution method to estimate milk intake by pigs. A total of 39 piglets weaned from their dams 24 - 36 hours after birth and trained to drink from artificial nipples, were used for two experiments. Estimates of milk replacer consumption of individual piglets over 1, 3, 5 and 7 days were made by the $D_2O$ dilution method and by dissappearance. Milk intakes estimated by this $D_2O$ dilution method were significantly correlated ($R^2$ = 0.98-0.99) with milk intake measured by disappearance. The average difference between estimates by disappearance and estimates by the $D_2O$ dilution method were -1%, +0.5%, +0.5% and -2.1% for measurement period of 1, 3, 5 and 7 days respectively.

Accuracy Improvement of Analysis Results Obtained from Numerical Analysis Model of Continuously Reinforced Concrete Pavement (연속철근 콘크리트 포장 수치해석 모델의 해석결과 정확도 개선 방법)

  • Cho, Young Kyo;Seok, Jong Hwan;Choi, Lyn;Kim, Seong-Min
    • International Journal of Highway Engineering
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    • v.18 no.1
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    • pp.73-83
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    • 2016
  • PURPOSES : The purpose of this study is to develop a method for improving the accuracy of analysis results obtained from a two-dimensional (2-D) numerical analysis model of continuously reinforced concrete pavement (CRCP). METHODS : The analysis results from the 2-D numerical model of CRCP are compared with those from more rigorous three-dimensional (3-D) models of CRCP, and the relationships between the results are recognized. In addition, the numerical analysis results are compared with the results obtained from field experiments. By performing these comparisons, the calibration factors used for the 2-D CRCP model are determined. RESULTS : The results from the comparisons between 2-D and 3-D CRCP analyses show that with the 2-D CRCP model, concrete stresses can be overestimated significantly, and crack widths can either be underestimated or overestimated by a slight margin depending on the assumption of plane stress or plane strain. The behaviors of crack width in field measurements are comparable to those obtained from the numerical model of CRCP. CONCLUSIONS : The accuracy of analysis results from the 2-D CRCP model can be improved significantly by applying calibration factors obtained from comparisons with 3-D analyses and field experiments.

Effect of Dissolved Oxygen on the Growth of Azotobacter vinelandii UWD and Production of PHBV in the Mixture of Organic Acids and Glucose (유기산 및 포도당 혼합배지에서 Azotobacter vinelandii UWD의 생장 및 PHBV 생산에 대한 용존산소의 영향)

  • 박창호
    • KSBB Journal
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    • v.13 no.6
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    • pp.675-680
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    • 1998
  • In both 7L and 20L fermentor experiments the level of dissolved oxygen (D.O) strongly affected growth and PHBV production of Azotobacter vinelandii UWD. A higher D.O. increased carbon substrate consumption rate and cell growth rate with a similar residual biomass production. However, a lower D.O. was a much better condition for PHBV production. In a 20L fermentor experiments controlled at 5% D.O. cell growth rate was about twice faster(0.555 hr-1 and 0.260 hr-1 at the acid and the glucose phase, respectively) with an equal amount(4.5 g/L) of residual biomass production. However, PHBV content in the cell(62.3 wt%) increased 17.3 times at 1% D.O.

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Pose-normalized 3D Face Modeling for Face Recognition

  • Yu, Sun-Jin;Lee, Sang-Youn
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.12C
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    • pp.984-994
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    • 2010
  • Pose variation is a critical problem in face recognition. Three-dimensional(3D) face recognition techniques have been proposed, as 3D data contains depth information that may allow problems of pose variation to be handled more effectively than with 2D face recognition methods. This paper proposes a pose-normalized 3D face modeling method that translates and rotates any pose angle to a frontal pose using a plane fitting method by Singular Value Decomposition(SVD). First, we reconstruct 3D face data with stereo vision method. Second, nose peak point is estimated by depth information and then the angle of pose is estimated by a facial plane fitting algorithm using four facial features. Next, using the estimated pose angle, the 3D face is translated and rotated to a frontal pose. To demonstrate the effectiveness of the proposed method, we designed 2D and 3D face recognition experiments. The experimental results show that the performance of the normalized 3D face recognition method is superior to that of an un-normalized 3D face recognition method for overcoming the problems of pose variation.