• Title/Summary/Keyword: Complex Images

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Image-guided surgery and craniofacial applications: mastering the unseen

  • Wang, James C.;Nagy, Laszlo;Demke, Joshua C.
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.37
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    • pp.43.1-43.5
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    • 2015
  • Image-guided surgery potentially enhances intraoperative safety and outcomes in a variety of craniomaxillofacial procedures. We explore the efficiency of one intraoperative navigation system in a single complex craniofacial case, review the initial and recurring costs, and estimate the added cost (e.g., additional setup time, registration). We discuss the potential challenges and benefits of utilizing image-guided surgery in our specific case and its benefits in terms of educational and teaching purposes and compare this with traditional osteotomies that rely on a surgeon's thorough understanding of anatomy coupled with tactile feedback to blindly guide the osteotome during surgery. A 13-year-old presented with untreated syndromic multi-suture synostosis, brachycephaly, severe exorbitism, and midface hypoplasia. For now, initial costs are high, recurring costs are relatively low, and there are perceived benefits of imaged-guided surgery as an excellent teaching tool for visualizing difficult and often unseen anatomy through computerized software and multi-planar real-time images.

SPECTRA OF THE IMAGES UNDER THE FAITHFUL $^*$-REPRESENTATION OF L(H) ON K

  • Cha, Hyung-Koo
    • Bulletin of the Korean Mathematical Society
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    • v.22 no.1
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    • pp.23-29
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    • 1985
  • Let H be an arbitrary complex Hilbert space. We constructed an extension K of H by means of weakly convergent sequences in H and the Banach limit. Let .phi. be the faithful *-representation of L(H) on K. In this note, we investigated the relations between spectra of T in L(H) and .phi.(T) in L(K) and we obtained the following results: 1) If T is a compact operator on H, then .phi.(T) is also a compact operator on K (Proposition 6), 2) .sigma.$_{l}$ (.phi.(T)).contnd..sigma.$_{l}$ (T) for any operator T.mem.L(H) (Corollary 10), 3) For every operator T.mem.L(H), .sigma.$_{ap}$ (.phi.(T))=.sigma.$_{ap}$ (T))=.sigma.$_{ap}$ (T)=.sigma.$_{p}$(.phi.(T)) (Lemma 12, 13) and .sigma.$_{c}$(.phi.(T))=.sigma.(Theorem 15).15).

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An Algorithm for the Characterization of Surface Crack by Use of Dipole Model and Magneto-Optical Non-Destructive Inspection System

  • Lee, Jin-Yi;Lyu, Sung-Ki;Nam, Young-Hyun
    • Journal of Mechanical Science and Technology
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    • v.14 no.10
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    • pp.1072-1080
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    • 2000
  • Leakage magnetic flux (LMF) is widely used for non-contact detection of cracks. The combination of optics and LMF offers advantages such as real time inspection, elimination of electrical noise, high spatial resolution, etc. This paper describes a new nondestructive evaluation method based on an original magneto-optical inspection system, which uses a magneto-optical sensor, LMF, and an improved magnetization method. The improved magnetization method has the following characteristics: high observation sensitivity, independence of the crack orientation, and precise transcription of the geometry of a complex crack. The use of vertical magnetization enables the visualization of the length and width of a crack. The inspection system provides the images of the crack, and shows a possibility for the computation of its depth.

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Extraction of Geometric and Color Features in the Tobacco-leaf by Computer Vision (컴퓨터 시각에 의한 잎담배의 외형 및 색 특징 추출)

  • Cho, H.K.;Song, H.K.
    • Journal of Biosystems Engineering
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    • v.19 no.4
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    • pp.380-396
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    • 1994
  • A personal computer based color machine vision system with video camera and fluorescent lighting system was used to generate images of stationary tobacco leaves. Image processing algorithms were developed to extract both the geometric and the color features of tobacco leaves. Geometric features include area, perimeter, centroid, roundness and complex ratio. Color calibration scheme was developed to convert measured pixel values to the standard color unit using both statistics and artificial neural network algorithm. Improved back propagation algorithm showed less sum of square errors than multiple linear regression. Color features provide not only quality evaluation quantities but the accurate color measurement. Those quality features would be useful in grading tobacco automatically. This system would also be useful in measuring visual features of other agricultural products.

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An Experimental Study on Turbulent Counter Jet Flame near Stagnation Point (대향 제트 정체점 주변의 난류 화염에 관한 연구)

  • Ko, Il-Min;Seo, Jeong-Il;Hong, Jung-Goo;Shin, Hyun-Dong
    • 한국연소학회:학술대회논문집
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    • 2006.04a
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    • pp.128-134
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    • 2006
  • A characterization of turbulent reacting flows has proved difficult owing to the complex interaction between turbulence, mixing, and combustion chemistry. There are many types of time scales in turbulent flame which can determine flame structure. This counter jet type premixed burner produces high intensity turbulence. The goal is to gain better insights into the flame structures at high turbulence. 6 propane/air flames gave been studied with high velocity fluctuation in bundle type nozzle and in one hole type nozzle. By measuring velocity fluctuation, turbulent intensity and integral length scale are obtained. And sets of OH LIF images were processed to see flame structure of the mean flame curvatures and flame lengths for comparison with turbulence intensity and turbulent length scales. The results show that the decrease in nozzle size generates smaller flow eddy and mean curvatures of the flame fronts, and a decrease in Damkohler number estimated from flow time scale measurement.

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Speed Optimization Design of 3D Medical Image Reconstruction System Based on PC (PC 기반의 3차원 의료영상 재구성 시스템의 고속화 설계)

  • Bae, S.H.;Kim, S.H.;Yoo, S.K.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.546-549
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    • 1997
  • 3D medical image reconstruction techniques are useful to figure out complex 3D structure from the set of 2D sections but their implementations are difficult due to processor's limitation and their computational complexity. In this paper, we propose a new speed optimization technique or accelerating the volume rendering algorithm. In addition, the whole procedure or reconstructing the medical images are constructed by using Visual C++ 5.0 under PC environment. They include classification, shading and ray-casting.

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A study of three dimensional reconstruction of medical images based on the Delaunay triangulation (Delaunay triangulation을 이용한 3차원 의료영상 재구성에 관한 연구)

  • Kwon, E.C.; Kim, D.Y
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.273-274
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    • 1998
  • We construct a volume whose boundary is a tetrahedron with triangular faces intersecting the cutting planes along the given contours. This volume is obtained by calculating the Delaunay triangulation slice by slice, mapping 2D to 3D as tetrahedron. Also, eliminate extra-voronoi skeleton and non-solid tetrahedron. In this paper, we propose new method to eliminate non-solid tetrahedron based on the modified extra-voronoi skeleton path. This method enable us to do a compact tetrahedrisation and to reconstruct complex shapes.

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A Study on The Visual Inspection of Fabric Defects (시각 장치를 이용한 직물 결함 검사에 관한 연구)

  • Kyung, Kye-Hyun;Ko, Myoung-Sam;Lee, Sang-Uk;Lee, Bum-Hee
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.959-962
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    • 1988
  • This paper describes an automatic visual inspection system for fabric defects based on pattern recognition techniques. The inspection for fabric defects can be separated into three sequences of operations which are the detection of fabric defects[1], the classification of figures of fabric defects, and the classification of fabric defects. Comparing projections of defect-detected images with the predefined complex, the classification accuracy of figures of fabric defects was found to be 95.3 percent. Employing the Bayes classifier using cluster shade in SGLDM and variance in decorrelation method as features, the classification accuracy of regional figure defects was found to be 82.4 percent. Finally, some experimental results for line and dispersed figures of fabric defects are included.

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A Study on the Theory and Application for the Morphological Aspects of Hybrid Spatial Structures (대공간구조물의 형태결정에 관한 이론 및 응용에 관한 연구)

  • 이경수;이상주;유용주;한상을
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.04a
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    • pp.272-279
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    • 1998
  • The purpose of this study is to show how to gain the morphology of the Hybrid Spatial Structures and to get the geometrical data such as node coordinates, member relationships and graphic images. To form spatial structures, we have developed morphological aspects of general spatial structures, programming process and techniques. Structural design has many processes. Especially, it is very important to consider the determination of structural configuration. Regular Hybrid Spatial Structures have complex configuration, so we need to make use of automated computer process to determine structural shape in Hybrid Spatial Structures. We have applied morphological aspects to double layer plate, single layer dome, double layer dome and tensegrity structure.

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A Study on Three-Dimensional Computer Generated Holograms by 3-D Coordinates Transformation (3차원 좌표변환에 의한 입체 컴퓨터 형성 홀로그램에 관한 연구)

  • Ryu, Won-Hyeon;Jeong, Man-Ho
    • Korean Journal of Optics and Photonics
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    • v.17 no.6
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    • pp.525-531
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    • 2006
  • Synthesized 3-D CGH of a general three dimensional object is obtained by using a new 3-D coordinates transformation technique. A CCD camera is used to record several projected images of the 3-D object from different viewing angles. The recorded data are numerically calculated and processed to yield two-dimensional complex functions, which are then encoded fer the final synthesized 3-D CGH.