• Title/Summary/Keyword: pattern transformation

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Malignant Transformation of Craniopharyngioma without Radiation Therapy: Case Report and Review of the Literature

  • Jeong, Tae Seok;Yee, Gi Taek;Kim, Na Rae
    • Journal of Korean Neurosurgical Society
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    • v.60 no.1
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    • pp.108-113
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    • 2017
  • Craniopharyngiomas exhibiting histologic malignancy are extremely rare. Herein, we report the case of a 26-year-old male patient who underwent suprasellar mass excision via an interhemispheric transcallosal approach. Histopathological examination indicated that the craniopharyngioma was of the adamantinomatous subtype. The patient received postoperative medical treatment for endocrine dysfunction and diabetes mellitus without radiation treatment. Two years after the operation, he presented with progressive visual disturbance and altered mentality. Magnetic resonance imaging revealed a huge mass in the suprasellar cistern and third ventricle. He underwent a second operation via the same approach. The histopathological examination showed an adamantinomatous craniopharyngioma with sheets of solid proliferation in a spindled pattern, indicating malignant transformation. Malignant transformation of craniopharyngioma in the absence of radiation therapy has been reported in only five cases, including this one. We present a case of malignant transformation of craniopharyngioma with a brief review of relevant literature.

The Morphological Transformation Characteristics of Yanji in China through Space Syntax (공간구문론을 통한 중국 연길시 도시형태 변화과정 연구)

  • Kang, Wen-zhe;Yang, Seung-Woo
    • Journal of the Korean Institute of Rural Architecture
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    • v.13 no.4
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    • pp.115-124
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    • 2011
  • This study examines the process of urban formation in the city of Yanji. The analysis is done by the change of street pattern and major facility location in a timely manner by appling space syntax method. This research categorizes the pattern of the urban growth focused on two urban forms, street and major buildings, in the city and is offered of the meaning of the first value on interpretation of the urban growth in the city of Yanji. The result of the research are as follows. First, the period of the city transformation is divided into four stage; intuitive period, grid-iron formative period, consolidation period, and urban expansion period. Second, characteristics of each stage have been analyzed. At the first stage, the city started to frame along both buildings and streets which were placed without a plan. At the second stage, the city was planned and constructed into new grid-iron pattern ignoring existing context by Jananese colony. At the consolidation period, the road system expands from the city center toward suburban. At the last expansion period, the shape of the city has complicated its shape with complex road system. This study contributes to provide a basic analysis and data to investigate how the Yanji city has evolved over period of time. But further continuous research should be done for future urban development of the Yanji city.

Development of Mandibular Movements Measuring System Using Double Stereo-Cameras

  • Park, Soon-Yong;Park, Sung-Kee;Cho, Chang-Hyun;Kim, Mun-Sang;Park, Mi-Gnon
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1183-1188
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    • 2005
  • In this paper, we propose a 3D automated measuring system which measures the mandibular movements and the reference plane of the jaw movements. In diagnosis and treatment of the malocclusions, it is necessary to estimate the mandibular movements and the reference plane of the jaw movements. The proposed system is configured with double stereo-cameras, PC, two moving pattern plates(MPPs), two fixed pattern plates(FPPs) and one orbital marker. The virtual pattern plate is applied to calculate the homogeneous transformation matrices which describe the coordinates systems of the FPP and MPP with respect to the world coordinates system. To estimate the parameters of the hinge axis, the Euler's theorem is applied. The hinge axis points are intersections between the FPPs and the hinge axis. The coordinates of a hinge axis point with respect to the MPP coordinates system are set up to fixed value. And then, the paths of the jaw movement can be calculated by applying the homogeneous transformation matrix to fixed hinge axis point. To examine the accuracy of the measurements, experiments of measuring the hinge axis points and floating paths of them are performed using the jaw motion simulator. As results, the measurement errors of the hinge axis points are within reasonable boundary, and the floating paths are very similar to the simulator's moving path.

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Geometrical Reorientation of Distorted Road Sign using Projection Transformation for Road Sign Recognition (도로표지판 인식을 위한 사영 변환을 이용한 왜곡된 표지판의 기하교정)

  • Lim, Hee-Chul;Deb, Kaushik;Jo, Kang-Hyun
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.11
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    • pp.1088-1095
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    • 2009
  • In this paper, we describe the reorientation method of distorted road sign by using projection transformation for improving recognition rate of road sign. RSR (Road Sign Recognition) is one of the most important topics for implementing driver assistance in intelligent transportation systems using pattern recognition and vision technology. The RS (Road Sign) includes direction of road or place name, and intersection for obtaining the road information. We acquire input images from mounted camera on vehicle. However, the road signs are often appeared with rotation, skew, and distortion by perspective camera. In order to obtain the correct road sign overcoming these problems, projection transformation is used to transform from 4 points of image coordinate to 4 points of world coordinate. The 4 vertices points are obtained using the trajectory as the distance from the mass center to the boundary of the object. Then, the candidate areas of road sign are transformed from distorted image by using homography transformation matrix. Internal information of reoriented road signs is segmented with arrow and the corresponding indicated place name. Arrow area is the largest labeled one. Also, the number of group of place names equals to that of arrow heads. Characters of the road sign are segmented by using vertical and horizontal histograms, and each character is recognized by using SAD (Sum of Absolute Difference). From the experiments, the proposed method has shown the higher recognition results than the image without reorientation.

An Analytical Study on the Transformation Process of the Design Language of Frank O. Gehry (프랭크 게리의 조형 언어의 변천과정에 대한 분석 연구)

  • 이영화
    • Archives of design research
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    • v.16 no.2
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    • pp.219-232
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    • 2003
  • Frank O. Gehry is hewn to be an architect whose design 1anguage is so arbitrary and so unexpectedly changing that it seems to be almost impossible to trace any common language or my coherence over his entire career and works. To provide a counter-argument to this conception, this study explores the transformation pattern of the design language commanded by Gehry through his works. To pursue this study, Gehry's career was divided into four periods according to the design characteristics, and thorough analysis was conducted on the transformation pattern of the language both synchronically and diachronically. Based on the analysis, it was found that Gehry had been always trying to metaphorically embody the synchronic context of any given Period into his works, and the vehicles of this embodiment were materiality and morphology. Finally the argument of this study is that the changing process of Gehry's design language is not any "revolutionary change," as it was known to be, but 〃evolutionary transformation. "on."

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Size Transformation of Character Pattern (문자 패턴의 크기변환)

  • 이수연
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.11 no.2
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    • pp.85-92
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    • 1986
  • Hangeul wordprocessor, workstation and I/O device for telematic service are requiring many kinds of characters with various attributes such as size and font. In this paper, we survey computer algorithm that have been studied to transform(reduction, enlargement) built-in character patterns into character patterns with different sizes. Also, evaluation cirteria for such algorithms are mentioned.

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Anisotropic Whispering Gallery Modes Formed in Various Transformation Cavities (다양한 변환 공진기에 형성되는 비등방성 속삭임의 회랑 모드)

  • Kim, Inbo;Choi, Muhan
    • Korean Journal of Optics and Photonics
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    • v.29 no.3
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    • pp.104-109
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    • 2018
  • We explain the basic principle of transformation optics, and introduce several design techniques for transformation cavities that can maintain the characteristics of whispering gallery modes (WGMs) even if the cavity is strongly deformed from a circular shape. As a method of obtaining various transformation cavities under a specific conformal mapping, we suggest a method of parallel movement of the initial cavity domain, and a method of rotating the ellipse as a cavity domain. The internal wave pattern and the far-field output characteristics of several designed resonant modes are numerically calculated. From these results, it is confirmed that a variety of GRIN resonators are possible for a given conformal coordinate transformation.

The effectiveness of learning cycle approach to the construction of the concept of density and development of transformation ability of INRC group related to the concept of density (밀도개념과 밀도개념에 관련된 INRC 군 변환 능력의 형성에 미치는 순환학습의 효과)

  • Choi, Byung-Soon;Kim, Chung-Ho
    • Journal of The Korean Association For Science Education
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    • v.12 no.2
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    • pp.31-42
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    • 1992
  • The purposes of this study were to find out the degree of formation of the concept of density for the junior high students. The changing pattern of concept in acquiring the concept of density and the degree of development of INRC transformation ability related to the concept of density were also analyzed according to cognitive level and teaching method. The results of this study were as follows. 1) The experimental group were more effective than control group in the formation of the concept of density. 2) Even though students had been taught the concept of density, the various types of preconception were remained and persisted. Especially, the students at concrete level had persisted misconceptions and these misconceptions had been changed to the other misconceptions. 3) In the degree of the formation of the transformation ability of INRC group related to the concept of density in solid phase, the experimental group developed much better on both the abilities of Reciprocal transformation, Correlative transformation and the abilities to manipulate two variables such as volume and mass than control group. 4) The correlation coefficient between GALT score and achivement of the concept of density was 0.67. The correlation coefficient between achivement of the concept of density and the formation the transformation of INRC group related to the concept of density was 0.78.

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Localization for Mobile Robot Using Vertical Line Features (수직선 특징을 이용한 이동 로봇의 자기 위치 추정)

  • 강창훈;안현식
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.11
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    • pp.937-942
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    • 2003
  • We present a self-localization method for mobile robots using vertical line features of indoor environment. When a 2D map including feature points and color information is given, a mobile robot moves to the destination, and acquires images from the surroundings having vertical line edges by one camera. From the image, vertical line edges are detected, and pattern vectors meaning averaged color values of the left and right regions of the each line are computed by using the properties of the line and a region growing method. The pattern vectors are matched with the feature points of the map by comparing the color information and the geometrical relationship. From the perspective transformation and rigid transformation of the corresponded points, nonlinear equations are derived. Localization is carried out from solving the equations by using Newton's method. Experimental results show that the proposed method using mono view is simple and applicable to indoor environment.

A Study on Size Transformation for Dot Pattern by the 4-Direction Line Segmentation Algorithm (4방향 선분 분리법에 의한 도트 패턴의 크기 변화에 관한 연구)

  • 정회경;이수연
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.6
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    • pp.1013-1019
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    • 1987
  • This paper proposes the four directional line segmentation method to transform the size of dot patterns such as character dot patterns, line drawings and so on, while maintaining the quality of original pattern. At the first, this method extracts three kinds of line segmentm, namely horizontal, vertical line and slant line, and then transforms dot patterns using the each rules which are appricable to each kind of extracted line segments. Our experimental results show that transformation of dot patterns can be succeed in good quality without implementing some kinds of smoothing processes, covering the continuous transforming ratio of 0.5 to N times.

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