• Title/Summary/Keyword: Outer Contour

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Bladder And Rectum Dose Define 3D Treatment Planning for Cervix Cancer Brachtherapy Comparison of Dose-Volume Histograms for Organ Contour and Organ Wall Contour (자궁경부암의 고선량률 근접치료시 장기묘사 방법에 따른 직장과 방광의 선량비교 분석)

  • Kim, Jong-Won;Kim, Dae-Hyun;Choi, Joon-Yong;Won, Yeong-Jin
    • Journal of radiological science and technology
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    • v.35 no.4
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    • pp.327-333
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    • 2012
  • Purpose: To analyze the correlation between dose volume histograms(DVH) based on organ outer wall contour and organ wall delineation for bladder and rectum, and to compare the doses to these organs with the absorbed doses at the bladder and rectum. Material and methods: Individual CT based brachytherapy treatment planning was performed in 13 patients with cervical cancer as part of a prospective comparative trial. The external contours and the organ walls were delineated for the bladder and rectum in order to compute the corresponding dose volume histograms. The minimum dose in 0.1 $cm^3$, 1 $cm^3$, 2 $cm^3$, 5 $cm^3$, 10 $cm^3$ volumes receiving the highest dose were compared with the absorbed dose at the rectum and bladder reference point. Results: The bladder and rectal doses derived from organ outer wall contour and computed for volumes of 2 $cm^3$, provided a good estimate for the doses computed for the organ wall contour only. This correspondence was no longer true when large volumes were considered. Conclusion: For clinical applications, when volumes smaller than 5 $cm^2$ are considered, the dose-volume histograms computed from external organ contours for the bladder and rectum can be used instead of dose -volume histograms computed for the organ walls only. External organ contours are indeed easier to obtain. The dose at the ICRU rectum reference point provides a good estimate of the rectal dose computed for volumes smaller than 2 $cm^2$ only for a midline position of the rectum. The ICRU bladder reference point provides a good estimate of the dose computed for the bladder wall only in cases of appropriate balloon position.

Forming Tool Design of Outer Shell Structure of Nozzle Extension for Thrust Chamber (연소기 노즐확장부 외피구조물 성형치구 설계)

  • Ryu, Chul-Sung;Lee, Keum-Oh;Choi, Hwan-Seok
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.11a
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    • pp.271-275
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    • 2010
  • Forming tool design is carried out for a manufacturing a outer shell structure of the nozzle extension of regenerative cooling thrust chamber. The method which manufactures outer shell structure of nozzle extension is a metal forming process using thin plate. Because the configuration of outer shell structure is changed after forming process by springback effect, the outer shell structure can't be exactly formed with the same forming tool as configuration of the nozzle extension. Therefore forming tool design considering springback effect is necessary for manufacturing the outer shell structure of the nozzle extension. In this study, new designed forming tool configuration was generated to decrease the errors between nozzle contour and formed structure. The analysis results show that the errors between nozzle contour and formed structure is significantly decreased using the new designed forming tool.

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Number Plate Detection Using Topology of Characters and Outer Contour (문자간 위상관계와 외각에지를 이용한 차량번호판 추출기법)

  • Kim, Jae-Do;Han, Young-Joon;Hahn, Hern-Soo
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.1037-1038
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    • 2008
  • Since the characters are not clear always due to lighting conditions, sometimes only a part of the characters are detected and the boundary of the number plate is not completely shown. To solve this problem, this paper presents a new efficient algorithm for segmenting the number plate using the topological relationship among the characters in the number plate and its outer contour. The boundary of the number plate is estimated using the detected characters and detected by testing the connectivity of the vertical and horizontal edges. The superior performance of the proposed algorithm has been proved by the experiments.

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A Study on the Resonant Mode Identification in the Dielectric-disc Loaded Cylindrical Cavity Resonatorsv (유전체 디스크가 삽입된 원통형 공동 공진기에서의 공진 모드 구분에 관한 연구)

  • 이원희;김태신
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.1
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    • pp.37-45
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    • 2002
  • We described a method of resonant mode identification in dielectric-disc loaded cylindrical cavity resonators. The characteristic equations are solved using the ContourPlot graph of Mathematica. Contour graph method uses graphical method. It is comparable with numerical method. The numerical method is very difficult mode identification. The analysis is based on the approximated electromagnetic representation which is only concentrated on the calculation of resonant frequencies, and a mode identification of resonant frequencies has not been covered. However, It is possible to calculate precise resonant frequencies and to identify the mode of resonant frequencies using the contour graph method. The contour graph method is not a method using approximated representation of electromagnetic field variation at the outer area of dielectric in the resonators. It is a method using enact representation.

A Resonant Mode Identification in Cylindrical Cavity Resonators with Concentric-rod using Non-decaying Mode Analysis (유전체 봉이 삽입된 원통형 공동 공진기에서의 non-decaying 모드 해석을 이용한 공진 모드 구분)

  • Lee, Won-Hui;Kim, Tai-Shin;Kang, Min-Woo;Koo, Kyung-Wan;Hur, Jung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.1069-1072
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    • 2001
  • We described a method resonant mode identification in dielectric-rod loaded cylindrical cavity resonators. Resonant frequency of dielectric loaded cavity is calculated by analyzing the characteristic equation. The characteristic equation is solved by using the ContourPlot graph of Mathematica. As the result of comparing calculation value and experimental value of resonant frequencies, we know that the field representation of non-decaying mode is exact. The contour graph method is not a method using approximated representation of electromagnetic field variation at the outer area of dielectric in the resonators but a method using exact representation.

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Active Contour Model for Boundary Detection of Multiple Objects (복수 객체의 윤곽 검출 방법에 대한 능동윤곽모델)

  • Jang, Jong-Whan
    • The KIPS Transactions:PartB
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    • v.17B no.5
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    • pp.375-380
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    • 2010
  • Most of previous algorithms of object boundary extraction have been studied for extracting the boundary of single object. However, multiple objects are much common in the real image. The proposed algorithm of extracting the boundary of each of multiple objects has two steps. In the first step, we propose the fast method using the outer and inner products; the initial contour including multiple objects is split and connected and each of new contours includes only one object. In the second step, an improved active contour model is studied to extract the boundary of each object included each of contours. Experimental results with various test images have shown that our algorithm produces much better results than the previous algorithms.

Radiograph-based Diagnostic Methods for Thoracic and Lumbar Spine Malposition in Chuna Manual Therapy Using Biomarkers (단순 방사선 영상기반 바이오마커를 활용한 흉·요추의 추나의학적 변위 진단 방법)

  • Jin-Hyun Lee;Minho Choi;Joong Il Kim;Jun-Su Jang;Tae-Yong Park
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.18 no.2
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    • pp.1-8
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    • 2023
  • Objectives This study aimed to propose biomarkers for diagnosing Chuna manual therapy (CMT) based on X-ray images in the thoracic and lumbar spines. Methods Through a literature review and expert consensus process, diagnostic biomarkers for CMT were selected based on the listing system in thoracic and lumbar radiograph anterior-posterior (AP) and lateral views. Results 1. Diagnostic biomarkers were derived from four points on the outer contour of the vertebral body in the thoracic and lumbar spine radiograph lateral view, enabling the diagnosis of flexion and extension malposition. 2. Additional diagnostic biomarkers were identified in the thoracic and lumbar radiographAP view, utilizing points on the outer contour of the vertebral body. These biomarkers facilitate the diagnosis of lateral bending. Moreover, biomarkers derived from the innermost point of the pedicle contour allow for the diagnosis of rotation malposition. 3. Furthermore, through the biomarkers proposed in this study, all malpositions of the thoracolumbar spines and complex Type I and II malpositions can be diagnosed in CMT. Conclusions The biomarkers reported in this study consist of minimal points to determine the position of the vertebral body, providing the advantage of simplicity while minimizing potential errors during the CMT diagnostic process. Further clinical research and the development of related programs should be pursued to expand the evidence for CMT.

Filling and Labelling Algorithm Using Directional Information of Chain-code (체인코드의 방향정보를 이용한 Filling과 Labelling)

  • 심재창;하금숙;현기호;하영호
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.9
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    • pp.50-58
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    • 1992
  • A new algorithm for filling the interior of contours and labelling each filled region concurrently is presented. Filling is simply accomplished by inversion method. The labelling information in every scan lines is extracted directly from current direction of chain code so that the proposed algorithm needs less comparision and is more efficient. The contours are followed by two different directions, clockwise for the outer contour and counterclockwise for the inner contour to get filling and labelling information. This algorithm can be applied in case that contours are nested or regions are continous. Simulataneously the proposed algorithm can find the structure tree of object without additional post processing.

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Numerical Study on Combined Heat Transfer in NIR Dryer for Agricultural and Marine Products (근적외선 농수산물 건조기의 복합열전달특성에 관한 수치적 연구)

  • Choi, H.K.
    • Journal of Biosystems Engineering
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    • v.31 no.5 s.118
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    • pp.395-402
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    • 2006
  • Mixed heat transfer in an indirected NIR (Near Infrared Ray) dry chamber was investigated numerical analysis. It is Important that the miked heat transfer effects on double parameters which the Reynolds number and the position of emit lamp. Reynolds number are based on the outer diameter of the cylinder range from 103 to $30{\times}105$. Four difference heat transfer regimes of behavior are apparent: forced convection and radiation on the outer surface of the cylinder, pure conduction, pure natural convection and radiation between lamp surface and inner surface of the cylinder. The temperature and flow patterns are illustrated by iso-contour lines for the double parameters. Also presented are results on the convective heat transfer flux and the radiative heat transfer flux as increased with Reynolds number.

Deformation Characteristics of an Automotive Outer Door Panel by Vacuum-assisted Incremental Sheet Forming using Multi-tool paths (진공점진성형에서 복합공구경로가 차량용 외판부 도어패널의 변형특성에 미치는 영향 분석)

  • H.W. Youn;N. Park
    • Transactions of Materials Processing
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    • v.32 no.4
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    • pp.208-214
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    • 2023
  • This paper discusses the deformation characteristics of a scaled-down automotive outer door panel with vacuum-assisted incremental sheet forming. The vacuum condition between the die and Al6052-H32 sheet with a thickness of 1.0 mm is reviewed with the goal of improving the geometrical accuracy of the target product. The material flow according to the forming tool path, including the multi-tool path and conventional contour tool path, is investigated considering the degradation of the pillow effect. To reduce friction between the tool and the sheet during incremental forming, automotive engine oil (5W-30) is used as a lubricant, and the strain field on the surface of the formed product is analyzed using ARGUS. By comparing the geometry and material flow characteristics of products under different test conditions, it is confirmed that the product surface quality can be significantly improved when the vacuum condition is employed in conjunction with a multi-tool path strategy.