• 제목/요약/키워드: Radiatin

검색결과 6건 처리시간 0.027초

유전체로 채워진 유한한 슬롯을 가지는 평행평판 도파관 누설파 안테나 구조에 대한 특성 모드 해석 (Characteristics mode analysis for the finite slotted parallel-plate waveguide as a leaky wave antenna structure)

  • 윤이호;조영기
    • 전자공학회논문지D
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    • 제34D권10호
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    • pp.32-38
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    • 1997
  • A characteristic mode analysis of parallel-plate waveguide with finite number of slot as a leaky wav eantenna structure is considered for calculating the characteristics currents, the characteristic patterns, radiatin patterns, and the complex propagation constants. For the cases of 1, 11 and 29 slots, numericl resutls for the equivalent magnetic currents, the radiatin patterns, and thecomplex propagation constants are computed and compared with those obtained by use of the conventional method of moments. Good correspondence between them is observed.

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초대형 부유식 해상공항의 시설계 (일반배치와 깊이 결정) (Trial Design of a Very Large Floating Airport (General Arrangement and Decision of Depth))

  • 신현경;임춘규;정재희
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2001년도 추계학술대회 논문집
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    • pp.45-49
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    • 2001
  • The length and the breadth or a very large floating airport are determined by airplane types and airport facilities. However, the depth affect not only the structural strength but also the functional requirement such as a possibility of taking off and landing. The optimization problem for determining the depth is to select a design so that the cost is minimized. In this paper, a general arrangement and a method to decide the depth are proposed. Strength, functional requirement, and possibility of occurrence of deck wetness and slamming are considered in order to determine the depth of structure. Hydrodynamic forces of the diffraction and radiatin problems are predicted by applying the source-dipole distribution method, and the structural responses are obtained by the finite element method.

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제트 확산화염의 연소특성과 매연생성에 관한 연구 (Combustion Characteristics and Soot Formation in a Jet Diffusion Flame)

  • 이교우;백승욱
    • 대한기계학회논문집
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    • 제18권10호
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    • pp.2712-2723
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    • 1994
  • Numerical simulation of an axisymmetric ethylene-air jet diffusion flame has been carried out in order to investigate flame dynamics and soot formation. The model solves the time-dependent Navier-Stokes equations and includes models for soot formation, chemical reaction, molecular diffusion, thermal conduction, and radiation. Numerically FCT(Flux Corrected Transport) and DOM(Discrete Ordinate Method) methos are used for convection and radiation trasport respectively. Simulation was conducted for a 5 cm/sec fuel jet flowing into a coflowing air stream. The maximum flame temperature was found to be approximately 2100 K, and was located at an axial position of approximately 5 cm from the base of the flame. The maximum soot volume fraction was about $7{\times}10^{-7}$, and was located within the high temperature region where the fuel mole fraction ranges from 0.01 to 0.1. The buoyancy-driven low-frequency(12~13 Hz) structures convected along the outer region of the flame were captured. In case without radiation trasport, the maximum temperature was higher by 150 K than in case with radiation. Also the maximum soot volume fraction reached about $8{\times}10^{-6}$. As the the hydrocarbon fuel forms many soot particles, the radiation transport becomes to play a more important role.

조사야 확인용 film을 이용한 자궁 경부암 환자의 조사야 정확성 연구 (The analysis of radiatin field accuracy in uterine cervical cancer patients using verification films.)

  • 정희영;권영호;정덕양;황웅구;김유현
    • 대한방사선치료학회지
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    • 제7권1호
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    • pp.133-145
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    • 1995
  • 1. Purpose : 30 patients with uterine cervical cancer who had been treated at Department of radiation Oncology of Korea university Hospital from June, 1, 1994. to December. 31, 1994. were analyzed to the radiation field accuracy using verification films. 2. Methods and Materials : 30 patients were divided by 6 groups, 5 patients respectively : Group (1) : Standard physique, supine not-fixed Group (2) : Standard physique, supine fixed Group (3) : Obesity physique, supine, not-fixed Group (4) : Obesity physique, supine, not-fixed Group (5) : Obesity physique, prone, not-fixed Group (6) : Obesity physique, prone, fixed All groups were taken verification fimls during the whole treatment period, and it compared with simulation films and portal fimls, 3. Results : This results suggest that all patients should be immovilized and especially obesity physique patients should be treated by prone position in order to reduce radiation field discrepancy. In addition, this results should help to prescribe appropriate safty margins for patients simulation.

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두개 내 다형성아교모세포종 환자의 방사선치료 결과 (The Outcome of Glioblastoma Patients Treated with Surgery and Radiation Therapy)

  • 남희림;임도훈;안용찬;이정일;남도현;김종현;홍승철;이정은;강민규;박영제;김경주;박원;허승재
    • Radiation Oncology Journal
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    • 제22권2호
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    • pp.91-97
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    • 2004
  • 목적 : 두개 내 다형성아교모세포종 환자의 방사선치료 후 생존율을 조사하고 그 예후 인자의 중요성을 알아보고자 하였다. 대상 및 방법: 1994년부터 2003년까지 삼성서울병원에서 병리학적으로 다형성아교모세포종으로 확진된 환자 중 근치적 목적으로 방사선치료를 시행한 120명을 대상으로 분석하였다. 남자는 64명(53$\%$), 여자는 56명(47$\%$)이었으며, 20례(17$\%$)의 종양은 다발성이었다. 수술은 육안적 완전 절제, 부분 절제 및 조직검사를 각각 22례(18$\%$), 59례(58$\%$), 29례(24$\%$)에서 시행하였고, 방사선치료는 4$\~$10 WV 선형가속기를 이용하여 54$\~$72Gy (중앙값 60 Gy)를 조사하였다. 대상 환자의 추적관찰기간은 2개월에서 62개월(중앙값 12개월)이었다. 결과 : 전체 환자군의 1년 및 2년 생존율은 52$\%$와 14$\%$이었으며, 중앙생존기간은 13개월이었다. 예후 인자에 따른 1년 생존율은 50세 미만은 64$\%$, 50세 이상은 41$\%$ (p<0.01), 수술 전 활동도가 ECOG 0 혹은 1인 경우 는 57$\%$, 2 이상은 44$\%$ (p=0.03)였다. 두개 내 병변 수에 따른 1년 생존율은 단일병변은 57$\%$, 다발성 병변은 23$\%$ (p=0.02)이었으며, 절제정도에 따른 생존율은 육안적 완전 절제, 부분 절제, 조직검사만 시행한 경우에 각각 67$\%$, 48$\%$, 47$\%$ (p=0.04)였다. 다변량 분석에 따른 예후인자로는 여자(p<0.01), 50세 미만(p<0.01), 활동도가 ECOG 0 혹은 1 (p=0.05), 육안적 완전절제(p=0.05)가 좋은 예후 인자이었다 결론 : 근치적 목적으로 방사선치료를 시행한 두개 내 다형성아교모세포종 환자의 중앙생존기간은 13개월로 기존의 문헌보고와 비슷한 수준이었다. 치료성적의 향상을 위하여 다양한 방사선치료 기술의 적용을 통한 방사선량의 증가와 효과적인 항암화학요법 약제의 개발 및 사용 등의 연구가 필요하고, 환자의 예후인자에 따라 개별화된 치료방법이 적용되어야 할 것으로 판단된다