• 제목/요약/키워드: Radiation Pattern

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방사선폐렴 변증(辨證)도구 개발을 위한 기초연구 (Preliminary Study for Development of Pattern Identification Tool for Radiation Pneumonitis)

  • 김재효;방연희;도하윤;안준모;김관일;이범준;정승기;정희재
    • 대한한방내과학회지
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    • 제38권1호
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    • pp.32-47
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    • 2017
  • Objective: The purpose of this study was to develop a standard tool for pattern identification of radiation pneumonitis. Methods: Textbooks, published studies, and references with comments about patterns were reviewed. Through the Delphi method, we determined pattern identifications based on advice from a committee of experts composed of 13 Korean respiratory internal medicine professors. Results: Using the Delphi method, four pattern identifications were chosen: Qi Deficiency (氣虛), Yin Deficiency (陰虛), Heat Toxin (熱毒), and Phlegm Dampness (痰濕). The tool was developed in a question-and-answer format with 35 questions. Conclusions: A pattern identification tool that can discriminate the patterns of radiation pneumonitis for standardized diagnosis was developed through expert consultation. Further study of its validity and reliability is necessary.

ENG 영차 공진을 이용하여 대역폭이 개선되고 지향성 방사 패턴을 갖는 하이브리드 안테나 (Broadband Hybrid Antenna with Directional Radiation Pattern Utilizing Epsilon Negative Zeroth-Order Resonance)

  • 김인호;이정혜
    • 한국전자파학회논문지
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    • 제21권8호
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    • pp.886-892
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    • 2010
  • 본 논문에서는 epsilon negative(ENG) 영차 공진과 $TM_{010}$-모드를 결합하여 넓은 대역폭을 갖고, 지향성 방사 패턴을 갖는 하이브리드 안테나를 제안한다. ENG 영차 공진을 얻기 위해 버섯 구조를 이용하였고, $TM_{010}$ 모드를 얻기 위해 패치 안테나를 이용하였다. 이 두 개의 안테나 사이에 갭을 주어 하나의 동축 선로 급전 구조로 두 개의 안테나를 결합하였다. ENG ZOR 주파수는 4 GHz, $TM_{010}$의 주파수는 3.9 GHz로 설계하였다. 두 주파수가 근접해 있기 때문에 이중 공진을 형성할 수 있고, 따라서 대역폭을 확장시킬 수가 있다. ENG ZOR 안테나는 전방향성의 방사 패턴을 갖지만, ENG ZOR 주파수와 $TM_{010}$의 주파수가 매우 근접해 있기 때문에 전방향성의 방사 패턴의 널 부분을 $TM_{010}$ 모드 방사가 보상해줄 수 있어 제안된 안테나는 지향성 방사 패턴을 갖는다. 제안된 안테나는 버섯 구조의 단위 셀을 각각 4개, 3개, 2개로 줄여나가면서 3가지 종류로 설계하여 특성을 분석하였다. 각각의 제안된 안테나는 비대역폭 $4.29{\sim}4.95 %$, 이득 3.16~5.57 dBi, 효율 62.4~94.2 %의 특성을 가지고 있다.

LCD Back-Light Unit 설계를 위한 최적화 기법 (Optimization Method for the Design of LCD Back-Light Unit)

  • 서희경;류양선;최준수;한광수;김성철
    • 한국정보과학회논문지:시스템및이론
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    • 제32권3호
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    • pp.133-147
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    • 2005
  • LCD BLU(Back-Light Unit)의 설계에는 광선추적 기법이 많이 사용되고 있으며, 이러한 기법을 통하여 도광판 전면으로 출사되는 빛의 휘도, 휘도의 균일도, 광효율 등을 수치적으로 예측할 수 있다. 휘도와 휘도의 균일도 등과 같은 항목은 BLU 설계에 있어서 매우 중요한 요소 중의 하나이며, 이러한 BLU의 광학적 특성은 도광판의 후면에 인쇄된 잉크패턴에 가장 많을 영향을 받고 있다 따라서 높은 휘도와 균일도를 발생시킬 수 있는 최적화된 잉크패턴을 설계하는 것은 BLU의 설계에 있어서 가장 중요한 부분 중의 하나이다. 본 논문에서는 최적의 잉크패턴을 설계하기 위하여 직접탐색(Direct Search) 기법 중에서 Holder Mead의 심플렉스탐색(Simplex Search) 알고리즘을 적용하였다. 직접탐색 기법은 최적의 잉크패턴을 계산하는 것과 같은 비선형적이고, 비연속적이며, 미분불가능한 함수의 최적점을 계산하는 분야에 많이 적용되고 있다. 본 논문에서는 여러 가지 실험을 통하여 심플렉스탐색 기법이 최적의 잉크패턴을 설계하는데 있어서 매우 효율적이며 안정적으로 사용될 수 있음을 보여주며, 이러한 최적화 기법으로 인하여 BLU 설계기능을 개선할 수 있음을 보여준다

초음파진동자의 복수배열에 의한 지향성가변에 관한 연구 (A Study on the Control of the Radiation Pattern of an Ultra-Sonic Beam by the Plural Arrangement of the Transducers)

  • 신형일
    • 한국항해학회지
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    • 제3권2호
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    • pp.21-30
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    • 1979
  • Echo sounder and Doppler sonar are to theultra-sonic transducers for measuring the depth and the ship's speed respectively. To measure the depth and speed with a single transducer, it is required to control the ultra-sonic beam to optional direction. In the past, the direction of the transducer itself is varied, but such a method provoked much problems in the mechanical design of the equipment. This paper deals with the method to control beam direciton by the phase control of the plural arrangement of transducers, and the results are studied by a computer simulation. The remarkable results of the study is condensed as follows; 1. The greater the interval of arrangement between transducers, the sharper the radiation pattern is, but in this case, the level of undesired sidelobe is also increased. 2. The control of radiation pattern up to 60 degree can be achieved by an adequate arrangement of more than 10 transducers. 3. It is shown that a simultaneous measurement of both depth and speed can be achieved by alternating directivity of the pulse by the method proposed in this paper.

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평면 배열 안테나를 이용한 수선 지역 형태에 적합한 빔 형성 방법에 관한 연구 (A Study on the Beam forming method suitable receive area shape using planar array antenna)

  • 이봉수;장재철;안도희
    • 한국컴퓨터정보학회논문지
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    • 제8권1호
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    • pp.90-96
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    • 2003
  • 본 논문에서는 N개의 등방성 점원을 수신 지역과 동일한 구조로 배열하고 수신 지역과 동일한 방사패턴을 갖는 배열 구조에 대하여 연구하였다. 배열된 소자 간격은 그레이팅 로브를 피하면서 최적의 특성을 얻기 위하여 반파장 등간격으로 선택하였고, 각 배열 구조의 어레이 팩터를 유도한 후, 방사패턴을 이론적으로 계산하였다. 계산된 특성으로부터 각 평면 배열 안테나의 방사패턴은 수신 지역의 구조와 유사한 빔 특성을 얻을 수 있었다.

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LTCC 공정기술을 이용한 무선랜용 다중대역 칩 안테나 설계 (Design of Multi-band Ceramic Chip Antenna for WLAN using LTCC Technology)

  • 박영호;이용기;이윤도;이상원;천창율
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제53권8호
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    • pp.443-446
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    • 2004
  • In this paper, a multi-band ceramic chip antenna for WLAN(Wireless LAN) applications is designed. The design target is to obtain 0 dBi of coverage gain with omni directional radiation pattern. The antenna is fabricated using Low Temperature Co-fired Ceramic(LTCC) technology. The size of the chip antenna is $2.2{\times}9.65{\times}1.02$mm. The measured antenna gain is 1 dBi at 2.44 GHz and 0.5 dBi at 5.5 GHz. The omni directional radiation pattern for the two operating bands is obtained. The measured bandwidth(S11=-10 dB) are 90 MHz at 2.44 GHz and 1280 MHz at 5.5 GHz respectively

9 GHz 마이크로스티립 패치 안테나의 방사패턴 시뮬레이션 (A Radiation Pattern Simulation of Microstrip Patch Antenna for 9 GHz)

  • 황운택;이헌택;황호웅
    • 한국항해학회지
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    • 제20권4호
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    • pp.129-137
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    • 1996
  • In this paper, we simulated a radiation pattern directivity of microstrip patch antenna for 9[GHz] using the computer. It is analyzed and compared the directivity of field characteristics at two different aspects. One is that of 1-dimension and 2-dimension array, the other is that of a linear and planar array antenna. We tried the constants for the simulation of teflon substrate, dielectric constant ${\varepsilon}r=2.50$, ground plane conductor thickness t=0.03556, substrate height h=0.72188, dielectric loss degree $tan{\delta}$=0.00085, characteristics impedence of line $Zo=50({\Omega})$. The major advantage of microstrip patch antenna is that the arrangement of antenna is associated with the directivity and effectiveness. We have been studied the difference of the radiation pattern of antenna with wave variety through computer simulation.

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마이크로스트립 전송선으로 급전되는 사각형 마이크로스트립 패치 안테나 및 배열 안테나에 관한 해석 및 실험 (Microstrip Line Fed Rectangular Microstrip Patch Antenna and its Array)

  • 박동국
    • 한국광학회:학술대회논문집
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    • 한국광학회 1989년도 제4회 파동 및 레이저 학술발표회 4th Conference on Waves and lasers 논문집 - 한국광학회
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    • pp.152-156
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    • 1989
  • Parameters of a microstrip patch antenna such as the resonant frequency, radiation conductance, and the bandwidth are calculated. The rectangular microstrip patch antenna fed by a microstrip transmission line is fabricated and its resonant frequency, radiation pattern, and input voltage standing wave ratio are measured. The measured resonant frequency for 13.0mm$\times$9.7mm copper clad woven PTFE/glass laminate plate is 9.06Ghz, where the calculative is 9.00Ghz. And the measured vswr shows that the bandwidth of the antenna is 225MHz for vswr less then 2.0 which the calculated quality factor of the patch gives the bandwidth OF 280ghZ. The measured radiation pattern for 5 element as well as 4 element patch array shows less then 4dB deviation in the first side lobes from the designed values for both E and H plane pattern. This diviation is believed to be the power division errors of the power divider.

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운동중인 등방성 플라즈마 층으로 덮인 평면도체 슬랏 안테나의 복사특성 해석 (Analysis of the radiation characteristics from a slot antenna in a plane conductor covered with a moving isotropic plasma layer)

  • 김남태
    • 전자공학회논문지A
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    • 제33A권11호
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    • pp.44-51
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    • 1996
  • The radiation characteristics of a slot antenna in a plane conductor covered with a miving isotropic plasma layer are analyzed. The radiation null which causes distortion in radiation pattern is explainted by the zero of integrand in an asymptotic integral for radiation fields as a function of the plasma parameter and the plasma velocity. Numerical resutls for a radiation null calculated from various plasma and velocity parameters correspond to the results of two-dimensional problem.

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Observational approach on regional lymph node in cutaneous melanomas of extremities

  • Jang, Bum-Sup;Eom, Keun-Yong;Cho, Hwan Seong;Song, Changhoon;Kim, In Ah;Kim, Jae-Sung
    • Radiation Oncology Journal
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    • 제37권1호
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    • pp.51-59
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    • 2019
  • Purpose: We evaluated failure pattern and treatment outcomes of observational approach on regional lymph node (LN) in cutaneous melanoma of extremities and sought to find clinico-pathologic factors related to LN metastases. Material and Methods: We retrospectively reviewed 73 patients with cutaneous melanoma of extremities between 2005 and 2016. If preoperative 18-F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) findings were non-specific for regional LNs, surgical resection of primary tumors with adequate margins was performed without sentinel lymph node biopsy (SLNB) and/or complete lymph node dissection (CLND), irrespective of tumor thickness or size. In patients with suspicious or positive findings on PET/CT or CT, SLNB followed by CLND or CLND was performed at the discretion of the surgeon. We defined LN dissection (LND) as SLNB and/or CLND. Results: With a median follow-up of 38 months (range, 6 to 138 months), the dominant pattern of failure was regional failure (17 of total 23 events, 74%) in the observation group (n = 56). Pathologic LN metastases were significant factor for poor regional failure-free survival (hazard ration [HR] = 3.21; 95% confidence interval [CI], 1.03-10.33; p = 0.044) and overall survival (HR = 3.62; 95% CI, 1.02-12.94; p = 0.047) in multivariate analysis. In subgroup analysis for cN0 patients according to the preoperative PET/CT findings, LND group showed the better trend of LRFFS (log rank test, p = 0.192) and RFFS (p = 0.310), although which is not statistically significant. Conclusion: Observational approach on regional LNs on the basis of the PET/CT in patients with cutaneous melanoma of extremities showed the dominant regional failure pattern compared to upfront LND approach. To reveal regional lymph node status, SLND for cN0 patients may of importance in managing cutaneous melanoma patients.