• Title/Summary/Keyword: Radiation Pattern

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

  • Kim, Jae-hyo;Bhang, Yeon-hee;Do, Ha-yoon;Ahn, Jun-mo;Kim, Kwan-il;Lee, Beom-joon;Jung, Sung-ki;Jung, Hee-jae
    • The Journal of Internal Korean Medicine
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    • v.38 no.1
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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.

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

  • Seo Heekyung;Ryu Yangseon;Choi Joonsoo;Hahn Kwang-Soo;Kim Seongcheol
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.3
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    • pp.133-147
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    • 2005
  • Various types of ray-tracing methods are used to predict the quantity measures of radiation illumination, the uniformity of illumination, radiation performance of LCD BLU(Hack-Light Unit). The uniformity of radiation illumination is one of the most important design factor of BLU and is usually controlled by the diffusive-ink pattern printed on the bottom of light-guide panel of BLU. Therefore it is desirable to produce an improved (ideally, the optimal) ink pattern to achieve the best uniformity of radiation illumination. In this paper, we applied the Welder-Mead simplex-search method among various direct search method to compute the optimal ink pattern. Direct search methods are widely used to optimize the functions which are often highly nonlinear, unpredictably discontinuous, and nondifferentiable, The ink-pattern controlling the uniformity of radiation illumination is one type of these functions. In this paper, we found that simplex search methods are well suited to computing the optimal diffusive-ink pattern. In extensive numerical testing, we have found the simplex search method to be reasonably efficient and reliable at computing the optimal diffusive-ink pattern. The result also suggests that optimization can improve the functionality of simulation tools which are used to design LCD BLU.

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

  • 신형일
    • Journal of the Korean Institute of Navigation
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    • v.3 no.2
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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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A Study on the Beam forming method suitable receive area shape using planar array antenna (평면 배열 안테나를 이용한 수선 지역 형태에 적합한 빔 형성 방법에 관한 연구)

  • 이봉수;장재철;안도희
    • Journal of the Korea Society of Computer and Information
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    • v.8 no.1
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    • pp.90-96
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    • 2003
  • In this paper, arranged the isotropic point source of N number with the structure which is identical with the receive area. And against the array structure which has the radiation pattern which is identical with the receive area it researched. The arranged the element space flees grating lobe and in order to set the characteristic of optimum with half-wave equally space it selects. After inducing the array factor of each array structure, it calculated a radiation pattern. As a result of, the radiation pattern of the each Planar array antenna with structure of the receive area was similar and the possibility of getting an beam characteristic it was.

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

  • 박영호;이용기;이윤도;이상원;천창율
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.8
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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

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

  • 황운택;이헌택;황호웅
    • Journal of the Korean Institute of Navigation
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    • v.20 no.4
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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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Microstrip Line Fed Rectangular Microstrip Patch Antenna and its Array (마이크로스트립 전송선으로 급전되는 사각형 마이크로스트립 패치 안테나 및 배열 안테나에 관한 해석 및 실험)

  • 박동국
    • Proceedings of the Optical Society of Korea Conference
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    • 1989.02a
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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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Analysis of the radiation characteristics from a slot antenna in a plane conductor covered with a moving isotropic plasma layer (운동중인 등방성 플라즈마 층으로 덮인 평면도체 슬랏 안테나의 복사특성 해석)

  • 김남태
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.11
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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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    • v.37 no.1
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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.

Design of Tapered Slot Antenna for UWB Communications (UWB 통신을 위한 테이퍼드 슬롯 안테나 설계)

  • Kim, Sun-Woong;Choi, Dong-You
    • Smart Media Journal
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    • v.4 no.4
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    • pp.64-69
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    • 2015
  • In this paper, we have proposed a tapered slot antenna for UWB communication system. The tapered slot antenna has directional radiation and broad bandwidth. Proposed tapered slot antenna is designed using Ansys Inc. HFSS and its VSWR, return los, and radiation pattern is analyzed. Operating band of the antenna were satisfied -10 dB S11 and $VSWR{\leq}2$ in 2.7 ~ 4.8 GHz band. The radiation pattern of the antenna is showed in E-plane (YZ plane) and the H-plane (XZ plane) and the highest gain of 7.3 dBi is seen at 4.5 GHz. Therefore, proposed tapered slot antenna has wide bandwidth characteristic and directional for location awareness.