• 제목/요약/키워드: radiation analysis

검색결과 4,631건 처리시간 0.038초

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
    • /
    • 제33A권11호
    • /
    • pp.44-51
    • /
    • 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.

  • PDF

극저온 시스템의 복사쉴드의 열전달 해석 (Heat Transfer Analysis of the Radiation Shield in Cryogenic Systems)

  • 정은수;장호명;박희찬;양형석
    • 한국초전도ㆍ저온공학회논문지
    • /
    • 제4권1호
    • /
    • pp.124-128
    • /
    • 2002
  • A numerical model to obtain the temperature distribution in a radiation shield of cryogenic systems was proposed. Conformal mapping was used to transform the eccentric physical region of the upper plate to the concentric numerical region. The effects of the thickness of the radiation shield, the emissivities of the vacuum chamber and the radiation shield, and the eccentricity between the centers of the upper plate and the contact area with a cryocooler on the maximum temperature difference in a radiation shield were shown.

보강된 평판구조물의 음향방사특성에 관한 실험적 고찰 (Radiation characteristics on a stiffened plate structure)

  • 강준수;김정태
    • 대한기계학회논문집A
    • /
    • 제22권4호
    • /
    • pp.879-886
    • /
    • 1998
  • It is very important to understand the vibration and noise characteristics of a structure to developed quiet machines and lessen their noise. In this paper, the vibration and sound radiation characteristics of a simple and a bar-stiffened plate have been investigated using numerical and experimental techniques. In numerical process, FEM analysis has been performed for the vibration level ; the time-space squared and averaged velocity and BEM analysis for sound radiation parameters ; sound power and radiation efficiency. In experimental process, FFT signal processing method has been used. While a power from an exiciter is applied to the structure by using a point contact, sound intensity and vibration level has been measured. Based on these two data, the radiation efficiency has been calculated. Results show that the radiation efficiency for the stiffened structure increases compared to the simple plate, due to the extra edges provided by the stiffener.

M&S 기반 반도체소자의 펄스감마선 피해평가 시스템 구축 연구 (A Study on Implementation of a Transient Radiation Effects on Electronics(TREE) Assessment System Based on M&S)

  • 이남호;이승민
    • 전기학회논문지
    • /
    • 제62권7호
    • /
    • pp.969-973
    • /
    • 2013
  • To simulate the effect of high dose-rate radiation on semiconductor devices, device modeling work has been performed especially in the area of photo-current generation by a PIN diode. The resultant analytical values were compared with experimental ones that were specially designed and performed to benchmark the simulation results. Initial results showed 27.85% error between the simulation and the experiment. The error can be further reduced by improvement both in simulation and in related experiments. The developed technique from the study can be applicable to radiation dosimetry and to analysis on the radiation effects in electronics.

국내 수평면 전일사량과 운량 분석 (Analysis of of Horizontal Global Radiation and Cloud Cover in Korea)

  • 조덕기;윤창열;김광득;강용혁
    • 한국태양에너지학회:학술대회논문집
    • /
    • 한국태양에너지학회 2011년도 추계학술발표대회 논문집
    • /
    • pp.124-129
    • /
    • 2011
  • Since the horizontal global radiation and cloud cover are a main factor for designing any solar energy system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of horizontal global radiation and cloud cover in Korea. The data utilized in the investigation consist of horizontal global radiation and cloud cover collected for 27 years(1982.12~2008.12) at measuring stations across the country. The analysis shows that the annual-average daily horizontal global radiation is $3.61kWh/m^2$ and the annual-average daily cloud cover is 5.1 in Korea. We also constructed the contour map of cloud cover in Korea by interpolating actually measured data across the country.

  • PDF

Comparative Analysis of Cosmic Radiation Exposure Dose Due to the Russian Detour Route

  • Hee-Bok Ahn;Jaeyoung Kwak;Junga Hwang
    • Journal of Astronomy and Space Sciences
    • /
    • 제40권2호
    • /
    • pp.59-66
    • /
    • 2023
  • Since the World Health Organization (WHO) officially announced a global pandemic on March 12, 2020, the aviation industry in the world has been experiencing difficulties for a long time. Meanwhile, the Ukraine war broke out in February, and from March 15, domestic airlines must operate air routes bypassing Russian airspace despite the longer flight time. Therefore, as the flight time increases, the cosmic radiation exposure dose of the crew members is also expected to increase. Here we compare the radiation exposure dose between the route doses for the eastern United States and Europe before and after the detour route usage. Through the comparison analysis, we tried to understand how cosmic radiation changes depending on the flight time and the latitude and which one contributes more. We expect that this study can be used for the policy update for the safety management of cosmic radiation for aircrews in Korea.

Toll-like Receptor 5 Agonism Protects Mice from Radiation Pneumonitis and Pulmonary Fibrosis

  • Wang, Zhi-Dong;Qiao, Yu-Lei;Tian, Xi-Feng;Zhang, Xue-Qing;Zhou, Shi-Xiang;Liu, Hai-Xiang;Chen, Ying
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권9호
    • /
    • pp.4763-4767
    • /
    • 2012
  • Radiation pneumonitis and pulmonary fibrosis are the main complications with radiotherapy for thoracic neoplasms, directly limiting the efficient dose in clinical application and currently there are few medicines that effectively function as radioprotectants. However, a TLR5 agonist, CBLB502, was confirmed to have protective efficacy against hematopoietic and gastrointestinal radiation syndromes in mice and primates. This study points to a new direction for protection against thoracic radiation-induced pulmonary syndromes and skin injury by CBLB502. We utilized the TUNEL assay, pathological analysis and immunohistochemistry to obtain evidence thatCBLB502 could alleviate the occurrence of radiation pneumonitis and pulmonary fibrosis as well as radiation-induced skin injury. It may thus play a promising role in facilitating clinical radiotherapy of thoracic neoplasms.