• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.336-336
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• 2012

수명 측정법과 동시 계수 도플러 넓어짐 양전자 소멸 분광법으로 p형과 n형 실리콘 시료에 0, 3.98 MeV 에너지를 가진 $0.0{\sim}20.0{\times}10^{13}$ protons/$cm^2$ 양성자 빔 조사에 의한 결함을 측정하여 실리콘 결함 특성에 대하여 조사하였다. 양전자와 전자의 쌍소멸로 발생하는 감마선 스펙트럼의 전자 밀도 에너지를 수리적 해석 방법인 S-변수와 열린 부피 결함에 대한 측정법으로서 양전자 수명 ${\tau}1$과 ${\tau}2$, 이에 따른 밀도 I1과 I2를 사용하여, 시료의 구조 변화를 측정하였다. 본 연구에서 측정된 S-변수와 양전자 수명은 시료에 조사된 양성자의 빔 에너지에 따라 변화하기보다 양성자 조사량의 변화에 따라 결함이 증가하였으며, 양전자 수명 측정과 같은 경향을 보여준다. SRIM의 결과로써, 양성자 조사 에너지에 따른 Bragg 피크 때문에 양성자는 시료의 특정 깊이에 주로 결함을 형성하여 시료 전체에는 결함으로 잘 나타나지 않기 때문이다. 빔의 조사량에 따른 결함의 영향이 더 큰 것으로 나타났다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.97-98
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• 2005

양성자 조사법에 의하여 고속 전력용 다이오드를 제작하기 위하여 punch-through 다이오드에 다양한 조건으로 양성자를 조사하였다. 동일한 소자에 전자선을 조사한 소자와 속도 향상을 위한 공정이 행하여지지 않은 동일한 소자 각각의 특성을 비교 분석하였다. 양성자 주입은 주입 에너지를 1 MeV 와 1.3 MeV로, 각 에너지 조건에서 도즈를 $1\times10^{12}cm^{-2}$, $1\times10^{13}cm^{-2}$로 변화 시켰다. 분석 결과 양성자 주입된 소자에서 역방향 회복시간은 최소 소자의 약 45%, 전자선이 조사된 소자에 비하여 약 73 %의 값으로 향상시킬 수 있었으며 역방향 항복 전압과 순방향 저항은 처리되지 않은 소자와 전자빔이 조사된 시편들의 값과 비슷한 값을 나타내었다.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.287-287
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• 2011

동시 계수 도플러 넓어짐 양전자 소멸 분광법으로 n, p형 Cz-Si의 시료에 양성자를 0, 4 MeV 에너지와 조사량의 변화에 의한 결함을 측정하였으며, 고체 구조 특성에 대하여 조사하였다. 양전자와 전자의 쌍소멸로 발생하는 511 keV 감마선 스펙트럼의 수리적 해석 방법인 S-변수와 W-변수를 사용하여, 구조 변화를 측정하였다. 양성자 조사에너지의 세기에 따라 결함이 증가하였으며, 양성자의 조사량의 변화에 대하여는 큰 변화가 없었다.

• Journal of agricultural medicine and community health
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• v.13 no.1
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• pp.26-31
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• 1988

An epidemiological study was undertaken to evaluate the prevalence of E. vermicularis infestation among children in primary schools and orphanages. A total of 2,966 children in primary schools and orphanages was examined for F. vermicularis by means of cellotape anal swab technique. The purpose of the present studies is to determine the prevalence of enterobiasis among children and to make a comparison with the rate of infestation by survey areas. The result could be summarized as follows : 1) The egg positive rate of cellotape anal swab method was 16.3% out of 2,966 children. 2) The egg positive rate of urban area was 6.9% out of 1,144 children and the egg positive rate of rural area was significantly higher than that of urban area. 3) The egg positive rate of boys and girls were 15.7% out of 1,528 children and 16.9% out of 1,438 children. 4) The egg positive rate of primary schools, orphanages and mental retardation child group was 11.3% (out of 2,412), 32.7% (out of 416) and 55.1% (out of 138) respectively. There was noted a tendency of decrease in prevalence by increase of the age.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.623-625
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• 2022

In this paper, the proton induced attenuation characteristics were evaluated for 5 types of commercial single-mode optical fibers using a proton accelerator. The proton beam used in the irradiation test has a high energy of 100 MeV class, and the test was performed by setting the uniformity of the beam irradiation area to 10% or less. According to the type of optical fiber (internal material, impurities), the radiation induced attenuation by the proton irradiation showed a noticeable difference.

• Journal of the Korean Vacuum Society
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• v.20 no.5
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• pp.367-373
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• 2011

It is described that the proton beam induces micro defects and electronic deep levels in Cz single crystal silicon. Enhance signal-to-noise ratio, Coincidence Doppler Broadening Positron Annihilation Spectroscopy has been applied to study of characteristics of p type and n type silicon samples. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The samples were exposed by 4.0 MeV proton beams ranging from 0 to ${\sim}10^{14}$ ptls. The S-parameter values were increased as increasing the irradiated proton beam, that indicated the defects generate more.

• Journal of the Korean Vacuum Society
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• v.21 no.5
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• pp.225-232
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• 2012

It is described that the proton beam induceds micro-size defects and electronic deep levels in n or p type single crystal silicon. Positron lifetime and Coincidence Doppler Broadening Positron Annihilation Spectroscopy were applied to study of characteristics of p type and n type silicon samples. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The samples were exposed by 3.98 MeV proton beams ranging between 0 to ${\sim}10^{14}$ particles. The S-parameter values strongly depend on the irradiated proton beam, that indicated the defects generate more. Positron lifetime shows that positrons trapped in vacancies and lifetime ${\tau}_2$ increased according to proton irradiation.

• Journal of the Korean Vacuum Society
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• v.18 no.6
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• pp.447-452
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• 2009

Enhance signal-to-noise ratio, Coincidence Doppler Broadening positron method has been applied to study of characteristics of BaSrFBr:Eu film sample. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The films were exposed by 0, 3, 5, and 7.5 MeV proton beams ranging from 0 to $10^{13}$ ptls. The S-parameter values were increased as increasing the exposed time and the energies, that indicated the defects generate more.

• Parasites, Hosts and Diseases
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• v.21 no.2
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• pp.246-256
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• 1983

As epidemiological parameters of human paragonimiasis, the positive rates of intradermal test and the sputum/stool ekaminations have long been employed in population surveys. However, both the specificity of the intradermal test and the sensitivity of sputumjstool examination have been gradually declined as the endemicity was lowered; thus the gap between above two parameters widened. In such context, the development of a new epidemiologic parameter or tool which makes it possible to accurately discriminate the active paragonimiasis cases was necessary. In the present study, the detection rate of Paragonimus-speclac IgG antibody by micro-ELISA was evaluated as an indicator of epidemiologic status of human paragonimiasis in a population. A total of 4, 285 students and inhabitants living in Bukpyeong Myeon and Bukil Myeon, Haenam Gun, Jeonlanam Do was surveyed in October, 1983 by intradermal test first. Out of them, 244 cases (5.7%) were found positively reacted to VBS antigen of F. westermani. Out of 168 positive reactors, 7 cases (4.2%) were egg positive either by two times of sputum examination or by one stool examination. That indicated that only 0. 16% of total surveyed were confirmed as active paragonimiasis by egg detection. When sera collected from 239 positive reactors of Intradermal test were tested by micro-ELISA for their specific IgG antibody, 40 cases(16.7%) were found to be positive. All of 7 egg positive cases were again positive for specific IgG antibody. Among remaining 232 intradermal test positive cases, 33 cases were positive for IgG antibody. In contrast to those, none of 42 positive reactors to intradermal test for Cloncrchis and of 128 intradermal test negative cases showed positive for Paragcnimus-specIfic IgG antibody. The rate of specific IgG antibody as detected by micro-ELISA appeared to be increased with the wheal size of the intradermal test. When the wheal sixte was over 13mm in diameter, about 50% of them were positive for specific IgG antibody. Thirty-one specific antibody positive cases were clinically evaluated by laboratory examinations (repeated sputum examination, peripheral eosinophil count and chest roentgenogram) and by history taking. Out of them 24 cases were associated with one or more positive laboratory findings: thus considered as active paragonimiasis cases. Out of 7 lab. finding-free cases 3 revealed past history of typical paragonimiasis symptoms, suggesting that they were in chronic or in convalescent stages. The remaining 4 cases were considered as either mild or ectopic infection cases; the possibility of cross-reaction with other helminthiases could not be ruled out. From the above results, it was inferred that the detection of Paragonimus-specIfic IgG antibody by micro-ELISA was very much helpful in detecting the active cases as well as in proper evaluation of the endemicity of human paragonimiasis in a population. The convenience of mass haildling of sera in micro-ELISA was considered another superiority as an epidemiologic tool.

• Bulletin of the Korean Space Science Society
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• 2004.04a
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• pp.47-47
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• 2004

사이클로트론 가속기를 이용한 양성자 우주환경의 모사시험이 수행되었다. 모사시험에 사용된 사이클로트론은 양성자를 약 106-108protons/$\textrm{cm}^2$/s의 선속에서 200MeV까지 가속할 수 있다. 가속된 양성자는 우주에서 사용될 전자 소자에 입사되었으며, 양성자 조사에 의한 소자의 누적 반응과 순간 반응이 모두 관찰되었다. 주된 순간 반응은 저장된 데이터의 변화였으나, 간헐적인 기능 정지 현상도 관찰되었다. 누적 반응은 소자 내에서 소모되는 전류의 증가로 나타났다. (중략)