• Nuclear Engineering and Technology
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• v.22 no.4
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• pp.410-415
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• 1990

Prompt fission neutron energy spectrum as a function of energies of neutron inducing fission has been calculated en the basis of the Madland-Nix(MN) model. The resultant spectra have been weighted to excitation functions of $^{27}$ Al(n, $\alpha$), $^{32}$ S(n, p) and $^{115}$ In(n, n') threshold reactions in order to get the average cross sections and then spectral indices which are defined as the average cross section ratio for two selective threshold reactions among the above three. It is appeared that spectral indices together with the neutron spectra are varying with energies of neutron inducing fission. This may indicate that the prompt fission neutron energy spectrum can be determined by measuring experimentally the spectral index.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.594-599
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• 1998

출력 운전중 원자로 건물내의 중성자 에너지 스펙트럼의 분포를 살펴보기 위해 중성자 스펙트럼 측정을 수행하였다. 영광4흐기 원자로 건물내 100ft 상에서 4곳, 122ft 상에서 4곳, 144 ft 상에서 8곳을 Bonner Multisphere Spectrometer(BMS) 시스템을 이용하여 중성자 스펙트럼을 측정하였다. BMS는 Cf-252 선원으로 교정하였으며 측정된 데이터는 BUNKI 코드를 이용하여 unfolding 하여 에너지 스펙트럼을 얻었다 분석 결과 100 ft의 경우 평균 중성자 에너지는 0.100 ~ 1.954 MeV, Fluence는 4.913$\times$$10^2$ ~ 1.478$\times$$10^4$ n/$\textrm{cm}^2$, 선량율은 0.56 ~ 289.37 mrem/hr의 분포를, 122 ft의 경우 평균 중성자 에너지는 0.122 ～ 0.320 MeV, Fluence는 4.586$\times$$10^{0}$ ~ 7.743$\times$$10^3$ n$\textrm{cm}^2$, 선량율은 0.05 ~ 201.46 mrem/hr의 분포를, 144 ft의 경우 평균 중성자 에너지는 0.062 ~ 0.578 MeV, Fluence는 7.922$\times$$10^{0}$ ~ 1.703$\times$$10^2$ n/$\textrm{cm}^2$, 선량율은 0.10 ~ 45.58 mrem/hr의 분포를 보였다.

• Nuclear Engineering and Technology
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• v.15 no.4
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• pp.280-285
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• 1983

Effects of fission neutron spectra in the reactor calculations have been analysed through applications of several cases of spectra in the criticality calculations of fast critical assemblies. They were the application of Maxwellian or Watt-Cranberg type formulae, of region dependent spectrum, of composition dependent spectrum, of fission transfer matrix, and the effects due to the selection of nuclear temperature in Maxwellian formula.

• Journal of Radiation Protection and Research
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• v.38 no.3
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• pp.143-148
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• 2013

Operational nuclear facilities such as nuclear power plants and particle accelerators show various neutron spectra according to the type of facilities and specific position. Necessities of neutron dose management and neutron monitoring for radiation protection of radiation workers in such a kind of facilities have continuously increased in recent years. Bonner sphere spectrometers are widely used for measurement of neutron spectra. Data on response function of neutron detector, default neutron spectra and count rates of Bonner sphere spectrometer are required to obtain unfolded neutron spectra in specific workplaces. In this study, we carried out measurement of neutron spectra produced in MC50 cyclotron using Bonner sphere spectrometer with LiI scintillation detector. Additionally, we estimated quantitative data on neutron flux, mean neutron energy and ambient dose equivalent rate according to the incident proton energies and positions in MC50 cyclotron.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.11a
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• pp.3-6
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• 2007

현재 우리나라는 원자력 발전에 대한 의존도가 매우 높고 그 기술 또한 우수하다. 그러나 중성자 스펙트럼을 사용하여 폭발물 탐지를 위한 시스템 개발 기술은 미흡한 실정이다. 본 논문은 신경망(Neural Networks)을 한국 원자력 연구소 중성자 스펙트럼 패턴을 분류하는 시스템에 적용하였다. 데이터 획득방법을 달리하여 두 개의 신경망을 구현하였고 그 결과를 분석하여 보았다. 먼저 폭발물에 다량 포함되어 있는 C(Carbon), N(Nitrogen), O(Oxygen) 3개의 물질을 중심으로 중성자 스펙트럼을 분석하였다. 다른 하나는 중성자 스펙트럼을 전체 영역으로 획득한 데이터를 바탕으로 신경망을 구현하여 인식률을 확인하였다. 실험결과 전자의 경우 62.5%의 인식률을, 후자의 경우 신경망은 83.48%의 인식률을 나타내었다.

• 대한방사선방어학회:학술대회논문집
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• 2011.11a
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• pp.252-253
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• 2011

• Nuclear Engineering and Technology
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• v.11 no.2
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• pp.133-136
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• 1979

In the paper it is proposed to use Ge(Li) detectors in determining fast neutron spectra. The spectrum at 691.4 KeV which is produced by the internal conversion of Ge nuclei being broadened by the coincident ionization energy deposited by recoil Ge atoms is proposed to be analysed in estimating the fast neutron spectra.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10c
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• pp.451-454
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• 2007

본 논문은 한국 원자력 연구소 중성자 스펙트럼 패턴을 분류하는 시스템에 신경망(Neural Networks)을 적용하였다. 중성자 스펙트럼 분석시 3개의 신경망을 하나로 결합하여 각 신경망의 인식률을 확인하였다. 신경망1은 폭발물 판별을, 신경망2는 폭발물의 종류를, 신경망3은 비 폭발물 종류를 구별하도록 시스템을 설계하였다. 중성자 스펙트럼을 통해 실험한 결과 신경망1은 83.48%를, 신경망2는 84.6%를, 신경망3은 91.67%의 인식률을 얻어 본 논문에서 제안한 시스템의 우수성을 입증하였다.

• Analytical Science and Technology
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• v.5 no.1
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• pp.57-61
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• 1992

For the neutron spectrum measurement, $^6Li$ neutron spectrometer system is installed. The characteristic of the $^6Li$ detector are investigated using a $^{137}Cs$ and $^{207}Bi$ point source, and the neutron capture peaks and the pulse height spectrum using an $^{214}Am-Be$ neutron source are measured. Furthermore, the pulse height spectrum for the irradiation time variation from the (214)^Am-Be neutron source, and for the distance variation between detector and source, and the threshold variation of discriminator are measured.

• Analytical Science and Technology
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• v.5 no.4
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• pp.367-372
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• 1992

In order to measure the energy spectrum of a radioactive neutron source, the pulse shape discrimination (PSD) system with organic scintillator, NE-213, was characterized by using some of the gamma ray sources and neutron source, Am-Be. The figure of merit of the rise time spectrum of AmBe source measured by this system was about 1.13. This value agrees well with the value of 1.3 which is measured for monoenergetic source, $^{12}C(d,\;n)^{13}N$. The results of present experiment for performance test of NE213-PSD system will provide the useful technique to measure the spectrum of neutron-gamma mixed field and to establish the neutron energy spectrum and flux density standards.