• 항공우주시스템공학회지
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• 제10권4호
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• pp.105-114
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• 2016

국가간의 지역충돌, 영토, 보호, 대테러 그리고 국제 무역 흐름에 직면한 현 세계는 항공기 수출, 부대파견 및 해외 주둔에 연관되어 감항인증 업무가 증가될 수 있다. 주권 국가의 위치와 책임을 최소화하기 위해서 외국 군 당국사이의 감항인증 절차를 확립하는 것은 중요하다. 이 연구는 항공기 개발 및 운영을 위한 비행 안전을 확보하기 위한 인정 파트너 사이의 군 감항 인정을 연구하였다. 이 논문은 감항 당국의 역할, 감독능력, 생산절차 및 인증의 소개로 미국 및 유럽 군 당국의 인정의제를 분석하였다. 군 당국인정인제를 기본으로, 다른 외국 군당국과 한국군감항당국에 의해 요구되는 규정활동을 감소할 수 있다.

• Nuclear Engineering and Technology
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• 제46권3호
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• pp.313-342
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• 2014

A Nuclear Energy Agency (NEA), Organization for Economic Co-operation and Development (OECD) benchmark for Uncertainty Analysis in Modeling (UAM) is defined in order to facilitate the development and validation of available uncertainty analysis and sensitivity analysis methods for best-estimate Light water Reactor (LWR) design and safety calculations. The benchmark has been named the OECD/NEA UAM-LWR benchmark, and has been divided into three phases each of which focuses on a different portion of the uncertainty propagation in LWR multi-physics and multi-scale analysis. Several different reactor cases are modeled at various phases of a reactor calculation. This paper discusses Phase I, known as the "Neutronics Phase", which is devoted mostly to the propagation of nuclear data (cross-section) uncertainty throughout steady-state stand-alone neutronics core calculations. Three reactor systems (for which design, operation and measured data are available) are rigorously studied in this benchmark: Peach Bottom Unit 2 BWR, Three Mile Island Unit 1 PWR, and VVER-1000 Kozloduy-6/Kalinin-3. Additional measured data is analyzed such as the KRITZ LEU criticality experiments and the SNEAK-7A and 7B experiments of the Karlsruhe Fast Critical Facility. Analyzed results include the top five neutron-nuclide reactions, which contribute the most to the prediction uncertainty in keff, as well as the uncertainty in key parameters of neutronics analysis such as microscopic and macroscopic cross-sections, six-group decay constants, assembly discontinuity factors, and axial and radial core power distributions. Conclusions are drawn regarding where further studies should be done to reduce uncertainties in key nuclide reaction uncertainties (i.e.: $^{238}U$ radiative capture and inelastic scattering (n, n') as well as the average number of neutrons released per fission event of $^{239}Pu$).

• 대한교통학회지
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• 제29권3호
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• pp.115-122
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• 2011

이 논문은 자동차의 급제동시 발생되는 스키드마크(skid mark, 활주거리)를 통해 제동직전 속도(Pre-braking Speed)를 정확히 산정하기 위한 방법론을 제시하고자 한다. 운전자는 전방에 위급한 상황이 전개되거나 불의의 사고에 처하게 되었을 경우 통상 급제동조치를 취하게 되며, 정지거리에 따라 사고를 당할 수도 있다. 자동차의 정지거리에 있어서 영향을 끼치는 요인은 운전자의 인지반응시간, 자동차 제동장치의 성능, 노면의 상태 등을 꼽을 수 있으나, 가장 중요한 요인은 제동직전 속도(Pre-Braking Speed)라고 할 수 있다. 현재 교통사고의 조사분야에서는 skid mark의 길이에 근거한 활주직전 속도(Preskidding Speed)를 산정하여 과속 여부를 판단하고 있으나, 정확한 사고원인 규명을 위해서는 불완전제동시간 동안 감속된 속도를 고려한 제동직전 속도의 산정이 필요할 것으로 판단된다. 따라서, 본 연구에서는 교통사고시 자동차의 정확한 속도정보를 산정하기 위한 방법을 제안하고자 하며, 또한 이 연구가 향후 교통안전차원에서 자동차의 특성을 이해하는데 있어서 일조할 수 있기를 기대한다.

• 한국환경보건학회지
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• 제38권1호
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• pp.18-30
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• 2012

Objectives: The purpose of this study was to estimate the exposure level to extremely low frequency-magnetic fields (ELF-MF) among a selected Korean population using 24-hour personal exposure measurement. Methods: Participants were randomly selected for the measurement of MF exposure under the assumption that the subjects are representative of the overall Korean population. Levels of personal exposure to MF were measured according to the subject's daily activities. Results: The 24-hour time-weighted average (TWA) of 250 participants was $1.56{\pm}4.56$ mG (GM, GSD: 0.79, 2.46 mG). Personal exposure levels for females were higher than for males. The highest personal exposure level was shown in the age group between 20-60 years old. Personal exposure levels according to job category were higher for the non-occupational group than for the occupational group. Conclusions: Our results showed MF exposure exceeding 2 mG per day among 11.3% of the Korean population, indicating a somewhat higher percentage compared to the EMF RAPID Program's results for the U.S population.

• Journal of Radiation Protection and Research
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• 제41권2호
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• pp.155-159
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• 2016

Background: Nuclear reactors produce a great number of antielectron neutrinos mainly from beta-decay chains of fission products. Such neutrinos have energies mostly in MeV range. We are interested in neutrinos in a region of keV, since they may take part in special weak interactions. We calculate reactor antineutrino spectra especially in the low energy region. In this work we present neutrino spectrum from a typical pressurized water reactor (PWR) reactor core. Materials and Methods: To calculate neutrino spectra, we need information about all generated nuclides that emit neutrinos. They are mainly fission fragments, reaction products and trans-uranium nuclides that undergo negative beta decay. Information in relation to trans-uranium nuclide compositions and its evolution in time (burn-up process) were provided by a reactor code MVP-BURN. We used typical PWR parameter input for MVP-BURN code and assumed the reactor to be operated continuously for 1 year (12 months) in a steady thermal power (3.4 GWth). The PWR has three fuel compositions of 2.0, 3.5 and 4.1 wt% $^{235}U$ contents. For preliminary calculation we adopted a standard burn-up chain model provided by MVP-BURN. The chain model treated 21 heavy nuclides and 50 fission products. The MVB-BURN code utilized JENDL 3.3 as nuclear data library. Results and Discussion: We confirm that the antielectron neutrino flux in the low energy region increases with burn-up of nuclear fuel. The antielectron-neutrino spectrum in low energy region is influenced by beta emitter nuclides with low Q value in beta decay (e.g. $^{241}Pu$) which is influenced by burp-up level: Low energy antielectron-neutrino spectra or emission rates increase when beta emitters with low Q value in beta decay accumulate Conclusion: Our result shows the flux of low energy reactor neutrinos increases with burn-up of nuclear fuel.

• 한국조리학회지
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• 제15권3호
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• pp.112-127
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• 2009

2007년 현재 한 미 FTA 협상 결과에 따라 미국산 수입 쇠고기의 개방이 본격화되면서 국내 외식시장의 변화가 예상되고 있다. 이에 국내 외식시장은 '쇠고기 원산지 표시제의 정착'과 '국내산 한우와 수입 쇠고기에 대한 소비자 니즈의 충족'이라는 당면과제를 안고 있다. 이와 같이 조사 분석된 연구 결과를 요약하면 다음과 같다. 첫째, 일반음식점의 쇠고기 원산지 표시에 대한 소비자 인식 수준은 비교적 낮은 것으로 나타났다. 둘째, 수입 쇠고기를 선호하는 이유는 한우에 비해 맛은 떨어지지만 가격이 상대적으로 저렴하기 때문인 것으로 나타났으며, 일반음식점에서 판매하는 국내산 한우에 대한 불신감이 큰 것으로 분석되었다. 셋째, 국내산 한우는 맛의 우수성, 안전성, 신선도에서 높은 평가를 받고 있는 반면, 수입 쇠고기는 모든 속성에서 보통 수준 이하의 낮은 평가를 받고 있었다. 이와 같은 조사 결과를 토대로 판단해 볼 때, 쇠고기의 원산지 표시제에 대한 일반음식점의 올바른 인식과 원산지 표시제도의 정착을 통해 소비자들이 믿고 먹을 수 있는 외식 환경이 조성되어야 하며, 국내산 한우와 수입 쇠고기에 대한 소비자 니즈를 충족시키기 위한 노력이 있어야 할 것이다.

• 대한가정학회지
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• 제46권4호
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• pp.83-96
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• 2008

The purpose of this study is to grasp the opinion of Korean feminine seniors on the life support appliances for their healthy ageing: medication dispenser, video phone, activity monitor and sleep monitor. The focus group interviews, asking the usability of the appliances, were answered by each 6 feminine seniors of more than 65 years, residing in Corvallis of U.S.(group I), Cheongju(group II), and Ulsan(group III) of Korea. The results are as follows. (1) The medication dispenser proved to be very useful to all the respondents. All the seniors, who take more than one medicine a day, felt it helpful that the medication dispenser makes them to take medicines at fixed time. In addition, they hoped the medicine envelope to be developed for the dispenser use by the supply side. (2) The seniors showed interest in the manner the video phone works; to work by the voice, rather than by the finger. They expressed the hope of the video phone to display the communication contents, in consideration of their weakening hearing. (3) The seniors who live alone, especially, felt intimacy to the activity monitor, thinking as if some helpers were beside them. The fact that it can send emergency calls immediately when situations happen, gave the seniors emotional safety as a patron. (4) The sleep monitor, although essential to the serious cases without moving ability, was proved less necessary to the healthy seniors. They expressed the hope of this appliance to be evolved for the use with the mattress without bed.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년 춘계학술발표대회 논문집
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• pp.155-160
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• 2009

Safety of residents could be considered and then increased when we plan, design, and operate a city. In Korea, CPTED (Crime Prevention through Environmental Design) is currently being applied to new towns. However, it is not systemized and neither efficient, for there are no constraint provisions, and the foreign cases are not specifically customized to the current situation of the country. This means, the introduction of CPTED is an indispensable fact, but there are limits to the budget aids and actual application, for there is no legal base to support it. This study, therefore, aims to find the limits from analyzing related laws and regimes, administrative regulations, and applied cases, and to deduct improvement plans based on examined foreign cases. In this Study, the supporting system of foreign CPTED related laws and regulations was analyzed around the cases of England and U.S.A, and based on that information, the present condition and limits of CPTED related laws and regulations of Korea were deducted. As a result of this study, there were no constraint provisions to apply the design guidelines to actual planning, and there were limits on backup aid and actual application due to the lacking of analyzing the relevant area. Also, an acceptable framework must be arranged by the revision of laws and ordinances to compel the system, and link it with the CPTED certification system which will revitalize the whole system.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2002년도 춘계 국제 학술대회
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• pp.40.1-43
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• 2002

The purpose of this study was to evaluate a new sampling and analytical method for the determination of hexavalent chromium, Cr(VI) in mist from field plating operation. The Procedures of this new method (Shin & Paik's Method) are as the following: Airborne hexavalent chromium is collected on polyvinyl chloride (PVC) filter according to the National Institute for Occupational Safety and Health (NIOSH) Method 7600, and the filter sample is placed in a screw-capped vial and soaked with 2％ NaOH/3％ Na₂CO₃ solution immediately after sampling. The Cr(VI) sample is analyzed by ion chromatography/visible spectrophotometry (IC/VS) according to the U.S. Environmental Protection Agency (EPA) Method 218.6. The airborne Cr(VI) concentrations measured by this method were compared with those determined by three reference methods: One (NIOSH/EPA Method) consisted of sampling airborne Cr(VI) on PVC filters and storing the sample filters in screw-capped vials according to the NIOSH method, and analyzing Cr(VI) in samples using IC/VS according to the EPA method. The second method (Impinger Method/NaHCO₃) consisted of absorbing airborne Cr(VI) into 0.02 MN/sub a/Hco₃ solution in midget impinger, and analyzing the Cr(VI) in samples using IC/VS. The third method was the OSHA Method Id-215. Using these four different methods, four replicates of air samples were collected at an electroplating process and analyzed simultaneously. Two-way ANOVA and Paired t-test were used to test difference among values determined by the methods. There was no significant difference and a strong correlation (r/sup 2/=0.99) between Cr(VI) concentrations measured by the shin & Paik's Method and an impinger method (p＞0.05). However, Cr(VI) concentrations determined by Shin & Paik's Method were Significantly different form those by the NIOSH/EPA Method (p＜0.05) or the OSHA method (p＜0.05). The Cr(VI) concentrations of Shin & Paik's Method were Significantly higher than those of the NIOSH/EPA Method or the OSHA method. We concluded that the Shin & Paik's Method could prevent Cr(VI) losses caused by reduction and give more reliable results of airborne Cr(VI) concentrations in work environments.

• 대한기계학회논문집A
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• 제34권8호
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• pp.1113-1118
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• 2010

차량의 내장부품 설계에 있어 내장 부품의 탑승자 보호를 위한 FMVSS 201 법규에 따른 FMH 충격성능 만족을 위한 충격흡수구조 설계 방법이 필요하다. 충격흡수구조 설계 과정에 있어 FMH 충격 성능은 헤드라이닝의 타격 위치 및 헤드폼의 접근각에 따라 위치별로 각각 다르게 설정되며, FMH 충격 흡수부재는 위치에 따른 차체의 강성 및 상관부품을 고려하여 각 타격 위치에 따른 적절한 충격 흡수 성능을 가져야 하며 차체 강성의 변화를 고려한 효율적인 설계 방법이 필요하다. 본 연구에서는 충격 흡수구조 설계 과정에 있어 초기 설계안에 대한 충격 강도 검토의 시간을 줄이기 위해 전차량 시뮬레이션에서 수행하던 FMH 충격흡수부재 설계를 단위 모델의 압궤 시뮬레이션을 통해 진행함으로써 보다 빠르고 효율적으로 타격 위치별 적합한 충격 흡수구조를 설계하는 방법을 검토하였다.