• Nuclear Engineering and Technology
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• v.43 no.6
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• pp.583-592
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• 2011

The radiological characteristics for waste classification were assessed for neutron-activated decommissioning wastes from a CANDU reactor. The MCNP/ORIGEN2 code system was used for the source term analysis. The neutron flux and activation cross-section library for each structural component generated by MCNP simulation were used in the radionuclide buildup calculation in ORIGEN2. The specific activities of the relevant radionuclides in the activated metal waste were compared with the specified limits of the specific activities listed in the Korean standard and 10 CFR 61. The time-average full-core model of Wolsong Unit 1 was used as the neutron source for activation of in-core and ex-core structural components. The approximated levels of the neutron flux and cross-section, irradiated fuel composition, and a geometry simplification revealing good reliability in a previous study were used in the source term calculation as well. The results revealed the radioactivity, decay heat, hazard index, mass, and solid volume for the activated decommissioning waste to be $1.04{\times}10^{16}$ Bq, $2.09{\times}10^3$ W, $5.31{\times}10^{14}\;m^3$-water, $4.69{\times}10^5$ kg, and $7.38{\times}10^1\;m^3$, respectively. According to both Korean and US standards, the activated waste of the pressure tubes, calandria tubes, reactivity devices, and reactivity device supporters was greater than Class C, which should be disposed of in a deep geological disposal repository, whereas the side structural components were classified as low- and intermediate-level waste, which can be disposed of in a land disposal repository. Finally, this study confirmed that, regardless of the cooling time of the waste, 15% of the decommissioning waste cannot be disposed of in a land disposal repository. It is expected that the source terms and waste classification evaluated through this study can be widely used to establish a decommissioning/disposal strategy and fuel cycle analysis for CANDU reactors.

• Journal of agricultural medicine and community health
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• v.46 no.3
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• pp.171-185
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• 2021

배경: 2015년 한국의 중동호흡기증후군 유행에서 지역간 치명률의 차이는 극명하였다. 이 연구는 대전 클러스터와 다른 지역 간의 치명률의 관련된 일반적 특성 및 역학적 요인을 밝히고저 하였다. 방법: 입원병원 소재지를 기준으로 대전과 타 지역으로 구분하여 관련변수에 따른 카이제곱검정 및 피셔정확검정 등으로 분석하였다. 대전과 다른 지역의 치명률(CFR)의 차이와 관련된 요인을 분석하기 위하여 단변량 및 다변량 로지스틱 회귀분석를 실시하였다. 결과: 모형 I에서는 65세 이상 연령군일수록 7.12배(95% CI 2.33-21.8)(p=0.001), 동반질환이 있는 경우 10.29배(95% CI 2.94-36.06)(p<0.001), 잠복기가 7일 이하인 경우가 8.55배(95% CI 2.54-26.7), 입원기간이 17일 이하인 경우 10.08배(95% CI 2.99-31.9)(p<0.001) 등이었으며, 모형 II에서는 65세 이상 연령군일수록 5.34배(95% CI 1.65-17.2)(p=0.005), 잠복기가 7일 이하인 경우가 6.70배(95% CI 1.96-22.89), 입원기간이 17일 이하인 경우 8.90배(95% CI 2.59-30.6)(p=0.001), 동반질환에서 암의 경우에서 7.15배(95% CI 1.64-31.14)(p=0.009) 등이었다. 결론: 2015년 한국 중동호흡기증후군 유행에서 대전 클러스터의 높은 치명율은 연령(≥65세), 동반질환(특히 암), 잠복기(≤7일), 입원기간(≤17일) 등이 유의한 변수로 도출되었다.

• Journal of Preventive Medicine and Public Health
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• v.54 no.1
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• pp.31-36
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• 2021

Objectives: Non-traditional materials are used for mask construction to address personal protective equipment shortages during the coronavirus disease 2019 (COVID-19) pandemic. Reusable masks made from surgical sterilization wrap represent such an innovative approach with social media frequently referring to them as "N95 alternatives." This material was tested for particle filtration efficiency and breathability to clarify what role they might have in infection prevention and control. Methods: A heavyweight, double layer sterilization wrap was tested when new and after 2, 4, 6, and 10 autoclave sterilizing cycles and compared with an approved N95 respirator and a surgical mask via testing procedures using a sodium chloride aerosol for N95 efficiency testing similar to 42 CFR 84.181. Pressure testing to indicate breathability was also conducted. Results: The particle filtration efficiency for the sterilization wrap ranged between 58% to 66%, with similar performance when new and after sterilizing cycles. The N95 respirator and surgical mask performed at 95% and 68% respectively. Pressure drops for the sterilization wrap, N95 and surgical mask were 10.4 mmH2O, 5.9 mmH2O, and 5.1 mmH2O, respectively, well below the National Institute for Occupational Safety and Health limits of 35 mmH2O during initial inhalation and 25 mmH2O during initial exhalation. Conclusions: The sterilization wrap's particle filtration efficiency is much lower than a N95 respirator, but falls within the range of a surgical mask, with acceptable breathability. Performance testing of non-traditional mask materials is crucial to determine potential protection efficacy and for correcting misinterpretation propagated through popular media.

• Journal of Korea Water Resources Association
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• v.51 no.10
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• pp.905-916
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• 2018

The purpose of this study is to evaluate the climate change impact on watershed hydrology and flow duration in Geum River basin ($9,645.5km^2$) especially by extreme scenarios. The rainfall related extreme index, STARDEX (STAtistical and Regional dynamical Downscaling of EXtremes) was adopted to select the future extreme scenario from the 10 GCMs with RCP 8.5 scenarios by four projection periods (Historical: 1975~2005, 2020s: 2011~2040, 2050s: 2041~2070, 2080s: 2071~2100). As a result, the 5 scenarios of wet (CESM1-BGC and HadGEM2-ES), normal (MPI-ESM-MR), and dry (INM-CM4 and FGOALS-s2) were selected and applied to SWAT (Soil and Water Assessment Tool) hydrological model. The wet scenarios showed big differences comparing with the normal scenario in 2080s period. The 2080s evapotranspiration (ET) of wet scenarios varied from -3.2 to +3.1 mm, the 2080s total runoff (TR) varied from +5.5 to +128.4 mm. The dry scenarios showed big differences comparing with the normal scenario in 2020s period. The 2020s ET for dry scenarios varied from -16.8 to -13.3 mm and the TR varied from -264.0 to -132.3 mm respectively. For the flow duration change, the CFR (coefficient of flow regime, Q10/Q355) was altered from +4.2 to +10.5 for 2080s wet scenarios and from +1.7 to +2.6 for 2020s dry scenarios. As a result of the flow duration analysis according to the change of the hydrological factors of the Geum River basin applying the extreme climate change scenario, INM-CM4 showed suitable scenario to show extreme dry condition and FGOALS-s2 showed suitable scenario for the analysis of the drought condition with large flow duration variability. HadGEM2-ES was evaluated as a scenario that can be used for maximum flow analysis because the flow duration variability was small and CESM1-BGC was evaluated as a scenario that can be applied to the case of extreme flood analysis with large flow duration variability.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.1
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• pp.75-79
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• 2019

Purpose Cadmium-zinc-telluride (CZT) camera with semiconductor detector is capable of dynamic myocardial perfusion SPECT for coronary flow reserve (CFR). Image acquisition with the heart positioned within 2 cm in the center of the quality field of view (QFOV) is recommended because the CZT detector based on focused multi-pinhole collimators and is stationary gantry without rotation. The aim of this study was to investigate the optimal method for measuring position of the heart within the center of the QFOV when performing dynamic myocardial perfusion SPECT with the Discovery NM 530c camera. Materials and Methods From June to September 2018, 45 patients were subject to dynamic myocardial perfusion SPECT with D530c. For accurate heart positioning, the patient's heart was scanned with a mobile ultrasound and marked at the top of the probe where the mitral valve (MV) was visible in the parasternal long-axis view (PLAX). And, the marked point on the patient's body matched with the reference point indicated CZT detector in dynamic stress. The heart was positioned to be in the center of the QFOV in rest. The coordinates of dynamic stress and rest were compared statistically. Results The coordinates of the dynamic stress using mobile ultrasound and those taken of the rest were recorded for comparative analysis with regard to the position of the couch and analyzed. There were no statistically significant differences in the coordinates of Table in & out, Table up & down, and Detector in & out (P > 0.05). The difference in distance between the 2 groups was measured at $0.25{\pm}1.00$, $0.24{\pm}0.96$ and $0.25{\pm}0.82cm$ respectively, with no difference greater than 2 cm in all categories. Conclusion The position of the heart taken using mobile ultrasound did not differ significantly from that of the center of the QFOV. Therefore, The use of mobile ultrasound in dynamic stress will help to select the correct position of the heart, which will be effective in clinical diagnosis by minimizing the image quality improvement and the patient's exposure to radiation.

• The Korean Journal of Air & Space Law and Policy
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• v.32 no.1
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• pp.225-285
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• 2017

In regard to the regulations related to the RPA(Remotely Piloted Aircraft), which is sometimes called in other countries as UA(Unmanned Aircraft), ICAO stipulates the regulations in the 'RPAS manual (2015)' in detail based on the 'Chicago Convention' in 1944, and enacts provisions for the Rules of UAS or RPAS. Other contries stipulates them such as the Federal Airline Rules (14 CFR), Public Law (112-95) in the United States, the Air Transport Act, Air Transport Order, Air Transport Authorization Order (through revision in "Regulations to operating Rules on unmanned aerial System") based on EASA Regulation (EC) No.216/2008 in the case of unmanned aircaft under 150kg in Germany, and Civil Aviation Act (CAA 1998), Civil Aviation Act 101 (CASR Part 101) in Australia. Commonly, these laws exclude the model aircraft for leisure purpose and require pilots on the ground, not onboard aricraft, capable of controlling RPA. The laws also require that all managements necessary to operate RPA and pilots safely and efficiently under the structure of the unmanned aircraft system within the scope of the regulations. Each country classifies the RPA as an aircraft less than 25kg. Australia and Germany further break down the RPA at a lower weight. ICAO stipulates all general aviation operations, including commercial operation, in accordance with Annex 6 of the Chicago Convention, and it also applies to RPAs operations. However, passenger transportation using RPAs is excluded. If the operational scope of the RPAs includes the airspace of another country, the special permission of the relevant country shall be required 7 days before the flight date with detail flight plan submitted. In accordance with Federal Aviation Regulation 107 in the United States, a small non-leisure RPA may be operated within line-of-sight of a responsible navigator or observer during the day in the speed range up to 161 km/hr (87 knots) and to the height up to 122 m (400 ft) from surface or water. RPA must yield flight path to other aircraft, and is prohibited to load dangerous materials or to operate more than two RPAs at the same time. In Germany, the regulations on UAS except for leisure and sports provide duty to avoidance of airborne collisions and other provisions related to ground safety and individual privacy. Although commercial UAS of 5 kg or less can be freely operated without approval by relaxing the existing regulatory requirements, all the UAS regardless of the weight must be operated below an altitude of 100 meters with continuous monitoring and pilot control. Australia was the first country to regulate unmanned aircraft in 2001, and its regulations have impacts on the unmanned aircraft laws of ICAO, FAA, and EASA. In order to improve the utiliity of unmanned aircraft which is considered to be low risk, the regulation conditions were relaxed through the revision in 2016 by adding the concept "Excluded RPA". In the case of excluded RPA, it can be operated without special permission even for commercial purpose. Furthermore, disscussions on a new standard manual is being conducted for further flexibility of the current regulations.

• Food Science and Preservation
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• v.22 no.2
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• pp.290-296
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• 2015

The antioxidant and ${\alpha}$-glucosidase inhibition activities of 10 kinds of seaweeds Ecklonia cava (EC), Ecklonia stolonifera (ES), Eisenia bicyclis (EB), Capsosiphon fulvescens (CF), Sargassum fulvellum (SF), Undaria pinnatifida (UP), Sargassum thunbergii (ST), Codium fragile (CFr), Hizikia fusiformis (HF), and Enteromorpha prolifera (EP) were investigated. Among all the tested seaweed extracts, the total polyphenol and flavonoid contents of the EB extract were highest 150.81 mg/g and 77.02 mg/g, respectively. The DPPH and ABTS radical scavenging abilities of the EB ethanol extract (1 mg/mL) were 86.26% and 99.71%, respectively, and its SOD-like activity and reducing power were 21.34% and 1.710 ($OD_{700}$). The ${\alpha}$-glucosidase inhibition activities of the EC, EB, and ST were above 98% at the 0.1 mg/mL concentration. These results suggest that seaweed extracts effectively prevent the what of antioxidants and decrease the blood glucose level, and may be used to develop various functional products.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.60
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• pp.3-26
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• 2013

Seller's obligation on the Delivery of Goods and Handing over the Documents are key elements in Contracts for the International Sale of Goods. The United Nations Convention on Contracts for the International Sale of Goods(CISG) has been entered into force on 1 January 1988 to create international certainty and uniformity in the law and to govern issues that arise in an international sale of goods transaction. The Incoterms were first published by the ICC in 1936 and were most recently revised in 2010. Incoterms 2010 are entering into force on 1 January 2011. The Incoterms focus on the seller's delivery obligations and reflect the principle that the risk of loss or damage to the goods passes from the seller to the buyer when the seller has fulfilled its obligations to deliver the goods. This study highlights basic rules covering seller's obligation of delivery of goods and handing over the documents under the Incoterms 2010 and the United Nations Convention and Contracts for the International Sale of Goods. In the second chapter, this study will provide analyses and compare these two legal systems in relation to the basic rules governing delivery of goods and passing of risks in contract of sale. This chapter evaluates the meaning of Article 31 and Article 67(1) and FOB, CFR, CIF & FCA, CPT, CIP terms of Incoterms 2010. Chapter Three will focus on handing over the documents. Article 30 CISG imposes the seller's primary obligations to deliver the goods and to hand over documents relating to them. Article 34 CISG supplements the seller's obligation in relation to documents by providing that the seller must hand over documents relating to the goods. In contrast, Article 58(1) CISG imposes on the buyer the obligation to pay only when it has received the goods or documents controlling their disposition. I reviewed only some of the documents relating to the goods are documents controlling their disposition. This chapter considers the meaning of the phrase "documents that control the disposition of the goods and do not control disposition of the goods." Finally, the fourth chapter will assess the meaning of rules of CISG and Incoterms 2010.

• Journal of radiological science and technology
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• v.32 no.1
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• pp.1-15
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• 2009

Newly published IEC 60601-1-3 ; 2008 2nd Edition has two important meanings. First, Radiation Quality and Dose should make sure for safety of patient and staff in manufacturing diagnostic X-ray equipment. Second, it should be minimized of Leakage Radiation, Residual Radiation, and Stray Radiation. The requirement to make enactment or revision of national standard for diagnostic X-ray Equipment is as follows : 1. It should be adjusted the new standard to the recent IEC Publication under the consideration of the Korea medical circumstances. 2. For focus to the Radiation Safety, IEC 60601-1-3 (General requirements for radiation protection in diagnostic X-ray equipment) could be applied to the new regulation. It should be compact sentence. 3. A sudden Notification change should not be desired. It needs a enough time to make easy the circumstances.

• Journal of Radiation Protection and Research
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• v.38 no.2
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• pp.91-99
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• 2013

There are many reasons for decommissioning of cyclotron such as not only age-related deficiency, any serious wear or damage but also relocation, upgrade and changing mission. Decommission of cyclotron in USA and EU give rise to a lot of low-level radioactive waste and costs. Various research on decommissioning of particle accelerator have been carried to reduce the cost of decommissioning in USA and EU. In USA, the NRC require DFP (Decommissioning Funding Plan) to authorized licenser by 10 CFR Part 30.35. To resolve radioactive waste problem and reduce the estimated cost of cyclotron decommissioning, we should consider technical aspects (decommissioning procedures, decontamination techniques, etc.) and safety aspects(residual radioactivity, the expected dose, etc) for decommissioning. In this study, we analyzed practical information on the decommissioning of cyclotron in ANL (Argonne National Laboratory) and Belgium (EU). And we investigated the experience on the cyclotron relocation from SNUH (Seoul National University Hospital) to SKKU (Sungkyunkwan University). From these results, we provide the basic data for establishing of relevant standards on domestic cyclotron decommissioning. It is necessary to adopt the DFP for safe and economic decommissioning and waste recycling. These result could be utilized for the establishment on the standards and useful requirements.