• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.6
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• pp.906-915
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• 1986

This study reviewed the theory of acoustic emission applying generation of acoustic emission in metal cutting and proposed a relationship between fundamental cutting parameters and the root mean square (RMS) voltage of the acoustic emission on the basis of the mechanics of the orthogonal cutting operation. Experimental results are presented for 6063-T5 Auminum and the validity of this relationship is evaluated by a series of tests varying cutting speed, feed rate and rake angle in orthogonal cutting. The original formula derived theoretically has been modified in order to utilize independent of fundamental cutting parameters. RMS voltage of acoustic emission depends on cutting speed and strain rate, but it is not much affected by feed rate. Applying lubricant, the drop of RMS level has been observed.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.517-523
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• 2003

The physical properties of polypropylene (PP) membranes under the radiation field were investigated. To calculate radiation flux affecting to PP, it was used MCNP4A Code. The PP membrane and deoxygenation equipment were standardized to bar structure in order to calculate the phonton flux with MCNP4A Code. The change in the properties of the PP membrane to be used in deoxygenation equipment was rarely occurred during the usage work because the radiation level of reactor coolant water was very low level and The doses of radiation workers are very low. From the results, it was found that the Physical properties of PP membranes which used for nuclear power plant reactor coolant water disposal were not rarely changed under the simulated radiation field.

• Fire Science and Engineering
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• v.24 no.2
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• pp.178-184
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• 2010

In this study, a smoke or a heat which occurs by a fire is perceived by wireless detector, this signal is transmitted to the receiving device by the wireless installation which is not the wire device and wire/wireless integration system which sends this signal to main server via wire system is proposed. In addition wireless heat/smoke detector, wireless module, firmware and wire/wireless integration controller were developed and for verifying regarding the efficiency and applicability of wire/wireless installation actual place application experiment was really accomplished with a transmission tower, a multipurpose building, and a station etc of the subway. The experimental result, it could operate the system which is proposed normally with all experimental object ones and, future actual place application possibility could verify.

• Journal of Radiation Protection and Research
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• v.14 no.1
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• pp.66-70
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• 1989

In routine testing, the radioactive neutron sources are particularly suitable for producing standard. neutron fields. The ISO TC-85 has proposed neutron reference radiation for the calibration of neutron measuring devices used for radiation protection purposes. Radiation laboratory of KSRI has installed a standard irradiation facility using $^{252}Cf$ and $^{241}Am-Be$ sources for calibrating personal dosimeters according to the recommendations given in ISO TC-85. In this study, correction factors for calibration related to neutron scattering and anisotropy are obtained by experiments with commercial rem meter for demonstration purposes.

• Nuclear Engineering and Technology
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• v.27 no.3
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• pp.447-452
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• 1995

경·중수로 연계 핵연료 주기 (Direct Use of Spent PWR Fuel in CANDU : DUPIC ) 기술개발의 핵물질 보장조치(Safeguards)는 경수로 사용후 핵연료를 중수로에 재 활용하기 위한 DUPIC 공정에 대한 최적 보장조치 시스템을 구축하여, 국제 원자력 기구(IAEA) 및 국제 원자력 사회에서 핵 투명성확보 및 신뢰도를 향상시키는 것을 기술개발의 목적으로 하고 있다. DUPIC 공정은 고립된 차폐시설내의 고준위 방사선장 하에서 가동되므로 타 시설에 비해 핵 물질 전용 가능성은 희박하지만, 전 공정이 원격제어 되야 하고, 조업조건이 정복해야 하므로 기존의 보장조치 기술보다 더욱 발전된 계량관리시스템, 측정시스템 및 감시시스템 등을 개발하여야 한다. 이를 위해 본 연구에서는 각 항목에 대한 요소 분석 및 각 항목별 향후 연구방향에 대해 분석하였다. DUPIC 공정 전반에 대한 핵물질 계량관리를 위해 물질수지구역 (Material Balance Area : MBA) 및 주요측정 지점 (Key Measurement Point : KMP )을 설정하여 각 측정지점별 측정방법 및 재고검증(Inventory Verification) 방법을 분석하였다. 최적 측정시스템을 개발하기 위해 적용 가능한 비파괴분석 방법들을 분석한 결과, 핵분열성 물질 함량을 정량적으로 측정할 수 있는 수동적 중성자 측정법이 가장 적합하다는 결론을 얻었다. 또한, 감시시스템을 개발하기 위해 전용전략의 주요 요소 및 전용경로 등을 분석하였으며, 핵물질 및 시설에 대한 물리적 방호체제를 DUPIC시설에 적용하기 위하여 물리적 방호에 필요한 방호체제 요소를 분석하여 DUPIC 시설을 위한 가상적인 방호체제를 구축하였다.

• Nuclear Engineering and Technology
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• v.7 no.4
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• pp.277-284
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• 1975

A result of measurement for the relative dose distribution of neutron gamma mixed radiation field in the biological irradiation facility installed at TRIGA Mark-III reactor is described. The relative dose distributions of neutron-gamma mixed radiation field in the biological exposure room have been experimentally determined using a thermoluminescent dosimeter. Presented herein in graphical forms are the experimental results obtained. It as observed that the region commonly having the characteristics of rather homogeneous horizontal and lateral dose distributions is confined to the area bounded by the two planes horizontally parallel to the beam direction with heights of about 40 cm and 130 cm, respectively, at distances beyond 100 cm from the segmentary surface of the aluminum pool liner projected into the the exposure room, while other areas show a steeper gradient in dosage, especially the places adjacent to the segment of the aluminum pool liner and near the inner po${\gamma}$lion of the concrete walls of the exposure room.

• Nuclear Engineering and Technology
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• v.7 no.4
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• pp.285-293
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• 1975

A result of the study to determine the depth-dose distribution along the central axis of a polyethylene sphere in diameter of 30cm is described. Depth-dose distribution in the polyethylene sphere for broad beam of monoenergetic photons has been experimentally determined with thermoluminescent dosimeter as a cavity dosimeter. The conversion of dose absorbed in the LiF TLD to dose in the surrounding medium was carried out on the basis of Burlin's generalized cavity theory. Presented in graphical forms are the results obtained. The maximum absorbed doses in the sphere were observed at the depth of about 0.3cm and 0.5cm from the surface of the sphere for the gamma-rays of $^{137}$ Cs and $^{60}$ Co, respectively.

• Journal of Korea Ship Safrty Technology Authority
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• s.32
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• pp.46-56
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• 2012

해양사고 예방 또는 해양사고 시 2차 피해 감소를 위한 관점에서 안전수역, 안전항구 및 최적 수리장소의 제공 또는 제공되는 장소까지 안전한 수로의 안내는 해양선진국으로 갖추어야 할 핵심 해사안전 서비스의 하나로 볼 수 있다. Erika호 해양사고와 같은 중대사고로 큰 손해를 겪은 국제사회는 피난처의 중요성을 깨닫고 여러 해를 거친 검토 끝에 피난처의 제공목적, 선장과 구조자의 책임지침 등을 담은 IMO Res. A.949(23) 및 A.950(23)과 같은 피난처 관련 지침을 제정하게 되었다. 이 지침을 바탕으로 덴마크, 미국, 캐나다, 남아프리카에서는 MAS 체제, 잠재적 피난처(PPOR, Potential Places of Refuge), 국가비상계획 포함 등의 방법으로 피난처를 지정하여 활용하고 있었다. 위의 요소들을 고려할 때, 우리나라 연안을 통항하는 선박들에 대한 최적의 피난처를 지정하기 위해서 연안해역 및 항만의 자연환경, 해상 및 기상조건, 과거 해양사고통계 및 분석자료, 항적도 및 교통량 등 해상교통환경의 평가를 위한 기초자료가 수집되어야 한다.

• Journal of Yeungnam Medical Science
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• v.18 no.2
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• pp.246-252
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• 2001

We report the result of a high-dose intravenous immunoglobulin therapy in a Henoch-Schnlein purpura patient with severe abdominal pain and nephrotic syndrome who did not respond to methylprednisolone pulse therapy. Kidney biopsy showed diffuse mesangial cell proliferative glomerulonephritis with fibrocellular crescent formation in approximately 50% of glomeruli. Mesangium of all glomeruli were strong positive for IgA and C3 antibodies. High-dose intravenous immunoglobulin treatment was introduced and dramatic improvement of gastrointestinal symptom and proteinuria as well as hematuria was noted. Immunoglobulin administration should be considered in Henoch-Schnlein purpura patients with steroid-resistant intractable gastrointestinal manifestation and renal involvement.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.2
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• pp.175-184
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• 2022

This study analyzed the allocation of the skipper's attention during fishing operation in the wheelhouse of a Korean coastal composite fishing vessel by using video observation. To summarize the results, the ratio of lookout, radar and GPS monitoring, which is essential for prevention of collision at sea, was significantly lower than that of other fishing operation due to the attention concentration on the work place during hauling line. In order to reduce exposure to risk of collisions due to concentration of attention to certain tasks such as line hauling, it is necessary to develop an alert system that can notify the approach of other ships or obstruction throughout the ship using information from radar or the automatic identification system. In addition, the order of attention allocation to devices and facilities obtained in this study is expected to be used as basic data for device or facility layout based on the principle of usage frequency in designing wheelhouse for coastal composite fishing vessels in the future.