• Title/Summary/Keyword: accident-free

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A Study on the free drop impact analysis of the impact limiter for radioactive material transportation cask (방사성물질 운반용기 완충체의 자유낙하 충격 거동에 관한 연구)

  • 박홍윤;신동필;서기석;정성환;홍성인
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2002.05a
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    • pp.98-102
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    • 2002
  • As the nuclear power plant has been operated continuously and increased gradually, transportation and storage of spent fuel are seriously considered nowadays. The transportation cask which contains radioactive material needs to be inspected about structural safety. About safety verification, description of IAEA Safety Standards states that cask must withstand hypothetical accident conditions. In this paper, 9m free drop impact analysis was performed for transportation cask and impact limiter by using the finite element methods. Furthermore, we obtained the dynamic behavior of wood to as compared with safety test results, and verified the safety of transportation cask.

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Free Vibration Analysis of the Partial Fuel Assembly Under Water Using Substructure Method (부분구조법을 이용한 부분핵연료 집합체의 수중 자유진동해석)

  • Lee, Kang-Hee;Yoon, Kyung-Ho;Song, Kee-Nam;Kim, Jae-Yong;Rhee, Hui-Nam
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.246-249
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    • 2006
  • Finite element vibration analysis of the trial 5x5 partial fuel assembly in the still water was performed using the substructure method. ANSYS software was used as a finite element modeling and modal analysis tool. The calculated natural frequencies of the partial fuel assembly were more consistent with the experimental results for the identical test model compared to the much larger solid model. This modeling technique can be utilized for the fuel assembly dynamic behavior analysis under normal operation, seismic and loss-of-coolant-accident analysis.

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Combined Free Flap in Reconstruction of Lower Extremity with Large Soft Tissue Defect (복합 유리 피판을 이용한 광범위한 연부 조직 결손 하지의 재건)

  • Hahn, Soo-Bong;Park, Hong-Jun;Kang, Ho-Jung
    • Archives of Reconstructive Microsurgery
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    • v.8 no.2
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    • pp.120-129
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    • 1999
  • There were many difficulties in the treatment of extensive, massive, and composite defect in the lower extremity until early 1980's. Recently, microscopic reconstruction of wide soft tissue defect is popularized. But, the combined flap, which requires wide coverage of lower extremity after soft tissue sarcoma excision or traffic accident, is still challenging to the orthopaedic surgeons. We experienced 12 cases of combined scapular and latissimus dorsi flap from 1983 to 1997 in the lower extremity reconstruction of soft tissue defect with satisfactory result. There were no serious donor site complications such as functional disturbance of shoulder joint.

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Dynamic Modeling of the Free Piston Stirling Pump for the Passive Safety Injection of the Next Generation Nuclear Power Plant (차세대 신형원자로의 피동형 안전 주입장치를 위한 프리피스톤 스터링 펌프의 동특성 모델)

  • Lee, Jae-Young
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1999.11a
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    • pp.149-154
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    • 1999
  • This paper describes a passive safety injection system with free piston Stirling pump working withabundant decay heat in the nuclear reactor during the hypothetical accident. The water column in the tube assembly connected from the hot chamber to the cold chamber in the pump oscillates periodically due to thermal volume changes of non-condensable gas in each chamber. The oscillating pressure in the water column is converted into the pumping power with a suction-and-bleed type valve assembly. In this paper a dynamic model describing the frequency of oscillation and pumping pressure is developed. It was found that the pumping pressure is a function of the temperature difference between the chambers. Also, the frequency oscillation depends on the length of the tube with water column.

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Detection of Aesthetic Measure from Stabilized Image and Video (정지영상과 동영상에서 미도의 추출)

  • Rhee, Yang-Won;Choi, Byeong-Seok
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.11
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    • pp.33-38
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    • 2012
  • An free-fall object is received only force of gravity. Movement that only accept gravity is free-fall movement, and a free-falling object is free falling body. In other words, free falling body is only freely falling objects under the influence of gravity, regardless of the initial state of objects movement. In this paper, we assume, ignoring the resistance of the air, and the free-fall acceleration by the height does not change within the range of the short distance in the vertical direction. Under these assumptions, we can know about time and maximum height to reach the peak point from jumping vertically upward direction, time and speed of the car return to the starting position, and time and speed when the car fall to the ground. It can be measured by jumping degree and risk of accident from car or motorcycle in telematics.

Study on the Comparison of Piezoelectric Property of Acoustic Sensor for Valve Leak Diagnosis (밸브누설 진단용 PZT 및 Pb-Free 음향센서의 압전특성 비교 연구)

  • Lee, Sang-Guk;Park, Sung-Keun
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.3383-3388
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    • 2007
  • To compare the sensor performance of AE leak diagnosis system which can measure valve leak conditions, AE activities such as RMS voltage level, AE signal trend, leak rate degree according to AE database, FFT spectrum were measured on valve of the simulated test system for power plant. AE activities were recorded and analyzed from various operating conditions including different temperature, pressure difference, valve size and fluid using both piezoelectric acoustic emission sensor and Pb-Free acoustic emission sensor. The results of this study are utilized to select the type of sensors, the frequency band for filtering and thereby to improve the signal-to-noise ratio for diagnosis or monitoring of valves in operation. As the final result of application study above, portable type leak diagnosis system by AE was developed. The outcome of the study can be definitely applied as a means of the diagnosis or monitoring system for energy saving and prevention of accident for power plant valve.

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Free Vascularized Scapular and Parascapular Combined Flap Coverage for Extensive Soft Tissue Injury of the Extremity (견갑 및 부견갑 병합 유리피판에 의한 광범위한 사지 연부 조직 결손의 수복)

  • Choi, Soo-Joong;Chang, Kee-Young;Lee, Chang-Ju
    • Archives of Reconstructive Microsurgery
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    • v.14 no.2
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    • pp.144-151
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    • 2005
  • Purpose: Disaster as traffic accident, industrial disaster, high voltage electrical bum and flame burn of extremity have a destructive effect because of the involvement of deep structure. Generally, such injury may result in decreased function or loss of limb. In this study the successful use of the combined scapular/parascapular flap as microsurgical transfer to cover extensive defect of electrical and flame bum is reported. Material and Method: Between January 2000 and June 2001, the combined scapular and parascapular flap was used for the coverage of soft tissue defect for 7 patients were admitted to our department with high voltage electrical bum and flame burn. The recipient site were the wrist joint in 2 cases, the forearm in 1 case, the ankle joint in 1 case, the foot dorsum in 1 case, the heel in 1 case. Result: Flap survival was complete in all patients. The result of flap coverage for these deep wound was successful. Conclusion: The advantages of scapular/parascapular combined flap were coverage of the large defect, easy shaping of the flap to fit the required three dimensional configuration around the joint, non hair bearing skin of uniform thickness, minimal donor site morbidity.

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A study on improvement of house space considering the indoor life characteristics and living type for disabled (장애인의 실내 생활 특성 및 주거유형을 고려한 주거 공간별 개선 방안에 관한 연구)

  • Kim, In-Soon;Lee, Kyoo-Il;An, Sung-Joon;Lee, Young-Hwan
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.17 no.4
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    • pp.39-47
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    • 2011
  • Population ageing and the disabled population is increasing. so disabled population and elderly people in the physical environment for Barrier-Free recently has been getting attention. according to a recent welfare paradigm shift of life support promoting for the housing remodeling. but basic remodeling made of simple living environment improvement and facilities installation for the type of disability customised housing remodeling. efficient housing remodeling plan for remodeling before and after through change the safety accidents occurred ratio. living environment for the improvement of housing and reconstruction for the benefit of comprehensively considering for disability subject in Indoor living type and the type of disability, housing type etc. and personalize house was remodeling for corresponding each space problem for identify obstacles and living types. as a result satisfaction changes & safety accident rate changes as follow. first, have complained that there was a in to residents environment furniture for reconstruction of the former housing remodeling needs survey. 80.2% of total for the percentage of households with high needs remodeling. second, The survey did not meet the 29 furniture as after the construction for died about recipient & up sticks & long absence. this leave out after the safety accident Corporation about 101 housing in the 88% of households did not happen. as a result, the lower the ratio of safety accidents occurring very revealed. third, grasp the meaning for indoor living type. showed that each approach(83%), front porch(90%), kitchen, living room(91%), bedroom(93%), toilet(92%) for each space remodeling satisfaction flow through customized housing remodeling.

Structural Evaluation on HIC Transport Packaging under Accident Conditions (HIC 운반용기의 사고조건에 대한 구조평가)

  • Chung Sung-Hwan;Kim Duck-Hoi;Jung Jin-Se;Yang Ke-Hyung;Lee Heung-Young
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.3 no.3
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    • pp.231-236
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    • 2005
  • HIC transport packaging to transport a high integrity container(HIC) containing dry spent resin generated from nuclear power plants is to comply with the regulatory requirements of Korea and IAEA for Type B packaging due to the high radioactivity of the content, and to maintain the structural integrity under normal and accident conditions. It must withstand 9 m free drop impact onto an unyielding surface and 1 m drop impact onto a mild steel bar in a position causing maximum damage. For the conceptual design of a cylindrical HIC transport package, three dimensional dynamic structural analysis to ensure that the integrity of the package is maintained under all credible loads for 9 m free drop and 1 m puncture conditions were carried out using ABAQUS code.

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Tendon Transfer with a Microvascular Free Flap in Ijured Foot of Children (건 이전술 및 유리피편 이식술을 이용한 소아 외상성 족부 손상의 재건)

  • Hahn, Soo-Bong;Lee, Jin-Woo;Jeong, Jae-Hun
    • Archives of Reconstructive Microsurgery
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    • v.5 no.1
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    • pp.112-120
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    • 1996
  • We peformed tendon transfer with a microvascular free flap for recovery of handicapped function and reconstruction for the skin and soft tissue loss. We review the clinical data of 11 children who underwent these operation due to injured foot by pedestrian accident from January, 1986 to June, 1994. The mean age of patients was 5.6 years old(3-8). Five cases underwent tendon transfer and microvascular free flap simultaneously. Another 6 cases underwent operations separately. The time interval between tendon trasnfer and microvascular free flap was average 5.6 months(2-15 months). The duration between initial trauma and tendon transfer was average 9.6 months(2-21 months). The anterior tibial tendon was used in 6 cases. Among these, the technique of splitting the anterior tibial tendon was used in 5 cases. The posterior tibial tendon was used in 3 cases and the extenosr digitorum longus tendon of the foot in 2 cases. Insertion sites of tendon transfer were the cuboid bone in 3 cases, the 3rd cuneiform bone in 3 cases, the 2nd cuneiform bone in 1 case, the base of 4th metatarsal bone in 1 case, and the remnant of the extensor hallucis longus in 3 cases. The duration of follow-up was average 29.9 months(12-102 months). The clinical results were analysed by Srinivian criteria. Nine cases were excellent and 2 cases were good. The postoperative complications were loosening of the tranferred tendon in 2 cases, plantar flexion contracture in 1 case, mild flat foot deformity in 1 case and hypertrophic scar in 2 cases. So we recommend the tendon transfer with a microvascular free flap in the case of injured foot of children combined with nerve injury and extensive loss of skin, soft tissue and tendon.

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