• Journal of Chest Surgery
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• 제3권1호
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• pp.47-54
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• 1970

This is a report on two cases of aortic prostheses using Nylon tube. (Edwards-Tapp A-G Tube, Chemically treated braided Nylon arterial grafts). Especially, the complications after infection of synthetic graft are discussed with reviewing literature. First case was the patient who came to our hospital with rupture of the right femoral artery at the femoral fossa due to pyogenic necrotic process. After femoral arterial prostheses, good pulsation of dorsal artery of foot was obtained. However, the tube was obstructed after 8 weeks postoperatively due tll the complication of infection. In spite of the tube was removed because of obstruction and foreign body reaction of synthetic graft, an amputation of the leg was not necessary for formation of good collateral circulation. Second case was a case of aortic aneurysmal rupture in thoraco-abdominal junction which developed by the trauma of rib resection for osteomyelitis of the left 12th. rib An implantation of aortic graft was performed at the lowest tho13cic aorta by the way of thoraco-abdominal bypass without arterial pump. However, infection produced pyothorax in the left pleural cavity, exposing the tube within the pyothorax. The rupture of the anastomosed upper line occurred in 8 weeks postoperatively and the patient expired.

• Nuclear Engineering and Technology
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• 제35권3호
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• pp.179-190
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• 2003

The multiple steam generator tube rupture (SGTR) event scenario with available safety systems was experimentally and analytically evaluated. The experiment was conducted on the large scaled test facility to simulate the multiple SGTR event and investigate the effectiveness of operator actions. As a result, it indicated that the opening of pressurizer power operated relief valve was significantly effective in quickly terminating the primary-to-secondary break flow even for the 6.5 tubes rupture. In the analysis, the recent version of RELAP5 code was assessed with the test data. It indicated that the calculations agreed well with the measured data and that the plant responses such as the water level and relief valve cycling in the damaged steam generator were reasonably predicted. Finally, sensitivity study on the number of ruptured tubes up to 10 tubes was performed to investigate the coolant release into atmosphere. It indicated that the integrated steam mass released was not significantly varied with the number of ruptured tubes although the damaged steam generator was overfilled for more than 3 tubes rupture. These findings are expected to provide useful information in understanding and evaluating the plant ability to mitigate the consequence of multiple SGTR event.

• Nuclear Engineering and Technology
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• 제50권6호
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• pp.981-988
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• 2018

An experiment was performed for the OECD/NEA ROSA-2 Project with the large-scale test facility (LSTF), which simulated a steam generator tube rupture (SGTR) accident due to a double-ended guillotine break of one of steam generator (SG) U-tubes with operator recovery actions in a pressurized water reactor. The relief valve of broken SG opened three times after the start of intact SG secondary-side depressurization as the recovery action. Multi-dimensional phenomena specific to the SGTR accident appeared such as significant thermal stratification in a cold leg in broken loop especially during the operation of high-pressure injection (HPI) system. The RELAP5/MOD3.3 code overpredicted the broken SG secondary-side pressure after the start of the intact SG secondary-side depressurization, and failed to calculate the cold leg fluid temperature in broken loop. The combination of the number of the ruptured SG tubes and the HPI system operation difference was found to significantly affect the primary and SG secondary-side pressures through sensitivity analyses with the RELAP5 code.

• Journal of Dental Anesthesia and Pain Medicine
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• 제21권2호
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• pp.167-171
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• 2021

We describe the successful insertion of a nasotracheal tube following repeated cuff rupture. The patient was a 55-year-old woman with a history of nasal trauma and multiple rhinoplasties, who underwent elective Lefort I osteotomy and bilateral sagittal split osteotomy for correction of skeletal facial deformity. During fiberoptic bronchoscope-guided nasal intubation after the induction of general anesthesia, the tracheal tube repeatedly ruptured in both nares, despite extensive preparation of the nasal airways. We covered the cuff with a one-inch tape, intubated to the level of the oropharynx, pulled the tracheal tube out through the mouth, and removed the tape. The tracheal tube was then backed out to the level of the uvula, and was successfully advanced.

• Journal of Chest Surgery
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• 제32권8호
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• pp.765-767
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• 1999

기관 삽관으로 인한 기관 기관지 파열은 매우 드문 합병증이다. 저자들은 이중관 튜브의 삽관후 발생한 기관 파열을 경험하였다. 76세 여자 환자가 간헐적인 기침과 흉부 불편감을 주소로 내원하였다. 재발된 선천성 좌측주 기관지 식도 루 진단하에 수술을 시행하였다. 수술중 우연히 기관파열이 관찰되었고 기관파\ulcorner은 풍선의 과팽창에 의한 것이었으며 파열부위의 기관을 prolene과 흡수성 봉합사를 이용하여 단단 문합 하였다. 수술후 환자는 합병 증없이 퇴원하였으며 외래를 통해 추적 관찰 중이다.

• Nuclear Engineering and Technology
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• 제34권4호
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• pp.358-369
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• 2002

Abundant information about analyses of single steam generator tube rupture (SGTR) events is available because of its importance in terms of safety. However, there are few literatures available on analyses of multiple steam generator tube rupture (MSGTR) events. In addition, knowledge of transients and consequences following a MSGTR event are very limited as there has been no occurrence of MSGTR event in the commercial operation of nuclear reactors. In this study, a postulated MSGTR event in an APR1400 is analyzed using thermal-hydraulic system code MARSI.4. The present study aims to examine the effects of affected steam generator selection. The main steam safety valve (MSSV) lift time for four cases are compared in order to examine how long operator response time is allowed depending on which steam generate. (S/G) is affected. The comparison shows that the cases where two steam generators are simultaneously affected allow longer time for operator action compared with the cases where a single steam generator is affected. Furthermore, the tube ruptures in the steam generator where a pressurizer is connected leads to the shortest operator response time.

• 방사성폐기물학회지
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• 제20권2호
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• pp.161-170
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• 2022

The effect of oxidation time on the characteristics and mechanical properties of spent nuclear fuel cladding was investigated using Raman spectroscopy, tube rupture test, and tensile test. As oxidation time increased, the Raman peak associated with the tetragonal zirconium oxide phase diminished and merged with the Raman peak associated with the monoclinic zirconium oxide phase near 333 cm^-1. Additionally, the other tetragonal zirconium oxide phase peak at 380 cm^-1 decreased after 100 d of oxidation, whereas the zirconium monoclinic oxide peak became the dominant peak. The oxidation time had no effect on the tube rupture pressure of the oxidized zirconium alloy tube. However, the yield and tensile stresses of the oxidized nuclear fuel cladding tube decreased after 100 d of oxidation. The results of the scanning electron microscopy and transmission electron microscopy were represented with the in-situ Raman analysis result for the oxide characteristics generated on the cladding of spent nuclear fuel.

• Corrosion Science and Technology
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• 제6권3호
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• pp.112-119
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• 2007

This paper presents the importance of corrosion control and protection technology with a real case study of heater tube rupture damaged by High temperature H2S-H2 corrosion in the refinery. The heater was operated at the Hydrocracking unit and the operation temperature and pressure was $340^{\circ}C$ and $18kg/cm^{3}$ respectively. Top side of the convection tube was thinned by high temperature hydrogen sulfide and hydrogen gas as a uniform corrosion and finally ruptured under operation pressure. Damaged area (Convection tube zone) was blocked by protection wall, so it was impossible to inspect with conventional nondestructive examination. Instead the elbow area which is out of the protection wall was inspected regularly to evaluate the corrosion rate of convection tube indirectly. However the operation temperature and the phase of the process stream was different between inside the chamber and outside the chamber. As a result, it caused severe corrosion to the horizontal convection tube inside the chamber comparing to the elbow outside the chamber. Finally convection tube was corroded more rapidly than the elbow and ruptured after 13 years operation. Because of the rupture, the heater was totally burned and the operation was stopped for 3 months until it has been reconstructed. To prevent this kind of corrosion problem and accident, corrosion control should be strengthened and protection technology should be improved.

• 대한기계학회논문집
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• 제13권2호
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• pp.236-242
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• 1989

본 연구에서는 주로 보일러의 과열기 및 재열기등의 관재료로 널리 사용되고 있는 304 스테인레스강에 대하여 실제 고온부식현상을 재현한 부식환경하인 630.deg. C, 690.deg. C 및 750.deg. C 3가지 온도범위에서 크리프시험을 실시하고 고온부식이 크리프파단 특성에 미치는 영향을 부식조건이 없는 고온대기중의 실험결과와 비교 검토하였다.

• Nuclear Engineering and Technology
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• 제52권9호
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• pp.2047-2053
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• 2020

Single-tube burst tests on hydrogenated Zircaloy-4 nuclear fuel cladding under simulated loss-of-coolant accident are conducted to evaluate the impact of hydrogen on burst parameters. The heating rate and initial pressure are varied from 5 K/s to 150 K/s and 5 bar-80 bar, respectively. The hydrogen concentration in the cladding is in the range of 0-2000 wppm. Burst stress is lower for hydrogenated cladding in α-phase. A significant loss of ductility is observed in α-phase and lower α + β-phase for hydrogenated cladding. However, the burst strain is higher for hydrogenated cladding in β-phase. There is a sigmoidal dependency of rupture area with initial stress and rupture area is larger for hydrogenated cladding. A novel burst stress correlation for hydrogenated Zircaloy-4 cladding has been proposed.