• Journal of the Korean Institute of Gas
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• v.9 no.2 s.27
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• pp.8-15
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• 2005

With the introduction of 40 hour working week system, more households enjoy picnics on weekends. More gas accidents take place on Saturdays and on Sundays than any other days of week. As of October, 2004 casualties resulted from butane can accidents increased 1.5 times compared to the same period of the previous year. In this study, the influence of explosion over-pressure caused by the rupture of butane can thrown away after use was calculated by using the Hopkinson's Scaling Law and the accident damage was estimated by applying the influence on the adjacent structures and people into the Probit model. As a result of the damage estimation conducted by using the Probit model, both the damage possibility of explosion over-pressure to structures 50 meters away and that of over-pressure to people 10 meters away showed nothing. The explosion efficiency used was 100 percent. As a result of this, the actual damage influenced by the rupture of butane can would be lower than the value calculated in this study and expected to be safer.

• Journal of the Korean Institute of Gas
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• v.23 no.5
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• pp.1-7
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• 2019

Although the rupture pressure is evaluated from remaining strength when a flaw is defected to cylinder surface, but the rupture pressure can be not easy to estimate for the composite cylinders. In this study, the area capacity method is developed for the type-3 cylinders that is based on the result applied area capacity method of type-1 cylinders. And the reliability is validated by bursting test with artificial flaw at the cylinder surface. The predicted data of area capacity method and experimental results have very similar tendency. This method and results will be a very important records in field of rupture pressure estimations.

• Journal of Korean Neurosurgical Society
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• v.45 no.4
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• pp.240-242
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• 2009

Oculomotor nerve palsy (ONP) with subarachnoid hemorrhage (SAH) occurs usually when oculomotor nerve is compressed by growing or budding of posterior communicating artery (PcoA) aneurysm. Midbrain injury, increased intracranial pressure (lCP), or uncal herniation may also cause it. We report herein a rare case of ONP associated with SAH which was caused by middle cerebral artery (MCA) bifurcation aneurysm rupture. A 58-year-old woman with clear consciousness suffered from headache and sudden onset of unilateral ONP. Computed tomography showed SAH caused by the rupture of MCA aneurysm. The unilateral ONP was not associated with midbrain injury, increased ICP, or uncal herniation. The patient was treated with coil embolization, and the signs of oculomotor nerve palsy completely resolved after a few days. We suggest that bloody jet flow from the rupture of distant aneurysm other than PcoA aneurysm may also be considered as a cause of sudden unilateral ONP in patients with SAH.

• Journal of Chest Surgery
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• v.40 no.4 s.273
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• pp.309-312
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• 2007

Cervical tracheal rupture is one of the rare injuries after blunt chest trauma, and this can be explained by several mechanisms. Early diagnosis and treatment of tracheal rupture after trauma can reduce the mortality and morbidity. We report here on a surgical experienced case of complete rupture of the cervical tracheal that was due to increased intra-tracheal pressure after a compression injury to the chest of an 8 years old child. We also include a review of the literature.

• Journal of the Korean Society of Safety
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• v.1 no.1
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• pp.41-49
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• 1986

Modern technological progress demands the use of materials at high temperature and high pressure. One of the most critical factors in considering such applications-perhaps the most critical one-is creep behavior. In this study the activation energy for the creep rupture (Qf) and the stress dependence of rupture time (n') have been determined during creep of Al 7075 alloy eve, the temporature range of $200^{\circ}C to 500^{\circ}C$ and stress range of 0.64 kgf/$\textrm{mm}^2$ to 9.55 kgf/$\textrm{mm}^2$, respectively, in order to investigate the creep-rupture property. Constant load creep tests were carried out in the enperiment At around the temperature $210^{\circ}C~390^{\circ}C$ and the stress level 1.53~9.55(kgf/$\textrm{mm}^2$), the stress dependence of rupture time(n') had the value of 6.6~6.78 but at 50$0^{\circ}C$, the value of 1.3. Besides at around the temperature of $200^{\circ}C~500^{\circ}C$ and under the stress level of 0.89~8.51 (kgf/$\textrm{mm}^2$), the activation energy for the creepprupture (Qf) was nearly equal to that of the volume self diffusion of pure aluminum (34Kca1/mo1e)

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.101-104
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• 2010

A bulkhead-type pulse separation device has been developed for the multi-pulse rocket motor. The design parameters of the pulse separation device were the shape of the rupture disc slit, welding conditions, and the implementation of the seal disc. The pneumatic tests of the fabricated pulse separation devices showed that the rupture pressure increased as the quantity of the rupture disc slit and welding strength increased and the seal disc was implemented.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.213-218
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• 2012

Survey on the hypergolic igniter and rupture disc for liquid rocket engines was performed. The patent of the igniter for US MC-1 and Russia RD-170 Engine and the disc for NASA's space vehicle were analyzed. The types, characteristics, performances, design parameters and ASME standards of the disc are examined. The performances have manufacturing tolerance, reverse pressure, flow disturbance, fragmentation, material, working fluid and operating ratio. Also, survey on structural analyses of the rupture disc were performed.

• Archives of Plastic Surgery
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• v.33 no.1
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• pp.120-123
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• 2006

Spontaneous extensor pollicis longus tendon rupture is commonly caused by attrition of the tendon from trauma or inflammatory processes. We experienced a patient with extensor pollicis longus tendon rupture after steroid injection, in which the rupture may have been caused by the effects of steroid itself as well as direct damage from the needle. A 51-year-old woman complained of inability to extend her right thumb at the first metacarpophalangal & interphalangeal joint level. The patient had a history of local steroid injection into the dorsal & radial side of wrist on two occations, and had no history of trauma or rheumatologic disease. After a physical examination of the patient, we decided to explore the wrist. The patient agreed with operation. Intraoperatively, an incision was made into the wrist and the proximal and distal ends of the ruptured extensor pollicis longus tendon were identified. The defect between the proximal and the distal end was measured to approach 8cm, and a palmaris longus tendon graft was performed. After three months of rehabilitation, the first metacarpophalangal & interphalangeal joint recovered the normal range of motion. Steroid injection has been widely used in various musculoskeletal disorders such as rheumatoid arthritis and osteoarthritis. However, inadvertent steroid injection into the extra or intra articular spaces may lead to tendon rupture. Steroids reduce tensile strength by decreasing tenocyte activity and collagen synthesis. Also, the physical effect of direct needle-stick injury into the mesotenon and blood vessels around the tendon may cause damage. In addition, hematoma and edema may increase pressure around the tendon and compromise blood supply, leading to tendon degeneration and subsequent rupture. When injecting steroid into an articular area, all physicians should have a complete understanding of the surrounding anatomy and always keep in mind the hazards of such procedures.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.2
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• pp.64-70
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• 2019

In recent years, attention has been paid to the integrity of steam generator (SG) tubes due to severe accident and beyond design basis accident conditions. In these transient conditions, steam generator tubes may be damaged by high temperature and pressure, which might result in a risk of fission products being released to the environment due to the failure. Alloy 690 which has increased the Cr content has been replaced for the SG tube due to its high corrosion resistance against stress corrosion cracking (SCC). However, there is lack of research on the high temperature creep rupture and life prediction model of Alloy 690. In this study, creep test was performed to estimate the high temperature creep rupture life of Alloy 690 using tube specimens. Based on manufacturer's creep data and creep test results performed in this study, creep life prediction was carried out using the Larson-Miller (LM) Parameter, Orr-Sherby-Dorn (OSD) parameter, Manson-Haford (MH) parameter, and Wilshire's approach. And a hyperbolic sine (sinh) function to determine master curves in LM, OSD and MH parameter methods was used for improving the creep life estimation of Alloy 690 material.

• Journal of Welding and Joining
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• v.15 no.1
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• pp.92-100
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• 1997

Weld repair of ASTM A-470 class 8 high pressure (HP) steam turbine rotor steel has been performed to extend the service life of older fossil units. Microhardness measurements were conducted across the weldment from unaffected base metal (BM) to weld metal (WM). The hardness of the BM was VHN 253, however it dropped up to VHN 227 at the heat affected zone (HAZ) close to unaffected BM for multipass SAW. This area of hardness drop is called "siftening zone" and has a width of 0.5-0.6mm. During creep rupture test, failure occurred around the softening zone and rupture time was 772.4hr at 19Ksi (132 Mpa) and 593.deg. C. Multipass MIG and TIG welding have been employed to reduce the softening zone width. The softening zone width for MIG was 0.3-0.4mm and for TIG was zero-0.4mm depending on heat inputs. However creep rupture time was decreased as softening zone width reduced. Creep rupture time also showed a close relationship with heat inputs in TIG process. The higher heat input, the longer rupture time. Most failure occurred at intercritical HAZ (ICHAZ), however rupture location was shifted to coarse grained HAZ (CGHAZ) as heat input decreased. The rupture surface showed tearing and dimple which indicated transgranular fracture. fracture.