• Proceedings of the Korean Nuclear Society Conference
• /
• 1997.10a
• /
• pp.713-718
• /
• 1997

In the TMI-2 accident, approximately twenty(20) tons of molten core material drained into the lower plenum. Early advanced light water reactor (LWR) designs assumed a lower head failure and incorporated various measures for ex-vessel accident mitigation. However, one of the major findings from the TMI-2 Vessel Investigation Project was that one part of the reactor lower head wall estimated to have attained a temperature of 1100$^{\circ}C$ for about 30 minutes has seemingly experienced a comparatively rapid cooldown with no major threat to the vessel integrity. In this regard, recent empirical and analytical studies have shifted interests to such in-vessel retention designs or strategies as reactor cavity flooding, in-vessel flooding and engineered gap cooling of the vessel Accurate thermohydrodynamic and creep deformation modeling and rupture prediction are the key to the success in developing practically useful in-vessel accident/risk management strategies. As an advanced in-vessel design concept, this work presents the COrium Attack Syndrome Immunization Structures (COASIS) that are being developed as prospective in-vessel retention devices for a next-generation LWR in concert with existing ex-vessel management measures. Both the engineered gap structures in-vessel (COASISI) and ex-vessel (COASISO) are demonstrated to maintain effective heat transfer geometry during molten core debris attack when applied to the Korean Standard Nuclear Power Plant(KSNPP) reactor. The likelihood of lower head creep rupture during a severe accident is found to be significantly suppressed by the COASIS options.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.38 no.6
• /
• pp.605-611
• /
• 2010

The geostationary satellite COMS is going to be launched in 2010, and, in the series of test, there are some high-pressure tests concerning the vessel tank filled with helium gas of hundreds atmospheric pressure. In this paper, authors evaluates risk associated with accidental rupture of the test system. Two possible scenarios are considered: 1) the 310-bar helium tank ruptures at the center of the acoustic chamber, and 2) the 116-bar reduced-pressure helium tank ruptures in the test room shielded by bullet-proof glasses. Using the theory of blast wave propagation and computational simulation, the dynamics of wave reflected in a confined space is investigated for highly complex unsteady flow physics.

• Journal of Yeungnam Medical Science
• /
• v.31 no.1
• /
• pp.17-20
• /
• 2014

Iatrogenic femoral artery pseudoaneurysm is a complication in patients undergoing catheterization. The risk increased when large-bore sheaths, concomitant anticoagulation therapy, and antiplatelet therapy are used during the intervention. Ultrasound-guided thrombin injection has become the treatment of choice. Rapid expansion, rupture, infection, and mass effect resulting in distal or cutaneous ischaemia or peripheral neuropathy, as well as failure of other treatment options are all indications for surgery. We report a 48-year-old man who developed hemorrhagic shock due to femoral pseudoaneurysm rupture after coronary angiography, and successfully treated by ultrasound-guided thrombin injection.

• The Korean Journal of Food & Health Convergence
• /
• v.5 no.2
• /
• pp.1-11
• /
• 2019

The objective of this study is to assess the effect of interpregnancy interval on fetal outcome among women with term premature rupture of membrane in public hospitals, Ethiopia, 2017. Facility based follow up study was conducted in Southern Ethiopia public hospitals from February 30, 2017 to August 20, 2017. Among 150 observed mothers with interpregnancy interval of less two years, 46.67 % (95% CI: (7.170, 29.93) of them experienced adverse birth outcome, but among 173 women with interpregnancy interval of two and above years, 5.78% (95% CI: (7.170, 29.93) of them experienced adverse birth outcome. The odds of adverse birth outcome were more among women with interpregnancy interval of less than two years (AOR=17.899, 95%CI: [6.425, 49.859]. The effect of interbirth interval of less than two years on adverse birth outcome of newborn was increased by length labor of >=24 hours, induction of labour and cesarean section delivery. Interpregnancy interval of less than two years, in collaboration with other risk factors, is the main predictor of adverse birth outcome. Therefore especial attention should be given to mothers with birth spacing by using family planning methods to reduce adverse birth outcome.

• Journal of the Society of Naval Architects of Korea
• /
• v.60 no.6
• /
• pp.433-440
• /
• 2023

This study aims to establish safety zones for bunkering operations of hydrogen propulsion ships in coastal areas through risk assessment and evaluate their validity. Using a 350 kW-class ferry operating in Busan Port as the subject of analysis, with quantitative risk assessment based on accident consequence and frequency analysis, along with a social risk assessment considering population density. The results of the risk assessment indicate that all scenarios were within acceptable risk criteria and ALARP region. The most critical accident scenarios involve complete hose rupture during bunkering, resulting in jet flames (Frequency: 2.76E-06, Fatalities: 9.81) and vapor cloud explosions (Frequency: 1.33E-08, Fatalities: 14.24). For the recommended safety zone criteria in the 6% hose cross-sectional area leakage scenario, It could be appropriate criteria considering overall risk level and safety zones criteria for hydrogen vehicle refueling stations. This research contributes to establishing safety zone for bunkering operations of hydrogen propulsion ships through risk assessment and provides valuable technical guidelines.

• Journal of Korean Neurosurgical Society
• /
• v.67 no.5
• /
• pp.550-559
• /
• 2024

Objective : This study focuses on identifying potential complications following oblique lumbar interbody fusion (OLIF) through routine magnetic resonance (MR) scans. Methods : From 650 patients who underwent OLIF from April 2018 to April 2022, this study included those with MR scans taken 1-week post-operatively, and only for indirect decompression patients. The analysis evaluated postoperative MR images for hematoma, cage insertion angles, and indirect decompression efficiency. Patient demographics, post-operatively symptoms, and complications were also evaluated. Results : Out of 401 patients enrolled, most underwent 1- or 2-level OLIF. Common findings included approach site hematoma (65.3%) and contralateral psoas hematoma (19%). The caudal level OLIF was related with less orthogonality and deep insertion of cage. Incomplete indirect decompression occurred in 4.66% of cases but did not require additional surgery. Rare but symptomatic complications included remnant disc rupture (four cases, 1%) and synovial cyst rupture (four cases, 1%). Conclusion : This study has identified potential complications associated with OLIF, including approach site hematoma, contralateral psoas hematoma, cage malposition risk at caudal levels, and radiologically insufficient indirect decompression. Additionally, it highlights rare, yet symptomatic complications such as remnant disc rupture and synovial cyst rupture. These findings contribute insights into the relatively under-explored area of OLIF complications.

• Clinical and Experimental Pediatrics
• /
• v.63 no.2
• /
• pp.48-51
• /
• 2020

Background: The etiopathogenesis of late preterm (LPT) birth is undetermined. Placental histopathology, which reflects an adverse intrauterine environment and is reportedly associated with preterm labor and neonatal morbidities, has not been studied in LPT infants. Purpose: We investigated placental pathological lesion as markers of an adverse intrauterine environment during LPT labor. Methods: This retrospective case-control study compared placental histopathological and clinical variables between LPT and term neonates. Placental variables included chorioamnionitis, funisitis, hemorrhage, abruption, infarction, calcification, and syncytial knots. Maternal variables included age, substance abuse, pregnancyassociated diabetes mellitus and hypertension, duration of rupture of membrane, antibiotic use, and magnesium sulfate, whereas, those of neonates included gestational age, birth weight, race, sex, and Apgar scores. Standard statistical proedures were applied to analyze the data. Results: Chorioamnionitis (50% vs. 17.8%, P<0.001) and funisitis (20% vs. 4.4%, P=0.002) were more common in term infants. Placental infarction rate was insignificantly higher in LPT infants (25.6% vs. 14.3%, P=0.08). The mothers in the LPT group were older (30.4 years vs. 28.1 years, P=0.05; odds ratio [OR], 1.06; 95% confidence interval [CI], 0.998-1.12, P=0.056) and more often suffered from hypertension (28.9 vs. 12.9 %, P=0.02), and received magnesium sulfate (48.9 vs. 20%, P< 0.001; OR, 2.86; 95% CI, 1.12-7.29, P<0.05). Duration of rupture of membrane was higher in term infants (13.6 hours vs. 9.1 hours, P<0.001). Chorioamnionitis (OR, 0.33; 95% CI, 0.13-0.79; P<0.05) was associated with a lower risk of LPT delivery. Conclusion: Placental infection is not a risk factor for LPT births. There is a nonsignificant predominance of vascular anomalies in LPT placentas. Higher maternal age, magnesium sulfate therapy, and maternal hypertension are clinical risk factors for LPT labor.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.42 no.3
• /
• pp.162-165
• /
• 2016

We report a case of a morbidly obese man with an aortic aneurysm, in whom dental surgery was performed before elective cardiac surgery. His aortic aneurysm required emergency surgery. However, because of his morbid obesity, elective cardiac surgery was planned. Considering the high risk of infective endocarditis, dental surgery was required. Our patient was at a high risk of aortic rupture caused by hypertension and breathing difficulty in the supine position. Dexmedetomidine (DEX) is an anti-anxiety, sedative, and analgesic medicine that can stabilize circulatory dynamics and minimize blood pressure fluctuations. We administered intravenous DEX for sedation of the patient in Fowler's position. In conclusion, our understanding of the risk factors of DEX enabled us to perform safe invasive oral treatment.

• Journal of the Korean Institute of Gas
• /
• v.16 no.3
• /
• pp.22-28
• /
• 2012

For a methanol separation column of the BPA (Bisphenol A) plant, HAZOP (hazard and operability) assessment was performed and damage ranges were predicted from the accident scenarios for the fire and the explosion. As a result, the damage range of the jet fire was 20 m in the case of rupture of the discharge pipe (50 mm diameter) of safety valve, and that of the flash fire was 267 m in the case of catastrophic rupture. Also, the damage ranges of the unconfined vapor cloud explosion (UVCE) for the rupture of the discharge pipe and for the catastrophic rupture were 22 m and 542 m, respectively. For the worst case of release scenarios, safety measures were suggested as follows: the pressure instruments, which can detect abnormal rise of the internal pressure in the methanol separation column, should be installed by the 2 out of 3 voting method in the top section of the column. Through the detection, the instruments should simultaneously shut down the control and the emergency shut-off valves.

• Journal of the Korea Convergence Society
• /
• v.10 no.1
• /
• pp.339-351
• /
• 2019

This study was conducted to identify the factors associated with the ruptured intracranial aneurysm (RIA) among demographic, admission to hospital, clinical, aneurysym itself and lifestyle characteristics. Medical records of RIA patients and un-RIA patients which had been admitted to undergo treatment including surgery (From January to December 2016) were included into data analysis. Multiple logistic regression showed that two and more than warning signs (14.14 (CI: 1.25-159.40)) indicated the greatest odds ratio with RIA, was followed by headache more than 3 scores (13.95 (CI: 3.68-52.83)), the admission via emergency room (13.62 (CI: 4.85-38.26)), single marital status (9.72 (CI: 2.22-42.49)), 1 mmHg increased systolic blood pressure (1.04 (CI: 1.01-1.08)), 1 score increased GCS (0.58 (CI: 0.37-0.90)), arrythmia finding in electrocardiogram (3.70 (CI: 1.22-11.22)) and increased age (0.95 (CI: 0.91-0.99)). The risk groups having factors associated with RIA were identified. Preventive activities including routine assessment should be done before developing the rupture and urgent care should be needed after developing the rupture for risk groups.