• 한국가스학회지
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• 제5권4호
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• pp.40-48
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• 2001

본 연구에서는 LPG 충전소에 대하여 Fussel-Vesely 중요도와 RDF 및 RIF 중요도를 수행하여 위험성 등급(Risk Rank)을 설정하였다 설정된 위험성 등급에서 위험성이 가장 큰 장치 및 설비에 대하여 정량적 위험성 분석을 수행하였다. LPG 충전소에 대한 중요도 분석결과 외부사고가 가장 위험하다고 확인되었으며, ekda 으로 구조물 결함과 파이프 배관의 부식의 위험등급이 높았다. 정량적 위험성 분석 결과로는 LPG 충전소 저장탱크의 완전히 파열하였을 경우에 대한 BLEVE의 경가 발생하였을 경우에 복사열에 의해 공정 설비에 손해를 입히기에 충분한 거리는 46.3m로 분석되었다.

• 한국안전학회지
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• 제33권3호
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• pp.33-38
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• 2018

Defects in piping caused by corrosion or external impact of underground piping can lead to high risk of rupture of the piping due to high pressure. Flammable gas can be immediately ignited when discharged from piping, causing a jetfire. The damage of the radiant heat not only threatens the health of the workers who work in the industry but also the health of the people living in the neighboring residential areas. It is important to prevent and prepare before an accident occurs. In this study, three types of flammable gas underground piping accident scenarios were investigated, and the ranges of influence were determined using Phast ver7.2. and finally regression models were formulated to predict the ranges using excel and Matlab.

• 대한기관식도과학회지
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• 제2권2호
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• pp.280-284
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• 1996

Carotid body tumors are uncommon tumors of the head and neck Surgery is the primary treatment for the tumor. Large carotid body tumors frequently encircle the common, internal, and exernal carotid arteries, and extensive bleeding often complicates the resection, increasing the risk of carotid artery rupture and damange to major cranial nerves. Grafting should be used in high-risk patients. We have experienced a case of carotid body tumor which encircle the common, internal and external carotid arteries, treated with ligation of external carotid artery and grafting using Gortex between common carotid artery and internal carotid artery.

• Korean Circulation Journal
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• 제53권9호
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• pp.581-593
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• 2023

In the catheterization laboratory, the measurement of physiological indexes can help identify functionally significant lesions and has become one of the standard methods to guide treatment decision-making. Plaque vulnerability refers to a coronary plaque susceptible to rupture, enabling risk prediction before coronary events, and it can be detected by defining a certain type of plaque morphology on coronary imaging modalities. Although coronary physiology and plaque vulnerability have been considered different attributes of coronary artery disease, the underlying pathophysiological basis and clinical data indicate a strong correlation between coronary hemodynamic properties and vulnerable plaque. In prediction of coronary events, emerging data have suggested independent and additional implications of a physiology-based approach to a plaque-based approach. This review covers the fundamental interplay between coronary physiology and plaque morphology during disease progression with clinical data supporting this relationship and examines the clinical relevance of physiological indexes in prediction of clinical outcomes and therapeutic decision-making along with plaque vulnerability.

• Journal of Chest Surgery
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• 제56권4호
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• pp.255-261
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• 2023

Background: The surgical threshold for bicuspid aortic valve (BAV)-related aortopathy is a matter of debate due to its uncertain etiology and prognosis. This study investigated the prognosis of unrepaired BAV aortopathy in patients undergoing surgical aortic valve replacement (SAVR). Methods: We retrospectively analyzed data from 720 patients (age, 60.8±11.5 years; 246 women) who underwent SAVR for BAV disease without aortic repair between 2005 and 2020 at Asan Medical Center. The clinical endpoints were defined as occurrences of sudden death, aortic dissection or rupture, and elective aortic repair. To estimate postoperative changes in the dimensions of the unrepaired aorta, the individual annual aortic expansion rate was calculated. Multiple linear regression models were used to evaluate the risk of aortic expansion. Results: The mean ascending aortic diameter was 39.5±4.6 mm, and 299 patients (41.5%) had a baseline ascending aorta diameter >40 mm. During 70.0±68.3 months of follow-up, the mean annual aortic expansion rate was 0.39±1.96 mm/yr, no aortic dissection or rupture was observed, and sudden deaths were reported in 12 patients (0.34% per person-year). Linear regression analysis revealed no significant correlation between the baseline ascending aortic diameter and postoperative aortic expansion (R²=0.004, β=-0.84, p=0.082). Conclusion: In selected patients undergoing SAVR for a BAV (<55 mm), the risk of adverse aortic events was very low. As this observation contradicts current practice guidelines advocating for proactive aortic replacement in dilated ascending aortas measuring >45 mm, the study results need further validation by studies involving larger populations or randomized controlled trials.

• 대한영상의학회지
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• 제83권5호
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• pp.1121-1127
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• 2022

임신 중 심부자궁내막증의 증상은 대부분 호전되는 것으로 알려져 있다. 그러나 심부자궁내막증과 관련하여 자궁동맥의 가성동맥류, 난소 또는 자궁동맥의 파열 및 탈락막화가 진행된 병변에 의한 복강내 출혈과 같은 심각한 산과적 합병증이 임신후반기에 드물게 보고되었다. 특히, 심부자궁내막증에 발생한 탈락막화가 진행될 경우 파열 및 출혈로 인한 심각한 모체/태아의 합병증이 발생할 수 있어 정확한 진단을 하고 임신 중 상태를 집중 감시하는 것이 필요하다. 그러나 이러한 경우는 매우 드물어 잘 알려져 있지 않으며, 저자들이 아는 한, 현재까지 보고된 심부자궁내막증에 의한 대량출혈은 모두 복강내출혈이 발생한 경우였다. 저자들은 임신 중 직장질부위 심부자궁내막증의 탈락막화가 진행되고 커지면서 질강내로 노출된 병변과 임신 후반기 병변에서 자연히 발생한 대량 질출혈의 증례를 보고하고자 한다.

• Journal of Korean Neurosurgical Society
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• 제29권8호
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• pp.1113-1120
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• 2000

Objectives : Despite advance in the surgical treatment of the intracranial aneurysm, we have to be surgical complication. The aim of this report is to evaluate the complication and its management in intracranial aneurysm operation. Methods : We reviewed our exprience with interesting cases of surgical complication of intracranial aneurysm : 1) rebleeding, 2) intra-operative premature rupture, 3) missed aneurysm in angiography, 4) vasospasm. Results : The risk of rebleeding was not related to the patients' initial comdition, but all other intracranial complications occurred significantly more often in patients graded poor compared with patients in good clinical condition. Rebleeding before early surgery remains as major cause of unfavorable outcome. The causes of intraoperative premature ruptures were as follows : 1) dural opening and arachnoid opening(8.3%), 2) hematoma removal(12.5%), 3) brain retraction(16.7%) 4) aneurysm dissection(62.5%). The double suction technique and primary hemostasis using a small piece of cotton or temporary clip resulted in good outcome even in cases with premature rupture. The incidence of missed aneurysm in angiography occurred in 10%. The causes were as thrombosed aneurysm, vasospasm on feeder artery. The most common missed aneurysm is also the most common aneurysm(anterior communicating artery aneurysm). The repeated angiography were documented in missed aneurysm. Balloon angioplasty is superior topapaverine for treatment of proximal vessel vasospasm by viture of a more sustained effect on the vessel. Papaverine can be useful as an adjunct to ballon angioplasty and also for the treatment of distal vessels that are not accessible for ballon angioplasty. Conclusion : The minimization of the complications and active treatment can reduced the mortality and morbidity of ruptured aneurysm patients.

• Journal of Cerebrovascular and Endovascular Neurosurgery
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• 제25권2호
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• pp.182-188
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• 2023

Objective: To report our experience with intraprocedural rupture (IPR) of intracranial aneurysms during endovascular treatment and evaluate alterations in vital signs as independent prognostic factors to predict the outcomes of IPR. Methods: Between January 2008 and August 2021, 34 patients (8 ruptured and 26 unruptured) were confirmed to have IPR based on our dataset with 3178 endovascular coiling procedures. The patients who underwent additional surgeries related to IPR were classified as the OP group (n=9), while those who did not receive additional surgeries were classified as the non-OP group (n=25). Vital signs were recorded during the procedure by anesthesiologists and analyzed. Results: Of the 34 patients included in this study, eight initially presented with subarachnoid hemorrhage due to a ruptured aneurysm. The clinical outcomes at discharge were significantly different between the two groups (p=0.046). In the OP group, five patients showed favorable outcomes at discharge, while four showed unfavorable outcomes. In the non-OP group, 23 patients showed favorable outcomes at discharge while two patients showed unfavorable outcomes. Maximal (MAX) systolic blood pressure (SBP) (odds ratio [OR] 1.520, 95% confidence interval [CI] 1.084-2.110; p=0.037) and higher differential value MAX-median blood pressure (MBP) (OR 1.322, 95% CI 1.029-1.607; p=0.044) remained independent risk factors for poor prognosis after IPR on multivariate logistic regression analysis. Conclusions: The MAX SBP and the difference between the maximal and baseline values of MBP are key factors in predicting the prognosis of patients after IPR, as well as providing useful information for predicting the outcome. Further research is required to confirm the relationship between naive pressure and prognosis.

• Journal of Chest Surgery
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• 제42권1호
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• pp.111-114
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• 2009

대-장골동맥류는 드문 질환으로 자연 경과 또한 잘 알려져 있지 않다. 파열의 위험성이 높고 파열시 사망률이 매우 높은 질환으로 알려져 있다. 저자들은 파열의 가능성이 높았던 대-장골 동맥류 환자에게 stent-graft를 이용한 혈관내 치료와 골반 허혈을 방지하기 위해 시행한 양측 내, 외 장골동맥간 우회술의 복합(hybrid) 치료를 시행하였기에 보고 하는 바이다

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.349-359
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• 2017

During the past 25 years, in the context of probabilistic safety assessment, efforts have been directed towards establishment of comprehensive pipe failure event databases as a foundation for exploratory research to better understand how to effectively organize a piping reliability analysis task. The focused pipe failure database development efforts have progressed well with the development of piping reliability analysis frameworks that utilize the full body of service experience data, fracture mechanics analysis insights, expert elicitation results that are rolled into an integrated and risk-informed approach to the estimation of piping reliability parameters with full recognition of the embedded uncertainties. The discussion in this paper builds on a major collection of operating experience data (more than 11,000 pipe failure records) and the associated lessons learned from data analysis and data applications spanning three decades. The piping reliability analysis lessons learned have been obtained from the derivation of pipe leak and rupture frequencies for corrosion resistant piping in a raw water environment, loss-of-coolant-accident frequencies given degradation mitigation, high-energy pipe break analysis, moderate-energy pipe break analysis, and numerous plant-specific applications of a statistical piping reliability model framework. Conclusions are presented regarding the feasibility of determining and incorporating aging effects into probabilistic safety assessment models.