• Korean Journal of Radiology
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• 제22권11호
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• pp.1749-1763
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• 2021

Coronary computed tomography angiography (CCTA) is routinely used for anatomical assessment of coronary artery disease (CAD). However, invasive measurement of fractional flow reserve (FFR) is the current gold standard for the diagnosis of hemodynamically significant CAD. CT-derived FFRCT and CT perfusion are two emerging techniques that can provide a functional assessment of CAD for risk stratification and clinical decision making. Several clinical studies have shown that the diagnostic performance of concomitant CCTA and functional CT assessment for detecting hemodynamically significant CAD is at least non-inferior to that of other routinely used imaging modalities. This article aims to review the current clinical evidence and recent developments in functional CT techniques.

• Clinical and Experimental Reproductive Medicine
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• 제47권1호
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• pp.1-11
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• 2020

Endometriosis is a common inflammatory disease in women of reproductive age and is one of the major causes of infertility. Endometriosis causes a sustained reduction of ovarian reserve through both physical mechanisms and inflammatory reactions, which result in the production of reactive oxygen species and tissue fibrosis. The severity of endometriosis is related to ovarian reserve. With regard to infertility treatment, medical therapy as a neoadjuvant or adjuvant to surgical therapy has no definite beneficial effect. Surgical treatment of endometriosis can lead to ovarian injury during the resection of endometriotic tissue, which leads to the deterioration of ovarian reserve. To overcome this disadvantage, a multistep technique has been proposed to minimize the reduction of ovarian reserve. When considering surgical treatment of endometriosis in patients experiencing infertility, it should be kept in mind that ovarian reserve can be reduced both due to endometriosis itself and by the process of removing endometriosis. In cases of mild- to moderate-stage endometriosis, intrauterine insemination with ovarian stimulation after surgical treatment may increase the likelihood of pregnancy. In cases of severe endometriosis, the characteristics of the patient should be considered in a multidisciplinary manner to determine the prioritization of treatment modalities, including surgical treatment and assisted reproduction methods such as in vitro fertilization. The risk of cancer, complications after pregnancy, and infection during oocyte retrieval should also be considered when making treatment decisions.

• 한국안전학회지
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• 제14권4호
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• pp.120-125
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• 1999

This study evaluated the effect of the accidents caused by fire, explosion, and toxic gas release by using SuperChems, quantitative hazardous material release modeling software, which estimates the potential area of damage. According to the loss severity, the appropriate risk management principles can be applied. Risk management is divided into the two methods which are risk control and risk financing. Risk control includes risk avoidance, risk spreading and diversification, and risk reduction. Risk financing includes risk retention and risk transfer. The results of this study can help the related company determine the appropriate reserve fund and the amount to be insured against the third party losses according to the estimated loss severity.

• 한국건설관리학회논문집
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• 제23권5호
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• pp.98-107
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• 2022

본 연구의 목적은 플랜트 건설사업에서 모듈러 설계대안에 대한 위험기반의 평가지수를 도출하는 모델을 제안하는 것이다. 이에 따라 ① 기초사업비와 모듈을 적용하는 대상과 범위를 설정하는 단계, ② 설계, 구매, 제작, 운송, 시공업무에 대한 중요도, 편리성, 효율성 지수를 평가하는 단계, ③ 중요 위험사건의 영향에 따른 경제적 손실을 예방하기 위해서 필요한 예비비를 분석하여 총사업비를 추정하는 단계, ④ 모듈 설계대안별로 평가된 관리업무의 효율성 지수와 총사업비를 비교하여 RVI를 도출하는 단계로 구성하였다. 그리고 모델의 사용성을 검증하기 위해서 Module Plan-A는 Pipe Rack을 모듈로 적용하는 경우, Module Plan-B는 Steel Structure, Pipe Rack, Process Module을 모듈로 적용하는 경우로 설정하여 관리업무의 중요도, 편리성, 효율성 지수를 평가하고 위험예비비를 포함하여 총사업비를 추정하였다. 이와 같은 과정으로 모델을 검증한 결과, 1개의 공종에 모듈을 적용한 Module Plan-A 보다 3개의 공종에 모듈을 적용한 Module Plan-B가 관리업무의 효율성은 낮은 것으로 나타났지만, 기초사업비에서 간접비가 절감되어 종합적인 RVI는 높게 평가되었다.

• 한국시뮬레이션학회논문지
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• 제28권3호
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• pp.57-63
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• 2019

본 연구는 중소기업퇴직연금제도가 가입자들에게 보증이율(최소수익률)을 제공할 경우 사전에 적립해야 하는 보증준비금 수준을 산출하여 제시하였다. 보증준비금을 산출하기 위한 방법론으로 본 연구는 변액연금보험의 보증준비금 산출 방법론을 적용하였다. 보증준비금 산출을 위해 2010년부터 2018년까지의 3대 연기금의 자산운용 평균 수익률을 기금형 제도의 목표수익률로 설정하였으며, 보증이율은 0%, 1.0%, 1.5%, 2.0%를 각각 적용하여 시나리오 별로 요구되는 보증준비금을 산출하였다. 주요 결과로 첫째, 제도 도입기간이 길어질수록 초기 설정한 보증이율에 따른 보증준비금 간의 차이는 증가하는 것으로 나타났다. 둘째, 제도가 성숙함에 따라 적립금이 부족할 가능성은 체감하였다. 결론적으로 보증이율투자전략에 내제된 수익-위험의 관계는 장기적으로 보수적 균형을 이루어야 함을 의미한다.

• Journal of Neurogastroenterology and Motility
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• 제24권4호
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• pp.559-569
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• 2018

Background/Aims Gastroesophageal reflux disease (GERD) is a common disease globally with increasing prevalence and consequently greater burden on the Healthcare system. Traditionally, GERD has been considered a disease of middle-aged and older people. Since risk factors for GERD affect a growing number of the adult population, concerns have been raised that increasingly younger people may develop GERD. We aim to determine if the proportion of younger patients has increased among the GERD population. Methods The incidence of GERD as well as several variables were evaluated during an 11-year period. Explorys was used to evaluate datasets at a "Universal" and Healthcare system in northern Ohio to determine if trends at a local level reflected those at a universal level. GERD patients were classified into 7 age groups (15-19, 20-29, 30-39, 40-49, 50-59, 60-69, and ${\geq}70$ years). Results The proportion of patients with GERD increased in all age groups, except for those who were ${\geq}70$ years in the universal dataset (P < 0.001) and those who were ${\geq}60$ years in the Healthcare system (P < 0.001). The greatest rise was seen in 30-39 years in both datasets (P < 0.001). Similarly, the proportion of GERD patients who were using proton pump inhibitors increased in all age groups except for those who were ${\geq}70$ years in both datasets (P < 0.001), with the greatest increase being the group 30-39 years (P < 0.001). Conclusion Over the last decade, there has been a significant increase in the proportion of younger patients with GERD, especially those within the age range of 30-39 years.

• Journal of Chest Surgery
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• 제55권6호
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• pp.442-451
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• 2022

Background: This meta-analysis was conducted to evaluate the effect of fractional flow reserve (FFR) on clinical outcomes after coronary artery bypass grafting (CABG). Methods: Five online databases were searched for studies that (1) enrolled patients who underwent isolated CABG or CABG with aortic valve replacement and (2) demonstrated the effect of an FFR-guided strategy on major adverse cardiac events (MACE) after surgery based on a randomized controlled trial or adjusted analysis. MACE included cardiac death, acute myocardial infarction (MI), and repeated revascularization. The primary outcomes were all MACE outcomes and a composite of all-cause death and MI, and the secondary outcomes were the individual MACE outcomes. Publication bias was assessed using a funnel plot and the Egger test. Results: Six articles (3 randomized and 3 non-randomized studies: n=1,027) were selected. MACE data were extracted from 4 studies. The pooled analyses showed that the risk of MACE was not significantly different between patients who underwent FFR-guided CABG and those who underwent angiography-guided CABG (hazard ratio [HR], 0.80; 95% CI, 0.57-1.12). However, the risk of the composite of death or MI was significantly lower in patients undergoing FFR-guided CABG (HR, 0.62; 95% CI, 0.41-0.94). The individual MACE outcomes were not significantly different between FFR-guided and angiography-guided CABG. Conclusion: FFR-guided CABG might be beneficial in terms of the composite outcome of death or MI compared with angiography-guided CABG although data are limited.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.204-204
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• 2016

Thailand had set the National Water Management Strategy which covered main six areas in the next 12 years, i.e., by priority: (1) water for household, (2) water for agricultural and industrial production, (3) water for flood and drought management, (4) water for quality issue, (5) water from forest conservation and soil erosion protection, (6) water resources management. However due to the climate change impact, there is a question for all strategies is whether to complete this mission under future climate change. If the impact affects our target, we have to clarify how to mitigate or to adapt with it. Vulnerability assessment was conducted under the framework of ADB's (with the parameters of exposure, sensitivity and adaptive capacity) and the assessments were classified into groups due to their different characteristic and the framework of the National Water Management Strategy, i.e., water supply (rural and urban), water for development (agriculture and others), water disasters (floods (flash, overflow), drought, water quality). The assessments identified the parameters concerned and weight factors used for each groups via expert group discussions and by using GIS mapping technology, the vulnerability maps were produced. The maps were verified with present water situation data (floods, drought, water quality). From the analysis result of this water resources management strategy, we found that 30% of all projects face the big impacts, 40% with low impact, and 30% for no impact. It is clear that water-related agencies have to carefully take care approximately 70% of future projects to meet water resources management strategy. It is recommended that additional issues should be addressed to mitigate the impact from climate risk on water resource management of the country, i.e., water resources management under new risk based on development scenarios, relationship with area-based problems, priority definition by viewpoints of risk, vulnerability (impact and occurrence probability in past and future), water management system in emergency case and water reserve system, use of information, knowledge and technology in management, network cooperation and exchange of experiences, knowledge, technique for sustainable development with mitigation and adaptation, education and communication systems in risk, new impact, and emergency-reserve system. These issues will be described and discussed.

• International Journal of Reliability and Applications
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• 제4권1호
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• pp.13-26
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• 2003

This paper presents a comparative study of a few commonly used maintenance scheduling methods for small utilities that consists solely of thermal generating plants. Two deterministic methods and a stochastic method are examined. The deterministic methods employ the leveling of reserve capacity criterion, of which one uses a heuristic rule to level the deterministic equivalent load obtained by using the product of the unit capacity and its corresponding forced outage rate. The stochastic method simulates the leveling of risk criterion by using the peak load carry capacity of available units. The results indicate that for the size and type of the maintenance scheduling problem described In this study, the stochastic method does not produce a schedule which is significantly better than the deterministic methods.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2004년도 학술.기술논문발표회
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• pp.113-117
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• 2004

We need the contingency cost in order to deal with the uncertainty to be accompanied inevitably at the construction and an every kind risk not to forecast in advance. And also the contingency colt needed for the change order and we need it for reduction of the delay and reduce the trouble between owner and constructor. This study, through checking and analyzing the risk factor, in the step of domestic construction, suggests optimal management reserve to specific business about the contract type and the scale. The main results of this research are summarized as follow. First, I investigated the recognition about the contingency cost, grasped the risk to be happened at the construction step and found out the frequency occurrence, through making up question to engineer are carrying out their job in the domestic construction. Second, I computed optimal contingency cost rate by the statistics investigation, and proposed an improvement plan and problem when compute a contingency cost.