• Journal of Radiation Protection and Research
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• v.47 no.1
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• pp.22-29
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• 2022

Background: A comprehensive, traceable, and easy-to-understand radiation risk indicator is desired for radiological protection. The early-onset hypothesis could be used for this purpose. Materials and Methods: An indicator for early death (IED) was developed and calculated using the epidemiological dataset from the 14^th Report of the Life Span Study (LSS) of Hiroshima and Nagasaki. By clarifying the calculation process, IED for all-cause mortality was estimated. In addition, the characteristics of IED for solid cancer mortality and cardiovascular mortality as well as those of men and women, and their dependence on age at exposure were investigated for detailed analysis. Results and Discussion: The IED for all-cause mortality was estimated to be approximately 4 years for an acute radiation exposure of 1 Gy regardless of the fitting dose range. The cumulative death rate for all solid cancers also indicated the early-death tendency (approximately 7-10 years at 1 Gy). Although, there is a slight difference in the characteristics of the risk obtained from the LSS study and this study, it is considered that the IED in a unit of years can also be used to show the overall picture of risk due to radiation exposure. Conclusion: We developed and calculated the indicator for early death, IED, for the cumulative mortality rate of all causes of death, all solid cancers, and circulatory diseases. The quantitative values of IED were estimated to be 4 years for all causes of death, 7-10 years for all solid cancers. IED has an advantage for intuitively understanding the meaning of radiation risk since it can be obtained by a simple and traceable method.

• Journal of Chest Surgery
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• v.56 no.2
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• pp.75-86
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• 2023

Background: We investigated the long-term outcomes of truncus arteriosus repair at a single institution with a 30-year study period. Methods: Patients who underwent repair of truncus arteriosus between 1993 and 2022 were reviewed retrospectively. Factors associated with early mortality, overall attrition, and reintervention were identified using appropriate statistical methods. Results: In total, 42 patients were enrolled in this study. The median age and weight at repair were 26 days and 3.5 kg, respectively. Thirty patients (71.4%) underwent 1-stage repair. There were 8 early deaths (19%). In the univariable analysis, undergoing surgery before 2011 was associated with early mortality (p=0.031). The overall survival rate at 10 years was 73.8%. In the multivariable analysis, significant truncal valve (TrV) dysfunction (p=0.010), longer cardiopulmonary bypass time (p=0.018), and the earlier era of surgery (p=0.004) were identified as risk factors for overall mortality. During follow-up, 47 reinterventions were required in 27 patients (64.3%). The freedom from all-cause reintervention rate at 10 years was 23.6%. In the multivariable analysis, associated arch obstruction (p<0.001) and significant TrV dysfunction (p=0.011) were identified as risk factors for all-cause reintervention. Arch obstruction (p=0.027) and a number of TrV cusps other than 3 (p=0.014) were identified as risk factors for right ventricle to pulmonary artery (RV-PA) reintervention, and significant TrV dysfunction was identified as a risk factor for TrV reintervention (p=0.002). Conclusion: Despite recent improvements in survival outcomes after repair of truncus arteriosus, RV-PA or TrV reinterventions were required in a significant number of patients during follow-up.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.4
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• pp.193-202
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• 2005

Marine risk assessment considers events such as collision/grounding, sinking/capsize, fire/explosion and flooding, developing relationships between their causes and effects. In addition, risk assessment of previously sunken ships are also necessary since they continuously have possibility for further oil spill or can cause other marine accidents. The objective of this paper is to develop the risk assessment systems for sunken ships to prevent oil spill and further marine causalities in order to preserve safe and clean oceans around Korea peninsula. The risk assessment systems for sunken ships comprise of database management sub-system for sunken ships, qualitative risk assessment sub-system, quantitative risk assessment sub-system, and cost-benefit analysis subsystem.

• Journal of the Korea Institute of Building Construction
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• v.14 no.5
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• pp.443-449
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• 2014

Although risk reduction of construction projects have been continued, the risk of fatal accident has been increased. The purpose of this paper is to reduce the cause of the essential risk factors. Questionnaire survey of construction companies in domestic was conducted and the Multiple Regression Analysis of statistics program was used to grasp effective factors among the risk factors of construction companies in domestic. Development of the essential risk factors and its application to projects could lead to improvements such as compression of network, reduction of cost, improvement of quality and reduction of safety accident.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.2
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• pp.170-178
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• 2024

This study aimed to quantitatively analyze the risk using data from 329 safety accidents that occurred in aquaculture fisheries management vessels over the recent five years (2018-2022). For quantitative risk analysis, the Bayesian network proposed by the International Maritime Organization (IMO) was used to analyze the risk level according to the fishing process and cause of safety accidents. Among the work processes, the fishing process was analyzed to have the highest risk, being 12.5 times that of the navigation, 2.7 times that of the maintenance, and 8.8 times that of the loading and unloading. Among the causes of accidents, the hull and working environment showed the highest risk, being 1.7 times that of fishing gear and equipment, 4.7 times that of machinery and equipment, and 9.4 times that of external environment. By quantitatively analyzing the safety accident risks for 64 combinations of these four work processes and four accident causes, this study provided fundamental data to reduce safety accidents occurring in aquaculture fisheries management vessels.

• Nutrition Research and Practice
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• v.14 no.5
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• pp.501-518
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• 2020

BACKGROUND/OBJECTIVES: Sodium intake is positively associated with blood pressure, which may increase the risk for cardiovascular disease (CVD). Therefore, we assessed the disease burden of CVD attributable to sodium intakes above 2,000 mg/day and prospectively investigated the association between dietary/urinary sodium levels and the risk of all-cause and CVD-mortality using the Korea National Health and Nutrition Examination Survey (KNHNES). SUBJECTS/METHODS: A total of 68,578 and 33,113 participants were included for comparative risk assessment (CRA) analysis and mortality analysis, respectively, and mean follow-up time for mortality was 5.4 years. CRA analysis was used to quantify attributable incidences of stroke, ischemic heart disease (IHD), and deaths attributable to sodium intake between 1998 and 2016. Cox proportional hazard regression model was used to determine the association between sodium intake and all-cause and CVD-mortality. RESULTS: Mean dietary sodium intake decreased over time, reaching 3,647 mg/day in 2016. Similarly, the population attributable fractions of stroke and IHD, and the number of CVD-associated deaths attributable to high sodium intake/excretion also decreased. In terms of association with mortality, when participants were grouped into quartiles (Q) by energy-adjusted sodium intake, those in Q2 had a lower risk of all-cause mortality than those in Q1 with lower intakes. The risk of CVD-associated mortality was higher only in females with high sodium intake in Q4 than those in Q1. CONCLUSIONS: This nationwide data indicates that, in line with previous studies of multiple cohorts, both low and high sodium intakes may be associated with an increased risk of mortality; therefore, the optimal sodium intake for Koreans needs to be revised.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.3
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• pp.481-490
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• 2010

The shock of melamine-contained food has been known with the incident of hospitalization or death of infants at the age of 11-month old in China. The purpose of this study was to examine consumers' risk perception, attitude and purchase behavior of melamine-contained food which recently came to the fore as a social issue, focusing on the relationship between consumers' attitude and purchase behavior based on physical risk, social risk, psychological risk, financial risk, consumers' attitude and purchase behavior. Study findings are as follows. First, the four factors of risk perception of melamine-contained food were significantly different by consumers. Consumers regarded social risk as most significant and it was followed by financial risk and psychological risk. And they regarded physical risk as most insignificant. Second, as for the difference of risk perception by demographic features, such factors as gender, age, marital status and schooling had no statistically significant influence. Third, the potential risk of melamine-contained food had a negative influence upon consumers' attitude and purchase behavior. In addition, consumers' attitude and purchase behavior were decided by perceived risks. This finding implies that consumers' attitude can accompany with negative or positive behavior and consumers' behavior can be related to social, financial and physical risks. Because the risk perception of melamine-contained food can cause consumers' distrust about all kinds of food in general, domestic manufacturers of milk product-contained confectionery and food can be harmed. In order to overcome this problem and make consumers purchase all the milk products and milk-contained food without fear, governmental agencies must reestablish systems with which the safety of imported raw materials and its processing can be insured and manufactures must improve the quality of products in a diverse and discriminative manner. This study seems to be meaningful in that it examined consumers' risk perception of melamine-contained food, a current social issue, and then looked into the influence of risk perception upon consumers" attitude and behavior, thus presenting the strategy of reestablishing the system of relationship between consumers and business entities in a desirable manner.

• Journal of Korean Society for Quality Management
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• v.44 no.2
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• pp.373-388
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• 2016

Purpose: This paper suggests a hierarchical time delay model to evaluate failure risks in FMEA(failure modes and effects analysis). In place of the conventional RPN(risk priority number), a more reasonable and objective risk metric is proposed under hierarchical failure cause structure considering time delay between a failure mode and its causes. Methods: The structure of failure modes and their corresponding causes are analyzed together with the time gaps between occurrences of causes and failures. Assuming the severity of a failure depends on the length of the delayed time for corrective action, a severity model is developed. Using the expected severity, a risk priority metric is defined. Results: For linear and quadratic types of severity, nice forms of expected severity are derived and a meaningful metric for risk evaluation is defined. Conclusion: The suggested REM(risk evaluation metric) provides a more reasonable and objective risk measure than the conventional RPN for FMEA.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6243-6247
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• 2015

Background: Thyroid cancer (TC) is a more common endocrine malignancy in females and is a major cause of death in developing countries. Therefore the aim of this study was to explore possible risk factors of thyroid cancer in females of Pakistan. Materials and Methods: This study covered 232 females, including 127 (54.7%) cases and 105 (45.2%) controls, from the INMOL Hospital and Sheikh Zayed Hospital, Lahore. Different risk factors were explored by the descriptive and inferentially statistics. Odds ratios and 95% confidence intervals for different risk factors were computed using logistic regression. Results: The results showed six risk factors, marital status, family history of thyroid cancer, iodine in the diet, oxidative stress, fast food and fried food, to demonstrate positive significant links to thyroid cancer (odds ratios and 95% confidence intervals of :2.152, 1.104-4.198; 2.630, 1.416-4.887; 2.391, 1.282-4.458; 4.115, 2.185-7.750; 3.656, 1.851-7.223; 2.357, 1.268-4.382; and 2.360, 1.199-4.643, respectively). Conclusions: The Oxidative stress, marital status, family history of cancer, fast food, use of iodine diet and fried food are the risk factors of thyroid cancer in females.

• Nuclear Engineering and Technology
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• v.44 no.5
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• pp.471-482
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• 2012

To assess the risk of nuclear power plant operation and to determine the risk impact of digital systems, there is a need to quantitatively assess the reliability of the digital systems in a justifiable manner. The Probabilistic Risk Analysis (PRA) is a tool which can reveal shortcomings of the NPP design in general and PRA analysts have not had sufficient guiding principles in modelling particular digital components malfunctions. Currently digital I&C systems are mostly analyzed simply and conventionally in PRA, based on failure mode and effects analysis and fault tree modelling. More dynamic approaches are still in the trial stage and can be difficult to apply in full scale PRA-models. As basic events CPU failures, application software failures and common cause failures (CCF) between identical components are modelled.The primary goal is to model dependencies. However, it is not clear which failure modes or system parts CCF:s should be postulated for. A clear distinction can be made between the treatment of protection and control systems. There is a general consensus that protection systems shall be included in PRA, while control systems can be treated in a limited manner. OECD/NEA CSNI Working Group on Risk Assessment (WGRisk) has set up a task group, called DIGREL, to develop taxonomy of failure modes of digital components for the purposes of PRA. The taxonomy is aimed to be the basis of future modelling and quantification efforts. It will also help to define a structure for data collection and to review PRA studies.