• Nuclear Engineering and Technology
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• v.49 no.2
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• pp.295-305
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• 2017

This paper reviews current status of the unified approach known as integrated safety assessment (ISA), as well as the associated SCAIS (simulation codes system for ISA) computer platform. These constitute a proposal, which is the result of collaborative action among the Nuclear Safety Council (CSN), University of Madrid (UPM), and NFQ Solutions S.L, aiming to allow independent regulatory verification of industry quantitative risk assessments. The content elaborates on discussions of the classical treatment of time in conventional probabilistic safety assessment (PSA) sequences and states important conclusions that can be used to avoid systematic and unacceptable underestimation of the failure exceedance frequencies. The unified ISA method meets this challenge by coupling deterministic and probabilistic mutual influences. The feasibility of the approach is illustrated with some examples of its application to a real size plant.

• Radiation Oncology Journal
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• v.37 no.4
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• pp.249-253
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• 2019

Purpose: We aimed to analyze the trend in intensity-modulated radiation therapy (IMRT) use in Korea from 2011 to 2018. Materials and Methods: We collected data from the Health and Insurance Review and Assessment Service (HIRA) big data based on the National Health Insurance Service claims and reimbursements records using primary treatment planning codes (HD 041) for IMRT from 2011 to 2018. We analyzed the changing patterns in clinical application to specific tumor sites and regional differences in IMRT utilization. Results: The use of IMRT has exhibited an 18-fold steep rise from 1,921 patients in 2011 to 34,759 in 2018. With regard to IMRT in 2018, 70% of patients (24,248/34,759) were treated in metropolitan areas (Seoul, Incheon, and Gyeonggi Province). IMRT was most commonly used to treat breast, lung, and prostate cancers in 2018. Among these, the use of IMRT for breast cancer shows the most remarkable increase from 2016 when the National Health Insurance began to cover IMRT for all solid tumors. Conclusion: The use of IMRT is steadily increasing to treat cancer and is concentrated in metropolitan areas.

• International Journal of Computer Science & Network Security
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• v.21 no.1
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• pp.12-18
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• 2021

This paper proposes a framework for the development of the health recommender system, designed to cater COVID-19 symptoms' self-assessment and monitoring as well as to provide recommendations for self-care and medical treatments. The aim is to provide an online platform for Patient Under Investigation (PUI) and close contacts with positive COVID-19 cases in Malaysia who are under home quarantine to perform daily self-assessment in order to monitor their own symptoms' development. To achieve this, three main phases of research methods have been conducted where interviews have been done to thirty former COVID-19 patients in order to investigate the symptoms and practices conducted by the Malaysia Ministry of Health (MOH) in assessing and monitoring COVID-19 patients who were under home quarantine. From the interviews, an algorithm using user-based collaborative filtering technique with Pearson correlation coefficient similarity measure is designed to cater the self-assessment and symptoms monitoring as well as providing recommendations for self-care treatments as well as medical interventions if the symptoms worsen during the 14-days quarantine. The proposed framework will involve the development of the health recommender system for COVID-19 self-assessment and treatments using the progressive web application method with cloud database and PHP codes.

• Journal of Welding and Joining
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• v.34 no.6
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• pp.16-19
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• 2016

Needs for structural integrity procedure such as BS 7910, the nuclear industry document R6 Rev.4 and the European FITNET procedure are being increased in industry. Especially, BS 7910 allows metallic structures to be assessed on the basis of fracture mechanics analysis rather than strict adherence to design and fabricated codes. This study is to propose the flaw assessment to judge the toughness level of welding consumables at the development stage. The FCA welding consumables with YP 690MPa and CTOD over 0.25 mm have been developed and its allowable weld flaw size considering actually applied environment has been evaluated. Since the estimated allowable defect size is sufficiently detectable in nondestructive testing, the toughness of the developed material is judged to be appropriate and no problem in securing the structural integrity.

• Korean Journal of Clinical Pharmacy
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• v.27 no.3
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• pp.136-142
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• 2017

Background: Dementia is one of important social and economic healthcare issues in the aging age. Therefore, it signifies to analyze the relationship between chronic disease or cardiovascular drug use and the incidence of dementia to establish a basis for increasing or preventing the risk of dementia. The purpose of this study was to investigate the correlation between the prevalence of chronic diseases and the use of cardiovascular drugs in patients diagnosed with dementia. Methods: In this study, we used data from sample of elderly patients from the Health Insurance Review and Assessment Service. We analyzed by logistic regression analysis with age, gender, and medication as covariates. KCD-7 was used to diagnosis of the disease, and drugs were analyzed using ATC codes and Korean standardized drug classification codes. Results: A total of 1,276,331 patients were analyzed in the sample of the elderly population, of which 532,075 (41.7%) were male and 744,256 (58.3%) were female. The patients have the higher risk of dementia in the older, women, and lower socioeconomically status. Cerebral infarction and ischemic heart disease increases risk of dementia. Patients taking statins, angiotensin converting enzyme inhibitor (ACEI) or angiotensin II receptor antagonists (ARB) showed low incidence of dementia. Conclusion: This study has been shown that ACEI, ARB, and statin drugs may associate with lower incidence of Alzheimer's and other dementia except vascular dementia.

• Wind and Structures
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• v.29 no.3
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• pp.209-223
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• 2019

The assessment of wind-induced vibration for tall reinforced concrete (RC) buildings requires the accurate estimation of their dynamic properties, e.g., the fundamental vibration periods and damping ratios. In this study, RC frame-shear wall systems designed under gravity and wind loadings have been evaluated by utilising 3D FE modelling incorporating eigen-analysis to obtain the elastic periods of vibration. The conducted parameters consist of the number of storeys, the plan aspect ratio (AR) of buildings, the core dimensions, the space efficiency (SE), and the leasing depth (LD) between the internal central core and outer frames. This analysis provides a reliable basis for further investigating the effects of these parameters and establishing new formulas for predicting the fundamental vibration periods by using regression analyses on the obtained results. The proposed constrained numerically based formula for vibration periods of tall RC frame-shear wall office buildings in terms of the height of buildings reasonably agrees with some cited formulas for vibration period from design codes and standards. However, the same proposed formula has a high discrepancy with other cited formulas from the rest of design codes and standards. Also, the proposed formula agrees well with some cited experimentally based formulas.

• Nuclear Engineering and Technology
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• v.50 no.2
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• pp.280-291
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• 2018

In the framework of OECD/NEA Working Group on Fuel Safety, a RIA fuel-rod-code Benchmark Phase I was organized in 2010-2013. It consisted of four experiments on highly irradiated fuel rodlets tested under different experimental conditions. This benchmark revealed the need to better understand the basic models incorporated in each code for realistic simulation of the complicated integral RIA tests with high burnup fuel rods. A second phase of the benchmark (Phase II) was thus launched early in 2014, which has been organized in two complementary activities: (1) comparison of the results of different simulations on simplified cases in order to provide additional bases for understanding the differences in modelling of the concerned phenomena; (2) assessment of the uncertainty of the results. The present paper provides a summary and conclusions of the second activity of the Benchmark Phase II, which is based on the input uncertainty propagation methodology. The main conclusion is that uncertainties cannot fully explain the difference between the code predictions. Finally, based on the RIA benchmark Phase-I and Phase-II conclusions, some recommendations are made.

• Nuclear Engineering and Technology
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• v.56 no.8
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• pp.3435-3449
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• 2024

Considering that system analysis codes are used for the evaluation of the performance of Passive Safety Systems (PSSs), it is important to investigate the capability of the system analysis code to reliably predict the heat transfer and natural circulation flow, which are the main phenomena governing the performance of a PSS. Since MARS-KS has been widely validated for heat transfer models, this study focuses on evaluating its capability to predict the single and two-phase pressure drops and natural circulation flow. The straight pipe simulation results indicate that the pressure drop predictions are reliable within ±5 % error margin for the single-phase flow and the errors of pressure drop up to - 30 % for the two-phase flow. Through single-phase natural circulation flow analysis, it is concluded that the use of the appropriate K-factor modeling based on the flow regimes is important since the natural circulation flow rate in MARS-KS is mainly affected by the form loss factor modeling. With two-phase natural circulation flow analysis, this study emphasizes the behavior of the system could change significantly depending on the two-phase wall friction and pressure loss modeling. With the analysis results, modeling considerations for the PSS performance evaluation with the system analysis codes are proposed.

• Journal of Korean Society of Steel Construction
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• v.21 no.6
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• pp.553-561
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• 2009

Risk analysis of highway sign supporting structures and sound barriers was done. Stochastic wind load was modeled by using extreme value distribution from site measurement and the variability of structural parameters was considered. Limit state functions were defined to assess structural stability by wind and risk of highway facilities was analyzed by combining wind hazard. According to the numerical analysis results, sound barrier post shows significantly higher risk than highway sign supporting structures. This is caused by the fact that the design codes of the structures are different. To distribute wind induced risk in highway structures, unification and improvement of design codes are required based on risk assessment.

• Earthquakes and Structures
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• v.12 no.3
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• pp.359-374
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• 2017

The seismic events in Northern Italy, May 2012, have revealed the seismic vulnerability of typical Italian precast industrial buildings. The aim of this paper is to present a seismic fragility model for Italian RC precast buildings, to be used in earthquake loss estimation and seismic risk assessment by comparing two building typologies and three different codes: D.M. 3-03-1975, D.M. 16-01-1996 and current Italian building code that has been released in 2008. Based on geometric characteristics and design procedure applied, ten different building classes were identified. A Monte Carlo simulation was performed for each building class in order to generate the building stock used for the development of fragility curves trough analytical method. The probabilistic distributions of geometry were mainly obtained from data collected from 650 field surveys, while the material properties were deduced from the code in place at the time of construction or from expert opinion. The structures were modelled in 2D frameworks; since the past seismic events have identified the beam-column connection as the weakest element of precast buildings, two different modelling solutions were adopted to develop fragility curves: a simple model with post processing required to detect connection collapse and an innovative modelling solution able to reproduce the real behaviour of the connection during the analysis. Fragility curves were derived using both nonlinear static and dynamic analysis.