• Earthquakes and Structures
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• v.12 no.1
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• pp.119-133
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• 2017

Several theoretical and analytical formulations for the prediction of shear strength in reinforced concrete (RC) beam-to-column joints have been recently developed. Some of these predictive models are included in the most recent seismic codes and currently used in practical design. On the other hand, the influence of the stiffness and strength degradations in RC joints on the seismic performance of RC framed buildings has been only marginally studied, and it is generally neglected in practice-oriented seismic analysis. To investigate such influence, this paper proposes a numerical description for representing the cyclic response of RC exterior joints. This is then used in nonlinear numerical simulations of RC frames subjected to earthquake loading. According to the proposed strategy, RC joints are modelled using nonlinear rotational spring elements with strength and stiffness degradations and limited ductility under cyclic loading. The proposed joint model has been firstly calibrated against the results from experimental tests on 12 RC exterior joints. Subsequently, nonlinear static and dynamic analyses have been carried out on two-, three- and four-storey RC frames, which represent realistic existing structures designed according to old standards. The numerical results confirm that the global seismic response of the analysed RC frames is strongly affected by the hysteretic damage in the beam-to-column joints, which determines the failure mode of the frames. This highlights that neglecting the effects of joints damage may potentially lead to non-conservative seismic assessment of existing RC framed structures.

• Nuclear Engineering and Technology
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• v.56 no.9
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• pp.3950-3960
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• 2024

As a solution to the problem of spent nuclear fuels (SNFs), the disposal of SNF has gained attention from nations using nuclear energy because of hazards posed to the ecosystem. Among many proposed solutions, the most promising method is to dispose of SNF in a deep geological repository (DGR) which utilizes the multi-barrier concept developed by Finland and Sweden. Here, a new fully-coupled Thermal-Hydraulic (TH) code HADES (High-level rAdionuclide Disposal Evaluation Simulator) is developed using the MOOSE framework. This new code suggests basic numerical tools, such as a non-linear solver and finite element discretization, to assess the safety performance of disposal systems. The new TH code considered various TH behavior using Richards' flow approach, assuming gas pressure is constant. The HADES showed promising results when it was compared to various TH codes validated from DECOVAELX-THMC projects. When the single-canister model was utilized to estimate the TH behavior of the Korean Reference disposal System, although it showed significant saturation reduction due to the evaporation of water, the temperature was maintained under the thermal criteria limit, which is 100 ℃. In addition, the new code estimated temperature and degree of saturation of the multi-canisters model, considering two or three canisters, it showed a slightly lower temperature, 5 ℃, than the single-canister model. From these results, the following are concluded: (1) the new TH code contribute to an additional integrity by estimating TH behavior of KRS; (2) however, due to limitations in single-canister simulation, it is recommended to use multi-canisters simulation to estimate TH behavior accurately. Therefore, this model is anticipated not only to help licensing applications and estimation of various multi-physics phenomena and multi-canister at the disposal site.

• Nuclear Engineering and Technology
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• v.47 no.1
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• pp.11-25
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• 2015

The accident at Japan's Fukushima Daiichi nuclear power plant in March 2011, caused by an earthquake and a subsequent tsunami, resulted in a failure of the power systems that are needed to cool the reactors at the plant. The accident progression in the absence of heat removal systems caused Units 1-3 to undergo fuel melting. Containment pressurization and hydrogen explosions ultimately resulted in the escape of radioactivity from reactor containments into the atmosphere and ocean. Problems in containment venting operation, leakage from primary containment boundary to the reactor building, improper functioning of standby gas treatment system (SGTS), unmitigated hydrogen accumulation in the reactor building were identified as some of the reasons those added-up in the severity of the accident. The Fukushima accident not only initiated worldwide demand for installation of adequate control and mitigation measures to minimize the potential source term to the environment but also advocated assessment of the existing mitigation systems performance behavior under a wide range of postulated accident scenarios. The uncertainty in estimating the released fraction of the radionuclides due to the Fukushima accident also underlined the need for comprehensive understanding of fission product behavior as a function of the thermal hydraulic conditions and the type of gaseous, aqueous, and solid materials available for interaction, e.g., gas components, decontamination paint, aerosols, and water pools. In the light of the Fukushima accident, additional experimental needs identified for hydrogen and fission product issues need to be investigated in an integrated and optimized way. Additionally, as more and more passive safety systems, such as passive autocatalytic recombiners and filtered containment venting systems are being retrofitted in current reactors and also planned for future reactors, identified hydrogen and fission product issues will need to be coupled with the operation of passive safety systems in phenomena oriented and coupled effects experiments. In the present paper, potential hydrogen and fission product issues raised by the Fukushima accident are discussed. The discussion focuses on hydrogen and fission product behavior inside nuclear power plant containments under severe accident conditions. The relevant experimental investigations conducted in the technical scale containment THAI (thermal hydraulics, hydrogen, aerosols, and iodine) test facility (9.2 m high, 3.2 m in diameter, and $60m^3$ volume) are discussed in the light of the Fukushima accident.

• Journal of Society of Preventive Korean Medicine
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• v.28 no.1
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• pp.69-87
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• 2024

Objectives : This study is to investigate the current National Health Insurance Database cohort studies related to complications of Parkinson's Disease (PD) and suggest the design of Korean medical epidemiological studies of PD. Methods : Nationwide longitudinal studies of PD patients in South Korea were collected through Pubmed and the Korea Citation Index (KCI). We selected cohort studies that used the National Health Insurance Database in Korea and targeted Parkinson's disease patients. Studies published before February 2024 were categorized according to study designs. We examined variables and covariates, enroll dates and matching methods. Results : Of a total of 536 studies, 18 studies met the inclusion criteria. All studies used the National Health Insurance (NHI) Research Database and among them, 5 used sample data and one senior database. Studies can be classified into two types. 11 cohort studies were comparing PD patients and non-PD patients. Another type was 4 PD patients cohort studies. Most studies used two diagnostic codes (G20 and V124) for inclusion criteria. Enroll periods were from 2002 to 2017, and follow-up periods were from 7 to 14 years. 16 studies considered age and sex as covariates. 15 studies used the propensity score matching method to increase the level of causality. There was only one study related to the Korean medical treatment. Conclusion : In future cohort studies on Korean medical treatment, more attempts should be made to reveal the effect of the treatments on PD patients by defining inclusion criteria for patient groups, covariates, exposure variables, and assessment indicators more operatively.

• Korean Journal of Clinical Pharmacy
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• v.20 no.3
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• pp.213-220
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• 2010

Therapeutic duplication (TD) is a serious problem that frequently occurring primarily in the ambulatory setting in Korea. Implementation of concurrent drug utilization review (DUR) is a promising way to reduce inappropriate prescription and dispensing, and improve patient safety. This study was aimed to develop the process of DUR module of TD. Sixty-five drug ingredients classified into the drug category of the antipyretic, analgesic, and anti-inflammatory drug approved in Korea (The KFDA-dess nated classification codes of 114 or 264) were reviewed for this purpose. The drug ingredients (and products) were reclassified based on WHO's Anatomical, Therapeutic and Chemical (ATC) classification system. The clinical practice guidelines, textbooks and product labels on therapeutic uses of these drugs in Korea and several fores n countries were reviewed. If the drugs were categorized into the same therapeutically duplicable class, they were defined not to be used concurrently because the concurrent use was "therapeutically duplicated (unnecessary or even harmful)". Among the studied drug products, the following 5 drug classes were considto beas "therapeutic duplication": (1), on-t tooid DURnti-inflammatory drugs (NSAIDs, including s Dicylates), (2),Anilidts, (3),Opioids, (4) Ergot Dk Doids and (5) 5-$HT_1$ receptor agonot s. Therefore, concurrent prescribing or dispensing of more than 2 drug ingredients any in the above same classes should be considered as TD and needed to be warrant for careful review by pharmacists before dispensing.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.2
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• pp.153-164
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• 2014

Currently, there are many programs which are now being developed or already developed to predict radionuclide and corrosion product at the stage of designing NPP. However, since there are not many developments in evaluating quantity of activation corrosion products occurring when disassembling a nuclear power plant there exist some difficulties in calculating accurately. In order to evaluate activation products inventory for the research of effect of neutron activation in the reactor vessel, component of nuclear reactor and adjacent structures, it should be evaluated by using operation history of nuclear reactor, material composition of structure and average neutron flux in every field representing fixed structure of nuclear reactor. In this study, CORA, PACTOLE, CRUDSIM, CREAT and ACE codes are analyzed to predict the quantity of radionuclide and corrosion product of primary reactor which is used at the stage of designing. As a future study, the accuracy in calculating the quantity of product corrosion can be increase by finding out the possibility of use and improvement for evaluation of the decontamination.

• The Journal of Korean Medicine
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• v.45 no.3
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• pp.54-64
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• 2024

Objectives: Tonifying herbal medicines are used to nourish and balance the body's qi, blood, yin, and yang, targeting deficiencies. They are the second most frequently used category by consumers visiting Korean medicine clinics, following prescriptions for back pain. This study aimed to analyze the adverse events associated with herbal medicine products classified as tonics through a national pharmacovigilance database. Methods: We investigated 11 types of tonifying herbal medicine products (466 product codes) in the Korea Adverse Event Reporting System (KAERS) database from 2012 to 2021. Extracted adverse event reports were analyzed based on information of reports, patient demographics, classification of adverse events, reported herbal medicine products, and causality assessment results. Results: A total of 31 individual case safety reports were identified, covering 33 adverse events. The annual number of reports has increased over the study period. Most reports were filed by physicians and pharmacists, with the majority of patients being adults or elderly. Gastrointestinal disorders were the most frequently reported adverse events, accounting for 48.5% of cases. Of the 33 adverse events, 93.9% were classified as non-serious, while 6.1% were classified as serious. The most frequently reported herbal medicine products were Bojungikgi-tang, Yukmijihwang-tang, and Palmijihwang-tang. Conclusions: Although the study found that adverse events associated with tonifying herbal medicine products are generally not serious, it highlights the importance of systematic monitoring and reporting. The findings underscore the need for improved adverse event reporting systems within traditional Korean medicine to ensure patient safety and guide future research.

• Wind and Structures
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• v.27 no.3
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• pp.163-173
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• 2018

The design wind pressure for low-rise buildings in the ASCE 7-10 is defined by procedures that are categorized into the Main Wind Force-Resisting System (MWFRS) and the Components and Cladding (C&C). Some of these procedures were originally developed based on steel portal frames of industrial buildings, while the residential structures are a completely different structural system, most of which are designed as low-rise light-frame wood constructions. The purpose of this study is to discuss the rationality (or irrationality) of the extension of the wind loads calculated by the ASCE 7-10 to the light-frame wood residential buildings that represent the most vulnerable structures under extreme wind conditions. To serve this purpose, the same approach as used in the development of Chapter 28 of the ASCE 7-10 that envelops peak responses is adopted in the present study. Database-assisted design (DAD) methodology is used by applying the dynamic wind loads from Louisiana State University (LSU) database on a typical residential building model to assess the applicability of the standard by comparing the induced responses. Rather than the postulated critical member demands on the industrial building such as the bending moments at the knee, the maximum values at the critical points for wood frame buildings under wind loads are used as indicators for the comparison. Then, the critical members are identified through these indicators in terms of the displacement or the uplift force at connections and roof envelope. As a result, some situations for each of the ASCE 7 procedures yielding unconservative wind loads on the typical low-rise residential building are identified.

• Journal of radiological science and technology
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• v.44 no.5
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• pp.495-502
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• 2021

This study aims to provide basic data for elderly health insurance policy and medical radiation safety management by analyzing the general radiography usage and exposure dose of the elderly in Korea. The effective dose for each general radiography was calculated using the ALARA-GR program for 260 general radiography codes selected from 'National Health Insurance Care Benefit Cost'. The usage of general radiography was analyzed in the 2016 elderly patient data of the Health Insurance Review and Assessment Service, and the effective dose for each general radiography was applied. The general radiography usage and exposure dose per person aged 65 years and over was 6.47 cases and 0.56 mSv. Females showed higher value than males as 7.15 cases and 0.66 mSv(p<.001). By age, those between 75 and 79 showed the highest number as 6.97 cases and 0.62 mSv(p<.001). Those who were supported by Medical Aid showed higher value than those who were insured by National Health Insurance as 8.82 cases and 0.76 mSv(p<.001). In addition, the ratio by radiography was in the order of Chest 20.85%, Knee Joint 15.58%, and L-spine 14.67%, and the exposure dose was L-spine 29.40%, Chest 15.82%, Abdomen 7.97%, and Entire Spine 7.20%. General radiography, which is widely used due to the high frequency of diseases in the elderly population should be taken into consideration when establishing health insurance policies. In addition, it is necessary to check whether the general radiography with high exposure dose is performed as a routine examination without considering medical necessity.

• Korean Journal of Clinical Pharmacy
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• v.32 no.3
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• pp.155-165
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• 2022

Background: Chronic obstructive pulmonary disease (COPD) is not completely reversible and requires long-term management with appropriate treatment. This study aimed to analyze trends in treatment regimens and medication costs for COPD patients using a national claims database. Methods: We conducted this analysis using National Patient Sample data from the Health Insurance Review and Assessment Service covering the period from 2015 to 2018. We have constructed a dataset comprising COPD disease classification codes J43.x and J44.x (based on KCD-7 code, J43.0 was excluded) and compiled a list of drugs fitting current guidelines. To identify trends, we calculated frequency, ratio, and compound annual growth rate (CAGR) using the numbers of prescriptions and patients. Results: The number of COPD patients was 7,260 in 2018, slightly decreased from 2015. Most of these COPD patients were aged 60 or older and included a high proportion of males (72.2%; 2018). The number of patients prescribed inhaled medications increased gradually from 2015 to 2018 (9,227 (47.1%); 2015, 9,285 (51.5%); 2018), while the number of patients prescribed systemic beta-agonists and Xanthines has decreased since 2015 (CAGR -14.7; systemic beta-agonist, -5.8; Xanthines). The per capita cost of medication has increased by 0.4% (KRW 206,667; 2018, KRW 204,278; 2015) annually during the study period. Conclusion: This study showed that treatment with inhaled medications had continuously increased in accord with changing guidelines, but oral medications were still widely used. It is necessary to emphasize the importance of inhaled medications in treating COPD to reduce additional economic burden through appropriate medication use.