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Recent experience with the strongest earthquakes greater than magnitude 5.4 in Korea leads to public interest in the safety and resilience of critical infrastructures. There are many nuclear power plants near the epicenters of the earthquakes. Nuclear power plants are essential infrastructures that provide stable and enough energy for human life, and simultaneously, control systems for the safety and security of nuclear power plants are critical due to the risk of nuclear accidents on public health and the environment. The nuclear area uses probabilistic risk assessment to estimate the risk of structures, systems, and components in nuclear power plants, and the evaluation of the fragility curve is a key process for probabilistic risk assessment. The challenges of a seismic fragility analysis lie in estimating the influence of various uncertainties in material, geometry, and earthquake and improving the existing fragility analysis methods, which require time-consuming nonlinear time history analysis. Thus, this paper conducts a multivariate seismic fragility analysis using surrogate models for reinforced concrete squat shear walls and proposes a simplified closed form equation for a chosen surrogate seismic demand model. The surrogate models are trained and validated by several approaches: response surface method, support vector machine, Gaussian process regression, and neural network. In addition, a correlation analysis is used to evaluate the relative importance of the variables to the seismic demand to simplify the surrogate model further. Finally, simplified surrogate models based on the importance of the variables are proposed as closed form of polynomials, and the performance of these models on the fragility analysis is evaluated. [ABSTRACT FROM AUTHOR]

Nurses' turnover intention has increased since the COVID-19 pandemic. Emotional labor is reportedly high among nurses in Korea, and a positive psychological capital can help reduce turnover intention. This cross-sectional study investigated the factors influencing turnover intention in nurses during the COVID-19 pandemic. Survey data were collected from 155 nurses caring for patients with COVID-19 at a university hospital in South Korea in March 2022. Self-reported and paper-based questionnaires on emotional labor, positive psychological capital, and turnover intention were employed. The mean values for emotional labor, positive psychological capital, and turnover intention were 54.52/80, 58.03/90, and 38.92/50, respectively, and 77.8% of nurses reported planning to quit working. Turnover intention correlated with emotional labor (r = 0.17; p = 0.041) and had no significant relationship with positive psychological capital. Sex (β = 0.24; p = 0.003) and emotional labor (β = 0.18; p = 0.019) affected turnover intention, with 9% explanatory power. Female nurses caring for patients with COVID-19 had a higher turnover intention than male nurses. Finally, the higher the emotional labor of nurses caring for patients with COVID-19, the higher the turnover intention. To reduce the turnover intention of nurses, hospitals need to help them enhance their emotional labor and positive psychological capital by establishing measures such as emotional coaching programs or psychological capital interventions. [ABSTRACT FROM AUTHOR]

Aims. This study aimed to analyze the effects of the surgery preparation time on patient outcomes. Background. Postoperative complications have a decisive effect on postoperative survival. The anesthesia time is a crucial determinant of such complications. Competent operating room nurses can shorten the surgery preparation time, which is the time from when anesthesia is first administered to the making of the surgical incision. The shortening of this preparation time can shorten the anesthesia time and may reduce postoperative complications. However, discussion of this preparation time is insufficient. Therefore, this study analyzed the effect of the surgery preparation time on patient outcomes. Methods. From electronic health records data, this retrospective cohort study used the data of 1,944 patients who had been immediately admitted to the ICU after their surgery between 2017 and 2020. The patients were divided into two groups: ≥30 minutes preparation time and <30 minutes preparation time groups. We performed chi-squared tests and t-tests to determine differences in preoperation, intraoperation, and postoperation characteristics of the patients and patient outcomes based on the surgery preparation time. Furthermore, we performed a multiple logistic regression by including 12 adjusted variables to determine the influence of the surgery preparation time on patient outcomes. Results. Among the 1,944 patients, 820 were in the ≥30 minutes preparation time group and 1,124 in the <30 minutes preparation time group. The multiple logistic regression analysis showed that the surgery preparation time affects alertness (OR = 1.44; 95% CI: [1.09, 1.90]), ventilator application (OR = 1.32; 95% CI: [1.03, 1.70]), and length of stay in the ICU (OR = 1.69; 95% CI [1.16, 2.47]). Conclusions. The surgery preparation time affects postoperative patient outcomes. The competence of operating room nurses is the most essential aspect of the surgery preparation time. Implications for Nursing Management. It is important to analyze operating room nurses' tasks, standardize the tasks, and educate nurses according to their experience level to reduce the surgery preparation time and improve patient outcomes. [ABSTRACT FROM AUTHOR]

South Korea was the first to administer the Indoor Air Quality Control Act in 1996, followed by Taiwan's implementation in 2012. This study investigated indoor air quality (IAQ) in public facilities before and after the enactment of Taiwan's Indoor Air Quality Management (IAQM) Act in 2012 to assess the effectiveness of the Act. The study also calculates health risks for employers, and consumers/visitors separately. The mean concentration of carbon dioxide (CO2) after the IAQM Act's enactment was higher than before, except for government offices. The lowest attainment rates for CO2, below 80%, were 73% in hospitals and 78% in libraries. As for formaldehyde, average concentrations were higher after the IAQM Act's implementation, except for the exhibition room and library. Notably, improvements in particulate matter with a diameter less than 2.5 μm (PM2.5) levels were evident in hospitals and libraries compared to other environments (attainment rates increased from 85% to 100% and 89% to 94%, respectively). However, in schools, preschools, and public transport spaces, unattainment rates worsened. Regarding cancer risk from formaldehyde exposure in the public, the 95% of upper risk limits ranged from 3.44 × 10 − 5 in the public transport system to 8.80 × 10 − 4 in preschools. Our findings highlight the necessity of integrating more measurement data after IAQM Act implementation and formulating management strategies based on risk assessments for future investigations. [ABSTRACT FROM AUTHOR]

Recently, smart intersections have emerged as a novel intelligent transportation system (ITS) solution that integrates traffic monitoring, optimal signal control, and even traffic safety. Although smart intersections have been prevalent in many cities, there are a few drawbacks in their practical operations. First, there are inevitable delays in transmitting and processing the video data. Second, there is still a need to develop a real-time signal control method leveraging the acquired data from smart intersections. Thus, this study aims to construct edge AI-based smart intersections and to provide their application for traffic signal coordination. To this end, we install smart intersections on three consecutive intersections of Route 45 in Pyeongtaek city, South Korea. The real-time traffic data are collected by an edge AI video analysis model which is compressed and optimized for its operation in on-site edge devices. The optimized model maintains a similar level of accuracy (93.64%), even if the size is reduced by 97.8% compared to the original. Next, we utilize the LT2 model to treat the coordination failure problem in nonpeak hours occurring unnecessary delays of the side-streets with relatively high demands. We complement some constraint conditions in order to consider the compatibility with the current legacy system. The experiment is conducted on a virtual environment of which geometry and traffic demand are configured based on the features of the study site. The numerical results conclude that the optimal offsets calculated by the LT2 model effectively manage bandwidths for multidirectional flows based on the real-time traffic demands collected from the edge AI-based smart intersections. This study contributes to serve high-resolution real-time traffic data using edge AI on smart intersections and to provide a case study for signal coordination. [ABSTRACT FROM AUTHOR]

Bereaved mothers with a deep bond to their sick child experience a distinct grieving process. This study delved into how Korean bereaved mothers come to terms with their child's death from cancer by exploring their bereavement and adaptation processes. In-depth interviews with 15 bereaved mothers yielded 14 subthemes within three overarching themes. These themes included the diverse coping mechanisms employed by the participants, attribution of meaning to their children's deaths, and personal growth intertwined with their experiences. These findings underscore the critical need for professional support to assist these mothers in their search for meaning and coping with the loss, particularly in the context of the unique cultural context of Korea. Understanding cultural variations is crucial for expanding the knowledge base in this field and advancing culturally informed interventions to support mothers who grapple with the loss of a child due to cancer across varied cultural settings. [ABSTRACT FROM AUTHOR]

Tick-borne virus detection in livestock and slaughterhouse animals has recently surged in the United States and Europe. Although cases of patients with tick-borne illnesses have been reported in Korea, food contamination from tick-borne viruses has yet to be investigated. Therefore, this study investigated severe fever with thrombocytopenia syndrome virus (SFTSV), tick-borne encephalitis virus (TBEV), and Crimean–Congo hemorrhagic fever virus (CCHFV) prevalence in meat and dairy products. A total of 628 products were collected from a Korean retail market during 2021–2022, including 195 beef, 130 goats, 90 lambs, 61 pork, 50 chicken, and 38 commercial cheese samples. In addition, 64 raw cow milk samples were collected from a ranch in Anseong-si, Gyeonggi-do, from 2021 to 2022. Real-time reverse transcription-polymerase chain reaction (RT-PCR), nested reverse transcription polymerase chain reaction (RT-nPCR), virus cultivation, and sequence analysis were conducted. SFTSV was detected in 1.53% (3/195) beef and 0.76% (1/130) goat meat samples with a low Ct value titer from 33.18 to 38.60. In contrast, SFTSV was neither detected in lamb, pork, chicken, raw milk, or cheese samples nor were TBEV and CCHFV detected in any of the tested samples. Although no existing cases or studies have indicated SFTSV transmittance through food, this study confirmed SFTSV genotype B RNA in SFTSV-positive meat samples. Therefore, monitoring for and evaluating SFTSV-contaminated meat products must be investigated in future studies. [ABSTRACT FROM AUTHOR]

Kori Unit 1 was permanently shut down on June 18, 2017. Since then, Korea is actively preparing for the decommissioning of the nuclear power plant. Because decommissioning work is performed in a radioactive environment, worker radiation exposure is a significant consideration. In this study, worker radiation exposure is evaluated during the steam generator, one of the heavy components of nuclear power plant, dismantling process. A radiation evaluation for the dismantling process is performed using the code RESRAD-BUILD. A steam generator dismantling scenario and optimal cutting method are designed to evaluate worker radiation exposure, considering pipe dimensions, cutting tool speed, and experience in steam generator replacement. The evaluation results are derived for each work type and year. As a result of the evaluation, worker radiation exposure is 7.5 man-mSv at the year of planned decommissioning. [ABSTRACT FROM AUTHOR]

We estimated the inhaled and deposited dose in humans using the International Commission on Radiological Protection (ICRP) and multiple-path particle dosimetry (MPPD) models following exposure to humidifier disinfectant containing polyhexamethylene guanidine (PHMG). The disinfectant has caused at least 1,810 deaths, with an odds ratio of lung injury of 47.3 (95% confidence interval: 6.1–369.7), because of its application in Korea. In this study, the Oxy product, which is regarded as the causative agent of most lung diseases, was sprayed into a cleanroom at normal (6.5 ppm in solution) and worst case (65 ppm in solution) dilutions; the airborne aerosol was monitored with direct reading instruments. Areas of deposition were divided into the head airway, tracheobronchial, and alveolar regions. Four dose scenarios were considered in this study: adults and children in both daily average and sleep conditions. Most PHMG aerosols were smaller than PM1 (96%). Number-based concentration analysis showed that <100 nm nanoparticles comprised 81% and 69% of the aerosol when the 6.5 and 65 ppm solutions were used, respectively. In all scenarios, the number-based deposited dose increased in the order of alveolar, tracheobronchial, and head airway regions; the mass-based deposited dose increased in the order of the head airway, alveolar, and tracheobronchial regions. The deposited dose per unit body weight was higher in children than in adults in terms of both number- and mass-based concentrations. When the humidifier was sprayed, the highest number-based concentration was found at a particle size of 15.4 nm; the highest deposition fraction or dose by PM1 was observed in the pulmonary and head airways in both models. [ABSTRACT FROM AUTHOR]

Background. Boston Scientific INGEVITY+ pacing lead (Boston Scientific, Marlborough, MA, USA) has been upgraded to INGEVITY. The performance of the INGEVITY+ pacing lead has not yet been reported. This study aimed to evaluate the short- and long-term safety, effectiveness, and handling experience of INGEVITY+ leads. Methods. Consecutive patients were included from 9 institutions in Korea, where 400 leads (200 right ventricular active fixation leads and 200 right atrial active fixation leads) were implanted or attempted in 200 subjects. Results. During the implantation, only one patient required a lead change because of lead screw failure. The handling questionnaires of the lead received very positive feedback with 88% of operators agreeing that it is easy for leads to pass through small vessels or vessels with multiple leads. At the 3-month follow-up, 95.7% of RA leads and 99.5% of RV leads had pacing thresholds less than 1.5 V. A total of 92.4% of atrial leads had amplitudes greater than 1.5 mV, and 96.5% of ventricular leads had sensing amplitudes greater than 5 mV at 3 months. A total of 99.8% had impedances between 300 and 1,300 ohms. The lead-related complication-free rate for all leads during follow-up was 100%, and the overall rates of lead dislodgment, perforation, and pericardial effusion were all 0.0%. Conclusions. The INGEVITY+ pacing lead exhibited exceptional clinical performance, with a high complication-free rate throughout the 3-month follow-up period. In addition, the lead displayed excellent electrical characteristics, and the lead-handling experience was reported to be very good. [ABSTRACT FROM AUTHOR]