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This paper analyses carbon emissions and value-added embodied in trade between two large developed countries, South Korea and the United States, during 2000-2014. Using multi-regional input-output (MRIO) tables, our analysis reveals that carbon emissions and value-added embodied in exports grew by 19% and 101% for South Korea but shrank by 43% and 7% for the United States. As a result, South Korea experienced a 40% increase in net carbon exports and 243% increase in net valueadded exports. At the industry level, the primary drivers of changes in carbon exports were electricity and basic materials. The majority of industries in witnessed improvements in carbon intensities suggesting improved environmental efficiency. While both countries achieved a decoupling of carbon emissions from value-added exports, substantial year-to-year and sectoral variations were observed. Finally, structural decomposition analysis indicates that domestic supply-side factors played a role in decreasing emissions whereas foreign demand-side factors contributed to emissions increases. In line with the main findings, various implications for policy and future research are discussed. [ABSTRACT FROM AUTHOR]

The relationship between natural cycles and human actions in causing climate change and its impacts on society have been a subject of debate. This paper explores the responses of pre-modern Koreans to climate change and natural disasters. The focus of this paper is on the societal reactions to these natural calamities and disasters during the Koryŏ dynasty (936–1392 A.D.) and their influence on Korea afterwards. This paper investigates the reasons behind the retention of primal religious worldviews in the face of ecological crises while other major imported religions were abandoned. The research method involved in this paper is archival research, and the literature sources include ancient records and other ecotheological resources. Through an analysis of the archival research and ecotheological resources, this study sheds light on the interpretation of climatic events in pre-modern Korea. Furthermore, based on the research findings, it presents missional implications for the Korean church in the post-pandemic era. This study underscores the importance of the church's responses to environmental awareness, collective responsibility, and spiritual support in addressing the challenges of climate change and provides missional implications for the Korean Church in response to the post-COVID-19 era based on the results of the research. [ABSTRACT FROM AUTHOR]

In South Korea, the rapid proliferation of smartphones has led to an uptick in messenger phishing attacks associated with electronic communication financial scams. In response to this, various phishing detection algorithms have been proposed. However, collecting messenger phishing data poses challenges due to concerns about its potential use in criminal activities. Consequently, a Korean phishing dataset can be composed of imbalanced data, where the number of general messages might outnumber the phishing ones. This class imbalance problem and data scarcity can lead to overfitting issues, making it difficult to achieve high performance. To solve this problem, this paper proposes a phishing messages classification method using Biased Discriminant Analysis without resorting to data augmentation techniques. In this paper, by optimizing the parameters for BDA, we achieved exceptionally high performances in the phishing messages classification experiment, with 95.45% for Recall and 96.85% for the BA metric. Moreover, when compared with other algorithms, the proposed method demonstrated robustness against overfitting due to the class imbalance problem and exhibited minimal performance disparity between training and testing datasets. [ABSTRACT FROM AUTHOR]

Christianity does not have as long of a history as other monotheistic religions and traditional ideologies in Korea, but—especially from the end of the 19th century—its new concepts have had a huge impact on the basic thoughts of Korean society. This paper focuses on the effects of Christianity and the activity of Christian communities on women's lives. According to my preliminary findings, in the late 1800s, the Christian missionaries and their newly formed communities offered opportunities for girls and women to get education, a profession, access to better health care, and learn self-care. After the complicated decades between 1910 and 1950, South Korea was experiencing remarkable changes, and Christians were an active part of this rebuilding, helping the lives of those who were struggling with poverty, lack of daily necessities, education, and health care. This paper aims to examine the thoughts and actions of Korean Christian communities towards decisions on childbirth, children out of wedlock, adoption, and single motherhood. This study investigates the approaches of South Korean Christian communities towards women related to the above-mentioned circumstances, focusing on the early examples and the last five to six decades. It is assumed that even though South Korea is now considered a modernized country, the government sometimes fails to cope with current problems, and traditional notions are still strong in familial matters. Therefore, not obeying conventional forms may cause social conflicts, or the decisions are hidden because of taboos and stigmas. This research is based on the publications of Christian communities and involves documentaries and case studies, including the baby box operation and adoption. This paper contributes to the expanding studies on Korean Christian communities, highlighting the social norms and their changes generated by new religious thoughts, while giving an insight into the daily struggles of Korean women's lives when it comes to decision-making about their motherhood. [ABSTRACT FROM AUTHOR]

The relationship between modernization and religion is contested, with the literature differing in how and in what ways religion helps or hinders countries' social, economic, and political development. This paper draws upon the history of Christianity in South Korea to critically explore the links between religion and modernization. It makes two arguments. First, discussions of the link between religion and modernization frequently employ static definitions of religion, but Christianity is characterized by oscillations between worldly (institutionalizing) and unworldly (countercultural) impulses that theoretically make very different contributions to social, economic, and political development. Second, in the case of South Korea, it is shown that both impulses have made vital contributions to the country's modernization at different times. This suggests that the dynamic tug-of-war between the institutional and countercultural facets of Korean Christianity, although problematic for individual believers and religious leaders, helped it become an important contributor to the country's success story. However, this paper concludes on a cautionary note by warning that extreme instances of these impulses have caused cleavages between Christianity and the Korean state and society and could undermine its future contributions. This suggests that diversity and toleration—a hallmark of Korean Christianity—will continue to be the best pathway forward. [ABSTRACT FROM AUTHOR]

The collaboration relationships between innovation actors at a geographic level may be considered as grouping two separate layers, the domestic and the foreign. At the level of each layer, the relationships and the actors involved constitute a Triple Helix game. The paper distinguished three levels of analysis: the global grouping together all actors, the domestic grouping together domestic actors, and the foreign related to only actors from partner countries. Bibliographic records data from the Web of Science for South Korea and West Africa breakdown per innovation actors and distinguishing domestic and international collaboration are analyzed with game theory. The core, the Shapley value, and the nucleolus are computed at the three levels to measure the synergy between actors. The synergy operates more in South Korea than in West Africa; the government is more present in West Africa than in South Korea; domestic actors create more synergy in South Korea, but foreign more in West Africa; South Korea can consume all the foreign synergy, which is not the case of West Africa. Research data are limited to publication records; techniques and methods used may be extended to other research outputs. West African governments should increase their investment in science, technology, and innovation to benefit more from the synergy their innovation actors contributed at the foreign level. However, the results of the current study may not be sufficient to prove that greater investment will yield benefits from foreign synergies. This paper uses game theory to assess innovation systems by computing the contribution of foreign actors to knowledge production at an area level. It proposes an indicator to this end. [ABSTRACT FROM AUTHOR]

Background: Despite the significance of demand forecasting accuracy for the registered nurse (RN) workforce, few studies have evaluated past forecasts. Purpose: This paper examined the ex post accuracy of past forecasting studies focusing on RN demand and explored its determinants on the accuracy of demand forecasts. Methods: Data were collected by systematically reviewing national reports or articles on RN demand forecasts. The mean absolute percentage error (MAPE) was measured for forecasting error by comparing the forecast with the actual demand (employed RNs). Nonparametric tests, the Mann‒Whitney test, and the Kruskal‒Wallis test were used to analyze the differences in the MAPE according to the variables, which are methodological and researcher factors. Results: A total of 105 forecast horizons and 196 forecasts were analyzed. The average MAPE of the total forecast horizon was 34.8%. Among the methodological factors, the most common determinant affecting forecast accuracy was the RN productivity assumption. The longer the length of the forecast horizon was, the greater the MAPE was. The longer the length of the data period was, the greater the MAPE was. Moreover, there was no significant difference among the researchers' factors. Conclusions: To improve demand forecast accuracy, future studies need to accurately measure RN workload and productivity in a manner consistent with the real world. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to clarify the concept of pediatric hospice and palliative care through conceptual analysis. It also sought to identify the differences between related concepts such as pediatric death care and pediatric spiritual care, in order to provide foundational data for the development of nursing theory and knowledge. Methods: A conceptual analysis of pediatric hospice and palliative care was conducted using Rodgers’ evolutionary method. Out of 5,013 papers identified, 28 were selected for detailed reading and analysis. Results: Pediatric hospice and palliative care encompasses physical, psychological, social, mental, spiritual, and family care for children with acute and chronic diseases with uncertain prognoses ahead of death, as well as their families. Effective pediatric hospice and palliative care will require multidisciplinary team nursing, effective communication, and supportive policies. Conclusion: The findings of this study suggest that providing pediatric hospice and palliative care will lead to improvements in pain relief for children and families, the efficiency of responses to death in children, and the quality of life for children and families. The significance of this study is that it clearly clarifies the concept by analyzing pediatric hospice and palliative care using an evolutionary method. [ABSTRACT FROM AUTHOR]

South Korea's remarkable success in controlling the spread of COVID-19 during the pre-Omicron period was based on extensive contact tracing and large-scale testing. Here we suggest a general criterion for tracing and testing based on South Korea's experience, and propose a new framework to assess tracing and testing. We reviewed papers on South Korea's response to COVID-19 to capture its concept of tracing and testing. South Korea expanded its testing capabilities to enable group tracing combined with preemptive testing, and to conduct open testing. According to our proposed model, COVID-19 cases are classified into 4 types: confirmed in quarantine, source known, source unknown, and unidentified. The proportion of the first two case types among confirmed cases is defined as "traced proportion", and used as the indicator of tracing and testing effectiveness. In conclusion, South Korea successfully suppressed COVID-19 transmission by maintaining a high traced proportion (> 60%) using group tracing in conjunction with preemptive testing as a complementary strategy to traditional contact tracing. [ABSTRACT FROM AUTHOR]

The use of renewable energy sources to achieve carbon neutrality is increasing. However, the uncertainty and volatility of renewable resources are causing problems in power systems. Flexible and low-carbon resources such as Energy Storage Systems (ESSs) are essential for solving the problems of power systems and achieving greenhouse gas reduction goals. However, ESSs are not being installed because of Korea's fuel-based electricity market. To address this issue, this paper presents a method for determining the optimal investment timing of Battery Energy Storage Systems (BESSs) using the Least Squares Monte Carlo (LSMC) method. A case study is conducted considering the System Marginal Price (SMP) and Capacity Payment (CP), which are electricity rates in Korea. Revenue is calculated through the arbitrage of a 10 MW/40 MWh lithium-ion BESS, and linear programming optimization is performed for ESS scheduling to maximize revenue. The ESS revenue with uncertainty is modeled as a stochastic process using Geometric Brownian Motion (GBM), and the optimal time to invest in an ESS is determined using an LSMC simulation considering investment costs. The proposed method can be used as a decision-making tool for ESS investors to provide information on facility investments in arbitrage situations. [ABSTRACT FROM AUTHOR]

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]

Social media not only changes the traditional communication environment but also brings new changes to agenda-setting. The main body of agenda-setting has shifted from the traditional media to the politicians, political parties and grassroots people. With the increasing use of social bots in public opinion manipulation and political election interference, whether they can participate in or influence agenda-setting has become an urgent concern. So far, there has been less literature focusing on engagement in agenda-setting for social bots. This paper studies the social media discussion content of the South Korean presidential election, determines the participation of social bots, and explores the connection between media agenda, bot agenda, and public agenda from the perspective of agenda setting. This study finds that while the main agendas of media, social bots, and the public are not the same, their agendas are relevant. In addition, the media agenda is not timely ahead of the bot agenda and the public agenda, and the time order only appears between the social bots and the public. [ABSTRACT FROM AUTHOR]

(1) Background: Among Korean research papers there have been studies on the correlation between tuberculosis-hypertension and diabetes and the correlation between dementia-hypertension and diabetes, but there were no analysis data specifically on tuberculosis and dementia. (2) Methods: A total of 2992 tuberculosis patients in the Gyeongbuk region were analyzed through a final analysis of integrated disease and health management system data collected from 2021 to 2022. In this selection, patients with tuberculosis under 50 years of age and 368 people diagnosed with tuberculosis were excluded. (3) Results: From 2021 to 2022, among the 2992 tuberculosis patients in Gyeongsangbuk-do aged 50 or older, 2722 (91.0%) belonged to the general tuberculosis patient group, while 270 (9.0%) belonged to the dementia–tuberculosis patient group. The average age in the dementia–tuberculosis group was 81.4 years, significantly higher than the general group's average of 75.7 years. Within the dementia–tuberculosis patient group, 235 patients (87.0%) had underlying medical conditions in addition to dementia and tuberculosis. The tuberculosis treatment cure rate was 56.3% (1477 patients) in the general group and 38.9% (105 patients) in the dementia–tuberculosis patient group. (4) Conclusions: The cure rate was notably higher in the general group. Similarly, the mortality rate (deaths due to tuberculosis) was significantly higher in the dementia–tuberculosis patient group (7.0%, 19 patients) compared to the normal group (3.0%, 81 patients). The mortality rate in the dementia group was more than twice that of the general group. [ABSTRACT FROM AUTHOR]

This study investigates the impact of digital textbooks, which play an important role in post-COVID-19 digitalized education, on the development of elementary school students' affective and social competencies. The study quantitatively analyzed three years of student panel data collected from 1,418 students in the third and fourth grades of a digital textbook pilot elementary school in South Korea. This study examined differences in the development of affective and social competencies between the treatment group (n = 708), who used digital textbooks for three years, and the control group (n = 710), who used digital textbooks for two years and returned to paper textbooks. Results showed that the affective competencies of self-efficacy, learning motivation, and learning attitudes were higher in the treatment group than in the control group, and the social competencies of communication, collaboration, and sociability were also higher. Implications for digital education research and related policies are provided, and limitations and suggestions for future research are discussed. [ABSTRACT FROM AUTHOR]

This paper proposes a method for forecasting surface solar irradiance (SSI), the most critical factor in solar photovoltaic (PV) power generation. The proposed method uses 16-channel data obtained by the GEO-KOMPSAT-2A (GK2A) satellite of South Korea as the main data for SSI forecasting. To determine feature variables related to SSI from the 16-channel data, the differences and ratios between the channels were utilized. Additionally, to consider the fundamental characteristics of SSI originating from the sun, solar geometry parameters, such as solar declination (SD), solar elevation angle (SEA), and extraterrestrial solar radiation (ESR), were used. Deep learning-based feature selection (Deep-FS) was employed to select appropriate feature variables that affect SSI from various feature variables extracted from the 16-channel data. Lastly, spatio-temporal deep learning models, such as convolutional neural network–long short-term memory (CNN-LSTM) and CNN–gated recurrent unit (CNN-GRU), which can simultaneously reflect temporal and spatial characteristics, were used to forecast SSI. Experiments conducted to verify the proposed method against conventional methods confirmed that the proposed method delivers superior SSI forecasting performance. [ABSTRACT FROM AUTHOR]

Background: The residual life of a patient with human immunodeficiency virus (HIV) is of major interest to patients and their physicians. While existing analyses of HIV patient survival focus mostly on data collected at baseline, residual life analysis allows for dynamic analysis based on additional data collected over a period of time. As survival times typically exhibit a right-skewed distribution, the median provides a more useful summary of the underlying distribution than the mean. In this paper, we propose an efficient inference procedure that fits a semiparametric quantile regression model assessing the effect of longitudinal biomarkers on the residual life of HIV patients until the development of dyslipidemia, a disease becoming more prevalent among those with HIV. Methods: For estimation of model parameters, we propose an induced smoothing method that smooths nonsmooth estimating functions based on check functions. For variance estimation, we propose an efficient resampling-based estimator. The proposed estimators are theoretically justified. Simulation studies are used to evaluate their finite sample performances, including their prediction accuracy. We analyze the Korea HIV/AIDS cohort study data to examine the effects of CD4 (cluster of differentiation 4) cell count on the residual life of HIV patients to the onset of dyslipidemia. Results: The proposed estimator is shown to be consistent and normally distributed asymptotically. Under various simulation settings, our estimates are approximately unbiased. Their variances estimates are close to the empirical variances and their computational efficiency is superior to that of the nonsmooth counterparts. Two measures of prediction performance indicate that our method adequately reflects the dynamic character of longitudinal biomarkers and residual life. The analysis of the Korea HIV/AIDS cohort study data shows that CD4 cell count is positively associated with residual life to the onset of dyslipidemia but the effect is not statistically significant. Conclusions: Our method enables direct prediction of residual lifetimes with a dynamic feature that accommodates data accumulated at different times. Our estimator significantly improves computational efficiency in variance estimation compared to the existing nonsmooth estimator. Analysis of the HIV/AIDS cohort study data reveals dynamic effects of CD4 cell count on the residual life to the onset of dyslipidemia. [ABSTRACT FROM AUTHOR]

This paper proposes a practical framework for developing a net-zero electricity mix scenario (NEMS), which considers detailed conditions for supply of each energy. NEMS means a path scenario for power generation amount by year of each generation resource required to achieve carbon neutrality in 2050. NEMS framework refers to a methodological framework that contains procedures and requirements to continuously update the NEMS by comprehensively reflecting policy changes. For evaluation of NEMS, indicators such as a system inertia resource ratio (SIRR) and a fuel conversion rate (FCR) are proposed. The proposed framework and indicators are applied for the 2050 NEMS in Korea's electricity sector. The SIRR, indicating the ratio of inertial resources to total resources, projects values of 49% and 15% for the years 2030 and 2050, respectively. Furthermore, the FCR, reflecting the ratio of fuel conversion for resources undergoing this process, predicts that all targeted resources will have completed conversion by the year 2043. [ABSTRACT FROM AUTHOR]

A new species of Cumacea belonging to the genus Dimorphostylis Zimmer was collected from the Dokdo and Ulleung Islands in the East Sea of Korea. The new species, Dimorphostylis pilocorpus sp. nov., can be distinguished from all other Dimorphostylis species by the combination of the body surface covered with numerous slender simple setae; carapace with one transverse, a pair of frontal, and three pairs of oblique ridges; three pairs of oblique ridges connected on a submedian carina; telson of the female with 1 pair of short simple and 1 short, stout simple seta centrally; 1 pair of stout simple and 3 pairs of short simple setae on the post-anal section; pleonite 5 of male with 1 spiniform seta on the ventral margin; post-anal section with 2 pairs of stout simple setae bearing a single subterminal setule on both sides; terminal margin with 3 stout simple setae; and a central seta slightly longer than the outer pair of setae. Full illustrations of the new species, including the mouthparts, are given in this paper. A key to the Korean species of Dimorphostylis is also provided. [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]

Objective: To determine age-related risk factors for chronic rhinosinusitis (CRS) with asthma. Methods: Data were obtained from a national survey of non-hospitalized civilians conducted by the Korean Center for Disease Control and Prevention. CRS diagnosis was based on the guidelines of the European Position Paper on Rhinosinusitis and Nasal Polyps 2020. Asthma was judged based on whether the patient had been diagnosed with asthma in the past. Of the 45,811 survey participants, 26,335 were included in the cross-sectional study. Participants included in the study were divided into the control, CRS, and CRS with asthma groups. Age-related risk factors were analyzed in patients aged < 60 or > 60 years. Univariate logistic analyses were performed to evaluate the relationship between groups. Risk factors included age, sex, household income, residence, education level, occupation, and body mass index (BMI). Results: Education level (Odds Ratio [OR]: 0.342, P =.0003), BMI (OR: 1.09, P =.0082), and total IgE (TIgE) levels (OR: 5.582, P =.003) were significantly different between the control and the CRS with asthma group. Education level (OR: 0.478, P =.0016) and TIgE levels (OR: 4, P =.0218) were significantly different between the CRS and CRS with asthma groups under 60 years of age. BMI (OR: 1.087, P =.0443; OR: 1.104, P =.0224) showed a significant difference between all three groups with age > 60 years. Conclusion: Progression to CRS with asthma is influenced by education level, occupation, and TIgE levels in patients under 60 years of age. BMI was the only influencing factor associated with the progression to CRS with asthma in those aged > 60 years. [ABSTRACT FROM AUTHOR]

This paper analyzes the expansion of social policies in South Korea during the context of globalization, by linking two theoretical approaches: social investment and the New Developmental State. Applying the case study method, I endorse the hypothesis of complementarily between the welfare state and the developmental state. The article shows that between the 1990s and the 2010s, South Korea expanded all sectors of social policies analyzed. Beyond the expansion of passive policies, active policies (including education) were reshaped in an integrated manner with the industrial policy to promote innovation, pursuing the transition to the knowledge-based society; also the family policy became one of the most generous among OECD countries. [ABSTRACT FROM AUTHOR]

This paper introduces an algorithm for approximating a set of data points with G 1 continuous arcs, leveraging covariance data associated with the points. Prior approaches to arc spline approximation typically assumed equal contribution from all data points, resulting in potential algorithmic instability when outliers are present. To address this challenge, we propose a robust method for arc spline approximation, taking into account the 2D covariance of each data point. Beginning with the definition of models and parameters for single-arc approximation , we extend the framework to support multiple-arc approximation for broader applicability. Finally, we validate the proposed algorithm using both synthetic noisy data and real-world data collected through vehicle experiments conducted in Sejong City, South Korea. • Proposal of model for single arc optimization. • Proposal of an optimization framework for multiple arc optimization. • Verification of proposed optimization algorithm via real-world dataset. [ABSTRACT FROM AUTHOR]

• Short-term distribution planning (S-DSP): Focus on the load transfer ability project. • MILP-based modeling: Incorporating diverse optimization techniques for S-DSP. • Pareto-front estimation: Enhancing S-DSP decision-making. • Empirical study in Korea: Practical application and insights. This paper presents an optimal Short-term Distribution System Planning (S-DSP) problem, with a particular focus on the load transfer ability project. Section 2 formulates the problem as a Mixed-Integer Linear Programming (MILP) optimization, considering the objective function of minimizing investment costs and non-switchable capacity, along with constraints like distribution system power flow, line capacity, and bus voltage. Section 3 extends the optimization problem into a multi-objective function-based approach using the Epsilon constraint method. In Section 4, we introduce a method for estimating the Pareto-front set and outline the decision-making process for selecting the optimal alternative. The proposed method's effectiveness is demonstrated through in-depth case studies, first with a 36-bus test system and then with a practical application to Korea's distribution system, which features 2056 buses and 2082 lines (Section 5 and Section 6). This research based on the empirical study underscores the practical applicability of the proposed S-DSP approach to the advance distribution management system (ADMS) in Korea. [ABSTRACT FROM AUTHOR]

• 'PF1, 6 and CS lifting Frame' and 'Sector lifting Tool' are designed and manufactured by Korea Domestic Agency (KODA). • The lifting tools were designed considering 2 times payload according to EN standard. • The structural integrity of lifting tools was verified by load test considering 1.5 times payload at least over 15 min. • The payloads of 1566 tones and 2028 tones were applied using hydraulic cylinders and customized jig structure. • All lifting tools were successfully withstood under required test load without defect or plastic deformation. Korea Domestic Agency (ITER Korea, KODA) has procured 44 kind's assembly tools for ITER project. The assembly tools are classified by the steel structure, lifting table and lifting accessory. 'PF 1, 6 and Central Solenoid Lifting Frame' (CS Lifting Frame) and 'Sector Lifting Tool' (SLT) are the representative assembly tool classified the lifting accessory. The assembly tools handle the heavy component which over 1,000 tones for payload. In this reason, the verification of the strength of the tools is very important and the integrity of lifting accessory tools was verified by not only structural analysis but also load test at factory under 1.5 times the payload for minimum 15 min. It is the requirements of the technical specification. The main role of PF 1, 6 and CS Lifting Frame is to lift and transfer the ITER components (PF1 coil, PF6 coil and CS coil) from the assembly hall to the tokamak fit and their temporary support positions. The CS coil is heaviest component in payloads handled by CS Lifting Frame. The weight is about 1,000 tones and CS Lifting Frame was verified by 1,500 tones load test. Sector Lifting Frame is to lift and transfer the 40° sector module from Sector Sub-Assembly Tool (SSAT) to tokamak fit. The sector module consists of Vacuum Vessel (VV), VV Thermal Shield and Two Toroidal Flied Coils. The total weight of the sector module is about 1,300 tones and Sector Lifting Frame was verified by 2,000 tones load test. The load test was carried out according to test procedure approved by IO. This paper describes the overall test method, customized test JIG and result of the lifting tools for handling heavy components of ITER. [ABSTRACT FROM AUTHOR]

The occurrence of many seismic events in energy production projects is caused by fluid injection-induced reactivation of critically stressed faults. The distribution of local stress regime has a significant influence on natural earthquakes, while its role in controlling injection-induced fault slip behavior and seismicity magnitude remains poorly understood. In this paper, we present a three-dimensional hydro-mechanical coupled fault reactivation study using unified pipe-interface element method (UP-IEM). The accuracy and reliability of the numerical method are evaluated and confirmed by numerical verification and actual observation data in Pohang EGS project, South Korea. The relationship between fault aseismic slip, seismic slip and seismicity magnitude is analyzed. Results show that both aseismic and seismic slip have different spatiotemporal distribution with the variation of stress regime. The seismic slip zone will exceed the pressurized area with the increase of initial slip tendency under the strike-slip-faulting stress regime ( σ H > σ v > σ h ). Compared with fluid pressure, the seismic slip is mainly determined by a sudden increase of the shear stress at the aseismic slip zone boundary. In addition, the location of the microseismic events moves towards the fluid pressure propagation front. The larger slip area and seismicity magnitude are easier to be induced under strike-slip-faulting stress regime than thrust-faulting stress regime ( σ H > σ h > σ v ). The tensile failure and higher permeability of the fault induced at injection phase for normal-faulting stress regime ( σ v > σ H > σ h ) leads to a greater seismogenic hazard at the shut-in stage. • A 3D injection-induced fault reactivation model is developed using UP-IEM. • The aseismic slip dominates the slip budget regardless the stress regime. • Seismicity is mainly controlled by sudden shear stress growth at aseismic zone edge. • The magnitude of the slip area and seismicity is normal-fault > strike-slip-fault > thrust-fault. [ABSTRACT FROM AUTHOR]

• The shield block is one of the main in-vessel components for the ITER. • A PA for the manufacturing and testing of the SBs have been made between ITER organization and Korea domestic agency. • Key technologies of the SB are raw material, precise machining, non-destructive examination and hot helium leak testing. The SB is one of the main in-vessel components manufactured with SS316L(N)-IG to play a major role in neutron shielding, to support the FW panels and to supply the FW panel with cooling water. Cooling channels are located inside of the SB to remove the neutron heat deposition while keeping the structure temperature to acceptable levels. The water coolant is routed first through the plasma-facing first wall panel which is attached to the SB and then through the SB. A number of deep slits are introduced into the SB to disrupt eddy current loops and reduce the Electro-Magnetic (EM) loads on the support system and VV. Water headers are machined on the side of the module with 7–10 mm welded cover plates. A Procurement Arrangements (PAs) for the manufacturing and testing of the SBs have been signed with Korea (50 %) and China (50 %). As part of the PA in Korean Domestic Agency (KODA), Process Qualification (PQ) to ensure the manufacturing and testing ability of the SB was completed successfully through manufacture of a Full Scale Prototype (FSP) as an essential step before starting series production. This paper reports key technologies, such as machining, welding, NDE and hot helium leak testing, of manufacturing and testing for the ITER SB series production in Korea toward successful completion of the missions. [ABSTRACT FROM AUTHOR]

In the effort to achieve carbon neutrality through a decentralized electricity market, accurate short-term load forecasting at low aggregation levels has become increasingly crucial for various market participants' strategies. Accurate probabilistic forecasts at low aggregation levels can improve peer-to-peer energy sharing, demand response, and the operation of reliable distribution networks. However, these applications require not only probabilistic demand forecasts, which involve quantification of the forecast uncertainty, but also determining which consumers to include in the aggregation to meet electricity supply at the forecast lead time. While research papers have been proposed on the supply side, no similar research has been conducted on the demand side. This paper presents a method for creating a portfolio that optimally aggregates demand for a given energy demand, minimizing forecast inaccuracy of overall low-level aggregation. Using probabilistic load forecasts produced by either ARMA-GARCH models or kernel density estimation (KDE), we propose three approaches to creating a portfolio of residential households' demand: Forecast Validated, Seasonal Residual, and Seasonal Similarity. An evaluation of probabilistic load forecasts demonstrates that all three approaches enhance the accuracy of forecasts produced by random portfolios, with the Seasonal Residual approach for Korea and Ireland outperforming the others in terms of accuracy and computational efficiency. • We proposed new low-voltage aggregation techniques based on portfolio theory to improve probabilistic demand forecasting. • The increased volatility at the low voltage level requires probabilistic forecasting to measure uncertainties. • The proposed methods were found to outperform random aggregation with the real-world data from Korea and Ireland. • A simple forecasting approach minimizing the standard deviation of deseasonalized demands was accurate and efficient. • The new method can contribute to achieving carbon neutrality, enable P2P energy sharing, and benefit prosumers. [ABSTRACT FROM AUTHOR]

· Design and analysis of the European test blanket modules (TBM): WCLL and HCCP. · Integral methodological framework for the simulation and structural integrity assessment of TBM. · Application of nuclear design code (RCC-MRx) to a plasma facing complex component. · Integrity assessment in a challenging design environment; new structural material, complex loads and tight margins. Two European Test Blanket Modules (TBM) concepts are being developed by F4E, the Water-Cooled Lithium Lead (WCLL) and the Helium-Cooled Ceramic Pebbles concept (HCCP, in collaboration with ITER KOREA). For both concepts, the ESTEYCO Mechanics team is responsible for designing and analyzing the TBM-box, which serves as the plasma-facing module for tritium breeding, and the TBM Shield in the WCLL concept. The design-by-analysis activities for these TBM-Sets are particularly challenging due to several factors. These include diverse and complex loads such as thermal, electromagnetic, pressure, and seismic loads, intricate failure modes to be assessed, the use of a new structural material (EUROFER 97) with limited available information, and the need to work within tight compliance margins in a restricted design space. Over the years, ESTEYCO has developed advanced methodologies to virtually test various design solutions systematically, coherently, and efficiently, aligning with the applicable nuclear design code (RCC-MRx). This paper provides an overview of key developments in simulating the TBM-Set under a comprehensive set of loads and subsequently assessing its structural integrity in an exceptionally detailed and comprehensive manner. The authors have created novel automated tools that encompass the entire process. These tools address tasks like distributing nuclear thermal loads, simulating cooling system behavior under operational conditions, characterizing and distributing electromagnetic loads, implementing code assessment rules for numerous evaluation points, and developing robust visualization tools for result analysis and validation. [ABSTRACT FROM AUTHOR]

This paper presents two data-driven virtual sensors to estimate the time-series of the probability of high-concentration occurrence of naturally occurring radioactive materials (NORMs; 238U and 222Rn) in groundwater based on the in-situ groundwater quality monitoring data and geological information. The random forest was applied to estimate the NORM concentration based on the actual in-situ groundwater quality data, rock type, and the aquifer depth. Additionally, this study proposes three data sampling techniques (i.e., under-sampling, synthetic minority over-sampling, and a complex sampling) to improve the model applicability and accuracy. The developed models were validated using the actual data acquired from 201 locations in South Korea. The models for 238U and 222Rn showed estimation accuracies of 85% and 80%, respectively; the models with over-sampling showed better performance. All the results verified the usefulness of the developed models as virtual sensors for providing immediate information on the in-situ presence of NORMs in groundwater. [Display omitted] • Naturally occurring radioactive material (NORMs) in groundwater can be problematic. • Virtual sensor for in-situ estimating the probability of high-concentration of NORMs. • Major geochemical factors for NORMs were evaluated using statistical analyses. • Methods for solving data imbalance problem in training virtual sensor were proposed. • Major factors for the estimation were consistent with the statistical analysis result. [ABSTRACT FROM AUTHOR]

• Employs non-identical parallel machines in manufacturing with multiple energy sources. • Designs a bi-objective model for a high-mix, low-volume production scheduling problem. • Provides Pareto-optimal solutions that minimize both total cost and carbon emissions. • Validates a model with real-world application to a manufacturer in Ulsan, South Korea. • Analyzes the effects of price fluctuations, different combinations of energy sources. This paper addresses the production scheduling problem with non-identical parallel machines in a high-mix, low-volume production environment with due dates, considering carbon emissions savings and diverse types of energy sources for machine operation. To this end, we present a bi-objective mixed-integer programming model that minimizes both the total production-related cost and the total carbon emissions in the production process to determine the optimal production strategy. For each machine, we consider various types of energy sources with different electricity generation costs and different amounts of carbon emissions. The proposed model is validated with an application to a manufacturer in Ulsan, the industrial capital of the Republic of Korea. Our results showcase the potential use of non-identical parallel machines to minimize the total cost and carbon emissions in green manufacturing. Furthermore, the results identify the trade-off between different energy sources and the total cost under different carbon emissions limits. Generally, as the carbon emissions limit increases, our proposed model tends to replace natural gas with coal to minimize the total cost. Also, we perform sensitivity analyses with respect to the energy price of different types of energy sources combined with nuclear and renewable energy sources. We find that coal provides more stability than natural gas in terms of the total cost, particularly when there are fluctuations in the price for coal and natural gas. Additionally, we determine the optimal combination of energy sources for various carbon emissions limits, aiming to minimize the total cost while simultaneously satisfying all production-related and environmental constraints. [ABSTRACT FROM AUTHOR]

Radiological Dispersal Devices (RDDs) are designed to disperse radioactive material over a wide area, leading to significant consequences to the environment and public health. This paper discusses the radiological effects of a potential RDD detonation containing 137Cs and 241Am in the commercial area of Busan, South Korea. The assessment, conducted with HotSpot Health Physics and RESRAD-RDD codes, found that summer had the most significant impact, with a maximum total effective dose equivalent (TEDE) of 280 mSv at 100 m and this decreased to 1 mSv at 4.5 km from the detonation point within the time interval of 35 min. • Designed Radioactive Dispersal Device using a mixture of radionuclides of 137Cs and 241Am. • Assessment of radiological impacts for various categories of people in the vicinity of the detonation of the RDD using the HotSpot Version 3.12 Health Physics code and the RESRAD-RDD code. • Stay times for the emergency workers during the RDD detonation. [ABSTRACT FROM AUTHOR]

This study investigates the international Photovoltaic Supply Chain (PVSC) from the perspective of the recent literature on Strategic Dependencies and Technological Sovereignty. In so doing, the paper fills existing literature gaps by providing: i) a fine-grained long-term analysis of the PVSC, considering all its segments and integrating production and technology dimensions; ii) detailed evidence of the changing hierarchical relationships within the supply chain; iii) an analysis of the drivers of strategic dependencies in the PVSC in different economic areas. Focusing on China, the EU, Japan, South Korea, and the US over the 2007–2021 period, the empirical evidence highlights the existence of strong strategic dependencies in the EU, especially in the mid and downstream segments of the PVSC. A similar, and in some cases even worse, situation is found in the US, although some diversification of the portfolio of suppliers, especially in the downstream, has been emerging in more recent years. These results have relevant implications in terms of policy theory with specific reference to EU and US initiatives in the field of industrial policies for sustainable transition. [ABSTRACT FROM AUTHOR]

This study was conducted to confirm the feasibility of using yellow poplar, which is a fast-growing hardwood species in Korea, as a structural material. Lumber was produced, and the mechanical grading and the knot diameter ratio on the wide surface measurement were performed for each grade of lumber. It was confirmed that the majority mechanical grades of yellow poplar were E10, E11, and E12, and the size of knot in the surface increased as the mechanical grades decreased. A fitted distribution of tensile strength of the lumbers was the Weibull distribution. As a result of calculating the tensile allowable stress using the 5th percentile value calculated by the Weibull distribution and the non-parametric method according to the mechanical grade, all the experimental values were higher than the minimum allowable stresses presented in the Korean industrial standards. However, for the low grades, there was no significant difference from the standard values. This was thought to be due to the large size of knots in low-grade lumber. It was expected that the prospect of using yellow poplar structural member will be higher if additional research is conducted on the restriction of knot size according to the mechanical grade. [ABSTRACT FROM AUTHOR]