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The Korea Pathfinder Lunar Orbiter (KPLO), officially named as Danuri, is the Republic of Korea's first spacecraft to orbit the Moon. The goal of KPLO is to secure core deep space technology for future space exploration in Korea and contribute to lunar science by gathering data from the lunar orbit for one year. This paper presents the results of KPLO's Lunar Orbit Acquisition (LOA) phase in detail, with a particular focus on the operational results of Flight Dynamics (FD). During the LOA phase, the KPLO FD team experienced many expected and unexpected issues. These issues were mitigated by making real-time updates to the LOA phase Design Reference Mission (DRM). The paper also presents the results of the Orbit Determination (OD) and performance of each Lunar Orbit Insertion (LOI) maneuver conducted during the actual flight operation. The importance of considering operational constraints when designing the DRM is emphasized by presenting lessons learned based on actual flight experiences. Unlike the original KPLO LOA phase DRM, KPLO successfully achieved the final mission orbit using only three LOI burns, instead of the planned five LOI burns and an Orbit Trim Maneuver (OTM). Despite the extensive revisions made to the DRM, all mission requirements were still fulfilled during the final lunar orbit insertion, taking into account the significant operational constraints. • Real flight operation results of the Korea Pathfinder Lunar Orbiter's lunar orbit acquisition phase are presented. • Orbit determination and lunar orbit insertion maneuver performance are analyzed based on actual flight data. • Unexpected issues during the actual flight operation were mitigated through real-time updates on the design reference mission. • Considering real-world operational constraints while designing the design reference mission is very critical. [ABSTRACT FROM AUTHOR]

This paper explains the role of the Korean government's National R&D Program over three decades for fuel cell electric vehicle (FCEV) development. The R&D programs had started far before FCEV was considered feasible. We call this as a national pursuit, since the R&D programs has been participated by not only car manufacturers but also various research institutions, including universities, in Korea's national innovation system. The Korean government has implemented a series of National R&D Programs throughout many stages, from selection of technology, building infrastructure and legislations, demonstration, and subsidizing mass-produced FCEVs. The authors analyzed all the government R&D programs from 1989 to 2021 to show the evolutionary changes in contexts and contents of the programs that have reflected varying expectations, government's industrial strategy, and the maturity of technologies through periods. This paper claims that Korea's FCEV development has been regarded as a long-run national industrial strategy, and the development has been persistently pursued in a national innovation systemic manner, such as combining public R&D sector with industries and strong institutional and organizational supports by government. • South Korea's National R&D Programs have been at the center of the FCEV development. • The role of government is crucial in the early phase of novel technology development. • Visions for supporting the National R&D Programs have been elaborated along with technological advances. • R&D networks between large firms, universities, and GRIs formed through National R&D Programs. [ABSTRACT FROM AUTHOR]

A new radioactive ion-beam accelerator facility, RAON, is under construction in Korea. Among the seven experimental systems being built, the Large Acceptance Multi-Purpose Spectrometer (LAMPS) in the high-energy experimental hall is the versatile detector system for nuclear physics. Its primary goal is to study the nuclear equation of state (EoS) and the symmetry energy of the compressed nuclear matter, which should be essential to understand the effective nuclear interactions and structure of the astrophysical objects like neutron stars. The basic LAMPS system consists of the beam diagnostic elements such as the starting counters and beam drift chambers, the time-projection chamber, the barrel and forward time-of-flight systems, the forward neutron detector array, and the superconducting solenoid magnet. In this paper the overview of the present status of each detector component for LAMPS will be given with some prospects. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the association between media-based exposure to nonsuicidal self-injury (NSSI) and emergency department (ED) visits due to self-harm in Korea, specifically before and after the initial broadcast of the song Barcode, which has an explicit focus on NSSI. We used the national emergency department information system to obtain data related to ED visits due to self-harm between January 1, 2014, and December 31, 2018. Using interrupted time series regression analysis, we assessed the monthly ED visits due to self-harm before and after the media-based exposure to NSSI on March 30, 2018. In addition, self-harm methods were assessed. A total of 35,928,834 visits to ED were identified, of which 115,647 were due to self-harm. ED visits due to self-harm showed a significant step increase in the 10- to 14-year-old (β = 0.883, p =.001), 15- to 19-year-old (β = 2.941, p <.001), 20- to 24-year-old (β = 1.997, p = 0.002), and 25- to 29-year-old (β = 1.438, p =.029) age groups, before and after the media-based exposure to NSSI. The most pronounced increase was observed in male participants aged 20 to 24 years (β = 1.790, p =.012) and female participants aged 15 to 19 years (β = 5.158, p <.001). Self-harm by cutting has increased significantly in participants aged 10 to 29 years, and self-harm by poisoning has also increased significantly in participants aged 10 to 19 and 25 to 29 years. ED visits due to self-harm increased significantly, especially in adolescents and young adults, following the exposure to NSSI. Responsible media reporting on NSSI and appropriate guidelines would help prevent a further increase in self-harm. We worked to ensure sex and gender balance in the recruitment of human participants. We worked to ensure race, ethnic, and/or other types of diversity in the recruitment of human participants. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work. [ABSTRACT FROM AUTHOR]

This paper proposes an energy management system (EMS) for nanogrids to balance the power supply and forecasted demand in consideration of forecasting errors arising from high instantaneous demand. The proposed EMS employs a power-balancing optimization process for forecasted demand and a reference power modulation strategy for forecasting errors. This power-balancing optimization utilizes nanogrid sources, such as photovoltaics, fuel cells, and batteries, to meet forecasted demand and a supercapacitor charging process to overcome issues with a low energy density. The proposed reference power modulation strategy is utilized to allocate power from a hybrid energy storage system consisting of a battery and supercapacitor in order to compensate for forecasting errors. In addition, this proposed strategy considers battery and supercapacitor constraints such as the power changing rate and total power limitations. The power-balancing optimization process also operates at faster sampling rate than the reference power modulation process in order to improve the computational efficiency. The performance of the proposed EMS is evaluated using real data obtained from the Korea Electric Power Exchange. • This paper proposes a cascaded structure energy management system (EMS) for nanogrid to balance power for both forecasted demand and forecast errors including high instantaneous demand. • The proposed EMS comprises a power balancing optimization process for forecasted demand and reference power modulation strategy for the forecast errors. The power balancing optimization utilizes nanogrid sources, such as PV, fuel cell, and battery, to meet forecasted demand as well as a supercapacitor charging process for addressing low energy density characteristics. • The proposed reference power modulation strategy is utilized to allocate power from the HESS comprising a battery and supercapacitor, in order to compensate forecast errors. In addition, this proposed strategy is performed considering battery and supercapacitor constraints such as their power changing rate, total power limitation. [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]

Due to structural demographic shifts, declining population, economic restructuring and deindustrialization, the number of shrinking cities has been increasing in South Korea. To tackle these challenges, policy makers have promoted entrepreneurial environments, largely absent in such cities, to accelerate rates of revitalization by attracting talented young knowledge workers. The creation of collaborative coworking spaces is one of these policy responses. However, there have been rising concerns over whether such coworking spaces are producing the expected outcomes. It is uncertain whether policy makers are encouraging the development of coworking spaces without strong evidence of their effectiveness. The purpose of this paper is to find out what roles coworking spaces play in small and medium sized shrinking cities. A five-month study was conducted in 12 small and medium sized cities (<500,000 population) using two interrelated methods: 1) an online survey with users of coworking spaces in their 20s and 30s and 2) semi-structured interviews with the managing staff/owners of 4 coworking spaces. Based on the study, the research concludes that the coworking spaces played a key role in bringing young people together and helping them to start new businesses by providing proper hard and soft infrastructure, hosting events and sharing information and knowledge. • The emergence, concept and expected outcomes of coworking spaces in relation to urban revitalization. • The demographic changes, economic restructuring and the increasing number of shrinking cities in Korea. • An online survey with users of coworking spaces in their 20s and 30s. • Semi-structured interviews with managing staff/owners of coworking spaces. • The roles and limitations of coworking spaces in shrinking cities in Korea. [ABSTRACT FROM AUTHOR]

The 2022 South Korean presidential election campaign saw populist politicians, especially conservative parties, leverage gender conflicts and misogyny to attract young male swing voters. But there has been limited scholarly attention to the connection between gender and populist politics, particularly in South Korea, with research primarily focused on women's voting patterns, their political party representation, and on populist politics in the US, Europe, and Latin America. Existing research identifies that common strategies employed by populist politicians include anti-feminist discourses, reference to crises in masculinity, and appeals to emotion and affect. This paper examines how South Korean populist politics has utilized gender conflicts since democratization, considering the evolution of 'gender wars' in the South Korean context. It specifically delves into the strategies employed by conservative populist politicians from the People Power Party (PPP) during the 2022 election campaigns. These strategies, although similar to those of right-wing populists in Europe and the US, emphasized three key issues unique to South Korea: compulsory military service, low fertility rates, and the dismantling of the Ministry of Gender Equality and Family. This South Korean case contributes significantly to academic discussions about populist politics and gender, contextualized within the local political, social, and cultural context. [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]

• A cross-country analysis identifying risk and protective factors on the COVID-19 deaths. • Ranking of 100 countries based on the proposed pandemic containment effectiveness (PCE) score. • Positive relationship between the PCE score and economic growth in major economies. • A counterfactual analysis discussing the tradeoff between the PCE scores and GDP growth. This paper studies whether containing COVID-19 pandemic by stringent strategies deteriorates or saves economic growth. Since there are country-specific factors that could affect both economic growth and deaths due to COVID-19, we first start with a cross-country analysis on identifying risk and protective factors on the COVID-19 deaths using large across-country variation. Using data on 100 countries from 3 January to 27 November 2020 and taking into account the possibility of underreporting, we find that for deaths per million population, GDP per capita, population density, and income inequality are the three most important risk factors; government effectiveness, temperature, and hospital beds are the three most important protective factors. Second, inspired by the stochastic frontier literature, we construct a measure of pandemic containment effectiveness (PCE) after controlling for country-specific factors and rank countries by their PCE scores for deaths. Finally, by linking the PCE score with GDP growth data in Quarters 2 and 3 of 2020, we find that PCE is positively associated with economic growth in major economies. Countries with average PCE scores, such as Malaysia, would gain more GDP growth by 3.47 percentage points if they could improve their PCE scores for deaths to South Korea's level in Q2 of 2020. Therefore, there is not a trade-off between lives and livelihood facing by governments. Instead, to save economy, it is important to contain the pandemic first. Our conclusion is also mainly valid for infections due to COVID-19. [ABSTRACT FROM AUTHOR]

• Calorie labeling per menu item reduces consumer calorie consumption, while daily intake recommendations show similar effects. • When calorie labeling and daily intake recommendations are presented together, the reduction in calorie consumption is nullified. • The study underscores the complexity of influencing food choices through calorie information policies and the importance of strategic presentation. • Personality traits influence food choices, with extroverts opting for lower-calorie items and those with higher self-esteem and agreeableness choosing higher-calorie options. • Developing strategic calorie information policies is essential to effectively guide individuals toward healthier food choices in restaurant settings. This paper builds on the stream of research of the impact of caloric information on food choices and its implications for food and health policies. Specifically, the study explores the interaction between calorie labeling per menu and daily intake recommendations. By conducting a field experiment in South Korea, consumers were randomly approached to assess the effects of calorie-related information on food choices. The study reveals that offering either the daily calorie intake recommendation or specific calorie information on menu items reduces consumers' calorie consumption. Yet, when both types of information are presented concurrently, this effect is nullified. This implies that, in line with U.S. FDA regulations, presenting both daily calorie recommendations and specific calorie information on menu item in restaurants might not be an effective strategy for promoting lower calorie choices. The study also examines the influence of personality traits on food choice. Extroverts tend to choose lower-calorie items, while individuals with higher self-esteem and agreeableness and neuroticism traits prefer higher-calorie options. Good self-restraint is linked to lower-calorie choices. This research highlights the need for strategic calorie information policies in order to effectively guide individuals toward healthier choices. [ABSTRACT FROM AUTHOR]

In this paper, I argue that intersectionality can benefit the study of migrant urban citizenship and that migrants' legal status affects their potential for urban citizenships. These arguments are based on life story interviews I conducted with Mongolian labour migrant women (both documented and undocumented) living and working in Seoul during the COVID-19 pandemic. Drawing from this data, I first discuss the mutual relationship between COVID-19 regulations and the specific urban spaces they affected, and second, how migrant women navigated this relationship. In practice, I categorise these pandemic-driven experiences into three specific types of spaces – spaces of escape , spaces of fear , and spaces of (potential) discrimination – which I analyse through the lenses of gender, class, and racialisation. In conclusion, I call for future research on migrant urban citizenship to critically consider the role of legal status in migrants' embodied processes of urban citizenship-making and investigate how underlying structural social and power relations shape these embodied processes. Reformulating the concept of urban citizenship in a way that explicitly informs policy making and fosters migrants' embodied experiences of urban citizenship is also needed. • Intersectionality can benefit the study of migrant urban citizenship. • Migrants' legal status affects their potential for urban citizenship. • COVID-19 regulations transformed urban spaces in Seoul into spaces of escape, fear, or discrimination. • Migrant urban citizenship needs to be reconceptualised into a policy-oriented approach. [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]

In recent years, there have been several projects in the world to design and construct a diffraction-limited light source which pushes an emittance of electron beams in a storage ring close to an emittance of photon beams in the X-ray region to enhance brilliance by two orders of magnitude. In line with this trend, the Korea fourth-generation storage ring (Korea-4GSR) project was launched in 2021 to establish a new light source in the Republic of Korea with an ultra-low emittance of 50 pm rad at a beam energy of 4 GeV. For the Korea-4GSR project, a compact linear accelerator for generating 200 MeV and a booster synchrotron is chosen as an injector. The booster synchrotron ramps beam energy from 200 MeV to 4 GeV and the lattice is designed based on the FODO concept. It is crucial in the booster to achieve high beam quality for injection efficiency into a storage ring. Since the quality of the extracted beam relies on an energy ramping profile, the ramping process is important to be optimized. This paper represents the result of our studies on the effect of the energy ramping profile in the evolutionary physical process in a booster synchrotron. [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]

The purpose of this study is to provide direction and highlight implications for human rights education for creative arts therapists by exploring their experiences of human rights education designed to promote human rights sensitivity. Six creative arts therapists were recruited to participate in focus group interviews conducted online between August and September 2022. Additional interview data were collected until February 2023, and the data were transcribed afterward. This paper presents the qualitative part of a descriptive sequential mixed design. Qualitative analysis was performed to analyze the content, and a total of 5 main and 15 subthemes were identified. Taking the improvement in human rights sensitivity via education as the central phenomenon, we identified a pathway from expressing human rights sensitivity to directing human rights education for creative arts therapists. This pathway involved a factor that inhibited human rights sensitivity and a deficiency in human rights education. The results underscore the importance of supporting creative arts therapists in their occupational competencies by improving their sensitivity toward human rights and delivering human rights education that is aligned with their professional characteristics. • Research explored the human rights education experiences of creative arts therapists(CATs). • Expression of HR sensitivity was found to be related to social and cultural factors. • Organizational culture acted as one of the inhibiting factors for HR sensitivity. • Enhancement of HR sensitivity emerged as an effect of human rights education. • Human rights education tailored to the specialty and identity of CATs is required. [ABSTRACT FROM AUTHOR]

Addressing the rental affordability problem requires defining and measuring 'affordability' accurately. A variety of objective and subjective indicators have been suggested to measure rental affordability. However, several studies demonstrated that objective and subjective measures of rental affordability are not well aligned with each other, and the underlying cause of this mismatch is unknown. Drawing on Noll's (2013) objective and subjective social indicator framework, this paper examines the extent to which the objectively and subjectively measured levels of rental affordability are incongruent and the driver of the disparity. Using the longitudinal data of the Labor and Income Panel Study in Korea (2015–2020), we conducted a series of panel multinominal logistic regressions with fixed effects. The results show that there is a significant mismatch between objective and subjective rental affordability, and this incongruence is partly due to residential satisfaction, which influences subjective rental affordability. The paper calls for more in-depth exploration of residential satisfaction to benefit refined and nuanced policies to address rental affordability problems. • Objective rental affordability is not well aligned with subjective affordability. • The mismatch between the two indicators is partly due to residential satisfaction. • Residential satisfaction affects subjective rental affordability. [ABSTRACT FROM AUTHOR]

With the growing importance of renewable energy generating resources around the world, the government is working towards expanding the share of renewable energy to 20% of total power generation considering the limitation of coal-fired and nuclear generation by 2030 in South Korea. However, the growing number of wind generating resources being connected to the electrical power system presents a challenge for transmission grid planning to increase the penetration of wind power while maintaining high levels of reliability and security of the electrical power system. In this paper, we propose a probabilistic power output model of wind generating resources for network congestion management. We use the historical data from the wind farms located on Jeju Island in South Korea to fit the Weibull distribution and implement Monte Carlo simulations. The simulation results, which represent network congestion with probabilistic values, are applied to the empirically modeled power grid of Jeju Island and a steady-state security evaluation is performed. The proposed probabilistic approach will be a key role to reduce the risk of over-investment in power transmission facilities compared to the deterministic approach to develop the generation mix scenarios with high wind power penetrations. • A New probabilistic approach based on Monte Carlo Simulations is presented. • A practical process for probabilistic wind power output modeling is proposed. • Probabilistic security assessments for network congestion management are suggested. • An empirical data of Jeju Island's wind farms is considered for network congestion analysis. [ABSTRACT FROM AUTHOR]

Wind Generating Resources (WGRs) are variable, uncontrollable, and uncertain compared to traditional generating resources. As Wind Generating Resources (WGRs) have the intermittent nature of WGRs and uncertain characteristics according to the weather condition, the accurate prediction of WGRs' capacity factor is an essential factor associated with integrating a large amount of wind generating resources into the grid. As wind farm outputs depend on natural wind resources that vary over space and time, spatial correlation analysis is also needed to estimate power outputs of wind generation resources. In this paper, we propose the potential capacity factor estimates of new wind generating resources using the augmented spatial analysis and modelling of power outputs produced by wind farms that are geographically distributed in windy areas. To validate the proposed spatial prediction model, we use the empirical data from the Jeju Island's wind farms in South Korea. • A practical method for estimating capacity factors of target wind farms is presented. • An augmented spatial modeling techniques is proposed. • A new method for developing wind penetration scenarios is suggested. • An empirical data of Jeju Island's wind farms is considered for grid integration analysis. [ABSTRACT FROM AUTHOR]

This paper presents a contrastive approach to speaker-audience interaction in political speeches, specifically, in relation to culture. It begins with a review of seminal and subsequent research based in the UK, which has shown how speakers use rhetorical devices to invite audience responses, typically applause. This is followed by evaluation of political speech research set in other nations – both Eastern (Japan and South Korea) and Western (USA and European), English-speaking and non-English-speaking – investigating how the behaviour of speakers and audiences contrasts across cultures. Proposals include, that whereas speakers in Western nations predominantly use rhetorical devices to invite audience responses implicitly , their counterparts in East Asian nations are more inclined to use explicit invitations. Furthermore, whereas invited booing is a salient feature from observations of American and French political speeches, the same cannot be said of others, particularly Japan, where such behaviour is reportedly absent. Speech-making was once regarded as monologic, but studies reported herein show how political speeches can be considered dialogic, akin to how people in conversations take turns. However, it is shown here that behavioural specifics of this form of dialogue need to be understood in the context of culture. • Review of UK political speech research: speakers use rhetoric to invite applause. • Evaluation of comparable research set in other nations. • Includes Eastern (Japan/South Korea) and Western (European/USA). • How does the behaviour of speakers and audiences contrast across cultures? • Strong evidence for cultural differences in speaker rhetoric and audience responses. [ABSTRACT FROM AUTHOR]

• This paper investigate the dehumidification performance of MOFs desiccant coated heat exchanger. • Maximum water uptake capacity of MOFs desiccant was around 0.4 g•g−1 in given operating condition. • 90% of MOFs with 10% of solvent and binder mixture coated on the metallic fin of heat exchanger. • Increase of coating thickness can achieve the 131% of dehumidification performance. • The decrease of space velocity shows the over 160% enhancement of dehumidification performance. In this study, the comprehensive study of the performance investigation of Solid Desiccant Based Dehumidification (SDBD) system which involves the desiccant selection and desiccant coating with metallic heat exchanger was conducted at the mild humid conditions which represent the humid air conditions in summer, South Korea. The water uptake capacity of three different solid desiccants was investigated to find the proper solid desiccant in the SDBD system under the given operating conditions. Among the three different solid desiccants, the aluminum fumarate based metal organic frameworks (MOFs) was selected as the best solid desiccant for SDBD system and it has the maximum water uptake capacity around 0.398 g·g−1 for given operating conditions. The aluminum fumarate based metal organic frame works (MOFs) was coated on the metallic surface of heat exchanger by current developed coating method and the desiccant and binder solution is consistent of 10% of binder and solvent mixture and 90% of aluminum fumarate based MOFs. As a result, the increase of coating thickness from 0.05 mm to 0.2 mm and operating time from 150 s to 300 s can achieve the 113% and 131% of dehumidification performance enhancement in average, respectively. Remarkably, over 160% improvement of dehumidification performance in average can be achieved by the decrease of space velocity from 13 s−1 to 5.2 s−1. [ABSTRACT FROM AUTHOR]

Members of the armed forces rely on having an effective and efficient medical evacuation (MEDEVAC) process for evacuating casualties from the battlefield to medical treatment facilities during combat operations. Determining which MEDEVAC units to task to respond to incoming requests for service, known as the MEDEVAC dispatching problem, is a natural sequential decision making problem and is the focus of this paper. Unlike previous research in this area, this paper incorporates triage classification errors and the possibility of having blood transfusion kits on board select MEDEVAC units. A discounted, infinite-horizon continuous-time Markov decision process model is formulated to examine the MEDEVAC dispatching problem and to compare generated dispatching policies to the currently practiced United States military policy. We utilize an approximate dynamic programming (ADP) technique that leverages a random forest value function approximation within an approximate policy iteration algorithmic framework to develop high-quality policies for both small-scale and large-scale problem instances. A representative planning scenario involving joint combat operations in South Korea is developed and utilized to investigate the differences between the various policies. Results from the analysis indicate that applying ADP techniques can improve current practices by as much as 29% with regard to a life-saving performance metric. This research is of particular interest to the military medical community and can inform the procedures of future military MEDEVAC operations. [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]

Angelica gigas Nakai (A. gigas) is used as a traditional medicine in Korea and China. The root of A. gigas is most commonly prepared by decocting with water, and is used as a blood tonic, for the treatment of gynecological diseases, anti-inflammatory, analgesic and laxative. Thus, this paper presents a detailed review of the phytochemistry, botanical origin and pharmacological activities of A. gigas. Eleven monocoumarins, ten furocoumarins, eleven pyranocoumarins, nine volatile oils, nine flavonoids and six other constituents of A. gigas were summarized and discussed. The major chemical constituents of A. gigas , decursin and decursinol angelate, have also been detailed for their anti-inflammatory, anticancer, analgesic and sedative effects. This review aims to provide a reference for the future development and use of A. gigas. • The phytochemistry, and pharmacology of Angelica gigas Nakai were reviewed. • Fifty-six compounds from A. gigas were classified, and discussed. • Decursin, decursinol angelate, and decursinol are the main components. • The pharmacological effects of decursin and decursinol angelate were summarized. [ABSTRACT FROM AUTHOR]

• Exposure to harmful online content increases cyberbullying perpetration. • Parental support decreases cyberbullying perpetration. • Parental support moderates the effect of exposure to harmful online content on cyberbullying perpetration. • Parental support increases cyberbullying perpetration for at-risk students. Cyberbullying has grown into a global issue with the Internet becoming a readily accessible commodity around the world. During the outbreak and spread of novel coronavirus disease (COVID-19), most personal and professional activities shifted to the virtual environment, increasing the time children spent online and the opportunities to engage in deviant behavior such as cyberbullying. In this paper, we analyzed cyberbullying data drawn from a nationally representative survey of South Korean adolescents during the COVID-19 pandemic. Correlates of cyberbullying perpetration were examined in addition to the moderating impact of parental support. Policy implications and future research directions were discussed based on the findings. [ABSTRACT FROM AUTHOR]

According to the "differential vulnerability hypothesis," individuals in adverse socioeconomic circumstances as less mentally resilient to stressful events. However, several recent papers radically challenged this hypothesis based on the accumulated literature on stress inoculation and presented cases in which lower-SES adolescents appear to be less vulnerable to suicidal ideation in the face of interpersonal aggression. We re-examine the link between psychological vulnerability to acute stressors and SES using yearly longitudinal public survey data from South Korea. This is a secondary data analysis of a multi-year public health panel dataset on South Korean adolescents. Logistic regression is used to examine the association between suicidal ideation and a range of predictor variables, with a particular focus on the interaction between bullying victimhood and log family income. These variables and the sample were chosen for consistency with recent revisionist research. We reaffirm the well-established finding that bullying victimhood strongly and consistently increases the odds of suicidal ideation (OR = 1.859, p < 0.01). However, we find no evidence in favor of the traditional "differential vulnerability hypothesis" or the recently proposed counterhypothesis. A subsample analysis from the latest wave (W4–W5) did produce results that are consistent with recent revisionist findings, but we suggest this is likely a false positive. There appears to be no systematic association between SES and vulnerability to suicidal ideation in the face of peer aggression among South Korean adolescents. The claim that lower-SES adolescents may be more resilient to stressful events stands on limited empirical support. • Bullying victimhood is an important acute stressor of adolescent suicidal ideation. • Recent studies reported that higher SES raises vulnerability to suicidal ideation. • We conduct confirmatory analysis of the recent proposal with data from S. Korea. • We fail to find evidence that the effect of bullying victimhood varies by SES. • The idea that lower-SES adolescents are tougher stands on weak empirical support. [ABSTRACT FROM AUTHOR]

The Korea fourth-generation storage ring (Korea-4GSR) has a low electron beam emittance of 60 p.m.-rad, and provides a photon beam that is 100 times brighter and 100 times more coherent than the third-generation Pohang Light Source (PLS-II). However, the new source imposes a higher heat load on beamline optics. In particular, the first mirror (M1), which receives the broad-bandwidth white beam will be distorted by the thermal load from X-ray beam and the heat bump will degrade the beam quality. For the thermal analysis of M1, a method is developed to solve the thermal deformation with temperature gradient and absorbed power density. To implement the method in the analysis of heat load effect on M1, a benchmark study was performed on beamline 8A at PLS-II. In this paper, we describe the thermal analysis of M1 in Korea-4GSR after verifying our simulation method in a benchmark study. [ABSTRACT FROM AUTHOR]

This study investigates the impacts of carbon pricing policies on firms' greenhouse gas (GHG) emissions. We include two carbon pricing policies: carbon tax and emission trading scheme (ETS) at national and sub-national (province) levels, measured as policy existence (binary variable) and carbon price (continuous variable). Firms' GHG emissions are measured as total emissions and emission intensity. Using unique recent firm-level data from 2010 to 2021 from three East Asia countries (Japan, the Republic of Korea (ROK), and the People's Republic of China (PRC)), we obtain the following key findings. First, the national carbon pricing policy significantly reduced firms' GHG emissions and GHG emission intensity in Japan and the ROK. The greater the carbon price, the greater the impact. Second, the subnational carbon pricing policies implemented in two provinces of Japan (Saitama and Tokyo) decreased firms' GHG emissions. Third, heavy industry sectors such as energy, utilities, and industrials experienced a substantial decrease in GHG emission intensity due to the carbon pricing policy. Finally, our main results are robust to different model specifications and various measures of firms' GHG emissions. Although literature studying the ex-post impact of carbon pricing on emissions at country and sector-level is abundant, this paper contributes to the existing literature providing empirical evidence of the impact of carbon pricing policies on firms' emissions using firm-level data, which is highly limited especially in Asia. [ABSTRACT FROM AUTHOR]

Sloping walkways are common pedestrian traffic facilities in modern cities, especially, in some cities located in mountainous terrain, such as Hong Kong, and Zurich. Compared with level walkways, sloping walkways may lead to the decrease in pedestrian flow efficiency, and are more prone to trigger crowd disasters at extreme crowd densities, for example, recent crowd stampede event in Itaewon, South Korea, did happen on a narrow ramp with an extreme crowd density. Therefore, it is important to study pedestrian flow dynamics on ramps. In this paper, we conducted single-file pedestrian flow experiments in 0°, 3°, 5°, 7°, 9°, 12°, 17°, 22°, 27° uphill and downhill conditions, and analyzed contrastively the influence of walkway slope on pedestrian flow dynamics. Our main findings are as follows. (i) Pedestrian flow efficiency is the highest in 7° downhill condition, indicating that a small downhill slope is advantageous to pedestrian flowing. (ii) Whether it is uphill or downhill, the ramp steeper than 7° will significantly decrease pedestrian flow efficiency, therefore is disadvantageous to pedestrian flowing. (iii) For a ramp, uphill and downhill pedestrian flow efficiencies are not equal. Downhill pedestrian flow efficiency is always larger than uphill pedestrian flow efficiency. These findings provide important guidance for the design of sloping walkways and the safety management of pedestrian crowds on sloping walkways. • The influence of walkway slope on pedestrian flow is studied. • A slope pedestrian flow experiment is conducted. • A small downhill slope around 7°is most advantageous to pedestrian flowing. [ABSTRACT FROM AUTHOR]

Although research on time series prediction based on deep learning is being actively carried out in various industries, deep learning technology still has a high entry barrier for researchers who have not majored in computer science. This paper presents a tutorial on time series prediction using a deep learning-based model. The entire process of time series data prediction is presented—from data collection to evaluation of prediction results. The details of each step are shown through a case example of predicting peak electricity demand and system marginal price of Jeju Island in Korea using the 1D-CNN and BiLSTM model. In Jeju Island, the proportion of renewable energy in the total power generation capacity is increased to 67% in 2021, requiring more accurate electricity demand forecasts. Therefore, using 808 days of training data from February 2018, electricity demand and SMP for the next 21 days were predicted. To make it easier for readers to follow, the example uses only open public data, and the entire Python source code is shared via a GitHub repository. The prediction error calculated by WRMSSE showed 0.42 in electricity demand and 0.63 in SMP max. A WRMSSE value less than one means that the forecast was relatively good, that is, better than naïve forecasting. This tutorial is not limited to the energy industry but can be utilized for any application requiring time-series data prediction. This article is expected to be of great help to researchers who need to understand the process of time series prediction using deep learning and use it for application in their industry. [ABSTRACT FROM AUTHOR]

When artefacts of traditional cultural heritage are waterlogged due to floods and other disasters, they can be quickly protected from contamination by harmful fungi using irradiation treatments. In this study, we showed that Epicoccum nigrum has the potential to contaminate traditional heritage artefacts made of Korean paper and silk under waterlogged conditions. E. nigrum showed 60% lower mycelial growth in medium containing freshwater than in medium containing natural seawater. Control of this contamination was attempted using gamma and electron beam irradiation disinfection technology. The mycelial growth of E. nigrum irradiated with a 5 kGy dose of gamma rays was completely controlled at 15 kGy dose. Next, we evaluated the effect of irradiation on contaminated sample artefacts. E. nigrum growing on waterlogged sample artefacts of cultural heritage was completely controlled at 15 kGy in freshwater-immersed artefacts of Korean paper and silk and seawater-immersed silk. However, in Korean paper immersed in seawater, 15 kGy gamma-irradiation treatment did not control growth of the fungus. Our results suggest that at least 15 kGy of gamma radiation should be used to for treatment, to preserve waterlogged traditional cultural heritage artefacts of Korea, after flooding or other disasters involving water. • Epicoccum nigrum is a radiation-resistant contaminant of historical artefacts. • E. nigrum contamination occurs during fresh- or sea-waterlogging. • Treatment with 15 kGy GI or EBI completely controlled E. nigrum. • Irradiation control of E. nigrum may be dependent on sample composition. • GI and EBI are viable decontamination options against fungal attack. [ABSTRACT FROM AUTHOR]

In recent years, the frequency of power demand imbalance and negative price phenomenon has risen due to the rapid expansion of renewable energy sources (RES). Because of this, a means to reduce the curtailment of RES by utilizing surplus energy is essential. This paper focuses on reducing the curtailment of wind turbines (WT) with high output intermittency and minimizing the investment cost of IES via an integrated energy system (IES). The IES operation seeks to improve the acceptability and efficiency of the RES as it supports the integration of various energies mix, such as electricity, heat, hydrogen. This paper proposes an optimal facility combination set (FCS) of IES that satisfies the requirements of ISO and IPP using Multi-Objective Optimization Programming (MOP). The case study is based on a wind farm in South Korea, set in Aewol-eup, Jeju-Island. The case study results provide the best configuration of the IES energy mix with the best economic value and efficiency while satisfying ISO and IPP perspectives. • Derive the optimal design and operation solution for integrated energy systems. • Derive the optimal solution using multi-objective optimization programming. • Propose the optimal facility combination set of the integrated energy system. • Propose the consensus point between investors and users of IES. [ABSTRACT FROM AUTHOR]

• The integration with BIM and AR has the challenges of limited interoperability and complex data formats. • Open-source software and standardized data format are the solutions to overcome these issues. • The proposed architecture also provides various geometry processing and deep learning application. • The architecture was applied to workflow visualization and deformation detection in pipe maintenance. Informed decision-making is crucial for construction site operators. Cyber-physical systems, including various technologies such as augmented reality and building automation tools, are gathering popularity within the infrastructure management sector. However, they are expensive and inaccessible to adopt for most small organizations. This paper describes a prototype of low-cost mobile augmented reality service for BIM and demonstrated its usability for pipe maintenance by supporting inspection, workflow management, data reduction, and augmented reality. User views about the decision support, integration and ease of use of the prototype were also collected from the organisations in the UK and South Korea. The results showed that integrating the augmented reality service with the building automation tool connected to the BIM server enhances decision-making for on-site operations by generating a closed loop. This paper also highlights the need for developing low-cost digital solutions to foster the digitalization of construction organisations with limited budgets. [ABSTRACT FROM AUTHOR]

• Korea's first dynamic discrete event tree methodology-based tool, DICE, developed. • Validation shows DICE reproduces results of conventional event trees. • DICE simulation highlights potential in analyzing success criteria issues. Although conventional probabilistic safety assessment (PSA) makes a sufficient contribution to evaluating the safety of nuclear facilities, it suffers some limitations in performing optimal assessments close to the actual behavior by reflecting time dependencies in accident management. However, integrated deterministic and probabilistic safety assessment (IDPSA) literally combines two methodologies to enable synchronized evaluation based on physical behavior, system availability of facilities, and operator's response. Dynamic integrated consequence evaluation (DICE) is one of the IDPSA tools developed for this purpose, which is the first achievement in South Korea and supported by a regulatory authority. Based on dynamic discrete event tree (DDET) methodology, DICE consists of a scheduler that supports the exchange of information between modules, including a physical module that computes thermal-hydraulic simulations, a diagnosis module that specifies branching points for safety systems, and a reliability module that provides system availability. This paper deals with numerical validation comparing the conventional deterministic and probabilistic results for a sample scenario with those of DICE, and discusses an application of DICE to support and extend the scope of conventional PSA through a case study. It is expected that DICE emphasizes the compliance with conventional PSA methodologies while providing magnified perception in investigating unforeseen scenarios. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of incorporating spatiotemporal wind data on the performance of wind forecasting neural networks. While previous studies have shown that including spatial data enhances the accuracy of such models, limited research has explored the impact of different spatial and temporal scales of input wind data on the learnability of neural network models. In this study, convolutional neural networks (CNNs) are employed and trained using various scales of spatiotemporal wind data. The research demonstrates that using spatiotemporally correlated data from the surrounding area and past time steps for training a CNN favorably affects the predictive performance of the model. The study proposes correlation analyses, including autocorrelation and Pearson correlation analyses, to unveil the influence of spatiotemporal wind characteristics on the predictive performance of different CNN models. The spatiotemporal correlations and performances of CNN models are investigated in three regions: Korea, the USA, and the UK. The findings reveal that regions with smaller deviations of autocorrelation coefficients (ACC) are more favorable for CNNs to learn the regional and seasonal wind characteristics. Specifically, the regions of Korea, the USA, and the UK exhibit maximum standard deviations of ACCs of 0.100, 0.043, and 0.023, respectively. The CNNs wind prediction performances follow the reverse order of the regions: UK, USA, and Korea. This highlights the significant impact of regional and seasonal wind conditions on the performance of the prediction models. [Display omitted] • 3D CNN-based wind velocity prediction. • Estimation of CNN learnability through spatiotemporal wind correlation analysis. • Discovery of influence of local geometric and seasonal wind on CNN prediction. • The proposed correlation analysis can aid in selecting yaw-control wind farm sites. [ABSTRACT FROM AUTHOR]

• The change in the internal/external environment of the system can have an effect on the performance of PECCS. • This study has conducted the effect evaluation on performance issues as part of the performance evaluation methodology for PSS development. • Major performance issues (such as modeling of PECCS pressure, wall condensation in the system, and check valve) were identified through impact evaluation using the system analysis code, and the effects of major performance issues on the system were analyzed. • In this paper, the evaluation of performance issues has led to the identification of the main factors to consider in PECCS modeling. In this study, the effect of performance issues on the Passive Emergency Core Cooling System (PECCS), a type of Passive Safety System (PSS), was evaluated. The PECCS relies on natural phenomena such as gravity, density difference, and pressure difference to operate. Its driving force is lower compared to that of the active safety system, making it necessary to evaluate its performance in various transient situations. Major performance issues were identified through effect evaluation using a conceptual problem for the PECCS, and their effects on the system were analyzed using the system analysis code MARS-KS. Therefore, there are concerns about whether the PSS can sufficiently perform safety functions in various situations. In Korea, performance evaluation methodology for PSSs is being developed to dispel these concerns. As part of the methodology development, this study conducted the effect evaluation on performance issues. The study identified several major performance issues for the PECCS, including those related to pressure and heat loss of piping within the system, uncertainties in tank wall condensation modeling, and checks valve modeling. The evaluation of performance issues has led to the identification of the main factors to consider in PECCS modeling, which include: 1) the geometry and pressure drop of PECCS, 2) the occurrence of wall condensation in pipes and tanks, and 3) the behavior of check valves. Proper modeling of these factors is important in achieving accurate analysis results and preventing potential issues, such as premature check valve closure or incomplete coolant injection. In conclusion, the results of this study are expected to contribute to deriving safety analysis modeling guidelines for PSSs and design considerations for NPPs that utilize PSSs by improving the completeness of the developing performance evaluation methodology. [ABSTRACT FROM AUTHOR]

OTT streaming services have been restructuring the global multimedia industry, and there have been strategic actions and reactions among OTT players and traditional pay-TV platforms. This study found that Pricing and Content investments are key factors affecting market share and subscribership in global OTT markets, and M&As have positive effects on the two performance measures, although with less statistical confidence. OTT-specialized firms in the UK, Germany, France, Japan, and South Korea did not expand subscribers to the same extent as those in the US, but they were able to expand their market share in the UK and Germany while failing to increase it in the other three countries. Local OTT players, especially those in Europe and Asia, might need to be more strategic in coping with US-based firms' expansion by materializing the positive interaction effects among the three strategies to increase both their subscriber base and market share. • This paper analyzes the effects of three strategies on OTT platform performance: Pricing, M&As, and Content investments. • Pricing and Content investments are key factors affecting market share and subscribership in global OTT markets. • OTT-specialized firms not in the US did not expand subscribers to the same extent as those in the US. [ABSTRACT FROM AUTHOR]

This paper presents a human-centered approach for an efficient cucumber-harvesting robot system. Specifically, harvest ordering, visual servoing, and end-effector-based manipulation functionalities were integrated to realize efficient and stable harvesting. The proposed approach involved determining the optimal harvest ordering, guiding the end-effector to the cucumber pedicel through visual servoing, and designing an end-effector to effectively harvest long cucumbers. The performance of the system was evaluated through preliminary and field experiments. The results of the preliminary experiments showed that harvest ordering decreased the harvesting time and travel length and increased the battery efficiency. The visual servoing was robust, and pedicels could be rapidly detected at a speed of 16–23 FPS through computer vision technologies. The pedicel could be accurately positioned within the cutting area of the end-effector. Furthermore, the proposed end-effector could effectively cut thin cucumber pedicels (3–6 mm), with a 100.0% success rate. Field experiments were conducted at three sites in Korea: Green Monsters, Sangju smart-valley, and Fresh-farm. The harvest success rate at the three sites ranged from 50.9% to 60.0%, with an overall value of 56.6%. The overall average harvest time of 56.0 s. The positional accuracy of the system was within the optimal range of 0–30 mm. Furthermore, the primary causes of harvest failure were analyzed, and future research directions to improve the performance of harvest robots were discussed. [Display omitted] • The proposed human-centered approach can mimic human harvesting methods. • Optimizing the harvest order helps minimize the travel length and operation time. • The proposed system allows rapid detection and tracking of pedicel. • The proposed end-effector increases the success rate when cutting cucumber pedicels. • Preliminary and field experiments demonstrate the effectiveness of the system. [ABSTRACT FROM AUTHOR]

This paper examines the association between greenhouse gas (GHG) emissions, firm value and foreign ownership for Korean firms. In Korea, firms that emit GHG more than a given threshold have been mandated to disclose the levels of GHG emissions since 2011. We find that firms bound to disclose GHG emissions are likely to be valued less compared to firms without disclosure obligations. In addition, foreign investors' ownership is lower for mandatory-disclosure firms than firms without such requirements. Among mandatory-disclosure firms, GHG intensity is negatively associated with firm value and this association is strengthened after 2015, following the Paris Accords. • This study investigates greenhouse gas (GHG) emissions of Korean firms. • Firms required to disclose GHG emissions are valued less. • Foreign investors tend to avoid investing in Korean firms with heavy GHG emissions. • Firms are valued less as the GHG intensity increases, especially after 2015. [ABSTRACT FROM AUTHOR]

Under the rising pressure for low carbon energy transitions in Northeast Asia (NEA), interconnecting local power grids for interstate power trade allows to share reserve capacity and to redistribute intermittent renewable energy across time zones, contributing to regional sustainability. Using a linear programming model that minimizes total energy system costs to meet hourly power demand, we build a hypothetical electricity transmission model for three urban demand centers interconnecting China, South Korea, and Japan to test economic and environmental competitiveness of the trilateral power trade with carbon pricing. In the economic perspective our results indicate that interstate electricity trade enables cost savings at all levels of CO2 prices tested (0–180USD/ton of CO2 emitted) through more efficient fuel consumptions on an hourly basis at the NEA regional level. However, ambitious carbon pricing (above 90 USD/ton CO2 emitted) is still essential for trade to ensure equitable trade impacts for all participating nodes. While trade utilizes gaps in resource availabilities and technology costs across nodes in cost minimization, results show inadequate carbon pricing leads to extra thermal combustions at the local level although regional total emissions reduce. • This paper proposes a phased approach to Asia Supergrid by interconnecting the three demand centers of Northeast Asia, China North, South Korea, and Japan West, without remote renewable sources as a regional energy cooperation model to accelerate carbon phaseout. • The trilateral power trade is effective in reducing the total cost of energy system at all levels of CO2 prices tested (0–180USD/ton of CO2 emitted) compared to autarkic generation, but ambitious carbon pricing (above 90) is essential for ensuring low carbon transitions at all participating nodes. • Trade enables cost savings by increasing renewable power output in export nodesfor transmission and avoiding fuel/emission cost at import nodes. New investment cost for line construction and renewable expansion is offset. [ABSTRACT FROM AUTHOR]

This cross-sectional study investigated the impact of academic stress on first-/third-person shooter (F/TPS) game addiction and examined the potential mediating roles of depression and impulsivity in this relationship. Participants comprised 33,880 Korean adolescents identified from the Game Overuse General Survey. The present study examined the relationships between the variables via linear regression analysis and Hayes's (2013) PROCESS macro (Model 6). First, the linear regression analyses revealed that academic stress was positively and significantly associated with F/TPS game addiction (b = 0.24, SE = 0.01, p <.001). Second, simple mediation models suggested that the relationship between academic stress and F/TPS game addiction may be mediated by impulsivity (b =.11, Boot SE = 0.01, 95% Boot CI [0.11, 0.12]) and depression (b = 0.03, Boot SE = 0.01, 95% Boot CI [0.02, 0.03]). Moreover, the serial mediation model suggested that impulsivity and depression may serially mediate the relationship between academic stress and F/TPS game addiction (b =.02, SE = 0.01, 95% CI [0.02, 0.03]). A first alternative serial mediation model suggested that academic stress may be sequentially associated with depression and impulsivity, which may further lead to F/TPS game addiction (b = 0.06, SE = 0.01, 95% CI [0.05, 0.06]). These findings imply that academic stress, depression, and impulsivity could be potential risk factors for adolescent F/TPS game addiction. Finally, in this paper, we discuss the theoretical and practical implications of the study. • This study examines the association between academic stress and F/TPS game addiction. • Academic stress was indirectly associated with F/TPS game addiction via impulsivity. • Academic stress was indirectly associated with F/TPS game addiction through depression. • Results also suggested that impulsivity and depression may play serial mediation roles. [ABSTRACT FROM AUTHOR]

The potential impact of manganese mining on benthic remineralization in the Pacific Ocean was assessed in this study. We estimated total sediment oxygen uptake rates (TOU) using in situ autonomous benthic chambers at the polymetallic nodule and Co-rich polymetallic crust mining sites of Korea: at the Clarion-Clipperton Fracture Zone (PILOT site) in the eastern Pacific and the open-sea seamounts (OSM) 9-1 and OSM17 in the western Pacific, respectively. The TOU rates in the shallow seamount areas (0.58 ± 0.01–2.22 ± 0.04 mmol O 2 m−2 d−1) were significantly higher than in the PILOT station (0.21 ± 0.05 mmol O 2 m−2 d−1), indicating that relatively labile organic matter could be deposited according to the regional oceanographic features and water depth. The highest TOU found among the seamount areas was in the wide summit area at OSM9-1, which may be due to environmental conditions such as seasonal wind-driven mixing, upwelling around the seamount slope, and topography, which can increase productivity seasonally. Our findings suggest that organic carbon quality and hydrodynamics can be closely linked to benthic carbon mineralization in the targeted polymetallic mining areas of the Pacific. • We compared sediment oxygen uptake at two Pacific Ocean. • Sediment oxygen uptake was notably higher in shallow seamount areas. • Regional factors control the benthic oxidation of organic carbon. [ABSTRACT FROM AUTHOR]

Covid-19 has driven us abruptly to a new world of contactless society. It also compelled us to use online shopping, especially mobile shopping in South Korea, where the dominant mode of wireless communication was already 4G services when Covid-19 broke out. This paper examines the different roles of mobile networks and the Covid-19 pandemic in transforming mobile shopping submarkets in South Korea by estimating the long-term and short-term effects of these two factors on mobile shopping sales. We used a cointegration and an error correction model to estimate long-term and short-term effects separately. This paper finds that Covid-19 was a major short-term factor affecting sales in mobile shopping submarkets, while mobile network subscribers were a key long-term driving factor of mobile shopping sales growth. • We estimated the effects of mobile networks and Covid-19 on mobile shopping sales in South Korea. • Covid was a short-term factor affecting mobile shopping sales, while mobile network subscribers were a long-term driving factor. • This paper used a cointegration and an error correction model to estimate long-term and short-term effects separately. [ABSTRACT FROM AUTHOR]

• This paper presents the stress test method developed for Korean nuclear power plants focusing assessment method of plant response capability to the loss of safety functions due to extended loss of AC power (ELAP) and loss of ultimate heat sink (LUHS). • This paper also shows assessment results of plant response capability in the events of ELAP and LUHS of OPR1000 that is a standardized PWR by Korea based on the ABB-CE System 80. • Multi-barrier accident coping strategy (MACST) guidelines have been developed to accomplish specific tasks in support of emergency operating procedures (EOP) when the extended loss power AC power and/or loss of ultimate heat sink is in progress as a consequence of beyond design basis natural events. • Safety provisions to secure critical safety functions are presented with cliff edge time evaluation at each step of plant response to extended loss of AC power and loss of ultimate heat sink. This paper presents a stress test method developed for Korean nuclear power plant and assessment results of plant response capability of OPR1000 in an effort to enhance the safety against extreme natural events exceeding the design basis of the plant. Multi-barrier accident coping strategy (MACST) guidelines have been developed to accomplish specific tasks in support of Emergency Operating Procedures (EOP) when the Extended Loss of AC Power (ELAP) and/or Loss of Ultimate Heat Sink (LUHS) is in progress as a consequence of beyond design basis natural events. Provisions to secure critical safety functions are discussed with cliff edge time evaluation at each step of plant response to ELAP and LUHS. It is concluded that the plant can maintain the safe shutdown state through the natural circulation cooldown by steam generator and the electric power and can obtain additional capability and redundancy with off-site equipment to provide coping capability for an indefinite period. [ABSTRACT FROM AUTHOR]