• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4447-4464
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• 2023

This paper focuses on the development of a new computational model of the CNESTEN's TRIGA Mark II research reactor using the 3D continuous energy Monte-Carlo code TRIPOLI-4 (T4). This new model was developed to assess neutronic simulations and determine quantities of interest such as kinetic parameters of the reactor, control rods worth, power peaking factors and neutron flux distributions. This model is also a key tool used to accurately design new experiments in the TRIGA reactor, to analyze these experiments and to carry out sensitivity and uncertainty studies. The geometry and materials data, as part of the MCNP reference model, were used to build the T4 model. In this regard, the differences between the two models are mainly due to mathematical approaches of both codes. Indeed, the study presented in this article is divided into two parts: the first part deals with the development and the validation of the T4 model. The results obtained with the T4 model were compared to the existing MCNP reference model and to the experimental results from the Final Safety Analysis Report (FSAR). Different core configurations were investigated via simulations to test the computational model reliability in predicting the physical parameters of the reactor. As a fairly good agreement among the results was deduced, it seems reasonable to assume that the T4 model can accurately reproduce the MCNP calculated values. The second part of this study is devoted to the sensitivity and uncertainty (S/U) studies that were carried out to quantify the nuclear data uncertainty in the multiplication factor k_eff. For that purpose, the T4 model was used to calculate the sensitivity profiles of the k_eff to the nuclear data. The integrated-sensitivities were compared to the results obtained from the previous works that were carried out with MCNP and SCALE-6.2 simulation tools and differences of less than 5% were obtained for most of these quantities except for the C-graphite sensitivities. Moreover, the nuclear data uncertainties in the k_eff were derived using the COMAC-V2.1 covariance matrices library and the calculated sensitivities. The results have shown that the total nuclear data uncertainty in the k_eff is around 585 pcm using the COMAC-V2.1. This study also demonstrates that the contribution of zirconium isotopes to the nuclear data uncertainty in the k_eff is not negligible and should be taken into account when performing S/U analysis.

• Journal of the Korean Association of Geographic Information Studies
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• v.27 no.1
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• pp.12-28
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• 2024

This study aims to identify the trend of changes in tourist floating population before and after COVID-19 in major tourist destinations in Jeju Island through spatial analysis. Seongsan-eup and Andeok-myeon in Jeju Island were selected as the research area, and the research period was set at 1 year before and 2 years after the COVID-19 outbreak. For the analysis, mobile floating population data was refined and processed to calculate floating population distribution and floating population increase/decrease data. This was converted into spatial data and an overlay analysis was performed with location data of major tourist attractions. As a result of the analysis, it was confirmed that the floating population of indoor tourist attractions and small facilities decreased immediately after COVID-19, and that in open coastal areas or large facilities, the floating population decreased less or actually increased. In conclusion, in tourism development, it is necessary to identify changes in floating population according to the characteristics of tourist facilities, and it is necessary to develop tourism facilities and strategies that can respond to risk situations such as pandemics when developing tourist destinations.

• Journal of the Korean earth science society
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• v.45 no.3
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• pp.173-191
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• 2024

Typhoons are significant meteorological phenomena that cause interactions among the ocean, atmosphere, and land within Earth's system. In particular, wind speed, a key characteristic of typhoons, is influenced by various factors such as central pressure, trajectory, and sea surface temperature. Therefore, a comprehensive understanding based on actual observational data is essential. In the 2015 revised secondary school textbooks, typhoon wind speed is presented through text and illustrations; hence, exploratory activities that promote a deeper understanding of wind speed are necessary. In this study, we developed a data visualization program with a graphical user interface (GUI) to facilitate the understanding of typhoon wind speeds with simple operations during the teaching-learning process. The program utilizes red-green-blue (RGB) image data of Typhoons Mawar, Guchol, and Bolaven -which occurred in 2023- from the Korean geostationary satellite GEO-KOMPSAT-2A (GK-2A) as the input data. The program is designed to calculate typhoon wind speeds by inputting cloud movement coordinates around the typhoon and visualizes the wind speed distribution by inputting parameters such as central pressure, storm radius, and maximum wind speed. The GUI-based program developed in this study can be applied to typhoons observed by GK-2A without errors and enables scientific exploration based on actual observations beyond the limitations of textbooks. This allows students and teachers to collect, process, analyze, and visualize real observational data without needing a paid program or professional coding knowledge. This approach is expected to foster digital literacy, an essential competency for the future.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.23 no.3
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• pp.1-16
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• 2024

In the present highway design guidelines suggest that the capacity of one-lane hi-pass lanes is 2,000 veh/h for mainline toll plaza and 1,700 veh/h for interchange toll plaza. However, in a study conducted in early 2010, capacity of the mainline toll plaza was presented with 1,476 veh/h/ln to 1,665 veh/h/ln, and capacity of the interchange toll plaza was presented as 1,443 veh/h/ln. Accordingly, this study examined the feasibility of the capacity of the currently proposed highway one-lane hi-pass lane. Based on the 2021 individual vehicle passing data collected from the one-lane hi-pass gantry, the speed-traffic volume relationship graph and headway were used to calculate and compare capacity. In addition, the bootstrapping technique was introduced to utilize the headway and new processing methods for collected data were reviewed. As a result of the analysis, the one-lane hi-pass capacity could be estimated at 1,700 veh/h/ln for the interchange toll plaza, and at least 1,700 veh/h/ln for the mainline toll plaza. In addition, by using the bootstrap technique when using headway data, it was possible to present an estimated capacity similar to the observed capacity.

• Journal of Gastric Cancer
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• v.24 no.3
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• pp.341-352
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• 2024

Purpose: Textbook outcome is a comprehensive measure used to assess surgical quality and is increasingly being recognized as a valuable evaluation tool. Delta-shaped anastomosis (DA), an intracorporeal gastroduodenostomy, is a viable option for minimally invasive distal gastrectomy in patients with gastric cancer. This study aims to evaluate the surgical outcomes and calculate the textbook outcome of DA. Materials and Methods: In this retrospective study, the records of 4,902 patients who underwent minimally invasive distal gastrectomy for DA between 2009 and 2020 were reviewed. The data were categorized into three phases to analyze the trends over time. Surgical outcomes, including the operation time, length of post-operative hospital stay, and complication rates, were assessed, and the textbook outcome was calculated. Results: Among 4,505 patients, the textbook outcome is achieved in 3,736 (82.9%). Post-operative complications affect the textbook outcome the most significantly (91.9%). The highest textbook outcome is achieved in phase 2 (85.0%), which surpasses the rates of in phase 1 (81.7%) and phase 3 (82.3%). The post-operative complication rate within 30 d after surgery is 8.7%, and the rate of major complications exceeding the Clavien-Dindo classification grade 3 is 2.4%. Conclusions: Based on the outcomes of a large dataset, DA can be considered safe and feasible for gastric cancer.

• Journal of Animal Science and Technology
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• v.66 no.3
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• pp.504-513
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• 2024

Duck meat is recognized as a healthier poultry product that contains higher amounts of unsaturated and essential fatty acids, iron, and excellent amounts of protein. It has been found to possess the ability to reduce low-density lipoprotein cholesterol and subsequently, blood pressure in the human body; and improve the immunity system. The current study investigated the appropriate bedding depths of rice hulls as a preferred bedding material by evaluating the growth performance and carcass traits of White Pekin ducks raised for 42 days. A total of 288 one-day-old White Pekin ducklings were randomly allotted to floor cages with one of four bedding depths at 4 cm, 8 cm, 12 cm, and 16 cm. Ducklings were fed standard duck starter (days 1-21) and finisher (days 22-42) diets. The birds were stocked at a rate of 6 birds/m² with 6 replicates per treatment. Growth performance evaluation for the body weight, average daily gain, and average daily feed intake were measured to calculate the weekly feed conversion ratio. Breast, leg, and carcass yield were assessed as carcass traits. The muscle color and proximate composition were also analyzed for meat quality. Footpad dermatitis was also evaluated on day 42. Ducks reared on 16 cm bedding depth over the 42 days recorded higher (p < 0.05) body weight, average daily, average daily feed intake, and improved feed conversion ratios compared to other groups. The crude fat in breast meat also lowered (p < 0.05) in ducks reared at 16 cm (1.02%) when compared to ducks raised at 4 cm bedding depth (2.11%). Our results showed improved redness (p < 0.05) when the depth of bedding materials was elevated. Except for the breast meat fat, the dissimilar bedding depths did not affect (p < 0.05) the breast and leg meat composition, footpad dermatitis, and mortality for the current study. In conclusion, this study indicated that the bedding depths would directly or indirectly affect the growth performance and meat color of White Pekin ducks; and the bedding depth of rice hulls at 16 cm improved the growth performance of White Pekin ducks for 42 days.

• Land and Housing Review
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• v.15 no.3
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• pp.141-151
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• 2024

This paper presents the results of an experimental study to evaluate the shear behavior of reinforced concrete beams reinforced with FRCM composites using different types of textile grids. It was found that the shear behavior of reinforced concrete beams with FRCM composites was observed by comparing the strains measured in the stirrups and textile grids. It was found that the ultimate strength of the strengthened specimens increased compared to the basic specimens, and the failure mode at ultimate strength changed from shear failure to bending failure. When the shear strength design values of the KDS 14 20 22 and AIJ ultimate strength types were compared with the actual experimental values, it was found that the AIJ ultimate strength type was more accurate. In addition, the shear contribution of FRCM composites in the A and T models was compared, and the results showed that both models had similar trends. Reflecting these results, it is recommended that further studies should be conducted to calculate the shear performance of beam members with FRCM composites and the shear contribution of FRCM composites by using the stirrup reinforcement ratio and the type of textile grid as variables.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.4
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• pp.577-585
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• 2024

Infrastructure plays a crucial role in the industrial development and economic growth of a nation. However, recently, domestic infrastructure has been causing not only safety risks due to aging but also social and economic inefficiencies, increasing the need for maintenance. In particular, the deterioration rate of bridges is serious, so application of appropriate repair and rehabilitation methods and estimation of its quantity are required. In this study, frequently applied repair methods for bridges using data from the Facility Integrated Management System (FMS) were identified. the empirical correlation between damage volume and the repair volume was analyzed using Bridge Management System (BMS) data. The result of the analysis showed that the ratio of the repair volume to the damage volume was 1.0. The guideline, on the other hand, suggest 1.5 the ratio of the repair volume to the damage volume. Although the guidelines differently present more conservative figures considering safety, this study is significant in that it presents a practical ratio through data analysis results. This results can be used to develop a model that can calculate the amount of repair and rehabilitation of various facilities in the future.

• Journal of the Society of Naval Architects of Korea
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• v.61 no.4
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• pp.267-277
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• 2024

The Sortie Generation Rate (SGR) is a critical performance indicator for carrier-based aircraft and is a key factor for the carrier design process. This study aims to analyze the factors that affect SGR and establish a representative Sortie Generation Process (SGP) along with simulation results to calculate SGR for a naval ship equipped to carry aircraft. Detailed SGR factors are identified from the perspectives of the aircraft, aviation personnel, and aircraft carrier during the flight preparation stage, and the SGP is established accordingly. As a representative, Korean Navy's CVX basic design is chosen for detailed analysis. The physical dimension and spots for the deck design with time and probabilistic data of SGP are considered to develop a queueing network model for SGR calculation. To consider the specific probabilistic features, the model was solved with discrete event simulation tools(SimPy and AnyLogic) where the results show great agreement. Such findings on SGR factors and calculation are expected to be incorporated in the future development of SGR calculation algorithms and also present guidelines for proper design of aircraft carrier based on concrete operation concept.

• Journal of Industrial Convergence
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• v.22 no.7
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• pp.1-13
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• 2024

Among e-government services, the intelligent CCTV control platform is a screening control service that utilizes artificial intelligence to display major objects such as people, cars, etc. to control personnel when they appear on CCTV. The operation of an intelligent CCTV control platform is expected to improve the quality of life of citizens by enabling rapid response in the event of an emergency and increasing the resolution of complaints. In this study, the benefits of the intelligent CCTV control platform, a non-market good, were estimated by applying the contingent valuation method (CVM), a choice experiment technique, to estimate the average willingness to pay per household and calculate the social benefits. As a result of the analysis, the average willingness to pay per household was estimated to be KRW 6,908 per year, and the economic benefits for the country as a whole were estimated to be about KRW 150.4 billion per year. This study is of academic significance as it extends the application of CVM to the field of intelligent e-Government services. The Intelligent CCTV control platforms is being actively discussed, this study has practical implications in that the benefits were estimated in monetary value.