• Journal of the Korean Regional Science Association
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• v.40 no.2
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• pp.107-130
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• 2024

Urban land surface temperature (LST) change is a major environmental factor that affects the thermal comfort, energy consumption, and health of urban residents. Most studies that explored the relationship between LST and urban built-environment form analyzed only midday LST. This study explores the diurnal variation of summertime LST in Seoul using ECOSTRESS data, which observes LST at various times of the day and analyzes whether the LST variation differs by built environment type. Launched in 2018, ECOSTRESS operates in a non-sun-synchronous orbit, observing LST with a high resolution of 70 meters. This study collected data from early morning (6:25) to evening (17:26) from 2019 to 2022 to build time-series LST. Based on greenery, water bodies, and building form data, eight types of Seoul's built environment were derived by hierarchical clustering, and the LST fluctuation characteristics of each cluster were compared. The results showed that the spatial disparity in LST increased after dawn, peaked at noon, and decreased again, highlighting areas with rapid versus stable LST changes. Low-rise and high-rise compact districts experienced fast, high temperature increases and high variability, while low-density apartments experienced moderate LST increases and low variability. These results suggest urban forms that can mitigate rapid daytime heating.

• Land and Housing Review
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• v.15 no.2
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• pp.107-124
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• 2024

Based on Muan-gun, Jeollanam-do, this study explores how to mitigate the disappearance of rual areas. The study surveyed 95 young farmers in Muan-gun to assess their farming practices and the challenges they face. We further employ factor analysis and cluster analysis classify young farmers in Muan-gun, facilitating the identification of tailored policies or initiatives aimed at fostering and supporting young farmers. The results are summarized as follows. First, Muan County does not have any ordinances or original projects specifically designed to support young farmers. Second, the succession rate of farmland among young farmers in Muan County is 41.1%, which is comparable to the national rate of 43.7%. This indicates that approximately 40% of young farmers in Korea have inherited farmland, a critical foundation for agricultural activities. Third, despite accumulating farming experience, young farmers have not seen any improvement in local living conditions, and rather their difficulties have intensified. Fourth, this study conducted a factor analysis using 21 variables, resulting in the selection of seven common factors for cluster analysis. Consequently, young farmers in Muan County were categorized into three groups. The multinomial logit analysis revealed that the typology of young farmers is influenced by indicators such as cultivated area, farming experience, demand for smart farms, farm income, and farming type (rice cultivation or other). Therefore, to attract young farmers and prevent the decline of rural areas, policy efforts should focus on minimizing entry barriers to farming infrastructure, such as access to farmland, and improving local settlement conditions.

• Journal of the Korea Society of Computer and Information
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• v.29 no.4
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• pp.145-153
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• 2024

Through the 106th session of the International Maritime Organization(IMO)'s Maritime Safety Committee(MSC), a mandatory safety training requirement for all personnel transferred or accommodated for offshore industrial activities was established and adopted under the name of SOLAS Chapter XV, IP(Industrial Personnel) Code. This regulation mandates pre-boarding safety training to enable individuals to anticipate and mitigate hazardous risks in navigation and operational environments. Consequently, the IP Code includes provisions regarding the training content for industrial personnel and regulations for the refusal of master who has a full responsibility for individuals who have not completed the required training(non-qualified industrial personnel). Referred to as the IP Code, this agreement is set to enter into force in July 2024, necessitating the establishment and operation of safety education for industrial personnel boarding ships before that date. Accordingly, this paper reviews the legal requirements related to training within IP code and analyzes the details of models including training objectives, target audience, duration, and course structure of safety trainings such as STCW, OPITO, GWO training, and other delegated training related to current ships. Additionally, it aims to propose a curriculum model for IP training courses which consists of a total of 16 hours over 2 days, offered by the Korea Institute of Maritime and Fisheries Technology, including teaching objectives, duration, and course structure.

• Journal of Korea Water Resources Association
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• v.57 no.5
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• pp.311-320
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• 2024

Climate change has been intensifying drought frequency and severity. Such prolonged droughts reduce reservoir levels, thereby exacerbating drought impacts. While previous studies have focused on optimizing reservoir operations using historical data to mitigate these impacts, their scope is limited to analyzing past events, highlighting the need for predictive methods for future droughts. This research introduces a novel approach for predicting minimum inflow at the Seomjingang dam which has experienced significant droughts. This study utilized the Stochastic Analysis Modeling and Simulation (SAMS) 2007 to generate inflow sequences for the same period of observed inflow. Then we simulate reservoir operations to assess firm yield and predict minimum inflow through synthetic inflow analysis. Minimum inflow is defined as the inflow where firm yield is less than 95% of the synthetic inflow in many sequences during periods matching observed inflow. The results for each case indicated the firm yield for the minimum inflow is on average 9.44 m³/s, approximately 1.07 m³/s lower than the observed inflow's firm yield of 10.51 m³/s. The minimum inflow estimation can inform reservoir operation standards, facilitate multi-reservoir system reviews, and assess supplementary capabilities. Estimating minimum inflow emerges as an effective strategy for enhancing water supply reliability and mitigating shortages.

• Journal of the Korean GEO-environmental Society
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• v.25 no.6
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• pp.19-24
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• 2024

Urban densification has necessitated the development of subterranean spaces such as subway networks and underground tunnels to facilitate the dispersal and movement of populations. Development of these underground spaces requires excavation from the ground surface, which can induce groundwater flow and potentially lead to ground subsidence and sinkholes, damaging structures. To mitigate these risks, it is essential to model groundwater flow prior to construction, analyze its characteristics, and predict potential groundwater discharge during excavation. In this study, we collected meteorological, topographical, and soil conditions data for the city of ○○, where tunnel construction was planned. Using the Visual MODFLOW program, we modeled the groundwater flow. Excavation sections were set as drainage points to monitor groundwater discharge during the excavation process, and the effectiveness of seepage control measures was assessed. The model was validated by comparing measured groundwater levels with those predicted by the model, yielding a coefficient of determination of 0.87. Our findings indicate that groundwater discharge is most significant at the beginning of the excavation. Additionally, the presence of seepage barriers was found to reduce groundwater discharge by approximately 59%.

• Korean Journal of Poultry Science
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• v.51 no.2
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• pp.73-82
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• 2024

The gut microbiome of broilers is a critical factor in overall health and productivity. However, high summer temperatures and high stocking density (conventional farm condition) may cause stress to broilers, resulting in an imbalance in the gut microbiome. This study was conducted to compare the gut microbiome of broilers between spring and summer in welfare (Bosung, Jeollanam-do, South Korea) and conventional farms (Jangsu, Jeollabuk-do, South Korea). A total of 31 broilers were assigned to the following groups: conventional farm in spring (n = 8); conventional farm in summer (n = 8); welfare farm in spring (n = 7); welfare farm in summer (n = 8). Cecal digesta were collected from eight broilers from each farm, and microbiome analysis was performed using 16S rRNA gene sequencing. Beta diversity analysis indicated clear differences in cecal microbiome composition between spring and summerin both welfare and conventional farm. At the phylum level, analysis of conventional farm revealed a higher proportion of Bacteroidetes in spring than in summer. At the genus level, broilers exhibited a higher abundance of Bacteroides and Alistipesin spring compared to summer. In contrast, the difference in microbial flora composition observed in welfare farm was relatively small compared to conventional farm. In conclusion, the results of this study suggest that heat stress can negatively affect the caecum microbiome of broilers. However, improvements in the housing environment can mitigate the effects of heat stress.

• Journal of Korea Water Resources Association
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• v.57 no.6
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• pp.409-419
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• 2024

Climate change is already impacting sustainable water resource management. The influence of climate change on water supply from reservoirs has been generally assessed using climate change scenarios generated based on global climate models. However, inherent uncertainties exist due to the limitations of estimating climate change by assuming IPCC carbon emission scenarios. The decision scaling approach was applied to mitigate these issues in this study focusing on four reservoir watersheds: Chungju, Yongdam, Hapcheon, and Seomjingang reservoirs. The reservoir water supply reliablity was analyzed by combining the rainfall-runoff model (IHACRES) and the reservoir operation model based on HEC-ResSim. Water supply reliability analysis was aimed at ensuring the stable operation of dams, and its results ccould be utilized to develop either structural or non-structural water supply plans. Therefore, in this study, we aimed to assess potential risks that might arise during the operation of reserviors under various climate conditions. Using observed precipitation and temperature from 1995 to 2014, 49 climate stress scenarios were developed (7 precipitation scenarios based on quantiles and 7 temperature scenarios ranging from 0℃ to 6℃ at 1℃ intervals). Our study demonstrated that despite an increase in flood season precipitation leading to an increase in reservoir discharge, it had a greater impact on sustainable water management compared to the increase in non-flood season precipitation. Furthermore, in scenarios combining rainfall and temperature, the reliability of reservoir water supply showed greater variations than the sum of individual reliability changes in rainfall and temperature scenarios. This difference was attributed to the opposing effects of decreased and increased precipitation, each causing limitations in water and energy-limited evapotranspiration. These results were expected to enhance the efficiency of reservoir operation.

• Journal of Ginseng Culture
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• v.6
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• pp.51-79
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• 2024

In the 1970s and 1980s, during the nascent phase of ginseng disease research, efforts concentrated on isolating and identifying pathogens. Subsequently, their physiological ecology and pathogenesis characteristics were scrutinized. This led to the establishment of a comprehensive control approach for safeguarding major aerial part diseases like Alternaria blight, anthracnose, and Phytophthora blight, along with underground part diseases such as Rhizoctonia seedling damping-off, Pythium seedling damping-off, and Sclerotinia white rot. In the 1980s, the sunshade was changed from traditional rice straw to polyethylene (PE) net. From 1987 to 1989, focused research aimed at enhancing disease control methods. Notably, the introduction of a four-layer woven P.E. light-shading net minimized rainwater leakage, curbing Alternaria blight occurrence. Since 1990, identification of the bacterial soft stem rot pathogen facilitated the establishment of a flower stem removal method to mitigate outbreaks. Concurrently, efforts were directed towards identifying root rot pathogens causing continuous crop failure, employing soil fumigation and filling methods for sustainable crop land use. In 2000, adapting to rapid climate changes became imperative, prompting modifications and supplements to control methods. New approaches were devised, including a crop protection agent method for Alternaria stem blight triggered by excessive rainfall during sprouting and a control method for gray mold disease. A comprehensive plan to enhance control methods for Rhizoctonia seedling damping-off and Rhizoctonia damping-off was also devised. Over the past 50 years, the initial emphasis was on understanding the causes and control of ginseng diseases, followed by refining established control methods. Drawing on these findings, future ginseng cultivation and disease control methods should be innovatively developed to proactively address evolving factors such as climate fluctuations, diminishing cultivation areas, escalating labor costs, and heightened consumer safety awareness.

• Journal of Korea Water Resources Association
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• v.57 no.3
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• pp.209-223
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• 2024

In the context of the fourth industrial revolution, data-driven decision-making has increasingly become pivotal. However, the integrity of data analysis is compromised if data quality is not adequately ensured, potentially leading to biased interpretations. This is particularly critical for water level data, essential for water resource management, which often encounters quality issues such as missing values, spikes, and noise. This study addresses the challenge of noise-induced data quality deterioration, which complicates trend analysis and may produce anomalous outliers. To mitigate this issue, we propose a noise removal strategy employing Wavelet Transform, a technique renowned for its efficacy in signal processing and noise elimination. The advantage of Wavelet Transform lies in its operational efficiency - it reduces both time and costs as it obviates the need for acquiring the true values of collected data. This study conducted a comparative performance evaluation between our Wavelet Transform-based approach and the Denoising Autoencoder, a prominent machine learning method for noise reduction.. The findings demonstrate that the Coiflets wavelet function outperforms the Denoising Autoencoder across various metrics, including Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and Mean Squared Error (MSE). The superiority of the Coiflets function suggests that selecting an appropriate wavelet function tailored to the specific application environment can effectively address data quality issues caused by noise. This study underscores the potential of Wavelet Transform as a robust tool for enhancing the quality of water level data, thereby contributing to the reliability of water resource management decisions.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.39-45
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• 2023

Biorenovation is a biotransformation method that converts the structure of chemical compounds and natural product through biocatalytic metabolism of microorganism and could enhance biological effectiveness and mitigate cytotoxicity compared to its substrates. Althaea rosea L. has been used as oriental medicine and is known for physiological efficacies such as antiurolithiatic, anti-inflammatory, and anti-cancer activities. A. rosea L. callus, the plant tissue grown to protect its wound, has been reported to have antioxidant and whitening effects. However, mechanisms of its other activity such as inflammation have not yet been investigated. In this study, we extracted A. rosea L. callus (AR) and produced biorenovated AR (ARBR), and then analyzed anti-inflammatory effect in Lipopolysaccharide-induced RAW 264.7 macrophage at 50, 100, 200 ㎍/mL of ARBR. As a result of inhibition test of nitric oxide production, it was found that ARBR was superior to AR without apparent toxicity. Furthermore, ARBR significantly inhibited production of prostaglandin E₂, inducible nitric oxide synthase, cyclooxygenase-2 and pro-inflammatory cytokines including Tumor necrosis factor-α, Interleukin-6, Interleukin-1β in a concentration-dependent manner. In conclusion, we suggest that ARBR could regulate the excessive inflammatory response to an appropriate level and be a promising material for functional cosmetics and pharmaceuticals.