• The Journal of Bigdata
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• v.8 no.2
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• pp.233-248
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• 2023

In the process of building the future of smart cities, innovation in mobility and road infrastructure is one of the most important topics. In particular, with the proliferation of autonomous vehicles and various types of mobility on the road, such as electric bicycles, electric kickboards, and electric wheels, roads have a variety of actors to accommodate, including traditional cars and pedestrians, and conflicts between them need to be resolved. Complete streets, a term coined in the United States in 2003, refers to the design and operation of roads that consider the equitable safety and convenience of all road users, including pedestrians, bicyclists, public transportation users, personal mobility (PM) users, and automobile drivers. Currently, many cities overseas are implementing complete streets, and research is being actively conducted to institutionalize them. However, there is a lack of research and discussion on complete streets in Korea. Therefore, this study aims to formalize the main factors to be considered in the design of complete streets by collecting and analyzing the opinions of academic and practitioner experts through the Delphi method. A total of three Delphi surveys were conducted, collecting free responses from experts through the first open-ended survey and organizing them into keywords to create the second and third closed-ended surveys. The second and third rounds of the survey consisted of a total of 52 questions, and 34 items out of 52 were selected as the final factors.

• Applied Chemistry for Engineering
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• v.35 no.4
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• pp.303-308
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• 2024

Currently, lithium secondary batteries have been used as medium- or large-sized energy sources such as electric vehicles and energy storage system (ESS) due to their high energy and eco-friendly characteristics. Currently commercialized lithium secondary batteries do not fully meet the demands for high energy density and safety. Many studies on solid electrolytes are being conducted to satisfy these requirements. In order to commercialize a solid electrolyte, it is important to supplement the low ion conductivity and high interface resistance with an electrode compared to the organic liquid electrolyte. Therefore, in this study, oligo(3,4-ethylenedioxythiophene (EDOT)) is added to poly(vinyl alcohol) (PVA), which is a polymer matrix with ion conductivity and sticky characteristics, to decrease the interfacial resistance with the same type of polythiophene (PTh)-based electrode. In addition, the addition of porous silicon dioxide (SiO₂) filler improves lithium salt dissociation ability and increases ionic conductivity. And the electrochemical stability of the solid electrolyte, which has been lowered due to additives, is improved by introducing a cross-linked structure using boric acid (BA).

• Journal of Wetlands Research
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• v.26 no.3
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• pp.245-253
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• 2024

Blue-green algal bloom, or harmful algal bloom has a negative impact on the aquatic ecosystem and purified water supply system due to oxygen depletion in the water body, odor, and secretion of toxic substances in the freshwater ecosystem. This Blue-green algal bloom is expected to increase in intensity and frequency due to the increase in algae's residence time in the water body after the construction of the Nakdong River weir, as well as the increase in surface temperature due to climate change. In this study, in order to respond to the expected increase in green algae phenomenon, an algal bloom forecast system based on hydro-meteorological factors was presented for preemptive response before issuing a algal bloom warning. Through polyserial correlation analysis, the preceding influence periods of temperature and discharge according to the algal bloom forecast level were derived. Using the decision tree classification, a machine learning technique, Classification models for the algal bloom forecast levels based on temperature and discharge of the preceding period were derived. And a algal bloom forecast system based on hydro-meteorological factors was derived based on the results of the decision tree classification models. The proposed algae forecast system based on hydro-meteorological factors can be used as basic research for preemptive response before blue-green algal blooms.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.4
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• pp.429-437
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• 2024

This study aimed to develop and commercialize abalone Haliotis discus hannai marinated in seasoned soy sauce (AM-S) for the elderly by adjusting its texture (hardness) and strengthening its nutritional components. The number of pounding cycles [X₁, 2-14 times] and heating time in a retort [X₂, 5-19 min] were selected as independent variables, and hardness (Y₁) and overall acceptance (Y₂) were selected as dependent variables. The optimal conditions for X₁ and X₂ were 12 pounding cycles and heating in a retort for 17 min, respectively. The hardness values 209.2×10³ N/m² for the third method and 259.1×10³ N/m² for the first method. The nutritional value was 13.1 g/100 g crude protein and vitamins A, D, and C were not detected. The mineral content was 33.2 mg/100 g calcium and 258.7 mg/100 g potassium. Organisms from the coliform group and Escherichia coli were not detected. Therefore, AM-S for the elderly was classified as a hardness- and nutrient-controlled product based on the standards and specifications of senior-friendly foods provided in the MFDS and classified as the first step of senior-friendly foods according to the standards and specifications of senior-friendly foods provided in the KS.

• Journal of the Society of Disaster Information
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• v.20 no.3
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• pp.573-583
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• 2024

Purpose: This study predicted the flow of chemical, biological, and radiological materials in chemical, biological, and radiological defense facilities within the base during a chemical, biological, and radiological attack based on the conditions of the facility before the existing improvement, analyzed the flow of pollutants and the human impact of toxic substances, and identified the occurrence of leakage. Method: Assuming that the simple chemical, biological, and radiological defense facility improvement plan, which reflects the characteristics of the building, has been improved to the facility standard, the flow of chemical, biological, and radiological materials in the chemical, biological, and radiological defense facility within the base was predicted in the event of a chemical, biological, and radiological attack under the same conditions, and the flow of contaminants and the impact on occupants by toxic substances were analyzed to determine spatial safety. Result: In the case of Plan 1, it was found that leakage occurred after approximately 250 seconds in spaces where existing flat-panel chemical, biological, and radiological defense facilities were not installed. In the cases of Plans 2 and 3, it was found that leakage occurred in spaces where existing flat-panel chemical, biological, and radiological defense facilities were not installed. Conclusion: n the case of plans 1, 2, and 3, it was found that airtightness was maintained because no leakage occurred in the improved plane. In the case of plan 4, airtightness was not maintained due to leakage in the space where the existing plane simple chemical, biological, and radiological protection facilities were not installed.

• Clean Technology
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• v.30 no.3
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• pp.175-187
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• 2024

Seaweeds are widely distributed along national coastlines around the world, and the biomass derived from them is an important marine biological organism. Seaweed is a crucial component of a healthy marine ecosystem. However, changes in marine environments have led to the occurrence of urchin barrens, and the damage caused by this phenomenon is steadily increasing. As a result, investigations into the distribution and spread of urchin barrens in the coastal areas of South Korea are being conducted regularly so efficient detection technologies are essential. One of the technologies that can swiftly and accurately analyze extensive areas is detection technology based on hyperspectral image information systems. This study aims to present the latest hyperspectral imaging technology for investigating the current status of urchin barrens and the methods for classifying this technology, including principles, preprocessing techniques, and correction methods. This study also proposes a classification technique for urchin barrens along the coast of Jeju Island that uses hyperspectral images and categorizes the urchin barrens into initial, intermediate, and advanced stages. The results showed that approximately 17.5% of the experimental areas were in the advanced stage. Based on this, various management and restoration methods tailored to different categories of urchin barren can be proposed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.50 no.3
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• pp.239-250
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• 2024

In this study, we investigated the skin safety, antioxidant, moisturizing, and anti-inflammatory effects of a composite extract of Prunus mume flower, Lonicera japonica flower, Chrysanthemum indicum flower, and Phyllostachys bambusoides (Royal TheraTea Guard^TM, RTG), which has been used as an internal medicine in the royal medical treatment for preventing skin damage caused by external environmental factors. In a cytotoxicity test on HaCaT cells, RTG complex extract showed no change in cell viability at concentrations of 0.125, 0.25, 0.5, and 1%, and a skin irritation index of 0.00 in a human patch test, confirming that it is non-irritating to the skin. The antioxidant effects was confirmed by the presence of 497.83 ㎍ GAE/g of polyphenols and increased DPPH radical scavenging activity, with a significant increase in catalase activity in the stratum corneum, showing potential as an antioxidant that protects cells from oxidative stress. The anti-inflammatory effects was observed through reduced erythema in skin stimulated by tape stripping and treated with fine dust in keratinocytes. The moisturizing effects was shown by increased expression of hyaluronan synthase (HAS)2, 3 and keratin1 in keratinocytes treated with fine dust compared to the control group, as well as increased skin moisture content and decreased skin roughness. These results suggest RTG can be used as a cosmetic ingredient to prevent skin damage caused by external environmental factors.

• The Journal of Engineering Geology
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• v.34 no.3
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• pp.459-471
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• 2024

Landslide risk is influenced by internal factors such as terrain, geology, soil composition, and forest cover, and external factors such as rainfall and seismic activity. In particular, changes in rainfall patterns due to climate change and changes in terrain due to urban sprawl result in increased landslide risk, both directly and indirectly. This study analyzes internal factors that influence landslide risk using existing spatial data and examines changes in rainfall under the SSP5-8.5 climate change scenario. Rainfall intensity was evaluated across different frequencies and durations, and the landslide risk was assessed by applying rainfall infiltration models to mountain slopes. The analysis reveals that with increasing rainfall duration (1, 6, 12, 18, and 24 h) for an event with a recurrence interval of 10 yr rainfall intensity decreases. However, for shorter rainfall durations (1 h), the intensity increases with the event frequency (10, 20, 50, and 100 yr). Infiltration analysis further shows that with prolonged rainfall, the proportion of areas with a safety factor of 1.3 or higher decreases, thereby raising the landslide risk.

• Journal of Korea Port Economic Association
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• v.40 no.3
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• pp.61-78
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• 2024

This study centered on labor demand between ship officers and ratings in the maritime sector, focusing on human capital theory. Ship officers bear the primary responsibilities in ship operations, including navigation, compliance with safety procedures, crew and resource management, and strategic decision-making, necessitating high levels of education and experience. Conversely, ratings execute various tasks aboard ships under the guidance of officers, contributing to daily operations. Using a multifactor Cobb-Douglas production function, the study evaluated the productivity of ship officers and ratings and analyzed the segmentation of their respective labor markets. The analysis revealed that globalization did not significantly impact either ship officers or ratings. However, technological advancements notably adversely affected the labor demand for ratings, highlighting its role in widening wage gaps and exacerbating job insecurity among less skilled workers within broader economic and social contexts. The study concludes by emphasizing the need for appropriate employment policies responsive to fluctuations in labor demand for ship officers and ratings due to economic changes. It also underscores the importance of flexible responses to the impacts of technological progress on different job sectors, advocating for policy approaches that prioritize worker education and training.

• Journal of the Korean Geotechnical Society
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• v.40 no.5
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• pp.77-92
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• 2024

This study investigates the impact of aluminum and water pollutants present in the effluent from wastewater treatment plants associated with agricultural and industrial facilities in the Geumgang waterway. The average aluminum concentration in the effluent from these facilities ranged from 0.19-3.14 mg/L. The R² values between the predicted and measured values at the confluence were 0.9237 and 0.9758, respectively, with an average aluminum concentration of 0.051 mg/L observed 10 km downstream. During the model calibration process, QUALKO2 outperformed QUAL2E, showing percent bias values of less than 11.9% and 18.9% for BOD and Chl-a, respectively. However, both models demonstrated similar performance in predicting T-N and T-P concentrations, as they both consider abiotic organic nitrogen and phosphorus. In conclusion, the impact of aluminum and water pollutants in the effluent from the Geumgang River agricultural and industrial complex wastewater treatment plant is relatively low. Nonetheless, for the safety of drinking water, continuous monitoring and proper maintenance of aluminum levels and water quality are essential.