• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.22 no.1
• /
• pp.143-160
• /
• 2023

It is important to secure the golden time of emergency vehicles for quick responses in disaster situations, such as fire, rescue, and first aid. This study proposes plans Emergency Vehicle Preemption (EVP) based on the analysis of emergency vehicle operation to secure the golden time of emergency vehicles and increase driving safety. The emergency vehicle dispatch statistics, emergency vehicle traffic accident statistics, and survey were used for the analysis. As a result of the analysis, the frequency of dispatch of emergency vehicles and traffic accidents are increasing gradually, but the rate of securing the golden time of emergency vehicles is approximately half, indicating that improvement measures are urgent. In the questionnaire survey, most citizens consent to the necessity of introducing EVP. In addition, the criteria for the range of emergency vehicles that could provide EVP and the allowable time for waiting were derived. These results could be used to prepare EVP operation strategies, and it is expected to contribute to improving emergency vehicle operation safety and increasing the golden time securing rate through a rapid expansion of EVP.

• Membrane Journal
• /
• v.33 no.2
• /
• pp.77-86
• /
• 2023

In this study, pore-filled ion exchange membranes with low membrane resistance and high hydroxide ion conductivity was developed. To improve alkali durability, a porous substrate made of polytetrafluoroethylene was used, and a copolymer was prepared using monomers 2-(dimethyl amino) ethyl methacrylate (DMAEMA) and vinyl benzyl chloride (VBC) for pores. divinyl benzene (DVB) was used as the cross-linker, and ion exchange membranes were prepared for each cross-linking agent content to study the effect of the cross-linker content on DMAEMA-DVB and VBC-DMAEMA-DVB copolymers. As a result, chemical stability is improved by using a PTFE material substrate, and productivity can be increased by enabling fast photo polymerization at a low temperature by using a low-pressure UV lamp. To confirm the physical and chemical stability of the ion exchange membrane required for an anion exchange membrane fuel cell, tensile strength, and alkali resistance tests were conducted. As a result, as the cross-linking degree increased, the tensile strength increased by approximately 40 MPa, and finally, through the silver conductivity and alkali resistance tests, it was confirmed that the alkaline stability increased as the cross-linking agent increased.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.5 no.5
• /
• pp.471-479
• /
• 2015

This study was conducted to make use of Korea Meteorological Administration(KMA)'s Automatic Weather Station(AWS) data to operate smart green greenhouse. A Web-based KMA AWS data receiving system using JAVA and APM_SETUP 8 on windows 7 platform was developed. The system was composed of server and client. The server program was developed by a Java application to receive weather data from the KMA every 30 minutes and to send the weather data to smart greenhouse. The client program was developed by a Java applets to receive the KMA AWS data from the server every 30 minutes through communicating with the server so that smart greenhouse could recognize the KMA AWS data as the ambient weather information. This system was evaluated by comparing with local weather data measured by Inc. Ezfarm. In case of ambient air temperature, it showed some difference between virtual data and measured data. But, the average absolute deviation of the difference has a little difference as less than 2.24℃. Therefore, the virtual weather data of the developed system was considered available as the ambient weather information of the smart greenhouse.

• Nutrition Research and Practice
• /
• v.17 no.4
• /
• pp.682-697
• /
• 2023

BACKGROUND/OBJECTIVES: Tibetan tea is a kind of dark tea, due to the inherent complexity of natural products, the chemical composition and beneficial effects of Tibetan tea are not fully understood. The objective of this study was to unravel the composition of Tibetan tea using knowledge-guided multilayer network (KGMN) techniques and explore its potential antioxidant and hypolipidemic mechanisms in mice. MATERIALS/METHODS: The C57BL/6J mice were continuously gavaged with Tibetan tea extract (T group), green tea extract (G group) and ddH2O (H group) for 15 days. The activity of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) in mice was detected. Transcriptome sequencing technology was used to investigate the molecular mechanisms underlying the antioxidant and lipid-lowering effects of Tibetan tea in mice. Furthermore, the expression levels of liver antioxidant and lipid metabolism related genes in various groups were detected by the real-time quantitative polymerase chain reaction (qPCR) method. RESULTS: The results showed that a total of 42 flavonoids are provisionally annotated in Tibetan tea using KGMN strategies. Tibetan tea significantly reduced body weight gain and increased T-AOC and SOD activities in mice compared with the H group. Based on the results of transcriptome and qPCR, it was confirmed that Tibetan tea could play a key role in antioxidant and lipid lowering by regulating oxidative stress and lipid metabolism related pathways such as insulin resistance, P53 signaling pathway, insulin signaling pathway, fatty acid elongation and fatty acid metabolism. CONCLUSIONS: This study was the first to use computational tools to deeply explore the composition of Tibetan tea and revealed its potential antioxidant and hypolipidemic mechanisms, and it provides new insights into the composition and bioactivity of Tibetan tea.

• Ecology and Resilient Infrastructure
• /
• v.10 no.4
• /
• pp.135-142
• /
• 2023

A various technology of remote sensing and image analysis are applied to study landscape changes and their influencing factors in stream corridors. We developed a method to detect landscape changes over time by calculating the optical index using multispectral images taken from satellites at various time points, calculating the threshold to delineate the boundaries of water bodies, and creating binarized maps into land and water areas. This method was applied to the upstream reach of the weirs in the Geumgang River to track changes in the sandbar formed by the opening of the weir gate. First, we collected multispectral images with a resolution of 10 m × 10 m taken from the Sentinel-2 satellite at various times before and after the opening of the dam in the Geumgang River. The normalized difference water index (NDWI) was calculated using the green light and near-infrared bands from the collected images. The Otsu's threshold of NDWI calculated to delineate the boundary of the water body ranged from -0.0573 to 0.1367. The boundary of the water area determined by remote sensing matched the boundary in the actual image. A map binarized into water and land areas was created using NDWI and the Otsu's threshold. According to these results of the developed method, it was estimated that a total of 379.7 ha of new sandbar was formed by opening the three weir floodgates from 2017 to 2021 in the longitudinal range from Baekje Weir to Daecheong Dam on the Geumgang River. The landscape detection method developed in this study is evaluated as a useful method that can obtain objective results with few resources over a wide spatial and temporal range.

• Journal of Marine Bioscience and Biotechnology
• /
• v.15 no.2
• /
• pp.41-48
• /
• 2023

The objective of the present study was to improve the biomass productivity of newly isolated freshwater green microalga Parachlorella sp. This was accomplished by culture conditions optimization, including CO₂ concentration, superficial gas velocity, and light intensity, in 0.5 L bubble column photobioreactors. The supplied CO₂ concentration and gas velocity varied from 0.032% (air) to 10% and 0.02 m/s - 0.11 m/s, respectively, to evaluate their effects on growth kinetics. Next, to maximize the production rate of Parachlorella sp., a lumostatic operation based on a specific light uptake rate (q_e) was applied. From these results, the optimal CO₂ concentration in the supplied gas and the gas velocity were determined to be 5% and 0.064 m/s, respectively. For the lumostatic operation at 10.2 µmol/g/s, biomass productivity and photon yield showed significant increases of 83% and 66%, respectively, relative to cultures under constant light intensity. These results indicate that the biomass productivity of Parachlorella sp. can be improved by optimizing gas properties and light control as cell concentrations vary over time.

• Korean Journal of Mineralogy and Petrology
• /
• v.36 no.4
• /
• pp.221-232
• /
• 2023

Carbon neutrality requires carbon dioxide reduction technology and alternative green energy sources. Palygorskite is a clay mineral with a ribbon structure and possess a large surface area due to the nanoscale pore size. The clay mineral has been proposed as a potential material to capture carbon dioxide (CO₂) and possibly to store eco-friendly hydrogen gas (H2). We report our preliminary results of grand canonical Monte Carlo (GCMC) simulations that investigated the adsorption isotherms and mechanisms of CO₂ and H₂ into palygorskite nanopores at room temperature. As the chemical potential of gas increased, the adsorbed amount of CO₂ or H₂ within the palygorskite nanopores increased. Compared to CO₂, injection of H₂ into palygorskite required higher energy. The mean squared displacement within palygorskite nanopores was much higher for H₂ than for CO₂, which is consistent with experiments. Our simulations found that CO₂ molecules were arranged in a row in the nanopores, while H₂ molecules showed highly disordered arrangement. This simulation method is promising for finding Earth materials suitable for CO₂ capture and H₂ storage and also expected to contribute to fundamental understanding of fluid-mineral interactions in the geological underground.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.26 no.4
• /
• pp.145-160
• /
• 2023

The purpose of this study was to compare and analyze diurnal thermal environments using Unmanned Aerial Vehicles(UAV)-derived physical parameters(NDVI, SVF) and ENVI-met modeling. The research findings revealed significant correlations, with a significance level of 1%, between UAV-derived NDVI, SVF, and thermal environment elements such as S↑, S↓, L↓, L↑, Land Surface Temperature(LST), and Tmrt. In particular, NDVI showed a strong negative correlation with S↑, reaching a minimum of -0.52^** at 12:00, and exhibited a positive correlation of 0.53^** or higher with L↓ at all times. A significant negative correlation of -0.61^** with LST was observed at 13:00, suggesting the high relevance of NDVI to long-wavelength radiation. Regarding SVF, the results showed a strong relationship with long-wave radiative flux, depending on the SVF range. These research findings offer an integrated approach to evaluating thermal comfort and microclimates in urban areas. Furthermore, they can be applied to understand the impact of urban design and landscape characteristics on pedestrian thermal comfort.

• Journal of Korean Society of Rural Planning
• /
• v.30 no.1
• /
• pp.33-42
• /
• 2024

The purpose of this study is to investigate the possible relationship between population migration and population inequality in rural areas. This study conducted a case study on the eup·myeon(rural)areas in Chungcheongbuk-do. First, the population migration was divided into four patterns, and the characteristics of population migration in rural areas were analyzed based on the net migration. The analysis results showed that there was serious migration between rural areas, and the population in rural areas mainly moved out to urban areas within the province, but the urban population outside the province moved out to rural areas. The main areas of population inflows included areas such as Deoksan-eup, Jincheon-gun, Osong-eup and Ochang-eup, Cheongju-si. Second, the Theil index was used to quantitatively analyze the level of population inequality between rural areas. The Theil index of the population aged 0~14 increased from 0.38 to 0.53, that of population aged 15-64 increased from 0.22 to 0.30, and that of population aged over 65 increased from 0.07 to 0.09, indicating an increase in population inequality. Finally, due to the continued large-scale inflows of population into Osong-eup and Ochang-eup, the Theil index of total population in Cheongju-si increased from 0.13 in 2009 to 0.23 in 2020, which meant that the level of population inequality had increased. Similarly, due to the continued large population inflows into Deoksan-eup, the Theil index of total population in Jincheon-gun increased from 0.14 in 2009 to 0.18 in 2020, which meant that the level of population inequality had increased. In conclusion, large-scale population inflows into specific areas will lead to an increase in the level of population inequality.

• Korean Chemical Engineering Research
• /
• v.62 no.1
• /
• pp.80-86
• /
• 2024

This study was conducted to evaluate the potential of rape stalk (RAS) as a raw material for the production of solid bio-fuels. RAS was immersed in an aqueous solution with acetic acid concentration of 1 percent, The content of reducing sugars separated from the RAS was analyzed. Glucose showed the highest content followed by xylose, galactose, arabinose and mannose. The immersed and non-immersed RAS were used for producing pellets with a pilot-scaled flat-die pellet mill. Bulk density and calorific values of the pellets improved with the use of the immersed RAS and the addition of wood particles. The values exceeded the minimum requirements for the A-grade of non-woody pellets (≧600 kg/m³ & ≧ 14.5 MJ/kg) designated by the ISO. Ash content of the pellets reduced with the immersion of RAS and the value satisfied the A-grade level (≦6.0%) of the ISO standard. The durability of the immersed RAS-based pellets was much higher than that of non-immersed IRS-based pellets, and the values were increased with the addition of wood particles. However, the durability did not meet the acceptance level for the B-grade of non-woody pellets (≧96.0%) designated by the ISO. These results suggested that the addition of binders in the production of non-woody pellets using an RAS immersed in acetic acid-based aqueous solution is required for the commercialization of the pellets.