• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.953-966
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• 2023

As the importance of renewable energy diffusion spreads, promotion of sustainable renewable energy projects such as agrivoltaics is expected to accelerate. Furthermore, to promote agrivoltaics projects, it must be considered the legislation related to agrivoltaics and Chungnam Province's local policy. This research focuses on the selection of the most suitable sites for agrivoltaics installations in Chungnam Province in South Korea. Therefore, the process of this research was as follows. First, the legislation related to agrivoltaics and local policy in Chungnam Province were identified. Second, it employs an analytic hierarchy process (AHP) to consider important criteria and their weights for site selection. Third, based on the weights calculated AHP, geographic information system (GIS) was performed to select most suitable location selection of agrivoltaics installations in Chungnam Province. The analysis identified approximately 60 promising most suitable location for agrivoltaics installations in Chungnam Province, primarily in the northern part of Chungnam Province. These areas are expected to meet electricity demands in nearby regions since these are relatively adjacent to Gyeonggi Province. According to the results of research, policy suggestions related to agrivoltaics were presented separately into the agricultural sector and the electricity power sector. The study's results serve as a valuable resource for future national-level candidate site selection for agrivoltaics projects.

• New & Renewable Energy
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• v.20 no.1
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• pp.88-94
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• 2024

This study explored the potential and implementation of renewable energy sources in Sri Lanka, focusing on the theoretical potential of solar and wind energy to develop self-reliant energy models. Using advanced climate data from the European Centre for Medium-Range Weather Forecasts and Global Solar/Wind Atlas provided by the World Bank, we assessed the renewable energy potential across Sri Lanka. This study proposes off-grid and minigrid systems as viable solutions for addressing energy poverty in rural regions. Rural villages were classified based on solar and wind resources, via which we proposed four distinct energy self-reliance models: Renewable-Dominant, Solar-Dominant, Wind-Dominant, and Diesel-Dominant. This study evaluates the economic viability of these models considering Sri Lanka's current energy market and technological environment. The outcomes highlight the necessity for employing diversified energy strategies to enhance the efficiency of the national power supply system and maximize the utilization of renewable resources, contributing to Sri Lanka's sustainable development and energy security.

• International Journal of Computer Science & Network Security
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• v.24 no.7
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• pp.11-23
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• 2024

Triage is a practice of accurately prioritizing patients in emergency department (ED) based on their medical condition to provide them with proper treatment service. The variation in triage assessment among medical staff can cause mis-triage which affect the patients negatively. Developing ED triage system based on machine learning (ML) techniques can lead to accurate and efficient triage outcomes. This study aspires to develop a triage system using machine learning techniques to predict ED triage levels using patients' information. We conducted a retrospective study using Security Forces Hospital ED data, from 2021 through 2023 during Hajj period in Saudia Arabi. Using demographics, vital signs, and chief complaints as predictors, two machine learning models were investigated, naming gradient boosted decision tree (XGB) and deep neural network (DNN). The models were trained to predict ED triage levels and their predictive performance was evaluated using area under the receiver operating characteristic curve (AUC) and confusion matrix. A total of 11,584 ED visits were collected and used in this study. XGB and DNN models exhibit high abilities in the predicting performance with AUC-ROC scores 0.85 and 0.82, respectively. Compared to the traditional approach, our proposed system demonstrated better performance and can be implemented in real-world clinical settings. Utilizing ML applications can power the triage decision-making, clinical care, and resource utilization.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.8
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• pp.2281-2297
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• 2024

Employing multiple drones as a swarm to complete missions can sharply improve the working efficiency and expand the scope of investigation. Remote UAV swarms utilize satellites as relays to forward investigation information. The increasing amount of data demands higher transmission rate and complex field network coding (CFNC) is deemed as an effective solution for data return. CFNC applied to UAV swarms enhances transmission efficiency by occupying only two time slots, which is less than other network coding schemes. However, conventional CFNC applied to UAVs is combined with constant coding and modulation scheme and results in a waste of spectrum resource when the channel conditions are better. In order to avoid the waste of power resources of the relay satellite and further improve spectral efficiency, a CFNC transmission scheme with MPSK modulation is proposed in this paper. For the proposed scheme, the satellite relay no longer directly forwards information, but transmits information after processing according to the current channel state. The proposed transmission scheme not only maintains throughput advantage of CFNC, but also enhances spectral efficiency, which obtains higher throughput performance. The symbol error probability (SEP) and throughput results corroborated by Monte Carlo simulation show that the proposed transmission scheme improves spectral efficiency in multiples compared to the conventional CFNC schemes. In addition, the proposed transmission scheme enhances the throughput performance for different topology structures while keeping SEP below a certain value.

• Journal of Food Hygiene and Safety
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• v.34 no.4
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• pp.404-411
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• 2019

This study was carried out to investigate the antioxidant effects of extracts from 9 species of forest plants in Korea. DPPH, ABTS, $NaNO_2$, hydrogen peroxide radical scavenging activity and reducing power activity were evaluated to measure the antioxidant activities of plant extracts. As a result, Geranium thunbergii has been identified as the most effective antioxidant resource. Also, total phenolic content was highest in Geranium thunbergii ($303.94{\pm}0.63mg\;GAE/g$) among 9 species extracts. Total flavonoid content was highest in Rosa multiflora ($24.32{\pm}0.22mg\;QE/g$) and proanthocyanidin content was highest in Vitis ficifolia ($279.00{\pm}4.58mg\;CE/g$) among 9 species extracts. In addition, the protective effect of plant extracts in $H_2O_2-induced$ human dermal fibroblast (HDF) cell systems were also assessed. Significant protective effects in $H_2O_2-induced$ human dermal fibroblast (HDF) cell systems were found in all plant extracts, especially in Geranium thunbergii. These results suggest that Geranium thunbergii could be a potential natural resource for antioxidant activity.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.243-254
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• 2019

With the recent accelerated policy-making and interests in new renewable energy, plans to develop and supply the new renewable energy have been devised across multiple regions in Korea. Solar energy, in particular, is being applied to small-scale power supply in provincial areas, as solar cells are used to convert solar energy into electric energy to produce electric power. Nonetheless, in the case of solar power plants, the need for a large stretch of land and considerable sum of financial support implies that the planning step should take into consideration the most suitable meteorological and geographical factors. In this study, the proxy variables of meteorological and geographical factors associated with solar energy were considered in analyzing the vulnerable areas regarding the photovoltaic power generation facility across the nation. GIS was used in the spatial analysis to develop a map for assessing the optimal location for photovoltaic power generation facility. The final vulnerability map developed in this study did not reveal any areas that exhibit vulnerability level 5 (very high) or 1 (very low). Jeollanam-do showed the largest value of vulnerability level 4 (high), while a large value of vulnerability level 3 (moderate) was shown by several administrative districts including Gwangju metropolitan city, Jeollabuk-do, Chungcheongbuk-do, and Gangwon-do. A value of vulnerability level 2 (low) was shown by the metropolitan cities including Daegu, Ulsan, and Incheon. When the 30 currently operating solar power plants were compared and reviewed, most were found to be in an area of vulnerability level 2 or 3, indicating that the locations were relatively suitable for solar energy. However, the limited data quantity for solar power plants, which is the limitation of this study, prevents the accuracy of the findings to be clearly established. Nevertheless, the significance of this study lies in that an attempt has been made to assess the vulnerability map for photovoltaic power generation facility targeting various regions across the nation, through the use of the GIS-based spatial analysis technique that takes into account the diverse meteorological and geographical factors. Furthermore, by presenting the data obtained for all regions across the nation, the findings of this study are likely to prove useful as the basic data in fields related to the photovoltaic power generation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.6
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• pp.52-59
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• 2010

As electric power demand of customers is constantly increasing, more bulk power systems are needed to install in a network. By development of renewable energies and high-efficient facilities and deregulated electricity market, moreover, the amount of distributed resource is considerably increasing in distribution network consequently. Also, distribution network has become more and more complex as mesh network to improve the distribution system reliability and increase the flexibility and agility of network operation. These changes make fault current increase. Therefore, the fault current will exceed a circuit breaker capacity. In order to solve this problem, replacing breaker, changing operation mode of system and rectifying transformer parameters can be taken into account. The SFCL(Superconducting Fault Current Limiter) is one of the most promising power apparatus. This paper proposes a methodology for on optimal location of SFCL. This place is defined as considering the decrement of fault current by component type and the increment of reliability by customer type according to an location of SFCL in a distribution network connected with DG(Distributed Generation). With case studies on method of determining optimal location for SFCL applied to a radial network and a mesh network respectively, we proved that the proposed method is feasible.

• Resources Recycling
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• v.22 no.2
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• pp.53-61
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• 2013

Since the 2000s, to start inducement of SCR(Selective Catalytic Reduction) denitrification facility by large scale companies which are emitted large amount of nitrogen oxides such as power plants, combined heat and power plant, incinerators and chemical plants due to take effect the regulation of stationary sources of nitrogen oxide(NOx), and the total amount of discharged pollutants, such as regulatory gradually emissions regulations are being strengthened and the expanded coverage due to the use of SCR denitrification catalyst is a growing trend. Since 2010 due to the new catalysts to replace the already installed power plants and incinerators due to inactive, and catalytic denitrification SCR waste catalyst waste as a resource rather than the development of technologies for recycling situation is urgently needed. In this study, analyzed paper and patent for recycling technologies of waste catalyst. The range of search was limited in the open patents of USA (US), European Union (EP), Japan (JP), Korea (KR) and SCI journals from 1975 to 2012. Patents and journals were collected using key-words searching and filtered by filtering criteria. The trends of the patents and journals was analyzed by the years, countries, companies, and technologies.

• Journal of the Korea Society for Simulation
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• v.16 no.2
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• pp.27-35
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• 2007

When sensor networks are deployed in open environments, all the sensor nodes are vulnerable to physical threat. An attacker can physically capture a sensor node and obtain the security information including the keys used for data authentication. An attacker can easily inject false reports into the sensor network through the compromised node. False report can lead to not only false alarms but also the depletion of limited energy resource in battery powered sensor networks. To overcome this threat, Fan Ye et al. proposed that statistical on-route filtering scheme(SEF) can do verify the false report during the forwarding process. In this scheme, the choice of a security threshold value is important since it trades off detection power and energy, where security threshold value is the number of message authentication code for verification of false report. In this paper, we propose a fuzzy rule-based system for security threshold determination that can conserve energy, while it provides sufficient detection power in the SEF based sensor networks. The fuzzy logic determines a security threshold by considering the probability of a node having non-compromised keys, the number of compromised partitions, and the remaining energy of nodes. The fuzzy based threshold value can conserve energy, while it provides sufficient detection power.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.2
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• pp.136-142
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• 2016

As the rapid industrialization and modernization progress of the world it is becoming a fast-paced environment pollution. And, dust or environment pollution to solve reckless diggings of natural aggregate cause a serious problem. This study was used a Blast Furnace Slag and Combined Heat and Power Plant of Fly Ash as a cement substitute to reduce $CO_2$ emissions during cement production, this study intend to suggest it's result as basic data 'Properties of Artificial Stone interior or exterior materials type utilizing industrial by-product and waste resource' utilizing Waste Porcelain and Waste Glass. As a result, it was high strength that matrix added the Combined Heat and Power Plant of Fly Ash of addition ratio 40%. Also, pre-experiment was conduct as mixing ratio of waste glass, waste porcelain on the basis of the preceding experiment, proper mixing ratio was judged that proper of waste glass, waste porcelain was mixing ratio 60, 70 (%) of appeared surface aggregate ratio more than 45%.