• Clean Technology
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• v.29 no.3
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• pp.193-199
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• 2023

Biomass has been used to secure renewable energy certificates (REC) in domestic and overseas coal-fired power plants. In recent years, biofuel has been diversified from traditional wood pellets to non-woody biomass. Non-woody biomass has a higher content of alkaline metals such as K and Na than wood-based biomass, resulting in a lower melting point and an increase in slagging on boiler tubes, which reduces boiler efficiency. This study analyzed the effect of kaolin, an additive commonly used to increase melting points, on biomass co-firing to coal through thermochemical equilibrium calculations. In a previous experiment on biomass co-firing to coal conducted at 80 kW_th, it was interpreted that the use of kaolin actually increased the amount of fouling. In this study, analysis showed that when kaolin was added, aluminosilicate compounds were generated due to Al₂O₃, which is abundant in coal, and mullite was formed. Thus, it was confirmed that the amount of slag increased when more kaolin was used. Further analysis was conducted by increasing the biomass co-firing rate from 0% to 100% at 10% intervals, and the results showed non-linear liquid slag generation. As a result, it was found that the least amount of liquid slag was generated when the biomass co-firing rate was between 50 and 60%. The phase diagram analysis showed that high melting point compounds such as leucite and feldspar were most abundantly generated under these conditions.

• Korean Journal of Environmental Biology
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• v.41 no.1
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• pp.18-30
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• 2023

Forest destruction is an inevitable result of the development processes. According to the environmental impact assessment, over 10% of the destroyed trees need to be recycled and transplanted to minimize the impact of forest destruction. However, the rate of successful transplantation is low, leading to a high rate of tree death. This is attributable to a lack of consideration for environmental factors when choosing a temporary site for transplantation and inadequate management. To monitor transplanted trees, a field survey is essential; however, the spatio-temporal aspect is limited. This study evaluated the applicability of remote sensing for the effective monitoring of transplanted trees. Vegetation indices based on satellite remote sensing were derived to detect time-series changes in the status of the transplanted trees at three temporary transplantation sites. The mortality rate and vitality of transplanted trees before and after the transplant have a similar tendency to the changes in the vegetation indicators. The findings of this study showed that vegetation indices increased after transplantation of trees and decreased as the death rate increased and vitality decreased over time. This study presents a method for assessing newly transplanted trees using satellite images. The approach of utilizing satellite photos and the vegetation index is expected to detect changes in trees that have been transplanted across the country and help to manage tree transplantation for the environmental impact assessment.

• Journal of Environmental Impact Assessment
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• v.33 no.1
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• pp.1-8
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• 2024

Amphibians are a taxonomic group that ecologically connects terrestrial ecosystems and aquatic ecosystems. They play a very important role in the food chain of the ecosystem. It is known that there are about 5,948 species distributed all over the world, but after the Industrial Revolution, due to industrialization and urbanization, there has been a decrease in species and populations. In particular, it is becoming a factor in exacerbating habitat fragmentation or fragmentation due to artificial canals. In orderto improve the survivalrate of wild animals in artificial canals, escape facilities are installed to reduce it. This study analyzed the slope, height of the escape facility, escape rate, and travel distance in the operating facility for Bombina orientalis, which mainly inhabits near forests. The slope of the escape facility showed a relatively similar escape success rate regardless of height at 50° and 60°, while at 70°, it showed a relatively high escape success rate at only 40cm in height. The success rate of escape from the waterway escape facility in operation was 14.71%, showing a very low utilization rate, and the recognition rate of the artificial canal escape facility was found to be very low as it moved along the side wall of the artificial canal. Therefore, in the case of a waterway escape facility for Bombina orientalis, it is possible to construct it at an angle of 60°, and if the side walls of the artificial canals are built within 60°, Bombina orientalis can move freely in both directions, overcoming the low utilization rate of existing waterway escape facilities. It is expected to minimize the impact of movement and death of artificial canals. In addition, if the spacing between escape facilities is narrowed from the installation standard of 30m and ramps are constructed in both directions upstream and downstream, the escape success rate of amphibians,reptiles, and small mammals otherthan lady frogs is expected to improve.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.2
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• pp.129-140
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• 2014

This study was performed to evaluate the effects of replacing basic total mixed ration (TMR) with fermented soybean curd, Artemisia princeps Pampanini cv. Sajabal, and spent coffee grounds by-product on rumen microbial fermentation in vitro. Soybean in the basic TMR diet (control) was replaced by the following 9 treatments (3 replicates): maximum amounts of soybean curd (SC); fermented SC (FSC); 3, 5, and 10% FSC + fermented A. princeps Pampanini cv. Sajabal (1:1, DM basis, FSCS); and 3, 5, 10% FSC + fermented coffee meal (1:1, DM basis, FSCC) of soybean. FSC, FSCS, and FSCC were fermented using Lactobacillus acidophilus ATCC 496, Lactobacillus fermentum ATCC 1493, Lactobacillus plantarum KCTC 1048, and Lactobacillus casei IFO 3533. Replacing dairy cow TMR with FSC treatment led to a pH value of 6 after 8 h of incubation-the lowest value measured (p<0.05), and FSCS and FSCC treatments were higher than SC and FSC treatment after 6 h (p<0.05). Gas production was higher in response to 3% FSC and FSCC treatments than the control after 4-10 h. Dry matter digestibility was increased 0-12 h after FSC treatment (p<0.05) and was the highest after 24 h of 10% FSCS treatment. $NH_3-N$ concentration was the lowest after 24 h of FSC treatment (p<0.05). Microbial protein content increased in response to treatments that had been fermented by the Lactobacillus spp. compared to control and SC treatments (p<0.05). The total concentration of volatile fatty acids (VFAs) was increased after 6-12 h of FSC treatment (p<0.05), while the highest acetate proportion was observed 24 h after 5% and 10% FSCS treatments. The FSC of propionate proportion was increased for 0-10 h compared with among treatments (p<0.05). The highest acetate in the propionate ration was observed after 12 h of SC treatment and the lowest with FSCS 3% treatment after 24 h. Methane ($CH_4$) emulsion was lower with A. princeps Pampanini cv. Sajabal and spent coffee grounds treatments than with the control, SC, and FSC treatments. These experiments were designed to replace the by-products of dairy cow TMR with SC, FSC, FSCS, and FSCC to improve TMR quality. Condensed tannins contained in FSCS and FSCC treatments, which reduced $CH_4$ emulsion in vitro, decreased rumen microbial fermentation during the early incubation time. Therefore, future experiments are required to develop a rumen continuous culture system and an in vivo test to optimize the percentages of FSC, FSCS, and FSCC in the TMR diet of the dairy cows.