• Corrosion Science and Technology
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• 제22권3호
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• pp.187-192
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• 2023

The use of biomass is increasing as a response to the convention on climate change. In Korea, a method applied to replace fossil fuels is using wood chips in a cogeneration plant. To remove air pollutants generated by burning wood chips, a selective denitrification facility (Selective catalytic reduction, SCR) is installed downstream. However, problems such as ash deposition and descaling of the equipment surface have been reported. The cause is thought to be unreacted ammonia slip caused by ammonia ions injected into the reducing agent and metal corrosion caused by an acidic environment. Element analysis confirmed that ash contained alkali metals and sulfur that could cause catalyst poisoning, leading to an increase in the size of ash particle and deposition. Measurement of the size of ash deposited inside the facility confirmed that the size of ash deposited on the catalyst was approximately three times larger than the size of generally formed ash. Therefore, it was concluded that a reduction in pore area of the catalyst by ash deposition on the surface of the catalyst could lead to a problem of increasing differential pressure in a denitrification facility.

• Genomics & Informatics
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• 제20권4호
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• pp.45.1-45.7
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• 2022

Food security will be affected by climate change worldwide, particularly in the developing world, where the most important food products originate from plants. Plants are often exposed to environmental stresses that may affect their growth, development, yield, and food quality. Auxin is a hormone that plays a critical role in improving plants' tolerance of environmental conditions. Auxin controls the expression of many stress-responsive genes in plants by interacting with specific cis-regulatory elements called auxin-responsive elements (AuxREs). In this work, we performed an in silico prediction of AuxREs in promoters of five auxin-responsive genes in Zea mays. We applied a data fusion approach based on the combined use of Dempster-Shafer evidence theory and fuzzy sets. Auxin has a direct impact on cell membrane proteins. The short-term auxin response may be represented by the regulation of transmembrane gene expression. The detection of an AuxRE in the promoter of prolyl oligopeptidase (POP) in Z. mays and the 3-fold overexpression of this gene under auxin treatment for 30 min indicated the role of POP in maize auxin response. POP is regulated by auxin to perform stress adaptation. In addition, the detection of two AuxRE TGTCTC motifs in the upstream sequence of the bx1 gene suggests that bx1 can be regulated by auxin. Auxin may also be involved in the regulation of dehydration-responsive element-binding and some members of the protein kinase superfamily.

• 한국수자원학회논문집
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• 제56권7호
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• pp.431-438
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• 2023

전 세계적으로 연안침식 문제가 대두됨에 따라 많은 해안선이 지형변화를 겪고 있다. 기후변화 및 해안인구증가로 미루어 볼 때 그 현상은 가속화될 수 있으며, 이에 대응하기 위해 신속하게 지형변화를 모의할 수 있는 유사이송 예측모형 개발의 중요성이 강조된다. 본 연구에서는 GPU (Graphics Processing Unit)를 기반으로 한 유사이송 예측모형을 제안하였으며, GPU 병렬연산을 활용함으로써 기존의 CPU 기반모형 대비 더욱 개선된 속도로 지형변화를 모의할 수 있도록 모형이 개발되었다. 개발된 모형에 대해 수치모형 성능과 GPU 연산효율에 초점을 맞추어 분석을 수행하였다. 모형의 성능검증을 위해 Dam-break 수리실험에 대해 수치모의를 수행하였으며, 모의결과가 관측된 실험데이터와 잘 일치하는 것을 확인하였다. GPU 연산효율은 CPU 기반모형과 수치모의 연산시간을 비교하여 분석하였으며, 개발된 GPU 기반모형이 연산시간의 효율이 상당히 우수한 것으로 확인되었다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.211-211
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• 2022

The marketization reform from the open-door policy in 1978 was not only booming export-oriented industries with foreign investment but also expanding the role of private actors in the Chinese water sector. Private Sector Participation (PSP) has become an important element in developing urban infrastructure by providing better services with advanced facilities. The rapid development of PSP-driven urban water infrastructure in China has a positive impacted on Chinese economic development, particularly in coastal areas. PPPs in some coastal areas have successfully spread out over China since China applied the first Build-Operate-Transfer (BOT) mode in the water sector in the early 1990s. The market-oriented water and wastewater, Public-Private Partnership (PPP) mechanism in the initial period of China has been transformed into a state-dominated PPP mechanism. The development pattern of the water and wastewater PPPs in China has been divided in four stages: the first period from 1984 to 2002, the second period from 2003 to 2008, the third period from 2009 to 2014, and the last period after 2015. The study aims to investigate the successful process of water and wastewater PPPs in local areas through five socioeconomic elements: export-oriented economic strategy, urbanization, cheap land policy, infrastructure investment, and water issues and climate change. In addition, the study focuses on analyzing the extent to which the Chinese government re-asserted its control over the PPP mechanism by classifying five elements in three different development Phases from early 2000 to 2020. The Jiangsu Province in the estern coastal area has actively invited PPP projects in the water and wastewater sectors. The successful introduction and rapid growth of PPPs in the urban water infrastructure has made the province an attractive area for a foreign investor.

• Journal of Animal Science and Technology
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• 제65권5호
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• pp.939-950
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• 2023

This study was conducted to assess the impact of growing condition variables on alfalfa (Medicago sativa L.) productivity. A total of 197 alfalfa yield results were acquired from the alfalfa field trials conducted by the South Korean National Agricultural Cooperative Federation or Rural Development Administration between 1983 and 2008. The corresponding climate and soil data were collected from the database of the Korean Meteorological Administration. Twenty-three growing condition variables were developed as explaining variables for alfalfa forage biomass production. Among them, twelve variables were chosen based on the significance of the partial-correlation coefficients or potential agricultural values. The selected partial correlation coefficients between the variables and alfalfa forage biomass ranged from -0.021 to 0.696. The influence of the selected twelve variables on yearly alfalfa production was summarized into three dominant factors through factor analysis. Along with the accumulated temperature variables, the loading scores of the daily mean temperature higher than 25℃ were over 0.88 in factor 1. The sunshine duration at temperature between 0℃-25℃ was 0.939 in factor 2. Precipitation days were 0.82, which was the greatest in factor 3. Stepwise regression applied with the three dominant factors resulted in the coefficients of factors 1, 2, and 3 for 0.633, 0.485, and 0.115, respectively, and the R-square of the model was 0.602. The environmental conditions limiting alfalfa growth, such as daily temperature higher than 25℃ or daily mean temperature affected annual alfalfa production most substantially among the growing condition variables. Therefore, future cultivar selection should consider the capability of alfalfa to be tolerant to extreme summer weather along with biomass production potential.

• 한국농공학회논문집
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• 제65권5호
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• pp.1-11
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• 2023

Due to climate change and aging of reservoirs, damage to embankment slopes is increasing. However, the safety diagnosis of the reservoir slope is mainly conducted by visual observation, and the time and economic cost are formidable to apply soil mechanical tests and slope stability analysis. Accordingly, this study presented a predicting method for the compaction and strength characteristics of the reservoir embankment soil using a portable static cone penetration test. The predicted items consisted of dry density, cohesion, and internal friction angle, which are the main factors of slope stability analysis. Portable static cone penetration tests were performed at 19 reservoir sites, and prediction equations were constructed from the correlation between penetration resistance data and test results of soil samples. The predicted dry density and strength parameters showed a correlation with test results between R² 0.40 and 0.93, and it was found to replace the test results well when used as input data for slope stability analysis (R² 0.8134 or more, RMSE 0.0320 or less). In addition, the prediction equations for the minimum safety factor of the slope were presented using the penetration resistance and gradient. As a result of comparing the predicted safety factor with the analysis results, R² 0.5125, RMSE 0.0382 in coarse-grained soil, R² 0.4182 and RMSE 0.0628 in fine-grained soil. The results of this study can be used as a way to improve the existing slope safety diagnosis method, and are expected to be used to predict the characteristics of various soils and inspect slopes.

• 한국농공학회논문집
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• 제65권5호
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• pp.13-24
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• 2023

Due to recent climate change, the amount of rainfall during the summer season in South Korea has been decreasing, leading to an increase in areas affected by frequent droughts. Droughts have the characteristic of occurring over a wide area and being unpredictable in terms of their onset and end, necessitating proactive research to cope with them. In this study, we conducted an assessment of agricultural drought vulnerability in Taean-gun, Chungcheongnam-do, focusing on irrigation facilities and paddy fields. The assessment criteria were meteorological impact, drought occurrence status, supplementary water supply capacity, and drought response capability, with nine specific indicators selected. The drought response capability was analyzed by applying a scoring system as a key component of the agricultural drought vulnerability assessment, while the other indicators were quantified using an entropy weighting technique. The results of the assessment showed that Anmyeon-eup and Taean-eup were the safest areas, while Wonbuk-myeon, Nam-myeon, and Gonam-myeon were the most vulnerable. It is expected that the findings can be utilized to enhance understanding and proactive measures for coping with agricultural drought, and to determine the priority of drought response in different regions.

• 한국지반공학회논문집
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• 제39권10호
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• pp.27-39
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• 2023

극한홍수에 대응하기 위한 홍수 위험도 관리의 필수 요소인 홍수 위험도 평가를 위해서는 댐 및 하천제방과 같은 홍수방어시설에 대하여 여러 파괴 메커니즘을 고려한 신뢰도 해석을 수행해야 한다. 본 연구에서는 수위급강하에 의한 제체 사면의 시간에 따른 확률론적 안정성 평가에 대하여 연구하였다. 유한요소 해석에 의한 침투해석 결과를 사면안정 해석에 연동하여 Monte Carlo Simulation을 수행함으로써 수위급강하에 따른 제체의 시간의존적 거동을 연구하고 파괴확률을 계산하여 제방의 취약도 곡선을 작성하였다. 수위급강하에 의한 사면의 파괴확률은 특정 수위까지는 매우 작은 값을 유지하지만, 그 이상에서는 수위가 증가함에 따라 급격하게 증가하는 현상을 보였다. 또한 취약도 곡선은 수위 하강 속도에 크게 영향을 받았다. 수위 저하 속도는 수문 시나리오에 의한 수위의 변동해석을 통하여 결정되므로 수위급강하에 따른 제방 제외지 사면의 안정성은 기후변화에 따라 크게 영향을 받을 것으로 판단된다.

• Journal of the Korean Wood Science and Technology
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• 제51권6호
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• pp.555-568
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• 2023

The diffusion strategies of wood culture were established using the analytic hierarchy process, to prepare a diffusion plan of wood culture and wood utilization in response to climate change due to global warming. 'Standardization of wood culture', 'Valuation of wood culture', and 'Habituation of wood culture' were set as three major implementation strategies and priorities were evaluated. As a result, it was analyzed in the following order: 'Development of systematic education programs for each age group for rational and efficient use of eco-friendly wood materials and development of wood education standard guidelines linked to the curriculum', 'Preparation of scientific basis data on human compatibility and eco-friendliness of wood to ensure the reliability of wood and wood products', and 'Establishment of monitoring and improvement plan through the designation as a model school'. Through this, it was determined that an educational environment, changes in public attitudes through publicity, and expanding opportunities to use wood and wood products were necessary for wood culture diffusion. The results of this study can be used as basic data to derive the diffusion strategies of wood culture and establish a roadmap and policy implementation strategy to revitalize wood culture.

• 한국인터넷방송통신학회논문지
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• 제24권3호
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• pp.69-76
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• 2024

이 논문은 도시 내 지속 가능한 식량 생산을 위한 5층 구조의 수직형 농축수산 팜(팜 타워) 모델을 개발하였다. 해양농장, 축산, 무농약 자동화 농작물 팜을 통합해 자원을 효율적으로 사용하고 환경 영향을 최소화하는 방안을 제안한다. 순환 경제 원칙에 기반한 이 모델은 각 부분의 산출물을 다른 부분의 자원으로 재활용하여 시스템의 효율을 증진시키며 도시 내 유휴 공간을 활용하고, 일자리 창출과 지역 사회 참여를 촉진할 수 있다. 또한, 식량 생산의 탄소 발자국을 줄이고, 식품 안전성을 향상시키는 데 기여할 수 있다. 추가적으로, 이 연구는 진보된 농업 기술이 도시 구조에 통합되어 글로벌 식량 안보 문제에 대응할 수 있는 방안을 모색한다. 이 모델은 기후 변화와 인구 증가로 인한 식량 위기에 대한 잠재적 해결책을 제시하며, 도시 농업의 발전 방향을 제안한다. 향후 연구에서는 실제 구현을 위한 기술적, 정책적 과제를 다루어야 할 것이다.