• Nuclear Engineering and Technology
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• 제54권12호
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• pp.4474-4480
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• 2022

Deep geological disposal using a multibarrier system is a promising solution for treating high-level radioactive (HLRW) waste. The HLRW canister represents the first barrier for the migration of radionuclides into the biosphere, therefore, the corrosion behavior of canister materials is of significance. In this study, the electrochemical behaviors of SS316L, Ti-Gr.2, Alloy 22, and Cu in naturally aerated KAERI underground research tunnel (KURT) groundwater solutions were examined. The corrosion potential, current, and impedance spectra of the test materials were recorded using electrochemical methods. According to polarization and impedance measurements, Cu exhibits relatively higher corrosion rates and a lower corrosion resistance ability than those exhibited by the other materials in the given groundwater condition. In the anodic dissolution tests, SS316L exposed to the groundwater solution exhibited the most uniform corrosion, as indicated by its surface roughness. This phenomenon could be attributed to the extremely low concentration of chloride ions in KURT groundwater.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.58-58
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• 2022

With the development of advanced technology, automation of agricultural work is spreading. In association with the 4th industrial revolution-based technology, research on field smart farm technology is being actively conducted. A state-of-the-art unmanned automated agricultural production demonstration complex was established in Naju-si, Jeollanam-do. For the operation of the demonstration area platform, it is necessary to build a sophisticated, advanced, and intelligent field smart farming model. For the operation of the unmanned automated agricultural production demonstration area platform, we are building data on the growth of soybean for smart cultivated crops and conducting research to determine the optimal time for agricultural work. In order to operate an unmanned automation platform, data is collected to discover digital factors for water management immediately after planting, water management during the growing season, and determination of harvest time. A subsurface drip irrigation system was established for smart water management. Irrigation was carried out when the soil moisture was less than 20%. For effective water management, soil moisture was measured at the surface, 15cm, and 30cm depth. Vegetation indices were collected using drones to find key factors in soybean production prediction. In addition, major growth characteristics such as stem length, number of branches, number of nodes on the main stem, leaf area index, and dry weight were investigated. By discovering digital factors for effective decision-making through data construction, it is expected to greatly enhance the efficiency of the operation of the unmanned automated agricultural production demonstration area.

• 한국산업융합학회 논문집
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• 제27권1호
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• pp.77-86
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• 2024

Urban Air Mobility (UAM) is considered the future of transportation, offering solutions to urban challenges and reducing environmental issues through the use of electric power and leveraging the sky as a new transportation corridor. UAM has diverse applications, including passenger and goods transportation, emergency rescue operations, patient transfers, and urban tourism. Furthermore, it is poised to revolutionize the transportation landscape, impacting existing infrastructures such as roads and parking lots, along with autonomous vehicles. The UAM industry is anticipated to exert a significant impact on various sectors, including airframe manufacturing, the development of new materials (e.g., fuel cells and batteries), and even the defense industry, resulting in substantial economic benefits. Consequently, conducting proactive research and setting industry standards for UAM takeoff and landing infrastructure is crucial for securing market leadership. In this regard, the case of Pontoise-Cormeiles, France, stands out as it achieved the world's inaugural successful demonstration of a vertiport before the 2024 Olympics. This achievement has significant implications for our preparations for the commercialization of UAMs. Thus, a detailed review of the French vertiport construction case in this study will serve as a foundation for guiding the planning and operation of UAMs in South Korea, particularly in anticipation of upcoming demonstration tests.

• Asian-Australasian Journal of Animal Sciences
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• 제13권6호
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• pp.830-836
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• 2000

A participation scheme involving smallholder dairy farmers in improving dairy productivity through the use of local feeds, on-farm established feeds and crop residues was carried out in the Northeast, Thailand. At six milk collection centers, 63 farmers with 340 lactating cows participated in this research and demonstration of feed supplements. Farmers and cows were allotted to receive respective feed supplements: high-quality feed block (HQFB), high-quality feed pellet (HQFP), dried cassava leaf/cassava hay, dried leucaena leaf and cottonseed meal: 5% urea treated rice straw was fed as a source of roughage throughout the feeding period of the dry season. Trainings and workshops were organized by the researchers at the University, research station, demonstration sites and on-farms. Regular visits to the fartns by researchers and extension officers were made while discussions and demonstrations were performed in addition. Participating farmers also visited other farmers during the demonstration which offered a real practical perspective and farmer-to-farmer interaction. As a result of this participation and demonstration scheme, the farmers could learn more effectively and accepted the technology more readily, especially the practicality of the feed preparation, feed establishment, feeding method and feed reserve. Strategic supplementation of these feed supplements resulted in improving milk yield, milk quality, overall condition of the cows and higher income return through increased productivity and lower level use of concentrate to milk yield from 1:2 to 1:3 or lower. Based on this research and demonstration /participation scheme, all feed supplements enhanced productivity, however the establishment of cassava hay on fartns deserved more attention and warrants a wider developmental expansion among dairy farmers since it contained high rumen by-pass protein (tannin-protein complex) and could be easily produced and be sustainable on farms.

• 한국정보과학회논문지:소프트웨어및응용
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• 제37권5호
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• pp.363-369
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• 2010

데모-기반 학습은 사용자가 직접 작업을 시연함으로써 로봇에게 쉽게 새로운 작업지식을 가르칠 수 있다는 장점이 있다. 하지만 기존의 많은 데모-기반 학습법들은 상태공간과 정책들을 표현하기 위해 속성-값 벡터 모델을 이용하였다. 속성-값 벡터 모델의 제한성으로 인해, 이들은 학습과정의 효율성도 낮고 학습된 정책의 재사용성도 낮았다. 본 논문에서는 기존의 속성-값 모델 대신 관계적 모델을 이용하는 새로운 데모-기반 작업 학습법을 제안한다. 이 방법에서는 사용자 데모 기록에서 추출한 훈련 예들에 관계적 개체-기반 학습법을 적용함으로써, 동일 작업영역내의 다른 유사한 작업들에도 활용하기 용이한 관계적 개체-기반 정책을 유도한다. 이 관계적 정책은 (상태, 목표) 쌍으로 표현되는 임의의 한 상황에 대해 이것에 대응하는 하나의 실행동작을 결정해주는 역할을 한다. 본 논문에서는 데모-기반 관계적 정책 학습법에 대해 자세히 소개한 후, 로봇 시뮬레이터를 이용한 실험을 통해 이 학습법의 효과를 분석해본다.

• 에너지공학
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• 제21권2호
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• pp.179-186
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• 2012

온실가스의 증가로 인한 기후변화가 큰 이슈로 대두되고 있는 시점에서 순산소발전 실증사업은 화석에너지를 이용한 발전 부문의 이산화탄소 저감을 위한 한 가지 방안으로 주목을 받고 있다. 순산소발전 실증사업으로 인해 발생하는 전력공급 편익, 온실가스 저감 편익, 환경오염 물질 배출저감 편익, 국내외 시장 진출로 인한 부가가치 창출편익을 추정한다. 이러한 배경 하에서 내부수익률, 편익/비용 비율, 순현재가치의 기준을 이용하여 순산소발전 실증사업의 경제적 타당성을 분석하고자 한다. 순산소발전 실증사업의 경제적 타당성을 분석한 결과, 순산소발전 실증사업의 순현재가치, 편익/비용 비율, 내부수익률은 각각 681,620백만원, 1.69, 21.4%로 분석되었다. 이 분석결과들은 각각 0, 1.0, 5.5%를 초과하므로, 3가지 경제성 판단 지표 모두 본 사업이 경제적 타당성을 확보함을 의미한다. 이러한 분석 결과는 화력발전부문의 온실가스 저감을 위한 정책결정에 있어서 유용하게 활용될 수 있다.

• 임상간호연구
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• 제17권3호
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• pp.411-420
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• 2011

Purpose: The purpose of this study was to develop and evaluate a new-nurse education program utilizing both e-learning and instructor demonstration. Methods: From August to December in 2009, the e-learning education program about insulin injection was developed. The control (C) group was educated via instructor demonstration from April 15 to October 6 in 2009, and the experimental (E) group was educated via both e-learning and instructor demonstration from January 5 to October 13 in 2010. After each education, knowledge and educational effectiveness were checked. Results: Satisfaction with the education contents in the E group was significantly higher than those of the C group (Z=-3.72, p<.001), and satisfaction with the education method in the E group was higher than those of the C group (Z=-2.98, p=.003). Usefulness (Z=-3.33, p=.001), application (Z=-2.62, p=.009), and confidence (Z=-2.61, p=.009) in the E group were all higher than those of the C group. 78.9% in the E group reused the e-learning program after the experimental education. Conclusion: Combined educational program with e-learning and instructor demonstration had both merits of online efficiency and face-to-face education. It would be useful especially for new-nurses to improve their nursing skills in accomplishing their roles.

• 융합정보논문지
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• 제11권12호
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• pp.244-253
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• 2021

본 연구는 화재 발생 시 스마트폰 네비게이션 어플리케이션을 이용한 화재 대피 유도 서비스 시스템이 화재대피 시간에 어떤 영향을 미치는지 살펴보고자 하는 연구이다. 컴퓨터 시나리오 시뮬레이션에서 네비게이션 어플리케이션을 사용하였을 때 대피시간이 22초 단축되었고 실증시뮬레이션 또한 네비게이션 어플리케이션을 사용하였을 때 대피시간이 40초 감소되어 화재 발생 시 피난 시간 단축에 효과적이라는 점을 알 수 있다. 실증 시나리오 시뮬레이션을 한 결과는 피난유도를 실시한 경우가 실시하지 않은 경우보다 피난 종료까지 시간이 39초 더 빠르게 나타났다. 실증 시나리오 시뮬레이션은 피난 경로에 병목현상이 발생하지 않았고 이로인해 컴퓨터 시나리오 시뮬레이션과 실증 시나리오 시뮬레이션의 대피 완료 소요시간의 차이가 발생하였다. 추후 시나리오 시뮬레이션에 학생실습 연구에 기여할 것이다.

• 한국기계가공학회지
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• 제20권2호
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• pp.107-119
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• 2021

The cross-flow turbine is one of the most famous and widely used hydraulic power systems for a long time. The cross-flow turbine is especially popular in many countries and remote regions where off-grided because of its many benefits such as low cost, high efficiency at low head, simple structure, and easy maintenance. However, most modern turbines, including the cross-flow turbine, are unsuitable for the ultra-low head situation, known as less than 3m water head or zero head with over 0.5m/s flow velocity. In this study, we demonstrated a 20kW class inverted-type cross-flow turbine's performance. First, we reevaluated our previous studies and introduced how to design the inverted-type cross-flow turbine. Secondly, we fabricated the 20kW class inverted-type cross-flow turbine for the performance test. And then, we designed a testbed and installed the turbine system in the demonstration facility. In the end, we compare the demonstration with its previous CFD results. The comparing result shows that both CFD and real model fitted on guide vane angle at 10 degrees. At the demonstration, we achieved 42% turbine efficiency at runner speed 125 RPM.

• Journal of Microbiology and Biotechnology
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• 제31권2호
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• pp.240-249
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• 2021

Phenotypic plasticity is a rapid response mechanism that enables organisms to acclimate and survive in changing environments. The Chinese mitten crab (Eriocheir sinensis) survives and thrives in different and even introduced habitats, thereby indicating its high phenotypic plasticity. However, the underpinnings of the high plasticity of E. sinensis have not been comprehensively investigated. In this study, we conducted an integrated gut microbiome and muscle metabolome analysis on E. sinensis collected from three different environments, namely, an artificial pond, Yangcheng Lake, and Yangtze River, to uncover the mechanism of its high phenotypic plasticity. Our study presents three divergent gut microbiotas and muscle metabolic profiles that corresponded to the three environments. The composition and diversity of the core gut microbiota (Proteobacteria, Bacteroidetes, Tenericutes, and Firmicutes) varied among the different environments while the metabolites associated with amino acids, fatty acids, and terpene compounds displayed significantly different concentration levels. The results revealed that the gut microbiome community and muscle metabolome were significantly affected by the habitat environments. Our findings indicate the high phenotypic plasticity in terms of gut microbiome and muscle metabolome of E. sinensis when it faces environmental changes, which would also facilitate its acclimation and adaptation to diverse and even introduced environments.