• Journal of Ecology and Environment
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• 제47권4호
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• pp.228-240
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• 2023

Growing complexity in ecosystem structure and functions, under impacts of climate and land-use changes, requires interdisciplinary understandings of processes and the whole-system, and accurate estimates of the changing functions. In the last three decades, observation networks for biodiversity, ecosystems, and ecosystem functions under climate change, have been developed by interested scientists, research institutions and universities. In this paper we will review (1) the development and on-going activities of those observation networks, (2) some outcomes from forest carbon cycle studies at our super-site "Takayama site" in Japan, and (3) a few ideas how we connect in-situ and satellite observations as well as fill observation gaps in the Asia-Oceania region. There have been many intensive research and networking efforts to promote investigations for ecosystem change and functions (e.g., Long-Term Ecological Research Network), measurements of greenhouse gas, heat, and water fluxes (flux network), and biodiversity from genetic to ecosystem level (Biodiversity Observation Network). Combining those in-situ field research data with modeling analysis and satellite remote sensing allows the research communities to up-scale spatially from local to global, and temporally from the past to future. These observation networks oftern use different methodologies and target different scientific disciplines. However growing needs for comprehensive observations to understand the response of biodiversity and ecosystem functions to climate and societal changes at local, national, regional, and global scales are providing opportunities and expectations to network these networks. Among the challenges to produce and share integrated knowledge on climate, ecosystem functions and biodiversity, filling scale-gaps in space and time among the phenomena is crucial. To showcase such efforts, interdisciplinary research at 'Takayama super-site' was reviewed by focusing on studies on forest carbon cycle and phenology. A key approach to respond to multidisciplinary questions is to integrate in-situ field research, ecosystem modeling, and satellite remote sensing by developing cross-scale methodologies at long-term observation field sites called "super-sites". The research approach at 'Takayama site' in Japan showcases this response to the needs of multidisciplinary questions and further development of terrestrial ecosystem research to address environmental change issues from local to national, regional and global scales.

• Restorative Dentistry and Endodontics
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• 제15권1호
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• pp.141-152
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• 1990

The purpose of this study was to evaluate the effects of dentin adhesives(Gluma$^{(R)}$ and Scotchbond 2$^{(R)}$) on the marginal adaptation of light cured composite resin (Heliosit$^{(R)}$) by using SEM. The recently extracted 30 teeth were used and round cavities were prepared on the occlusal surfaces of the teeth with predesigned depth and diameter. The teeth were divided into three groups. Group 1 : Gluma$^{(R)}$ + Heliosit$^{(R)}$ Group 2 : Scotchbond 2$^{(R)}$ + Heliosit$^{(R)}$ Group 3 : Enamelbond$^{(R)}$ + Heliosit$^{(R)}$ Filling with Heliosit, the teeth were stored in saline solution for 24 hours. After the thermocycling procedure, the teeth were cut vertically into the restorations. The SEM observation was carried out to evaluate the marginal adaptation of the composite resin. The following results were obtained. The following results were obtained. 1. The groups using Gluma$^{(R)}$ and Scotchbond 2$^{(R)}$ showed better than the control group on marginal adaptation to the dentin. 2. The group using Gluma$^{(R)}$ was superior to the group using Scotchbond 2$^{(R)}$, but the difference was not significant. 3. In all groups, the marginal gaps were wider on the pulpal walls than on the lateral walls of restorations.

• 한국전자통신학회논문지
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• 제8권7호
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• pp.1049-1064
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• 2013

본 연구의 목적은 2012년 UN 전자정부 세계 순위 평가에서 2010년에 이어 2회 연속 1위로 평가 받은 바 있는 한국의 전자정부를 개발도상국을 중심으로 수출할 수 있는 효과적인 방안을 모색하기 위함이다. 물론 현재까지 개별 부처나 기관별로는 관련 시스템의 수출을 위해 나름대로 노력해 왔으나, 종합적이고 체계적인 접근은 부족한 것으로 파악된다. 따라서 본 연구에서는 전자정부 수출 기업 지원을 위한 기존 부처나 기관 중심의 추진전략에서 나타난 미흡한 점을 분석하여 한국 전자정부의 수출을 촉진할 수 있는 현실적이고 중장기적인 전략과 지원 방법을 모색하고자 한다. 또한, 본 연구는 실증적 연구로서 기존 정부부처 및 기관별로 추진하고 있는 전자정부 수출전략을 분석하여 그 개선점을 진단하고, 바람직한 목표모델과의 간극을 메우기 위한 방안을 제시하고자 하며, 향후 보다 적실성이 높으며 효과성을 높일 수 있는 방안을 모색해 보고자 한다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.459-464
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• 2006

It has been well proved that shiphandling simulators are efficient and useful facilities for training and education of cadets and seafarers. Most of the maritime universities and many maritime training institutes all over the world have installed shiphandling simulators, which play important roles in maritime education and training. However, most of the Shiphandling simulators are standalone facilities with diversities on system architectures, layouts and functions. STCW78/95 requires simulators used for simulator-based training shall be suitable for the selected objectives and training tasks. To ensure the shiphandling simulator facilities meet the requirements of STCW convention and other expanded applications, collaborated research and coordination are needed in development and application of shiphandling simulators. Performance standard should be established for shiphandling simulator systems considering the advanced research needs as well as the needs in education, training, and assessment of competence. Standardizing and exchanging shiphandling mathematical models will improve critical performance of the system. Cooperated research on model course and training assessment approaches will enhance the training standard. In addition, the rapid spread of the internet technology has shown a promising future of application of shiphandling simulators through internet. Research has been carried out on internet based integration of multiple shiphandling simulators. A multi-agent based system, including necessary hardware, has been developed. Collaborated operation of the system can be of benefit in filling the gaps of the technical and operational level and methodology between maritime universities, enhancing mutual understanding of the navigation customs and culture background among cadets and seafarers from different countries, facilitating communication and maritime English training, and extending the functions of shiphandling simulators.

• Applied Microscopy
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• 제29권1호
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• pp.67-73
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• 1999

분말시료를 epoxy로 포매 (embedding)한 후 ion milling하는 방법으로 TEM 시편을 준비하는 경우에는 시료와 epoxy와의 milling정도의 차이 때문에 좋은 시편을 만들기 어렵다. 이러한 문제점을 극복하기 위해서 포매 물질에 대한 분말시료의 상대 밀도를 높여 주는 방법을 시도하였다. 일반적인 진공법보다는 원심분리기법을 이용하여 포매하는 것이 시료의 밀도를 높일 수 있었다. 또한, 비슷한 크기의 분말의 혼합보다는 서로 다른 크기의 분말을 혼합한 후 원심분리기를 이용하여 포매할 때, 큰 입자들 사이로 작은 입자들이 유입되면서 분말의 밀도가 더욱 높아지는 것을 알 수 있었다. 이렇게 준비된 시료는 ion milling정도의 차이에서 오는 문제점을 크게 줄일 수가 있어 TEM 관찰에 필요한 시편을 얻을 수 있었다. 원심분리기법은 마이크로미터 이하 크기의 구형, 판상 및 침상의 분말시료에서부터 TEM 시편을 준비하는 데에도 매우 효과적임이 드러났다.

• 영어영문학
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• 제64권3호
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• pp.433-451
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• 2018

In Jesmyn Ward's 2017 novel, Sing, Unburied, Sing, Ward places herself within the modern African American literary tradition and lays out the unending "historical traumas" of blacks and cultural haunting in her narrative. She brings to the fore the story of a young black boy and demonstrates the difficulty of living while a black man in the American rural South. Living or dead, black males remain spectral as their frustrated black bodies are endlessly rejected and disembodied. It's through Ward's close attention to the notions of black masculinity and retrieval of (black) humanity that the black South is remembered, recuperated, and historicized. Shrewdly enough, Ward expands it further into the tradition of American literature. Instead of singularizing African American identity and its historical traumas, she renders them the part of American history and universalizing the single black story as the story of the American South. Filling in the gaps that Faulkner and other white writers have left in their novels, Ward writes stories about the unspeakable, the invisible, the excluded to deconstruct white narratives and rebuild the American history; and reasserts African roots and history, spirituality, black raciality and locality within the American tradition. I examine the symbolic significance of Jojo's claim of black masculinity within the socio-political contexts of contemporary America. I also look closely at Ward's portrayal of Jojo's black family genealogy on account of its traumatic experiences of incarceration in notorious Parchman Farm. Locating Jojo as the inspiration of linking the past and the present, the unburied and the living, I contend that Ward creates "home" for blacks in an atemporal oceanic space where the past and the present are able to meet simultaneously. I argue that the oceanic space is an alternative space of affect that functions against the space of white rationality.

• 아태비즈니스연구
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• 제14권1호
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• pp.341-350
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• 2023

Purpose - How are gains from trade distributed between countries when economic integration is achieved through free trade? The purpose of this paper is to answer this question. Design/methodology/approach - This study attempts to address the issue of distribution of trade gains between participating countries following economic integration in terms of positive economics. The analysis is therefore based on a theoretical methodology. Findings - First, commodity prices fall and consumer surplus increases in both large and small countries. Second, when economic integration into free trade is achieved, gains from trade always exist in small countries. However, the size of trade gains depends on the degree of difference from the market size of the partner country, the large country. However, the size of the gains from trade depends on the extent of difference between the market size of the large country. If the market size of a large country is much larger and there is a large difference, trade gains will be very large, whereas if the market size is similar, profits of domestic firm will decrease. Therefore, in that case, the size of the gains from trade becomes relatively small because only the gains from exchange exists. On the other hand, in a large country with a large market size, there is a possibility of trade gains only when the market size is similar to that of a small country, which is a trading partner. However, if there is a large difference in market size, the decrease in profits of domestic firm is relatively larger than the increase in consumer surplus due to trade, and rather, a trade loss occurs. Research implications or Originality - Our analysis contributes to filling the gaps in the literature regarding the distribution of gains from trade, and from a policy point of view, it is meaningful in examining the impact of market size, an important variable considered in regional economic integration of countries.

• Composites Research
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• 제37권5호
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• pp.369-374
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• 2024

본 연구에서는 수평 정렬 탄소나노튜브 나노복합재료(Horizontally Aligned Carbon Nanotube, HACNT)의 에폭시와 아세톤의 희석비율 및 프레스 압력에 따라 CNT 부피분율, 가스 투과도, 전기저항을 측정 및 분석하였다. 연구 결과, 희석비율이 감소하고 프레스 압력이 증가함에 따라 CNT 부피분율은 증가하였고, 이는 에폭시의 점도와 압력 조건이 CNT의 간극을 채우는 데 중요한 역할을 한다는 것을 시사한다. 이에 CNT 부피분율이 증가 함에 따라, 전기 저항 및 가스 투과도가 감소하게 되어 최적의 물성을 갖게 된다. 본 연구는 새롭게 제조된 HACNT 나노복합재의 성능을 최적화하기 위한 적절한 희석비율 및 프레스 압력 조건을 제시하여,다양한 분야에서 잠재적인 활용 가능성을 시사한다.

• Korean Circulation Journal
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• 제54권6호
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• pp.295-310
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• 2024

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 has led to a global health crisis with substantial mortality and morbidity. To combat the COVID-19 pandemic, various vaccines have been developed, but unexpected serious adverse events including vaccine-induced thrombotic thrombocytopenia, carditis, and thromboembolic events have been reported and became a huddle for COVID-19 vaccination. Vaccine-related myocarditis (VRM) is a rare but significant adverse event associated primarily with mRNA vaccines. This review explores the incidence, risk factors, clinical presentation, pathogenesis, management strategies, and outcomes associated with VRM. The incidence of VRM is notably higher in male adolescents and young adults, especially after the second dose of mRNA vaccines. The pathogenesis appears to involve an immune-mediated process, but the precise mechanism remains mostly unknown so far. Most studies have suggested that VRM is mild and self-limiting, and responds well to conventional treatment. However, a recent nationwide study in Korea warns that severe cases, including fulminant myocarditis or death, are not uncommon in patients with COVID-19 VRM. The long-term cardiovascular consequences of VRM have not been well understood and warrant further investigation. This review also briefly addresses the critical balance between the substantial benefits of COVID-19 vaccination and the rare risks of VRM in the coming endemic era. It emphasizes the need for continued surveillance, research to understand the underlying mechanisms, and strategies to mitigate risk. Filling these knowledge gaps would be vital to refining vaccination recommendations and improving patient care in the evolving COVID-19 pandemic landscape.

• 해양환경안전학회지
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• 제18권6호
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• pp.545-550
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• 2012

풍력발전 단지의 설계시 풍력 자원 평가 과정은 필수적인 과정이다. 풍력 자원 평가를 위해 장기풍황(20년)자료를 이용하여야 하지만 장기간 관측하는 것은 어렵기 때문에 예정지의 1년 이상의 관측데이터로 평가를 실시하였다. 예정지의 단기 풍황탑(Met-Mast; Meteorology Mast) 자료를 주변의 장기관측 자료인 자동기상관측(AWS; Automatic Weather Station)데이터를 이용하여 수학적 보간법으로 예정지의 데이터를 장기 데이터로 변환한 것을 MCP(Measure-Correlative-Predict)기법이라 한다. 본 연구에서는 MCP기법 중 선형 회계방법을 적용하였다. 선택된 MCP 회귀 모델식에 따라 제주 북동부 구좌지역의 AWS데이터를 제주 북동부 한동 지역의 Met-mast 데이터에 적용하여 연간 에너지 생산량을 예측 하였다. 예정지의 단기 풍황을 이용하였을 때와 보정된 장기 풍황을 이용하여 때 연간 에너지 생산량을 비교하였다. 그 결과 연간 약 3.6 %의 예측오차를 보였고, 이는 연간 약 271 MW의 에너지 생산량의 차이를 의미한다. 풍력발전기의 생애주기인 20년을 비교 하였을 때 약 5,420 MW의 차이를 나타내었으며, 이는 약 9개월 정도의 에너지 생산량과 비슷한 수준이다. 결과적으로, 제안 된 선형 회귀 MCP 방법을 이용하는 것이 단기관측 자료를 통한 불확식성을 제거하는 합리적인 방법으로 판단된다.