• Ocean and Polar Research
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• 제37권3호
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• pp.225-233
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• 2015

To understand the fluctuation of global carbon levels caused by the biogeochemical cycle within the ocean interior, it is essential to achieve comparability of global oceanic nutrient data to a fairly high degree. The Scientific Committee on Ocean Research (SCOR) commissioned a working group (WG147) to establish a system for achieving comparability of oceanic nutrient data within 1% among laboratories around the world. The introduction of international activities for improving nutrient comparability will facilitate the use of nutrient reference material of seawater by researchers within Korea, which will help in meeting international standards of nutrient comparability and promote international cooperation.

• The Korean Journal of Ecology
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• 제22권6호
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• pp.363-369
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• 1999

Reconstruction of the past vegetational changes of Korea in connection with climate changes enables to understand the impacts of past and future global warming on alpine vegetation. Despite the early appearance of the cold-tolerant vegetation since the Mesozoic Era. the occurrence of warmth-tolerant vegetation during the Oligocene and Miocene implies that most of alpine and subalpine vegetations have been confined to the alpine and subalpine belts of northern Korean Peninsula. The presence of cold-episodes during the Pleistocene. however. might have caused a general southward and downslope expansions of cold-tolerant alpine and subalpine vegetation. But the climatic warming trend during the Holocene or post-glacial period eventually has isolated cold-tolerant alpine and subalpine vegetation mainly in the northern Korea. but also on scattered high mountains in the southern Korea. The presence of numerous arctic-alpine and alpine plants on the alpine and subalpine belts is mainly due to their relative degree of sensitivity to high summer temperatures. Global warming would cause important changes in species composition and altitudinal distributional pattern. The altitudinal migration of temperate vegetation upward caused by climatic warming would eventually devastate alpine plants.

• 한국정밀공학회지
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• 제13권11호
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• pp.46-56
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• 1996

Planarization technique is rapidly recognized as a critical step in chip fabrication due to the increase in wiring density and the trend towards a three dimensional structure. Global planarity requires the preferential removal of the projecting features. Also, the several materials i.e. Si semiconductor, oxide dielectric and sluminum interconnect on the chip, should be removed simultaneously in order to produce a planar surface. This research has investihgated the development of the chemical mechanical polishing(CMP) machine with uniform pressure and velocity mechanism, and the pad insensitive to pattern topography named hard grooved(HG) pad for global planarization. Finally, a successful result of uniformity less than 5% standard deviation in residual oxide film and planarity less than 15nm in residual step height of 4 inch device wafer, is achieved.

• 지적과 국토정보
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• 제50권2호
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• pp.101-115
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• 2020

자율주행 분야 글로벌 동향 파악 및 공간정보 서비스 활성화 방안 도출을 위해 빅데이터 분석방법을 활용하였다. 사용된 빅데이터는 뉴스기사와 특허문헌을 상호 연계하여 활용하고, 뉴스 기사를 통한 동향 분석, 특허문헌 정보를 활용한 기술 분석이 진행 되었다. 본 논문에서는 자율주행에 대한 주요 뉴스에서 토픽모델을 기반으로 한 LDA(Latent Dirichlet Allocation)를 활용하여 빅데이터화 하고 주요 단어를 추출하였다. 특허정보의 주요 단어를 기반으로 적용된 워드넷(WordNet)을 활용하여 공간정보와 연계성 분석, 글로벌 기술 동향 분석을 실시하고 공간정보 분야의 동향 분석 및 예측을 실시하였다. 본 논문에서는 주요뉴스와 특허문헌 정보를 기반으로 한 빅데이터 분석방법으로 자율주행 분야와 공간정보와의 연계성 분석을 통하여 최신 동향과 미래를 예측하는 방법을 제시한다. 빅데이터 분석으로 도출된 자율주행 분야 공간정보의 글로벌 동향은 플랫폼 얼라이언스, 비지니스 파트너쉽, 기업 인수합병, 합작회사 설립, 표준화 및 기술개발로 도출되었다.

• 대기
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• 제27권1호
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• pp.1-16
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• 2017

In this study, trends of upper jet stream characteristics (intensity, altitude, latitude, and longitude) over the Asia-North Pacific region during the recent 30 (1979~2008) years were analyzed by using four reanalysis datasets (CFSR, ERA-Int., JRA-55, MERRA). We defined the characteristics of upper jet stream as the averages of mass weighted wind speed, mass-flux weighted altitude, latitude and longitude between 400 and 100 hPa. Due to the vertical averaging of jet stream characteristics, our results reveal a weaker spatial variabilities and trends than previous studies. In general, the four reanalysis datasets show similar jet stream properties (intensity, altitude, latitude and longitude) although the magnitude and trends are slightly different among the reanalysis datasets. The altitude of MERRA is slightly higher than that of others for all seasons. The domain averaged intensity shows a weakening trend except for winter and the altitude of jet stream shows an increasing trend for all seasons. Also, the meridional trend of jet core shows a poleward trend for all seasons but it shows a contrasting trend, poleward trend in the continental area but equatorward trend in the Western Pacific region during summer. The zonal trend of jet core is very weak but a relatively strong westward trend in jet core except for spring and winter. The trends of jet stream characteristics found in this study are thermodynamically consistent with the global warming trends observed in the Asia-Pacific region.

• Journal of Astronomy and Space Sciences
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• 제27권3호
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• pp.231-238
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• 2010

We analyzed global positioning system (GPS)-derived precipitable water vapor (PWV) trends of the Korea Astronomy and Space Science Institute 5 stations (Seoul, Daejeon, Mokpo, Milyang, Sokcho) where Korea Meteorological Administration meteorological data can be obtained at the same place. In the least squares analysis, the GPS PWV time series showed consistent positive trends (0.11 mm/year) over South Korea from 2000 to 2009. The annual increase of GPS PWV was comparable with the 0.17 mm/year and 0.02 mm/year from the National Center for Atmospheric Research Earth Observing Laboratory and Atmospheric InfraRed Sounder, respectively. For seasonal analysis, the increasing tendency was found by 0.05 mm/year, 0.16 mm/year, 0.04 mm/year in spring (March-May), summer (June-August) and winter (December-February), respectively. However, a negative trend (-0.14 mm/year) was seen in autumn (September-November). We examined the relationship between GPS PWV and temperature which is the one of the climatic elements. Two elements trends increased during the same period and the correlation coefficient was about 0.8. Also, we found the temperature rise has increased more GPS PWV and observed a stronger positive trend in summer than in winter. This is characterized by hot humid summer and cold dry winter of Korea climate and depending on the amount of water vapor the air contains at a certain temperature. In addition, it is assumed that GPS PWV positive trend is caused by increasing amount of saturated water vapor due to temperature rise in the Korean Peninsula. In the future, we plan to verify GPS PWV effectiveness as a tool to monitor changes in precipitable water through cause analysis of seasonal trends and indepth/long-term comparative analysis between GPS PWV and other climatic elements.

• 대한기계학회논문집A
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• 제29권9호
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• pp.1243-1252
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• 2005

A current trend of design methodologies is to make engineers objectify or automate the decision-making process. Numerical optimization is an example of such technologies. However, in numerical optimization, the uncertainties are uncontrollable to efficiently objectify or automate the process. To better manage these uncertainties, the Taguchi method, reliability-based optimization and robust optimization are being used. To obtain the target performance with the maximum robustness is the main functional requirement of a mechanical system. In this research, a design procedure for global robust optimization is developed based on the kriging and global optimization approaches. The DACE modeling, known as the one of Kriging interpolation, is introduced to obtain the surrogate approximation model of the function. Robustness is determined by the DACE model to reduce real function calculations. The simulated annealing algorithm of global optimization methods is adopted to determine the global robust design of a surrogated model. As the postprocess, the first order second-moment approximation method is applied to refine the robust optimum. The mathematical problems and the MEMS design problem are investigated to show the validity of the proposed method.

• Journal of Construction Engineering and Project Management
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• 제2권3호
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• pp.8-16
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• 2012

After the 2008 global financial crisis, the construction environment in South Korea continued change in the construction environment. Construction orders in 2011 have shown a downward trend compared with the previous year. Along with these changes in the construction market, the professional capabilities of construction project managers that are perceived as important also changed after the global financial crisis. Accordingly, this study was conducted to identify the major business capabilities of the current construction project managers and to determine which of these capabilities have undergone changes in terms of the importance accorded to them after the global financial crisis, and ultimately, to derive the construction project manager capability areas that need to be strengthened according to the changes in the construction environment. The capabilities of construction project managers were surveyed at two different time points: in 2007 and in 2010. The results show that the year 2010, after the global financial crisis, an increase in the perceived important capabilities of construction project managers compared with 2007. This results the impact of the changes in the construction environment on the importance of construction project managers. This study derived the ramifications of the early identification of systems and prospects according to the changes in the construction circumstances on more efficient onsite and human resources management, by considering the appropriate capabilities of the construction project managers.

• 복식문화연구
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• 제22권2호
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• pp.273-289
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• 2014

The purpose of this study is to identify the determinants of the susceptibility of global consumer culture. As determinants, materialism and self monitoring as psychological variables and fashion clothing product knowledge as clothing-related variable were included. It was hypothesized that both psychological variables and clothing-related variable influence susceptibility of global consumer culture. Data were gathered by surveying university students in Seoul metropolitan area, using convenience sampling, and 311 questionnaires were used in the statistical analysis. In analyzing data, exploratory factor analysis using SPSS and confirmatory factor analysis and path analysis using AMOS were conducted. Factor analysis of susceptibility of global consumer culture revealed four dimensions, 'social prestige' factor, 'quality perception' factor, 'conformity to others' factor, and 'conformity to consumption trend' factor. In addition, factor analysis of self monitoring revealed three dimensions, 'center-oriented attention' factor, 'situation-appropriate self-presentation' factor, and 'strategic displays of self-presentation' factor. The results showed that all the fit indices for the variable measures were quite acceptable. In addition, the overall fit of the model suggests that the model fits the data well. Tests of the hypothesized path show that all variables except for the one factor of self monitoring, 'center-oriented attention', and materialism influence all the factors of susceptibility of global consumer culture. The implications of these findings and suggestions for future study are also discussed.

• International Journal of Advanced Culture Technology
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• 제11권2호
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• pp.330-344
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• 2023

This research report cuts across management sciences (market strategy entry mode development) and innovative technology (Electric Vehicle (EV)) alongside measures to submerge global warming. The development of a successful entry mode for the electric Vehicle into the African continent is the main objective of the study. The study focuses on an analysis of how electric car manufacturers can enter the African market in other to achieve global sustainability and social responsibility. The methodology is based on identifying the factors that affect the choice of an entry mode into international markets by multinational companies desiring to leverage their revenue through a foreign market. It also offered a quantitative approach that can support the economic and sustainability entry mode model for EVs and a qualitative approach of Porter's five forces analysis as an entry mode coaching tool for EVs. These proxies are used in quite a wide range of multivariate statistical methods (trend analysis, ratio, and probability, comparative t-test technique, auto-regression, and ordinary least square technique). The result acknowledges joint venture and setting of the plant (physical presents) as the optimal entry mode in African EV market. It requires the EV manufacturers a tire-free emission innovation technology in order to optimize the global sustainability initiative.