• Title/Summary/Keyword: 중국과학원

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Characteristics of Meiofauna Community Inhabiting Continental Shelf of Yellow Sea, Korea (황해 대륙붕에 서식하는 중형저서동물 군집 특성)

  • JUNG, MIN GYU;KIM, DONGSUNG;KANG, TEAWOOK;OH, JE HYEOK;SHIN, AYONG;OH, CHUL WOONG
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.27 no.2
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    • pp.103-125
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    • 2022
  • This study aims to identify the community characteristics of meiofauna inhabiting the Yellow Sea continental shelf. To this end an annual survey was conducted considering the seasons from 2018 to 2020 at 13 stations with a depth of 18~90 m of the Yellow Sea located at latitudes 35, 36 and 37 degrees north latitude. The survey was conducted in three seasons of spring, summer, and autumn at 5 stations in October 2018, 9 stations in April 2019, and 6 stations in August 2020 was used to collect 3 repetitions at each station. The habitat density of meiobenthos in the surveyed area was in the range of 45~1029 inds./10 cm2, which was similar to the previous studies conducted in the Yellow Sea. The density of meiobenthos according to the seasons was 800±69 inds./10 cm2 in autumn, the highest, and the lowest at 260±48 inds./10 cm2 in summer. A total of 19 taxa appeared in meiobenthos, and the average value showed the number of nine taxa. Among the appearing taxa, the most dominant taxon was nematodes, accounting for 80.8% of the total density, followed by benthic copepods (8.8%) and benthic foraminifers (4.7%). As for the size distribution of medium benthic animals, the density of organisms corresponding to the size of 63~125 ㎛ was the highest, and 1~0.5 mm was the lowest. As for the vertical distribution in the sediments of medium benthic animals, the habitat density gradually decreased as the depth increased in the sediment surface layer. As a result of analysis of the N/C ratio, MPI, and ITD index using medium-sized benthic animals to identify the benthic environment, there were differences by season, but no values indicating pollution overall.

Estimation of High Resolution Sea Surface Salinity Using Multi Satellite Data and Machine Learning (다종 위성자료와 기계학습을 이용한 고해상도 표층 염분 추정)

  • Sung, Taejun;Sim, Seongmun;Jang, Eunna;Im, Jungho
    • Korean Journal of Remote Sensing
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    • v.38 no.5_2
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    • pp.747-763
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    • 2022
  • Ocean salinity affects ocean circulation on a global scale and low salinity water around coastal areas often has an impact on aquaculture and fisheries. Microwave satellite sensors (e.g., Soil Moisture Active Passive [SMAP]) have provided sea surface salinity (SSS) based on the dielectric characteristics of water associated with SSS and sea surface temperature (SST). In this study, a Light Gradient Boosting Machine (LGBM)-based model for generating high resolution SSS from Geostationary Ocean Color Imager (GOCI) data was proposed, having machine learning-based improved SMAP SSS by Jang et al. (2022) as reference data (SMAP SSS (Jang)). Three schemes with different input variables were tested, and scheme 3 with all variables including Multi-scale Ultra-high Resolution SST yielded the best performance (coefficient of determination = 0.60, root mean square error = 0.91 psu). The proposed LGBM-based GOCI SSS had a similar spatiotemporal pattern with SMAP SSS (Jang), with much higher spatial resolution even in coastal areas, where SMAP SSS (Jang) was not available. In addition, when tested for the great flood occurred in Southern China in August 2020, GOCI SSS well simulated the spatial and temporal change of Changjiang Diluted Water. This research provided a potential that optical satellite data can be used to generate high resolution SSS associated with the improved microwave-based SSS especially in coastal areas.

Accumulation of Natural and Artificial Radionuclides in Marine Products around the Korean Peninsula: Current Studies and Future Direction (국내산 수산물 내 자연 및 인공방사능 축적 연구 현황 및 향후 연구 방향)

  • Lee, Huisu;Kim, Intae
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.5
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    • pp.618-629
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    • 2021
  • The Fukushima nuclear power plant (NPP) accident caused by the East Japan Earthquake in 2011 and the recent increase in the frequency of earthquakes in Korea have caused safety concerns regarding radionuclide exposure. In addition, the Tokyo Electric Power Company (TEPCO) in Japan recently decided to release radionuclide-contaminated water from Fukushima's NPP into the Pacific Ocean, raising public concerns that the possibility of radionuclide contamination through both domestic- and foreign fishery products is increasing. Although many studies have been conducted on the input of artificial radionuclides into the Pacific after the Fukushima NPP accident, studies on the distribution and accumulation of artificial radionuclides in marine products from East Asia are lacking. Therefore, in this study, we attempted to explore recent research on the distribution of artificial radionuclides (e.g., 137Cs, 239+240Pu, 90Sr, and etc.) in marine products from Korean seas after the Fukushima NPP accident. In addition, we also discuss future research directions as it is necessary to prepare for likely radiation accidents in the future around Korea associated with the new nuclear facilities planned by 2030 in China and owing to the discharge of radionuclide-contaminated water from the Fukushima NPP.

Manufacturing technique and provenance Analysis of Bronze Artefacts excavated from Pungnap earthen fortress (풍납토성 출토 청동유물의 제작기술 및 납 원료의 산지추정)

  • Han, Woo Rim;Kim, So Jin;Han, Min-su;Hwang, Jin-ju;Lee, Eun-woo
    • Korean Journal of Heritage: History & Science
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    • v.48 no.2
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    • pp.110-119
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    • 2015
  • Bronzes, Earthenwares and various artifacts were excavated from Pungnap earthen fortress in the early Baekje age in Korea. This study was performed in order to identify the manufacture technology of bronze artefacts and provenance of lead in bronzes. Microstructure and chemical composition results show that 3 of them are Cu-Sn-Pb alloys in which an intentional lead addition was carried out and one is tin bronze showing straight twin structure within crystal grains. Also $CuFeS_2$ or $Cu_5FeS_4$ was used as raw materials through the detection of S and Fe as trace elements. The lead isotope results could be matched with one of the zones of southern Korea and China on the East Asian map. This results shows that data were plotted either in zone 2 or zone 3 of the South Korean galena map. However, one of bronze artifacts was matched with the zone of Northern China.

Estimation of TROPOMI-derived Ground-level SO2 Concentrations Using Machine Learning Over East Asia (기계학습을 활용한 동아시아 지역의 TROPOMI 기반 SO2 지상농도 추정)

  • Choi, Hyunyoung;Kang, Yoojin;Im, Jungho
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.275-290
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    • 2021
  • Sulfur dioxide (SO2) in the atmosphere is mainly generated from anthropogenic emission sources. It forms ultra-fine particulate matter through chemical reaction and has harmful effect on both the environment and human health. In particular, ground-level SO2 concentrations are closely related to human activities. Satellite observations such as TROPOMI (TROPOspheric Monitoring Instrument)-derived column density data can provide spatially continuous monitoring of ground-level SO2 concentrations. This study aims to propose a 2-step residual corrected model to estimate ground-level SO2 concentrations through the synergistic use of satellite data and numerical model output. Random forest machine learning was adopted in the 2-step residual corrected model. The proposed model was evaluated through three cross-validations (i.e., random, spatial and temporal). The results showed that the model produced slopes of 1.14-1.25, R values of 0.55-0.65, and relative root-mean-square-error of 58-63%, which were improved by 10% for slopes and 3% for R and rRMSE when compared to the model without residual correction. The model performance by country was slightly reduced in Japan, often resulting in overestimation, where the sample size was small, and the concentration level was relatively low. The spatial and temporal distributions of SO2 produced by the model agreed with those of the in-situ measurements, especially over Yangtze River Delta in China and Seoul Metropolitan Area in South Korea, which are highly dependent on the characteristics of anthropogenic emission sources. The model proposed in this study can be used for long-term monitoring of ground-level SO2 concentrations on both the spatial and temporal domains.

Study on the Geochemical Characteristics of the Mesozoic Volcanic Rocks in Da Hinggan Ling Area, Northeast China (중국 북동부 대흥안령 지역 중생대 화산암류에 대한 암석화학적 특성 연구)

  • Yun, Sung-Hyo;Won, Chong-Kwan;Lee, Moon-Won;Lin, Qiang
    • Journal of the Korean earth science society
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    • v.21 no.1
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    • pp.67-80
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    • 2000
  • We studied petrological and geochemical characteristics of the Mesozoic volcanic rocks in the Da Hinggan Ling area northeast China, and discussed tectonic settings and origin of the Mesozoic volcanic rocks in northeast Asia. Volcanic rocks in Da Hinggan Ling area are composed of alkaline to subalkaline basalt-basaltic andesite-andesite-dacite-rhyolite, showing typical BAR(basalt-andesite-rhyolite) association. However, most of the volcanic rocks are basaltic and rhyolitic in composition, and andesitic rocks are relatively rare, which shows bimodal characteristics. Rb, Ba, Th and other incompatible element contents in the volcanic rocks are enriched, but the contents decrease with increasing the compatibility. REEs are fractionated and REE patterns of volcanic rocks are characterized by a high LILE/HFSE. On the tectonomagmatic discriminant diagram of Hf-Th-Nb, they fall into the fields for subduction-related destructive plate margin basalts and its differentiates. We suggest that the tectonomagmatic setting of Da Hinggan Ling area was located at the continental margin arc related with subduction environment during the Mesozoic time or may be derived from mantle plume contaminated geochemically from subducting slabs, although it is, at present within the Asia continent.

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Income Analysis on the Cultivation of Major Medicinal Herbs (주요 약초류 재배에 대한 소득분석)

  • Kang, Hag Mo;Chang, Cheol Su;Kim, Hyun;Choi, Soo Im
    • Journal of Korean Society of Forest Science
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    • v.104 no.3
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    • pp.495-502
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    • 2015
  • This study intended to provide basic data required in establishing policies for improving the forestry management and the compensation standard for the loss from non-timber forest products by examining the cost of cultivating key medicinal herbs and the earnings from them to analyze the income. According to the income analysis on the cultivation of medicinal herbs, the average annual income per unit area of Adenophora triphylla var. japonica Hara was the highest as it recorded 14,233,000 won/10a and was followed by Pleuropterus multiflorus TURCZ. which recorded 4,121,000 won/10a, Gastrodia elata Blume 3,766,000 won/10a, Epimedium koreanum Nakai 3,537,000 won/10a, Atractylodes ovata (Thunb.) DC. 2,655,000 won/10a, Aralia continentalis Kitagawat 1,048,000 won/10a, Paeonia lactiflora Pallas 1,025,000 won/10a, and Bupleurum falcatum L. 919,000 won/10a. Compared with the income from major nuts and fruits analyzed in 2014, the average annual income per unit area for medicinal herbs was relatively higher. For Adenophora triphylla var. japonica Hara and Aralia continentalis Kitagawat, soots are used for food and the roots for medicine, it appears that it can become a new income source for the farming and mountain villages. Meanwhile, the price for Paeonia lactiflora Pallas is dropping due to Chinese imports, and also damage to the income from other medicinal herbs due to Chinese imports is expected with the implementation of Korea-China FTA in the future.

Trends and Issues of Tibetan History in Taiwan (대만의 티베트사(史) 연구 동향과 쟁점)

  • Sim, HyukJoo
    • 동북아역사논총
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    • no.60
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    • pp.196-227
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    • 2018
  • The issues of this study are as follows. First, I will examine the overall situation and transition trends of Tibetan research in Taiwan since the modern period, and examine the development and trends of Tibetan history research in Taiwan. Secondly, in order to satisfy the above, we will analyze trends of Taiwan's major Tibetan research institutes and scholars, and trace their trends and their trajectories. Third, the trend of Tibetan research in Taiwan may be a useful indicator for us to analyze research methods and trends of Taiwanese scholars. If there is a flow of features and transitions, the text will explore the reason. Fourth, one of the implications of this study is that it can trigger an understanding of locality in the structure of the central region, the Han Chinese minority, and the possession and distribution of academic reasoning. In other words, it should be noted that even though the same Tibetan research is conducted, China is in the position of the vested right to distribute 226 | 동북아역사논총 60호the central or ownership, while Taiwan has historical and territorial characteristics that deviate from such a gaze and attitude. Taiwan may be sensitive to the vertical concept understood as a change in the relationship between the state and the center, or whether it is applicable to Tibetan research. If there is such an academic climate, I would like to consider suggestions for us. This may provide a direction to view the academic issues of a few scholars, or even the domestic academic world as an independent object of more specific academic research.

Analysis of secondary curriculum and textbooks for cultural diversity education in China (중국의 문화다양성 교육을 위한 중등교육과정 및 교과서 분석)

  • Zang, Juanjuan;Jeong, Jiyeun
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.7 no.9
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    • pp.833-840
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    • 2017
  • This study was attempted to explore in depth the education of cultural diversity in the curriculum and textbooks of middle school according to [1] As a result, the educational goals in the curriculum emphasized[2] the realization of the meaning and value of cultural diversity education reflecting the global citizen education in various time, space background and socio-cultural context. The purpose of the curriculum guidelines is specified, and the following is given: "To properly recognize the diversity of the world culture; To acquire knowledge on cultural diversity; To grasp important functions in the city life, and to have attitudes and qualities required as members of the world, and to develop a pluralistic literacy ability''. In the textbooks, the subjects of the cultural diversity education are mainly based on the curriculum standards, the education area of the 7th grade is the 'human community life', the education area of the 8th grade is the origin and development of the Chinese civilization, Suggesting the scope of the theme 'harmonious coexistence with the world'. In order to analyze cultural diversity education in response to the demands of the times, we analyzed three factors such as diversity, identity, and interrelationship.

A Study on the Nature observation and Scientific methodology in Zhōuyì周易 - Focusing on its association with Contemporary Science (『주역(周易)』의 자연관찰과 과학적 방법론에 관한 연구 - 『주역(周易)』에 나타난 현대자연과학적 의미를 중심으로 -)

  • Shin, Jungwon
    • (The)Study of the Eastern Classic
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    • no.71
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    • pp.99-128
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    • 2018
  • Zhōuyì周易 is intended to explain the affairs of human beings by observing the images and works of all things in the universe, abstracting them into the $b{\bar{a}}gu{\grave{a}}$八卦, calculating the process and inducing the outcome by the method of stalk divination, in which this paper finds the origin of natural scientific thought of Zhōuyì. The way of Zhōuyì's thought on the natural science is distinguished from that of the Western's. In the West, people dismantled the objects into the parts until they reached the atom and analyzed them by the principle of causality to draw an axiomatic truth. In the meantime Zhōuyì observed and studied the dynamic functions and changes of all things for the convergence of the whole. While the way of Zhōuyì's thinking could have not contributed to the development of modern scientific development, that of the West overwhelmed Asian development passing through the period of enlightenment during 16-17 century. This paper tries to articulate the points where Zhōuyì can share its theory with the contemporary science by finding the traces of scientific thoughts in Zhōuyì. It encounters its ground from the methodology of natural science and scientific statements proposed by Zhōuyì. The essential concepts of Zhōuyì are induced from all things in nature. This can be considered as the idea of '法自然'(emulating the patterns and examples from nature). Also they observed the images and changes seen by the habits of animals, plants and human beings to sense and perceive their laws. These are regarded as the methodology of natural science in Zhōuyì. As a book of divination, the way of stalk divination is designed to calculate the future by using the system of 'numbers'. 'tàijí太極', ' yīnyáng陰陽', 'four symbols四象', '$b{\bar{a}}gu{\grave{a}}$八卦' and 'wǔxíng五行' are the essential concepts of Zhōuyì to represents the dynamic phenomena and changes of the natural order. Among them '$b{\bar{a}}gu{\grave{a}}$八卦' is a presentment to explain the structure of the world not by the individual analysis of things but by the unification of the whole through the contradictions and interchanges among them to reach the new orders. As of now, the studies of Zhōuyì in Korea have focused on the traditional perspectives, such as political and ethical philosophy. Some of recent studies, having interpreted Zhōuyì with scientific inclination have generated controversy 'Can Zhōuyì be a science?', for which scholars have hard time to reach the agreement. This paper tries to find the headwaters of the contemporary natural science by elaborating the methodology of natural science stated in Zhōuyì.