• Title/Summary/Keyword: the Yellow River

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Water Quality Characteristics Along Mid-western Coastal Area of Korea (한국 서해 중부 연안역의 수질환경 특성)

  • Lim, Dhong-Il;Kang, Mi-Ran;Jang, Pung-Guk;Kim, So-Young;Jung, Hoi-Soo;Kang, Yang-Soon;Kang, Young-Shil
    • Ocean and Polar Research
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    • v.30 no.4
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    • pp.379-399
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    • 2008
  • Spatial-temporal variations in physiochemical water qualities (temperature, salinity, DO, SPM, POC and nutrients) of surface and bottom waters were investigated along the mid-western coastal area (Taean Peninsula to Gomso Bay) of Korea. Spatial distribution patterns of temperature and salinity were mostly controlled by the physical mixing process of freshwater from Geum River and/or Gyunggi Bay with nearby coastal water. A strong tidal front is formed off Taean Peninsula during spring and summer. Seasonal variations in nutrient concentrations, lower in spring and summer and higher in fall and winter, are primarily regulated by magnitude of phytoplankton occurrence rather than freshwater loadings into the bay. Based on seasonal and spatial variability of physicochemical parameters, water quality of the study area can be divided into four water masses; Gyunggi Bay-influenced Water Mass (GBWM), Geum River-influenced Water Mass (GRWM), Yellow Sea Bottom Cold Water Mass (YSBCWM) and Cheonsu Bay Water Mass (CBWM). Water quality of the GBWM (Taean Peninsula coastal area), which has relatively low salinity and high concentrations of nutrients, is strongly controlled by the Gyunggi Bay coastal water, which is under influence of the Han River freshwater. In this water mass, the mixed layer is always developed by strong tidal mixing. As a result, a tidal front is formed along the offshore boundary of the mixed layer. Such tidal fronts probably play an important role in the distribution of phytoplankton communities, SPM and nutrients. The GRWM, with low salinity and high nutrients, especially during the flood summer season, is closely related to physiochemical properties of the Geum River. During the flood season, nutrient-enriched Geum River water mass extends up to 60 km away from the river mouth, potentially causing serious environmental problems such as eutrophication and unusual and/or noxious algal blooms. Offshore (<$30{\sim}40m$ in water depth) of the study area, YSBCWM coupled with a strong thermocline can be identified in spring-summer periods, exhibiting abundant nutrients in association with low temperature and limited biological activity. During spring and summer, a tidal front is formed in a transition zone between the coastal water mass and bottom cold water mass in the Yellow Sea, resulting in intensified upwelling and thereby supplying abundant nutrients to the GBWM and GRWM. Such cold bottom water mass and tidal front formation seems to play an important role in controlling water quality and further regulating physical ecosystem processes along mid-western Korean coastal area.

Geochemical Characteristics of Surface Sediments in the Eastern Part of the Yellow Sea and the Korean West Coast (황해 동부 대륙붕과 한반도 서해안 표층퇴적물의 지구화학적 특성)

  • 조영길;이창복;박용안;김대철;강효진
    • The Korean Journal of Quaternary Research
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    • v.7 no.1
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    • pp.69-91
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    • 1993
  • A total of 76 surface sediment samples, collected from the Korean west coast and the eastern Yellow Sea areas, were analyzed for their elemental composition in order to understand the geochemical characteristics of these deposits. The analyzed elements included 9 major elements (Al, Fe, Na, K, Mg, Ca, Ti, P, Mn), 8 minor elements (Sr, Ba, V, Cr, Co, Ni, Cu, Zn), organic carbon and calcium carbonate. Contents of most analyzed elements, excluding K and Ba, were generally low compared to those of average crust. Contents of most elements, except K and Ca, also correlated with sediment grain size, though the degree of relationship varied widely from one element to another. For fine-grained sediments, a distinction could be made between those in the central Yellow Sea and those in the Keum Estuary based on their characteristic elemental composition: the former were rich in Fe, Na, K, Mg, Ca and V, and the latter in Mn, Co and Ni. The element/aluminium ratios, on the other hand, showed that the central Yellow Sea muds were enriched in Fe, Mg, V, Ni, Cu and Zn and depleted in K, Mn, Ba and Sr relative to the mud located near the Korean Peninsula. Based on the analysis of these results, as well as of the influences of particular mineral phases or pollution effects, we could suggest geochemical criteria which can be used in distinguishing muds from the two different sources, the Keum River and the Yellow River: the former by the higher Mn content and the latter by the higher Mg and V contents, relative to each other.

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A Study on Harbor Logistics in China (중국의 항만 물류집중화에 관한 연구 - 상하이항과 장강을 중심으로 -)

  • Lee, Jong- Won
    • Journal of Navigation and Port Research
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    • v.31 no.3 s.119
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    • pp.187-195
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    • 2007
  • China has been the hub of business in Asia' and has developed infra-system and development policy on harbor and logistics. Investment on development of Sanghai port and fang river has been increasing. This development has put importance on logistics in East Asia Additionally, port surrounding of China has been activated Therefore, This paper is going to suggest three measures. First, shipping corporation of Korea will provide different services and network according to the growth of China logistics. Secondly, Korea is to invest with Chinese companies around fang river to freight service industry. Thirdly, it is to construct Yellow sea Rim transport network by Sanghai port and fang river development.

The relationships of erosion and river channel change in the Geum river basin (금강유역의 침식과 하상변동과의 관계)

  • 양동윤;짐주용;이진영;이창범;정혜정
    • The Journal of Engineering Geology
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    • v.10 no.2
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    • pp.52-74
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    • 2000
  • The basement rock of upper stream of Keum River Valley consists of Precambrian gneiss which is resistant to weathering. That of mid and lower stream valley, however, is mainly composed of Mesozoic granites which are vulnerable to weathering. The upstream part of Geum River Basin is typified by the deeply-incised and steep meandering streams, whereas mid and lower part is characterized by wide floodplain and gently dipping river bottom toward the Yellow Sea. In particular flooding deposits, in which are imprinted a number of repetitions of erosion and sedimentation during the Holocene, are widely distributed in the lower stream of Geum River Basin. For understanding of erosions in the mid and lower stream of Geum River Basin, the rate of erosion of each small basins were estimated by using the data of field survey, erosional experiments and GIS ananlysis. It was revealed that erosion rate appeared highest in granite areas, and overall areas, in this field survey were represented by relatively high erosion rates. By implemeatation of remote sensing and imagery data, the temporal changes of river bed sediments for about last 11 years were successfully monitored. Observed as an important phenomenon is that the river bed has been risen since 1994 when an embankment (Dyke) was constructed in the estuarine river mouth. From the results derived from the detailed river bed topographical map made in this investigation, the sedimentation of the lower river basin is considered to be deposited with about 5 cm/year for the last 11 years. Based on this river bed profile analysis by HEC-6 module, it is predicted that Geum River bed of Ganggyeong area is continuously rising up in general until 2004. Although extraction of a large amount of aggregates from Gongju to Ganggyung areas, the Ganggyung lower stream shows the distinct sedimentation. Therefore, it is interpreted that the active erosions of tributary basins Geum drainage basins can affect general river bed rising changes of Geum River.

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Shallow Water Tides in the Seas around Korea

  • Kantha, Lakshmi H.;Bang, In-Kweon;Choi, Jei-Kook;Suk, Moon-Sik
    • Journal of the korean society of oceanography
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    • v.31 no.3
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    • pp.123-133
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    • 1996
  • We describe here the shallow water tides in the seas around Korea, obtained from a nonlinear barotropic model of tides in a domain encompassing the Yellow Sea, the East China Sea and the East Sea (Sea of Japan). As expected, the shallow water tides are large in the shallow marginal areas around the Yellow Sea, with the M4 tide reaching amplitudes as high as 10 cm near the Korean coast, and quite small in the East Sea. However, we also find that the regions east of the Yangtze River ($126^{\circ}E,$ $30^{\circ}N$) in the East China Sea also sustain large shallow water tides, with $M_{4}$, amplitudes reaching 5 cm. Such large shallow water tides are an important component of altimeter-measured sea levels and should not be ignored in any altimetric analyses of the Yellow Sea and the East China Sea. This study also highlights the desirability of very high resolution models to derive accurate shallow water tides in coastal regions.

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Characteristics of Time Variations of PM10 Concentrations in Busan and Interpreting Its Generation Mechanism Using Meteorological Variables (부산 지역 미세먼지 농도의 시간변동 특성 및 기상인자 분석을 통한 먼지생성 해석)

  • Kim, Ji-A;Jin, Hyung-Ah;Kim, Cheol-Hee
    • Journal of Environmental Science International
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    • v.16 no.10
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    • pp.1157-1167
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    • 2007
  • In an effort to interpret the characteristics of fine particle concentrations in Busan, time variations of hourly monitored concentrations $PM_{10}$ (Particulate Matter with aerodynamic Diameter ${\le}10\;{\mu}m$) in Busan are analyzed for the period from 2000 to 2005. The characteristics of aerosol second generation formation process is also interpreted qualitatively, by using the statistical analysis of the meteorological variables including temperature, wind speed, and relative humidity. The result shows some significant annual, seasonal, weekly and diurnal variations of $PM_{10}$ concentrations. In particular, seasonal(i.e., spring) variations are governed by frequency of yellow sand events even for the non-yellow sand cases where yellow-sand days are eliminated in our analysis. However, in seasonal variation, summer season predominate lower $PM_{10}$ concentrations due to the frequent precipitation, and weekly and diurnal variations are both found to be reflecting the emission rate from traffic amount. Correlation coefficients between $PM_{10}$ concentration and meterological variables for non-yellow sand days show overall negative correlation with visibility, wind speed, cloud amounts, and relative humidity. However for non-precipitation days, during non-yellow sand period positive correlation are found clearly with relative humidity, suggesting the importance of secondary aerosol formation in Busan that can be achieved by both homogeneous aerosol formation and heterogeneous transformations resulting from hygroscopic aerosol characteristics.

The study on efficient transport system in Circle Yellow-Sea region using rail & sea multi transport system (철도-해운 복합운송 시스템을 이용한 환황해권 수송 효율화 연구)

  • Han, Ji-Young;Yoo, Jae-Kyun;Lee, Yoon-Mi
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.389-396
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    • 2010
  • After analyzing network of the region of western sea, which is the center of Circle Yellow-Sea economic region, and Circle Bo-Hai and the delta of a long river economic region, which are belong to three major economic region of China, as an efficient strategy, rail & sea multi-transport system of Korea-China joint SOC strategy is suggested. Rail & Sea multi-transport system, which is the links of railroads and shipping transport, can be subdivided into train-ferry, which is the transport of loaded trains into a vessel, and transshipment, which is transshipment of containers from railroads to vessels. And, the way of railroads transport through a tunnel under the sea is also suggested.

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A Study on the Removal of Microcystis aeruginosa by Coagulants of the Ceramic-Zeolite type and Yellow loess (응집제 Ceramic-Zeolite type과 황토를 이용한 Microcystis aeruginosa 제거에 관한 연구)

  • 박홍기;정은영;이유정;정종문;최식영;홍용기
    • Journal of Environmental Science International
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    • v.11 no.4
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    • pp.405-409
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    • 2002
  • For the proposal of Microcystis aeruginosa control technique by coagulants, removal effects of coagulants were carried out using isolated strain and collected water bloom of M. aeruginosa on Downstream of the Nakdong River. Both of purified and field-collected M. aeruginosa were entirely sedimented by the addition of the coagulant ceramic-zeolite type Co 100 (1.5 mg/$\ell$) within 24 hr, but Yellow loess (10 mg/$\ell$) was less effective for the removal of M. aeruginosa within 24hr. Thus it was concluded that Ceramic-Zeolite type Co 100 was the most effective coagulant.

The Relationship between Oceanographic Condition and Fishing Ground Distribution of Yellow Croaker in the East China Sea and the Yellow Sea (동지나해, 황해의 참조기 어장분포와 해황과의 관계)

  • YANG Seong-Ki;CHO Kyu-Dae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.15 no.1
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    • pp.26-34
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    • 1982
  • The East China Sea and the Yellow Sea are abundant in nutritions because of river inflows and are important as the nursery and spawning grounds of demersal and pelagic fishes. The remarkable thermal front between the Yellow Sea Bottom Cold Water and the Tsushima Warm Current is formed in this region, and the fluctuation of this front may affect the variation of the yellow croaker fishing ground. To investigate the mechanism of the yellow croaker fishing ground, the distribution ana seasonal change of the fishing ground are examined by using catch of stow net fishery (Fisheries Research and Development Agency, 1970-1979) and the water temperature data (Japan Hydrographic Association, 1978). The main fishing ground of yellow croaker was nine sea areas (rectangle of 30' latitude by 30' longitude) located at 40-150 nautical miles west and southwest of Jeju Island, the area of which occupies no more than $11\%$ of all fishing grounds, and it appeared that about $70\%$ of total catch of ten years was concentrated in this area. The main fishing periods were from March to May and September to October. The coefficients of variation of the catch for the main fishing ground were from 0.8 to 2.1 and the condition of all fishing grounds was generally unstable. The mean CPUE was 27kg/haul at the main fishing ground, while it was the largest on boundary area of the Yellow Sea Bottom Cold Water. It was found that the seasonal movement of fishing ground is related to the expansion and reduction of the Yellow Sea Bottom Cold Water ($10^{\circ}C$).

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The establishing process of Keyongyegimunrok(經義記聞錄) by Namdang Han Wonjin and the characteristic of illustrated accounts of Heart-mind theory (남당(南塘) 한원진(韓元震)의 『경의기문록(經義記聞錄)』 성립 과정과 심성론 도설(圖說)의 특징)

  • Lee, Chang-il
    • The Journal of Korean Philosophical History
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    • no.35
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    • pp.131-164
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    • 2012
  • This paper is to make a generalization of Keyongyegimunrok(經義記聞錄) by Namdang Han Wonjin(1682~1751) whose historical positions of philosophy were contained, and to examine its established periods and the summaries of Ligi-Simseong Doseol(理氣心性圖說, illustrated Account of principle, Vital force, and Heart-mind) given in Appendix of Chap. 6. Total seventeen explanatory diagrams cover over the theory of principle and material force, theory of Heart-mind, theory of cultivation. These explanatory diagrams were produced systematically and easily to understand the pursuits of study, so-called Ho-hak(湖學), since Namdang becoming a member of the Yellow River(黃江) school. The philosophical argumentations of Namdang was usually succeeded by the orthodox stream of Ki-ho(畿湖) School transmitted from Ii, Song Si-yeol, Gwon Sang-ha. Ligi-wollyu-do(理氣源流圖), Ligi-dongjeong-do(理氣動靜圖), irwon-bunsu-do(一原分殊圖, 4 diagrams) are diagrams equivalent to Ki-ho School's ontology. As Ki-ho School's theory of Heart-mind, there are Seongjeong-hoenggan-do(性情橫看圖), Seongjeong-sugan-do(性情竪看圖), Seongjeong-chonghwoi-do(性情總會圖), Oseonghoju-do (五性互主圖), Oseongchubon-do(五性推本圖), Simseongmyohap-do (心性妙合圖), Simseongiji-do(心性二岐圖), Jungyongcheonmyeong-do(中庸天命圖), Insim dosim-do(人心道心圖), focusing on Simtongseongjeong-do(心統性情圖), and last diagram is Wihakjibang-do(爲學之方圖), which adapted from the diagram established by Ii and Song Si-yeol. The significance of Keyongyegimunrok(經義記聞錄) is comprehensive of the pursuits of the Yellow River school's studies, and provides evidence of a leading figure in Ho-hak.