• Title/Summary/Keyword: 사구

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Characteristics of the Vegetation in the Coastal Dunes near the Swimming Beaches on the East Sea Coast, South Korea (동해안 해수욕장 주변의 해안사구 식생 특성)

  • Cho, Woo;Song, Hong-Seon;Hong, Sung-Chul;Choi, Deog-Cheon
    • Korean Journal of Environment and Ecology
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    • v.23 no.6
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    • pp.499-505
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    • 2009
  • This study was carried out to investigate and evaluate the vegetations in the coastal dunes in the vicinity of swimming beaches on the East Sea, South Korea, and the vegetations that were investigated are as follows: Carex pumila community, Cynodon dactylon community, Zoysia macrostachya community, Rosa rugosa community, Vitex rotundifolia community and Carex kobomugi typical community. Some of these vegetations, such as Carex kobomugi, Calystegia soldanella, Ixeris repens, Elymus mollis, Lathyrus japonica, and Glehnia littoralis were found to be differential species which belongs to Caricion kobomugi of Glehnietea littoralis. It was also discovered that Vitex rotundifolia community was the most heterogeneous among vegetation communities of the coastal dunes surrounding swimming beaches, and Zoysia macrostachya community was most closely linked to the typical coastal dune vegetation community. Finally, Rosa rugosa community and Vitex rotundifolia community seemed to have formed near the hinterland of coastal dunes and swimming beaches respectively because of certain unnatural disturbances such as construction of buildings and facilities or natural disasters.

Beach and Sanddune Development along the Coastline of the Chungcheong-Namdo Province (충청남도 해안에 발달한 해빈과 해안사구)

  • Kahng, Tay-Gyoon
    • Journal of the Korean earth science society
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    • v.24 no.6
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    • pp.568-577
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    • 2003
  • The purpose of this paper is to examine the geomorphic processes of beach and sanddune development in the Chungcheong-Namdo Province. The sands consist mainly of quartz and feldspar with lesser amounts of mica and other heavy minerals. With the exception of those from the granite, the sands have a very fine texture. Another characteristic of the sand grains is low degrees of roundness and grading indicating that source areas for the material were in the vicinity of the accumulating field. Over the years, the beaches have receded as a response to the decreasing amount of depositional materials. The driving force for the formation and transformation of coastal dunes in the study area is dominant winds from the center of the Siberian High. To some extent, the erosion of coastal dunes has been a global phenomenon. The degradation process occurred most actively when spring tides attacked beaches, berms, and foredunes. The relief and shape of present-day coastal dunes is determined initially by the Pleistocene strata underneath. From the fact that the strata contained traces of frozen structure, it can be inferred that sediment once experienced the process of soil formation.

Analyzing Sand Transfer Path by Songdo Beach Using Time Series Analysis (시계열 분석을 통한 송도해안의 해안사구 이동경로 분석)

  • Han, Chung-Mok;Kim, Yong-Suk
    • The Journal of the Korea Contents Association
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    • v.9 no.8
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    • pp.384-391
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    • 2009
  • The coastline area, which was the important to decide the shape of the national land, has the characteristics of changing its shapes and features. We have some trouble to make the appropriate use-plan, because of the huge land to be reclaimed from the sea and developing large and small coast areas. Of them the coastal sand dune plays a definite primary role in the side of tourism and ecology. But there is not enough study for that. Busan Songdo coast is decided as an object of this study. We would analyze transfer path of the coastal sand dune through the time series analysis with RTK-GPS survey for many years. In case of Song do coast, the mean coastline length is approximately 620m, the area is approximately $31,846m^2$. Breakwaters are set up in right and left sides in Song do coast. it can make the sand dune be a minimum. So the coastal sand dune is steadily deposited with a certain beach nourishment of every year. As a result of 7 times survey, both sides of the coastal sand dune are eroded. It turns out it is going ahead over all as the center of the coastal sand dune is deposited.

The Irrigation and Drainage Systems of Coastal Alluvial Plain: Sand Dune Area and Allurial Plain in Bulgap River Catchment in South Jeolla Province (소규모 임해충적평야의 수리체계 -불갑천 하류의 충적지와 해안사구를 중심으로-)

  • Kahng Taygyoon
    • Journal of the Korean Geographical Society
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    • v.39 no.6 s.105
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    • pp.863-872
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    • 2004
  • The coastal alluvial plain, sand dune, tidal nat might be the most prominent coastal landscape in western coast of Korea. The purpose of this paper is to examine the irrigation and drainage systems of the alluvial plain in the tidal coast. This study is concerned on the geomorphological and cultural landscapes of the alluvial plain in the western coast of the South Jeolla Province. The alluvial deposits have developed mainly by the actions of tidal currents, rather than transporting sediments by stream. The transformation of plain has been affected by human agency since 1920's. Dwellers have constructed the reservoir, banks, dammed pools, lock gates, and tide-dykes for the reclamation, irrigation, and drainage on the alluvial plain, coastal sanddune, and tidal flats.

The Effective Wind Velocity and the Patterns of Morphological Change in the Coastal Dune Area (해안사구에서의 유효풍속과 지형변화)

  • Sea, Jong-Cheol
    • Journal of the Korean association of regional geographers
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    • v.10 no.3
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    • pp.667-681
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    • 2004
  • This research is aimed to investigate the relationship of the effective wind velocity and the morphological change in coastal dune at Sindu-ri in Korea. Sediment flux was estimated by the measurement of elevation change along eight transects deployed in the study area from July 1999 to July 2000. The results of this study indicated that. first. based on the occurrence of morphological change and winds effective for sand movement. two distinct seasons were identified: a season of deposition and that of erosion. During the depositional season, spanning from November to April, effective winds were dominant and sand accumulation occurred mainly in foredunes and sequentially in dune plains. During the erosional season, from May through October, volume change was small and erosion or sand loss occurred mostly at the dunefoot of foredunes. Secondly, the research revealed that the sediment budget of Sindu coastal dune turned out to be surplus on the whole, but there are some regional differences. Deficit budgets were observed partly in secondary dunes. The utmost northern part of Sindu coastal dune was provided with abundant sand, whereas the central and northern parts were poorly supplied.

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A Case of Type II Membranoproliferative Glomerulonephritis Detected by School Urinary Screening Tests (학교 신체검진 상 우연히 발견된 제2형 막증식성 사구체신염 1예)

  • Kim, Hyung-Joong;Kwak, Byung-Ok;Bae, Jae-Uk;Kim, Kyo-Sun;Lim, So-Dug
    • Childhood Kidney Diseases
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    • v.14 no.1
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    • pp.79-83
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    • 2010
  • Type II membranoproliferative glomerulonephritis (MPGN) is characterized by thickening of the glomerular basement membrane owing to electron-dense deposits on electron microscopy. We experienced a case of type II MPGN in a child presenting with proteinuria, hematuria on school urinary screening tests. He had been treated with losartan and enalapril. This is the first case report of type II MPGN detected by school urinary screening tests in Korea. Thus we report a case of 10-years-old male with type II MPGN with a review of brief literature.

Seasonal changes in coastal dunes and its implication, Sohwang-ri, in Chungnam Province (보령 소황리 전사구의 계절별 지형변화 특성과 그 의의)

  • JUNG, Pil Mo;CHOI, Kwang Hee;KIM, Yoonmi
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.4
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    • pp.109-122
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    • 2012
  • Topographic changes in the foredune in Sohwang-ri, Boryeong, Chungnam Province was analyzed over the last two years. Seven cross-sections and one permanent plot ($20m{\times}50m$) were periodically studied based on erosion and deposition measurement, in addition to vegetation monitoring and measurement of wind using an automatic weather station. The sand dunes usually grew from late winter to spring and the growth occurred in a period of strong northwesterly winds. From March to April, heavy sedimentation was observed on the front section of the foredune and sand piled up to ca. 30cm to the ca. 25m landward from the high tide line. It is likely that increased wind force and growth of vegetation played a major role in transportation and sedimentation of sand. Meanwhile, the lower part of the sand dunes was eroded when typhoon and spring tide caused a rise in sea level. The transition zone of beach and dune was usually affected by sea water but some frontal slopes were entirely influenced, resulting in dune scarps. The eroded scarps were naturally restored to their original state as time passed.

Determination of Appropriate Sampling Frequency and Time of Multiple Blood Sampling Dual Exponential Method with $^{99m}Tc$-DTPA for Calculating GFR (사구체여과율 계산을 위한 $^{99m}Tc$-DTPA를 이용한 다중 채혈 이중지수법의 적정 채혈 횟수 및 시간의 선정)

  • Kim, Chung-Ho;O, Joo-Hyun;Chung, Yong-An;Yoo, Ie-Ryung;Sohn, Hyung-Sun;Kim, Sung-Hoon;Chung, Soo-Kyo;Lee, Hyoung-Koo
    • Nuclear Medicine and Molecular Imaging
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    • v.40 no.1
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    • pp.33-39
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    • 2006
  • Purpose: To determine appropriate sampling frequency and time of multiple blood sampling dual exponential method with $^{99m}Tc$-DTPA for calculating glomerular filtration rate (GFR). Materials & Methods: Thirty four patients were included in this study. Three mCi of $^{99m}Tc$-DTPA was intravenously injected and blood sampling at 9 different times, 5ml each, were done. Using the radioactivity of serum, measured by gamma counter, the GFR was calculated using dual exponential method and corrected with the body surface area. Using spontaneously chosen 2 data points of serum radioactivity, 15 collections of 2-sample GFR were calculated. And 10 collections of 3-sample GFR and 12 collections of 4-sample GFR were also calculated. Using the 9-sample GFR as a reference value, degree of agreement was analyzed with Kendall's $\tau$ correlation coefficients, mean difference and standard deviation. Results: Although some of the 2-sample GFR showed high correlation coefficient, over or underestimation had evolved as the renal function change. The 10-120-240 min 3-sample GFR showed a high correlation coefficient (${\tau}=0.93$), minimal difference ($Mean{\pm}SD=-1.784{\pm}3.972$), and no over or underestimation as the renal function changed. The 4-sample GFR showed no better accuracy than the 3-sample GFR. Conclusions: In the wide spectrum of renal function, the 10-120-240 min 3-sample GFC could be the best choice for estimating the patients' renal function.