• Title/Summary/Keyword: Sea Sand

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A study of seasonal variation of the residual flow before and after Saemangeum reclamation (새만금간척 전.후 잔차류의 계절변화에 관한 연구)

  • Shin, Moon-Seup;vanagi, T.;Hong, Sung-Kun;Lee, Dong-Ju
    • Journal of Korea Water Resources Association
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    • v.35 no.4 s.129
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    • pp.425-442
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    • 2002
  • The land reclamation area of Saemangeum(Kunsan) is located between $126^{\circ}10'\;E{\sim}126^{\circ}50'\;E\;and\;35^{\circ}35'\;N{\sim}36^{\circ}05'\;N$ at the western coast of the Korean peninsula. The reclamation area of Saemangeum has a range of 5.6m spring tide and the maximum tidal current speed is about $1.41m\;s^{-1}$. In ordinary spring tide. Most of the sediments deposited on the tidal flats are transported from the Geum river, the Mankyung river and the Dongjin river. The soil in this area consists of silty sand with the depth of 10m to 30m. The wind in winter is strong from the direction of northwest. Saemangeum coastal area is being constructed 33km the sea dike and 40,100ha reclamation area. The purpose of this study Is to find the residual circulations in four seasons before and after the dike construction by a robust diagnostic and prognostic numerical model.

Distribution and Pollution of Heavy metals in Surface sediments from Nakdong River (낙동강 수계 표층 퇴적물의 중금속 분포와 오염도)

  • Kim, Shin;Kim, Jueon;Lee, Kwonchul;Lee, Kyuyeol;Jeon, Hyelyn;Yu, Jaejung;Lee, Injung;Ahn, Jungmin
    • Journal of Environmental Science International
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    • v.24 no.8
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    • pp.969-980
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    • 2015
  • In order to certificate the distribution and pollution of heavy metal of surface sediments in Nakdong River were collected and analyzed for grain size, water content, ignition loss and heavy metal content. Surface sediments mainly composed of sand(avg. 94.6%) and water content and ignition loss were 20.46%, 1.53% on average. Grain size were relatively fine and organic matter content were relatively high in the Hoichun and Sunakdonggang. Most of heavy metal content(Zn > Cr > Pb > Ni > Cu > Hg) in the Deokcheongang and Sunakdonggang were higher than the other streams. The Igeo were non polluted(less than 0) in all streams and the EF were relatively high in the small stream and PLI were non polluted(less than 1). In addition, organic matter, heavy metal content and pollution were highly correlation with grain size. Surface sediments in study area, heavy metal pollution of the Sunakdonggang were relatively high compared to the other stream but these results were not serious pollution that exceed the sediment pollution evaluation standard of river and lake in Korea and pollution levels adversely affected the majority of benthos were not.

Turbidity Meter Calibrations Based on Grain Size Distribution of Trapped Suspended Material (포획된 부유물질의 입도분포를 고려한 탁도계 검교정)

  • 조홍연;김백운
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.15 no.1
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    • pp.33-38
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    • 2003
  • Turbidity meter calibrations were conducted using bottom sediment and suspended material collected with a vertical array of sediment traps at the coastal water off Gaduk Island. Compared to the bottom sediment comprising sand fraction of approximately 6%, trapped suspended material was composed entirely of silt and clay fractions and showed a tendency to get finer as elevation from the sea-bed increases. Slope parameter of linear regression due to bottom sediment was of minimum value and values of those due to suspended material increased gradually as the height of sediment trap increases (i.e., sediment size decreases). This result shows that turbidity meter calibration using bottom sediment can cause an overestimation error in the calculation of suspended sediment concentration and that the error can reach up to 25% in case of this study. Therefore, it is suggested that the use of a corrected calibration curve based on grain size distribution of suspended material instead of bottom sediment may reduce the measurement error of suspended sediment concentration.

The morphological changes of the beach and dune using by periodical measurements (주기적 지형 측량을 통한 해빈과 해안사구의 지형변화: 충남 보령시 소황사구를 사례로)

  • KANG, Dong Kyun;SEO, Jong Cheol
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.2
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    • pp.69-79
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    • 2012
  • The aim of this study is to analyze the mid-term changes of beach and dune morphology at Sohwang beach, Korea using by Total Station. Measurements executed 4 times during two year. Based on ArcInfo as point cloud obtained through precise measurement data by Total Station, alteration of beach and dune was analyzed at DEM, of which cell size is about 1m. Since these artificial constructions have influenced current systems of this region, the large-scale sand movements above mentioned have occurred around the jetty and the sea-wall. There occurred sedimentation in the north of the Jetty and erosion in the south of the Jetty, which is installed at the central part of object area. The direction of recent topographic development does not coincide with that of wind, and, rather, topographic changes occurred mainly at beaches and dunes due to the transformation of coastal water flow caused by artificial structure nearby. If precise measurement is conducted periodically, and long term monitoring is carried out by installing equipment measuring movement pattern of sediment around artificial structure, cause of topographic change around the object area could be discovered.

A report on 53 unrecorded bacteria species in Korea in the class Gammaproteobacteria

  • Kanjanasuntree, Rungravee;Cha, Chang-Jun;Cho, Jang-Cheon;Im, Wan-Taek;Kim, Myung Kyum;Jeon, Che-Ok;Joh, Kiseong;Kim, Seung-Bum;Seong, Chi-Nam;Yi, Hana;Lee, Soon Dong;Bae, Jin-Woo;Kim, Wonyong
    • Journal of Species Research
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    • v.8 no.4
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    • pp.319-336
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    • 2019
  • During an investigation of unrecorded prokaryotic species in Republic of Korea, a total of 53 bacterial strains belonging to the class Gammaproteobacteria were isolated from soil, seawater, tidal flats, rhizosphere, salt ponds, beach sand, urine, manure, sediment, and animal intestine (Russian grayling butterfly [Hipparchia autonoe], mouse [Mus musculus], and sea bass [Lateolabrax japonicus]). Strains were identified to species using the 16S rRNA gene sequence, showing high similarity (>98.7%) with the closest bacterial species and forming a robust clade in the neighbor-joining phylogenetic tree. The 53 strains of Gammaproteobacteria in this study have not been report previously in Korea. Therefore, we describe 27 genera of 16 families in 7 orders: 13 strains in the order Alteromonadales, 1 strain in the order Chromatiales, 11 strains in the order Enterobacterales, 7 strains in the order Oceanospirillales, 10 strains in the order Pseudomonadales, 8 strains in the order Vibrionales, and 3 strains in the order Xanthomonadales. Gram reaction, strain ID, isolation source, and morphological and basic biochemical characteristics are described for each species.

Liminality & Transformative Drama in Shelley's "Julian & Maddalo"

  • Narrett, Eugene
    • English & American cultural studies
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    • v.10 no.2
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    • pp.149-207
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    • 2010
  • Written simultaneously with Prometheus Unbound, Shelley's "Julian & Maddalo" is a masterwork of dramatic poiesis, of doubling embedded in its couplets, dialogic debate on human nature and contrasted symbolic emblems. The emblems mirror each other and are themselves sites of generative paradox: the "heaven illumined" but "dreary tower" of the Maniac and the glorious sunsets on the "ever-shifting sand" of the Lido, a wasteland that is a place of self discovery but also of "abandonment" and barren mingling figured, inter alia, in its "amphibious weeds," a trope of the poem's personae. This essay also explores the poem's dramatic structure and various rhetorical devices, beginning with the Preface, a threshold of complex identity disguise that Shelley uses for veiled self-presentation, as in "Alastor," mirroring and literary references replete with nuanced ironies. I focus mainly on the complex figures of liminality Shelley uses to develop his own thoughts (as well as his ongoing debates with Byron) about man's potential for growth in thought, insight and empathy, in political reform and interpersonal and individual healing. Advancing Shelley's most optimistic ideas, Julian, escorted by Maddalo observes the Maniac, -- a living ruin whose pained eloquence reveals the link of eros to poiesis and the limits of the latter's ability to 'transform a world.' The Maniac is the core of muse-work (remembering, thinking and song) and Shelley presents him as its emblem. He also is prefigured in and reflects the quintessentially liminal Lido with its "barren embrace" of sea and land. Yet it is less the Maniac's feeling that his grief is "charactered in vain…on this unfeeling leaf" than Julian's rationales for leaving the site of pain that point to Shelley's final comment on poetry's transformative limits. As the primary haploids of the drama's meiosis re-combine and two of them, Maddalo and the maniac fall away, an analogy I briefly develop and embedded in the erotic dynamics of poiesis, Shelley suggests, as he did at the beginning of his poetic lyricism in "Alastor" and at its end in "the Triumph of Life"that images mislead and delude; that "the deep truth is imageless" and redemption is not in but beyond figuration.

Suction Penetration Review of Circular Steel Pipes by Field Test (현장 실험을 통한 원형강관 석션관입성 검토)

  • Kim, Hyun-Joo;Choi, Jin-O
    • Journal of the Korean Geotechnical Society
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    • v.36 no.12
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    • pp.35-43
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    • 2020
  • Currently, cofferdams of circular cross section are widely applied as temporary facilities for the installation of bridge foundations in river/sea bridge construction in Korea. Existing caisson, sheet pile, and cell type cofferdam are widely used, but these methods take a lot of time and cost for installation and dismantling. In the case of the existing sheet pile construction method, attention is needed to secure internal and external stability because of the damage to the sheet pile due to ground penetration and difficulty in connecting element members. In this study, penetration design of circular steel pipes using suction pressure was performed on the soft ground of the west coast, and it was confirmed that penetration construction using suction pressure was possible through field tests. It was confirmed that applying the ground analysis results using the cone penetration test (CPT) to the design rather than the standard penetration test (N value) results more similar to the field test results. In addition, it was confirmed that local failure of the inside of the cofferdam was induced when a suction pressure higher than the upper limit suction pressure was applied in the silty sand.

A report of 24 unrecorded bacterial species in Korea belonging to the Phyla Proteobacteria and Bacteroidetes isolated in 2020

  • Kim, Ju-Young;Yoon, Jung-Hoon;Joh, Kiseong;Seong, Chi-Nam;Kim, Won-Yong;Im, Wan-Taek;Cha, Chang-Jun;Kim, Seung-Bum;Jeon, Che-Ok;Seo, Taegun;Kim, Myung Kyum
    • Journal of Species Research
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    • v.11 no.3
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    • pp.133-142
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    • 2022
  • In 2020, 24 bacterial strains were isolated from algae, kudzu leaf, mud, pine cone, seashore sand, sea water, soil, tidal flat, and wetland from the Republic of Korea. Isolated bacterial strains were identified based on 16S rRNA gene sequences, and those exhibiting at least 98.7% sequence similarity with known bacterial species, but not reported in Korea, were highlighted as unrecorded species. These isolates were allocated to the phyla Bacteroidetes and Proteobacteria as unrecorded species in Korea. The four Bacteroidetes strains were classified into the families Chitinophagaceae, Flavobacteriaceae, and Sphingobacteriaceae (of the orders Chitinophagales, Flavobacteriales, and Sphingobacteriales, respectively). The 20 Proteobacteria strains belonged to the Aeromonadaceae, Marinobacter, Microbulbiferaceae, Enterobacteriaceae, Erwiniaceae, Morganellaceae, Yersiniaceae, Lysobacteraceae, Halomonadaceae, Moraxellaceae, Pseudomonadaceae, Steroidobacteraceae, Xanthomonadaceae, and Myxococcaceae (of the orders Aeromonadales, Alteromonadales, Cellvibrionales, Enterobacterales, Lysobacterales, Oceanospirillales, Pseudomonadales, Steroidobacter, Xanthomonadales, and Myxococcales). This study focused on the description of 24 unreported bacterial species in Korea in the phyla Bacteroidetes and Proteobacteria belonging to six classes.

Time Series Coastline Change Analysis of Haeundae Beach (해운대 해안의 시기별 해안선 변화량 분석)

  • Lee, Jae One;Kim, Yong Suk;Lee, In Soo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.5D
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    • pp.655-662
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    • 2009
  • The monitoring for analyzing coastline variations throughout many years is conducted in this study. Haeundae Beach is selected as a test area. We have collected RTK-GPS survey data, airborne LiDAR survey data from Sept. 2008 to 2005. We've done airborne LiDAR survey 2009 to 2006 and we would analyze coastline changes time series through interactive comparison analysis. The mean coastline distance of Haeundae shore is 1,347m (RTK-GPS) by airborne LiDAR survey (2 times). Coastline distance is decreased approximately 4.5% than mean distance in the November survey of 2008. We know right and left sides of the coastline are eroded and the center section shows us the littoral deposit of 3~7m toward sea. It turns out that the sand both sides is transported to the center section by a wave and tide and we know the coastline distance is getting smaller but the coastline width is getting longer like 2~7m.

Newly Recorded Diatoms from the Tidal Flats of Korea (갯벌 조간대에서 발견한 국내 미기록 규조류)

  • BYOUNGSEOK KIM;SOYEON KIM;JEONGYUNG JIN;BYEOL KIM;JONG-GYU PARK
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.29 no.1
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    • pp.42-55
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    • 2024
  • To discover unrecorded diatoms, seawater, sand, and pebbles were collected from the intertidal zone of five tidal flats from 2016 to 2023. Diatoms were isolated from the collected samples, cultured, and the ultrastructure of the cells was observed using a scanning electron microscope. 7 species of unrecorded diatoms, consisting of 3 orders, 5 families, and 7 genera, were discovered: Gomphoseptatum aestuarii, Rhoiconeis pagoensis, Seminavis exigua, Plagiolemma distortum, Staurotropis seychellensis, Biremis sigmoidea, Liriogramma sarcophagus. Among these, four genera, Rhoiconeis, Plagiolemma, Staurotropis, and Liriogramma, are reported for the first time in Korea. L. sarcophagus was separated from the central diatom Asteromphalus and transferred to Liriogramma, but its phylogenetic position has not yet been clearly established.