• Title/Summary/Keyword: 하구배

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The Early-Stage Changes of Water Qualities after the Saemangeum Sea-dike Construction (새만금 방조제 체절 이후 초기의 수질변화에 관한 연구)

  • Yang, Jae-Sam;Jeong, Yong-Hoon;Ji, Kwang-Hee;Kim, Hyun-Soo;Choi, Joeng-Hoon;Kim, Won-Jang
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.11 no.4
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    • pp.199-213
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    • 2008
  • Saemangeum salt-water Lake has been created by the completion of the sea-dike in April 2006. To monitor the water qualities of the lake during the sea-dike construction, salinity, SS, nutrients(DIN, DIP, DISi), and chlorophyll-$\alpha$ was analyzed for the surface water from 1999 to 2007. Due to the dike construction, weaker tidal current and lesser resuspension of bottom sediment resulted in the marked decrease of the concentrations of SS in the lake water. Consequently the clearer lake water has provided better condition for primary production with deeper penetration of sunlight into the water column and sufficient nutrient content in the water. Finally the chlorophyll-$\alpha$ content became approximately double in the concentration after the dike construction. Highly stimulated algal production with the marked decrease of the concentrations of SS was decreased the concentration of DIP in the surface water. On the other hand the concentration of DIN and DISi in surface water was increased after dike construction due to the expansion of the freshwater and the supply from bottom layer. As a result, the lake revealed an extremely high NIP ratio and a DIP-limited ecosystem. The lake has been transformed from a typical coastal ecosystem to a brackish one. Since the dike completion, the lake has shown a similar change pattern to the Geum River estuary. Due to the salt-wedge intrusion of seawater, it is highly probable to expect the formation of low-oxygen zone at the bottom layer near the river-mouth area of the lake during the summer. Therefore we need a continuous sentinel monitoring of bottom water qualities in the near future.

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Limiting Nutrient on Phytoplankton Growth in Gwangyang Bay (광양만에서 식물플랑크톤증식의 제한영양염)

  • Lee, Jae-Seong;Jung, Rae-Hong;Kim, Soung-Soo;Go, Woo-Jin;Kim, Kui-Young;Park, Jong-Soo;Lee, Young-Sik
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.3
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    • pp.201-210
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    • 2001
  • Salinity, DIN, DIP, DIN/DIP and indigenous algal assay were determined to estimate the limiting nutrient for phytoplankton growth in Gwangyang Bay, South Sea of Korea. Seawater samples were collected at surface and bot-tom water in 4 November 1999 (dry season) and 2 September 2000 (after heavy rain). In 4 November 1999, the salinity, DIN, DIP and DIN/DIP were 29.92 psu, 13.59 ${\mu}M$, 3.41 ${\mu}M$ and 4.14 respectively. In 2 September 2000, These values were 24.62 psu, 27.77 ${\mu}M$, 2.82 ${\mu}M$ and 9.79 respectively. The DIN and DIP concentrations in this study were higher than Deukryang, Yeoja and Gamak Bay, South Sea of Korea. Especially, DIP concentration was 8 times high compared to Deutryang, Yeoja and Gamak Bay. The main sources of nitrogen seem to be freshwater runoff from Somjin River and industrial wastewater. But, the main sources of phosphorus seem to be industrial wastewater around Gwangyang Bay. The limiting nutrient was nitrogen at all station in 4 November 1999. The limiting nutrient was also nitrogen in 2 September 2000 in spite of heavy rain observed because of relatively much volume of phosphorus sup-plied from point sources than nitrogen. In case of below 20 psu in salinity by heavy rain, the limiting nutrient willbe shift from nitrogen to phosphorus at some area of Somjin River estuary. But the limiting nutrient will be never shift to phosphorus throughout Gwangyang Bay, eastern coast of Yeoja and Dolsan because of much volume of phosphorus runoff from point source in coastal area of Gwangyang Bay.

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Pollution of Heavy Metals and Sedimentation Rate in the Sediments of Suyeong Bay, Pusan (수영만 퇴적물의 퇴적속도와 중금속 오염)

  • YANG Han-Soeb;KIM Seong-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.27 no.5
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    • pp.643-658
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    • 1994
  • The sedimentary records of anthropogenic metal loads in the Suyeong Bay, Pusan were determined by combining the Pb-210 dating technique with the measurements of heavy metals in the sediment cores. The sedimentation rates of sediment particles ranged from $0.12\;to\;0.20\;g/m^2/yr\;or\;2.4{\sim}4.0\;mm/yr$ in accumulation rates. The lowest sedimentation rate was observed at station S3 which was characterized by a bottom with relatively low organic matter contents(e.g. TIL and TOC). Heavy metals showed generally higher concentrations at station S1 and S2 near the mouth of the Suyeong River than at station S3 and the outmost station S4. The contents of copper, lead and zinc in the sediment cores especially from station S1 and S2 began to increase around 1930, and were at their highest levels in the $1960{\sim}1970$ period as a result of increasing industrial activities. Concentrations of these heavy metals have slightly decreased since 1970, probably due to regulation of pollution discharge. The natural background levels of copper, lead and zinc in the sediments of this bay ranged $18{\pm}4ppm,\;28{\pm}6ppm\;and\;74{\pm}9ppm$, respectively, by averaging the contents in the sediment depths corresponding to periods between about 1900 and 1920 at the four stations. The total amounts of anthropogenic loads deposited in the sediments since about 1930 were estimated to be $9{\sim}291{mu}g/cm^2$ for lead, $165{\sim}1122{mu}g/cm^2$ for zinc and $20{\sim}208{mu}g/cm^2$ for copper. These values were remarkably high at stations S1 and S2 relative to the other two stations. At stations S1 and S2, the anthropogenic loads of lead, copper and zinc constituted $29{\sim}30\%,\;32{\sim}42\%\;and\;28{\sim}35\%$ of the total sedimentary inventories at the present day, respectively. These metal contents have a good correlation(r>0.7) with each other and cadmium measurements also show a positive linear relation with nickel or total organic nitrogen.

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Resilience of Cultural Heritage by Integrating Historic Maps and Geospatial Information (고지도와 시계열 공간정보를 활용한 문화재 리질리언스에 대한 연구)

  • Bae, Junsu;Yang, Yunjung;Choi, Yoonjo;Kim, Sangkyun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.39 no.6
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    • pp.945-954
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    • 2019
  • Cultural property is a valuable asset that connects the past with the present, and cultural heritage is now included in the international agenda of disaster risk reduction. Accordingly, the importance of building resilience of cultural assets has been on the rise, and the necessity of spatial information has been emphasized in building resilience. Therefore, in this study, A methodology for studying the resilience contained in cultural assets through linkage with historical map and time series spatial information is proposed and the proposed methodology was applied to cultural assets located in Gongju area. Georeferencing was performed on time-series images of aerial images and topographical map, and the changes in cultural assets and surrounding areas were found. The width of the river has changed due to the installation of the Keum River Estuary Dam and the dammed pool for irrigation. Nevertheless, the main cultural assets and monuments are located in the high-altitude area and thus have been well preserved. In this study, cultural property resilience was extracted using only map data and in future, it is necessary to conduct research to extract cultural property resilience through analysis of historical records such as geography.

The Distribution of phosphorus in the Gomso Bay Tidal Flat (곰소만 조간대에서 인의 시공간적 분포)

  • 양재삼;김영태
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.7 no.3
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    • pp.171-180
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    • 2002
  • The temporal and spatial distributions of phosphorus have been investigated in the Gomso Bay, Korea. TP, PIP, TOP and DIP in sediment were found 548.8mg P kg$^{-1}$ , 426.1mg P kg$^{-1}$ , 122.6mg P kg$^{-1}$ , and 0.217mg P kg$^{-1}$ , respectively with a decreasing order of PIP>TOP>DIP. Any temporal or spatial trend has not been found on the distribution of TP in the sediment, except the high TP values near the mouth of Julpo-chun. We found seasonal patterns high TOP(28.90% of TP) and low TIP(71.10% of TP) in August, but low TOP(15.63% of TP) and high TIP(84.38% of TP) in November. There were three times higher DIP concentration in August than in November. Such case is probably not only due to the enhanced supply of DIP directly from the decomposition of organic matter from overlying water in summer, but also the released phosphate from the adsorbed particulate matter such as PIP under the low pH and Eh conditions at the subsurface layers of the sediment induced by the active microbial respiration of increased organic materials in summer. Primarily, the source of phosphorous from municipal sewage strongly influenced the early stage of the distribution of all the phosphorous in the Gomso tidal flat. Notwithstanding, through the processes of diagenesis in sediment, water temperature and organic contents probably functioned as the key parameters to control the temporal distributions of TOP, TIP and DIP in the Gomso tidal flat.

냉면소스 제조공정의 표준화를 통한 품질향상 연구

  • 김창임
    • Proceedings of the Korean Journal of Food and Nutrition Conference
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    • 2003.07a
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    • pp.79-79
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    • 2003
  • 최근 소득수준의 향상과 여성의 사회진출로 인해 우리의 식생활도 많은 부분이 사회화되고 있다. 즉 완전조리식품과 반조리식품이 급격히 증가하고 있다. 기존의 인스탄트식품이 저가격, 반건강 특성으로 생각되어진 반면 최근 고가의 건강 지향적인 반조리식품으로 변화하고 있다. 이러한 경향은 식품가공기술 및 식품포장기술의 향상과 사회적요구에 부합된 결과로 사료된다. 이에 대표적인 경우가 다양한 소스류의 상품화 경향이다. 본 연구개발 사업에서 이루어지는 냉면소스도 가정에서 하기에는 번거롭고, 건강지향적 식생활로 메밀의 수효가 증가하여 냉면의 소비가 증가하리라 생각된다. 현재 시판되고 있는 기존의 몇몇의 제품들이 있기는 하나 제조공정, 보존상태 등에서 많은 문제점이 있다. 따라서 문헌 통하여 기존제품의 배합비를 조사하고, 냉면소스 배합비의 최적화를 위해 10여차례에 걸쳐 20종류의 소스에 대하여 배합비의 변화와 관능검사에 의해 배주스, 양파, 겨자, 마늘, 설탕, 물엿, 소금, 미원, 참기름, 고춧가루, 진간장, 생강즙, 식초, 파인애플로 구성된 소스를 개발하였다. 개발된 소스의 pH, 당도, 염도, 색차를 측정하여 관능검사의 결과와 비교 검토하였고, 식품재료의 차이에 의한 맛의 변화를 보정하기 위한 근거로 사용하였다. 저장성 검사를 위해 일반세균과 대장균을 검사하였다. 그 결과는 다음과 같다. 소비자들의 기호에 맞는 냉면소스를 개발하기 위해 다양한 식품의 배합을 시도하여 상품성이 있을 것으로 판단되는 recipe를 완성하였고, 일반인(주부)들을 상대로 한 호감도 조사에서도 좋은 성적을 나타내었다. 시료를 1주간격으로 한달간 실험한 결과 쇠고기가 들어 있는 제품을 제외하구 대장균은 검출되지 않았으며 일반세균은 위생법의 허용치내에 있었다. 쇠고기가 있는 제품은 가격상승과 저장성에 문제가 있어 이를 제하고 최종적인 레시피를 결정하였다.있었다. 그러나 식이 섭취상태와의 관련성은 나타나지 않았다. 이상에서 생활습관이 신체계측치 및 혈중 지질 농도와 일부 상관을 보이는 것을 알 수 있었으며, 건강위험 요인도 관찰할 수 있었다. 고지혈증은 심혈관계질환의 주요한 위험 인자로 알려져 있으며, 그 유발 요인에는 여러 환경적인 요인과 식이 요인이 있다. 또한 생활습관은 영양소의 섭취량에도 영향을준다. 이처럼 식이 요인과 생활습관은 단독 혹은 상호 영향을 주게 되므로 고지혈증 및 심혈관계질환을 개선하려면 식사요법과 생활습관 교정을 병행하여야 한다. 고지혈증의 원인 중의 하나로 지적되고 있는 음주와 흡연은 상호 유도작용이 있으므로 금연이나 절주를 하고자 할 경우 두가지를 동시에 자제해야 효과적일 것으로 생각된다. 폐경후 여성들에게 발생 빈도가 높은 심혈관질환의 위험요인인 고지혈증을 예방하고자 하는 노력은 폐경후 여성들의 삶의 질적 향상을 위해서도 매우 중요하다. 또한 균형식 섭취와 운동을 통해 혈중 지질 수준을 건강하게 유지하고, 비만으로의 이행을 방지함으로써 심혈관계질환을 예방하도록 하여야겠다.료보다 절반이하 수준이었다. Ferric citrate는 차이가 거의 없었으며 ferrous lactate는 70%수준이었다. 이상의 결과에서 철분강화우유에 사용하기 적합한 철분염은 ferrous lactate, ferric citrate였는데 특히 ferrous lactate는 제품의 이화학적 품질, 생이용성 측면 모두에서 가장 좋은 것으로 나타났다.다 높았으며, 1회당 평균 8.1$\pm$5.1개의 난포란을 회수하였다. investigation can be separated into sampling and analytical uncertainties, it can be used as a criterion where the resources for the inves

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A Study on Paralytic Shellfish Poison of Sea Mussel, Mytilus edulis -Food Poisoning Accident in Gamchun Bay, Pusan, Korea, 1986- (진주담치의 마비성독에 관한 연구 -1986년 부산 감천만 중독사고를 중심으로-)

  • CHANG Dong-Suck;SHIN Il-Shik;PYEUN Jae-Hyeung;PARK Yeung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.20 no.4
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    • pp.293-299
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    • 1987
  • At various times and places all over the world men have become ill and some have died after eating shellfish that were intoxicated with paralytic shellfish poison(PSP) caused by Protogonyaulax spp. In late March, 1986, two persons were dead by ingesting wild sea mussels, Mytilur edulis, grown at bottom of an anchored waste ship to be dismantled at Gamchun Bay, Pusan, Korea. The samples were collected from the bottom of the ship during April $1\~April$ 8 of the year to find the cause of the food poisoning accident. The toxicity was estimated by bioassay with ICR male mouse, while the toxins were extracted and characterized. The toxins were extracted with acidified $80\%$ ethanol. The extract was defatted three times with dichloromethane, treated with activated charcoal, and then purified by chromatography on Bio-Gel P-2 and Bio-Rex 70. The toxic fractions obtained were analysed by cellulose acetate membrane electrophoresis, thin layer chromatography and high performance liquid chromatogaphy. The range and the average of PSP-toxicity of the samples were $132\~295\;MU/g$, 203 MU/g respectively. The amount of PSP was $26.4\~58.9{\mu}g/g$ of whole meat in range and $40.6{\mu}g/g$ in average. The toxicity of the digestive gland of the samples was 9 times higher than that of edible meat (except digestive gland) as $439\~979MU/g$, and it was about $70\%$ in total toxin. The compositional analytical results of the paralytic shellfish toxin, Gonyautoxin $1\~4$ were the major part of the PSP and Saxitoxin and neosaxitoxin were detected as the minor component. It was concluded that the food poisoning accident was caused not by Saxitoxins but by Gonyautoxins.

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Studies on a Trematode Parasitic in Bivalves III. On a New Gymnophallid cercaria, Cercaria tapes n. sp., (Trematoda) from a short-necked clam, Tapes philippinarum (조개류에 기생하는 흡충유에 관한 연구 III. 바지락 Tapes philipinarum에 기생한 Gymnophallid cercaria의 1 신종, Cercaria tapes n. sp.에 대하여)

  • KIM Young Gill;CHUN Seh Kyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.16 no.2
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    • pp.154-159
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    • 1983
  • A Gymnophallid cercaria was found in the gonadal tissue of Tapes philippinarum, and was described as a new species, Cercaria tapes n. sp. The host clams were collected from the intertidal zone of Seo-myon, Seo-chon gun, Korea from September 1980 to August 1981. The size of sporocysts was $380-650{\times}130-160{\mu}m$. The anterior part of the cercaria bears a subterminal opening and pharynx. The sporocyst bears ca. 30 cercariae and germ balls. The cercaria is elliptical in shape. The dimension of body is $160-187{\times}62-77{\mu}m$. the tail stem is $47-52{\times}17{\mu}m$, and the tail furcae is $67-72{\times}12-15{\mu}m$. Excretory bladder is Y-shaped, and the flame cell formula is 2(1)+(1)=4. The infection rate of the cercaria to the host clam was $2.01\%$ (42 infected/2,086 short-necked clams observed). The highest infection rate ($5.74\%$) was found in March, and the lowest one ($0.4\%$) observed in January. No infection was detected in May and June. The infection rates varied with the size of the short-necked clam. It was the clams of host of 2.1-3.0 cm, 3.1-4.0 cm and 4.1-5.0 cm in shell length are $0.38\%,\;15.3\%$ and $0.09\%$ respectively. The cercaria was not observed in the specimens smaller than 2.0 cm in shell length.

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Synthesis and Effect of Plasma Treatment of Acrylic Composite Particle Binder (아크릴계 복합입자 바인더의 제조와 플라즈마 처리영향)

  • Sim, Dong-Hyun;Seul, Soo-Duk
    • Polymer(Korea)
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    • v.32 no.3
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    • pp.276-283
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    • 2008
  • Kind of monomer(MMA, EA, BA, St)and the monomer ratio(80/20 to 20/80) where changed in the preparation of the core shell binder, and property was improved the plasma processing. Each material changed by plasma treatment time($1{\sim}10\;s$) to change to measure the tensile strength, contact angle and adhesion peel strength for the core shell binder optimal conditions for handling the output of the surface treatment. The type of polymerization and composition of the binder is a regardless initiator of APS, the reaction temperature of $85^{\circ}C$ to 0.3 wt% of the surfactant used to indicate when the conversion rate was the highest, core shell composite particle binder got two glass temperature curves. Core shell binder after the plasma processing contact angle change is the PEA/PSt 38 percent of cases within five seconds to indicate slight decrease was a decline rapidly if not handled $0^{\circ}$ to reach. Tensile strength PSt/PMMA varies $46.71{\sim}46.27\;kg_f$/2.5 cm and adhesion strength PEA/PMMA varies $7.89{\sim}14.44\;kg_f$/2.5 cm increases. Overall, adhesion strength of core shell composite particle is in the order of order PEA>PBA>PSt for shell monomer MMA.

Studies on parasitic trematodes in bivalves -Variation of infection rate of Cercaria tapidis and Cercaria harengulae- (조개류에 기생하는 흡충류에 관한 연구 - Cercaria tapidis, Cercaria harengulae 의 기생율 변동)

  • Kim, Young-Gill;Lee, Keun-Kwang;Kim, Young-Jin
    • Journal of fish pathology
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    • v.8 no.1
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    • pp.23-30
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    • 1995
  • We had reported the infection rates of trematode larvae, Cercaria tapidis and C. harengulae in the gonad tissues of Tapes philippinarum and Solen strictus in the estuary of Kum river, the west coast in Korea in 1980~1982. At the same sites from January 1994 to January 1995, we investigated the variation of the infection rates of these trematode larvae in the two clams. The results are follows. The infection rate of C. tapidis parasitized in T. philippinarum increased in 2.4 times (14.0%) higher than that (5.7%) in 1981. Monthly maxium infection rate was 32.0% in October 1994. Comparing the rate (23.3%) in December 1981, the rate in 1994 showed a higher trend than that in 1981. The mean infection rate of C. harengulae in T. philippinarum showed 2.3% in 1994. Comparing that (5%) in 1980, it showed a decreased rate than that in 1980. And monthly maximum infection infection rate of this clam was 6.7% in May 1994, compared with the rate (19.0%) in March 1980. It appeared furthermore decreased rate in 1994. The mean infection rate of the year of C. harengulae in S. strictus was 6.9% in 1994, while it was 10.2% between 1981 and 1982. It showed a decreased trend in 1994. Monthly maximum infection rate was 23.4% in August 1981, while it was 13.3% in April 1994. It showed a decreased trend in 1994 also. In case of C. tapidis the more large sizes of shell length the more infection rates were higher as same in the investigation in 1980, while in C. harengulae the smaller sizes, the more infection rates showed a higher trend.

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