• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.505-509
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• 2002

남해 중부해역에서 적조발생과 관련해서 적조 다발월인 여름과 초가을에 기온과 마찬가지로 높은 수온을 유지한다. 또한 많은 강수량에 의하여 부유물질 및 영양염류가 증가하고 염분이 대체로 떨어지는 것을 알 수 있었다. 이때 적조의 bloom으로 인하여 대표적인 영양염류인 질소와 인의 값이 떨어진다. 그리고 적조생물의 사후 미생물 분해 작용이 활발하여 산소의 소모가 증가하여 용존산소가 급격히 떨어지고 화학적산소요구량이 높게 나타나는 것을 알 수 있었다. 즉, 해양인자와의 상관성은 적조의 발생조건인 수온이 적당하며 저염분과 부유물질, 클로로필, 질소, 인이 높게 나타났고 용존산소는 적조생물의 인해 낮게 나타났음을 알수 있었다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.05a
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• pp.22-27
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• 1994

6종류의 유연탄을 대상으로 석탄회분의 용융온도와 화학적조성을 측정하고, 대상탄 회분에 대해 Rs 값과 Fs 값을 계산해 봄으로써 각 탄들의 Slagging 성향을 알아보았다. 그리고, 이 자료만으로는 정확한 Slagging 성향의 예측이 어려우므로 분류층 가스화기의 조건을 모사한 DTF(Drop Tube Furnace : 이하 DTF)장치를 이용하여 온도와 체류시간을 달리하면서 생성되는 Slag의 화학적조성, 강도, 점착속도 등을 측정하여 Slagging 형태의 가스화기 운전에 있어서 최적조건을 제시하고자 한다.

• Food Industry
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• s.41
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• pp.17-22
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• 1977

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1995.06a
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• pp.267-270
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• 1995

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.4
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• pp.938-945
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• 2004

On the relationship between the red tide occurrence and the oceanographic factors in the middle coastal area in the South Sea of Korea, the favorable oceanographic conditions for the red tide formation are considered as follows； the calm weather increases sea water temperature in summer and early-fall which the red tide occurs frequently, and the heavy precipitation brings some riverine water to ween: low salinity, high suspended solid, low phosphorus and high nitrogen, respectively. We decided the potential areas in the coastal zones vulnerable to the red tide occurrence based on the limited factors controlling the growth of phytoplankton. By using GIS through the overlap for three subject figures (phosphorus, nitrogen and suspended solids), it was founded that the potential areas are the Yeosu∼Dolsan coast, the Gamak bay, the Namhae coast, the Narodo coast, the Goheung and Deukryang bay. This result has very well coincided to the results of the satellite and in-situ data.

• 한국생활과학회:학술대회논문집
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• 2009.05a
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• pp.143-144
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• 2009

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.12B
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• pp.1219-1226
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• 2010

It is necessary to implementation of system contain intelligent decision making algorithm because discriminant and prediction system for Red Tide is insufficient development and the study of red tide are focused for the investigation of chemical and biological causing. In this paper, we designed inference system using case based reasoning method and implemented knowledge base that case for Red Tide. We used K-Nearest Neighbor algorithm for recommend best similar case and input 375 EA by case for Red Tide case base. As a result, conducted 10-fold cross verification for minimal impact from learning data and acquired confidence, we obtained about 84.2% average accuracy for Red Tide case and the best performance results in case by number of similarity classification k is 5. And, we implemented Red Tide monitoring system using inference result.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.557-561
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• 2003

It is important to find out a new material having high removal efficiency for the harmful algal blooms because the dispersion of Hwangto in a large amount to the sea water may bring some ecologically unfavorable problems. For this purpose, the efficiency of several natural and synthetic mineral species for the mitigation of algal blooms was measured. The mixing ratio of monominerals and the sea water with 3,000∼5,000 cells/$m\ell$ of Cochlodinium polykrikoides was 10 g/${\ell}$ and the removal ratio was measured by counting the living cells after the dispersion time of 10, 30 and 60 min., respectively. According to the experimental results, the removal ratio by illite, kaolinite, montmonmorillonite, red mud, Na-A type of zeolite ranged 84-92% after 1hr of contact time, which is comparable to that of Hwangto. The size of above monominerals ranged 3∼50${\mu}m$. Meanwhile, the amorphose material and hematite with the size of 50∼100 nm showed excellent removal ratio of more than 99% after 30min. of dispersion. The results of the study showed that the removal ratio was not related to the chemical composition and pH of the minerals applied but to the grain size. The experimental results strongly suggest that the main mitigation mechanism would be the contact and coagulation.

• Korean Journal of Ecology and Environment
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• v.36 no.3 s.104
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• pp.235-241
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• 2003

The effect of ultraviolet (UV) radiation on the characteristics of algae-derived dissolved organic matter (DOM) was examined by comparing the biodegradability and DOM fraction distribution of algal DOM before and after UV exposure. Algal DOM from two axenic cultures of Microcystis aeruginosa and Oscillatoria agardhii were irradiated for 24 h at a UV intensity of 42 W/$m^2$. A complete degradation of algal DOM during the UV exposure did not occur, remaining at constant concentrations of dissolved organic carbon(DOC). After UV exposure, however, microbial degradations were reduced by 17% in M. aeruginosa and 53% in O. agardhii, respectively, and decomposition rates also were two times lower in UV exposed algal DOM. In addition, the chemical compositions of algal DOM altered substantially after UV radiation exposure. The proportions of hydrophilic bases (HiB; protein-like DOM) decreased considerably in both algal DOM sources after UV exposure (16.8% and 20.0% of DOM, respectively), whereas those of hydrophilic acids (HiA; carboxylic acids-like DOM) increased as much as the decrease of the HiB fraction. Capillary ion electrophoresis (CE) analysis showed that several carboxylic acids increased significantly after UV exposure, further confirming an increase in HiA fractions. The results of this study clearly indicate that algal DOM can be changed in its chemical composition as well as biodegradability without complete degradation by UV radiation.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.2
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• pp.49-62
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• 2001

Hydrographic surveys were carried out seven times during May 31, 1998 and September 24, 1998 in order to study the physical environments of the coastal area between Narodo Is. and Sorido Is. in the southern sea of Korea (the South Sea) where the occurrence of Cochlodinium polykrikoides red tide is frequently observed in summer. Temperature and salinity of the water column from the surface to the depth of 30 m exhibit large seasonal variations. Mean temperature of the water column increased by 6 and mean salinity of the water column decreased by 2.71 psu during the observation period. Both the freshwater supplied from the adjacent land and the precipitation over the study area cannot account for the observed salinity variations. The influx of the low salinity water from the offshore area is considered to be the main cause for the observed salinity changes. Surface salinity in the study area shows different spatial distribution in the period of outbreaking, mid-stage and disappearance of the red tide. Especially, salinity was abruptly lowered at the stage of disappearance of red tide as compared to salinity of the previous observation period. Vertical structure of water properties also became vertically homogeneous at the disappearance stage, while it was highly stratified in the previous observation. Such changes can only be explained by the inflow of low salinity water from the offshore, which is considered as the most possible cause for the disappearance of the red tide in the study area. This study suggests that exchanges of water, and chemical and biological factors between coastal areas and of shore area in the South Sea need to be studied in association with the general circulation of the South Sea in order for the better understanding of the occurrence and disappearance of the red tide in the coastal area of the South Sea.