• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.5
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• pp.353-361
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• 2015

The area of red tides occurences, which brings enormous damages every year, have been expanded to the coastal waters across the nation. Regarding to this trend, the development of red tide detection technology by using the GOCI (Geostationary Ocean Color Imager) of COMS lauched in 2010 has been drawn attentions of researchers. This study purposed on analyzing the frequency and density of red tides occurence by using the GOCI for detecting the southern sea, whereas targeted area. The observation has brought over the last three years (2012, 2013, and 2014) before the analysis was conducted. Followingly, the study could be resulted in extracting and revealing the hot spots of the red tides from two of analysis in the overlay and density. The distribution patterns of red tide occurrences according to those observed years has been shown in irregular characteristics and various changes. However, the analysis of hot spots, based on the frequency of the red tide occurrence, has revealed that the frequency of red tide occurences is continuously increased in the specific sea area. Therefore, it is concluded in that the continuous monitoring can contribute to predict accurate movements of red tides, so as establish systematic plans for preventing disasters.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.3
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• pp.257-266
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• 2007

The research on red tide is generally in progress through field work, such as the naked eye and sampling. It was difficult to forecast exactly the course, from appearance of red tide to disappearance. with the established ways of investigation and analysis. Accordingly it is need to analyze environmental factors in time and space, the appearance of red tide and the path of its migration by more objective and scientific methods. In this study, GIS is applied to analyse the space character of red tide and the interpolation of IDW(Inverse Distance Weight) is applied to assume the density distribution of red tide after gather data by using Arc/Info. After IDW interpolation, the sea area occurred over 1,000 cells/ml of red tide density is extracted with CON and SUM Function of Grid Module, and the density of the sea area is accumulated daily. As a result of this study, the distribution condition of red tide is found timely and spacially by applying GIS to the sea area of red tide, the results indicated that the spatial density and the cumulative frequency about the origin of red tide using GIS, the sea area demonstrated that the maximum density and the maximum frequency varied significantly over the Nammyun of Namhae-Is. with the maximum frequency being 49 times. accordingly if data about the areas of red tide will occur from the present are accumulated, the shifting route of red tide occurrence and extinction can be predicted.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.2 s.40
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• pp.51-57
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• 2007

Few researches related to the spatial determination of areas where red tide occurs have been performed, so accurately determining the area where red tide occurs and disappears poses difficulties. Therefore, a more objective and scientific method is necessary to analyze the occurrence and movement of red tide based on a geo-spatial information system. In this study, the coastline was extracted using a digital topographic map in order to examine areas where red tide occurs each year. An analysis of red tide occurrence areas, which were determined based on red tide data for the last several years, showed that only Yeoja bay had almost a zero case of red tide of the areas studied, whereas Dolsando in the South Sea and NamHaedo Aenggang bay areas exhibited the highest frequency of red tide occurrences. Based on these results, by using a system that determines the geo-spatial distribution status of areas repeatedly hit by red tide every year, it would be possible to predict the course of red tide and prevent consequent damages.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.145-145
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• 2020

가뭄은 과거부터 현재까지 국내뿐만 아니라 국외에서도 지속적으로 발생하고 있으며 가뭄피해를 줄이기 위하여 많은 연구가 과거에 수행되었고 현재까지도 진행되고 있다.(강동호 외 2명, 2019명) 가뭄은 일반적으로 강수량의 부족이 원인이 되어 나타나며 홍수와 달리 장기간에 걸쳐 광범위한 지역에 피해가 나타나는 특징이 있다. 그렇기에 가뭄은 감시 및 예측에 대한 어려움이 존재하며 우리나라에서도 가뭄으로 인해 수자원 공급 긴장상태를 경험하는 빈도가 점차 증가하고 있는 추세이다.(유지영 외 3명, 2016) 적조현상은 특정 조류의 폭발적인 증식으로 해수가 붉은 빛을 띄며 용존산소량을 부족하게 만들어 해양 생태계를 파괴하는 현상이다. 적조현상은 1990년대 이후 대규모 적조가 발생하여 1995년에는 적조로 인해 약 764억의 손실이 발생한 사례가 있다.(연합뉴스, 2019.09) 이후에도 적조현상은 점점 광역화, 장기화, 고밀도화 되면서 연평균 110억 이상의 피해를 지속적으로 주고 있다. 본 연구에서는 대상 지역을 대한민국 완도로 설정 하였다. 섬이라는 지역의 특성 상 가뭄이 발생하면 식수원의 공급이 어렵고 평시에도 물을 아끼기 위한 노력이 끊이지 않는 곳이다. 실제로 완도는 우리나라에서 가장 많은 피해이력이 있는 지역이다. 또 2016년 완도에서는 적조로 인해 전복이 집단 폐사하며 358억의 피해를 입은 사례가 있다.(중앙일보, 2016.09) 그렇기에 완도지역을 대상 지역으로 하여 비강우의 장기화 등의 이유로 나타나는 가뭄을 기상학적 가뭄지수 SPI를 활용하여 분석하고 ROC 분석을 통해 수온의 상승 시 나타나는 적조현상과의 관계를 분석함으로서 적조현상이 발생하는 한 척도로 가뭄의 발생 및 장기화를 생각 할 수 있는지 판단하고자 한다.

• Spatial Information Research
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• v.13 no.3 s.34
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• pp.253-260
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• 2005

The aim of this study is to analyze the temporal and spatial distribution aspects of red tide using GIS techniques. The damage caused by red tide appears various aspects according to the species, concentration and spatial distribution of red tide plankton. Therefore, in order to prevent the damage of red tide it is important to understand the distribution characteristics of red tide by each species according to time and space. In this perspective, we analyzed the beginning outbreak area, spatial occurrence frequency and spatial migration of red tide. The spatial data used by this study was constructed by digitizing the red tide quick report and coupled with various attributes such as species, concentration and water temperature for construction of red tide database. We used various spatial analysis methods such as union, intersect, tracking, buffer and spatial interpolation for analyzing temporal and spatial characteristics of red tide. From the result of these spatial analyses, we could get the spatial information on the temporal and spatial distribution characteristics of red tide at the Southern Sea.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.402-403
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• 2000

적조의 원인생물에는 분류학적으로 다양한 종류가 속하며, 이 중 와편모조류는 대표적이라 할 수 있다 (박 등, 1988). 일부 와편모조류는 생활사 중 휴면포자로 해양퇴적토의 표층에서 일정기간 생존하다가 외부환경이 좋아지면 유영세포로 발아하여 다시 번무를 일으킴으로써 적조의 발생 분포 지역의 확대와 발생빈도를 더욱 증가시킨다 (Steidinger and Haddad, 1981; Hallegraeff, 1993; Ishikawa and Taniguchi, 1994; Nehring, 1995). (중략)

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.4
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• pp.926-932
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• 2004

This study deals with the statistical analyses on the relationship between the red tide formation and the meteorological factors in the Korean coastal waters. From 1995 to 2002, the red tide was observed every year and the number of occurrences increased as well. The red tide mostly occurred in July, August, September and October. from multiple linear regression, the meteorological factors governing the mechanisms of the increase in the number of red tide occurrences are found to be a water temperature, rainfall, sunshine duration and wind velocity. But water temperature as the limited factor controlling the growth of phytoplankton (Cochlodinium polykrikoids) in 15∼$30^{\circ}c$. NO ＝ 8.089 - 0.319WT + 0.019RF + 0.141SD + 0.l19WV (R ＝ 0.897) in August NO = 7.531 - 0.327WT + 0.027RF + 0.208SD + 0.208WV (R ＝ 0.894) in September Here, NO is the number of occurrence for red tide, WT is water temperature, RF is rainfall, SD is sunshine duration and WV is wind velocity, respectively. The necessary times till the day of red tide occurrence verse the day when water temperature reaches $15^{\circ}c$ are 78∼104 days, then it should be divided the coastal waters into 4 areas by the comparison among the accumulated sunshine duration, water temperature and rainfall as follows； the South West Coast (SW), South Middle Coast (SM), South East Coast(SE) and East South Coast (ES). The coastal areas that red tide occurs were complicated and various by change of marine environments. Usually red tide with a high concentrations (individual number, cells/ml) appeared in SM and SE. It was found that the general situations for the frequencies of red tide formation are mainly concentrated to 24.5∼$25^{\circ}c$ (high water temperature) and eve. 1000 cells/ml (high individual number) such as the category of red tide warning.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.3
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• pp.113-121
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• 2015

Building using masonry accounts for most of the smaller houses in Korea but due to brittle behavior and low ductility the frequency of usage has decreased in recent years. Despite this, this form of building has been gaining attention overseas for its low cost in construction and environment-friendliness of the materials. As such, many studies are being conducted to resolve the disadvantages in structure. This study produced an specimen for masonry-filled wall and the intersection to confirm the difference in structural movement depends on the existence or lack of expansion joint and verified the reinforcement effect from inserting a connecting steel item (steel plate, stainless steel twist bar). The experiment results show that the specimen with a steel plate inserted saw an increase in durability and an improvement in the strength of the specimens, while the specimen that had stainless steel twists bar inserted saw an increase in ductility that did not cause brittle failure, indicating that the reinforcement effects of inserting a connecting steel item are effective.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.11a
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• pp.221-224
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• 2006

각각의 유입오염원에 의한 오염가중은 연일지구 무처리 방류수에 의해 $BOD_5$, $COD_{Mn}$, T-N T-P가 각각 17.40%, 12.36%, 7.52%, 29.90%증가 한다. 효자지곡 지구 오염물질유입으로 인한 오염가중은 $BOD_5$, $COD_{Mn}$, T-N T-P가 각각 7.99%, 6.82%, 12.60%, 29.55%증가한다. 하수처리장 방류수의 오염물질유입으로 인한 오염가중은 $BOD_5$, $COD_{Mn}$, T-N T-P가 30.65%, 14.61% 44.75%, 67.43% 증가할 것으로 예측된다. 겨울철 형산강 본류의 유량감소로 인해 오염물질의 농축량이 증가한다. 이에 겨울철 및 강우량이 적은 시기에 적조 발생빈도가 높아지는 것으로 판단된다.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.165-169
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• 1998

Anthers of three cross combinations of hot-pepper(Capsicum annuum L.) were cultured on Dumas De Vaulx medium supplemented with some growth regulators. The embryo production efficiency and the diversity for agronomic traits in $A_2$ lines were investigated. The embryo production frequencies of hybrid combinations were ranged from 16.4% to 43.4%, the highest embryo induction combination was DGSH $\times$ C-NH with 43.4% embryogenic efficiency. Among total 275 $A_2$ lines, phenotypic variants were found in six lines, 2.1% variant frequency. The diversity of $A_2$ lines derived from anther culture was different according to the cross combinations. Fruit color was within parental range, no transgressive variation was observed. However leaf color showed transgressive variation. In fruit length, fruit width and fruit weight, one C-HC $\times$ DGSH and DGSH $\times$ C-NH showed great diversity compared with doner parents while Cheokjo 1 $\times$ C-NH crossed with Cheokjo 1 with big fruit shape showed small diversity. Stem length to 1st branch was relatively similer to or longer than donor parents. Stem thick exhibited remarkable diversity. Node number to 1st branch distributed alomost within the range of donor parents in C-HC $\times$ DGSH combination, however great transgressive variations were observed in DGSH $\times$ C-NH and Cheokjo 1 $\times$ C-NH combinations.