• 해양환경안전학회지
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• 제29권1호
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• pp.24-35
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• 2023

급격한 산업화와 도시화로 인해 해양 오염이 심각해지고 있으며, 이러한 해양 오염을 실효적으로 관리하기 위해 수질평가지수(Water Quality Index, WQI)를 마련하여 활용하고 있다. 하지만 수질평가지수는 다소 복잡한 계산과정으로 인한 정보의 손실, 기준값 변동, 실무자의 계산오류, 통계적 오류 등의 불확실성(uncertainty)을 내포하고 있다. 이에 따라 국내·외에서 인공지능 기법을 활용하여 수질평가지수를 예측하기 위한 연구가 활발히 이루어지고 있다. 본 연구에서는 해양환경측정망 자료(2000 ~ 2020년)를 활용하여 우리나라 전 해역 즉, 5개의 생태구에 대한 WQI를 추정할 수 있는 가장 적합한 인공지능기법을 도출하기 위해 총 6가지의 기법(RF, XGBoost, KNN, Ext, SVM, LR)을 실험하였다. 그 결과, Random Forest 기법이 다른 기법에 비해 가장 우수한 성능을 보였다. Random Forest 기법의 WQI 점수 예측값과 실제값의 잔차 분석 결과, 모든 생태구에서 시간적 및 공간적 예측 성능이 우수한 것으로 나타났다. 이를 통해 본 연구에서 개발한 Random Forest 기법은 높은 정확도를 바탕으로 우리나라 전해역에 대한 WQI를 예측 가능할 것으로 사료된다.

• 대한원격탐사학회지
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• 제38권4호
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• pp.435-446
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• 2022

Identifying ship types is an important process to prevent illegal activities on territorial waters and assess marine traffic of Vessel Traffic Services Officer (VTSO). However, the Terrestrial Automatic Identification System (T-AIS) collected at the ground station has over 50% of vessels that do not contain the ship type information. Therefore, this study proposes a method of identifying ship types through the Random Forest Classifier (RFC) from dynamic and static data of AIS and V-Pass for one year and the Ulsan waters. With the hypothesis that six features, the speed, course, length, breadth, time, and location, enable to estimate of the ship type, four classification models were generated depending on length or breadth information since 81.9% of ships fully contain the two information. The accuracy were average 96.4% and 77.4% in the presence and absence of size information. The result shows that the proposed method is adaptable to identifying ship types.

• Journal of Forest and Environmental Science
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• 제24권2호
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• pp.69-77
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• 2008

Jatropha curcas L. is an oil bearing species with many uses and considerable economic potential as a biofuel crop. Salt stress effect on growth, ion accumulation, contents of protein, proline and antioxidant enzymes activity was determined in callus and seedling to understand the salt tolerance of the species. Exposure of callus and seedling to salt stress reduced growth in a concentration dependent manner. Under salt stress Na content increased significantly in both callus and seedling whereas, differential accumulation in the contents of K, Ca, and Mg was observed in callus and seedling. Soluble protein content differed significantly in callus as compared to seedling, however proline accumulation remained more or less constant with treatments. The proline concentration was ~2 to 3 times more in callus than in seedling. Salt stress induced qualitative and quantitative differences in superoxide dismutase (SOD; E.C. 1.15.1.1) and peroxidase (POX; E.C. 1.11.1.7) in callus and seedling. Salt induced changes of the recorded parameters were discussed in relation to salinity tolerance.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.598-601
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• 2006

The Purpose of this study is to develope the method for early recovery of the biodiversity in the oligotrophical costal area, it is important in the recovery of the biodiversity to make kelp forest grow in the concerned area. In order for it, sufficient nutrient is required as well as the proper seedbed, Hence in this study, granulated fertilizer, which contains nutrient, such as nitrogen, phosphorus and etc, is coated by cement paste, and then is mixed in to the porous concrete in order to provide seedbed and nutrient simultaneously. As a result of examination of growth property of marine plants of multiple performance concrete for kelp forest regeneration, seaweeds is adhered plentifully when the number of days is longer. when the granular fertilizer mixed. adherence and growth of marine plants is excellent and is stabilized over the long run. In case 6 month of the number of days immersed, marine plants and growth will appear.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2017년도 정기학술대회 발표논문집
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• pp.197-197
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• 2017

• 한국수산과학회지
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• 제40권4호
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• pp.220-225
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• 2007

The succession of marine benthic algae and the restoration of an artificial seaweed forest on a porous type (shaped half saw teeth) artificial reef at Jeju island, Korea was studied. Young thalli of Sargassum horneri and Ecklonia cava were attached to different artificial substrates. In general, the succession on the artificial reefs led from filamentous algae to perennial algae and involved more than 25 species that are useful fishery resources, including E. cava. Coralline algae were dominant on the artificial reefs at the Kangjung site. The maximum algal biomass on the artificial reef in October 2005 was $1,990g/m^2$ at Biyang. In conclusion, a climax community and seaweed forest can be attained one year after the substrate is constructed.

• The Korean Journal of Ecology
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• 제14권1호
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• pp.49-61
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• 1991

Phytosociological invesstigation of the forest vegetation was carried out in Oinrodo island at the period from June 5th 1990 to June 10th 1990 by Braun-Blanquet's method. The forest vegetation was classified into 10 communities, Castanopsis cuspidata var. sieboldii, Machilus thunsbergii, Neolitsea sericea, Quercus glauca-Actinodaphne lancifolia, Pinus thunbergii, Chamaecyparis obtusa, Cryptomeria japonica, Quercus acutissima, Quercus variabilis, and Carpinus coreana community. Based on the classification of communities, the actual vegetation map was drawn in 1 : 50,000 scale.

• 한국환경농학회지
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• 제41권3호
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• pp.217-221
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• 2022

BACKGROUND: Gotjawal forest on Jeju Island is characterized by uneven topography that developed as a result of freezing-thawing weathering process and irregular substrates caused by numerous lava-flow collapses. Sanyang Gotjawal, located in southwest of Jeju Island, is a well-developed forest with a long history. In addition to photographs, there is a need for a good way to describe the unique features of Gotjawal, including its geology and vegetation. METHODS AND RESULTS: We illustrated the area's natural features using Clip Studio Paint 1.12.0. To reveal its complexity, we separated the vegetation and geological features in the illustrations. CONCLUSION(S): We drew a cross-section of Gotjawal's unique layers, including lava flows. In addition to an eco-geological approach, we described the dominant vegetation and geological characteristics of the three forest layers (trees, shrubs, and herbs) in Gotjawal.

• The Korean Journal of Ecology
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• 제13권4호
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• pp.343-359
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• 1990

Phytosociological investigation of the forest vegeation was carried out in Kumo archipelago at the period of May 21th 1990 to May 29th 1990 by Braun-Blanquet's method. The forest vegetation was classified into 7 communities, Camellia japonica, Castanopsis cuspidata var. sieboldii, Machilus thunbergii, Camellia japonica-Pinus thunbergii, Camellia japonica-Torreya nucifera, Carpinus coreana and Quercus acutissima community. Based on the classification of communities, the actual vegetation maps were drawn in 1 : 50,000 scale.

• 한국환경생태학회지
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• 제31권6호
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• pp.529-536
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• 2017

이 연구는 제주연안 해역에서 갯녹음의 확산동향과 기후변화로 인한 동계 수온변화(수온상승)가 갯녹음 확산에 미치는 영향을 알아보고 갯녹음 원인생물인 무절석회조류의 번식과 생장을 파악하기 위해 연구되었다. 제주연안의 갯녹음 발생면적은 1998년에는 2,931ha였으나, 2003년에는 4,541ha로 증가하였다. 발생해역도 1998년은 제주도 남부해역에서 주로 발생했으나, 2003년에는 조천읍, 구좌읍을 제외한 제주도 전역으로 확산되었다. 1992년부터 2004년까지 관측된 2월 평균수온은 갯녹음 해역 $15.1^{\circ}C$, 해중림 해역 $13.9^{\circ}C$로 갯녹음 해역이 $1.2^{\circ}C$가 높게 나타나 두 해역 간 뚜렷한 차이를 보였으나, 8월 수온은 두 해역 간 차이가 없었다. 수온의 장기변동(37년)에서도 갯녹음 해역이 평균 $15.3^{\circ}C$인데 비하여 해중림 해역은 평균 $14.1^{\circ}C$로 갯녹음 해역이 해중림 해역보다 $1.2^{\circ}C$가 높게 나타났다. 연간 수온 증가 값은 갯녹음 해역이 매년 $0.038^{\circ}C$씩 증가하고 있는 반면, 해중림 해역은 $0.024^{\circ}C$씩 증가하여 장기 수온변동은 갯녹음 해역이 해중림 해역보다 높았다. 이와 같이 기후변화로 인한 지속적인 동계 수온상승은 제주도 갯녹음을 확대시키고 있음을 시사하고 있다.