• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.291-291
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• 2020

제주도는 강수의 지표침투성이 좋은 화산섬의 지질특성상 지표수의 개발이용여건이 취약한 관계로 용수의 대부분을 지하수에 의존하고 있다. 따라서 제주도는 정책 및 연구적으로 오랜 기간동안 지하수의 보전관리에 많은 노력을 기울여 오고 있다. 하지만 최근 기후변화로 인한 강수의 변동성 증가로 인해 지하수위의 변동성 또한 증가할 가능성이 있으며 따라서 지하수위의 급격한 하강에 대비하여 지하수위의 예측 및 지하수 취수량 관리의 필요성이 요구되고 있다. 지하수에 절대적으로 의존하고 있는 제주도의 수자원 이용 여건을 고려할 때, 지하수의 취수량 관리를 위한 지하수위의 실시간 예측이 필요한 실정이다. 하지만 기존의 예측방법에 의한 제주도 지하수위 예측기간은 충분히 길지 않으며 예측기간이 길어지면 예측성능이 낮아지는 문제점이 있었다. 본 연구에서는 이러한 단점을 보완하기 위해 딥러닝 알고리즘인 Long Short Term Memory(LSTM)를 활용하여 제주도 남동쪽 표선유역 중산간지역의 1개 지하수위 관측정에 대해 지하수위를 예측하고 분석하였다. R 기반의 Keras 패키지에 있는 LSTM 알고리즘을 사용하였고, 입력자료는 인근의 성판악 및 교래 강우관측소의 일단위 강수량자료와 인근 취수정의 지하수 취수량자료 및 연구대상 관측정의 지하수위 자료를 사용하였으며, 사용된 자료의 기간은 2001년 2월 11일부터 2019년 10월 31일까지 이다. 2001년부터 13년의 보정 및 3년의 검증용 시계열자료를 사용하여 매개변수의 보정 및 과적합을 방지하였고, 3년의 예측용 시계열자료를 사용하여 LSTM 알고리즘의 예측성능을 평가하였다. 목표 예측일수는 1일, 10일, 20일, 30일로 설정하였으며 보정, 검증 및 예측기간에 대한 모의결과의 평가지수로는 Nash-Sutcliffe Efficiency(NSE)를 활용하였다. 모의결과, 보정, 검증 및 예측기간에 대한 1일 예측의 NSE는 각각 0.997, 0.997, 0.993 이었고, 10일 예측의 NSE는 각각 0.993, 0.912, 0.930 이었다. 20일 예측의 경우 NSE는 각각 0.809, 0.781, 0.809 이었으며 30일 예측의 경우 각각 0.677, 0.622, 0.633 이었다. 이것은 LSTM 알고리즘에 의한 10일 예측까지는 관측 지하수위 시계열자료를 매우 적절히 모의할 수 있다는 것을 의미하며, 20일 예측 또한 적절히 모의할 수 있다는 것을 의미한다. 따라서 LSTM 알고리즘을 활용하면 본 연구대상지점에 대한 2주일 또는 3주일의 안정적인 지하수위 예보가 가능하다고 판단된다. 또한 LSTM 알고리즘을 통한 실시간 지하수위 예측은 지하수 취수량 관리에 활용할 수 있을 것이다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.4
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• pp.815-820
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• 2015

For the establishment of effective water resources management platform for Jeju-Island, the characteristics, including surface runoff, evapotranspiration, groundwater recharge and discharge are to be properly quantified. Among these hydrologic components, interception due to vegetation is very important factor but it is hard to be quantified. After Von Hoyningen-Huene (1981) found the relationship between LAI (Leaf Area Index) and interception storage, LAI has been used for key factor to estimate interception and transpiration. In this study the equation suggested by Kozak et al. (2007) is implemented in SWAT-K (Soil and Water Assessment Tool - Korea) model and is tested at the Cheonmicheon watershed in Jeju-Island. The evaporation due to interception was estimated as 85~104mm, 8~11% of whole evaporation. Therefore it is necessary to consider the evaporation due to interception as a controlling factor to water budget of this watershed.

• Parasites, Hosts and Diseases
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• v.27 no.3
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• pp.171-176
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• 1989

Total 2,829 persons consisted of 1,019 general patients and 1,030 asthma- suspected patients who visited Kangnam 51. Mary's Hospital and 780 general patients who visited Cheju Medical Center were examined for the antibody titers of Toxo- plasma by indirect latex agglutination(ILA) test. Nineteen out of 1,019(1.86%) cases in general patients group, 11 out of 1,030 (1.07%) cases in asthma patients group, and 45 out of 780(5.77%) cases in Cheju patients group showed positive ILA titers. Concerned with the age and ILA positive cases, general and asthma patients ex- pressed more cases at thirties to sixties while Cheju patients showed high incidence at children and adolescents in addition to the above mentioned ages. Frequencies of ILA positive titers were highest in 1 : 32 and 1 : 64, and some cases showed 1 : 2,048 or higher titers.

• The Journal of the Korea Contents Association
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• v.20 no.5
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• pp.585-594
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• 2020

After the launch of Jeju Special Self-Governing Province in 2006, a number of real estate development projects were carried out; the real estate industry has relatively largely grown as compared with other regions since 2011. This growth has slowed down in 2017, along with the increase of unsold houses and the short of its incoming population, causing its real estate market recession. This study analyzed the source of real estate industry growth in Jeju: either affected by national growth power or its regional competitiveness. This study applied Shift-Share Analysis and Growth Differential Analysis, by dividing the recovery period ('06~'10) and expansion period ('11~'16). According to the result, sales amount and the number of employees in the real estate industry in Jeju had grown in the recovery period based on the national growth power. Its regional competitiveness and stable industrial structure grew in the growth period. Development and subdividing of real estate contributed to the growth of the real estate industry in Jeju. On the other hand, management of real estate weakened its market.

• The Journal of the Korean dental association
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• v.57 no.7
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• pp.372-378
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• 2019

The dental implants in modern dentistry brought out a new era in everyday dental practice. Increasing of dental implants usage, various failures and complications has occurred. Failures and complications of dental implant treatments that can happen in implant surgery, in mechanical or prosthetic problem and in biological aspect. The aim of this study was to assess implant failures for 6 years as well as find out how to overcome implant failure. In Jeju National University hospital, 26 dental implants in 17 patients were removed by implant failure through 2013.1.1.-2018.12.31. Each implant failure case was analyzed in report form with various informations about failure retrospectively. The present study showed 26 failed dental implants of 17 patients were removed. 13 implants(50%) of 8 patients(47.06%) were failed before functional loading and 13 implants(50%) of 9 patients(52.94%) were failed after functional loading. 11 implants(42.31%) of 7 patients(41.18%) with medical disease were extracted. 6 implants(23.08%) of 5 patients(29.41%) with additive bone graft were failed. We discuss with 26 failed dental implants of 17 patients about their causes, solutions and prevention retrospectively for 6 past years. Precise diagnosis and treatment planning are needed. Medically compromised patients and patients with implants and additive bone grafts should be cautiously treated with high failing possibilities.

• 한국정보교육학회:학술대회논문집
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• 2021.08a
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• pp.7-11
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• 2021

This study designs block-based machine learning education program using sound data that can be easily applied in elementary schools. The education program designed its goals and directions based on the results of a demand analysis conducted on 70 elementary school teachers in advance according to the ADDIE model. Scratch in Machine Learning for Kids was used for block-based programming, and the education program was designed to discover regularity of data values using sound data, learn the principles of artificial intelligence, and improve computational thinking in the programming process. In a later study, the education program needs to verify what changes there are in attitudes and computational thinking about artificial intelligence.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.55-58
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• 2003

제주도 동부지역에 위치한 심부관측정(해수면 하 60m 이상 착정) 11개소를 대상으로 2001 년 11월부터 2002년 10월까지 1년간 담.염수 경계면의 분포와 변화에 대하여 조사를 실시하였다. 담.염수 경계면의 두께는 대체로 해안에서 내륙 쪽으로 향함에 따라 두터워지는 경향을 나타냈고, 해안에서 6~6.kmm 이상 지역에는 담.염수 경계면을 갖는 기저지하수체가 발달하지 않는 것으로 조사되었다. 또한, 담.염수 경계면은 조석의 영향에 의해 1일 동안 최대 8.1m, 최소 0.14m의 변화를 나타냈으며, 계절에 따라서는 최대 33.2m, 최소 2m의 수축 및 확장을 일으키는 것으로 조사되었다. 조석과 계절에 따른 담.염수 경계면의 수축과 확장의 폭은 조사대상 관측정의 위치, 지하지질, 강우량 등의 여러 가지 요인에 의해 좌우되고 있는 것으로 해석되었다.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.177-183
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• 2018

This study examined the seasonal, regional distribution of mosquito vectors related with disease vectors in the Jeju. From March to November, sample were collected from 11 points in four environmentally different sites in Jeju Island. Samples were collected twice a month using a black-light trap and a BG sentinel trap. Overall, five genera and seven species types of 6,042 female mosquitos were collected. Among the collected mosquitos, 4,159 (68.8%) and 1,348 (24.4%) were Culex pipiens and Aedes albopictus, respectively, making them the dominant species. Additionally, collection using the black light trap produced 72.8 entities per trap in Jungang-dong service center in the center of the city, which was the highest value, while the lowest amount of 1.4 per trap was recovered from the airport. When the BG sentinel trap was used, the largest recovery was observed in the port, where there were 71.7 entities per trap, while the lowest amount of 28.3 entities per trap was recovered at Gealmae Eco Park. The overall number of mosquitoes collected started to increase from May, and reached the largest value of 1,156 (19.1%) in August. Trapped mosquitoes are created 364 pools of up to 50 grains per pool, by season, by environmental, and by species. When the pools were used, no flaviviral infection was observed upon real time RT-PCR.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.211-212
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• 2002

• JOURNAL OF ELECTRICAL WORLD
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• s.348
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• pp.2-4
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• 2005

대한전기협회는 11월 25일부터 26일까지 양일간 제주도 라마다 호텔에서 중소기업의 전력신기술 개발의욕을 높이고 개발된 신기술의 활용도를 증진시키기 위한‘전력신기술 워크샵’을 개최했다.