• 한국해양환경ㆍ에너지학회지
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• 제14권4호
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• pp.257-263
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• 2011

SBM을 이용하여 2006년 가막만의 담수, 염분, 영양염 등 물질 수지를 산정하였다. 담수유출량은 $-174.2{\sim}72.5{\times}10^3m^3/day$로 나타났으며 개방경계에서의 해수 교환에 의한 mixing volume은 $-2.4{\times}10^7\sim4.9{\times}10^7m^3/day$로 만 내외의 염분차이에 의해 크게 좌우 받았다. 육상기인 DIP와 DIN의 유입 flux의 범위는 397.0~1158 mole/day 및 1750~8328 mole/day의 범위로 다른 지역에 비해 낮았다. DIP의 소실 또는 생성은 물수지의 변동에 의해 크게 좌우 되는 특징을 보였으며, 또한, 물질체류시간에 의해 물질수지가 크게 좌우되어 NEM도 크게 달라지는 결과를 보였다.

• 한국멀티미디어학회논문지
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• 제22권11호
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• pp.1269-1279
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• 2019

In medical image analysis, segmentation is considered as a vital process since it partitions an image into coherent parts and extracts interesting objects from the image. In this paper, we consider automatic segmentations of OCT retinal images to find six layer boundaries using convolutional neural networks. Segmenting retinal images by layer boundaries is very important in diagnosing and predicting progress of eye diseases including diabetic retinopathy, glaucoma, and AMD (age-related macular degeneration). We applied well-known CNN architecture for general image segmentation, called Segnet, U-net, and CNN-S into this problem. We also proposed a shortest path-based algorithm for finding the layer boundaries from the outputs of Segnet and U-net. We analysed their performance on public OCT image data set. The experimental results show that the Segnet combined with the proposed shortest path-based boundary finding algorithm outperforms other two networks.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2007년 가을학술발표회
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• pp.558-569
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• 2007

It is important to obtain real-time data from long-term monitoring of landfills and develop leachate leakage detection system for the integrated management of landfills. A novel real time monitoring system and early leakage detection system was suggested in this study. The suggested monitoring system is composed of two parts; (1) a set of moisture sensors which monitor the areas surrounding the landfill, and (2) a set of moisture and temperature sensors which monitor the landfill inside. For the assessment for landfills stabilization, real-time monitoring system was evaluated in dry and wet cell of pilot-site. In addition, the grid-net electrical conductivity measurement system was also suggested as early leakage detection system. In this study, the field applicability of suggested systems was evaluated through pilot-scale field tests. The results of pilot-scale field model tests indicate that the grid-net electrical conductivity measurement method can be applicable to the detection of landfill leachate at the initial stage of intrusion, and thus has a potential for monitoring leachate leakage at waste landfills.

• International Journal of Precision Engineering and Manufacturing
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• 제1권2호
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• pp.55-60
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• 2000

A comparison of Riveted and bonded repairs, bearing and net tension failures, and Al 6061-T6 plates is presented. The results are then compared with previous papers about bonded repairs on different patch materials and shapes. Aluminum alloys, including Al 6061-T6, have a face-centered-cubic crystal structure. Under normal circumstances, these types of crystal structures do not exhibit cleavage fractures even at very low temperatures. In aluminum-base structures, the cracked plate structures are frequently repaired using mechanical fasteners-either rivets of bolts- even though patch-bonding techniques are applied to repair and reinforce the structure. Static test results indicate that the riveted repairs are affected by the position of the rivers. When using the same size of patch, the bonded repair technique is stronger; the rate of elongation is also increased. Form FEM analysis, it is revealed the origin of patch debonding in patch-bonded structures is the edge of the patch along to the tensile strength.

• 원예과학기술지
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• 제32권5호
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• pp.584-589
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• 2014

Jeffersonia dubia is a spring-flowering perennial found in rich forests in Korea and Northern China and has potential as an ornamental or medicinal plant. However, illegal picking and land use change have decreased the number of populations and overall population size of this plant in its natural habitat. Although J. dubia has been reported to be a shade-preferring plant, no study has determined the optimum light intensity for its growth. The objectives of this work were to observe the effects of various shading levels on the physiological responses of J. dubia and to determine the proper shading level for cultivation. Treatments consisted of four shading levels (0%, 50%, 75%, and 95% shade) imposed using black mesh cloth. The number of leaves and dry weight increased with decreased shading. The shoot-to-root ratio increased with increased shading, mainly due to decreased root dry weight under shading. Plants showed low net $CO_2$ assimilation rates and $F_v/F_m$ values combined with low dry matter levels when grown under 0% shade (full sunlight). These results indicate that J. dubia plants experience excessive irradiance without shading, resulting in damage to the photosynthetic apparatus. By contrast, the net photosynthesis rate increased as the shading level increased. $F_v/F_m$, the potential efficiency of PSII, was 0.8 under 95% shade, indicating that J. dubia is well-adapted under heavy shading. However, the low dry matter of plants in the 95% shade treatment indicated that the low light intensity under 95% shade led to a decline in plant growth. Thus, moderate light (50% shading) is recommended for cultivating J. dubia without physiological defects.

• 한국산림과학회지
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• 제98권3호
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• pp.263-271
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• 2009

본 논문의 목적은 2013년 이후(Post-2012) 개도국의 산림전용으로 인한 온실가스 배출량 감축(RED) 및 산림 탄소축적증진(EFCS) 활동과 관련된 협상 대안을 구체화하고 거래 가능한 탄소배출권을 인센티브로 가정하여 대안별 감축잠재량 평가 및 이를 토대로 환경편익과 국익을 고려한 우리나라 협상 전략을 제시하는 데 있다. 이를 위해 'FAO 세계산림자원평가' 보고서를 이용하여 99개 대상 국가를 선정하고 이들 국가를 대상으로 RED 및 EFCS 활동에 따른 온실가스 감축잠재량과 탄소배출권 잠재력을 추정하였다. RED의 감축잠재량은 'baseline and credit' 탄소계정 방법을, EFCS 활동에 대한 감축잠재량은 gross-net 및 net-net 탄소계정 방법을 적용하였다. 분석 결과, 산림전용율이 높은 브라질, 인도네시아, 콩고 등이 RED를 통해, 산림탄소축적 증가율이 높은 중국, 칠레, 한국 등이 EFCS 활동을 통해 탄소배출권을 받을 수 있는 잠재력이 컸다. 지구적 차원에서 보면, RED 및 EFCS 활동을 동시에 수행할 경우 감축잠재량이 가장 크다는 환경 편익 측면과 한 활동만 인센티브를 줄 경우 대상에서 제외되는 국가가 발생한다는 형평성을 고려하여 우리나라 협상 전략으로 두 가지 활동 모두를 정치적 접근 및 인센티브 부여 활동에 포함할 것을 제안한다. 단, EFCS 활동의 경우 비인위적 활동 효과를 제거하기 위해 산림경영 활동의 탄소계정 방법론에서 채택한 할인율 적용을 대안으로 제시한다.

• 한국산림과학회지
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• 제95권4호
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• pp.398-404
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• 2006

본 연구는 해발고와 사면에 따른 신갈나무림의 바이오매스와 연간 순생산량을 구명하기 위해 강원 평창 중왕산 지역을 조사하여 다음과 같은 결론을 얻었다. 중왕산 지역 60-70년생 신갈나무림의 바이오매스 현존량은 해발 1,300m에서 북사면 211.6 ton/ha, 남사면 200.3 ton/ha, 해발 1,000m에서 북사면 252.9 ton/ha, 남사면 212.3 ton/ha, 해발 800m에서 북사면 256.7 ton/ha, 남사면 232.4 ton/ha로서 해발고가 낮아질수록 바이오매스가 증가하였으며, 북사면이 남사면보다 바이오매스가 더 많았다. 또한 연간 순생산량은 해발 1,300m에서 북사면 12.7 ton/ha/yr, 남사면 14.0ton/ha/yr, 해발 1,000m에서 북사면 17.3 ton/ha/yr, 남사면 14.2 ton/ha/yr, 해발 800m에서 북사면 14.5 ton/ha/yr, 남사면 14.6 ton/ha/yr로서 남사면에서는 해발고가 낮아짐에 따라 증가하는 반면 북사면에서는 해발 800m 부위보다 해발 1,000m 부위에서 더 높은 것으로 나타났다. 해발고에 따른 신갈나무림의 연간 순생산량을 비교하면 5% 유의수준에서 차이가 있는 것으로 나타났으나, 사면에 따른 차이는 나타나지 않았다.

• 생물환경조절학회지
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• 제29권2호
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• pp.120-129
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• 2020

본 연구는 '후지/M.9'와 '홍로/M.9'가 재식된 사과원에 바람이나 우박을 막기 위해 사용되는 망(구멍크기 : 2×2mm)을 수관상부에 색상별로 백색과 청색을 나누어 설치한 후 햇빛의 차광정도 및 생육환경 차이 등에 따른 과실품질 변화를 조사하였다. '후지' 사과의 경우 대기온도 34.8℃인 오후 2~3시경의 과실표면 온도를 측정한 결과, 무처리는 40.0℃로 가장 높았고, 청색 방풍망과 백색 방풍망 처리구는 각각 34.9℃, 36.6℃로 크게 낮았다. '홍로'에서는 무처리구가 44.2℃일 때, 청색 방풍망 처리구는 38.3℃, 백색 방풍망 처리구는 38.5℃를 기록하여 '후지'와 마찬가지로 온도 경감효과를 보였다. '후지'의 과피색차를 조사한 결과, 과피적색도(a^⁎)는 무처리구가 16.5, 청색 방풍망 처리구는 18.0였으나, 백색 방풍망 처리구는 19.3으로 가장 높은 값을 보였다. '홍로'에서도 백색 방풍망 처리구가 적색도가 34.9로 무처리구 28.1에 비해 유의하게 높은 적색도 발현을 보였다. 일소피해 조사결과, '후지'에서 청색 방풍망 처리구 3.8%, 백색 방풍망 처리구 4.2%로 무처리구 9.4%에 비하여 크게 경감되었고, '홍로'의 경우는 청색 방풍망 처리구는 8.8%, 백색 방풍망 처리구는 12.4%로 무처리구 28.8%에 비하여 일소발생이 현저히 감소하였다. 이 같은 결과는 처리별 자외선 수치를 측정하였을 때 무처리 구간의 자외선 값에 비해 청색 방풍망 처리구에서 유의하게 낮아 방풍망 처리에 의한 자외선 차단 효과에 의한 것을 확인할 수 있었다.

• 한국수산과학회지
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• 제48권5호
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• pp.776-782
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• 2015

We examined the community structure of fish off the coast of Jindo Island in response to a cold water appearance in the southwestern sea of Korea each August between 2013–2015. Using a gape net with wings, we collected 31 taxa during the study period, wherein the most dominant species was Engraulis japonicus. Collichthys lucidus and Neosalanx andersoni, which are mainly distributed in the western sea of Korea, increased in abundance and were dominant in August 2013, possibly due to the apparent intrusion of cold water (< 19°C) from offshore into the coastal waters of Jindo Island. Meanwhile, Scomberomorus niphonius and Sardinella zunasi, which are known as warmwater migratory species, increased in abundance and were dominant in August 2015, likely influenced by the warmer water (> 20°C) at the coast, which resulted in a noticeable lessening of the cold water in the study area. However, no significant differences were observed in fish community structure in the month of August between 2013–1015. This implies that the small-scale spatial and temporal variations in the cold water had limited effects on the fish community structure, even though the abundances of several dominant species varied in the coastal waters.

• 수산해양기술연구
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• 제56권2호
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• pp.155-162
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• 2020

The adjudication of Korean Maritime Safety Tribunal (KMST) was analyzed to collect basic data to identify the cause of the risk that did not appear in the current data provided by the fishermen's occupational accidents of the National Federation of Fisheries Cooperative (NFFC) in stow net fishing vessel from 2015 to 2019. The personnel's carelessness was the most common in 29 out of 33 accidents (87.9%), followed by 25 cases (75.8%) of inadequacy of instructions, 24 cases (72.7%) of inadequacy of education on hazard factor, 20 cases (60.6%) of no personal protection equipment, 18 cases (54.5%) of poor guard, 17 cases (51.5%) of inadequacy of work method, 16 cases (48.5%) of absence of emergency stop button, 14 cases (42.4%) of work practice of poor safety precautions that affected more than 40% of all accidents as accident causes. These causes had a strong influence on each other, and the ratio of accident causes is high. With this relationship, accidents can be prevented or the severity of human injury can be reduced if types of accident process can be estimated with a scenario, and the key points before the accident in the scenario are switched to safe points.