• 한국수산과학회지
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• 제37권3호
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• pp.249-254
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• 2004

The hydro-acoustic method is widely used for estimating biomass and distribution of fisheries resources along the coast and in the ocean. High costs and time are necessary to construct systems for this method and to initially educate specialists. It has been used in fisheries of advanced nations like Japan and Norway, because it is more efficient than other methods. In order to research the behavior of fish around an artificial reef using an echo sounder, volume backscattering strength (SV) and fish per cubic meter (FPCM) of darkbanded rockfish around the model artificial reef in a water tank were measured. Moreover, behavior of fish was observed in an adjacent artificial reef, which was constructed at Tongyeong marine ranching area. Following that, an acoustics survey was conducted at Mirukdo around the Tongyeong marine ranching area, in order to understand the spatial distribution and strength of fisheries resources. Very high patches of fish were found in a wide area around the artificial reef. It is thought that an approaching fish school around the artificial reef can be measured accurately by using an echo sounder of high resolution. Moreover, use of other monitoring methods like of diving or ROV simultaneous with an echo sounder is required in order to grasp the species and ecology of fish inhabiting the area around the artificial reef.

• Applied Microscopy
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• 제27권4호
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• pp.461-472
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• 1997

The substantia nigra of the Mongolian gerbil was studies by tyrosine hydroxylase immunohistochemistry and immunoelectron microscopy with preembedding method. The purpose was to obtain information on the distribution and ultrastructure of the Tyrosine hydroxylase immunoreactive and dopaminergic neurons in the substantia nigra, in order to provide the necessary background for the gerbil. Large number of tyrosine hydroxylase immunoreactive neurons were located in the compact part of substantia nigra. Findings in the gerbil, compared to observations in the other species, included the presence of prominent bundles of tyrosine hydroxylase immunoreactive cytoplasmic processes passing in the dorsoventral direction from pars compacta into pars reticulata at middle and caudal levels of the substantia nigra, and the presence of a distinct tyrosine hydroxylase immunoreactive substantia nigra pars lateralis. Tyrosine hydroxylase immunoreactive neurons had well-developed cell organelles, especially rough endoplasmic reticulum, free ribosome and poly-ribosome, and showed the infoldings of the nuclear envelope. We anticipate that the present description of the cellular organization of the tyrosine hydroxylase immunoreactive dopaminergic area in the substantia nigra of gerbil will be useful for the animal experimental model of Parkinson's disease.

• 한국산림과학회지
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• 제101권2호
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• pp.185-194
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• 2012

한약재 우슬로 알려진 쇠무릎과 털쇠무릎 두 변종 식물표본자료의 지리참조연산 표준화 작업을 통해, 1차종 발생데이터를 수집하면서 발생된 오류의 특성과 발생 원인을 조사하였다. 본 연구에서 시도한 재동정의 경우, 변종 수준의 동정에서는 쇠무릎의 경우 41%, 털쇠무릎의 경우 28%가 오동정으로 확인되었지만, 동정자의 동정신뢰도 수준은 변종의 동정 정확도와 무관하였다. 전체 303개 표본자료 중 71점의 지리참조연산을 실시하여 산출된 불확실성의 범위는 0.1297 km(최소)-32.4 km(최대), 평균 4,055m, 표준편차 5,772m로 확인되었다. 털쇠무릎은 한반도 중부에 넓게 분포하였으나, 쇠무릎은 경상남도와 전라남도를 포함한 남부해안 지역과 서해안 지역을 중심으로 분포하였다. 바이오클림(Bioclim) 분포모델을 적용한 결과, 쇠무릎의 최적생육지역은 남부지방 및 서부해안지역인 반면, 털쇠무릎의 경우 충청남도를 중심으로 한 중부지역임을 확인하였다. 두 분류군이 위도상으로 구분되는 가장 중요한 원인은 기후 인자 중 강수량보다는 기온인자로 확인되었다. 표본자료의 정보량을 판단하기 위해 지리참조연산결과 종의 전체적인 분포정보, 기후 정보 모델링을 통한 최적생육분포 면적 등의 정보량이 증가되었다. 본 연구에서 실시한 것과 같이 자료 품질 향상을 위해 최초 자료수집과 이후 입력까지 모든 관리 절차에서 발생하는 오류를 관리할 필요가 있다.

• 생태와환경
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• 제51권1호
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• pp.1-15
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• 2018

With land-use (cover) and water quality, the distributional characteristics of epilithic diatom communities were studied with 193 samples from estuaries of Korean peninsula between 2015 and 2016. Of total 394 taxa classified, Nitzschia perminuta (19.6%) and N. inconspicua (14.0%) were the 1st and 2nd dominant species. Using a cluster analysis, the epilithic diatom communities of Korean estuaries were divided into four groups (G1-G4). Ecological characteristics of each group were followed: G1 was located in estuaries of the East Sea, and characterized by high forest land-use and high DO and low nutrients; G2 was the eastern part of the South Sea, and characterized by low turbidity and nutrients; G3 was the western part of the South Sea, and characterized by high agriculture, low electric conductivity and low salinity; G4 was the Yellow Sea, and characterized by high nutrients. The environmental factors having significant correlation with diatom distributions were as follows: TN to G1, turbidity to G2, agriculture to G3, and TP to G4. Moreover, the important factors affecting the occurrence of indicator species were forest land-use for Fragilaria construens var. venter in G1, turbidity for Rhoicosphenia abbreviata in G2, urban land- use and total phosphorus (TP) for Bacillaria paradoxa and Hantzschia amphioxys of G3, and TP and turbidity for N. ovalis and Stephanodiscus invistatus of G4. These results collectively indicate that the distribution of epilithic diatom communities in Korean peninsula was largely effected by water quality and land cover/use.

• 한국토양비료학회지
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• 제50권5호
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• pp.391-400
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• 2017

Italian ryegrass (IRG) is one of the fastest growing grasses available to farmers. It offers rapid establishment and starts growing early in the following spring and has fast regrowth after defoliation. So, IRG can be utilized as the dominant/single species of grass used in a farming system, or to play a role as a large producing pasture and sacrificial paddock. The objective of this study was to develop the use of unmanned aerial vehicle (UAV) for the evaluation of feed value of IRG. For this study, UAV imagery was taken on the Nonsan regions two times during the IRG growing season. We analyzed the relationships between $NDVI_{UAV}$ and feed value parameters such as fresh matter yield, dry matter yield, acid detergent fiber (ADF), neutral detergent fiber (NDF), total digestible nutrient (TDN) and crude protein at the season of harvest. Correlation analysis between $NDVI_{UAV}$ and feed value parameters of IRG revealed that $NDVI_{UAV}$ correlated well with crude protein (r = 0.745), and fresh matter yield (r = 0.655). According to the relationship, the variation of $NDVI_{UAV}$ was significant to interpret feed value parameters of IRG. Eight different regression models such as Linear, Logarithmic, Inverse, Quadratic, Cubic, Power, S, and Exponential model were used to estimate IRG feed value parameters. The S and exponential model provided more accurate results to predict fresh matter yield and crude protein than other models based on coefficient of determination, p- and F-value. The spatial distribution map of feed values in IRG plot was in strong agreement with the field measurements in terms of geographical variation and relative numerical values when $NDVI_{UAV}$ was applied to regression equation. These lead to the result that the characteristics of variations in feed value of IRG according to $NDVI_{UAV}$ were well reflected in the model.

• 환경영향평가
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• 제27권2호
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• pp.181-193
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• 2018

본 연구는 구상나무(Abies koreana) 분포지를 대상으로 AHP (Analytic Hierarchy Process)기법을 적용한 InVEST모델을 사용하여 서식처 질 분석과 탄소고정량 추정을 통한 경제적 가치 평가를 하였다. 구상나무는 국내 고유종으로 장차 국가의 생물 주권 확립에 따라 핵심요소로 작용하고 있음에 따라 구상나무의 보존을 위해 연구대상지를 구상나무의 분포지인 한라산, 지리산, 소백산국립공원으로 선정하였다. InVEST모델 선행연구에서 시사한 한계점인 국내 입력자료가 없어 해외문헌의 값을 차용하여 정확성이 떨어지는 부분을 보완하기 위해 AHP기법을 적용하여 입력자료로 하였으며, 시나리오 분석을 위해 1980, 1990, 2000년을 기준으로 모델링을 하였다. 결과는 한라산국립공원이 가장 큰 서식처 질의 변화양상을 보였으며, 1980년은 $0.96{\pm}0.14$, 1990년은 $0.97{\pm}0.14$, 2000년은 $0.94{\pm}0.17$로 감소하는 것으로 도출되었다. 소백산국립공원의 구상나무의 분포지인 아고산지대의 변화가 가장 큰 곳으로, 서식처 질은 0.98, 0.98, 0.97로 감소하였다. 연구대상지 중 지리산국립공원의 서식처 질은 0.98, 0.99, 0.99로 가장 잘 보존된 곳으로 도출되었다. 그리고 경제적 가치환산 결과, 한라산은 1,928만 달러 손실, 소백산은 803만 달러 손실로 추정되었다. 결과적으로 국내 고유종인 구상나무가 제공하는 생태계서비스의 서식처 질과 경제적 가치추정을 통해 정량적인 값을 도출하였다. 생태계서비스 모델로 특정지역의 서식처 질 분석을 통한 정성적인 변화와 경제적 가치 환산을 통한 정량적인 값의 제시가 가능함을 확인할 수 있었다. 생태계서비스의 가치를 평가를 통해 보존지역의 개발과 같은 외부요인으로부터의 변화예측을 통한 객관적인 평가로 지속가능한 자연자원의 이용과 생태계 보전을 증진하는 방향으로 유도할 수 있는 방안으로 적용이 가능하다고 사료된다.

• 한국습지학회지
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• 제21권1호
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• pp.16-26
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• 2019

동식물의 서식지 제공 및 수문학적 조절 등 다양한 생태계 서비스를 제공하는 습지는 경관 내 습지간의 상호작용을 통해 생태계를 구성한다. 따라서 습지경관에서의 생태계의 리질리언스 등의 기능을 평가하기 위해서는 습지의 동역학적 특성과 더불어 습지간에 형성되는 생태적 연결성 분석이 필요하다. 본 연구에서는 습지를 생태학적 노드로 정의하여 습지 서식종의 분산 모형에 따라 발생하는 습지간 연결을 통해 생태 네트워크를 생성하고 네트워크 분석 방법을 통해 생태 네트워크의 특성을 비교, 분석하였다. 임계거리를 활용한 분산모델 (threshold distance)의 경우 확률적인 분산모델(exponential dispersal kernel, heavy-tailed dispersal model)과 비교하여 국지적인 군집화가 높으나 습지 간의 이동에는 비효율적인 것으로 나타났다. 반면 확률적 분산모델의 경우 국지적인 군집화는 낮게 나타나나 습지 경관 내에서의 이동은 효율적인 것으로 나타남에 따라 분산 모델에 따른 생태 네트워크 특성에 차이가 발생함을 확인하였다. 본 연구는 향후 습지경관 리질리언스 분석을 위한 생태 네트워크 구축의 기초자료로 활용될 수 있을 것으로 사료된다.

• 대한화학회지
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• 제19권5호
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• pp.331-338
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• 1975

크롬산염, 중크롬산염, 요오드산염 및 과요드산염의 중성자포획에 수반하는 크롬-51 및 요오드-128 반조 화학종의 분배를 거름종이 전기영동법으로 검토하였다. 유효반조에너지 및 내부전환의 관점에서 생각하면 중성자 포획원자가 초기분자중에 잔유하고 반조원자에너지가 결정의 적은 범위를 가열하며 소멸된다고 하기 어렵다. 그러나 거름종이 전기영동결과 더 많은 크롬-51 및 요오드-128 반조원자가 어미분자와 결합되어 있음을 알 수 있었다. 잔류율의 관찰결과 반응 이론을 Disorder Model로 설명하였다. 양이온 반경이 클수록 2차 cage를 돌파하는 반조원자의 확율이 높다. 암모늄염중 암모늄이온은 disorder zone에서 환원작용을 하며 잔류율이 낮어졌다. 결정구조에서 자유공간이 크면 잔류율이 낮어졌다.

• 천문학회보
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• 제40권1호
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• pp.60.1-60.1
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• 2015

High energy photons and mechanical energy produced by the process of star formation result in copious FIR molecular and atomic lines, which are important coolants of the system. Photons thermally or mechanically induced could dissociate water in the dense envelope to change relative abundances among the species of O, OH, and H2O. Here we analyze OH emission lines toward embedded young stellar objects (YSOs) observed as part of the Herschel open time key program, 'Dust, Ice, and Gas In Time (DIGIT)' in order to study the physical conditions of associated gas and the energy budget loaded on the OH line emission. According to our analysis of the Herschel/PACS spectra, OH emission peaks at the central spaxel in most of sources, but several sources show spatially extended emission structures. In the extended emission sources, the distribution of OH emission is correlated with that of [OI] emission and extended along the outflow directions. Considering the diversity of source properties, ratios between detected OH lines are relatively constant among sources. In addition, each OH line has strong correlation with bolometric luminosity. In order to determine the physical conditions of YSOs, we adopt several methods for the analysis of the OH lines: rotational diagram, non-LTE LVG analysis, and a 2-D PDR code. From the simple LVG analysis, we find that the thermal solution with the dense ( > $10^7cm^{-3}$) and warm ( ~ 100 K) OH gas reproduces the ratios of detected OH lines. However, our self-consistent PDR 2-D model, which can deal with the IR-pumping effect from the central protostar as well as the warm dust in situ, cannot fit the observational results, suggesting that an irradiated shock model is necessary for a better interpretation.

• 한국환경복원기술학회지
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• 제18권2호
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• pp.19-32
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• 2015

In Korea, significant riparian areas have been developed due to river maintenance projects. Introduction of new riparian facilities can negatively affect wildlife in the riparian areas. This study focuses on selecting core conservation areas for Eurasian Otter(Lutra lutra) to support decision making process for development of riparian areas. For the study, first of all, field data of study site were collected by field surveys. Secondly, stream naturalness was assessed to understand physical environments of the study sites. Thirdly, habitat suitability was assessed using occurrence data of Eurasian Otter and environmental data. Lastly, core areas for conservation was selected by comparing and synthesizing stream naturalness map and habitat suitability map. The selected core areas showed several characteristics. The number of artificial facilities is low in the core areas. Rocks which are preferred by Eurasian Otter to eat and excrete are plentiful in the core areas. Also, the ratio of adjacent farmland is high. Based on the analyses, it is expected that this study can contribute to decision making process for environmental spatial plans to better conserve habitats of Eurasian Otter.