• 공업화학
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• 제18권2호
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• pp.126-129
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• 2007

원할한 교통망 요구에 따라 도로의 확충이 요구되고, 산악지형이 많은 국토의 특성을 고려할 때 터널이 많이 요구된다. 이러한 터널 공사에서 많은 오염 물질은 천공, 발파, 버럭처리 숏크리트 과정에서 발생되었다. 특히 급기 팬만을 가동 할 경우 분진과 같은 오염물질은 발파 후 4 h이 지나도록 $5000{\mu}g/m^3$ 이상을 나타내었으며, 발파 직후에는 높은 분진 농도로 인하여 30 min 이상 작업을 중단할 수밖에 없었다. 또한 건식 집진기를 가동 할 경우에도 일정 시간 까지는 분진의 제거는 가능하였으나 발파 후 3 h이 지나면 집진 효율이 없는 것으로 나타났다. 본 논문 에서는 분진입자들의 거동과 분진제거장치의 사용에 대해 중점적으로 연구하였다. 또한 건식집진기와 습식집진기의 사용에 있어 각각에 대한 집진제거효율을 비교검토하는 것이 매우 중요하다 결론을 얻었다.

• Journal of Forest and Environmental Science
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• 제30권1호
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• pp.152-160
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• 2014

The purpose of this study is to investigate and analyze the physical characteristics and tranquility of the valleys located in Gangwon region. For this study we analyzed the field survey data 135 valleys using GIS. The elements for measurement of tranquility were divided into visual elements including terrain, objects, forest, water and auditory elements including noise. These elements were divided further into positive and negative factors. The weight of each element and item was calculated by applying the AHP method. The results of this study are as follows. The length of the valley ranged from 126 m to 17 km, and the elevation ranged from 40 m to 1,800 m. Type of mixed forest was common in the valleys. The depth of the water was over 20 cm in 83% of the total area and most of the water was in good condition in visual quality. Regarding the positive factors of tranquility, the weighted scores of the objects, waterfall sounds and visual transparence of the water were of relatively high value. Relatively high values were also shown in closed and curved topography in the landform, forest type and natural forests. In the negative factors, the weights of the objects and forest elements had high values. Within the facility groups, facility of the river produced a considerable negative. After applying the index of tranquility, the natural physical attributes affected the tranquility value, more than the manmade structures to a much greater degree.

• 건축역사연구
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• 제10권4호
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• pp.7-21
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• 2001

This study is to analyze site layout traditional government office building focused on Chonui-hyon(全義縣) in Chungchong province with Chungchong-do regional maps(忠淸道地方地圖) and Eupjis(邑誌, topography) being compiled in the late Chosun dynasty. The conclusion of analysis can be summarized as follows; 1. Chonui-hyon(全義縣) in Chosun dynasty is gone with a planning principle of the capital city(Han-Seong, 漢城) with disposing Sa-Ji-Dan(社稷壇) and Gaek-Sa(客舍), which are placed to the left and right of Eupchi(邑治), and it is followed in the wake of the spatial structure of Chosun dynasty palace with disposing Dong-Heon(東軒) in front, Nae-A(內衙) at the back of it, or from side to side, also by the Dong-Heon of the center, with organizing each facility around it. 2. Dong-Heon and Gaek-Sa of Chonui-hyon is passed through three step gate, Mun-Ru(門樓), Woi-Sammun(外三門), Nae-Sammun(內三門), from Hong-Salmon(紅門), and are shown hierarchy by haying been placed at the end of approach axis. 3. Dong-Heon can be disposed by Feng-Shui(風水) which have influence on the southeast direction with Jin-San(鎭山) and An-Dae(案對), on the other hand, Gaek-Sa can be disposed by symbolic of the authority of a king. 4. Site layout by function of provincial government office is provided into four ferrite, Dong-Heon, Gaek-Sa, Nae-A, practical business territory, and eve territory is organized by official institution on a social position to radiation, by the compositive axis to be made Woi-Sammun Nae-Sammun Dong-Heon Nae-A 5. Approach process of Chnui-hyon government office is three door system similar to Kam-Young(監營) in a different way two door system in most provincial government office, also approach axis is formed by bending.

• 환경영향평가
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• 제8권3호
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• pp.61-76
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• 1999

For the effective management of urban forest, a variety of informations on urban forest needs to be accurately measured and effectively used in decision-making processes. This study aims at developing an urban forest management system with reference to GIS and making it possible to effectively manage urban forests. A detailed forest type map were constructed with the help of aerial photograph and terrestrial inventory. A geographical map in terms of slope, aspect and altitude were also prepared by Digital Elevation Model(DEM). A soil type map containing chemical characteristics were also made through soil analysis. These thematic maps which contain informations on forest type, geography and soil were digitalized with reference to GIS, and an urban forest management system of user interface were developed. With the help of this urban forest management system, various spatial and attribute informations which need for urban forest management could be easily used in decision-making processes in relation to urban forest.

• The Korean Journal of Ecology
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• 제25권2호
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• pp.83-91
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• 2002

내연산의 삼림식생을 대상으로 ZM 식물사회학적 방법에 의해 군락단위 및 그 하위 단위를 분류하고, 분류된 각 단위와 환경사이의 상관관계를 서열법으로 해석하여 내연산 산림식생관리를 위한 기초자료를 제공할 목적으로 본 연구를 수행하였다. 군락단위는 신갈나무군락, 굴참나무군락, 소나무군락, 서어나무군락, 느티나무군락이 구분되었고, 하위단위는 철쭉꽃군과 참회나무군, 굴참나무군락에서 우산나물군, 털조록싸리군 및 찰피나무군, 느티나무군락에서 까치박달군과 고욤나무군이 각각 세분되었다. 따라서 내연산 일대의 산림은 5개군락, 7개군으로 총 9개의 식생단위로 분류되었다. CCA 방법으로 식생과 환경사이의 상관관계 분석 결과 내연산 지역의 식생단위는 해발과 가장 높은 상관관계가 있는 것으로 나타났다. 신갈나무군락의 철쭉꽃군과 참회나무군은 해발고와 지형이 높은 곳과 노암율이 낮은 곳에 각각 분포하는 경향이 있다. 한편 느티나무군락은 신갈나무군락과 역의 관계로 나타났다. 앞으로 산림식생관리시 특히 계곡림에 대해서는 교목층의 우점종들이 상관적으로 이질적인 모습을 하고 있더라고 하나의 관리단위로 고려되어야 할 것으로 판단되었다.

• 한국환경과학회지
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• 제12권2호
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• pp.93-100
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• 2003

In most mountainous parts of the temperate zone of Japan along the Pacific Ocean, some climatic climax forests, whose main dominant species is Fagus crenate, F. japonica or Quercus mongolica var. grosseserrata, are distributed. In the riparian regions of the zone, however, there appear summer green forests composed of the different species from the climatic climax forests. Climate plays an important role in determining the overall distribution of vegetation, but some environmental factors, i.e., topography, soil type, soil moisture content, etc. have a great influence on vegetation formation. Riparian forests seem to be controlled by various geomorphologic disturbances, such as landslide, soil erosion and accumulation. The study aims to present the relationships among vegetation, soils and landforms in the process of determining riparian forests dominated by Fraxinus platypoda and Pterocarya rhoifolia establishment in the mountainous region of central Japan. The study area extends an area of 302 ha with a range of elevation between 925 m and 1,681 m at the Chichibu mountains. The landforms were corditied at sampling grids (25 $\times$ 25 m, n = 4,843) using a hierarchical system, and a brief description of the forest soil classification was also given. The mutual relationship analysis indicated that forest soils and landforms play a significant role in determining the geomorphological process of riparian forest, and shaping the ultimate pattern of vegetation. At the study area, riparian forests were mainly found on the $B_E$ forest soil type and steep slopes ( > 30$^{\circ}$) at convex slopes along the streams. On the other hand, the direction of slopes did not have a significant impact on the establishment of the riparian forests. A mosaic of patchy distribution of those riparian forests on the slightly wetter $B_E$ forest soil type was one of the characteristic features of the study area. This particular soil which contained large talus gravels was found on the land formed by erosion and deposition of landslide.

• 한국지구과학회지
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• 제23권1호
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• pp.1-14
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• 2002

The land-cover of two regions of South and North Korea included in one Landsat TM scene was investigated by comparing different seasons and different band data over the multiple land-cover types. The relationships between the intensities of two bands in the 2-D plot are mainly linear in band2 versus band1 and band3 versus band1, polygonal sporadic in band5 versus band1 and band7 versus band1, and almost tri-polarized in band4 versus band3. The 2-D plot of band4/band3 shows the best capability to discriminate different main land-cover such as water, vegetation and dry soil. Some discriminations are not clear between city and dry field, or mountain and plain field in the scene of September. The digital number data of band4 from vegetated zones show stronger reflectance in September rather than April, while other band values tend to be lager in April than in September over each land-cover. NDVI presents high value in both regions in September. However the image of Wonsan area in April suggests weak vigor of vegetation in comparison with Cholwon area. Band ratios are very effective in eliminating the influence of the complex topography. The proper pairing of the band ratio improved the discrimination capability of the land-cover; band5/band2 for dry soil, band4/band3 for vegetation and band1/band7 for the water. The RGB combination of the three band ratio pairs showed the best results in the discrimination of the land-cover of Wonsan, Cholwon and even the Demilitarized Zone.

• 한국수소및신에너지학회논문집
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• 제22권4호
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• pp.488-494
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• 2011

Gasket plays an important role on sealing of the polymer electrolyte membrane fuel cell (PEMFC) stack. Stack requires gaskets in each cell to keep the hydrogen and air/oxygen within their respective regions. The failure of the gasket creates the problems of fuel leakage, mixing, damage on parts and can be a direct reason for the degrading the efficiency of fuel cell. The purpose of this paper researches on how mechanical properties of EPDM gasket in PEMFC are changed after long-term operations. The EPDM (ethylenepropylene-diene monomer) gaskets are obtained from the stack after long-term operations. DMA (dynamic mechanical analysis) is conducted to access the change of mechanical properties of the EPDM gasket. SEM/EDS (scanning electron microscope/energy dispersive spectroscopy) was used to show the surface topography and chemical characterization on the sample surface.

• 한국수산과학회지
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• 제38권1호
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• pp.29-38
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• 2005

The distributions of fish larvae and juveniles from the East China Sea, Yellow Sea and near Tsushima Island were investigated in Spring using the Maruchi (1994-1995) and Unagi (1996-1997) nets. A total of 94 species of fish larvae and juveniles belonging to 49 families under 17 orders were identified, of which Engraulis japonicus was dominant in every year except 1995 where Trachurus japonicus was dominant. Cluster analysis based on abundance and species composition by sampling stations (St.) revealed that the similar stations formed an arcuate group from Tsushima Island to southern Jeju Island in 1994, and from the Yellow Sea to southern Jeju Island in 1996. We concluded that these patterns resulted from the influence of the Tsushima Current prevailing in the east, and the Chinese Continental Waters and/or Hwanghae Cold Waters prevailing in the west, with Jeju Island exerting an influence in the centre. The diversity and composition of St. 97-3 and St. 97-5, both located where the Tsushima Current splits from the Kuroshio Current, was greatly different despite their close proximity. However, the former is located on the continental shelf, with the latter on the continental slope. This suggested that both topography and the Kuroshio Current have the most influence on the distribution of fish larvae and juveniles in this region. Furthermore, the weak Hwanghae Cold Waters of 1997 may have also limited the mixing of fish larvae and juveniles between the two stations.

• Ocean and Polar Research
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• 제36권2호
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• pp.87-101
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• 2014

Recently, more attention has been paid to the geomorphological changes in the Nakdong River Estuary, because those changes are caused by artificial activities including weirs, reclamation and construction. In order to analyze quantitatively the recent geomorphological variability in the Nakdong River Estuary, we surveyed the depth and elevation of submarine topography near Jinwoodo and Sinjado from March 2007 to February 2012. A statistical method (based on Digital Shoreline Analysis System) and an Empirical Orthogonal Functions method were used to evaluate the morphological changes. According to the statistical variables (DCE, NDC, EPR, LRR), the highest amount and rate of accumulation were recorded around the Gadeokdo whereas the greatest amount of erosion appeared around the coast off the eastern part of Sinjado. In particular, a dynamic variation of morphology was clearly observed in the vicinity of the sub-tidal channel located between Jinwoodo and Sinjado, which seems to be attributable to channel migration. As a result of the EOF method, the first mode (48.7%) is most closely related to the pattern of morphological variability that might be associated with the westerly movement of sediment by longshore current. The spatial variability of the second mode (16.6%) was high in the shoreface of Sinjado, showing a 4-year periodicity of temporal variability. The strong correlation (coefficient 0.73) between the time coefficient and suspended sediment discharge from Nakdong River emphasizes the role of sediment discharge to deposition in this area. The spatial variability of the third mode (11.3%) was distributed mainly around the coast off the eastern part of Sinjado, which is related to the movement of the coastline of Sinjado. Based on the last 5 year's data, our results suggest that the study area is characterized on the whole by a depositional pattern, but the extent of sedimentation is different locally.