• Title/Summary/Keyword: SLOPE ASPECT

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Changing of Vegetation Coverage through Elapsed Years on Cutting Slope in Forest Roads (시간경과에 따른 임도 절토비탈면의 식생피복도 변화)

  • Jeon, Kwon-Seok;Ma, Ho-Seop
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.7 no.3
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    • pp.14-25
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    • 2004
  • The purpose of this study was investigated to the change of vegetation coverage by elapsed years on the cut slope of forest road in Jinju-si. The results obtained could be summarized as follows; The plant coverage on the cut slope of forest road was decreased hastily in first and second year after seeding. The plant coverage on the cut slope of forest road was increased as growth of seed-sprayed from third year. But the plants were began to competition with between sprayed seeds and invaded plants from third to fifth year after seed-spray. The numbers of invading plants were gradually increased as 581 individuals from sixth year after seed-spray. The cut slopes of the forest roads turned to a good site condition for growing of invasion plants. And also the total coverage on cut slope of forest roads by invading of surrounding plants was increased more. It showed that plant invasion on cut-slopes of forest roads would be mostly influenced by surrounding plants. The number of surrounding plants on the cut-slopes of forest roads was 59 species, and the number of invading plants showed 65 species. The invading species were high in order of Boehmeria tricuspis, Oplismens undulatifolius, Miscanthus sinensis var. purpurascens, Erechtites hieracifolia and Artemisia princeps var. Orientalis In the stepwise regression analysis, main factors affecting the coverage of vegetation on the cut-slopes of forest road showed in order of elapsed years, gravel contents(30~50%), middle, sandy loam, sandy clay-loam, soil hardness, aspect(NS), concave(凹) type and gravel contents(15~30%).

The Distribution and Geomorphic Change of Debris Slope at Ongjeom-ri in Cheongsong-gun (청송군 옹점리 일대 암설 사면의 분포와 지형 변화)

  • Lee, Gwang-Ryul;Park, Han-San
    • Journal of the Korean Geographical Society
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    • v.45 no.3
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    • pp.360-374
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    • 2010
  • The distributions, factors, and vegetation covers of debris slopes and changes of debris at the eastern Ongjeom-ri, Cheongsong-gun are analyzed. The important factors influencing on the developments of the slopes are felsites having advantages to the developments of cliffs and supply of enough debris, and the relatively long days below zero temperatures promoting the physical weathering processes. The distributional areas of the slopes at southern and western slopes are more extensive than those of northern and eastern slopes due to the active water evaporation by high insolation. The Ga area at eastern Ongjeom-ri has experienced the steady decreases of area of the slopes due to the vegetation covers and shows the increasing rates of vegetation covers of $431.0m^2/yr$ as averaged values. However, it is estimated at the Na area using terrestrial LIDAR that 1 or 2 debris were moved or displaed per year in slope.

Effects of Forest Environmental Factors and Forest Road Structures on the Stability of Forest Road in Granite Areas (화강암지역의 산림환경 및 도로구조인자가 임도의 안정성에 미치는 영향)

  • Yim, Byung-Jun;Ma, Ho-Seop
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.2 no.3
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    • pp.83-92
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    • 1999
  • To investigate the influence of forest road characteristics and site conditions on the stability of forest-road in granite area, four forest roads had been selected in Kyongbuk regions. The total of 13 road characteristic variables were evaluated by the discriminant analysis. The factors influencing the stability of forest road were bed rock, slope length, coverage, hardness, side-ditch erosion and road width. But aspect and soil texture were not significant for the stability in this area. In the correlation between forest environment and road structure, hardness and bed rock was highly significant in stability group, and coverage and side-ditch erosion was highly significant in instability group. 75 of 175 segments were instable whereas the others were stable. The centroids value by discriminant function in the stability and instability were estimated to 3.0585 and -1.9116, respectively. The stability criterion of forest road was discriminated from the centroids value of the each group. The main factors contributing the stability of forest road were significant in order of side-ditch erosion, coverage, soil texture, elevation, gradient, slope length and construction year. The prediction rate of discriminant function for stability evaluation of forest road was as high as 97.44%. In conclusion, the forest road structure factors such as length, coverage and slope gradient were controlled by construction techniques. If the factors like those should be considered in design, construction and forest road management, the stability of forest road may increase more. And also, it is necessary to take slope protection measures like small terraces and retaining walls for stability of cut slope.

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Characteristics of Habitat-using of Siberian Roe Deer in Seoraksan(Mt.) National Park (설악산국립공원 지역의 노루 서식지 이용 특성에 관한 연구)

  • Park, Yong-Su;Lee, Woo-Shin
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.17 no.1
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    • pp.91-109
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    • 2014
  • This study was conducted to obtain the basic research about Siberian roe deer (Capreolus pygargus), and to establish a conservation area into Seoraksan(Mt.) National Park, South Korea. We recorded Siberian roe deer field signs (bedding sites, feeding areas, feces and tracks etc), and habitat variables such as nearest distance to the watercourse, trails, slope, aspect, forest type and land cover etc. from Jan. 2006 to Dec. 2007 in Seoraksan(Mt.) National Park. According to the research of habitat characteristics of Siberian roe deer inhabited in Seoraksan(Mt.) National Park preferred mixed forest consisted of aged forest and middle-aged forest on the gentle slope which was close to hydrosphere in the middle elevation area of altitude of 400~600m above sea level in Seoraksan(Mt.) National Park. The results indicated that Siberian roe deer appeared to prefer south slope or north slope during the snow season and west or east slope during the non-snow season. The area of most suitable habitat for Siberian roe deer in Seoraksan(Mt.) National Park was $128.5km^2$ (32% of the total area) followed by $244.3km^2$ buffer area (62.2% of the total area), and $22.9km^2$ unsuitable habitat area (5.8% of the total area), which means environmentally unsuitable habitat for Siberian roe deer was rare in Seoraksan(Mt.) National Park. Thus, the area classified as major area in Seoraksan(Mt.) National Park appeared to be most important for the protection of Siberian roe deer.

Assessment of the Effect of Digital Dlevation Model(DEM) Resolution on Simulation Results of the Physical Deterministic Lumped Parameters Hydrological Model (수치표고모형(DEM)의 해상도가 물리 결정 일괄 매개변수 수문모형의 모의 결과에 미치는 영향 평가)

  • Kim, Man-Kyu;Park, Jong-Chul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.11 no.3
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    • pp.151-165
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    • 2008
  • Ground slope and aspect are important parameters for physical deterministic water balance models like BROOK90 or hydrological models which attempt to calculate evapotranspiration, snowmelt, and net radiation. This study constructs a Digital Elevation Model(DEM) and examines how DEM resolution can change the average ground slope and aspect of a river basin and attempts to evaluate the effects on simulation results of BROOK90, a physical deterministic water balance model. The study area is Byungcheon river basin in Korea. DEM has been constructed using a 1:25,000 digital map with the methods of TIN and Topo To Raster. The total of 20 DEMs with 10m~100m resolution have been constructed, with a 10m interval. It was found that the higher the DEM resolution, the steeper the average ground slope value of the Byungcheon river basin. In turn, the direct solar radiation of a hilly area in the model increased the evapotranspiration and reduced the stream runoff in the Byungcheon river basin. On the other hand, a lower DEM resolution tends to move the average aspect from southeast to south in the Byungcheon river basin. Accordingly, it was found that stream runoff was reduced and evapotranspiration increased.

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Application of Hydrological Monitoring System for Urban Flood Disaster Prevention (도시홍수방재를 위한 수문모니터링시스템의 적용)

  • Seo, Kyu-Woo;Na, Hyun-Woo;Kim, Nam-Gil
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.1209-1213
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    • 2005
  • It reflects well feature of slope that is characteristic of city river basin of Pusan local. Process various hydrological datas and basin details datas which is collected through basin basis data. weather satellite equipment(EMS-DEU) and automatic water level equipment(AWS-DEU) and use as basin input data of ILLUDAS model, SWMM model and HEC-HMS model In order to examine outflow feature of experiment basin and then use in reservoir design of experiment basin through calibration and verification about HEC-HMS model. Inserted design rainfall for 30 years that is design criteria of creek into HEC-HMS model and then calculated design floods according to change aspect of the impermeable rate. Capacity of reservoir was determined on the outflow mass curve. Designed imagination reservoir(volume $54,000m^3$) at last outlet upper stream of experiment basin, after designing reservoir. It could be confirmed that the peak flow was reduced resulting from examining outflow aspect. Designing reservoir must decrease outflow of urban areas.

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Temperature Variation by Terrain Using Multitemporal TM Band 6 and DEM(With Seoul City Area) (다시기 TM 밴드 6와 DEM을 이용한 지형별 온도변화(서울시 영역을 대상으로))

  • 박민호
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.11a
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    • pp.203-210
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    • 2004
  • The average temperatures by the land cover class, by the elevation extent, by the slope and by the aspect have been calculated using multitemporal Landsat TM band 6 and DEM. For this, the TM band 6 data from October 21, 1985, June 2, 1992, September 1, 1996, May 7, 2000 and the 28.5m x 28.5m grid elevation data of Seoul have been used. From the varying curve of the average land surface temperature by the elevation extent, the presence of the atmospheric inversion phenomenon and the scope of the inversion layer can be inferred. Especially, the average land surface temperature by the aspect can be effective for deciding a road line. For these reasons, it is expected that temperature estimation using remote sensing data shall be effective for the survey of heat damage, environmental temperature monitoring, and urban and environmental Planning usage.

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Saturation Boiling Heat Transfer on a Heated Surface With Impinging Water Jet (충돌수분류에 의한 포화비등열전달)

  • Ohm, Ki-Chan;Seo, Jeong-Yun
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.15 no.2
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    • pp.182-187
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    • 1986
  • Experimental measurements of the heat transfer and heat flux to a jet impinging on a heated surface were obtained in the nucleate boiling regimes. Tes-variables were jet at velocity and aspect ratio ($b/\ell$) of the heated surface. A slope of nucleate boiling curve increased with increasing the aspect ratio of the heated surface, namely approaching a rectangular square, and it is shown that surface tension has an important role for the onset of nucleate boiling heat transfer. A generalized correlation of the jet nucleate boiling heat transfer. A generalized correlation of the jet nucleate boiling heat transfer was found using a pi theorem.

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On the Determination of Slope Stability to Landslide by Quantification(II) (수량화(數量化)(II)에 의한 산사태사면(山沙汰斜面)의 위험도(危險度) 판별(判別))

  • Kang, Wee Pyeong;Murai, Hiroshi;Omura, Hiroshi;Ma, Ho Seop
    • Journal of Korean Society of Forest Science
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    • v.75 no.1
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    • pp.32-37
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    • 1986
  • In order to get the fundamental information that could be useful to judge the potentiality of occurrence of rapid shallow landslide in the objective slope, factors selected on Jinhae regions in Korea, where many landslides were caused by heavy rainfall of daily 465 mm and hourly 52mm in August 1979, was carried out through the multiple statistics of quantification method (II) by the electronic computer. The net system with $2{\times}2cm$ unit mesh was overlayed with the contour map of scale 1:5000. 74 meshes of landslides and 119 meshes of non-landslide were sampled out to survey the state of vegetative cover and geomorphological conditions, those were divided into 6 items arid 27 categories. As a result, main factors that would lead to landslide were shown in order of vegetation, slope type, slope position, slope, aspect and numbers of stream. Particularly, coniferous forest of 10 years old, concave slope and foot of mountain were main factors making slope instability. On the contrary, coniferous forest of 20-30 years old, deciduous forest, convex slope and summit contributed to the stable against Landslide. The boundary value between two groups of existence and none of landslides was -0.123, and its prediction was 72%. It was well predicted to divide into two groups of them.

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The Morphological Change by Slope Erosional Processes in the Dokdo Seamount (독도해산의 사면침식으로 인한 지형변화)

  • Kang, Ji-Hyun;Sung, Hyo-Hyun;Park, Chan-Hong;Kim, Chang-Hwan;Jeong, Eui-Young
    • Journal of the Korean Geographical Society
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    • v.43 no.6
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    • pp.791-807
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    • 2008
  • The purpose of this study is to analyze landform characteristics and geomorphic processes in Dokdo seamount. For geomorphic analysis, bathymetry data were collected by multi-beam echosounder and the seismic survey was also conducted. Through the detailed analysis of depth, slope, aspect and erosional landform, Dokdo Seamount is characterized by a flat or gently sloping top of $2^{\circ}$ or less and seamount slope with $14{\sim}40^{\circ}$ gradient. There are protrusion of landform around the Dokdo on top of the Dokdo seamount. It is inferred that the features are formed by collapsed debris deposits or remained bedrocks by differential erosion in the past. The massmovement topography including slump and slide is shown on seamount slope with $14{\sim}40^{\circ}$ gradient. In addition, gullies with various length are developed on the Dokdo seamount slope. Slope erosional processes occur more actively along the submarine gullies on the Dokdo seamount. It is inferred that the massmovement processes on the slope of Dokdo seamount are related to earthquake activities and evolution of submarine volcano. Consequently, slope of the Dokdo seamount has retreated by erosional processes of mass-movement and submarine gullies.