• 제목/요약/키워드: Mountainous areas

검색결과 472건 처리시간 0.027초

금호분지 내 지리관광자원의 자연지리학적 배경 (Physical Geographical Background of Geotourism Resources in Gumho River Basin)

  • 손명원
    • 한국지역지리학회지
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    • 제12권2호
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    • pp.202-214
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    • 2006
  • 본 논문에서는 금호분지를 6개의 지형단위(보현산지, 팔공산지, 비슬산지, 영천분지, 경산분지, 대구분지)로 구획한 후, 각 지형단위 내에 분포하는 지리관광자원의 자연지리학적 배경과 분포의 특성을 고찰하였다. 금호분지 내의 지리관광자원은 지형환경(32개, 78%)을 많이 반영하며, 다음으로 지질환경(7개, 17%)을 반영한다. 보현산지 내에는 3개의 지형자원이 분포하며, 팔공산지 내에는 8개의 지형자원이 분포한다. 비슬산지 내에는 5개의 지형자원과 1개의 문화자원이 분포한다. 그리고 영천분지 내에는 2개의 지형자원과 1개의 지질자원, 1개의 생물자원, 그리고 2개의 문화자원이 분포하는데, 생물자원 1개와 문화자원 1개는 지형환경을 반영한다. 정산분지 내에는 1개의 지형자원과 1개의 생물자원, 3개의 지질자원이 분포하며, 생물자원 1개는 지형환경을 반영한다. 대구분지 내에는 8개의 지형자원과 2개의 지질자원, 3개의 생물자원이 분포하는데, 생물자원 2개는 지형환경의 영향을 많이 받는다.

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산지유역의 돌발홍수 위험지역 평가기법 (An Assessment Method for Hazardous Region of Flash Flood in Mountainous Areas)

  • 이정호
    • 한국산학기술학회논문지
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    • 제11권11호
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    • pp.4629-4634
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    • 2010
  • 홍수방어에 대한 과거의 연구들은 대부분 대규모 하천 유역에 집중되어왔으나, 최근 경제력의 향상을 통한 산악지역으로의 레져영역의 확대는 돌발홍수 발생에 대비한 추가적인 방재활동의 필요성을 증대시키고 있다. 따라서 본 연구에서는 돌발홍수로 인한 인명 및 재산 피해를 최소화하기 위하여 다양한 지표들을 고려하여 산지유역에서의 돌발홍수 발생 위험을 평가하기 위한 기법을 제시하였다. 이를 위해 본 연구에서는 돌발홍수 위험지역을 평가하기 위하여 지역특성, 강우특성 및 지형특성을 평가지표로서 선정하였으며, 이들 요소들의 특성을 평가하여 돌발홍수 경보 시스템 설치를 위한 적정 지점을 평가 및 선정하는 기법을 제안하였다. 제안된 평가 기법은 봉화군에 적용되었으며, 이를 통하여 제안된 기법의 적용 과정을 설명하였다.

Classification of Water Areas from Satellite Imagery Using Artificial Neural Networks

  • Sohn, Hong-Gyoo;Song, Yeong-Sun;Jung, Won-Jo
    • Korean Journal of Geomatics
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    • 제3권1호
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    • pp.33-41
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    • 2003
  • Every year, several typhoons hit the Korean peninsula and cause severe damage. For the prevention and accurate estimation of these damages, real time or almost real time flood information is essential. Because of weather conditions, images taken by optic sensors or LIDAR are sometimes not appropriate for an accurate estimation of water areas during typhoon. In this case SAR (Synthetic Aperture Radar) images which are independent of weather condition can be useful for the estimation of flood areas. To get detailed information about floods from satellite imagery, accurate classification of water areas is the most important step. A commonly- and widely-used classification methods is the ML(Maximum Likelihood) method which assumes that the distribution of brightness values of the images follows a Gaussian distribution. The distribution of brightness values of the SAR image, however, usually does not follow a Gaussian distribution. For this reason, in this study the ANN (Artificial Neural Networks) method independent of the statistical characteristics of images is applied to the SAR imagery. RADARS A TSAR images are primarily used for extraction of water areas, and DEM (Digital Elevation Model) is used as supplementary data to evaluate the ground undulation effect. Water areas are also extracted from KOMPSAT image achieved by optic sensors for comparison purpose. Both ANN and ML methods are applied to flat and mountainous areas to extract water areas. The estimated areas from satellite imagery are compared with those of manually extracted results. As a result, the ANN classifier performs better than the ML method when only the SAR image was used as input data, except for mountainous areas. When DEM was used as supplementary data for classification of SAR images, there was a 5.64% accuracy improvement for mountainous area, and a similar result of 0.24% accuracy improvement for flat areas using artificial neural networks.

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위성영상에서 산악지역의 그림자 추출 (Cast Shadow Extraction of Mountainous Terrain in Satellite Imagery)

  • 손홍규;윤공현;송영선
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 춘계학술발표회논문집
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    • pp.309-312
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    • 2004
  • In mountainous area with high relief, topography may cause cast shadows due to the blocking of direct solar radiation. Remote sensing images of these landscapes display reduced values of reflectance for shadowed areas compared to non-shadowed areas with similar surface cover characteristics. A variety of approaches are possible, though a common step in various active approaches is first to delineate the shadows using automated algorithm and digital surface model (or digital elevation model). This articles demonstrates a common confusion caused by cast shadows

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AHP를 이용한 산지습지 가능지역 평가 (An Assessment of the Potential Area of Mountainous Wetland Using AHP)

  • 문상균;구본학
    • 한국환경복원기술학회지
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    • 제17권1호
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    • pp.27-43
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    • 2014
  • The purpose of this research is to assess potential area of mountainous wetland by GIS and AHP (Analytic Hierarchy Process). Mountainous wetland is topographically located at high altitude, so it's difficult to approach for researchers. And, it's difficult to investigate systematically because of the insufficient information of mountainous wetland. Therefore, it's necessary to study on potential area of mountainous wetland for systematic and efficient investigation. This research selected slope, wetting index, land-cover map and soil map as assessment items indicating environmental characteristics of mountainous wetland and established them by GIS DB. And, spatial value of mountainous wetland for each assessment item was drawn by existing investigation data and overlap analysis of mountainous wetland. Based on the numerical results of each assessment item, a survey was conducted and relative importance for each assessment item was decided by AHP. As the result, slope was the highest as 0.550 and ground coverage was the lowest as 0.083. The subject of this research was Yangsan-si and Ulsan of Gyeongnam and an analysis was conducted for mountainous wetland in those research areas. As the result, all of wetland was distributed in the range of potential area. And, field survey and literature search were conducted for the point that the distribution of mountainous wetland is expected. As the result, mountainous wetland was distributed. Therefore, mountainous wetland should be excavated through the results of this research and it should be helpful for effective investigation as providing information necessary to the following studies on mountainous wetland.

지하수 양수량에 따른 지하수유동 및 포획구간 특성 변화 (Characteristics of Ground Water Capture Zone according to Pumping Rate)

  • 안승섭;박동일;오영훈
    • 한국환경과학회지
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    • 제22권7호
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    • pp.895-903
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    • 2013
  • This study analyzed on characteristics of the ground-water capture zone in coastal areas and mid-mountainous area according to pumping rate. For this study, it targeted Jejudo island where is the volcanic island. To analyze, MODFLOW model and MODPATH model, which are the ground-water flow analysis models, were used. As a result of research, the following conclusions could be obtained. As a result of analyzing influence of a change in pumping time upon length of capture zone, the length of capture zone in coastal area was indicated to be greater in the changing ratio compared to the length of capture zone in mid-mountainous area. Next, in the coastal area, the pumping rate and the capture-zone length are changing similarly. However, in mid-mountainous area, the length of capture zone was indicated to grow when the pumping rate comes to exceed 1,500m3/day. As a result of analyzing influence of a change in pumping time upon capture area, the tendency of a change in the area was indicated similarly in coastal areas and mid-mountainous area. Especially, it could be known that the larger pumping rate leads to the more definite increase in tendency to a change in capture area. Based on this study, it was allowed to be possibly used in the suitable pumping rate in coastal areas and mid-mountainous area of the volcano island in the future. A follow-up research is judged to necessarily analyze the influence of tubular-well group upon capture zone by additionally analyzing a change in capture zone targeting the concentrated tubular well.

Typhoon damage analysis of transmission towers in mountainous regions of Kyushu, Japan

  • Tomokiyo, Eriko;Maeda, Junji;Ishida, Nobuyuki;Imamura, Yoshito
    • Wind and Structures
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    • 제7권5호
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    • pp.345-357
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    • 2004
  • In the 1990s, four strong typhoons hit the Kyushu area of Japan and inflicted severe damage on power transmission facilities, houses, and so on. Maximum gust speeds exceeding 60 m/s were recorded in central Kyushu. Although the wind speeds were very high, the gust factors were over 2.0. No meteorological stations are located in mountainous areas, creating a deficiency of meteorological station data in the area where the towers were damaged. Since 1995 the authors have operated a network for wind measurement, NeWMeK, that measures wind speed and direction, covering these mountainous areas, segmenting the Kyushu area into high density arrays. Maximum gusts exceeding 70 m/s were measured at several NeWMeK sites when Typhoon Bart (1999) approached. The gust factors varied widely in southerly winds. The mean wind speeds increased due to effects of the local terrain, thus further increasing gust speeds.

MONITORING OF MOUNTAINOUS AREAS USING SIMULATED IMAGES TO KOMPSAT-II

  • Chang Eun-Mi;Shin Soo-Hyun
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.653-655
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    • 2005
  • More than 70 percent of terrestrial territory of Korea is mountainous areas where degradation becomes serious year by year due to illegal tombs, expanding golf courses and stone mine development. We elaborate the potential usage of high resolution image for the monitoring of the phenomena. We made the classification of tombs and the statistical radiometric characteristics of graves were identified from this project. The graves could be classified to 4 groups from the field survey. As compared with grouping data after clustering and discriminant analysis, the two results coincided with each other. Object-oriented classification algorithm for feature extraction was theoretically researched in this project. And we did a pilot project, which was performed with mixed methods. That is, the conventional methods such as unsupervised and supervised classification were mixed up with the new method for feature extraction, object-oriented classification method. This methodology showed about $60\%$ classification accuracy for extracting tombs from satellite imagery. The extraction of tombs' geographical coordinates and graves themselves from satellite image was performed in this project. The stone mines and golf courses are extracted by NDVI and GVI. The accuracy of classification was around 89 percent. The location accuracy showed extraction of tombs from one-meter resolution image is cheaper and quicker way than GPS method. Finally we interviewed local government officers and made analyses on the current situation of mountainous area management and potential usage of KOMPSAT-II images. Based on the requirement analysis, we developed software, which is to management and monitoring system for mountainous area for local government.

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Static and quasi-static slope stability analyses using the limit equilibrium method for mountainous area

  • Hosung Shin
    • Geomechanics and Engineering
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    • 제34권2호
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    • pp.187-195
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    • 2023
  • Intensive rainfall during the summer season in Korea has triggered numerous devastating landslides outside of downtown in mountainous areas. The 2D slope stability analysis that is generally used for cut slopes and embankments is inadequate to model slope failure in mountainous areas. This paper presents a new 3D slope stability formulation using the global sliding vector in the limit equilibrium method, and it uses an ellipsoidal slip surface for static and quasi-static analyses. The slip surface's flexibility of the ellipsoid shape gives a lower FS than the spherical failure shape in the Fellenius, Bishop, and Janbu's simplified methods. The increasing sub-columns of each column tend to increase the FS and converge to a steady value. The symmetrical geometric conditions of the convex turning corners do not indicate symmetrical failure of the surface in 3D analysis. Pseudo-static analysis shows that the horizontal seismic force decreases the FS and increases the mass volume at the critical failure state. The stability index takes the FS and corresponding sliding mass into consideration to assess the potential risk of slope failure in complex mountainous terrain. It is a valuable parameter for selecting a vulnerable area and evaluating the overall risk of slope failure.

유출특성을 고려한 산지지역의 물수지 평가 - 제주도 표선유역을 중심으로 - (Assessment of Water Balance Considering Runoff Characteristics in the Mountainous Area of Pyosun Catchment in Jeju Island)

  • 송성호;안중기;이규상
    • 한국환경과학회지
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    • 제24권4호
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    • pp.505-514
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    • 2015
  • The grid-based water balance of watershed scale was assessed in the mountainous area of Pyosun catchment in Jeju Island after analyzing precipitation, evapotranspiration, and runoff from January 2008 to December 2013. The existing results of direct runoff, evapotranspirtion, and groundwater recharge comparing to precipitation were presented 22.0%, 25.6%, and 52.4%, respectively, in Pyosun catchment. However, this study indicated each component shows 14.5%, 24.2%, and 61.0%, respectively, in the mountainous area of Pyosun catchment. Therefore, groundwater recharge rate in the mountainous area appears higher than 10% comparing to the overall catchment. It would be analyzed that the amount of direct runoff is relatively small. Moreover, this difference could be generated because of the spatial discontinuities in the process of estimating the total amount of precipitation in the mountainous area. Therefore, the grid-based spatial analysis to maximize the spatial continuity would be useful for providing a more reasonable result when the total amount of water resources are evaluated in mountainous areas in the future.