• Title/Summary/Keyword: aspect and slope analysis

Search Result 203, Processing Time 0.032 seconds

The Seepage Behaviour and Stability of Extension Embankment by Unsteady State Seepage (비정상침투에 의한 증축제체의 침투거동과 안정성)

  • Shin, Bang-Woong;Bae, Woo-Seok;Lee, Jong-Kyu;Kang, Jong-Beom
    • Journal of the Korean GEO-environmental Society
    • /
    • v.2 no.1
    • /
    • pp.57-65
    • /
    • 2001
  • In this study, the seepage behavior and the stability of the extension embankment were estimated for three cases the permeability coefficient of an extension part and the rising velocity due to the rainfall of flood period. In parallel flow condition, the unstability of the slope due to embankment erosion was examined by analyzing the variation of seepage line by the seepage modeling tests and FEM analysis, and the stability of the embankment slope accompanied by the sudden rise of the water level after the flood. The seepage behavior of extension embankment indicates that the larger permeability of the extension part the longer initial seepage distance, and the exit point from embankment slope is gradually increased, and then shows unstable seepage behavior that occurs a partial collapse as safety factor decreases with time. It is because of the increment of exit points due to variation of seepage line and rising velocities of water level. Also, the collapse aspect of embankment slope shows that the increment rising velocities of water level causes the increment collapse height and depth.

  • PDF

Distribution of Subgenus Lycoctonum in Korea: Analysis and Verification by GIS (한국산 진범 종집단의 서식상황: GIS를 이용한 분석과 검증)

  • Lee, Soo-Rang;Jeong, Jong-Chul;Park, Chong-Wook
    • Spatial Information Research
    • /
    • v.15 no.2
    • /
    • pp.135-146
    • /
    • 2007
  • The purpose of this study was to ascertain and analyze environmental factors of subgenus Lycoctonum in Korea for conservation and management of rare high land plant species by GIS. We derived the habitat model of Lycoctonum from GPS coordination, habitat factors and digital topology maps. Suitable altitude fur the subgenus Lycoctonum is from 470m to 1320m, and northern slopes(between 15.5 and 36 degrees) are ideal for the Lycoctonum populations. In addition to altitude, slope and aspect, deciduous forest and approximation to water source were found as important factor. Using GIS and the Lycoctonum habitat model, we overlaid elevation, aspect, slope and land cover layers and analyzed buffer from the water source on two topology maps, Yang-Soo and Mock-Dong. After making prediction map for Lycoctonum habitat, we verified the existence of Lycoctonum populations on the predicted sites through field survey. Through this research, we're convinced that GIS software is powerful tool for plants conservation, such as finding unknown habitat or selecting alternative habitat.

  • PDF

Development of Landslide Hazard Map Using Environmental Information System: Case on the Gyeongsangbuk-do Province (환경정보시스템을 이용한 산사태 발생위험 예측도 작성: 경상북도를 중심으로)

  • Bae, Min-Ki;Jung, Kyu-Won;Park, Sang-Jun
    • Journal of Environmental Science International
    • /
    • v.18 no.11
    • /
    • pp.1189-1197
    • /
    • 2009
  • The purpose of this research was develop tailored landslide hazard assessment table (LHAT) in Gyeongsangbuk-do Province and propose building strategies on environmental information system to estimate landslide hazard area according to LHAT. To accomplish this purpose, this research investigated factors occurring landslide at 172 landslide occurred sites in 23 city and county of Gyeongsangbuk-do Province and analyzed what factors effected landslide occurrence quantity using the multiple statistics of quantification method(I). The results of analysis, factors affecting landslide occurrence quantity were shown in order of slope position, slope length, bedrock, aspect, forest age, slope form and slope. And results of the development of LHAT for predict mapping of landslide-susceptible area in Gyeongsangbuk-do Province, total score range was divided that 107 under is stable area(IV class), 107~176 is area with little susceptibility to landslide(III class), 177~246 is area with moderate susceptibility to landslide(II class), above 247 area with severe susceptibility to landslide(I class). According to LHAT, this research built landslide attribute database and made 7 digital theme maps at mountainous area located in Goryeong Gun, Seongju-Gun, and Kimcheon-City. The results of prediction on degree of landslide hazard using environmental information system, area with little susceptibility to landslide(III class) occupied 65.56% and severe susceptibility to landslide(I class) occupied 0.51%.

A PRODUCTION METHOD OF LANDSLIDE HAZARD MAP BY COMBINING LOGISTIC REGRESSION ANALYSIS AND AHP (ANALYTICAL HIERARCHY PROCESS) APPROACH

  • Lee, Yong-Jun;Park, Geun-Ae;Kim, Seong-Joon
    • Proceedings of the KSRS Conference
    • /
    • v.2
    • /
    • pp.547-550
    • /
    • 2006
  • This study is to suggest a methodology to produce landslide hazard map by combining LRA (Logistic Regression Analysis) and AHP (Analytic Hierarchy Program) Approach. Topographic factors (slope, aspect, elevation), soil drain, soil depth and land use were adopted to classify landslide hazard areas. The method was applied to a 520 $km^2$ region located in the middle of South Korea which have occurred 39 landslides during 1999 and 2003. The suggested method showed 58.9 % matching rate for the real landslide sites comparing with the classified areas of high-risk landslide while LRA and AHP showed 46.1 % and 48.7 % matching rates respectively.

  • PDF

A Study on Calculation of Readjustment Height of Urban Region by Geo-spatial Information System - Focused on the Region of YOUNGDO-GU, PUSAN- (지형공간정보체계를 이용한 도시지역의 정지표고 산정에 관한 연구 -부산시 영도구 지역을 중심으로-)

  • 박운용;차성렬;신상철
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.12 no.1
    • /
    • pp.119-129
    • /
    • 1994
  • Geo-spatial information system covers a wide range of applications and technologies and is of great potential interest to many users in government, industry and science. In many civil engineering problems it is necessary to model a landform in order to be able to removed or to be brought in to make the site ready for the proposed developed. The earthwork volume, could be calculated by the trapezoidal formula, Simpson's 1/3 and 3/8 rules. And slope is defined by a plane tangent to the surface as modelled by the digital terrain model at any given point and comprises two components namely, gradient, the maximum rate of change altitude, and aspect, the compass direction of this maximum rate of change. The thesis is the earthwork volume could be counted, readjustment height, slope and aspect analysis of various derived products can be obtained form geo-spatial informations.

  • PDF

Development of a Habitat Suitability Index for Vulpes vulpes (여우(Vulpes vulpes)의 서식지 적합성 지수(HSI) 모델 개발)

  • Ou, Yeokyung;Lee, Sangdon
    • Journal of Environmental Impact Assessment
    • /
    • v.31 no.4
    • /
    • pp.265-270
    • /
    • 2022
  • With the implementation of the fox restoration project, the number of foxes released into nature are increasing; therefore, in the future, foxes will be dispersed to other areas and will appear in human habitats. In this study, the habitat suitability index (HSI) of foxes was developed to predict and prepare for the effects. After extracting major environmental variables through literature research and GIS analysis, 5 suitability indices (SIs) were constructed. The forest physiognomy, slope, aspect, distance from water source, and distance from road are the main variables, and the arithmetic average value by giving twice the weight to the forest physiognomy is the HSI result. As a result of comparing with the data from the Natural Environment Survey, it is found that the fox coordinates have an average HSI value of 0.64, and the probability of appearance is high when it is 0.53 or higher. Using the results of this study, it is expected to be able to predict the distribution of foxes in advance, to use them as basic data for future restoration plans, or to identify the distribution of the species and the reduction plan in future environmental impact assessments.

Finite Element Analysis for the Effects on the Stiffness of the Embankment and Sandmat on the Deformation Property and the Safety of Road Embankment (성토체 및 모래매트의 강성이 하부지반의 변형과 성토체의 안전에 미치는 영향에 대한 유한요소해석)

  • Bae, Woo-Seok;Kim, Jong-Woo;Kwon, Young-Cheul
    • Journal of the Korean Society of Safety
    • /
    • v.22 no.4
    • /
    • pp.57-65
    • /
    • 2007
  • Effects on the stiffness of the embankment and sandmat on the construction safety of road embankment was investigated in this study by the numerical experiments using FEM. Two points was mainly focused in this study especially. First the deformation characteristics by the change of the stiffness of sand mat and embankment was investigated by the analyzing the consolidation settlement at the center of the embankment and the lateral displacement at the toe of the embankment. And, the effect of the stiffness on the stress distribution characteristics was also investigated in this study. Furthermore, slope stability analysis was carried out to gain the safe factor by change the stiffness of the sandmat and the embankment. The objective of the study is supplying the result of the numerical experiments for the geotechnical engineers who use the FEM for the safety design of the soil structures. As a result, the stiffness of the superstructures greatly affects on the deformation characteristics both in consolidation settlement and lateral displacement. However, it can be aware that it is not dominants to the stress distribution in the aspect that the no changes in the residual excess pore water pressure. Therefore, the decision of the stiffness has to be carried out deliberately considering not only the consolidation the magnitude of the settlement and the lateral displacement, but the slope stability.

Study on the Ego states and Coping Style of Nursing Students (간호대학생의 자아상태와 대응양상과의 관계 연구)

  • Won, Jeong-Sook
    • Women's Health Nursing
    • /
    • v.8 no.4
    • /
    • pp.608-618
    • /
    • 2002
  • The purpose of this study is to analyze the type of ego states and stress coping style on female college students who are in the course of nursing study. This study is performed in the view of Transactional Analysis and designed to scrutinize descriptive correlations between the type of ego states and stress coping style. The subject is consists of 144 freshmen and sophomore, 138 junior and senior students group, who are students of K nursing college located in Seoul. The sampling investigation period is on Sept. 14, 2002 to Oct. 26, 2002. The measuring instrument used for Transactional Analysis ego state is 50 items Ego-gram research paper devised by Dusay(1997). For studying coping style, Folkman & Lazarus's measurement(1984) was adopted, which is translated and modified by Han, and Oh,(1990). Statistic average and standard deviation were generated by using SPSS PC+, t-test and Pearson correlation. The results were as follows: 1) In the type of ego states on both groups(lower group : freshmen, sophomore upper group : junior, senior) indicated the arithmetic apex NP(maximum value), then the point A was high and the data made a down slope to point AC. In the comparison to type of ego states between two groups, only at point CP, the data value of upper year students represented higher than that of lower year ones by C(t=2.28, p=.023). In the psychological energy level of ego states, both groups indicated average level.2) Stress coping style of whole students were highly and affirmatively dedicated to research. Consecutive consequences follow like this(high to low) : the central point of problem, search for social support, hopeful aspect and indifference. Especially hopeful aspect(t=.67, p=.05), relaxation of tension(t=-2.16, p=.03) made significant difference each other in the view of arithmetic calculation 3) While verifying coping style in terms of ego states level between lower and upper students group, In type CP, high level ego states group indicated significant difference on stress coping style area than low leveled group and made such sequences as the central point of problem, hopeful aspect, search for social support, positive interest and relaxation of tension. In type NP, sequences such as the central point of problem, search for social support, positive interest and relaxation of tension were emerged with little differences. In type A, the central point of problem, positive interest and relaxation of tension. In type FC, hopeful aspect, search for social support, positive interest and relaxation of tension. In type AC, hopeful aspect and indifference were derived significantly different(p<.05). 4) In the aspect of relation between ego states and coping style, type CP presented the central point of problem and relaxation of tension, type NP presented positive interest, search for social support and the central point of problem, type A showed the central point of problem, positive interest and relaxation of tension, type FC showed relaxation of tension, positive interest, search for social support, indifference and the central point of problem, type AC showed hopeful aspect, indifference and the central point of problem. All the sequence shown above had high-to-low procedure and represented static relations each other(p<.05).

  • PDF

Analysis of Landslide Hazard Area using RS/GIS (RS/GIS를 이용한 산사태 위험지역 분석)

  • Lee Yong-Jun;Park Geun-Ae;Kim Seong-Joon
    • Proceedings of the KSRS Conference
    • /
    • 2006.03a
    • /
    • pp.202-205
    • /
    • 2006
  • The objective of this study is to analyze the hazard-areas for landslide using GIS and RS. LRA (Logistic Regression Analysis) and AHP (Analytic Hierarchy Program) methods were used for evaluation of the hazard-areas by six topographic factors (slope, aspect, elevation, soil drain, soil depth, land use). These methods were applied to Anseong-si where frequent landslides were occurred mainly by the regional heavy rainfall. A landslide hazard-map of Anseong-si could describe into 7 hazard-grades. As results, LRA method was underestimated in higher grades areas, while AHP method was underestimated in lower grades areas. In order to evaluate the hazard-areas for landslides with accuracy, these results of each method were overlapped and the results of suggested method were compared with the historical landslide hazard records of KFRI (Korea Forest Research Institute).

  • PDF

Evaluation of Landslide Susceptibility Using GIS and RS (GIS 및 RS기법을 활용한 산사태 취약성 평가)

  • Kim, Kyung-Tae;Jung, Sung-Gwan;Park, Kyung-Hun;Oh, Jeong-Hak
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.8 no.1
    • /
    • pp.75-87
    • /
    • 2005
  • This study aims at predicting and mapping of the landslide susceptibility in the Geumho river watershed using GIS and Remote Sensing techniques. We constructed the spatial database of affecting factors such as slope angle, slope aspect, lithology, landuse, and vegetation index (NDVI) at a $30m{\times}30m$ resolution. The landslide susceptibility of the study area was predicted through overlay analysis and adding up estimation matrix, and the predicted map of landslide susceptibility with six categories (stable, very low, low, moderate, high, very high) was constructed. As the results, it showed that the very high susceptibility zones made up approximately 0.3% of the total study area, and these zones were mainly distributed in the forest area with the high slope angle and low vegetation index.

  • PDF