• 제목/요약/키워드: Environmental Stability

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산림환경인자에 의한 임도 절토비탈면의 안정성 평가 (Stability Evaluation of Cut Slope in Forest Roads by Forest Environment Factors)

  • 전권석;오성윤;마호섭
    • 한국환경복원기술학회지
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    • 제6권4호
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    • pp.43-51
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    • 2003
  • 임도의 절토비탈면의 각 조사구를 토양침식 및 붕괴발생의 발생 유무에 따라 안정구와 불안정구로 구분하고 절토비탈면의 안정에 영향을 미치는 인자를 도출하여 비탈면의 안정성을 평가한 결과는 다음과 같다. 1. 절토비탈면에서 발생한 토양침식량은 표고, 상부(사면위치), 볼록사면(凸), 사면경사, 비탈면길이, 사질식양토(SiL), 남쪽(South)사면과는 정의 상관을, 식생피복도, 평형사면(${\square}$), 미사질식양토(SiCL)와는 부의 상관관계를 보였다. 2. 절토비탈면의 안정성 판별에 대한 상대적 기여도는 식생피복도, 토양경도, 사면경사, 표고, 미사질양토, 볼록사면, 복합사면의 순으로 나타났다. 3. 절토비탈면에서 안정구(2)와 불안정구(1)의 중심값은 각각 -1.194와 1.127로 나타났으며, 이때 판별구분치는 -0.072이었다. 4. 절토비탈면 조사구의 불안정구와 안정구에 대한 판별능력의 적중율은 불안정구는 125개 중 117개가 판별됨으로서 93.6%의 적중율을, 안정구는 117개의 조사구 중 102개를 판별 시켜 87.2%의 적중율을 보였으며 두 그룹의 전체 판별능력은 90.4%였다.

BTEX 분석용 토양 숙련도 표준시료(PTMs) 개발에 관한 연구 (A Study on the Development of Soil-based PTMs for Analysis of BTEX)

  • 이민효;이군택;이법열;이원석;김금희;홍석영
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제18권5호
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    • pp.15-25
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    • 2013
  • In this study, two kinds of soil-based proficiency testing materials (PTMs), NICE-012L and NICE-012R were prepared and certified for Benzen, Toluene, Etylbenzene and Xylene with evaluation of uncertainties. In order to analyse BTEX (Benzen Toluene Etylbenzene Xylene) for the candidate materials, GC/MS was used after pretreatment according to methods of soil analysis by Ministry of Environment. For the homogeneity test among bottles in terms of candidate materials, ISO 13528 and IUPAC Protocol were used and according to the result, both candidate materials showed sufficient homogeneity. Also, the stability test over the candidate materials was accessed according to the ISO Guide 35 by classifying short-term and long-term stability and the result showed that both candidate materials showed decent stability. The reference values of the two candidate materials depending on BTEX components were derived from the average of the 11 samples that were used for verification of the samples' homogeneity. Uncertainty of measurement was combined by uchar that was caused by a characteristic value, $u_{bb}$ that was caused by between-bottle homogeneity, and $u_{stab}$ that was caused by stability, and then combined uncertainty ($u_{PTM}$) was multiplied to the coverage factor (k) derived from the effective degree of freedom from each factor that leads to expanded uncertainty (U) in about 95% of confidence level. The proficiency testing materials developed through this study were supplied to National Institute of Environmental Research (NIER) and utilized as an external proficiency testing materials for evaluating analysis capacity of soil agencies with specialty in terms of soil analysis approved by Minister of Environment.

식재용 블록을 이용한 옹벽 녹화 기법에 관한 연구(I) - Eco-Stone의 시공 사례를 중심으로 - (The Retaining Wall Revegetation Technology Using Planting Blocks(I) - A Case study on the Eco-Stone structure -)

  • 한성식;정경진
    • 한국환경복원기술학회지
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    • 제2권1호
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    • pp.94-102
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    • 1999
  • The retaining wall is a structure which was made for changing land form in many construction. The first role of the retaining wall is to maintain the slope stability. But recently, the amount of retaining wall have been increasing because of the expansion of construction works and the amenity of urban environment have been decreasing because of environmental destruction and the scenic heterogeneity. So we should consider the slope stability and ecological stability at the same time. The purpose of this study is to develop the retaining wall revegetation technology using the Eco-Stone, the structure of co-satisfying which included the slope stability and the revegetation effect. Eco-Stone is a structure which has high stability for earth pressure, settlement and drainage. And cost and term of construction works also have been decreased. Eco-Stone structure is one of factors composing the ecological network which is harmonize with surrounding environment. In this way, it is expected that the ecological habitats of various species would be restored.

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GIS와 지구통계학을 이용한 충주호 남부지역의 광역적인 사면안정평가 (Regional Evaluation of Slope Stability by Using GIS and Geostatistics Around the Southern Area of Chungju Lake)

  • 문상기
    • 자원환경지질
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    • 제33권2호
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    • pp.117-128
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    • 2000
  • Regional evaluations of slope stability by the failure criterion and by environmental geological factors were conducted. The failure criterion is the general conditions for plane failure which consider the geometrical conditions between geological discontinuities and topographical slope planes. The factor focused in this condiction is dip and dip direction. Geostatics, named semivariogram was used for establishing structural domains in slope stability evaluation by the failure criterion. The influential range was calculated to 6 km in the case of dip direction of dominant joint set and 7 km in the case of dip of the same dominant joint set. Then applying this failure criterion to the study area produced a slope stability map using the established domains and slopes generated by TIN module of ARC/INFO GIS. This study considered another regional slope stability analysis. 5 failure-driven factors 9the unstable slope map, geology, engineering soil, groundwater, and lineament density) were selected and used as data coverages for regional slope stability evaluation by geoenvironmental factors. These factors were weighted and overlayed in GIS. From the graph of cumulatave area (%) and instability index, finding critical points classified the instability indices. The most unstable slopes are located in the southern area of Mt. Eorae, Dabul-ri, and the eastern area of Junkok-ri in the first area is plane failure. Also, the expected orientations of failure are 59/338 and 86/090 (dip/dip direction).

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원격탐사와 지구정보시스템을 이용한 충주지역의 사면안정분석 (Analysis of Slope Stability by Using Remote Sensing and GIS Around Chungju Area)

  • 신현준;이영훈;민경덕;원중선;김윤종
    • 자원환경지질
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    • 제29권5호
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    • pp.615-622
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    • 1996
  • Slope stability analysis was conducted using remote sensing and Geoscientific Information System (GIS) as a part of natural hazard assessment around Chungju area. Landsat TM band 5 and 7 which contain more information about geological structure and geography are chosen and processed to analyse regional geological structure. Through image processing technique such as PCA, HFF, edge detection and enhancement, regional lineament can be mapped and identified. The lineament density map is constructed based on summed length of lineaments per unit area and the study area can be divided into 7 structural domains. Various factors of slope stability analysis such as geology, slope aspect, degree of slope, landcover, water shed as well as characterized structural domain are constructed as a database of GIS. Rating and weighting of each factor for slope stability analysis is decided by considering environmental geological characteristics of study area. Spatial analysis of regional slope stability is examined through overlaying technique of the GIS. The result of areal distribution of slope stability shows that the most unstable area is all over Jaeogae-ni, Hyangsan-ni and Mt. Daedun.

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확률신경망을 이용한 방파제 피복재 설계 (Estimation of the Stability Number of Breakwater Armor Blocks Using Probabilistic Neural Networks)

  • 김두기;김동현;장성규;장상길
    • 한국해양공학회지
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    • 제20권5호
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    • pp.70-76
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    • 2006
  • A Probabilistic neural network (PNN) technique for predicting the stability number for the armor blocks of breakwaters is presented. A PNN is prepared using the experimental data of van der Meer and is then compared with the empirical formula and previous artificial neural network (ANN) model. This comparison shows that a PNN can effectively predict the stability numbers in spite of data complexity, incompleteness, and incoherence, and can be an effective tool for the designers of rubble mound breakwaters to support their decision process and to improve design efficiency.

절리 간격이 암반 사면의 안정성에 미치는 영향 (Influence of Joint Spacing to Rock Slope Stability)

  • 윤운상;권혁신;김정환
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 가을 학술발표회 논문집
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    • pp.511-518
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    • 2000
  • Characteristics of joint orientation, length, spacing and their distribution are very important factors for slope stability, Especially, the effect of joint spacing is an essential factor of slope stability. This study is to analyze the effect of joint spacing in cases of sliding and toppling, which is a typical failure mode. Joint spacing can divided into vertical spacing(spacing) and horizontal spacing(gap). And then, the spacing/length ratio of joint directly affect rock slope failure. When the ratio is below 0.05, the possibility of failure is rapidly increased. In case of toppling, the possibility of failure depends on the ratio of spacing to height of slope ratio slope. As the ratio decreases, the possibility of toppling failure increased. The critical ratio of spacing to height of slope is determined by the dip angle of the slope and the orientation of joint sets.

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Pasquill 安定度階級의 評價와 安定度 Parameter 測定方法의 開發 (Evaluation of Pasquill Stability Class with Monin-Obukhov Length and Estimation Scheme of Stability Parameter)

  • 이종범;김용국
    • 한국대기환경학회지
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    • 제6권2호
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    • pp.168-175
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    • 1990
  • Pasquill stability class (PSC) was evaluated with Monin-Obukhov length (L) using the data observed at a height of 213m meteorological tower in Tsukuba, Japan. PSC was determined with wind speed and insolation (net radiation at night), and L was calculated with the heat flux and the friction velocity obtained at 25m by the eddy correlation method. To evaluate PSC with L, for every class of Pasquill stability (from A to F class), percentiles and median of L were used. Results show that for every class of Pasquill stability, L varies so widely that PSC does not adequately represent the atmospheric stability conditions. The scheme which estimates L using air temperature at two levels and wind speed at single level was developed. Comparison between estimated L by the scheme and observed L reveals that the scheme is better than PSC. Furthermore, the scheme is more advantageous than PSC because it uses air temperature at two levels instead of insolation which is more difficult to observe in the field than air temperature.

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