• Journal of the Korean Geosynthetics Society
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• v.11 no.4
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• pp.63-69
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• 2012

Climate change, according to the country to increase locality of slope collapse of heavy disaster, such as increasing the likelihood and prior in order to prevent these disasters, "Slope construction design standards (Ministry of Land, 2011)," is prescribed in the relevant guidelines. In recent years, guidelines Slope Stability Analysis of the existing methods when the rainy season infiltration of rainfall, taking into account have been revised to perform more realistic. In this study, according these trends to the analysis of saturation depth by rainfall intensity and soil conditions. Results as a whole, the larger the saturated hydraulic conductivity and depth of rainfall intensity also showed a tendency to rise in proportion but MH, CL did not occur in the saturation region. Analysis of antecedent rainfall case also reflects an overall increase of depth in the saturated, rainfall in many cases is less than the growth rate was higher in the saturation region.

• Journal of the Korean Geotechnical Society
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• v.30 no.4
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• pp.81-92
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• 2014

The integrity evaluation of river levee includes slope stability evaluation of riverside land and protected low-land, and safety of piping with respect to critical gradient and critical velocity based on related regulations, such as Design Criteria Rivers Commentary (2009), Structural Design Criteria Based Commentary (2009). The design hydro-graph is the most important design input factor for the integrity evaluation; it can be inaccurate due to the absence of its decision methods suggested by the national level. The authors in this paper evaluated numerical analytic levee integrity for piping and slope stability by changing each design hydro-graph, including rising ordinary water level, lasting flood water level, falling water level, and flood frequency for Mun-san-jae on Nak-dong River. Finally, the authors suggested that the levee integrity of piping and slope stability are very sensitive to the changes of increasing time of ordinary water level by 57 hours and lasting time of the flood water level by 53 hours, respectively, for Mun-san-jae.

• Economic and Environmental Geology
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• v.6 no.1
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• pp.29-64
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• 1973

A land resources survey in the semi-arid area, Mula in S. E. Spain, of $400km^2$ is compiled. The basic aim of the project is to investigate the intrinsic qualities of the land resources of the area by means of applying an integrated method of natural resources survey mainly concerning with analysis and synthesis of land complexes, each of them represents an area or a group of areas with similar patterns of landforms, soils and vegetation, based on a geomorphological approach. The area is characterized by a linear arrangement of relief pattern with an asymmetric homoclinal repetition of slope attitudes elongating WSW-ENE, dipping steeply on the NW sides and gently on the SE sides, which have been resulted from the post-Alpine folding of the Triassic to Cretaceous limestone, the Eocene limestone, the Oligocene sandstone and the lower Miocene limestone and marl, and the post-lower Miocene faulting, tilting and subsequent differential erosion of the Miocene sedimentary formations. An integrated body of information in geology, landforms, soils and vegetation, which are significantry interrelated as an environmental complex, has been obtained. Using this data, 26 land complexes developing on the various situations of landforms, such as folded mountain ranges, tilted tablelands, bevelled cuestas, degraded hill-lands associating with enormous foots lopes, undulating terrains and terraced or flat plains, have been differentiated, mapped and described. The soils of the area are mostly light colored calcic lithosols which have been derived dominantly from the marly parent materials and developed into remarkable slope catenas in some places depending on the relief conditions. The land uses of the area are mainly characterized by the perennially irrigated cultivation of citrus orchards along the terraced alluvial deposits fringing the Segura and Mula River, and the dry-land cereal cultivation on gentler slopes. Pioneer dry-land cultivations within the shrubs on steeper slopes are restricted to the unchannelled tributary drainage floors. The availability of water is a fundamental controlling factor for existence of native and cultivated vegetation as a whole, and a number of active processes including sheet wash and gully erosion, especially on the scarp slopes, are the other important factors to be considered in conservation and management of the land in the area.

• Journal of the Korean Society of Safety
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• v.31 no.2
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• pp.49-56
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• 2016

In Korea, there exist many mountains, and sudden storms occur during the summer season. When severe rainstorm events occur in steep slope topography, risk of debris flow is increased. Once debris flow occurs in urban area, it may cause casualties and physical damages due to rapid debris flow velocity along a steep slope. Accordingly, preventing method of sediment-related disaster for demage mitigation are essential. Recently, various studies on debris flow have been conducted. However, the prediction of the physical propagation of debris flow along the steep slope was not thoroughly investigated. Debris flow is characterized by various factors such as topography, properties of debris flow, amount of debris flow. In the study the numerical simulation was focused on the topographic factor. Fundamental analysis of the risk area was implemented with emphasis on the propagation length, thickness, and the development of maximum velocity. The proposed results and the methodology of estimating the structural vulnerability would be helpful in predicting the behavior and the risk assessment of debris flow in urban area. These results will be able to estimate the vulnerability of urban areas affected the most damage by debris flow.

• Journal of Korean Society of Forest Science
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• v.94 no.3 s.160
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• pp.129-134
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• 2005

Ths study was carried out to understand the geo-topographical characteristics of the landslide area (1.5 ha) in Maeri, Sangdong-myeon, Gimhaesi, Gyeongsangnam-do. The bedrock of the landslide area was diollites and the area in and around the upper slope with the scattered talus was composed of Masanam originated from Igneous rocks. The landslide occurred in 19th of April, 2004 and the amount of rainfall for 3 days before the landslide was 74mm. The landslide by land creeping in this area was mainly attributed to geo-topographical characteristics such as well developed colluvial and/or weathered soils, and land cutting in lower slope, although the landslide could be affected by the rainfall. The type of the landslide can be classified into the land creeping by concave colluvial soils.

• Journal of Environmental Science International
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• v.19 no.5
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• pp.543-548
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• 2010

This research was made to investigate the effects of burned, which is made in the early spring every year at Saebyeol-Oreum from 2003 to 2009, on changes in vegetation on the grassland. The results of analyzing the characteristics of the lay of the land showed that the proportion of the surface land that had the angle of azimuth and the angle of slope in the range of southeast $135^{\circ}{\sim}180^{\circ}$ accounting for 73.89% and $21^{\circ}{\sim}30^{\circ}$ accounting 58.33% of the entire surface land, respectively, was found to be highest. The results of the analysis showed that the relative importance value was found to be lowered from 27.07 in 2003 to 19.47 in 2009, and this can be attributable to the relative importance value of Artemisia japonica having been heightened from 7.07 in 2003 to 16.23 in 2009. The reason that the relative importance value of Artemisia japonica was found to be high is thought to be that vegetation on the surface land was removed by burned in the early spring and, due to this, the dry surface of soil and the high slope accelerated the soil erosion and could not provide proper environment of the growth and development for Imperata cylindrical and Miscanthus sinensis, so Imperata cylindrical and Miscanthus sinensis were excluded and Artemisia japonica whose importance value had been highest have flourished. Researches to maintain the current vegetation on the burned location of Saebyeol-Oreum and to adjust physical characteristics of soil to restore vegetation and the proper time and cycle of burned should be conducted.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.1
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• pp.55-60
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• 1998

This study was conducted to investigate the effects of the pasture types and the leveling methods of winding slope land for seedbed on the runoff, soil loss, botanical composition, dry matter yield of forage and economical value at the Experimental Field of Grassland and Forage Crops Division, National Livestock Research Institute, Suweon, from 1994 to 1995. The results obtained are summarized as follows: 1. Runoff of the improved land was higher than that of the unimproved land in the top grass and bottom grass. 2. Soil loss of the improved land was higher than that of the unimproved land in the top and bottom grasses in the first year. However, it was slightly higher in the unimproved land, and all of it were greatly decreased in the second year. 3. The percentage of grasses coverage was increased with the improved land in the first year, and it was not different between the improved land and unimproved land in the second year. Also, it was slightly increased in the bottom grasses. 4. Dry matter yield of grasses was increased with improved land at the top and bottom grasses. DM yield of grasses was increased in the top grasses in the first year and bottom grasses in the second year, respectively. 5. The establishment cost of grasses was decreased with wages decrement, and the management cost was saved about 1,116,000 won per ha with improved land. The results demonstrated that although soil loss was increased by leveling methods of improved land irrespective of pasture types in the first year, it was decreased with time little by little. Also, improved land was very good for grasses coverage, dry matter(DM) yield and economical value.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.4
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• pp.1-15
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• 2023

This research intended to reveal the special characteristics of the vegetation structure and the tendency of change of -landfill slope districts, which are reclaimed land, through an investigationsinto the presently existent vegetation and plant community structure of the World Cup Park landfill slope district. For the analysis of changes in vegetation, this study compared the results of field surveys in 1999, 2003, 2005, 2007, 2008, 2012, 2016, and 2021. For the investigation into the plant community structure, a field investigation was carried out in 2021 with six fixed investigation districts designated in 1999 as subjects. To analyze the change in the plant community structure, the past data on the population, the number of the species, and the species diversity by the layer in 2021 were compared and analyzed in the landfill slope district, which is reclaimed land. The changes of the vegetation distribution and the power had been affected by typhoons (Kompasu). Above the plantation foundation, which had been dry and poor, Salix koreensis, marsh woody plants that had formed the community, decreased greatly. The Robinia pseudoacacia community, after the typhoon in 2010, decreased in the number of species and population. Afterward, it showed a tendency to rebound. Regarding the Ailanthus altissima-Robinia pseudoacacia-Paulownia tomentosa community, the number of the species and the population had shown a change similar to the Robinia pseudoacacia community. The Paulownia tomentosa and the Ailanthus altissima have been culled. The slope was predicted as a Future Robinia pseudoacacia forest. The Salix pseudolasiogyne community has been transitioning to a Robinia pseudoacacia forest. Only some enumeration districts, the Robinia pseudoacacia forests and the Salix pseudolasiogyne, had been growing. However, most had been in been declining. It was predicted that this community will be maintained as a Robinia pseudoacacia forest in the future. As these vegetation communities are the representative vegetation of the landfill slope districts, which is reclaimed land, there is a need to understand the ecosystem changes of the community through continuous monitoring. The results of this research can be utilized as a basic material for the vegetation restoration of reclaimed land.

• Journal of the Korean Society of Safety
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• v.26 no.2
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• pp.83-88
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• 2011

Annually, many parts of the Korea have been damaged from the localized heavy rain and/or typhoons which peak between June and September, which result in extensive financial and human loss. Especially, because the most area of Gangwon province is composed of the steep slope mountains, the damages by the debris flow or land-sliding are more frequent and the frequency has been increased. To analyze the characteristics and causes of these debris flow disasters, lots of study are recently being conducted through database of weather, hydrologic, soil etc using a GIS or remote sensing. In this study, we applied GIS method to analyze the risk of the debris flow area. With the statistical analysis and infinite slope stability model(SINMAP), the debris flow risk level of the mountain slope was generated. As a result, the GIS statistical analysis showed high correlation that former model of SINMAP in determining the debris flow risk area.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.535-542
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• 2001

The objective of this study is to develop a spatial analysis modeling technique to evaluate the functional suitability of forest lands for land slide prevention. The functional suitability is classified into 3 categories of high, medium and low according to the potential of land slide on forest lands. The potential of land slide hazards is estimated using the measurements of 7 major site factors : slope, bed rock, soil depth, shape of slope, forest type and D.B.H. class of trees. The analytic hierarchical process is applied to determining the relative weight of site factors in estimating the potential of land slides. The spatial analysis modeling starts building base layers for the 7 major site factors by $25m{\times}25m$ grid analysis or TIN analysis, reclassifies them and produces new layers containing standardized attribute values, needed in estimating land slide potential. To these attributes, applied is the weight for the corresponding site factor to build the suitability classification map by map algebra analysis. Then, finally, cell-grouping operations convert the suitability classification map to the land unit function map. The whole procedures of the spatial analysis modeling are presented in this paper.