• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.1342-1348
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• 2010

Currently available evaluation checklists are developed for specific purposed using different parameters and items determined by different weighting factors. Those items with different weighting are sometimes said that they are based on the engineering judgement and leap of faith and, therefore, there is a limitation to adapt those checklists for slope-stability evaluation in the field. This study reviews factors affecting slope stability, analyze the relationship between those factors and slope failures using artificial neural network, and proposed a slope-stability evaluation model for adequate weighting for the factors.

• International Journal of Highway Engineering
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• v.10 no.1
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• pp.41-48
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• 2008

This paper deals with the characteristics of earth pressure to the debris-fall prevention walls which usually are installed in front of steep slope. Such walls have narrow backfill width where the active soil wedge can not be developed fully. The earth pressure to such walls ue affected by the movement of wall and arching effects due to the friction developing on the surface of adjacent ground slope and wall and therefore cannot be analyzed and calculated reliably. The study is carried out through laboratory model tests using centrifuge test. Test results reveal that the earth pressure to the debris-fall prevention wall depends largely on the inclination angle of the ground slope and the wall movement. The earth pressure reduction due to wall movement was observed at the upper half of wall, while the arching effect was significant at the lower half especially in the case of steep ground slope. It can be said that from the result of this study in the design of a debris-fall prevention wall the earth pressure should be determined considering the inclination of ground slope and the condition of wall movement during and after construction.

• Journal of Korea Water Resources Association
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• v.36 no.3 s.134
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• pp.455-464
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• 2003

In this paper, the experiments with installing a rainfall storage tank in the sub-surface were conducted and the reduction rates of the total runoff volume were investigated. The analysis were conducted based upon the variations of the rainfall intensity, surface coverage and surface slope. The reduction rate of the runoff volume was varied from 42.3% to 52.9% with the soil in the bank of the Seung Gi stream. In the experiments, the rainfall intensities were varied from 40mm/hr to 100mm/hr and the results indicate that the direct runoff reduction can be obtained with the installation of the rainfall storage tank in the sub-surface. The variation of the stored volume in the tank is very large in the mild slope but very small in the steep slope with over 3% slope. With this results, the reduction of the direct runoff volume for the longtime flood is expected with the installation of the rainfall storage tank in the region haying the steep slope such as the mountain area.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.2
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• pp.169-177
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• 2000

The modelling technique on the terrain of real-world in geo-spatial information system is a primary element for geo-information processing. This paper is designed to make use of TIN in geo-spatial information system and study the development and application of high-precision 3-D spatial analysis technique applied to terrain features. According to this research, MODEL 3 applied to breakline in mild slope/steep slope and MODEL 2 applied to peak in complex region show relatively low RMSE. This consequence proves that these two models have high precision in comparison with other models. This study also finds out optimal routines in the estimation method of slope grade and in the construction method of surface. N_T, LSP_T and LSQ_T in mild slope, N_T in steep slope, and LSQ_T in complex region turn out to be the optimal routines for high-precision 3-D spatial analysis.

• Korean Journal of Environmental Agriculture
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• v.37 no.3
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• pp.151-159
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• 2018

BACKGROUND: In this review paper, the effects of surface cover (SCV), vegetative filter strip (VFS), and vegetated ridge (VRD) on the pollutant runoff from steep-sloping uplands were analyzed to compare the pollutant reduction efficiency in runoff ($PRE_{runoff}$) of the practices and to investigate how slope and rainfall parameters affect the $PRE_{runoff}$. METHODS AND RESULTS: The $PRE_{runoff}$ of SCV, VFS, and VRD for pollutants including suspended solids and biological oxygen demand was compared by analysis of variance. The effect of slope and rainfall parameters on the $PRE_{runoff}$ was explored by either mean comparison or regression analysis. It was found that the $PRE_{runoff}$ differs with the practices due to different pollutant reduction mechanisms of the practices. Though the $PRE_{runoff}$ was likely to be affected by site condition such as slope and rainfall (amount and intensity), more comprehensive understanding was not possible due to the limited data set. CONCLUSION: The $PRE_{runoff}$ of SCV, VFS, and VRD differed due to the distinctive mechanisms of pollutant removal of the practices. It is necessary to accumulate experimental data across a variety of gradient of slope and rainfall for comprehensive understanding of the effects of the practices on pollutant runoff from steep-sloping uplands.

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.385-392
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• 2018

The slope stabilization analysis was performed by conducting survey and selecting the representative section in order to improve slope composition and management technology of masonry embankments in the quarry area, The mean slope of the masonry retain wall (A, B, C, D, E, F) was $38.5^{\circ}$, although the steep slope of the lowest slope (A) as $59^{\circ}$. The horizontal distance of the masonry embankments is 66.2 m and the slope height is 48.3 m. However, the inclination of the masonry embankments is relatively steep and visually unstable. The slope stability analysis for the slope stability analysis was taken into account during the drying and saturation. The slope stability analysis during saturation was performed by modeling the fully saturated slope. The strength constants of the ground were divided into two groups. The safety factor for dry period was 1.850 and the safety factor for rainy season was 1.333. The safety rate of dry period and rainy season was above 1.5 and 1.2. However, the weathered granite on the upper part of the masonry embankments at the time of heavy rainfall is considered to have a high risk of slope erosion and collapse. Therefore, it is considered necessary to take measures for stabilization through appropriate maintenance such as drainage installation.

• Proceedings of the Korea Contents Association Conference
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• 2015.05a
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• pp.5-6
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• 2015

A GNSS based measurement system was constructed with not only the core sensors of a GNSS receiver, a TRS sensor and a soil moisture sensor but supplementary installation of power supply and radio communication for monitoring steep slope sites. The sensor combination extracts and transfers not only ground displacement in real-time but soil moisture content.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.171-172
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• 2018

Dual gate L-shaped tunnel field-effect-transistor (DG-LTFET) is presented in this study. DG-LTFET achieves near vertical subthreshold slope (SS) and its ON current is also found to be higher then both conventional TFET and LTFET. This device could serve as a potential replacement for conventional complimentary metal-oxide-semiconductor (CMOS) technology.

• Water for future
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• v.28 no.6
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• pp.159-168
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• 1995

The run-up and the evolution of solitary waves on steep beaches are investigated by using a two-dimensional boundary integral equation model. The model is first used to compute the run-up heights of solitary waves on a relatively mind slope. The model is verified by comparing the computed numerical solutions with available experimental data, other numerical solutions and approximated analytical solutions. The agreement between the present numerical solutions and the other data is found to be excellent. The model is then applied to the calculation of run-up heights on very steep slopes. As far as the maximum run-up of solitary waves is concerned, the boundary integral equation model provides reasonable and reliable solutions. Finally, the evolution on steep beaches is also examined and the obtained wave heights are compared with those calculated from the Green's law.

• The Korean Journal of Petroleum Geology
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• v.2 no.2 s.3
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• pp.71-81
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• 1994

Alluvial fan delta often extends into deep water, forming steep-faced delta front. Depositional features of modern steep-faced fan-delta slope and prodelta are characterized by slump scar, chute/channel, swale, lobe, splay and debris fall. These features largely originate from sediment failure or sediment-laden underflows (sediment-gravity flows) off river mouth. Sedimentary facies of equivalent ancient systems comprise sheetlike and/or wedged bodies of gravelstone and sandstones, slump-scar and -fill, chute/channel-fills, and sheetlike, lobate and slump mass on steeply-inclined fan-delta foreset and prodelta.