• Wind and Structures
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• v.4 no.2
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• pp.119-130
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• 2001

The paper addresses the suitability of wind pressure coefficients specified in contemporary design standards and codes of practice for gable roofs of intermediate slope (roof angle $10^{\circ}-30^{\circ}$). In a recent research study, a series of low building models with different roof slopes in this intermediate range were tested in a boundary layer wind tunnel under simulated open country terrain conditions. This was different from the original study in the 70's, which produced the current provisions on the basis of a model tested only for a single roof slope (4:12) in this range. The results of the study suggest that a modification to the American wind provisions would be warranted to make them more representative of the true local and area-averaged wind loads imposed on gable roofs of intermediate slope.

• Journal of applied mathematics & informatics
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• v.5 no.2
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• pp.489-498
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• 1998

The influence of observations the on the goodness-of-fit test in maximum likelihood factor analysis is investigated by using the local influence method. under an appropriate perturbation the test statistic forms a surface. One of main diagnostics is the maximum slope of the perturbed surface the other is the direction vector cor-responding to the curvature. These influence measures provide the information about jointly influence measures provide the information about jointly influential observations as well as individ-ually influential observations.

• Journal of the Korean Professional Engineers Association
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• v.19 no.1
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• pp.3-11
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• 1986

The analysis of Geotechnical stability problems by the limit equilibrium method involve assuming the shape of the failure and then investigating many surfaces of the shape to identify the one on which failure seems most likely to occur. These arbitrary assumptions most frequently concern to the locations or directions of side force on slice and the overall factor of safety is considered identical to the local factor of safety. In this paper, let the factor of safety of a slope at wedge block stage differently, when an upper part of the potential sliding mass has a simple active stress field and the lower part of the passive stress field and overall factor of safety is obtained by the average of local factor and computer program based on the modified wedge Method is proposed for this thesis. The new algorithm based on tile modified new method is made for estimating the safety factor of Earth Dam. Compared with conventional method for many cases tile average values of the factor of safety determined by the modified new method are very nearly the same. For all of the cases studied the difference was found 0.03. Finally this new method is thought to be very useful in slope stability analysis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.2
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• pp.79-85
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• 1989

The generation and propagation of shelf wave-like oscillations induced by local wind at a basin with continental shelf and slope are studied by a numerical experiment. Three types of vortices are generated along western boundary and they propagate along the boundaries in the counter-clockwise direction. The first vortex is generated at the early stage of wind stress and its center is located off the continental slope. The second type centered on the continetal slope is generated at about the terminating time of wind stress and follows the first one. The third, centered on continental shelf, decays so soon that its propagation pattern is hard to be identified. Each of those vortices is probably to be one of free modes of the model basin.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.2
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• pp.12-20
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• 2004

This study was carried out from January 1998 to December 1999 to report the revegetation of cutting-rock slopes and a design standard in the highway cut-slopes. The field data was collected from the 67 sites cutting-rock slopes of highways, local roads, and field test. As the result of analyze, cutting-rock slopes revegetation measures were 16 types. There were Vine planting(3 types), Hydroseeding measures with seed-fertilizer-soil materials(5 types), Vegetaion-base spraying measures(5 types), and Stability measures(3 types). The factors affecting the plant coverage rates of cutting-rock slopes were the slope gradient, the slope width and direction. The plant coverage rate decreases in the condition of steep slope and long slope width and length(height). In addition, the plant coverage rates of the westward and southward were lower than that of the northward and eastward. Most dominant species were Zoysia japonica, Lespedeza cyrtobotrya, Lespedeza cuneata, Rubus crataegifolius, Miscanthus sinensis, Arrundinella hirta, Themeda triandra, and Oenothera odorata. Exotic species were Eragrostis curvula(Weeping lovegrass), Dactylis glomerata Orchardgrass), Lolium perenne(Perennial ryegrass), and Festuca arundinacea(Tall fescue). It is recommended to adjust the proposed factor as environment, topsoil, classification of rock, field condition and characteristic related with revegetation measures on slopes for the presentation of revegetation standard.

• Journal of the Korean GEO-environmental Society
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• v.8 no.2
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• pp.19-27
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• 2007

In this study, the centrifugal tests were performed with varying the angle of slope such as 1:3, 1:2.5, and 1:2 in order to analyze the deformation and failure type of dredged clay slope for a short term. The displacement mode, displacement vector and the variation of pore pressure with the different slope angle were measured. As a results, even though the displacement in the slope after 4 months were developed in the case of 1:3 for the dredged slope, there are little problems to obtain the stability of dredged slope because the original construction section maintains. Also, in the case of 1:2.5 after 4 months the local slope failure occurred and in the case of 1:2 after 2 months the circle failure starting from the point of the tensile crack occurred. After reviewing the results, the maximum vertical displacement occurred at the crest of slope and maximum horizontal displacement was about double of maximum vertical displacement.

• Journal of the Korean GEO-environmental Society
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• v.19 no.9
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• pp.29-36
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• 2018

Several studies have been conducted on monitoring system and automatic measuring instruments to prevent slope failure in advance in Korea and overseas. However, these studies have quite complex structure. Since most of the measurement systems are installed on the slope surface, the researches are carried on the measurement system that detects sign of slope collapse in advance and alerts are still unsatisfactory. In this study, slope collapse experiments were carried out to understand the slope failure mechanism according to rainfall conditions. The water content and displacement behavior at the early stage of the slope failure were analyzed through the measurement of the ground displacement and water content. The results of this study can be used by local government as a basic data for the design of slope failure alarm system to evacuate residents in case of slope failure or landslide due to heavy rainfall.

• Tunnel and Underground Space
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• v.23 no.2
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• pp.99-109
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• 2013

The slopes of open-pit mine are typically designed without considering the reinforcement and support method due to the economical efficiency. However, the long-term stability of final pit slope is needed in some case, therefore the appropriate measures that can improve the stability are required. In this study, the field survey and laboratory test were carried out in S limestone mine. The stability assessment of final pit slope was performed through the stereographic projection method, SMR, and numerical analysis. And countermeasures for stabilization were proposed. The results of analysis show that full scale of slope failure is not expected but the failures of bench slope scale are likely to occur. In oder to increase the stability of bench slope, we suggested the remedial methods as follows: excavating the final pit slope by pre-splitting blasting, placing the wide berm in the intermediate bench slope and installing the horizontal drainage hole in the place of local ground water runoff.

• Journal of Ocean Engineering and Technology
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• v.24 no.1
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• pp.1-9
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• 2010

A series of experiments employing particle image velocimetry (PIV) technique was conducted to produce benchmark wave kinematics data for regular waves having four different wave slopes in 2-D wave tank. Water velocities and accelerations near the free surface of regular waves were computed from image pair obtained by PIV systems. With the measured wave velocity field, the wave accelerations were computed using a centered finite difference scheme. Both local and convective components of the total accelerations are obtained from experimental data. With increasing the wave slope, the horizontal velocity and the vertical accelerations near the wave crest obtained by PIV technique became larger than theoretical results, which are well-known phenomena of the wave nonlinearity. It is noted that the relative magnitude of convective acceleration to the local acceleration became larger with increasing wave slope.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.2
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• pp.69-78
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• 2010

The hydrological-geomorphic character is closely related with runoff in basin. A development of GIS greatly helps investigating about mechanism between theirs. We analyze local slope and hillslope length which are related with hydrological response. But variation of these geomorphic variables has very wide range at each pixel. So there's a limit as to use directly. Therefore we investigate a relation between hydrological response and distributed geomorphic variables according to statistical character of distributed map considering spatial correlation. As a result, the local slope affects peak discharge, and the hillslope length affects peak discharge and time, mean and variance of hydrological response. Henceforth these hydrological-geomorphic analyze methods can be improved that hydrology response is directly analogized with DEM data.