• Journal of Korean Physical Therapy Science
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• v.19 no.1
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• pp.63-69
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• 2012

Background : The purpose of this study was to investigate the frequency domain characteristics of ground reaction forces during quiet standing on inclined surfaces twenty healthy individuals(10 elderly women $68.78{\pm}3.29$ years and 10 young women $20.90{\pm}0.74$ years) participated. Methods : Subjects stood in quiet stance over a force platform positioned in one of three different fixed positions: flat, down and up. Healthy participants completed with eyes open for 120 s trials. Evaluation of postural control were generally based on the interpretation of center of pressure(COP) time series. The COP have been determined using an experimental setup with 3D kinematic and the ground reaction force system. All the data were expressed means and standard deviation by using SAS package program. Results : SEF 50% were not significant in AP and ML direction according to surface slope of both groups. SEF 95% were showed highest frequency in AP direction on down slope of both groups. MEF were not significant all direction according to surface slopes of elderly women. There was no difference between young and elderly women. Conclusion : Elderly women used to ankle strategy during a quiet stance according to COP perturbation of AP direction showed more expanded than ML direction. SEF 95% were showed highest frequency on down slope in elderly women who showed more used ankle strategy for postural control on down slope.

• Magazine of the Korean Society of Agricultural Engineers
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• v.11 no.3
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• pp.1719-1723
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• 1969

In this country, farmers lay out furrows in the direction which is considered by their own judgement to be convenient for cultivation without paying much attention for soil erosion. The direction of furrow has considerable effects on soil and water losses. In this experiment, it is intedned to observe the differences of soil and water losses in different directions of furrows of sloped fields so that the results thus obtained could be informed to farmers who should be careful in determining furrow direction for soil erosion control. Some the major experimental results are summarized as follows: The direction of furrows did not affect so much on the runoffs in a gentle slope, as the runoff is 509 ton/10a in the contouring plot, $51^{\circ}$/ton/10a in the 45-degree plot, and 560 ton/10a in the up-and-down hill plot. The contouring plot among the three plots had best effect on soil conservation, as the soil losses are 5.8 ton/10a in the contouring plot, 9.3 ton/10a in the 45 degree plot, and 10.2 ton/10a in the up-and-down hill plot.

• Ocean and Polar Research
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• v.42 no.1
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• pp.49-61
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• 2020

We analyzed the morphological characteristics of OCC (Ocean Core Complexes) in the middle part of the Central Indian Ridge (MCIR) using high-resolution geophysical data recorded on the Deep-Tow SideScan Sonar IMI-30 system. In terms of slope-gradient variations calculated from the high-resolution bathymetry data, the normal faults formed by seafloor spreading were associated generally with slopes > 30° and resulted in high backscatter intensities, which reflect more topographic effects than acoustic medium variation. However, the areas associated with gentle slopes < 10° tend to show the backscatter intensities reflecting the acoustic characteristic of the medium. We show that the detachment faults exposing the OCCs were initiated with high-angle normal faults (58°) exhibiting outward and inward dips of a breakaway zone. In order to examine the spatial distribution of OCC structures, we characterized the transition from magmatic-dominant seafloor with abyssal hills to tectonic-dominant seafloor with OCC using the down-slope direction variation. The slope direction of the seafloor generally tends to be perpendicular to the ridge azimuth in the magmatic-dominant zone, whereas it becomes parallel to the given ridge azimuth near the OCC structures. Therefore, this spatial change of seafloor slope directions indicates that the formation of OCC structures is causally associated with the tectonic-dominant spreading rather than magmatic extension. These results also suggest that the topographical characteristics of seafloor spreading and OCC structures can be distinguished using high-resolution geophysical data. Thus, we propose that the high-resolution bathymetry and backscatter intensity data can help select potential areas of exploitation of hydrothermal deposits in MCIR effectively.

• Journal of Korean Tunnelling and Underground Space Association
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• v.15 no.4
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• pp.387-400
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• 2013

In this study, the slope stability analysis and the landslide hazard assessment in tunnel portal slope were carried out. First, we selected highly vulnerable areas to slope failure using the slope stability analysis and analyzed the slope failure scale. According to analyses results, high vulnerable area to slope failure is located at 485~495 m above sea level. The slope is stable in a dry condition, while it becomes unstable in rainfall condition. The analysis results of slope failure scale show that the depth of slope failure is maximum 2.1 m and the length of slope failure is 18.6 m toward the dip direction of slope. Second, we developed a 3-D simulation program to analyze characteristics of runout behavior of debris flow. The developed program was applied to highly vulnerable areas to slope failure. The result of 3-D simulation shows that debris flow moves toward the central part of the valley with the movement direction of landslide from the upper part to the lower part of the slope. 3-D simulation shows that debris flow moves down to the bottom of mountain slope with a speed of 7.74 m/s and may make damage to the tunnel portal directly after 10 seconds from slope failure.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.6
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• pp.629-635
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• 2009

In this research, KP-4, one of the plastic mold steels, was coated with the AlTiN from one layer to four layers by the PVD method in the $\Phi$ 8mm cemented carbide ball end mill. Coated KP-4 was processed with various conditions. For example, slope of $15^{\circ}$, $30^{\circ}$ and $45^{\circ}$ the spindle rotation speed was changed from 10,000rpm to 16,000rpm, the tool feeding speed was changed from 1,300mm/min to 1,700mm/min, the depth of cut was also changed from 0.3mm to 0.9mm, and etc. Cutting component force according to the coating layer number, and surface roughness were studied. The cutting component force showed a good agreement better the up ward direction than the down ward direction under all experimental conditions. In case of the condition per the material shape, it was lessen when the tool have larger angle because the average effective diameter of the tool is larger. The surface roughness showed good condition in case of the up ward than the down ward direction. And, in the 3rd layer of AlTiN coating, it showed the most suitable condition.

• Journal of the Korean Institute of Rural Architecture
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• v.8 no.1
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• pp.111-120
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• 2006

Our ancestor has accumulated inimitable a building system from experience. and they finally invented Gu-dul that heat the stone as a hitting system. The purpose of this study is to investigate and to write down the on Excavation & Restoration of Traditional Gu-dul in Young-dong. It was found that Gu-dul was the most suited for natural condition. That is wind, direction, earth level. As the results of analyzing the built- technque of traditional Gu- dul : 1) The Gu-dul type is lined, scattered, and mixed. 2) The hight of bank is 25-30cm, 3) The depth of Gaejari is 30-45cm, and The slope of that is gentle. 4) The slope of Gorae(a floor hitter) is 5 - 8%. (from the middle to the edge and from the lower part to the upper part) Therefore, For the practical application of future houses, it will be needed to develop the reasonable hitting system, and suggest to set up Gu-dul for our health and saving energy.

• Atmosphere
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• v.25 no.4
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• pp.591-600
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• 2015

We have analyzed wind and eddy covariance data collected within roughness sublayer over sloping terrain. The study site is located on non-flat terrain with slopes in both south-north and east-west directions. The surface elevation change is smaller than the height of roughness element such as building and tree. This study examines the directional wind shear for data collected at three levels in the lowest 10 m in the roughness sublayer. The wind direction shear is caused by drag of roughness element and terrain-induced motions at this site. Small directional shear occurs when wind speed at 10 m is strong and wind direction at 10 m is southerly which is the same direction as upslope flow near surface at this site during daytime. Correlation between vertical shear of lateral momentum and lateral momentum flux is smaller over steeply sloped surface compared to mildly sloped surface and lateral momentum flux is not down-gradient over steeply sloped surface. Quadrant analysis shows that the relative contribution of four quadrants to momentum flux depends on both surface slope and wind direction shear.

• Journal of Biomedical Engineering Research
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• v.28 no.2
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• pp.187-194
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• 2007

The purpose of this study is to determine the characteristics of ground reaction force(GRF) in golf swing for various slopes of flat lie and uphill lies of 5 and 10 degrees. Five right-handed professional golfers were selected for the experiment and the 7 iron club was used. We used four forceplates to measure GRF and synchronized with the three-dimensional motion analysis system. Results showed that slope did not affect the total time for golf swing, but the time until the impact had a tendency to slightly increase for the uphill lie(p<0.05). The medial-lateral GRF of the right foot increased toward the medial direction during back swing, but less increases were found with the angle of uphill lie(p<0.05). The GRF of the left foot increased rapidly toward the medial direction at the uncocking and the impact during down swing, but decreased with the increase in the angle of uphill lie(p<0.05). The anterior-posterior GRF of both feet showed almost the same for different slopes. With the slopes, the vertical GRF of the right foot increased, but the vertical GRF of left foot decreased(p<0.05). Uphill lies would have negative effect to provide the angular momentum during back swing, restricting pelvic and trunk rotations, and to provide the precise timing and strong power during down swing, limiting movements of body's center of mass. The present study could provide valuable information to quantitatively analyze the dynamics of golf swing. Further study would be required to understand detailed mechanism in golf swing under different conditions.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.256-263
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• 2013

The field lysimeter study was undertaken to investigate influence of agricultural practice and topography on runoff and erosion loss of fluazinam from the sloped land grown pepper. The WP type formulation was applied on July in 2003~2005. The wash-off rates were from 1.4% to 8.4% of the applied fluazinam. The runoff losses of fluazinam from a series of pepper grown-lysimeter plots were 0.14~0.90% in the first year, 0.01~0.04% in the second year and 0.16~0.37% in the third year for the mulched contour ridge plots, 0.47~1.59% for the mulched up-down direction ridge plots and 0.07~1.05% for the no-mulched contour ridge plots as the control, and they increased with slope degree. Concentrations of fluazinam in runoff water ranged mostly to 10 ${\mu}gL^{-1}$ at the first runoff event. Erosion rates from plots except the mulched up-down direction ridge plots was 0.00~0.21% for 10% and 20% slope-plots and 0.15~1.05% for 30% slope-plots with different slope degrees. Erosion rates from the mulched up-down direction ridge plots were 0.47~1.59% for 10% slope-plots and 0.75~1.05% for 20% slope-plots. Residues of fluazinam in soil at ten days after the application ranged from 0.007 mg $kg^{-1}$ to 0.059 mg $kg^{-1}$ except the soil under the mulch. After then the fluazinam residue in soil was dissipated at the rate of 20 days of half-life to below 0.01 mg $kg^{-1}$ at 60 days after the application.

• Journal of the Korean Geotechnical Society
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• v.35 no.5
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• pp.21-30
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• 2019

While the study of the shallow tunnel has been mainly on the longitudinal load transfer and horizontal surface conditions, the study of the ground behavior of shallow tunnel under the slope is not sufficient. Therefore, in this study on the ground behavior around a tunnel due to the sidewall deformation of shallow tunnel under the slope that is excavated in longitudinal direction, a scale-down model test has been performed. The model tunnel has the dimension of 320 mm wide, 210 mm high and 55 mm long with enough material strength in aluminum and the model ground has the uniform ground conditions by 3 types of carbon rods. The model test has been performed with the variables of slopes and the cover depths by controlling the tunnel sidewall deformation, and the change of sidewall-load, load transfer, ground subsidence was monitored and analyzed. According to the increase of the slope, the maximum ground subsidence increased by 20~39% compared to the horizontal surface. The load ratio increased by maximum 20% in the tunnel crown and decreased in sidewall according to the surface slope. The load transfer shows maximum 128% of increase at the cover depth of 1.0D, while at the 1.5D cover depth it shows non-critical difference from horizontal surface. The slope has major effects on load transfer at the cover depth of 1.0D.