• Proceedings of the Korean Geotechical Society Conference
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• 2003.06a
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• pp.33-42
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• 2003

Since the cut slope has been big concern due to frequent failures, the government decided to include cut slopes in the“Act for Safety Control of Public Structures”. Based on the Act, the cut slope whose height is over 50m and length is over 200m should be inspected on the regular basis. According to the Act, KISTEC developed the objective evaluation method for the condition of cut slope. The evaluation method is divided into two categories: evaluation for damaged condition and evaluation for failure affecting factor. Based on the evaluation results, the cut slope is graded from A to E. In this study, the process to evaluate the cut slope condition and the evaluation criteria to divide the grade of cut slope are introduced.

• Journal of Industrial Technology
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• v.21 no.B
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• pp.51-58
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• 2001

The Distinct Element Method (DEM) was used to analyze the stability of jointed rock slope, of which dimension are about 200m(length), 60m(height), $55^{\circ}$ dip. The Barton-Bandis joint model was used, as a constitutive model. The parameters such as JRC and spatial distribution characteristics of discontinuities were acquired through field investigation. Three different cases such as $51^{\circ}$, $45^{\circ}$ and $38^{\circ}$ in angle of rock slope were analyzed to decide a stable slope. To keep the jointed rock slope safely, it is proposed to reduce the height of slope from 60m to 48m and to reduce the angle of the from $55^{\circ}$ to $38^{\circ}$ too.

• Korean Journal of Applied Biomechanics
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• v.24 no.3
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• pp.259-267
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• 2014

The purpose of this study was to find the relationship between standing posture biomechanics and physical fitness in the elderly. Physical fitness variables and postural variables for 227 (140 women and 87 men) elderly individuals were tested. Physical fitness tests (Korean Institute of Sports Science, 2012) included 3m sit, walk, and return, grip test, 30 second chair sit and stand, sit and reach, figure 8 walks, and 2 minute stationary march. Postural biomechanics variables included resting calcaneal stance position (RCSP), shoulder slope, pelvic slope, knee flexion angle, leg length difference, thoracic angle, and upper body slope. In statistical analysis, multiple regression was conducted by using stepwise selection method via SAS (version 9.2). Analysis for both men and women revealed significant relationships between physical fitness and age, upper body slope, knee flexion angle, leg length difference. Pelvic and thoracic angle were only related to figure 8 walking and sit and reach in women, while RCSP and shoulder slope had no relationship with any physical fitness variables.

• Journal of the Korean GEO-environmental Society
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• v.16 no.3
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• pp.41-48
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• 2015

Several sensor systems are used to estimate and predict the slope behaviors, however though slope sensing systems are much up-to-dated compared to before, they are mainly focused on the hardware developing. It means the analyzing software is deficient to apply the examining slope behavior for slope stability. In real case, slope behavior shows the 3-dimensional movement and failure; however the modeling methods for 3-D behavior are more difficult and need more variables. 1-D analysis shows only the length variation, however the real slope makes the 3-D behaviors. To fix the 3-D space coordinate, three values should be determined such as length, horizontal angle and vertical angle. Therefore if the 3-D coordinate system were composed by the points considered of two directions and length, the 3-D space could be separated into horizontal plane and vertical plane. The data from DY-slope in Chungbuk province was analyzed to the developed 3-D coordinate system. It is concluded from the results of 3-D analysis, the slope is generally moving to transverse direction, also the displacements are happening to road and vertical direction at the same time. Presently, the accumulated displacement between sensing points shows small value within 4.3 cm, and the displacements of all sensing points show the similar directions and magnitudes.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.1
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• pp.1-9
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• 2000

The purpose of this study was to analyze the characteristics of soil erosion on the fill-slope of forest road by elapsed years after road construction. Thirteen plots were established on the fill-slope of the newly-constructed forest road, and surveyed for two years(1997~1998). In these plots, the data about soil erosion, surface runoff, vegetation coverage, slope structural characteristics and rainfall were collected. In 1997, the major causes for soil erosion were found by the correlation coefficients with the amount of surface runoff from the fill-slope, vegetation coverage, slope length, slope degree, total rainfall and max. 1 hour rainfall. But, in 1998, the major causes for soil erosion were vegetation coverage and slope degree. Using the stepwise multiple regression method, in 1997, the amount of soil erosion from the fill-slope was complexly expressed as a exponential function of statistically significant the amount of surface runoff from the fill-slope, total rainfall, slope degree of fill-slope and vegetation coverage, but, in 1998, simply expressed as a exponential function of vegetation coverage.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.1
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• pp.61-64
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• 1994

The NMOSFET with gate length of 0.1$\mu$m is fabricated by mix-and-match method. In this device, the electron beam lithography is used to form the gate layer, while other layers are formed by the stepper. The gate oxide is 7nm thick, and the device structure is normal LDD structure. The saturation Gm for gate length of 0.1$\mu$m is 246mS/mm. The subthreshold slope is 180mV/decade for 0.1$\mu$m gate length, but the slope is 80mV/decade for 0.3$\mu$m gate length.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.722-726
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• 2010

Inventory survey is process collecting data about cut slope. It's different from inspection. It contains not only basic information about cut slope, especially location, GPS positioning, height, length, weathering, joint direction, water conditions but also level of danger and damage. Collected data are being used get at status about cut slope along national roads. And It helps judging about priority of detailed investigation. According to results of analysis, we found better method about maintenance of cut slope. Later on, if inventory research is finished, we will understand characteristics of collapse slopes.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.4
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• pp.41-52
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• 2013

This study was carried out in order to analyze the succession characteristics of the slope of expressways and the results of analysis by collecting and analyzing various literatures and data from 2011 to 2012 and surveying 75 expressway slope, as follows : The construction methods applied to planting the slope of an expressway can be classified into 4 types including 3 Climber planting methods, 8 Vegetation thick-layer spray work methods, 4 Seed spray work methods, and 4 Stabilization work methods. The factors which affect the cover degree of the slope of an expressway were found to be development years, gradient, length, and azimuth. Like surrounding forest areas, the expressway slope was analyzed to begin the plant succession 20, 30, and 40 years after development, and plant succession was developed in diversity in a mixed stand forest according to surrounding forest floors. Species diversity, maximum species diversity, and the evenness of slope facing north were analyzed to be high comparing to those facing east, west, and south according to azimuth of slope. Species diversity, maximum species diversity, evenness of slope, and the plant succession of surroundings were analyzed to be high when the gradient of the slope was less than $40^{\circ}$. The dominant species which success on the slope of an expressway and its surrounding forest area included Miscanthus sinensis var. purpurascens, Zoysia japonica, Pinus thunbergii Parl, Rubus crataegifolius, Lespedeza cyrtobotrya, Amorpha fruticosa, Artemisia princeps var. orientalis, and Oenothera biennis.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.4
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• pp.11-19
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• 2022

In this study, in order to improve the splice performance of mechanical couplers, two new mechanical couplers with different connection modes were developed with rebar(SD400). The stress analysis of mechanical couplers with two different connection modes was carried out. Uniaxial tensile tests were carried out with type of steel, connection mode and the slope length of internal fastener as variables to analyze the influence on the maximum tensile strength. Building upon this previous work, the specimens that met the code in uniaxial tensile test were fabricated and static loading test and cyclic loading test were performed on the basis of Korean code(KS D 0249). The results of this research are as follows; (1) The tensile strength of steel and the slope length of internal fasteners have a certain influence on the maximum tensile strength. (2) The connection mode has some influence on the stiffness, slip and stiffness reduction rate of the connecting rebars. The results verify the feasibility of the proposed enhanced mechanical coupler in the field.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.3
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• pp.83-92
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• 1999

To investigate the influence of forest road characteristics and site conditions on the stability of forest-road in granite area, four forest roads had been selected in Kyongbuk regions. The total of 13 road characteristic variables were evaluated by the discriminant analysis. The factors influencing the stability of forest road were bed rock, slope length, coverage, hardness, side-ditch erosion and road width. But aspect and soil texture were not significant for the stability in this area. In the correlation between forest environment and road structure, hardness and bed rock was highly significant in stability group, and coverage and side-ditch erosion was highly significant in instability group. 75 of 175 segments were instable whereas the others were stable. The centroids value by discriminant function in the stability and instability were estimated to 3.0585 and -1.9116, respectively. The stability criterion of forest road was discriminated from the centroids value of the each group. The main factors contributing the stability of forest road were significant in order of side-ditch erosion, coverage, soil texture, elevation, gradient, slope length and construction year. The prediction rate of discriminant function for stability evaluation of forest road was as high as 97.44%. In conclusion, the forest road structure factors such as length, coverage and slope gradient were controlled by construction techniques. If the factors like those should be considered in design, construction and forest road management, the stability of forest road may increase more. And also, it is necessary to take slope protection measures like small terraces and retaining walls for stability of cut slope.