• Proceedings of the Korean Geotechical Society Conference
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• 1998.10a
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• pp.267-274
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• 1998

• The Pure and Applied Mathematics
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• v.2 no.2
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• pp.149-156
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• 1995

In stability theory of polysystems two concepts that playa very important role are the limit set and the prolongational limit set. For the above two concepts, A.Bacciotti and N.Kalouptsidis studied their properties in a locally compact metric space [2]. In this paper we investigate their results in c-first countable space which is more a general space than a metric space.(omitted)

• Journal of the Korean Geosynthetics Society
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• v.5 no.4
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• pp.11-18
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• 2006

Geotextile has been used for various types of containers, such as small hand-filled sandbags, 3-dimensional fabric forms for concrete paste, large soil and aggregate filled geotextile gabion, prefabricated hydraulically filled containers. They are hydraulically filled with dredged materials and have been applied in coastal protection and scour protection, dewatering method of slurry, temporary working platform for bridge construction, temporary embankment for spill way dam construction. Recently, geotextile tube technology is no longer alternative construction technique but suitable desired solution. The paper presents the stability behavior of geotextile tube composite structure by 2-D limit equilibrium and slope stability analysis. 2-D limit equilibrium analysis was performed to evaluate the stability of geotextile tube composite structure to the lateral earth pressure and also transient seepage and stability analysis were conducted to determine the pore pressure distribution by tide variation and slope stability. Based on the results of this paper, the three types of geotextile tube composite structure is stable and also slope stability of overall geotextile tube composite structures is stable with the variation of tidal conditions.

• Proceedings of the Korean Geotechical Society Conference
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• 1998.03a
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• pp.381-386
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• 1998

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.485-492
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• 2003

In this study, We peformed on the effective evaluation of slope berm construction using slope stability analysis programs. The effective evaluation of slope berm construction was performed by stability of slope and economy of construction. This time, used slope stability analysis programs are Talren97 that use Limit equilibrium method (LEM) and FLAC-SLOPE that use finite difference method (FDM), and carried out using Rocfall program to evaluate slope stability by rockfall occurrence.

• The Journal of the Korea Contents Association
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• v.13 no.4
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• pp.273-280
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• 2013

This study aims to examine the influences of wearing an occlusal biteplane splint on balance of the body. 10 subjects were selected who had neither impaired occlusion and masticating systems nor difficulty in walking along with no medical history in temporomandibular joint. Measurements were conducted with the Fukuda stepping test, the limits of stability test. The level of significance, ${\alpha}$ to determine the statistical significance was .05. Fukuda stepping test and the limits of stability test were put to the Wilcoxon signed test. As a result of this study, there was a significant difference in the moving distance in the Fukuda stepping test (p<.05). In addition, there were significant differences in the results of the limits of stability test (p<.05). In conclusion, the results of this study suggest that wearing the occlusal biteplane splint has an positive influence on the balance of the boby.

• Journal of Electrical Engineering and Technology
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• v.6 no.4
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• pp.474-483
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• 2011

Solid-state fault current limiters (SSFCL) in power systems are alternative devices to limit prospective short circuit currents from reaching lower levels. Fault current limiters (FCL) can be classified into two categories: R-type (resistive) FCLs and L-type (inductive) FCLs. L-type FCL uses an inductor to limit fault level and is more efficient in suppressing voltage drop during a fault. In contrast, R-type FCL is constructed with a resistance and is more effective in consuming the acceleration energy of generators during a fault. Both functions enhance the transient stability of the power system. In the present paper, a novel SSFCL is proposed to enhance power system transient stability and power quality. The proposed SSFCL uses both functions of an L-type and R-type FCL. SSFCL consists of four diodes, one self-turn-off IGCT, a current-limiting by-pass inductor (L), and a variable resistance parallel with an inductor for improvement of power system stability and prevention of over-voltage across SSFCL. The main advantages of the proposed SSFCL are the simplicity of its structure and control, low steady-state impedance, fast response, and the existence of R-type and Ltype impedances during the fault, all of which improve power system stability and power quality. Simulations are accomplished in PSCAD/EMTDC.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.179-184
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• 2005

Shear strength parameters obtained from filed survey are important factors in the analysis of slope stability. In this study, sensitivity analysis was performed to evaluate the effect of input parameters on the analysis of slope stability. The input parameters selected for sensitivity analysis were slope angle, cohesion, and friction angle. Monte-Carlo Simulation method was used for calculating input parameters and the factor of safety was computed by means of limit equilibrium method. A rock slope, which has failed in the field, was used for the sensitivity analysis in the analysis of slope stability. The result of analysis shows that the factor of safety of the rock slope was a little low. From partial correlation coefficient(PPC) of input parameters determined from the sensitivity analysis, slope stability was dependant on cohesion and slope angle. The effect of friction angle was lower than that of cohesion and slope angle on slope stability.

• International Journal of Automotive Technology
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• v.7 no.5
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• pp.519-526
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• 2006

For investigating the effect of fuel stratification on flame propagation, initial flame development and propagation were visualized under different axially stratified states in a port injection SI engine. Stratification was controlled by the combination of the port swirl ratio and injection timing. Experiments were performed in an optical single cylinder engine modified from a production engine and images were captured through the quartz window mounted in the piston by an intensified CCD camera. Firstly in this paper, the characteristics under no port-generated swirl condition, i.e. normal conventional case was studied. Under various stratified conditions, flame images were captured at the pre-set crank angles. These were averaged and processed to characterize the flames propagation. The flame stability was estimated by the weighted average of flame area and luminosity. The stability was also evaluated through the standard deviation of flame area and propagation distance, and mean absolute deviation of propagating direction. Results show that stratification state according to injection timing do not affect on the direction of flame propagation. The flame development and the initial flame stability are strongly dependent on the stratified conditions and the initial flame stability is closely related to the engine stability and lean misfire limit.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.5
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• pp.169-173
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• 2004

This paper presents the basic application idea of superconductor cable for voltage stability limited power system. In bulk power system, the transfer capability of transmission line is often limited by the voltage stability, and superconductor cable could be one of the countermeasure to enhance heat transfer limit as well as voltage stability limit. Steady state voltage stability approach by P-V curve is used to calculate the maximum transfer capability of initial system and superconductor applied system. IEEE-14 bus system is used to demonstrate its applicability.