• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.54-58
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• 2006

This paper deals with primary consideration in down-conductor system and earth-termination system design of apartments. For down-conductor system, steelworks within reinforced concrete apartment structures have the electrical continuity, however, lashing is not suitable for lightning-current-carrying connections. So this paper suggest that the additional dedicated conductors should be installed and they are should be lashed to the reinforcement steel. Also this paper suggested the foundation earth electrode and global earth system as the earth-termination system of the apartments. But perfect bonding system is essential in lightning protection system to avoid life hazard and to protect electronic equipments.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.6
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• pp.637-647
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• 2019

In this study, we analyzed seismic behavior of reinforced earth retaining wall through the model test in order to characterize the behavior of reinforced earth retaining wall during earthquake. A scale model test was performed based on similitude ratio in accordance with law of similitude due to time and financial constraints on real scale modeling experiments. Seismic resistance characteristics of each seismic waves were analyzed by assessing the variations measured through excitation of the excited acceleration of 0.05g, 0.1g, 0.15g, and 0.2g. The results of this study, it would be important to obtain reasonable and abundant data on ground properties and seismic design in preparation for earthquakes when assessing the safety of block type reinforced earth retaining wall confined to model experiment. Acquisition of those data and systematic analytical techniques are considered likely to have a significant effect on the decrease of structure damage caused by earthquakes in Korea which has recently witnessed frequent occurrence of earthquakes.

• Journal of Soil and Groundwater Environment
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• v.29 no.2
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• pp.1-10
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• 2024

With industrial development, the inevitable increase in both organic and inorganic waste necessitates the exploration of waste treatment and utilization methods. This study focuses on co-pyrolyzing lignin and red mud to generate metalbiochar, aiming to demonstrate their potential as effective adsorbents for water pollutant removal. Thermogravimetric analysis revealed mass loss of lignin below 660℃, with additional mass loss occurring (>660℃) due to the phase change of metals (i.e., Fe) in red mud. Characterization of the metal-biochar indicated porous structure embedded with zero-valent iron/magnetite and specific functional groups. The adsorption experiments with 2,4-dichlorophenol and Cd(II) revealed the removal efficiency of the two pollutants reached its maximum at the initial pH of 2.8. These findings suggest that copyrolysis of lignin and red mud can transform waste into valuable materials, serving as effective adsorbents for diverse water pollutants.

• Journal of the Korean Geotechnical Society
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• v.15 no.4
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• pp.261-277
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• 1999

The horizontal and vertical earth pressures in backfill space which is narrowly excavated like ditch are affected by the share of ditch backfill space and the wall friction between excavated surface and backfill soil. In this paper, for the excavated surface the Handy's equation of a symmetric vertical case and the Kellogg's equation of a symmetric sloped one are modified to show the minor principal stress arch for the unsymmetrical excavated backfill space. Compared with the soil test box result, a similarity in magnitude and distribution of backfill earth pressure shows that the earth pressure has been observed. The backfill earth pressure in unsymmetrically sloped space has been shown twice as much as the one in vertically excavated space and also remarkable decline of arching for the former case. It is verified that the earth pressure equation should account the shape and size of backfill space to calculate the earth pressure for similar structure to the one handled in this study.

• Geotechnical Engineering
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• v.5 no.3
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• pp.39-50
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• 1989

A method is investigated to analyze the reliability of the gravity retaining wall which is designed to allow a limiting translational movement induces by the earthquake loading. Application of FOSM method to the Richards and Elms model yields a practical procedure for the analyses of the reliability and sensitivity of the retaining wall sujected to the earthquake. After examination of the practice (or the earthquake design of the retaining wall, the methods of the reliability analysis are considered. Finally, this study presents the step-by.step procedure for analyzing the reliability of the earth retaining structure for pratical convinience.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.06a
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• pp.3.1-11
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• 2003

Recently the problems related to the failure of the retaining wall structure has become great concern since the damage to the properties and human losses have occurred in the rainy season. However, a detail guideline on safety inspection and appropriate diagnosis on the retaining wall structure have not yet proposed and therefore, the inspection process and results are mainly dependant upon the engineers. The objective of this study is to propose objective and quantitative evaluation method for the condition based on the damage shapes and material types. In this purpose, composing materials of retaining wall are divided Into concrete, gabion, stone and reinforced earth, and then the evaluation items and method are suggested on the basis of the materials and structural characteristics of the retaining wall.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.878-881
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• 2001

In this paper, we analyzed the characteristics of insulating material with ELB(earth leakage circuit breaker) through tracking experiment and the study was carried out three different types of samples. The tracking is breakdown phenomenon of material surface that is generated on the organic insulating material. The test method applied IEC publication 587. The result of the sample breakdown by tracking was carbonized and resistance of between the electrodes is approximately 300$\Omega$. In the result of DSC analysis, the caloric peak was detected before 100$^{\circ}C$ in product of tracking. It appeared weight loss of 10.87% at 537$^{\circ}C$ on TGA. IR spectrum analysis showed carbon-hydrogen(C-H)bond on molecular structure that is the sample of tracking.

• International Journal of Advanced Culture Technology
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• v.7 no.4
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• pp.268-273
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• 2019

The apparent soil resistivity is used for estimating multilayer soil parameters, such as, layer's depth and soil resistivity. The soil parameters are estimated by continuously revising those parameters until the error between the measured and calculated apparent soil resistivity reaches to allowable level. The equation for calculating the apparent soil resistivity is complicated and time consumed, because it is composed of an infinite integral which includes a zero order Bessel's function of the first kind. In this paper, a fast algorithm for calculating the apparent soil resistivity of horizontal multilayer earth structure is proposed using exponential sampling method.

• Journal of The Korean Astronomical Society
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• v.37 no.5
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• pp.477-482
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• 2004

Shock waves form in the intergalactic space as an ubiquitous consequence of cosmic structure formation. Using N-body/hydrodynamic simulation data of a ACDM universe, we examined the properties of cosmological shock waves including their morphological distribution. Adopting a diffusive shock acceleration model, we then calculated the amount of cosmic ray energy as well as that of gas thermal energy dissipated at the shocks. Finally, the dynamical consequence of those cosmic rays on cluster properties is discussed.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.09a
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• pp.53-58
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• 2000

The KOESWall system that minimizes the horizontal deformation of reinforced wall effectively was developed bt E&S Eng. Co., Ltd. in 1999. Due to its systematical feature i.e. isolated construction method. KOESWall system is able to use as temporary structures more economically without the facing block. In this report, it is shown that the case history of KOESWall as a temporary soil retaining structure and the field measuremnets.