• Journal of Korean Society of Environmental Engineers
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• v.35 no.10
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• pp.749-755
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• 2013

The purposes of this research are to know the optimal gab and electric pressure (voltage) of electrode-plates coated with activated carbon and also to study their arrangement through dust removal efficiency. From the experimental results of attached dust mass at different electrode-plate gab, the frequency of attachment and detachment of dust was more increased as electrode-plate gab was closer. In attached dust mass per unit area of electrode-plate, the farther electrode gab, the more increased. But in total attached dust mass, the closer electrode gab, the more removed. From the experimental results, the optimal electrode arrangement in dust removal chamber was considered that the forward parts of chamber need to be increased the number of electrode-plate, the backward parts to be increased them. The dust attachment have no relation with electric pressure while showing high removal efficiency under condition of 5 kV of voltage and 2 cm of electrode-plates gab.

• Journal of the Korean GEO-environmental Society
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• v.22 no.11
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• pp.31-37
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• 2021

To prevent accidents due to the cavities and loosened layers formed due to water leakage from the deteriorated buried pipes, evaluation of the changes in water contents around the buried pipes is required. As a method to evaluate the water contents of the soils, time domain reflectometry (TDR) system can be adopted. However, slender electrodes used in standard TDR probe may be damaged when buried in the ground. Thus, in this study, buried type TDR module was developed for the evaluation of the water contents with maintaining required shape of the electrodes in the ground. The TDR module is composed of three electrodes connected to the core conductor and outer conductor and a casing to prevent deformation and maintain alignment of the electrodes in the ground. For the verification of TDR waveforms measured using the TDR module, comparative analysis was conducted with the TDR waveforms measured using the standard TDR probe, and the relationship between the volumetric water content of the soils and the travel time of the guided electromagnetic wave was constructed. In addition, a model test was conducted to test the applicability of the buried type TDR module, and the experimental result shows that the TDR module clearly evaluates the changes in volumetric water contents due to the leakage from the modeled buried pipe. Therefore, the buried type TDR module may be effectively used for the health monitoring of the buried pipe and the evaluation of the water contents around the pipes buried in the urban pavements.