• Journal of the Korean Society for Railway
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• v.2 no.3
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• pp.46-53
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• 1999

In this paper, made was a study on a mesh generation method based on the pollution error. This method is designed for the control of the pollution error in any patch of elements of interest. It is a well-known fact that the pollution error estimates are much more than the local one. When the pollution error is significant, nothing can be said about the reliability of any estimator based on local computations in the patch. Reliable a posteriori error estimation is possible by controlling the pollution error in the patch through proper design of the mesh outside the patch. This design is possible by equally distributing the pollution error indicators over the mesh outside the patch. The mesh generated from the conventional feedback pollution-adaptive mesh generation algorithm needs many iterations. Therefore, the solution time is significant. But the remeshing scheme in the proposed method was used here. It was shown that the pollution-adaptive mesh improves the E.I., simply denoted as Effectivity Index, on the patch of interest, and the pollution error reduces less than the local error.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.437-440
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• 2008

In recent years, pollution load calculation has become a topic for research that resulted in the development of numerous GIS modeling methods. The existing pollution method for nonpoint source (NPS) can not be indentified and calculated the amount of the pollution precisely. This research shows that the association of typical pollutant concentrations with land uses in a watershed can provide a reasonably accurate characterization of nonpoint source pollution in the watershed using Expected Mean Concentrations (EMC). The GIS based pollution assessment method is performed for three pollutant constituents: BOD, TN, and TP. First, the runoff grid by means of the precipitation grid and runoff coefficient is estimated. Then, the NPS pollution loads are calculated by grid based method. Finally, the final outputs are evaluated by statistical technique. The results illustrate the merits of the approach. This model verified that GIS based method of estimating spatially distributed NPS pollution loads can lead to more accurate representation of the real world.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.10a
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• pp.34-42
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• 2001

In this paper, we study on a modified mesh generation method based on the pollution error estimate. This method is designed for the control of the pollution error in any patch of elements of interest. It is a well-known fact that the pollution error estimates are much more than the local one. Reliable a posteriori error estimation is possible by controlling the pollution error in the patch through proper design of the mesh outside the patch. This design is possible by equally distributing the pollution error indicators over the mesh outside the patch. The conventional feedback pollution-adaptive mesh generation algorithm needs many iterations. Therefore, the solution time is significant. But we use the remeshing scheme in the proposed method. We will also show that the pollution error reduces less than the local error.

• Journal of Environmental Science International
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• v.5 no.4
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• pp.399-410
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• 1996

Pusan is the largest coastal city with a population of about four mi18ion in Korea. Because of increased and confused traffic, photochemical air pollution become a major urban environmental problem recently. The photo-chemical air pollution weather forecasting method preciser than existing air pollution forecast method has been developed to forecast ozone episode days with meteorological conditions using the data measured at 7 air quality continuous monitoring stations from lune to September using 2 years (1994, 1995). The method developed in present study showed higher percentage correct and skill score than existing air pollution forecasting in KMA ( Korea Meteorological Administration).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05c
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• pp.6-9
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• 2001

In this research, a experiment was performed to evaluate the electrical properties of outdoor insulator with the pollution cycle method. Cycle test methods such as DCM of STRI, IEC 61109 compared with pollution cycle method. Using dimatic properties of Korea peninsula, we could get the optimal condition for the pollution cycle method. As the factor, clean and saline fog, voltage, rainfall and drying was chosen. The applied voltage is 13,2 kV, the salinity of salt solution was changed from 0.1 wt% to 1.5 wt% and one cycle is about 4 hours. To ensure the reproducibility and reliability, experiments repeated 4 times. The leakage current was measured with Lab VIEW and the ESDD was measured with brushwiping method. This experiment could ensure superiority of pollution cycle method which developed through the result of this experiment and we could know the relationship between ESDD, leakage current and relative humidity.

• Journal of Korean Society for Atmospheric Environment
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• v.3 no.1
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• pp.47-54
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• 1987

A new method for designing air pollution monitoring newtork is presented in this study. In this method, the magnitudes and the correlation coefficients of predicted concentrations in each grid points are examined and the monitoring stations are assigned to those stations which cover the damage cost the most. This method was applied to the Ulsan-Onsan Industrial Complex. This method turned out to be much more efficient than the method of TM coordinates and the method of concentric circles prescribed in the Standard Methods for Pollution Measurement as well as the existing monitoring system established in the area. The 21 stations selected by the method of TM coordinates could cover only 64.4% of the damage cost in the area, the 16 stations by the method of concentric circles 72.1%, and the existing 21 stations 67.8%, while 11 stations were enough to cover 90% of the damage cost in the area with this method. It also was found that this method required only 24 stations to cover the entire area.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1796-1803
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• 2015

While considering the current scenario, in this world power demand goes on increases day by day. Frequent power outages occur in high voltage transmission line due to the deprived performance of polluted insulators; this affects overall operation of power system and may indirectly impinge on the growth of production sector. Many researchers are keenly taking efforts to provide highly reliable and stable power to neediest. In this paper, A.C pollution flashover performance of disc type glass insulator and composite long rod insulators investigation under various artificial pollutions by varying Equivalent Salt Density Deposition (ESDD) levels. Here, we use different types of pollution methods like binding method, dipping method and spraying methods with different types of pollutants concentration. Based on dimensional analysis, four different Mathematical models have been developed to predict the A.C pollution Flashover Voltage (FOV) of insulators. Both the experimental and mathematically modeled results are compared; it's observed that mathematical model 3 yields better results.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.E
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• pp.23-29
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• 1995

Relationship between atmospheric aerosol transmissivity and air pollution was analyzed using observed data in a large industrial city, Pusan, Korea. The atmospheric aerosol transmissivity predicted by method of present study in Pusan was assessed by the method of Yamamoto et al.(1968) in order to set up an empirical model to predict the transmissivity using the various meteorological parameters and air pollution. As a result, good correlation between these tow method re observed. Thus, it is possible to conclude that the parameterization of air pollution suggested by this study is another method to give reliable estimate of atmospheric aerosol transmissivity and direct solar irradiance in Pusan.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.12
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• pp.21-26
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• 2011

This is a study to establish regulations against light pollution for lighting on roads. Many kinds of light pollution by luminaire on roads was calculated and analyzed by applying the classification method of luminaires(Cut-off classification of IDA-IESNA, BUG Rating Classification) and the calculation method of Upward Lighting Ratio of CIE among measures to prevent light pollution that international lighting organizations suggest. As a result of the analysis, it was found that the regulation by Cutoff of IESNA and ULR classification of CIE could be one for scattered light of light pollution compared to BUG classification but is not sufficient for the regulation of light tresspass or glare. BUG classification by each lighting zone was suggested as threshold value of the light pollution regulation considering domestic conditions.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.12
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• pp.27-33
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• 2011

This study aims to suggest some problems, which occur when environmental lighting zone is set by use-zone only, by comparing and analyzing the artificial illumination luminance. In addition, this study aims to review the control standards of light pollution and to suggest a practical environmental lighting zone-setting method. I checked out the standards of average surface luminance and luminance contrast as for light pollution management. In addition, I did some research on evaluation of light pollution on surroundings based on investigation of use-environment as for lighting environment setting method.