• Proceedings of the KIEE Conference
• /
• 2005.07c
• /
• pp.2214-2216
• /
• 2005

This paper is researched discharge and ozone generation characteristics of ozonizer using $Al_2O_3$ Ceramic dielectric. The discharge characteristics with variation of the discharge electrode area is studied. The characteristics of ozone concentration. ozone generation and ozone yield were measured to discharge power, discharge electrode area and supplied gas flux for oxygen and air. The solubility of ozone for water concentrations and ozone generations proportional to discharge power and discharge electrode area. Ozone yield has slowly increase with Increasing discharge power at high flow-rate. As the result, the maximum values of ozone characteristics ozone generation and ozone yield, can be obtained 5817[ppm] and 36[g/kWh]. We make enough the ozone concentration as the air in the home. An electric discharge electrode area is apt to shrink gradually into a miniaturization trend of the ozonizer but the enlargement of the occurrence flight of the electric discharge area gives the characteristic enhance the aid in the identity condition through the structure improvement.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.41 no.12
• /
• pp.13-19
• /
• 2004

We have been studied on the high concentration ozonized water production technology which substitute for the SPM wet cleaning solution process as the PR strip process after the photolithography process in the semiconductor and flat panel display manufacturing. In this work, we have developed the surface discharge type ozone generator which has the characteristics of the 12 ［wt%］ ozone concentration at the oxygen gas flow of 0.5［ℓ/min］ oxygen per cell and also developed the high efficiency ozone contactor for the mixing ozone gas with deionized water. As the production test results of the ozonized water, we obtained the ozonized water concentration above 80［ppm］ at the 10［wt%］ ozone gas concentration, and also had a good result of the PR strip rate of 147［nm/min］. at the 70［ppm］ ozonized water.

• Journal of Korean Society for Atmospheric Environment
• /
• v.18 no.4
• /
• pp.253-264
• /
• 2002

Surface ozone concentrations measured at 40 monitoring sites in three major cities (Seoul, Busan, and Daegu) of Korea during 1993~2000 were analyzed to understand the characteristics of temporal and spatial distributions. Trends were analyzed for annual mean, 95th percentiles of daily 8-hour maximum and days exceeding 8-h ozone standard of 60 ppb. Three indicators exhibited increasing trends (+0.75 ppb yr$^{-1}$ , +2.20 ppb yr$_{-1}$ , and +5.35 days yr$_{-1}$ on average) throughout the study period at all cities. Diurnal and seasonal variations were the largest in Seoul followed by Daegue and Busan, due to the high photochemical production and titration of ozone (Seoul), strong wind and constant supply of background ozone from the ocean (Busan). In the urban centers and industrial areas at all cities, scavenging of ozone by NO reduces the daily 8-hour maximum ozone by 10 ppb on average. High concentrations of ozone have frequently occurred in downwind eastern (Seoul and Daegu) or northern (Busan) sides of the territory. In particular, the coastal area of Busan had relatively high ozone level due to the local sea land breeze circulation. The results indicated that the temporal and spatial variations of ozone concentration were non -uniform and were closely related to the local environments; emission levels, climates, and geographic locations.

• Journal of Korean Society for Atmospheric Environment
• /
• v.11 no.3
• /
• pp.253-262
• /
• 1995

A study has been performed on the characteristics of rural and urban surface ozone concentration for the period of March 1992 to February 1993. The monitoring station of rural ozone is located at Kosan, Cheju and other urban monitoring stations are located at Seoul, Pusan and Kwangju. Rural's and urban's ozone data exhibit a distinct features in many ways. First, annual mean of rural ozone concentration os very high(42 ppbv) but urban's are very low(10 .sim.15 ppbv). Second, rural ozone data shows a seasonal variation with it's maximum in spring, and minimum in summer, but urban's show a seasonal variation with it's maximum in spring, and minimum in winter. Third, diurnal variation of rural data is very small but that of urban's are very large. Fourth, urban's data are extremely low(< 3 ppbv) and have no seasonal variations.

• Journal of Environmental Health Sciences
• /
• v.41 no.2
• /
• pp.71-81
• /
• 2015

Objectives: Photochemical ozone pollution is associated with increased mortality risk. This study aims to assess the population exposure to ozone according to population characteristics for high ozone days in the Busan metropolitan region (BMR). Methods: The ozone exposure assessment in this study was performed using the WRF-CMAQ simulated ozone concentrations and the population data in the BMR. The settled and daytime population and their activity were considered to conduct the static and dynamic ozone exposure assessment. Results: Applying a static exposure assessment, in case that high ozone occurred throughout Busan area, the highest exposure levels were evaluated in urban neighborhoods. In case of ozone pollution in outer Busan, because sensitive groups have been relatively higher exposure, this case was also evaluated as part of that should not be overlooked. The dynamic exposure was higher than static exposure because the number of population exposed to ozone of high concentration is increased. This approach is important in a regard consider that daytime population distribution when high ozone occur. Conclusion: This study shows the different population exposure according to various ozone distributions for each episode day. Considering demographic characteristic such as population density and activity should be important to understanding the population exposure assessment when ozone pollution occurs.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.13 no.2
• /
• pp.203-203
• /
• 1999

In this paper, high concentration·yield multi-discharge type ozonizer( MDO ) of new discharge type using superposed silent discharge was designed and manufactured. MDO can be consisted with 3 kind of superposed silent discharge type ozonizer( SDO ) in accordance with power supply method that supplying power, which has 180[°] phase difference, to 3 electrodes and double gap. At the moment discharge characteristics and ozone generation characteristics of each SDO were investigated in accordance with quantify of supplied gas, the number of SDO, and the shapes of each SDO. In result ozone generation characteristics of 17185[ppm] and 783[g/kWh] were obtained, and whorl ozone of 17185[ppm] was in contact with dyeing water waste decolonization characteristics was excellent, so it confirmed that MDO could be used as water environment improvement facility.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.20 no.11
• /
• pp.977-982
• /
• 2007

The realization of the photoresist(PR) removal method with vaporized water and ozone gas mixture has been studied for the LCD TFT array manufacturing. The developed PR stripper uses the water boundary layer control method based on the high concentration ozone production technology. We develop the prototype of PR stripper and experiment to find the optimal process parameter condition like as the ozone gas flow/concentration, process reaction time and thin boundary layer formation. As a results, we realize the LCD PR strip rate over the 0.4 ${\mu}m/min$ and this PR removal rate is more than 5 times higher than the conventional immersion type ozonized water process.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.4 no.1
• /
• pp.29-37
• /
• 2002

This study was conducted to compare ozone sensitivity among Betula sp. by measuring visible foliar injuries and growth responses. Four Betula sp.(B. costata, B. davurica, B. platyphylla var.japonica and B. ermani) grown in the greenhouse, were transplanted in the plastic pots. One-year-old seedlings of four Betula sp. exposed to relatively high ozone concentration(100 ppb) for 8 h day$^{-1}$ for 5 weeks in fumigation chamber. We measured visible injuries, leaf numbers and leaf areas at the end of experiments, and growth effects were evaluated by measuring the relative growth rate(RGR) of height and diameter and the dry weights of leaf, stem and root once a week. Four Betula species showed the significant differences for growth responses by the ozone treatment. Growths of three species, except for B. ermani, were significantly reduced by the $O_3$ exposure. B. costata with leaf senescence at the early growing stage and B. davurica indicated highest visible foliar injury rate may be the sensitive species at the 100 ppb ozone concentration. Although the growth rate of B. ermani was reduced by 100 ppb ozone exposure at the early growing stage, B. ermani may be a tolerance species that recover the growth rate with the adaptation for the high ozone concentration.

• Journal of Korean Society for Atmospheric Environment
• /
• v.27 no.1
• /
• pp.50-62
• /
• 2011

Temporal trends and spatial distributions of ozone concentrations in Pohang were investigated using data measured at 4 air quality monitoring stations (i.e., Daedo, Jukdo, Jangheung, and Desong) during 2002-2006. The monthly mean ozone concentrations were highest during April and June and decreased during July and August, which follows the typical trend in the Northeast Asia region. The high springtime ozone concentration might have been strongly influenced by the enhanced photochemical ozone production of accumulated precursors during the winter under increased solar radiations. In July and August, ozone levels were decreased by frequent and severe precipitation that caused lower mean monthly solar radiation and efficient wash-out of ozone precursors. This suggests that precipitation is extremely beneficial in the aspect of ozone pollution control. High ozone concentrations exceeding 80ppb dominantly occurred in May and June during the late afternoon between 16:00~17:00. Ozone concentrations were higher in Jangheung and Daesong relative to Daedo and Jukdo, whereas total oxidants $(O_3+NO_2)$ were higher in Jangheung and Daedo. In the suburban area of Daesong, ozone concentrations seem to be considerably higher than those in urban sites of Daedo and Jukdo due to lower ozone loss by NO titration with lower local NO level.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.44 no.1
• /
• pp.22-27
• /
• 2007

we have been studied on the realization of the boundary layer controlled ozone process and related facilities in order to apply for the photo-resist strip process in the semiconductor and flat panel display manufacturing. By means of developing the technology for the high concentration ozone production, it was possible to realized the boundary layer control ozone process by vapor. As a result of the silicon wafer PR strip test, we obtained the strip rate of about 400nm/min at the ozone concentration of 16wt% and flow rate of 8[liter/min.].