• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.4
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• pp.435-442
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• 2007

To reduce damage from high concentration ozone in the air, we have researched how to predict high concentration ozone before it occurs. High concentration ozone is a rare event and its reaction mechanism has nonlinearities and complexities. In this paper, we have tried to apply and consider as many methods as we could. We clustered the data using the fuzzy c-mean method and took a rejection sampling to fill in the missing and abnormal data. Next, correlations of the input component and output ozone concentration were calculated to transform more correlated components by modified log transformation. Then, we made the prediction models using Dynamic Polynomial Neural Networks. To select the optimal model, we adopted a minimum bias criterion. Finally, to evaluate suggested models, we compared the two models. One model was trained and tested by the transformed data and the other was not. We concluded that the modified transformation effected good to ideal performance In some evaluations. In particular, the data were related to seasonal characteristics or its variation trends.

• Membrane Journal
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• v.11 no.4
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• pp.179-189
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• 2001

Effect of ozonation on permeate flux was studied by using polysulfone ultrafiltration membrane. The filtration was first carried out by permeating phenol solutions under 3$kg_{f}$/$cm^2$ until steady-state flux was obtained. Then, the ozone of concentration range between 10 and 45 mg/1.min was ozonated in water for reducing the fouling on the UF membrane. Treatment of chemical wastewater by combined ozone and membrane filtration methods was also investigated for the final purpose. The Fenton method assisted by chemical coagulation was employed as a prtreatment method and found to be highly efficient in removing a large amount of organic compounds. And it was found that the ozonation made the permeate flux enhance in the phenol solution and phenolic-chemical wastewaster by 10% and oxidation by ozone and hydrogen peroxide was more effective. Evidence was presented that TMP decreased in more ozone concentrated water and it was found that the ozone-mediated membrane would have a limited role to prevent the membrane fouling rather than to eliminate fully.

• Elastomers and Composites
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• v.16 no.4
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• pp.217-227
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• 1981

오존은 PE나 고무 등 고분자재료(高分子材料)의 표면(表面)에 존재하는 이중결합(二重結合)에 대(對)하여 친전자적부가반응(親電子的付加反應)으로 ozonide가 생성되고 이어서 제(第)3급(級) 수소(水素)를 공격하므로서 주쇄(主鎖)가 절단된다. 따라서 aldehyde, ketone 등의 carbonyl 화합물(化合物)이 생성된다. 이들이 재료표면(材料表面)의 굴곡변형(變形)의 증가에 따라 열(熱) 또는 공(光)에 의하여 다시 분해(分解)를 촉진시킨다. 2개(個)의 N분자(原子)에 방향족(芳香族) 및 지방족기(脂肪族基)를 각각 치환시킨 p - phenylene diamine 유도체(誘導體) 등과 같은 전자공흥성(電子供與性)이 큰 화합물(化合物)은 친전자적(親電子的)인 오존과 우선적으로 3급(級) 수소에 비하면 약 100 배(倍)로 반응성이 크다는것을 표(表)3으로 알수 있다. 미단이중결합(未端二重結合)에 대한 오존과의 반응은 다음 반응식과 같이 이중결합(二重結合)에 오존의 부가반응(付加反?)으로 개시(開始)되어 peroxi methylene이 유리되면서 미단(未端)은 aldehyde로 변화한다. 또 1개의 반응은 제(第)3급(級) 탄소-수소 결합에 오존이 삽입되고 계속 일어나는 분해반응으로서 hydroperoxide의 생성 및 탈염화수소(脫鹽化水素)반응이 일어난다. 이와같은 반응(反?)으로 생성(生成)된 내부(內部) 이중결합(二重結合)에 대한 오존의 반응은 olefin의 경우와 마찬가지로 molozonide나 ozonide의 과정을 거쳐 주쇄(主鎖)가 개열(開裂)되는 것이다.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1452-1456
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• 2008

우리나라 주요 상수원인 낙동강, 금강 등의 수질이 급격히 악화됨에 따라, 기존의 정수방법에 어려움이 발생되고 있다. 과거 염소에 의존한 수처리방법이 많이 사용되어 왔으나, 1989년 이후 중금속, THM(Trihalomethane), 페놀사건, 벤젠 등 각종 수돗물 유기물질 오염사고가 다발하면서, 활성탄 및 오존$(O_3)$ 등을 이용한 다양한 처리 시설들이 도입되기 시작했다. 이중 강력한 산화력을 지니고 있는 오존의 경우, 상수처리, 폐 배수처리, 식품의 살균 및 보관, 나아가 반도체 제조공정중의 포토레지스터의 제거에 이르기까지 폭넓게 사용되고 있다. 그러나 오존이 가지는 뛰어난 정화능력에도 불구하고, 막대한 설치비용 및 운전비용의 문제로 하수처리장과 같은 대규모 시설에서는 도입되지 못하고 있었다. 이러한 문제점을 극복하고자 본 연구에서는 재생 가능한 에너지를 오존시스템의 전력원으로 대용시킴으로써, 그 효과를 극대화시키고자 하는데 목적이 있다. 에너지 밀도가 낮지만, 지역 의존성이 적고, 청정한 무한 에너지인 수력, 풍력 및 태양에너지를 혼용한 오존 발생시스템은 소규모의 연못이나 농촌의 저수지 같은 유역뿐만 아니라, 농촌폐수로 인해 오염된 지하수의 국소지역에 대한 수처리에 사용될 수 있다.

• The Journal of Natural Sciences
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• v.9 no.1
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• pp.9-17
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• 1997

We studied on the decoloring efficiency of a dying and finishing industrial wastewater containing reactive dyes in the ozone treatment system. The wastewater containing reactive dyes improved the decolorization by the ozone oxidation. In order to determine the optical conditions for ozonation, various operation factors such as initial wastewater concentrations, pH, temperature, and ozone dose were evaluated. Ozone utilization rate was improved in general with the increase of initial concentration of wastewater. And the decolorization speed or reactive dyes was more decreased in deep color of blue series than in light color such as yellow series. The colorization of wastewater containing reactive dyes was changed step through midle color depending upon increasing of ozone treated time. The efficiency of decolorization for wastewater was improved with the pH increased and the temperature of ozone treatment system decreased.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.2
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• pp.68-74
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• 2000

In this paper the concentration, yield and generation quantity of the ozone by the superposition discharge according to the coaxial electrodes geometry is described. In order to improve the ozone generation, a new type of ozonizer is proposed, where a silent discharge and a surface discharge are generated in the separated discharge spaces at the same time. To investigate the ozone generation dependency on electrode geometry, a few discharge tubes with different geometry were fabricated. In our experiment, the 60[Hz] one phase voltage is applied to the discharge tube which has three electrodes. And three kinds of discharges, two silent discharges and a surface discharge are superposed in the same space of the ozonizer. As a result, the followings are obvious. When two kinds of discharges are superposed under the condition using 3 electrode-3gap discharge tube, the maximum ozone efficiency is obtained.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.1
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• pp.149-156
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• 2008

Recently, ozone is utilized in various fields and its needs are expanding. In this paper, plate type ozonizer have been fabricated to investigate discharge parameter(input power, flow rate of supplied gas, electrode form, etc.) effect to discharge. And the conditions of discharge parameter have been investigated for optimum ozone generation. Ozone concentration is continuously increased with increasing input power for same discharge space, and ozone yield is also increased until maximum point after that it is saturated. Ozone concentration is inversely proportional to flow rate of supplied gas but ozone generation and ozone yield characteristics are improved.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.5
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• pp.460-466
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• 2001

The oxidizing power of ozone is the greatest of all commercially available oxidizers and thus ozone is taking the place of chlorine for water treatment. For energy-effective treatment of water, ozone should be generated in high concentration. A silent glow discharge ozonizer is high effective in industrial aspect and thus is the most widely used. We found that the key parameters associated with the ozone generation rate are the driving voltage of the discharger, the discharge rate and the temperature of the ozone generation tube. For an easy control of these parameters, we build a monitoring system with graphical user interface. This system is based on Windows-98 PC, programmed with C++ and LabView.

• Journal of the Korean earth science society
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• v.21 no.3
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• pp.287-301
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• 2000

In order to investigate the factors and processes affecting the vertical distributions of ozone, we analyzed the ozone profile data measured using ozonesonde from 1995 to 1997 at Pohang city, Korea. In the course of our study, we analyzed temporal and spatial distribution characteristics of ozone at four different heights: surface (100m), troposphere (10km), lower stratosphere (20km), and middle stratosphere (30km). Despite its proximity to a local, but major, industrial complex known as Pohang Iron and Steel Co. (POSCO), the concentrations of surface ozone in the study area were comparable to those typically observed from rural and/or unpolluted area. In addition, the findings of relative enhancement of ozone at this height, especially between spring and summer may be accounted for by the prevalence of photochemical reactions during that period of year. The temporal distribution patterns for both 10 and 20km heights were quite compatible despite large differences in their altitudes with such consistency as spring maxima and summer minima. Explanations for these phenomena may be sought by the mixed effects of various processes including: ozone transport across two heights, photochemical reaction, the formation of inversion layer, and so on. However, the temporal distribution pattern for the middle stratosphere (30km) was rather comparable to that of the surface. We also evaluated total ozone concentration of the study area using Brewer spectrophotometer. The total ozone concentration data were compared with those derived by combining the data representing stratospheric layers via Umkehr method. The results of correlation analysis showed that total ozone is negatively correlated with cloud cover but not with such parameter as UV-B. Based on our study, we conclude that areal characteristics of Pohang which represents a typical coastal area may be quite important in explaining the distribution patterns of ozone not only from surface but also from upper atmosphere.

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.2
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• pp.72-79
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• 2002

This study was conducted to compare the physiological and biochemical responses of four Betula species in response to ozone, and to find out the relationship between ozone uptake rate and photosynthesis or antioxidant activity. One-year-old seedlings of four Betula sp, B. costata, B. davurica, B. platyphylla var, japonica, and B. ermani, exposed to 100 pub ozone concentration for 8h day$^{-1}$ for 5 weeks in fumigation chamber. Ozone uptake rate, photosynthesis, SOD and GR activity were measured in the leaves of four species once a week. Cumulative ozone uptake rate was largest in the loaves of B. costata(53.8 mmol m$^{-2}$ ), smallest in the leaves of B. davurica(35.5 mmol m$^{-2}$ ). Photosynthesis of four Betula sp. exposed to ozone reduced relative to control, but the photosynthetic responses with changing stomatal conductance were different among species. Ozone exposure increased SOD activities of four species at the early exposing period, but after a critical point SOD activity decreased gradually. GR activity of B. costata was similar to the change of SOD activity, but the others showed the different patterns from B. costata. In conclusion, decreasing both SOD and GR activity at the critical point, B. costata may be sensitive species in response to ozone. In contrast, the others may be resistant species, which gradually increase GR activity following ozone exposure. GR activity was not always in accord with the change of SOD activity against ozone uptake, and the different responses between species were supposed to be affected by the cumulative ozone uptake.