Abstract Dielectric barrier discharge (DBD) in air, which has been established for the production of large quantities of ozone, is more recently being applied to a wider range of aftertreatment processes for HAPs (hazardous air pollutants). Although DBD has high electron density and energy, its potential use as precharging nano and submicron sized particles, is not known. In this work, we measured V‐I (voltage‐current) characteristics of DBD and estimated the collection efficiency of particles with bimodal distribution by DBD type 2‐stage ESP (electrostatic precipitator). To examine the particle collection with various applied voltage waveforms of DBD, nano size particles of NaCl (20∼100 nm) and DOS (50∼800 nm) were generated by an electrical tube furnace and an atomizer, respectively. Particle collection efficiencies of all the cases increased with increase of DBD electric power that the results corresponded to product of V by I whose magnitudes were the largest in triangular voltage waveform.

Decomposition of ozone at room temperature was investigated by comparing between commercial monolithic ozone decomposition catalyst (ODC, MnO2) filter and monolithic photocatalyst (TiO2) filter. The effects of residence time, UV (ultraviolet, A type) irradiation, and upstream ozone concentration on the ozone conversion were discussed. UV ray was irradiated using four BLB (black light blue) lamps (λ: 310∼ 400nm) of constant intensity. The upstream concentration of ozone was controlled by an electrostatic ozone generator. For ODC performance, the presence of UV irradiation slightly affected initial ozone conversion compared with no UV irradiation condition. However, for photocatalyst, the ozone was highly decomposed in the presence of UV irradiation. Long time performances of the both catalysts were evaluated by a real-time ozone monitoring system during 120 hours. The results show that the UV irradiation enhanced the ozone conversion for the both catalysts.

본 연구에서는 자료동화기법의 하나인 확장 칼만 필터를 이용하여 유량자료의 실시간 품질향상을 수행하였다. 확장 칼만 필터의 상태-공간모형은 강우-유출모형과 관측유량자료를 이용하여 구성하였다. 본 연구에서는 실시간 품질향상 목적을 댐 유입량의 비정상적 고변동성 억제 및 관측유량의 결‧오측 보완으로 구분하였으며, 각각의 경우에 적절한 확장 칼만 필터 모형을 제시하였다. 이들 모형의 차이는 칼만이득 계산에 필요한 공분산 함수의 추정에 변동성만을 고려하는냐 또는 편의까지를 포함하느냐로 나타난다. 본 연구는 충주댐 유역을 대상으로 적용하였으며, 그 결과 제시된 모형들이 댐 유입량자료나 결‧오측이 포함된 유량자료의 실시간 품질향상에 효과적으로 작동함을 확인하였다.