• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.249-250
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• 2001

최근 대도시 지역에서의 오존농도가 환경기준을 초과하는 빈도가 날로 증가하고 있는 실정이며, 이에 국내의 경우 오존농도 증가에 대비하여 대기 중 오존농도가 일정기준(시간당 0.12 ppm)보다 높게 나타났을 때 신속하게 경보를 발령, 시민들의 건강과 생활환경상의 피해를 최소화하기 위해 오존경보제를 시행해오고 있다. 한편 전세계적으로 대도시 지역에서의 지표면 오존농도가 환경기준을 초과함에 따라 오존생성과 관련된 전구물질(precursor)에 대한 제어과정이 지표면 오존농도의 저감을 실현하기 위한 가장 시급한 과제로 대두되고 있으며, 특히 미국의 경우 1993년부터 광화학평가측정망(Photochemical Assessment Monitoring Stations;PAMS)을 설치하여 이들 물질에 대한 보다 집중적인 모니터링을 실시하고 있는 것으로 알려져 있다. (중략)

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.5 s.118
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• pp.24-30
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• 2006

This study was performed to characterize inverse emulsion type cationic polyacrylamide (PAM) and to compare with powder and salt dispersion type PAMs as a retention and drainage aid. Salt dispersion type PAM has defects of high amount of salt which increases conductivity of white water, low active polymer contents and relatively worse retention and drainage properties than others because of its low molecular weight. Powder type PAM has benefit of high active polymer contents and good retention and drainage properties, but defects of low dissolution speed and insoluble particle generation were observed. However, inverse emulsion type showed the best retention and drainage aids among them by controlling molecular weight and morphology easily and it had relatively higher active polymer contents and better solubility.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.04a
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• pp.954-957
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• 2010

슈퍼컴퓨터 시스템의 성능과 보유 용량이 증가함에 따라 전력소비, 전산실 냉각, 시스템 설치 공간, 유지비용 등의 여러 가지 문제가 대두되고 있다. 이러한 문제의 시작은 슈퍼컴퓨터의 성능증가에 따라 전력밀도가 증가하는 것과 관계가 있다. 그래서 제조사에서는 저전력 서버, 고효율 서버를 위하여 많은 노력을 기울이고 있다. 또한, 시스템 관리측면에서도 시스템 가상화, 통합화를 통하여 서버의 수를 줄여서 전력소비를 줄이는 방안도 나오고 있다. 본 논문에서는 24시간 365일 서비스를 하는 시스템을 위하여 시스템을 사용하지 않는 시간에는 전원을 끄고 작업이 시작되면 다시 서버에 전원을 공급하여 살리는 기능을 자동적으로 하는 전원자동관리 시스템(Power Automatic Management System, PAMS)을 설계하였다. PAMS는 서버 전력소비에서 70%를 차지하는 대기전력을 절감하는 효과를 기대할수 있다.

• Journal of Korean Society of Transportation
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• v.33 no.5
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• pp.449-460
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• 2015

The reliability of air quality evaluation results for green transportation could be improved by applying correct emission factors. Unlike previous studies, which estimated emission factors that focused on vehicles in laboratory experiments, this study investigates emission factors according to road types and time using real driving data. The real driving data was collected using a Portable Activity Monitoring System (PAMS) according to road types and time, which it compared and analyzed fuel consumption from collected data. The result of the study shows that fuel consumption on national highway is 17.33% higher than the fuel consumption on expressway. In addition, the average fuel consumption of peak time is 4.7% higher than that of non-peak time for 22.5km/h. The difference in fuel consumption for road types and time is verified using ANOCOVA and MANOVA. As a result, the hypothesis of this study - that fuel consumption differs according to road types and time, even if the travel speed is the same - has proved valid. It also suggests correction factor of emission factors by using the difference in fuel consumption. It is highly expected that this study can improve the reliability of emissions from mobile pollution sources.

• Ocean and Polar Research
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• v.24 no.4
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• pp.391-398
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• 2002

Trace organic contaminants in deep-sea sediments near Dokdo were analyzed. Total PAMs concentration ranged 14.8-314 ng/g dry weight and high molecular weight PAHs were dominant. The highest PAHs concentration was detected at A19 which located at Ulleung Basin. Most of organochlorines were under detection limit. Among the detected organochlorines, DDT compounds were dominant and followed by HCHs and HCB. Butyltin compounds and most of organophosphorus pesticides were not detected. Vertical distribution of PAHs showed typical sub-surface maximum and decreasing trends depending on depth. The highest PAHs concentration reached 454ng/g. Some organochlorines, DDT, HCH was detected and also showed decreasing trends. Other target organic pollutants were not detected in core sediments. Abnormally high level of PAHs concentration in A19 was discussed and the input sources were inferred to be the transport of sludge derived pollutant dumped at dumping site 'Byung' by deep current.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.6
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• pp.751-771
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• 2011

Biogenic Volatile Organic Compound (BVOC) emissions are estimated with BEIS3.12 (Biogenic Emissions Inventory System version 3.12) over the Seoul Metropolitan Area (SMA) and then used in CMAQ (Community Multiscale Air Quality) simulations for two high ozone episodes in 2004 and 2007 June. The first- and second-order sensitivity coefficients of ozone to BVOC emissions are estimated with High-order Decoupled Direct Method (HDDM) simulation in order to estimate the influence of BVOC emissions on ozone using the Zero-Out Contribution (ZOC) approach. ZOC analysis shows that relative contribution of BVOC emissions on daily maximum 1-hr ozone is as high as 30% for high ozone days above 100 ppb. However simulated isoprene concentrations were over-estimated by a factor of 2 when compared to the observations at the PAMS (Photochemical Air Monitoring Station) for the 2007 episode. When assumed that actual BVOC emissions are 50% less than estimated, the ZOC of BVOC emissions on daily maximum ozone drops by more than 10 ppb for the episode. The result indicates that uncertainty in BVOC emissions may have significant impact on high ozone prediction in the SMA.

• Journal of environmental and Sanitary engineering
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• v.13 no.3
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• pp.102-112
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• 1998

The fate of polynuclear aromatic hydrocarbons(PAMs) in soil has drawn increasing concern due to their toxic, carcinogenic, and mutagenic effects. These compounds have been most commonly carried into the soil in solvent, as in a coal tar or cresote. This study has been focused on the applicability of microwave treatment of soils contaminated by PAHs. Studies have been conducted with soil(particle diameter $150~500{\mu}m$), which was spiked with naphthalene, acenaphthene, fluorene, anthracene and pyrene, with different moisture contents. According to the results of the research, up to 95% removal efficiency of naphthalene was observed in 10% moisturized soil for five minutes microwave inducing And the removal efficiency of acenaphthene and fluorene were observed to be 88.9%, 67.2% in 30% moisturized soil, respectively. Due to the low vapor pressure, anthracene and pyrene showed the low removal efficiency. In case the powdered activated carbon was added to the soil as a sensitizer, anthracene and pyrene were decomposed into a various by-products. Decomposition rates of anthracene and pyrene were increased with incresing addition of a PAC to the soil. It is concluded that the developement of a microwave process to remediate soils contaminated with PAHs is foreseeable. But additional studies are also needed regarding continuous microwave heating process.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.7 no.1
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• pp.27-35
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• 1989

Sport photographing by the Stereo-Camera generally used in Europ, Japan, etc was applied to the traffic-accident analysis more preferreatially than the measuring with Tape where some problems are found in its accuracy and duribility. Time for photographing and that for measuring a datum point were compared causes for accidents were analyzed by spot drawing PAMS, with a patameter of an exclusively used drawing set, after 3-dimensions were first measured and computed in Stereo-model. Also the collision-angle, the direction of the handle and the quartity of loss after a clash were computed by using a accident vehicle as a model those data was suggested as a way of potential practical the accidents at large.

• Journal of Environmental Science International
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• v.13 no.10
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• pp.891-902
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• 2004

In order to predict air pollution and Yellow-sand dispersion precisely, it is necessary to clarify the sensitivity of meteorological field input interval. Therefore numerical experiment by atmospheric dynamic model(RAMS) and atmospheric dispersion model(PDAS) was performed for evaluating the effect of temporal and spatial resolution of meteorological data on particle dispersion. The results are as follows: 1) Base on the result of RAMS simulation, surface wind direction and speed can either synchronize upper wind or not. If surface wind and upper wind do not synchronize, precise prediction of Yellow-sand dispersion is strongly associated with upwelling process of sand of particle. 2) There is no significant discrepance in distribution of particle under usage of difference temporal resolution of meteorological information at early time of simulation, but the difference of distribution of particles become large as time goes by. 3) There is little difference between calculated particles distributions in dispersion experiments with high temporal resolution of meteorological data. On the other hand, low resolution of meteorological data occur the quantitative difference of particle density and there is strong tendency to the quantitative difference.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.4
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• pp.423-438
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• 2008

BEIS2 (Biogenic Emissions Inventory System version 2) and BEIS3.12 (BEIS version 3.12) were used to estimate hourly biogenic emissions over South Korea using a set of vegetation and meteorological data simulated with the MM5 (Mesoscale Model version 5). Two biogenic emission models utilized different emission factors and showed different responses to solar radiations, resulting in about $10{\sim}20%$ difference in the nationwide isoprene emission estimates. Among the 11-vegetation classes, it was found that mixed forest and deciduous forest are the most important vegetation classes producing isoprene emissions over South Korea comprising ${\sim}90%$ of the total. The simulated isoprene concentrations over Seoul metropolitan area show that diurnal and daily variations match relatively well with the PAMS (Photochemical Air Monitoring Station) measurements during the period of June 3${\sim}$June 10, 2004. Compared to BEIS2, BEIS3.12 yielded ${\sim}35%$ higher isoprene concentrations during daytime and presented better matches to the high peaks observed over the Seoul area. This study showed that the importance of vegetation data and emission factors to estimate biogenic emissions. Thus, it is expected to improve domestic vegetation categories and emission factors in order to better represent biogenic emissions over South Korea.