• 유기물자원화
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• 제23권3호
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• pp.78-84
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• 2015

본 연구에서는 표면 메탄농도와 지구통계기법(거리역산가중기법)을 기초로 표면 메탄발산량을 평가하고자 하였다. 실험결과 표면 메탄농도는 표면 메탄발산량과 높은 상관성이 있는 것으로 나타나, 표면 메탄농도를 기초로 표면 메탄발산량을 산정하는 것이 가능한 것으로 나타났다. 또한 지구통계기법 적용 결과 측정 면적의 12.85%가 총 메탄발산량의 42.21%를 나타내어 챔버 방법으로 메탄발산량을 정확하게 평가하기 위해서는 지구통계기법을 반드시 적용해야 하는 것으로 사료된다.

• Asian Journal of Atmospheric Environment
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• 제9권4호
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• pp.247-258
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• 2015

Exposure of high concentration of ground-level ozone (GLO) can trigger a variety of health problems including chest pain, coughing, throat irritation, asthma, bronchitis and congestion. There are substantial human and animal toxicological data that support health effects associated with exposure to ozone and associations have been observed with a wide range of outcomes in epidemiological studies. The aim of the present study is to estimate the spatial distributions of GLO using geostatistical method (ordinary kriging) for assessing the exposure level of ozone in the eastern part of Texas, U.S.A. GLO data were obtained from 63 U.S. EPA's monitoring stations distributed in the region of study during the period January, 2012 to December, 2012. The descriptive statistics indicate that the spatial monthly mean of daily maximum 8 hour ozone concentrations ranged from 30.33 ppb (in January) to 48.05 (in June). The monthly mean of daily maximum 8 hour ozone concentrations was relatively low during the winter months (December, January, and February) and the higher values observed during the summer months (April, May, and June). The higher level of spatial variations observed in the months of July (Standard Deviation: 10.33) and August (Standard Deviation: 10.02). This indicates the existence of regional variations in climatic conditions in the study area. The range of the semivariogram models varied from 0.372 (in November) to 15.59 (in April). The value of the range represents the spatial patterns of ozone concentrations. Kriging maps revealed that the spatial patterns of ozone concentration were not uniform in each month. This may be due to uneven fluctuation in the local climatic conditions from one region to another. Thus, the formation and dispersion processes of ozone also change unevenly from one region to another. The ozone maps clearly indicate that the concentration values found maximum in the north-east region of the study area in most of the months. Part of the coastal area also showed maximum concentrations during the months of October, November, December, and January.

• 한국실내디자인학회논문집
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• 제23권2호
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• pp.90-98
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• 2014

This study has analyzed the meaning of observation time in the course of acquiring the information of subjects who observed the space of hall in subway stations to figure out the process of spatial information excluded and the features of intensive searching. The followings are the results from the analysis of searching process with the interpretation of the process for information acquirement through the interpretation of observation area and time. First, based on the general definition of observation time, the reason for analyzing the features of acquiring spatial information according to the subjects' observation time has been established. The feature of decreased analysis data reflected that of observation time in the process of perceiving and recognizing spatial information, which showed that the observation was focused on the enter of the space during the time spent in the process of observing the space and the spent time with considerable exclusion of bottom end (in particular, right bottom end). Second, while the subjects were observing the space of hall in subway stations, they focused on the top of the left center and the signs on the right exit the most, which was followed by the focus on the both side horizontally and the clock on the top. Third, the analysis of consecutive observation frequency enabled the comparison of the changes to the observation concentration by area. The difference of time by area produced the data with which the change to the contents of spatial searching in the process of searching space could be known. Fourth, as the observation frequency in the area of I changed [three times -> six times -> 9 times], the observation time included in the area increased, which showed the process for the change from perception to recognition of information with the concentration of attention through visual information. It makes it possible to understand that more time was spent on the information to be acquired with the exclusion of the unnecessary information around.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2006년도 추계학술대회 논문집
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• pp.232-233
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• 2006

• 한국가시화정보학회지
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• 제14권1호
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• pp.51-56
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• 2016

Oxygen is a key factor in aerobic reactions and most biological activities. Visualization of oxygen distribution of a chemical process or biological system has been a very challenging object despite of its significance and potential impact. To monitor and visualize the spatial distribution of oxygen concentration, various techniques such as electro-chemical probe, polarographic electrode, LIF(laser-induced fluorescence) and so on have been introduced. Oxygen planar optode which utilizes the oxygen quenching of fluorescence light is one of the currently available methods for time-resolved visualization of oxygen distribution on a planar surface. In this study, we utilized VisiSens oxygen planar optode system to visualize the spatial distribution of oxygen concentration on leaves of Korean azalea. As a result, temporal variation of oxygen concentration distribution caused by respiratory activity of the leaf could be quantitatively monitored.

• 환경생물
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• 제37권3호
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• pp.299-308
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• 2019

2012년 8월 1일부터 7일까지 한국 남해 연안의 목포에서 부산에 이르는 37개의 정점에서 채집된 Acartia속 요각류의 공간 분포 양상에 대하여 분석하였다. A. erythraea는 용존산소가 2 mg L^-1 이하인 반 폐쇄적인(가막만, 마산만)만에서 높은 출현 개체수를 보였다. A. sinjiensis는 엽록소-a 농도가 2 ㎍ L^-1 이상인 반 폐쇄적인 만에서 높은 출현 개체수를 보였다. A. ohtsukai는 수온 26℃ 이상, 염분 30 이하일 때 높은 출현 개체수를 보였다. A. hongi, A. hudsonica는 수온이 27℃ 이하, 용존산소 5 mg L^-1 이상인 해역에서 출현하였다. 이러한 결과 환경요인이 여름철 남해 연안에 출현하는 Acartia속 요각류의 공간적 분포에 영향을 미칠 수 있음을 시사하고 있다.

• 한국대기환경학회지
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• 제29권1호
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• pp.10-26
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• 2013

To understand the traffic emissions with high temporal and spatial resolutions on road, a mobile laboratory was developed. The objective of this study is to characterize on-road air pollution on Naebu express way surrounding the northern area of Seoul, Korea. We measured the number concentration of ultrafine particles larger than 5 nm and particle size distribution using a condensation particle counter and a fast mobility particle sizer, respectively on 3, 7, and 8 December 2009. The average ultrafine particle number concentration on the Naebu express way excluding tunnels was 126,000 particles/$cm^3$ and 4.2 times higher than that on internal road at Korea Institute of Science and Technology in Seoul, and more than twice higher than that measured on and at the arterial roads of Seoul in previous studies. The maximum ultrafine particle number concentration was observed at the tunnel sections. It was 232,000 particles/$cm^3$ and 1.8 times higher than average ultrafine particle number concentration for the other sections on Naebu express way. The ultrafine particle number concentration on the wider roads with higher traffic volume along the Han River was similar to that in the residential section, probably because of enhanced dilution effect in widely open environment. The size distribution of particles on the Naebu express way was highly fluctuated for a short duration. Ultrafine particles measured at the tunnel showed a bimodal size distribution with mode diameters of ~10 nm and ~50 nm. At the Han riverside section, ~10 nm particles appeared significantly compared with size distribution at the tunnel. This on-road measurement approach can be utilized to manage vehicle-related air pollution in urban area.

• 환경영향평가
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• 제23권3호
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• pp.220-226
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• 2014

This study investigated temporal-spatial and variations in Geostationary Ocean Color Imager (GOCI) products of parameters total suspended solids (TSS) and chlorophyll-a in the North Marine Areas of East China Sea.GOCI data were collected daily from February 2012 to December 2012. The higher chlorophyll-a values were observed during the investigation period. The relatively large increase in TSS and chlorophyll-a at the sampling stations coupled with typhoon events during the summer rainy period. The abnormal chlorophyll-a concentration was mainly driven by meteorological factors such as typhoon and rainfall in the coastal areas of Jeju and the North Marine Areas of East China Sea. The abnormal high chlorophyll-a concentration at the majority of the coastal stations indicate eutrophication of coastal waters, especially Red tide. The events such as eutrophication and abnormal high chlorophyll-a concentration may potentially influence outbreak of Red Tide, detected with GOCI parameters.

• Journal of Microbiology and Biotechnology
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• 제22권8호
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• pp.1148-1154
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• 2012

A novel two-phase anaerobic treatment technology was developed to treat high-concentration organic cassava bioethanol wastewater. The start-up process and contribution of organics (COD, total nitrogen, and $NH_4^+$-N) removal in spatial succession of the whole process and spatial microbial diversity changing when sampling were analyzed. The results of the start-up phase showed that the organic loading rate could reach up to $10kg\;COD/m^3d$, with the COD removal rate remaining over 90% after 25 days. The sample results indicated that the contribution of COD removal in the pre-anaerobic and anaerobic phases was 40% and 60%, respectively, with the highest efficiency of 98.5%; TN and $NH_4^+$-N had decreased to 0.05 g/l and 0.90 g/l, respectively, and the mineralization rate of total nitrogen was 94.8%, 76.56% of which was attributed to the anaerobic part. The microbial diversity changed remarkably among different sample points depending on the physiological characteristics of identified strains. Moraxellaceae, Planococcaceae, and Prevotellaceae were dominant in the pre-anaerobic phase and Bacteroidetes, Campylobacterales, Acinetobacter, Lactobacillus, Clostridium, and Bacillus for the anaerobic phase. Methanosarcinaceae and Methanosaeta were the two main phylotypes in the anaerobic reactor.

• 한국환경과학회지
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• 제13권4호
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• pp.377-387
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• 2004

This study has been performed to clarify the characteristics of temporal and spatial distribution of surface ozone concentration over Jeju Island, one of the cleanest areas in Korea with low emissions of air pollutants. Ozone data are monitored at four sites in Jeju Island. These monitoring sites are located at two urban area(referred to Ido and Donghong), coastal area(Gosan site) and forest site(Chuna site). Ozone data has been routinely collected at these sites for the late four years. The patterns of seasonal cycle of ozone concentrations at all stations show the bimodal with the peaks on spring and autumn and a significant summer minimum. However, the patterns of diurnal variations at rural station, i.e., Gosan and Chuna sites are considerably different to those at urban stations such as Ido and Donghong sites. The patterns of $\DeltaO_3$ variations are very similar with those of monthly mean ozone concentrations and $\DeltaO_3$ values are exceeded 30 ppb, at urban stations. This may be that urban stations are more influenced by local photochemical reactions rather than rural stations. In order to assess the potential roles of meteorological parameters on ozone formation, the meteorological parameters, such as radiation, temperature, and wind are monitored together with ozone concentrations at all stations. The relationships of meteorological parameters to the corresponding ozone concentration are found to be insignificant in Jeju Island. However, at Gosan and Donghong stations, when the sea breeze blew toward the station, the ozone concentration is considerably increased.