• The Journal of the Korea Contents Association
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• v.15 no.8
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• pp.544-555
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• 2015

This study aims to derivate of the relationship and rating curve for the flow discharge-total sediment using the measured field data from the main points of small-medium stream reaches in agrarian basin. The total sediment of measured data are obtained by bed load added to suspended load which analyzed using the particle size distribution curve of sieve test and the dry or the filtration method from the collected samples by samplers (DH-48, D-74 and BLH-84, BL-84) at the stream bed and the depth-averaged concentration, respectively. These field data had been collected from August 2012 to September 2014 at the seven measuring stations of the national-local channel reaches of the four study streams in the Nonsan river systems of agrarian basin. As a result, the relationships and the rating curve for the flow discharge-total sediment are derived as a function pattern of power law by analyzing on a distribution characteristic of the database set and it will be used as a useful tool to analyze erosion, deposition, and transportation in theoretical research as well as in practical application of the hydraulic sedimentation engineering.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.3
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• pp.289-296
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• 1996

Effects of crustal species on the characteristics of ambient particles were studied by applying a gas-particle equilibrium model, SCAPE, to the measurements at Kosan, Cheju Island during the spring and summer, 1994. Two cases were simulated; the measured composition was used without any modification (case 1), and the metal ion concentrations originated from crust were subtracted from the measured particle composition (case 2). Total suspended particles (TSPs) were collected by an automatic high volume tape sampler during spring period and by high volume samplers during summer period. The fine particles, PM 2.5, and gaseous volatile species were collected using a filter pack smapler during summer period. The water soluble ion concentrations were analyzed from all the particle samples. According to the simulation results, the effect of crustal elements on the chemical composition of particles is negligible for both TSP particles and PM 2.5 particles. Acidity of particles measured at Kosan, however, is affected by the change of the concentrations of crustal species, stronger effects for TSP particles than for PM 2.5 particles during summer, and stronger effects during summer than spring for TSP particle. The average pH decrease due to the absence of crustal species was about 0.10 for PM 2.5 particle during summer and 1.51 and 0.85 for TSP particles during summer spring, respectively. Water contents of PM 2.5 particles for both cases are comparable to each other. Estimated water content of TSP particles for case 2 is higher than that for case 1 by about 4 $\sim 6 \mum/m^3$ because salts of metal ions are not hygroscopic.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.7
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• pp.777-784
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• 2005

The first flush phenomenon is defined as the initial period of road runoff during which the concentration of pollutants was significantly high. Road runoff contains significant loads of micro-particles, heavy metals and organic constituents. There were two major objectives of this study. The first objective was to characterize the road runoff. The second objective was to measure and evaluate particle sire distribution of the road runoff, Stormwater runoff was monitored on two sites of four lane road areas along with traffic volume. A total six storm events were monitored to characterize the road runoff. The quantity of road runoff and quality constituents, including chemical oxygen demand ($COD_{Cr}$), suspended solids(SS), total Kjeldahl nitrogen (TKN), ortho-phosphorus ($PO_4-P$), total phosphorus(TP), heavy metals and particle size distribution were analyzed. The results indicate that the concentration of SS, $COD_{Cr}$, TKN and TP ranges were $45{\sim}2,396\;mg/L$, $40{\sim}931\;mg/L$, $0.1{\sim}19.6\;mg/L$, and $0.2{\sim}25.1\;mg/L$, respectively. The results of the regression analysis between SS and the others constituents shows that $COD_{Cr}$, TP, Cu, Pb were highly correlated. And the results showed that the mean range of particle size and uniformity coefficient for road runoff were $6.7{\sim}23.4{\mu}$ and $6.4{\sim}10.2$, respectively.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.19-26
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• 2003

The dispersion of recycled particulates in the complex coastal terrain containing Kangnung city, Korea was investigated using a three-dimensional non-hydrostatic numerical model and lagrangian particle model (or random walk model). The results show that particulates at the surface of the city that float to the top of thermal internal boundary layer (TIBL) are then transported along the eastern slope of the mountains with the passage of sea breeze and nearly reach the top of the mountains. Those particulates then disperse eastward at this upper level over the coastal sea and finally spread out over the open sea. Total suspended particulate (TSP) concentration near the surface of Kangnung city is very low. At night, synoptic scale westerly winds intensify due to the combined effect of the synoptic scale wind and land breeze descending the eastern slope of the mountains toward the coast and further seaward. This increase in speed causes development of internal gravity waves and a hydraulic jump up to a height of about 1km above the surface over the city. Particulate matter near the top of the mountains also descends the eastern slope of the mountains during the day, reaching the central city area and merges near the surface inside the nocturnal surface inversion layer (NSIL) with a maximum ground level concentration of TSP occurring at 0300 LST. Some particulates were dispersed following the propagation area of internal gravity waves and others in the NSIL are transported eastward to the coastal sea surface, aided by the land breeze. The following morning, particulates dispersed over the coastal sea from the previous night, tend to return to the coastal city of Kangnung with the sea breeze, developing a recycling process and combine with emitted surface particulates during the morning. These processes result in much higher TSP concentration. In the late morning, those particulates float to the top of the TIBL by the intrusion of the sea breeze and the ground level TSP concentration in the city subsequently decreases.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.6
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• pp.715-727
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• 2004

This study was carried out to evaluate non-smoker's exposure levels to environmental tobacco smoke (ETS) in the air of offices in urban areas. A total of 65 offices were selected from two large cities, i.e. Daegu and Daejeon. The field sampling was conducted repeatedly in summer (1999) and winter (1999～2000). The measured ETS markers included respirable suspended particles (RSP as PM$_{40}$ ), vapor and particulate phase ETS markers, including nicotine, 3-ethnyl pyridine (3-EP), ultraviolet absorbing particulate matter (UVPM), fluorescing particulate matter (FPM), and solanseol in ETS particles (SolPM). RSP was measured gravimetrically by a microbalance. The particle samples were then used for the determination of particulate ETS markers by HPLC, while vapor phase markers determined by GC/NPD. The analytical methods were validated for repeatability, linearity, detection limits, and duplication precision. The concentrations of RSP and other ETS markers were significantly higher in smoking offices than non-smoking offices. Despite the similar smoking strength in each office for different seasons, the concentration levels of ETS components appeared to be higher in winter than summer. The contributions of ETS to RSP concentrations based on SolPM, FPM, and UVPM methods were estimated to be in the range of 15.2 ～ 25.3% in smoking offices, whereas 2.4 ～ 15.9% in non-smoking offices. The cooling and heating types did not affect significantly the concentrations of RSP and other ETS markers. Finally, further research issues were suggested to obtain more scientific information on the non-smoker's exposure to ETS with respect to the frame of risk assessment..

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.1
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• pp.51-63
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• 1997

Total suspended particulate matters in the ambient air were analyzed for eight chemical elements (Ca, Co, Cu, Fe, Mn, Pb, Si, and Zn) using an x-ray fluorescence spectrometry (XRF) at the Kyung Hee University - Suwon Campus during 1989 to 1994. To use these data as basis for source identification study, membership of each sample was selected to represent one of the well defined sample groups. The data sets consisting of 83 objects and 8 variables were initially separated into two groups, fine (d$_{p}$<3.3 ${\mu}{\textrm}{m}$) and coarse particle groups (d$_{p}$>3.3 ${\mu}{\textrm}{m}$). A hierarchical clustering method was examined to obtain possible member of homogeneous sample classes for each of the two groups by transforming raw data and by applying various distances. A disjoint principal component analysis was then used to define homogeneous sample classes after deleting outliers. Each of five homogeneous sample classes was determined for the fine and the coarse particle group, respectively. The data were properly classified via an application of logarithmic transformation and Euclidean distance concept. After determining homogeneous classes, correlation coefficients among eight chemical variables within all the homogeneous classes for calculated and meteorological variables (temperature. relative humidity, wind speed, wind direction, and precipitation) were examined as well to intensively interpret environmental factors influencing the characteristics of each class for each group. According to our analysis, we found that each class had its own distinct seasonal pattern that was affected most sensitively by wind direction.ion.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.12
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• pp.1353-1359
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• 2007

Water quality constituents, and particle size distributions were characterized in urban bridge road runoff, Bridge road runoff contains significant loads of micro-particles, heavy metals and organic constituents. Bridge road runoff was monitored on four sites of four and six lanes bridge road areas along with traffic volume. A total seven storm events were monitored to characterize the bridge road runoff. The quantity of road runoff and quality constituents, including chemical oxygen demand(COD), suspended solids(SS), total nitrogen(T-N), ortho-phosphorus$(PO_4-P)$, total phosphorus(T-P), and particle size distribution were analyzed. The results indicate that the concentrations of SS, COD, T-N and T-P ranges were $35\sim2,390$ mg/L, $40\sim1,274$ mg/L, $0.03\sim21.25$ mg/L, and $0.05\sim4.58$ mg/L, respectively. And the results showed that the mean range of particle size and $D_{90}$ for bridge road runoff were $4.75\sim14.05{\mu}m$ and $17.33\sim58.15{\mu}m$, respectively.

• Journal of the Korean Society of Tobacco Science
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• v.21 no.1
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• pp.102-108
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• 1999

This study was conducted to evaluate the ventilation to remove gases, vapor and particles of environmental tobacco smoke(ETS) in a closed room. The ventilation rate choosed were 0.445 ㎥/min, 0.528 ㎥/min, and 0.625 ㎥/min. ETS components measured were total suspended particle(TSP), ultraviolet particulate matter(UVPM), fluorescent particulate matter(FPM), solanesol, carbon dioxide($CO_2$), carbon monoxide(CO), nicotine, and 3-ethenylpyri-dine(3-EP). The concentration of ETS components measured rapidly decreased as increasing ventilation rate, but the removal efficiency by ventilation was different from each ETS compounds. The $CO_2$, and CO, gaseous components of ETS, were dominant components to be removed from the room by ventilation. The ventilation with 0.528 ㎥/min for 1 hr was enough to remove over 99% of those gaseous components. Nicotine and 3-EP needed the ventilation for 2 hrs to reduce over 95 % of those components. As the same ventilation rate, 99 % of TSP and solanesol concentration were removed from the room within 2 hrs, UVPM and FPM concentration decreased 90 %.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.4
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• pp.285-296
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• 1997

The suspended particulate matters had been collected on quartz fiber fiters by a cascade impactor having 9 size stages for 4 years (Sep. 1991 to Dec. 1995) in Kyung Hee University-Suwon Campus. Membrane filters were used to collected the particulate matters on each stage. The weight concentration on each stage was obtained by a microbalance and further chemical element levels were determined by an x-ray fluorescence system. Based on these chemical information, our study focused on applying the target transformation factor analysis (TTFA), a receptor model, to identify aerosol sources and to apportion quantitatively their mass contribution. There are total of 63 ambient data sets. Each data set consists of the 8 size-ranged subdata sets characterized by 16 elemental variables. By the results, four to five sources were extracted from each size range and some sources reappeared in other size ranges. Then total of 8 source profiles were statistically generated from all the ranges, such as oil burning source, soil source, field burning source, gasoline related source, coal burning source, marine source, glass related source, and unknown sources. Apportioning aerosol mass to each source was intensively examined by investigating emission inventories near the study area. The results showed that soil particle source was the most significant contributor. However, coal and oil burning sources were the major anthropogenic ones. The study finally proposed some air quality control strategies to achieve the clean air quality in Suwon area.

• Particle and aerosol research
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• v.17 no.4
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• pp.115-123
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• 2021

The emission gas from meat grilled restaurants has unpleasant odor and sticky particulate matters (PM) in form of oil mist. This affects the residents living nearby. In oder to decrease the odor and PM, electrostatic precipitators (ESP) were installed at several restaurants by support of Seoul metropolitan government and emission characteristics of PM and odor were investigated. The removal efficiency of odor and PM at before- and after-ESP was that total hydrocarbon (THC), NH₃, H₂S, acetaldehyde, butyraldehyde were not much decreased. Total suspended particles (TSP) emitted from the vent was below the value of 7 mg/m³ regardless of the concentration of before-ESP and removal efficiency was in the range of 64 ~ 86%. The ratio of PM_1.0 to PM₁₀ of emission gas was over 0.9. So it was revealed that most PM of emission gas was PM1.0. The PM concentration in the air of the street near the vent was higher than another street due to the emission gas and the PM of indoor air of restaurant grilling meats was measured very high compared to outdoor air. So it needs more powerful ventilation of indoor air.