• Journal of Aerospace System Engineering
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• v.6 no.3
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• pp.1-6
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• 2012

It is booming to use computer owing to the information society, and embedded software application have grown in airborne systems and equipment. So this introduces airborne software, RTCA DO-178B, life cycle and its data, and software development pitfalls in design and certification.

• Journal of environmental and Sanitary engineering
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• v.10 no.2
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• pp.67-73
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• 1995

In order to study of characteristics of collected filter as analysis of carbon in airborne particulate matters by Elemental Analyzer, quartz fiber filter and glass fiber filter were used. The results are followed as; There was no difference of confidence in collection rate of airborne particulate matters between quartz fiber filter and glass fiber filter. Airborne particulate matters were collected on both filters evenly and the use of quartz fiber filter is better than glass fiber filter as analysis of carbon by thermal method.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.1
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• pp.43-52
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• 2007

This study was designed to investigate the difference of airborne lead concentration by type of lead industries and type of lead exposure and to evaluate their association with lead biomarkers of lead workers in 11 lead using industries. Total of 182 lead workers (male: 167, female: 15) from 11 lead industries were participated for this study from March, 2004 to August, 2005. Airborne lead concentration were measured by representative personal sampling of workers in each unit workplace and applied same concentration value to the workers in the same unit workplace who did not measure their airborne lead with personal air sampling. Tibia lead, blood lead, zinc protoporphyrin in whole blood, ${\delta}$-aminolevulinic acid in urine, hemoglobin and hematocrit were selected as study variables of indices of lead exposure. Information about type of lead exposure (fume or non-fume other), age, work duration, smoking & drinking habit were also collected. Significant differences were seen in the means of zinc protoporphyrin, blood lead and tibia lead in lead workers by different airborne lead concentration in workplace. While blood lead and tibia lead in lead workers were significantly higher in secondary smelting than other types of lead industries, zinc protoporphyrin, ${\delta}$-aminolevulinic acid in urine and airborne lead concentration were significantly higher in litharge manufacturing. While the mean blood lead was significantly higher in the lead workers working in fume type unit workplace than those of non-fume lead workers, the mean airborne lead concentration of fume workers was significantly lower than non-fume lead workers. In the multiple regression analysis of airborne lead concentration and the type of lead exposure on tibia lead and lead exposure indices after adjustment of related covariates, airborne lead concentration was statistically significantly associated with blood lead and tibia lead, but the type of lead exposure was only associated with blood lead. To verify the causal association of airborne lead concentration on blood lead and tibia lead, further studies are needed.

• Journal of Environmental Health Sciences
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• v.32 no.1 s.88
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• pp.36-45
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• 2006

The aim of this study is to examine size-based concentration and genera of airborne fungi distributed in public facilities such as hospital, kindergarten, day-care center and postpartum nurse center and to provide fundamental data in order to prevent respiratory diseases caused by exposure to airborne fungi. Culturable total and respirable concentrations of airborne fungi averaged to $382\;cfu/m^3\;and\;292\;cfu/m^3$ in hospital, $536\;cfu/m^3\;and\;347\;cfu/m^3$ in kindergarten, $334\;cfu/m^3\;and\;266\;cfu/m^3$ in day-care center, and $371\;cfu/m^3\;and\;289\;cfu/m^3$ in postpartum nurse center, respectively. The ratio of respirable to total concentration of airborne fungi in the investigated public facilities was ranged from $55\%\;to\;70\%$ but there was no significant difference among them (p>0.05). The mean I/O ratio of culturable total and respirable concentrations were 0.56 and 0.64 in hospital, 0.72 and 0.91 in kindergarten, 0.33 and 0.45 in day-care center, and 0.63 and 0.73 in postpartum nurse center, respectively. Indoor concentration of airborne fungi did not correlated significantly with indoor temperature and relative humidity (p>0.05) but had a significant positive correlation with $CO_2$ concentration (p<0.01) and surrounding condition (p<0.05). Penicillium spp., Cladosporium spp., and Aspergillus spp. were estimated to over $95\%$ of total airborne fungi identified in the investigated public facilities.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.4
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• pp.356-363
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• 2006

To investigate the exposure effect of benzene, we measured airborne benzene as external doses, uninary tt-muconic acid as an internal dose of benzene exposure and analyzed the relationship between tt-muconic acid concentration and benzene exposure. The study population of eight businesses included 157 workers(87 workers in field; exposure group, 70 workers in board; control group) who produce or use benzene in petrochemical industry. The concentrations of airborne benzene were evaluated by personal samples and urine was sampled at the pre and end shift. Urinary t,t-muconic acid as internal dose was to analyze the relationship with airborne benzene. The geometric means(GM) of airborne benzene was 0.0231 ppm(range ND-1.0471 ppm) in exposure group and 0.0147 ppm(range ND-0.3162 ppm) in control group. The geometric means(GM) of urinary t,t-muconic acid at end-shift was $196.8{\pm}2.23{\mu}g/g$ creatinine in exposure group and $149.2{\pm}2.08{\mu}g/g$ creatinine in control group. There was significant correlation between the airborne concentration of benzene and the urinary concentration of t,t-muconic acid( r=0.711, p<0.01). From the results of stepwise multiple regression analysis about t,t-muconic acid at end-shift, significant independents was airborne benzene. In this study, there were significant correlation between the urinary concentration of t,t-muconic acid and the airborne concentration of benzene. More extensive studies ruling out healthy worker effect is needed.

• The Plant Pathology Journal
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• v.35 no.6
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• pp.585-597
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• 2019

A disease forecast model for Marssonina blotch of apple was developed based on field observations on airborne spore catches, weather conditions, and disease incidence in 2013 and 2015. The model consisted of the airborne spore model (ASM) and the daily infection rate model (IRM). It was found that more than 80% of airborne spore catches for the experiment period was made during the spore liberation period (SLP), which is the period of days of a rain event plus the following 2 days. Of 13 rain-related weather variables, number of rainy days with rainfall ≥ 0.5 mm per day (L_day), maximum hourly rainfall (P_max) and average daily maximum wind speed (W_avg) during a rain event were most appropriate in describing variations in airborne spore catches during SLP (S_i) in 2013. The ASM, Ŝ_i = 30.280+5.860×L_day×P_max-2.123×L_day×P_max×W_avg was statistically significant and capable of predicting the amount of airborne spore catches during SLP in 2015. Assuming that airborne conidia liberated during SLP cause leaf infections resulting in symptom appearance after 21 days of incubation period, there was highly significant correlation between the estimated amount of airborne spore catches (Ŝ_i) and the daily infection rate (R_i). The IRM, ${\hat{R}}_i$ = 0.039+0.041×Ŝ_i, was statistically significant but was not able to predict the daily infection rate in 2015. No weather variables showed statistical significance in explaining variations of the daily infection rate in 2013.

• Journal of Environmental Health Sciences
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• v.28 no.2
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• pp.109-116
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• 2002

The purpose of this study was to evaluate a new sampling and analytical method for the determination of airborne hexavalent chromium, Cr(Ⅵ), in a field plating operation. The procedures of this new method (Shin & Paik's Method) are as the following: Airborne hexavalent chromium is collected on polyvinyl chloride (PVC) filter according to the National Institute iota Occupational Safety and Health (NIOSH) Method 7600, and the filler sample is placed in a screw-capped vial and soaked with 2% NaOH/3% Na₂CO₃ solution immediately after sampling. The Cr(Ⅵ) sample is analyzed by ion chromatography/visible spectrophotometry (IC/VS) according to the U.S. Environmental Protection Agency (EPA) Method 218.6. The airborne Cr(Ⅵ) concentrations measured by this method were compared with those determined by three reference methods: One (NIOSH/EPA Method) consisted of sampling airborne Cr(Ⅵ) on PVC filters and storing the sample filters in strew-capped vials according to the NIOSH method, and analyzing Cr(Ⅵ) in samples using IC/VS according to the EPA method. The second method (Impinger Method/NaHCO₃) consisted of absorbing airborne Cr(Ⅵ) into 0.02 M NaHCO₃ solution in midget impinger, and analyzing the Cr(Ⅵ) in samples using IC/VS. The third method was the OSHA Method ID-215. Using these four different methods, lour replicates of air samples were collected at an electroplating process and analyzed simultaneously. Two-way ANOVA and paired t-test were used to test difference among values determined by the methods. There was no significant difference and a strong correlation (r²:0.99) between Cr(Ⅵ) concentrations measured by the Shin & Paik's Method and an impinger method (p>0.05). However, Cr(Ⅵ) concentrations determined by Shin & Paik's Method were significant1y different from those by the NIOSH/EPA Method (p<0.05) or the OSHA method (p<0.05). The Cr(Ⅵ) concentrations of Shin & Paik's Method were significantly higher than those of the NIOSH/EPA Method or the OSHA method. This result indicated that the Shin & Paik's Method may prevent Cr(Ⅵ) losses caused by reduction and give more reliable results of airborne Cr(Ⅵ) concentrations in work environments.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.4
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• pp.693-699
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• 2006

Digital airborne image must be precisely orthorectified to become geographical information. For orthorectification of airborne images, GPS/INS (Global Positioning System/Inertial Navigation System) and LIDAR (LIght Detection And Ranging) elevation data were employed. In this study, 635 frame airborne images were produced and LIDAR data were converted to raster image for applying to image orthorectification. To derive images with constant brightness, flat field correction was applied to images. The airborne images were geometrically corrected by calculating internal orientation and external orientation using GPS/INS data and then orthorectified using LIDAR digital elevation model image. The precision of orthorectified images was validated by collecting 50 ground control points from arbitrary five images and LIDAR intensity image. As validation result, RMSE (Root Mean Square Error) was 0.387 as almost same as only two times of pixel spatial resolution. It is possible that this automatic orthorectification method of airborne image with higher precision is applied to airborne image industry.

• Journal of Environmental Health Sciences
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• v.18 no.1
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• pp.12-21
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• 1992

This study was performed to determine the concentrations of airborne TSP, Pb and street dust Pb in Kuro, Chongro, Namsan Tollgate and kwachun from August 15 to September 15, 1990.The results of this study are as follows. 1. Average airborne TSP concentrations in chongro and Kuro were 460$\mu$g/m$^{3}$ and 440$\mu$g/m$^}3}$, respectively, and exceeded the Korean air quality standards of 300$\mu$g/m$^{3}$. Average airborne TSP concentrations in Namsan Tollgate and Kwachun were 270$\mu$g/m$^{3}$ and 80$\mu$g/m$^{3}$, respectively, and didn't exceeded the Korean air quality standards of 300$\mu$g/m$^{3}$. The airborne TSP concentrations between Seoul area(Kuro, Chongro and Namsan Tollgate) and Kwachun area were significantly different (p < 0.01). 2. Average airborne Pb concentrations in Chongro, Kuro, Namsan Tollgate and Kwachun were 1.07, 0.55, 0.84 and 0.16$\mu$g/m$^{3}$, respectively. All the airborne Pb concentration at four area were below the Korean air quality standards of 1.5$\mu$g/m$^{3}$. The airborne Pb concentrations between Seoul area (Kuro, Chongro and Narnsan Tollgate) and Kwachun area were significantly different (p < 0.01). 3. Pb contents in street dusts in Kuro, Chongro, Namsan Tollgate and Kwachun were 9.30, 15.25, 18.17 and 3.16$\mu$g/g, respectively. The Pb contents in street dusts between Seoul area(Kuro, Chongro and Namsan Tollgate) and Kwachun area were significantly different (p < 0.01). 4. The airborne TSP and Pb concentrations were highly correlated(r=0.68), but the Pb concentrations in street dusts and atmosphere were poorly correlated(r=0.22).

• Journal of Environmental Health Sciences
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• v.26 no.4
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• pp.21-28
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• 2000

Various man-made mineral fibers(MMMF) including refractory ceramic fiber(RCF) have been used widely in industries as insulation materials. The effect of fibrous dust on human health depends on fiber size, concentration (exposure level), and durability in biological system. Therefore, these parameters should be determined to evaluate accurately the potential risk of fibers on human health. The purpose of this study was to characterize the size of airborne fiber and the workers＇ exposure to airborne fibers in refractory ceramic fiber manufacturing and processing factories. Airborne fibers were collected on 25-mm mixed cellulose ester membrane filters at personal breathing zones, and analyzed by A and B counting rules of the National Institute for Occupational Safety and Health(NIOSH) Method # 7400. The average ratios of the fiber density by B rule to the fiber density by A rule was 0.84. This result indicates that the proportion of respirable fibers (<3 ${\mu}{\textrm}{m}$ diameter) in air samples was high. The average diameter and length of airborne fibers were 1.05${\mu}{\textrm}{m}$ and 35${\mu}{\textrm}{m}$, respectively. The average fiber concentrations (GM) of all personal samples was 0.26f/cc, and the average concentration was highest at blanket cutting and packing processes. The fifty seven percent of personal air samples was exceeded the proposed American Conference of Governmental Industrial Hygienists(ACGIH) Threshold Limit Value(TLV), i.e. 0.2 f/cc. It was concluded that the RCF industrial workers had the higher potential health risk due to small fiber diameter, long fiber length, and high exposure level to the airborne fibers.