• Journal of environmental and Sanitary engineering
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• v.18 no.1
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• pp.51-57
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• 2003

Indoor air quality(IAQ) in workplace and residential environments has been concern of people. Recently, Ministry of Environment in Korea has recognized the potential risk on the healthy effect related to indoor air pollution at home. Therefore, the purpose of this study was performed to measure the indoor air pollutants of IAQ at different homes and investigate to compare the perception of IAQ recognition at home from questionnaire survey in Seoul. We estimated the IAQ of selected 6 homes based on site region and housing type. The indoor air pollutants and parameters such as temperature, relative humidity, respirable suspended particulate matter($PM_{10}$), formaldehyde(HCHO), total bacteria counts, carbon monooxide(CO) and carbon dioxide($CO_2$) were monitored for summer and winter. In monitoring results, the respirable suspended particulate matter(($PM_{10}$) and indoor airborne bacteria level of home 5 and 6 were higher than the standard of the public $150{\;}{\mu}g/m^3$ and $500{\;}{\mu}g/m^3$, the level formaldehyde(HCHO) was exceed 0.1 ppm of the standard of Korea at all monitored homes. In statistics analysis, we could find a correlation between the building age and the concentration of CO, TBC were significant at 0.01 level and Relative Humidity was significant at 0.05 level for summer. Finally, the important air pollutants of IAQ in home were HCHO and total bacteria counts(TBC). And we performed a questionnaire survey of 500 people about their awareness for the importance of IAQ in our home during same period. In results, all most response of occupant has recognized the importance of IAQ at home. Therefore, it can be concluded that the IAQ of selected 6 home studied was perceived as acceptable, it is recommended that the government related IAQ was suggested the guideline and control of IAQ problems, and the occupants need to be effort to reduce the exposure of sources to undesirable pollutants.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.1
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• pp.38-55
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• 2018

Hourly measurements of $PM_{2.5}$ mass, organic and elemental carbon (OC and EC), and water-soluble ionic species were made at the air quality intensive monitoring stations in Baengryeongdo (BR) and Seoul (SL) during the winter (December 01~31, 2013) and summer (July 10~23, 2014) periods, to investigate the increase of $PM_{2.5}$ and secondary ionic species and the reasons leading to their increase during the two seasons. During winter, $PM_{2.5}$ and its major chemical species concentrations were higher at SL than at BR. Contribution of organic mass to $PM_{2.5}$ was approximately 1.7 times higher at BR than at SL, but the $NO_3{^-}$ contribution was two times higher at SL. Total concentration of secondary ionic species ($SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$) at BR and SL sites accounted for 29.1 and 40.1% of $PM_{2.5}$, respectively. However, during summer, no significant difference in chemical composition of $PM_{2.5}$ was found between the two sites with the exception of $SO{_4}^{2-}$. Total concentration of the secondary ionic species constituted on average 43.9% of $PM_{2.5}$ at BR and 53.0% at SL. A noticeable difference in chemical composition between the two sites during summer was attributed to $SO{_4}^{2-}$, with approximately twofold concentration and 10% higher contribution in SL. Low wind speed and high relative humidity were important factors in secondary formation of water-soluble ionic species during winter at SL, resulting in $PM_{2.5}$ increase. While the secondary formation during summer was attributed to strong photochemical processes in daytime and high relative humidity in nighttime hours. The increase of $PM_{2.5}$ and its secondary ionic species during the winter haze pollution period at SL was mainly caused either by long-range transport (LTP) from the eastern Chinese regions, or by local pollution. However, the increased $SO{_4}^{2-}$ and $NO_3{^-}$ during summer at SL were mainly caused by LTP, photochemical processes in daytime hours, and heterogeneous processes in nighttime hours.

• Journal of Food Hygiene and Safety
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• v.32 no.4
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• pp.321-328
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• 2017

Fusarium graminearum is a mycotoxigenic plant pathogen, which could remain in harvested barley grains and produces mycotoxins at preferable conditions during storage. To elucidate the factors affecting contamination of Fusarium and Fusariotoxin in hulled barley during storage, three hulled barley grain samples were collected from Jeolla province. Moisture content of each sample was adjusted to 14% and 20%, respectively, then stored in two warehouses where temperature was controlled differently: one controlled below $12^{\circ}C$, and the other with no control. While monitoring temperature and relative humidity of warehouses hourly, grain moisture content, Fusarium occurrence, and mycotoxin level was analyzed at 1, 3, 6, and 12 month after storage. The average monthly temperature and relative humidity ranged $3{\sim}29^{\circ}C$, and 58~70% in warehouse without temperature control, whereas $3{\sim}13^{\circ}C$ and 62~74% in warehouse controlled below $12^{\circ}C$. Grain moisture content of the samples decreased in both warehouses except 14% samples which increased in the warehouse with temperature control. Fusarium frequency of the contaminated grains decreased continuously in the warehouse without temperature control. But in the warehouse below $12^{\circ}C$, Fusarium decreasing rate was slower because of high grain moisture content. In most samples, nivalenol was detected more in the warehouse without temperature control after 12 month but there was little difference after 1, 3, and 6 month. Therefore, it will be efficient to store hulled barley in the warehouse controlled below $12^{\circ}C$ to reduce Fusarium contamination when the barley is not dried properly. In addition, when storage period exceeds 12 month, it is recommended to store hulled barley in a warehouse controlled below $12^{\circ}C$ to reduce nivalenol contamination.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.2
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• pp.132-142
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• 2010

Characteristics of meteorological elements were analyzed at Hwagae and Agyang where are the representative areas of Hadong green tea cultivation in Korea. An automatic weather monitoring system (AWS) and a simple data log were employed to measure meteorological data such as temperature, relative humidity, precipitation, and wind direction and speed for 2009. The annual average air temperature of Hwagae and Agyang was 14.5 and 14.2, respectively, showing the warmest month in August ($25.4^{\circ}C$ for Hwagae and $24.9^{\circ}C$ for Agyang) and the coldest month in January ($0.3^{\circ}C$ for Hwagae and $0.2^{\circ}C$ for Agyang). Annual average of daily temperature difference (= daily maximum temperature - daily minimum temperature) was $11.3^{\circ}C$ for Hwagae and $11.1^{\circ}C$ for Agyang. Hwagae and Agyang had 62.7% and 65.3% of the annual average relative humidity, respectively. Annual precipitation was 1387 mm for Hwagae and 1793 mm for Agyang of which were higher of 605mm for Hwagae and 835 mm for Agyang compared to that in 2008. Majority of precipitation occurred between May and August, attributing 77.6% for Hwagae and 76.6% for Agyang to the annual precipitation. The annual total sunshine duration was 2054.3 hrs in Hwagae with the longest monthly sunshine duration in May (235.1 hrs) and the shortest monthly sunshine duration in July (102.5 hrs). Dominant wind direction changed seasonally from northwesterly wind in fall and winter to southeasterly wind in spring and summer. The annual average wind speed was 1.5 m $s^{-1}$ with the highest monthly wind speed of 2.0 m $s^{-1}$ in December and the lowest monthly wind speed of 1.1 m $s^{-1}$ in February. It is expected that continuous observation and assessment of meteorological data will improve our understanding of optimal environmental conditions for green tea cultivation and be used for developing models of green tea cultivation in the Hadong area.

• Korean Journal of Environment and Ecology
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• v.31 no.4
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• pp.397-408
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• 2017

The purpose of this study is to identify the home range and habitat using pattern of the native species, Mauremys reevesii, and the exotic species, Trachemys scripta elegans, and to analyze the mutual competition relationship of the two species. This study was conducted at the Goldfish square pond, which is located in the upper part of the valley of Cheonggye mountain from August 2, 2010 to January 30, 2011. We used the three artificially proliferating M. reevesii and three T. scripta elegans which were inhabited in the ponds and reservoirs for monitoring study after attaching the transmitter to each of them. We measured the home range and the habitat utilization radius of three individuals of each species and the environmental factors such as temperature, humidity and soil and water temperature around the Goldfish square pond. As our results, it was analyzed that the M. reevesii and T. scripta elegans have a redundant ecological positions in various aspects such as limited sunbathing places, food resource utilization, hibernation place, etc. We also found that the relatively small M. reevesii was being pushed out of the competition by the relatively big. Further investigation of food competition and habitat utilization should be necessary for these two species for the natural habitats, their home range, food competition, and habitat utilization. The result of this study will be the basic data M. reevesii's restoration project.

• Particle and aerosol research
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• v.13 no.3
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• pp.105-110
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• 2017

Real-time measurements of fine particles from stack emission gases are necessary due to the needs of continuous environmental monitoring of PM10 and PM2.5. The porous tube dilutor using hot and cold dilutions was developed to measure fine particles without condensable particles from highly humid emission gases and compared to the commercialized ejector-type dilutor. Particle size distributions were measured at the emission gases from a diesel engine and a coal-fired boiler. The porous tube dilutor could successfully measure the accumulation mode particles including relatively large particles more than $3{\mu}m$ without nuclei particles, while the ejector dilutor detected some condensable particles and could not detect large particles. The porous tube dilutor could successfully remove the already condensed water droplet particles generated by a humidifier in a $30m^3$ chamber.

• Journal of the Korean Wood Science and Technology
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• v.48 no.6
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• pp.917-935
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• 2020

In this study, an automated sensor to measure forest fire surface fuel moistures was developed to predict changes in the moisture content and risk of forest fire surface fuel, which was indicators of forest fire occurrence and spread risk. This measurement sensor was a method of automatically calculating the moisture content of forest fire surface fuel by electric resistance. The proxy of forest fire surface fuel used in this sensor is pine (50 cm long, 1.5 cm in diameter), and the relationship between moisture content and electrical resistance, R(R:Electrical resistance)=2E(E:Exponent of 10)+13X(X:Moisture content)-9.705(R²=0.947) was developed. In addition, using this, the software and case of the automated measurement sensor for forest fire surface fuel moisture were designed to produce a prototype, and the suitability (R²=0.824) was confirmed by performing field monitoring verification in the forest. The results of this study would contribute to develop technologies that can predict the occurrence, spread and intensity of forest fires, and are expected to be used as basic data for advanced forest fire risk forecasting technologies.

• The Journal of the Korea Contents Association
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• v.17 no.2
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• pp.327-336
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• 2017

People spend most of their time in the indoor environment. Among the various indoor environmental factors, air and thermal environment directly affect human's health and efficiency of work. Therefore, efficient monitoring of indoor environment is highly important. For assisting the residents to understand the state of the indoor environment much easier and more intuitive, this paper analyze the visualization cases of the conventional indoor environment. Then explore the direction of improvement for the visualization method to propose a more effective visualization method. The approach of web and BIM(Building Information Model)-based visualization of indoor environment proposed in this study is composed of four major parts: 1) the generation of the model data of the building; 2) the generation of indoor environmental data; 3) the creation of visualization elements; 4) data mapping. Then it realized through the generating process of visualization results.

• Journal of Conservation Science
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• v.18 s.18
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• pp.19-32
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• 2006

The stone pagoda of the Bunhwangsa temple made by piling small brick-shaped stones. The major rock forming stone bricks are andesites with variable genesis. Rock properties of the pagoda roof stone suffer partly including multiple peel-offs, exfoliation, decomposition like onion peels, cracks forming round lines and falling off stone pieces. The stylobates and tabernacles in all the four directions the pagoda are mostly composed of granitic rocks. Those rock properties are heavily contaminated by lichens and mosses with the often marks of inorganic contamination by secondary hydrates that are dark black or yellowish brown. Within the four tabernacles and northern pagoda body situated to relatively high humidity. There are even light gray precipitate looking like stalactites between the northern and western rocks of the body Their major minerals are calcite, gypsum and clays. The stone lion standing in the southeast and northeast side are alkali granite, while that in the southwest and northwest lithic tuff. Total rock properties of the pagoda are 9,708 pieces, among the all properties, fractured blocks are 11.0%, fall out blocks are 6.7% and covered blocks by precipitates are 7.0%, respectively. The pagoda has highly deteriorated the functions of the rock properties due to physical, chemical and biological weathering, therefore, we suggest that this pagoda has need to do long term monitoring and synthetic conservation researches.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.411-418
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• 1996

This experiment was conducted to investigate the effect of electric conductivity (EC) and potassium (K) concentration level in the culture solution on the growth and the air pollution monitoring capability of Perilla frutescens Suwon 16 which was recognized as a possible bioindicator for air pollution. The plants were exposed to $NO_2$, $O_3$, $SO_2$ and $NO_2+SO_2$ within a phytotron at $25^{\circ}C$ (day) or at $20^{\circ}C$(night) with 70% of relative humidity and evaluated the effect of EC and K level on the injury of the plants, The highest dry weights were gained as 16.3 g/plant at 0.5 dS/m of EC and as 32.3 g/plant at 100 and 200mg/l of K concentration, respectively. The diffusive resistances appeared as low values at 0.5 dS/m of EC and at 50, 100mg/l of K concentration. The increasing of the visible injury with increasing the dose of air pollutants could be taken at 0.5. 1.0 ds/m of EC and at 50, 100mg/l of K. The recommendable level of EC and K of the culture solution were 0.5-1.0 dS/m of electric conductivity. 50-100mg/l of K for the plant as an air pollutant biomonitor, when the 7th or 8th leaf was developed.