• Journal of Korean Society for Atmospheric Environment
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• v.28 no.6
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• pp.697-705
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• 2012

Particulate matter (PM) data collected from the Urban Air Monitoring Network in Busan during the period from 2006 through 2010 were statistically examined and analyzed to estimate the probability of exceeding $PM_{2.5}$ 24 hour and annual standard to be implemented from January $1^{st}$, 2015. For Jangrimdong, Yeonsandong, Kijangeup, and Jwadong where simultaneous measurement of $PM_{10}$ and $PM_{2.5}$ was conducted, the probability of exceeding $PM_{2.5}$ standards was estimated using $PM_{2.5}$ data measured on site. For other areas where there were no measured $PM_{2.5}$ data available, the probability of exceeding $PM_{2.5}$ standards was statistically estimated using $PM_{10}$ measured on site and $PM_{2.5}/PM_{10}$ ratios obtained from the four stations where both $PM_{2.5}$ and $PM_{10}$ were monitored simultaneously. At Jangrimdong, Yeonsandong, Kijangeup, and Jwadong, mean value of annual 99 percentile of 24 hr average $PM_{2.5}$ for 5 years from 2006 through 2010 was 99.3, 74.5. 57.0, and $62.5{\mu}g/m^3$, respectively, and the probability of exceeding $PM_{2.5}$ 24 hr standard was estimated at 100%. For areas where there were no measured $PM_{2.5}$ data available, the estimated probability of exceeding $PM_{2.5}$ 24 hr standard was more than 0.82. Mean value of annual average $PM_{2.5}$ from 2008 through 2010 was 31.7 and $27.6{\mu}g/m^3$ for Jangrimdong and Yeonsandong, respectively, which exceeded $PM_{2.5}$ annual standard of $25{\mu}g/m^3$. Mean value of annual average $PM_{2.5}$ during the same period for Kijangeup and Jwadong was 19.2 and $20.7{\mu}g/m^3$, respectively, which satisfied $PM_{2.5}$ annual standard. For other areas where there were no measured $PM_{2.5}$ data available, the probability of exceeding $PM_{2.5}$ annual standard was more than 0.95 except Taejongdae and Kwangahndong. With $PM_{10}$ and $PM_{2.5}$ data measured at 17 Urban Air Monitoring Stations in Busan, the probability of exceeding $PM_{2.5}$ standards was estimated to be very high for almost all areas. This result indicates that proper measures to mitigate $PM_{2.5}$ in Busan should be investigated and established as soon as possible.

• Journal of the Korean Society of Safety
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• v.34 no.5
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• pp.144-152
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• 2019

According to the National Police Agency, point-to-point speed enforcement system is being installed and operated in 97 sections across the country. It is more effective than other enforcement systems in terms of stabilizing the traffic flow and inhibiting the kangaroo effect. But it is only 5.1% of the total enforcement systems. The National Police Agency is also aware that its operation ratio is very low and it is necessary to expand point-to-point speed enforcement system. Hence, this study aims to provide the expansion basis of the point-to-point speed enforcement operation through analysis of the quantitative effects and development the accident prediction model. Firstly, this study analyzed the effectiveness of point-to-point speed enforcement system. Naive before-after study and comparison group method(C-G Method) were used as methodologies of analyzing the effectiveness. The result of using the naive before-after study was significant. Total accidents, EPDOs and casualty crashes decreased by 42.15%, 70.64% and 45.30% respectively. And average speed and the ratio of exceeding speed limit decreased by 6.92% and 20.50%p respectively. Moreover, using the C-G method total accidents, EPDOs and casualty crashes decreased by 31.35%, 66.62% and 10.04% respectively. And average speed and the ratio of exceeding speed limit decreased by 3.49% and 56.65%p respectively. Secondly, this study developed a prediction model for the probability of casualty crash. It was dependant on factors of traffic volume, ratio of exceeding speed limit, ratio of heavy vehicle, ratio of curve section, and presence of point-to-point speed enforcement. Finally, this study selected the most danger sections to the major highway and evaluated proper installation sections to the recent installation section by applying the accident prediction model. The results of this study are expected to be useful in establishing the installation standards for the point-to-point speed enforcement system.

• YAKHAK HOEJI
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• v.53 no.5
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• pp.274-280
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• 2009

To survey the status of quality control of major ingredients of 'Ssanghwatang (Oriental medicine used for fatigue)', we analyzed 1,024 samples (9 kinds) of medical herbs to determine amounts of ashes, acid-insoluble ashes, loss on drying that are major elements to ensure basic quality of herbal drugstuffs. After ash analysis, Paeoniae Radix (from China) failed to meet the herbal standard criterion. After yielding Z-score(indicating the probability of exceeding its criterion) Zizyphi Fructus, Zingiberis Rhizoma, Paeoniae Radix, Rehmanniae Radix Preparata became objects of intense quality control (=IQC). Analysis on loss on drying shows Cinnamomi Cortex was unsuitable and was put under the IQC. In case of respective heavy metals, Angelicae Gigantis Radix, Cnidii Rhizoma, Cinnamomi Cortex exceeded the maximum permissible range for Cd. The 3 kinds of sub-standards were put to the IQC. Statistic figures showed a significant correlation (t-test, p<0.01) between country-of-origin and sub-quality rates. Compared to domestic one, imported medicinal herbs were less suitable in regard of acid-insoluble ash, loss on drying and Pb/Hg content. Meanwhile, amounts of Acid-insoluble ash showed positive relation with amounts of Pb (r=0.202) and As (r=0.243) among heavy metals leading to an inference that herbs of which root/rhizome is used for medical purposes attribute its high heavy metal content to the fine earth/sand being stuck to its root stalk.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.1
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• pp.35-42
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• 2007

Thermal discharges from the nuclear power plants into neighboring Korean coastal waters have raised serious disputable arguments from the two parties of local fishermen and scientists involved since late 1970's. To meet the social demands and provide scientific and reasonable solutions, new set of standards have been established which will guide through measuring and processing the various variables and parameters in environmental and fishery impact assessment procedures for the thermal discharge from the nuclear power plants. These are made possible for the first time by the combined efforts by Korean Oceanography Society and Fishery Society. In this paper, Thermal Disharge Impact Index(TI) is proposed by the probability of the local temperatures exceeding critically to local fishery multiplied by the weighted sum of diverse environmental and ecological factors. The TI is essentially conceived to overcome the long-exising bad practices based on the particular excess temperature such as 1. The proposed TI based on the guideline principle proposed by the UNEP(2002) is expected to be practical, economic and self-adaptive. To prove the usefulness of the TI, it is highly recommended to conduct prototype experiments and exercises in a particular nuclear power plant site in the near future.