• Journal of Radiation Protection and Research
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• v.44 no.2
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• pp.64-71
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• 2019

Background: It is very difficult to distinguish between a radioactive contamination source and background radiation from natural radionuclides in the marine environment by means of online monitoring system. The objective of this study was to investigate a statistical process for triggering abnormal level of count rate data measured from our on-line seawater radioactivity monitoring. Materials and Methods: Count rate data sets in time series were collected from 9 monitoring posts. All of the count rate data were measured every 15 minutes from the region of interest (ROI) for $^{137}Cs$ ($E_{\gamma}=661.6keV$) on the gamma-ray energy spectrum. The Shewhart ($3{\sigma}$), CUSUM, and Bayesian S-R control chart methods were evaluated and the comparative analysis of determination methods for count rate data was carried out in terms of the false positive incidence rate. All statistical algorithms were developed using R Programming by the authors. Results and Discussion: The $3{\sigma}$, CUSUM, and S-R analyses resulted in the average false positive incidence rate of $0.164{\pm}0.047%$, $0.064{\pm}0.0367%$, and $0.030{\pm}0.018%$, respectively. The S-R method has a lower value than that of the $3{\sigma}$ and CUSUM method, because the Bayesian S-R method use the information to evaluate a posterior distribution, even though the CUSUM control chart accumulate information from recent data points. As the result of comparison between net count rate and gross count rate measured in time series all the year at a monitoring post using the $3{\sigma}$ control charts, the two methods resulted in the false positive incidence rate of 0.142% and 0.219%, respectively. Conclusion: Bayesian S-R and CUSUM control charts are better suited for on-line seawater radioactivity monitoring with an count rate data in time series than $3{\sigma}$ control chart. However, it requires a continuous increasing trend to differentiate between a false positive and actual radioactive contamination. For the determination of count rate, the net count method is better than the gross count method because of relatively a small variation in the data points.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.9
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• pp.2266-2284
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• 2012

Recent studies have indicated that a significant improvement in wireless video throughput can be achieved by Cross Layer Design with Side-information (CLDS) protocols. In this paper, we derive the operational rate of a CLDS protocol operating over a realistic wireless channel. Then, a Rate-Distortion (R-D) empirical model for above-capacity Scalable Video Coding (SVC) is deduced to estimate the loss of video quality incurred under inaccurate rate estimation scenarios. Finally, we develop a novel Unequal Error Protection (UEP) scheme which leverages the characteristics of LDPC codes to reduce the distortion of video quality in case of typically-observed burst wireless errors. The efficacy of the proposed rate adaptation architecture over conventional protocols is demonstrated by realistic video simulations using actual IEEE 802.11b wireless traces.

• Research in Plant Disease
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• v.18 no.4
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• pp.277-289
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• 2012

The total number of requests and associated specimens for the diagnosis of virus infection were 573 and 2,992, respectively, on crops from agricultural places of farmers, Agricultural extension services and so forth for 5 years from 2007. The total number of virus tests was 13,325. The number of species of viruses infected on the submitted crops was 21 in 2007, 15 in 2008, 23 in 2009, 21 in 2010 and 17 in 2011. The newly recorded viruses were Tobacco leaf curl virus (TbLCV) in 2007, Tomato yellow leaf curl virus (TYLCV) in 2008, Impatience necrotic spot virus (INSV) and Radish mosaic virus (RaMV) in 2009, and Beet western yellows virus (BWYV) in 2010. Forty virus species including Alfalfa mosaic virus were detected over 5 years. The ten most frequently detected virus species were Cucumber mosaic virus (CMV), Tomato spotted wilt virus (TSWV), Tomato leaf curl virus (TYLCV), Cucumber green mottle mosaic virus (CGMMV), Broad bean wilt virus 2 (BBWV2), Zucchini yellow mosaic virus (ZYMV), Melon necrotic spot virus (MNSV), Pepper mild mottle virus (PMMoV), Watermelon mosaic virus (WMV) and Pepper mottle virus (PepMoV). The types of crops submitted from agricultural places were 51 in total and the ten most frequently submitted crops were red pepper, tomato, paprika, watermelon, melon, rice, cucumber, corn, radish and gourd. The total request rate for the top 10 crops and top 20 crops was 81.6% and 94.2%, respectively. Eight pepper infecting virus species included CMV, and the average infection rate was 24.6% for CMV, 18.9% for PMMoV and 14.7% for TSWV. Seven kinds of double infection were detected in pepper including BBWV2+CMV at 14.7% on average, and four types of triple infection including BBWV2+CMV+PepMoV at 0.9% on average. Six virus species detected on tomato including TYLCV, and the average infection rate was 50.6% for TYLCV, 14.5% for TSWV and 10.9% for Tobacco leaf curl virus (TbLCV). The mixed infection of CMV+TSWV on tomato was 3.9% on average and of Tomato mosaic virus (ToMV)+TYLCV was 0.4% on average. Five viruses detected on watermelon included MNSV and the average infection rate was 37.0% for MNSV, 20.4% for CGMMV, 18.1% for ZYMV and 17.8% for WMV. The mixed infection rate on watermelon was CMV+MNSV and WMV+ZYMV having an average infection rate of 0.7% and 5.0%, respectively. The average infection rates on melon were 77.6% for MNSV, 5.6% for CMV and 3.3% for WMV. Mixed infections of CMV+MNSV occurred on melon with an average infection rate of 13.5%.

• Proceedings of the KWS Conference
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• 2007.11a
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• pp.263-265
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• 2007

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.05a
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• pp.141-141
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• 2015

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.2
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• pp.79-89
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• 2009

For preliminary diagnosis on current fishing ground environment and basic information for establishment of effective and rational management policy in fisheries resources protection area, water and sediment quality and changes of total area in the 10 marine protection areas designated for fisheries resources management in Korea were assessed. Results showed that environmental quality in these areas has been degraded by pollution sources, coastal utilization and development stress, etc. The pattern and degree of contamination differed by protection areas, suggesting that it is necessary for optimum environmental management plan considering the regional characteristics. The total designated area of protection areas in 2003 changed by $-22.9{\sim}2.4%$, on average -6.4%, compared with the first year of designation; Wando-Doam Bay showd the highest increase rate (2.4%), and Hansan Bay has the highest decrease rate (-22.9%) Decrease rate of land and sea in total area showd 6.1% and 6.6%. An integrated management of environmental data in protection areas is required for systematic assessment. Therefore, the suitable environmental and information management is needed specifically considering the environment characteristics such as development and utilization conditions of land and sea area Furthermore, bemuse urbanization and industrialization threats the junctions of the protection areas, authorized ministry (MIFAFF) should develope and establish monitoring and management procedures based on the related laws.

• Tunnel and Underground Space
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• v.19 no.6
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• pp.526-533
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• 2009

This study presents Mine Green Framework(M.G.F) which can protect the slope of rock and tailings. M.G.F method provides the fiber frame which helps the growth of the plant in the barren site like mined rock slope. M.G.F system consists of the polyester fiber mat, soil, seeds and anchors for the attachment. The optimum rate of filling materials was figured out by many germination tests in order to improve the effect of filling materials and the optimum rate of filling materials was applied in four test sites individually. High rooting rate over 70% was confirmed in all field tests. Especially the moisturizer was the most important component of filling materials and it could make the better condition for the plants.

• Journal of Radiation Protection and Research
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• v.16 no.1
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• pp.15-24
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• 1991

Radon-222 exhalation rate from several domestic building materials were experimentally measured by using radon cup method, in which a CR-39 plastic is used as a passive radon detector. The radon detection factor of CR-39 detector determined in a series of calibration experiments was $0.164{\pm}0.005(tracks\;cm^{-2}/Bq\;d\;m^{-3})$, which is consistent with those reported by other investigators. The radon exhalation rates of several building materials (brick, red brick, concrete block, granite plate, concrete floor and wall) ranges from $6.8{\times}10^{-6}\;(granite plate)\;to\;75.0{\times}10^{-6}Bq/m^2-sec(brick)$ with the increasing order of granite plate, red brick, concrete wall, concrete block, concrete floor and brick. It showed that the CR39 radon cup can be efficiently utilized in measuring the radon-222 gas exhalation rate from building materials.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.205-211
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• 2016

Excessive exposure to chemicals in the workplace can cause poisoning and various diseases. Thus, for the protection of labor, it is necessary to examine the exposure of people to chemicals and risks from these materials. The purpose of this study is to evaluate semi-quantitative health risks of exposure to harmful chemical agents in the context of carcinogenesis in a latex glove manufacturing industry. In this cross-sectional study, semi-quantitative risk assessment methods provided by the Department of Occupational Health of Singapore were used and index of LD50, carcinogenesis (ACGIH and IARC) and corrosion capacity were applied to calculate the hazard rate and the biggest index was placed as the basis of risk. To calculate the exposure rate, two exposure index methods and the actual level of exposure were employed. After identifying risks, group H (high) and E (very high) classified as high-risk were considered. Of the total of 271 only 39 (15%) were at a high risk level and 3% were very high (E). These risks only was relevant to 7 materials with only sulfuric acid placed in group E and 6 other materials in group H, including nitric acid (48.3%), chromic acid (6.9%), hydrochloric acid (10.3%), ammonia (3.4%), potassium hydroxide (20.7%) and chlorine (10.3%). Overall, the average hazard rate level was estimated to be 4 and average exposure rate to be 3.5. Health risks identified in this study showed that the manufacturing industry for latex gloves has a high level of risk because of carcinogens, acids and strong alkalisand dangerous drugs. Also according to the average level of risk impact, it is better that the safety design strategy for latex gloves production industry be placed on the agenda.

• Fire Science and Engineering
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• v.30 no.4
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• pp.59-64
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• 2016

The PSD (Platform Screen Door System) has been installed to enhance the passengers' safety. A total of 592 stations operate the PSD system, which is almost 71.8% of all stations in South Korea. This study compared the opening rate between the PSD and train door, and calculated the exact amount of passengers at peak time. In addition, the evacuation time was simulated by Pathfinder 2015 with the exact input data. Some of the high density stations have extremely high dangerous points about the passengers' evacuation at some situations by the PSD door opening rate. In particular, due to the interference of a fixed door, when it stops at 7 m less than the regular position, its opening rate becomes less than half of the normal state. To solve this problem, it should be made possible to open the fixed door by changing it to an emergency door or improving the PSD module system.