• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.72-73
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• 2009

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2006.06a
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• pp.227-228
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• 2006

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.480-484
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• 2002

Accumulation of cadmium (Cd) was investigated in organs (gill, liver, kidney, intestine) of olive flounder (Paralichthys olivaceus) exposed to sub-lethal concentration (5, 10, 50, 100 $\mu$g/L) of Cd for 30 days. Cd exposure resulted in an increased Cd accumulation in liver of flounder for exposure periods and Cd concentration, and Cd accumulation increased linearly with the exposure time. At 20 days of Cd exposure. the order of Cd accumulation in organs was Bill>intestine>liver>kidney and after 30 days of exposure, Cd accumulation in organs was intestine>liver>gill>idney. An inverse relationship was observed between the accumulation factor (AS) and the exposure level, but AE shows an increase with exposure time.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2010.05a
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• pp.321-322
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• 2010

• Sleep Medicine and Psychophysiology
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• v.14 no.1
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• pp.42-48
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• 2007

Introduction: Detrended fluctuation analysis (DFA) is used as a way of studying nonlinearity of EEG. In this study, DFA is applied on sleep EEG of normal subjects to look into its nonlinearity in terms of EEG channels and sleep stages. Method: Twelve healthy young subjects (age：$23.8{\pm}2.5$ years old, male：female=7：5) have undergone nocturnal polysomnography (nPSG). EEG from nPSG was classified in terms of its channels and sleep stages and was analyzed by DFA. Scaling exponents (SEs) yielded by DFA were compared using linear mixed model analysis. Results: Scaling exponents (SEs) of sleep EEG were distributed around 1 showing long term temporal correlation and self-similarity. SE of C3 channel was bigger than that of O1 channel. As sleep stage progressed from stage 1 to slow wave sleep, SE increased accordingly. SE of stage REM sleep did not show significant difference when compared with that of stage 1 sleep. Conclusion: SEs of Normal sleep EEG showed nonlinear characteristic with scale-free fluctuation, long-range temporal correlation, self-similarity and self-organized criticality. SE from DFA differentiated sleep stages and EEG channels. It can be a useful tool in the research with sleep EEG.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.381-386
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• 2004

To develop accurate and predictive global carbon cycle models, it is important to understand the change of accumulated carbon for many ecosystems according to successional stage. In this study, I measured total biomass, litter and soil organic matter contents through an aerial photo and field observation. As a result, accumulated organic matter contents per unit area (kg $m^{-2})$ of three communities composed at grassland were 7.00 kg $m^{-2}$, in Solidago altissima community, 9.18 kg $m^{-2}$, in Imperata cylindrica community, and 12.68 kg $m^{-2}$, in Miscanthus sinensis community, respectively. Accumulated total organic matter contents was high in Miscanthus sinensis community at later succession stage but soil carbon was low. In Miscanthus sinensis community, highly accumulated organic matter contents was resulted from increasing of biomass comparison with that of the other two communities. The pattern of accumulated organic matter contents was changed by changing of the dominant community due to progressing in succession. The accumulated carbon in temperate grassland will be increased with progressing in succession.

• Korean journal of applied entomology
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• v.18 no.1 s.38
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• pp.43-48
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• 1979

This study was conducted to detect lead which is exhausted with gas from running automobiles and is considered to accumulate in cropping lands. Soil samples were taken from uplands and paddy fields with different distance from highways. atonic absorption spectrophotometer was applied for analysis. Results obtained are summarized as follows: 1. In the areas of Seoul toll gate and Jookjeon, Gyeonggi province, soils of fields within $3\~5$ meters from highway appeared to contain $11\~110\;ppm$ of lead. On the other hand, soils outside of $3\~5$ meters showed only natural background level of lead. 2. The maximum concentration of lead in Hwoedeuk area (Choong-nam p개vince) was 16.3 ppm and those of Kimhae and Dongrae areas were about 12 ppm. Low concentration of $1\~4\;ppm$ was observed in the areas, south of Daejeon along the Honam and Namhae highways. 3. Lead seemed to accumulate in the soil surface within the range of 0 to 5 centimeters which anable to expect little translocation to deeper layer of the soil. 4. lost of arable lands locates at least 15 meters apart from highways so that lead concentrations were lower than expected. No damage could be speculated with the present concentration of lead analyzed. This does not deny the necessity to the long term dectect of the possible pollutant.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.438-442
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• 2010

우리나라의 산림면적은 연도가 경과함에 따라 감소한 반면, 임목축적은 지속적으로 증가하였으며, 임상별 면적과 축적은 침엽수의 비중이 가장 높고 혼효림, 활엽수 순으로 나타나고, 영급은 현재 III, IV영급이 많이 분포하는 영급구조로 변화되었다. 또한 임목축적별 건당 피해면적과 재적, 피해면적당 피해수량은 임목축적이 증가함에 따라 증가하는 경향이 있었다. 또한, 피해면적과 재적이 급격히 증가되는 임목축적 3억$m^3$구간은 95년 이후로 이 당시 임목영급은 II, III영급으로 과거보다 산림연료가 풍부해 지는 시기며, 숲가꾸기 단계상 간벌단계로 임목간 밀도가 심하고 고사지의 발생 등 사다리형 연료 발달이 쉬워 대형 산불이 자주 발생한 것으로 판단된다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2006.06a
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• pp.225-226
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• 2006

• Korean Journal of Weed Science
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• v.16 no.2
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• pp.150-159
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• 1996

This study was conducted to investigate the inhibition of protox activity and the PPIX accumulation of the oxyfluorfen-tolerant and-susceptible rice cultivars with barnyardgrass, a typical susceptible weed in accordance by oxyfluorfen treatment. The susceptible rice cultivars and barnyardgrass showed more inhibition of protox activity due to the treatment of oxyfluorfen than the tolerant rice cultivars. Especially in the concentration at $10^{-6}$M treatment, protox activity of the susceptible rice cultivars and barnyardgrass were the completely inhibited but the tolerant rice cultivars kept 32~59% of activity compared to the control. As the treatment concentration increased, the content of PPIX accumulation increased and it increased untill four hours of light exposure but it tended to decrease these after. The content of PPIX accumulation by the treatment of oxyfluorfen was more pronounced in the light condition than in the dark. Under the light and dark conditions, the susceptible rice cultivars and barnyardgrass showed more PPIX accumulation than the tolerant rice cultivate. Especialiy the susceptible barnyardgrass had more than the rice. With the treatment of GC and DA, tetrapyrrole biosynthesis inhibitor, the herbicidal activity by oxyfluorfen was inhibited, and the susceptible rice cultivars and barnyardgrass tended to have less effective than the tolerant rice cultivars and the content of chlorophyll or PPS accumulation tended to be similar.