• Journal of the Institute of Electronics Engineers of Korea CI
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• v.42 no.3 s.303
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• pp.17-28
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• 2005

Recently intelligent characters in computer games have been an important element more and more because they continually stimulate gamers' interests. As a typical method for implementing such intelligent characters, neural networks have been used for training action patterns of opponent's characters and game rules. However, some of the game rules can be abruptly changed and action properties of garners in on-line game environments are quite different according to gamers. In this paper, we address how a neural network adapts to those environmental changes. Our adaptation solution includes two components: an individual adaptation mechanism and a group adaptation mechanism. With the individual adaptation algorithm, an intelligent character steadily checks its game score, assesses the environmental change with taking into consideration of the lastly earned scores, and initiates a new learning process when a change is detected. In multi-user games, including massively multiple on-line games, intelligent characters confront diverse opponents that have various action patterns and strategies depending on the gamers controlling the opponents. The group adaptation algorithm controls the birth of intelligent characters to conserve an equilibrium state of a game world by using a genetic algorithm. To show the performance of the proposed schemes, we implement a simple fighting action game and experiment on it with changing game rules and opponent characters' action patterns. The experimental results show that the proposed algorithms are able to make intelligent characters adapt themselves to the change.

• Environmental Mutagens and Carcinogens
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• v.26 no.4
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• pp.119-124
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• 2006

There are $10{\sim}30%$ polyphenol and $2{\sim}4%$ caffeine in green tea. Caffeine is a kind of alkaloid containing nitrogen which cause stimulation, impatience, headache, insomnia, low birth weight infant. Because of these negative effect, decaffeined beverage came out and decaffeined coffee already have a big market since 1970s. Having proving the physiologic functions of green tea, high consumption of coffee is shifting to green tea. Because of the carcinogenic effect of the organic solvents, decaffeine processing with supercritical carbon dioxide has industrialized and have an advantage in environment-friendly and minimized flavor loss. Decaffeined green tea using supercritical carbon dioxide is considered to be safe but there are not enough study. We investigated the chromosome aberration test with mammalian cell line, CHL. When the cells were treated with 5000, 2000, 1000 ${\mu}g/ml$ and compared with the negative controls, there were no significant(P>0.05) increased chromosome aberration. Same results was observed when adding S9 mixture or not. As a result, water extract of decaffeined green tea using supercritical carbon dioxide does not induce chromosome aberration.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.133-140
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• 1998

The following conclusions are based upon data collected and visual observations made during the performance of the tests : 1. The performance of the erosion control products tested was for a particular set of conditions, and may be expected to differ if any or all of the test parameters were to be changed. If even just one parameter is changed from one test to the next, the results can be expected to be different. 2. Due to the fact that only two replications of each product were tested, we believe that the results presented herein are indicative only and not conclusive. 3. The ECB SC produced the least amount of soil erosion followed by ECB S, ECB C, and Coir No. 2, in that order. 4. All of the erosion control blankets tested significantly reduced soil erosion rates with respect to the bare soil controls. 5. The ECB S produced the smallest water runoff rate, followed closely by ECB SC. Next in order were ECB C and Coir No. 2. 6. All of the erosion control blankets reduced the water runoff rate with respect to the bare soil control. 7. Mesh 2cm There was not much difference in plant height for the four erosion control blankets and the bare soil control plots. the ECB S produced slightly taller plants than the rest of the materials tested. 8. The four erosion control blankets(ECB C, ECB SC, ECB S, and Coir No. 2) produced a larger plant mass than the bare soil plots. The difference between the plant mass for the four erosion control blankets, however, is minimal. 9. The ECB C produced the least percentage of lost seed and the largest percentage of germinating seed. 10. The ECB SC had the second smaller percentage of seed lost, followed closely by ECB S, and then by Coir No. 2. 11. All erosion control blankets had a smaller percentage of seed lost than the bare soil control plots. 12. The ECB C had the second largest percentage of germinating seed, followed closely by ECB SC and Coir No. 2. 13. All erosion control blankets had a larger percentage of germinating seed than the bare soil control plots. 14. The ECB C had the smallest percentage of non-germinating seed, followed by ECB S, Coir No. 2, and ECB SC, in that order. 15. All erosion control blankets had smaller percentages of non-germinating seed than the bare soil control plots.

• Economic and Environmental Geology
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• v.42 no.5
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• pp.501-507
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• 2009

Ordered single-walled hollow aluminogermanate (ALGE) nano-balls(NBs) and nano-tubes(NTs) have been self-assembled from the ALGE precursors having an Al/Ge ratio of 1.33 using simple pH-control. The hollow ALGE NBs with average monodisperse diameters of 5 nm and chemistry of Al/Ge=1.5~1.6 were formed through structural assembly in the ALGE solution (Al/Ge=1.33) highly basified to pH=13(Na/Al=28~30) and followed by immediate acidification to pH=9. When the basified solution(pH=13) were acidified to pH=4, ALGE S-NTs (Short-fiber nano-tubes) with diameters of 3.3 nm, 15~20 nm in length, and chemistry of Al/Ge=2.6~2.8 were successfully synthesized. Whereas the solution was basified to pH=9, and subsequently acidified to pH=4, L-NTs(Long-fiber nano-tubes) with >100 nm in length were synthesized for the first time. The self-assembly of the hollow NBs, S-NTs, and L-NTs form the ALGE precursors can be explained by the degree of $H^+$-dissociation of the -Ge-OH inner surfaces, which was controlled by amount of $Na^+$ and pH conditions of ALGE precursor solutions. This results indicate that target forms of ALGE nanomaterials can be synthesized by simple pH controls.

• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.58-64
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• 1988

The acute oral, intraperitoneal and subacute toxicity of monocrotophos, an insecticide, was studied in albino rats. The acute oral $LD_{50}$ values for female and male rats were 5.0mg/kg and 8.7mg/kg, respectively. Conversely the intraperitoneal $LD_{50}$ values for female and male rats were 4.9mg/kg and 6.0mg/kg, respectively. Plasma cholinesterase (ChE) activity in rats treated with a single dose was the most depressed 4 hours after administration, but returned to normal within 72 hours of administration. Significant depression of body weight gain and food consumption was observed in rats receiving the 3.5mg/kg/day dose level for 28 days as compared with the controls. Additionally plasma ChE activity depression was also observed.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.573-580
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• 2017

The oxicity assesment of Phenanthrene (PHE) has been investigated by using the rate (r) of survival and population growth in rotifer Brachionus plicatilis. The survival rate was determined after 24 h of exposure to PHE. The survival rate of PHE had no effect at a maximum of $300mg\;L^{-1}$. The r was determined after 72 h of exposure to PHE. It was observed that r in the controls (absence PHE) was greater than 0.5, but that it suddenly decreased with an increased concentration of PHE. PHE reduced r in a dose-dependent manner and a significant reduction occurred at a concentration of greater than $37.5mg\;L^{-1}$. The $EC_{50}$ value of r in PHE exposure was $63.7mg\;L^{-1}$. The no-observed-effect-concentration (NOEC) of r in PHE exposure was $18.8mg\;L^{-1}$. The lowest-observed-effect-concentration (LOEC) of r in the PHE exposure was $37.5mg\;L^{-1}$. From the results, the concentration of PHE (greater than $37.5mg\;L^{-1}$) has a toxic effect on the r of B. plicatilis in natural ecosystems. These results(including NOEC, LOEC and $EC_{50}$) might be useful for the Polycyclic aromatic hydrocarbons(PAHs) toxicity assessment in marine ecosystems.

• Journal of Korea Water Resources Association
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• v.51 no.spc
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• pp.1135-1148
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• 2018

Previous studies on reservoir operation have been assumed that the climate in the future would be similar to that in the past. However, in the presence of climate non-stationarity, Robust Optimization (RO) which finds the feasible solutions under broader uncertainty is necessary. RO improves the existing optimization method by adding a robust term to the objective function that controls the uncertainty inherent due to input data instability. This study proposed Robust-SDP that combines Stochastic Dynamic Programming (SDP) and RO to estimate dam operation rules while coping with climate non-stationarity. The future inflow series that reflect climate non-stationarity were synthetically generated. We then evaluated the capacity of the dam operation rules obtained from the past inflow series based on six evaluation indicators and two decision support schemes. Although Robust-SDP was successful in reducing the incidence of extreme water scarcity events under climate non-stationarity, there was a trade-off between the number of extreme water scarcity events and the water scarcity ratio. Thus, it is proposed that decision-makers choose their optimal rules in reference to the evaluation results and decision support illustrations.

• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.385-391
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• 2018

Toxic assessment of PBDEs (BDE-47, BDE-209) has carried out using the rates of population growth in marine phytoplankton, Skeletonema costatum. The population growth rate (r) in S. costatum was determined after 96 hours of exposure to BDE-47 (2,2'4,4'-Tetrabromodiphenyl ether) and BDE-209 (2,2', 4,4'-Decabromodiphenyl ether). It was observed that r-value in the controls (absence PBDEs) was greater than 0.04 and further a decrease was observed in a dose-dependent manner. BDE-47 reduced population growth rate in a dose-dependent manner and a significant reduction occurred at a concentration greater than $0.31mgL^{-1}$, but BDE-209 had no effect on population growth rate even at concentrations greater than $125mgL^{-1}$. The population growth rate in the presence of BDE-47 and BDE-209, $EC_{50}$ values were $0.55mgL^{-1}$ and >$125mgL^{-1}$, and NOEC values were $0.16mgL^{-1}$ and >$125mgL^{-1}$, respectively. Therefore, BDE-47 is considered to be about over 80 times more harmful than BDE-209. In this study, the ecotoxic assessment based on population growth rate in S. costatum can be used as a baseline data for establishment of environment standard quality of BDE-47 and BDE-209 in the marine environment.

• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.154-158
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• 2019

BACKGROUND: 'Shiranuhi' mandarin is a major cultivar among all late ripening type of citrus, and is widely cultivated in Korea. However, many farmers have reported scion root problems in their orchard resulting in reduced flowering and fruiting. It is necessary that the physiology of scion-rooted 'Shiranuhi' mandarin trees is further understood. METHODS AND RESULTS: This experiment was conducted to understand the growth response and physiology of scion-rooted 'Shiranuhi' mandarin hybrids. In our study, 'Shiranuhi' mandarin trees were divided into two groups: trees without scion roots (control) and trees with scion roots. The experiment was conducted in Seogwipo of Jeju, with ten replicates for each group. Growth of trees with scion roots was more vigorous and the trees were taller than the controls. Tree height and trunk diameter of scion-rooted trees were significantly higher than those of control trees. Exposed length of rootstocks of scion-rooted trees was significantly lower (by about 2 cm) than that of control trees (8.6 cm). In terms of root nutrition, carbon contents of scion-rooted trees was significantly lower than that of control trees, but nitrogen and potassium concentrations in scion roots were significantly higher than those in control roots. CONCLUSION: Based on the results, we infer that growth of scion-rooted trees was very vigorous and the content of nitrogen in these roots was higher than that in the control tree roots. Thus, the carbon/nitrogen ratio of scion roots was significantly lower than that of the control roots.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.724-732
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• 2020

Phytophthora capsici is the organism that causes Phytophthora blight which infects red pepper plants prolifically, ultimately leading to crop loss. A previous study revealed that Enterobacter asburiae ObRS-5 suppresses Phytophthora blight in both red pepper and Ligularia fischeri plants. In order to determine whether the induced systemic resistance (ISR) was triggered by pre-infection with the ObRS-5 strain, we conducted quantitative PCR using primers for PR1, PR4, and PR10, which correlate with systemic resistance in red-pepper plants. In our results, red pepper plants treated with the ObRS-5 strain demonstrated increased expression of all three systemic resistance genes when compared to controls in the glasshouse seedling assay. In addition, treatment of red peppers with the ObRS-5 strain led to reduced Phytophthora blight symptoms caused by P. capsici, whereas all control seedlings were severely affected. Perhaps most importantly, E. asburiae ObRS-5 was shown to induce the ISR response in red peppers without inhibiting growth. These results support that the defense mechanisms are triggered by ObRS-5 strain prior to infection by P. capsici and ObRS-5 strain-mediated ISR action are linked events for protection to Phytophthora blight.