• Korean Journal of Ecology and Environment
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• v.41 no.spc
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• pp.86-92
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• 2008

This study was conducted to determine removal effect on phytoplankton (chlorophyll-${\alpha}$ as whole algae) and cyanobacteria by a fish Pseudorasbora parva and macroinvertebrate Palaemon paucidens in September 2006. Three treatments with 25 (T1), 50 (T2) and 100 (T3) individuals along with control (C1, no input fish), and two treatments with 25 (T4) and 50 (T5) individuals along with control (C1) were made for fish and macroinvertebrate, respectively. The initial concentrations of chlorophyll-${\alpha}$ $(Chl_i)$ in each 10L test tank were set up for the levels of $95{\sim}100{\mu}g\;L^{-1}$ and the daily values were monitored in the test tank during 7 days. In the lab tests, P. parva did not show Chl-${alpha}$ removal effect; the removal rate of Chl-${alpha}$ for P. parva was -58% in T1, -56% in T2, and 61% in T3 during the test period. In contrast, P. paucidens. in the treatments of T4 and T5 removed the phytoplankton effectively and the removal effect were appeared to be 33% and 22%, respectively. Also, P. paucidens showed high feeding efficiency in the removal of cyanobacteria. The levels of cyanobacteria were greatly lowed from 6,048 to 927 cells $mL^{-1}$ in T4 and from 6,539 to 1,053 cells $mL^{-1}$ in T5, resulting in 85% and 84% in the removal effect, respectively. Our results for biomanipulation tests suggest that P. paucidens may be used as a potential candidate organism for algae control in spite of the preliminary results by laboratory tests.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.429-438
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• 2007

Early growth vigor(EGV) is one of the physiological characteristics that may contribute to the increase of genetic yield potential and radiation use efficiency by closing the canopy earlier. To estimate the genotypic variation of EGV, determine the relationships among the related traits, and identify the rapidly growing genotypes and indirect indicator for selection in breeding program, the evaluation of EGV and EGV-related traits was conducted for a total of 140 rice varieties consisting of 101 Korean, 25 Northern China and 14 IRRI-bred rice varieties in a serial sowing experiment in plastic rain shelter and plastic-covered nursery bed in 2003. EGV defined as the amount of leaf area and/or dry weight produced early in the season and the EGV-related traits such as length and breadth of the $2^{nd}\;and\;3^{rd}$ leaves showed highly significant positive correlation with the embryo and seed weight. Especially, the genotypic variation in the length of the third leaf was explained over 90% of genotypic variation in the seed weight. Owing to a large effect of seed size on EGV and its related traits, vigor measurements were adjusted based on their linear or exponential relationships with seed weight for excluding the seed weight effect. EGV and its related-traits adjusted for seed weight also showed big variation among genotypes. Increased EGV was genetically correlated with increases in breadth and length of early leaves. The broad-sense heritability for EGV was significantly high(81%), but lower than those of leaf breadth(90% for the $2^{nd}$ leaf and 93% for the $3^{rd}$ leaf) and length(87% for the $2^{nd}$ leaf and 89% for the $3^{rd}$ leaf). Significantly positive genetic correlations were found between EGV and the breadth and length of early leaves. The high heritability of early leaf breadth and length coupled with their strong genetic correlation with EGV indicated that the breadth and length of the $2^{nd}\;and\;3^{rd}$ leaf would be used as good indirect indicators for EGV selection in rice breeding program.

• Journal of Life Science
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• v.20 no.11
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• pp.1711-1717
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• 2010

In this study, fibrinolytic activities of fermented yellow agabean (FYA) and black agabean (FBA), and the antioxidation efficiencies of 70% ethanol extract of fermented yellow agabean (FYAE) and black agabean (FBAE) were investigated by selecting Bacillus sp. sm26 strain. Fibrinolytic activities of FYA and FBA were $6.38{\pm}0.5$ and $6.83{\pm}0.5\;U/ml$, which were 1.3 and 1.4 times higher than that of FSB, respectively. With regard to total phenolic contents, FYAE and FBAE were $3.40{\pm}0.44\;mg/g$ and $2.45{\pm}0.20\;mg/g$ respectively, suggesting that their contents were about twice as high as that of fermented soybean extract (FSBE) used as a control. In comparison with FSBE, total protein and sugar contents of FYAE were $0.56{\pm}0.11$ and $2.41{\pm}0.48\;mg/g$, respectively, and those of FBAE were $0.39{\pm}0.12$ and $2.72{\pm}0.63\;mg/g$, respectively. This result suggests that FYAE was 4.7 and 1.7 times higher than FSBE, respectively. The DPPH radical scavenging activity of FBAE was 79% at 1 mg/ml, which was highest among the fermented bean extracts, and was twice as high as FSBE in regards to activity. In addition, FBAE exhibited the highest reducing power at 1 mg/ml, which was higher than FSBE by two-fold. With regard to lipid peroxidation, FBAE and FYAE were 93% and 80% at 1 mg/ml, which were 3 and 2.5 times higher than FSBE, respectively. Of note, the hydrogen peroxide scavenging activities of FBAE and FYAE were 82% and 54% at 1 mg/ml, offering activity that was 4 and 2.5 times higher than FSBE, respectively. Based on these results, the fibrinolytic activity and antioxidation efficiency of the fermented agabeans were significantly higher than other soybeans. Therefore, these studies may suggest that the functional agabeans can be a potential candidate for a natural functional food.

• Journal of Life Science
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• v.22 no.11
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• pp.1477-1486
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• 2012

This study was performed to determine the effect of onion peel extract using 70% ethanol and 95% ethanol on its anti-oxidation activity, small intestine length, and intestinal villi of high-fat fed mice. Five percent of each onion peel extract using 70% and 95% ethanol showed significant decrease of E. coli and Listeria monocytogenes. Total phenolic contents of onion peel extracts using 70% and 95% ethanol were $166.89{\pm}0.03$ mg/g and $160.89{\pm}0.13$ mg/g, respectively. In anti-oxidation activity, DPPH radical scavenging activity and SOD-like activity of onion peel extracts were higher at 100 ug/ml concentration. The obese mice were fed high-fat diets supplemented by 1, 3, and 5% of the onion peel extracts using 70% and 95% ethanol for 4 weeks. Body weight, feed intake, feed efficiency, small intestine weight, length, villi's length, and number of bacteria in intestine were determined. Body weight of mice fed 5% of onion extracts using both 70% and 95% ethanol was significantly lower than that of control (p<0.05). However, feed intake was increased in mice fed 5% of onion extracts at both fermented ethanol levels. Small intestine weight and length of mice showed no significant change with supplementation of the onion peel extracts. However, length of small intestine villi was significantly longer than that of control. Total bacteria counts of Cl. Perfringenes and E. coli in small intestine of the mice were significantly reduced by supplementation of 5% of onion extract using ethanol, while lactic acid bacteria were increased. These results suggest that 5% of onion peel extracts using ethanol at either 70% or 95% concentration have potential to be used as an additive for body weight control and enhanced gut health; however, more research on its effectiveness is needed.

• Korean Journal of Digital Imaging in Medicine
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• v.5 no.1
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• pp.64-77
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• 2002

DR has had an important fact not only in the department of radiology but also in productivity or work efficiency of a whole hospital. The environment of DR has more various parameter than CR, so it is able to supply high quality of medical services. The current environment of radiology department in each hospital has been changed from Film-Screen system to DR through Full-PACS. This hospital which uses Full-PACS became to study the proper condition of CR and DDR and how the image quality of them is expressed among general photographing systems in the DR environment. From this experiment, the image quality of DDR is better than CR under the same exposure condition. And in the DDR system, the score of image which uses AEC is a little higher than the score which doesn't use it. Especially it can be known that the function of AEC of DDR is useful to improve the image quality in the part of skull and chest. (The function of AEC : It is the tool that detects the ionized current of x-ray which goes through objects with using the ion chamber which is in the detector. Also it controls the examination of X-ray when the proper density is reached.) Because the proper degree of density can be represented by this system, the photographing can be taken much easily without consideration of the exposure condition with the thickness of various objects. From the result of this experiment, it can be known that the selection of proper exposure condition plays an important rule to gain good Image Quality. More researches will be necessary about DDR system which has potential ability in the future.

• Journal of Korean Society for Geospatial Information Science
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• v.8 no.1 s.15
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• pp.51-63
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• 2000

Dynamic traffic assignment(DTA) has been a topic of substantial research during the past decade. While DTA is gradually maturing, many aspects of DTA still need improvement, especially regarding its formulation and solution algerian Recently, with its promise for In(Intelligent Transportation System) and GIS(Geographic Information System) applications, DTA have received increasing attention. This potential also implies higher requirement for DTA modeling, especially regarding its solution efficiency for real-time implementation. But DTA have many mathematical difficulties in searching process due to the complexity of spatial and temporal variables. Although many solution algorithms have been studied, conventional methods cannot iud the solution in case that objective function or constraints is not convex. In this paper, the genetic algorithm to find the solution of DTA is applied and the Merchant-Nemhauser model is used as DTA model because it has a nonconvex constraint set. To handle the nonconvex constraint set the GENOCOP III system which is a kind of the genetic algorithm is used in this study. Results for the sample network have been compared with the results of conventional method.

• Geophysics and Geophysical Exploration
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• v.11 no.2
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• pp.127-136
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• 2008

To identify the potential area of gas hydrate in the Ulleung Basin, 2-D and 3-D seismic surveys using R/V Tamhae II were conducted in 2005 and 2006. Seismic survey equipment consisted of navigation system, recording system, streamer cable and air-gun source. For reliable velocity analysis in a deep sea area where water depths are mostly greater than 1,000 m and the target depth is up to about 500 msec interval below the seafloor, 3-km-long streamer and 1,035 $in^3$ tuned air-gun array were used. During the survey, a suite of quality control operations including source signature analysis, 2-D brute stack, RMS noise analysis and FK analysis were performed. The source signature was calculated to verify its conformity to quality specification and the gun dropout test was carried out to examine signature changes due to a single air gun's failure. From the online quality analysis, we could conclude that the overall data quality was very good even though some seismic data were affected by swell noise, parity error, spike noise and current rip noise. Especially, by checking the result of data quality enhancement using FK filtering and missing trace restoration technique for the 3-D seismic data inevitably contaminated with current rip noises, the acquired data were accepted and the field survey could be conducted continuously. Even in survey areas where the acquired data would be unsuitable for quality specification, the marine seismic survey efficiency could be improved by showing the possibility of noise suppression through onboard data processing.

• Membrane Journal
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• v.21 no.1
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• pp.46-54
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• 2011

In this study, combined effect of airflow rate, $TiO_2$ concentration, solution pH and $Ca^{+2}$ addition on HA (humic acid) fouling in submerged, photocatalytic hollow-fiber microfiltraiton was investigated systematically. Results showed that UV irradiation alone without $TiO_2$ nanoparticles could reduce HA fouling by 40% higher than the fouling obtained without UV irradiation. Compared to the HA fouling without UV irradiation and $TiO_2$ nanoparticles, the HA fouling reduction was about 25% higher only after the addition of $TiO_2$ nanoparticles. Both adsorptive and hydrophilic properties of $TiO_2$ nanoparticles for the HA can be involved in mitigating membrane fouling. It was also found that the aeration itself had lowest effect on fouling mitigation while the HA fouling was affected significantly by solution pH. Transient behavior of zeta potential at different solution pHs suggested that electrostatic interactions between HA and $TiO_2$ nanoparticles should improve photocatalytic efficiency on HA fouling. $TiO_2$ concentration was observed to be more important factor than airflow rate to reduce HA fouling, implying that surface reactivity on $TiO_2$ naoparticles should be important fouling mitigation mechanisms in submerged, photocatalyic microfiltraiton. This was further supported by investigating the effect of $Ca^{+2}$ addition on fouling mitigation. At higher pH (= 10), addition of $Ca^{+2}$ can play an important role in bridging between HA and $TiO_2$ nanoparticles and increasing surface reactivity on nanoparticles, thereby reducing membrane fouling.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.403-408
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• 2010

This study was carried out to investigate the physiological responses of $Rhododendron$ $mucronulatum$ Turcz. and $R.$ $indicum$ (L.) Sweet seedlings with 0%, 35%, 55% and 75% shading of full sunlight in polyethylene film house. The shading treatments were performed during the late growth season for each species (from Sept. 9 to Nov. 5, 2008). The shading treatment was effective in reducing the daily temperature by 0.9 to $1.7^{\circ}C$ during September and by 0.8 to $1.7^{\circ}C$ during October. Before the shading treatments, the water content of $R.$ $mucronulatum$ and $R.$ $indicum$ amounted to 68.5% and 66.3%, respectively. The water contents of two species after 75% shading treatment period decreased to 66.2% (3.4% reduction) and 65.9% (0.6% reduction), respectively. Notably, both species had a similar tendency indicating less reduction rate of water content with 75% shading. $R.$ $indicum$ showed higher photosynthetic capacity with higher level of shading, and its photosynthetic capacity reached the highest level ($9.63{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). On the other hand, shading-treated $R.$ $indicum$ showed higher intercellular $CO_2$ concentration, stomatal conductance and transpiration rate (55% shading > 35% shading > 75% shading) than non-treated ones. In addition, non-treated seedlings showed higher water use efficiency than treated ones. In particular, it was found that the leaf color of $R.$ $mucronulatum$ turned equivalent to purple under full sunlight, while its leaf color kept equivalent more to green with higher level of shading, as evidenced even in naked eyes. According to comprehensive analysis using Munsell Color Chart on potential leaf color variations of $R.$ $mucronulatum$ depending on the level of shading, it was found that relatively many leaf colors under full sunlight were equivalent to R (red) and Y (yellow) chart, while relatively many leaf colors with higher level of shading were equivalent to G (green) and Y chart, where the latter still showed green color.

• Journal of Korean Society of Forest Science
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• v.78 no.2
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• pp.151-159
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• 1989

The present study has been designed to define the effects of photosynthetically active radiation, leaf temperature, and water stress on photosynthesis and respiration of leaves of four oak species (Quercus mongolica, Quercus aliens, Quercus variabilis, and Quercus serrate). The results obtained are as follows : 1. The estimated light compensation points at which Pn approached zero were 38, 24, 20, and $18{\mu}Em^{-2}s^{-1}$ for Q. aliens, Q. variabilis, Q, mongolica, and Q. serrate, respectively. The light saturation points occurred at $500{\mu}Em^{-2}s^{-1}$ in three oak species except Q, aliens. 2. The maximum rates of Pn were 19.7, 15.2, 11.2, and 11.0 mg $CO_2$ $dm^{-2}h^{-1}$ for Q. variabilis, Q. serrate, Q. monglica, and Q. aliens leaves, respectively. 3. The transpiration rates of Q. variabilis and Q. serrate leaves were slightly higher than those of Q. mongolica and Q. aliens leaves at various photosynthetically active radiations(PAR), but cuticular transpiration rates at dark were similar in four oak species. 4. The optimum photosynthesis occurred at $25^{\circ}C$ in Q. aliens, Q. variabilis, and Q. serrate leaves, but $20^{\circ}C$ in Q. mongolica leaves. In four oak species, the net photosynthesis approached zero at about $40^{\circ}C$. 5. The dark respiration rates of leaves exhibited the following ranking of species : Q, variabilis > Q. mongolica > Q. aliens > Q. serrate. 6. The maximum productive efficiency (Pg/Rd) of leaves occurred highest in Q, serrate at $20^{\circ}C$, then in Q. mongolica at $20^{\circ}C$, then in Q, aliens at $25^{\circ}C$, and finally in Q. variabilis at $15^{\circ}C$. 7. The decrease of net photosynthesis in Q. serrate began at about -1.2 MPa, and then approached zero at -2.9 MPa of leaf water potential. The decrease of net photosynthesis began at 3% of water loss, and then approached zero at 17.5% of water loss. 8. As indicated by tissue-water relations parameters, it may be suggested that Q. aliens and Q. variabilis are more tolerant and favored on xeric forest soils than Q. mongolica and Q. serrate.