• Korean Journal of Weed Science
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• v.9 no.3
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• pp.183-200
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• 1989

An experiment was conducted at the greenhouse of the International Rice Research Institute in 1987 to find out the character of dry matter production, the potential seed production ability and the ecological and physiological strategies to adaptation. For these, two rice cultivars, IR64(lowland rice) and UPLRi-5(upland rice), and seven weed species were used ; Echinochloa glabrescens Munro ex Hook. f., E. cress-galls ssp. hispidula (Retz.) Honda, E. colons (L.) Link, Monochoria vaginalis (Burin. f.), Ludwigia octovalvis Jacq.) Raven, Fimbristylis miliacea Vahl and Cyperus difformis L. Adaptation strategies of weed species varied by species. However, they had efficient seed production strategy through different ways. In general, sedge weed species (F. miliacea and C. difformis) produced great amount of seeds at the expense of seed size through greater ratooning ability and low relative dry weight for flowering. For broadleaved weed species, greater number of descendants were obtained through high plasticity and low relative dry weight for flowering (M. vaginalis) or greater growth ability through effective photosynthetic efficiency (L. octovalvis). Grass weed species, on the other hand, produced their seeds through effective growth (net assimilation rate and relative growth rate), high ratooning ability (except E. crus-galls ssp. hispidula) or low relative dry weight to maximum dry weight for flowering (E. glabrescens). The harvest indices of the weed species were considerably lower than those of rice. Fimbristylis miliacea had the greatest ratooning ability followed by C. difformis, E. colons and E. glabrescens. The greatest seed productivity was recorded by C. difformis (279, 000) and L. octovalvis (268,000) while rice produced the least number of seeds (1300-6100). Log seed weight had a negative linear relationship with log seed number (y=6.30-1.48X, $R=-0.965^{**}$). For all species plant plasticity response was not directly correlated with mortality response.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.28-34
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• 2006

Laboratory column tests using $Cl^-$ tracer were conducted to study the correlation of soil particle distribution and hydrodynamic dispersion mechanism with three kinds of ununiformed soil samples, in which the ratio of gravel and sand versus silt and clay is 24.5 for S-1 soil, 4.48 for S-2 soil, and 0.4 for S-3 soil. Chloride breakthrough curves with time were fitted with gaussian functions. The relative concentrations of chloride were converged to 1.0 after 0.7 hours for S-1, 6.3 hours for S-2, and 389 hours for S-3. Average linear velocity, longitudinal dispersion coefficient, and longitudinal dispersivity were calculated by chloride breakthrough curves. Longitudinal dispersion coefficients were $1.20{\times}10^{-4}\;m^2/sec$ for S-1, $8.87{\times}10^{-7}\;m^2/sec$ for S-2, and $1.94{\times}10^{-9}\;m^2/sec$ for S-3. Peclet numbers calculated by the molecular diffusion coefficient of chloride and the mean grain diameters of soils were $2.59{\times}10^2$ for S-1, $6.27{\times}10^0$ for S-2, and $1.35{\times}10^{-4}$ for S-3. Mechanical dispersion was dominant for the hydrodynamic dispersion mechanism of S-1. Both mechanical dispersion and molecular diffusion were dominant for the hydrodynamic dispersion mechanism of S-2, but mechanical dispersion was ascendant over molecular diffusion. Hydrodynamic dispersion in S-3 was occurred mainly by molecular diffusion. When plotting three soils on the graph of $D_L/D_m$ versus Peclet number produced by Bijeljic and Blunt (2006), the values of $D_L/D_m$ for S-1 and S-2 were more than 2.0 order compared to their graph. S-3 was not plotted on their graph because the Peclet number was as small as $1.35{\times}10^{-4}$.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.6
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• pp.321-327
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• 2005

Ammonia ($NH_3$) volatilization was measured from latex coated urea (LCU) and normal urea treated rice paddy under transplanting rice culture in Milyang in 2002 and 2003. The $NH_3$ volatilization from incubation experiment was significantly related with ammonium-N ($NH_4-N$) concentration and pH in the surface water. The correlation coefficients of $NH_3$ volatilization compared to the $NH_4-N$ and pH in surface water were significantly higher in urea than LCU. The $NH_3$ volatilization from both urea and LCU treatments was not increased in surface water of pH less than 8.0, while $NH_3$ volatilization increased significantly in the surface water of pH over 8.0. The results in the field experiment indicated that $NH_3$ volatilization after top-dressing of urea increased rapidly with increasing $NH_4-N$ concentration in soil and floodwater, and highest from 7 to 10 days after top-dressing. The amount of $NH_3$ volatilized from urea treatment was in the range of $4.9-8.4kg\;N\;ha^{-1}$. The variations of $NH_3$ volatilization in 2002 and 2003 were caused by changed N dynamics due to the different weather conditions such as rainfall and temperature. The amount of $NH_3$ volatilized from LCU treatment was significantly reduced compared to that of urea. The reason for the reduced $NH_3$ volatilization in LCU treatment would be due to the lower concentration of $NH_4-N$ in floodwater. The amount of $NH_3$ volatilized from LCU treated rice paddy was in the range of $1.2-1.8kg\;N\;ha^{-1}$, and the loss of N by ammonia volatilization was 2.0-2.3%. Loss of N by $NH_3$ volatilization with LCU treatment was reduced by 75-79% comparing to urea treatment.

• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.216-227
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• 2008

To understand eutrophication in the upper regions of brackish Lake Sihwa with a limited water exchange, temporal and spatial distributions of pollutants in water and sediment were investigated from March to October in 2005 and 2006. Also, pollution levels of water and sediment were estimated by trophic state index (TSI) and sediment quality guideline (SQG). Total nitrogen (TN), total phosphorus (TP), organic matter (COD), and chlorophyll $\alpha$ (Chl-$\alpha$) concentrations in the surface waters were largely varied temporally and spatially, and the variations were highest in the middle areas where strong halocline was formed. Chl-$\alpha$ concentrations in the middle area were very high in April (>$900\;{\mu}g\;L^{-1}$) when algal blooms (red tides) occurred. The relationships between TN and Chl-$\alpha$ (r=0.31), and TP and Chl-$\alpha$ (r=0.65) indicated that the algal growth was primarily affected by phosphorus rather than nitrogen. The distribution of COD was similar to that of Chl-$\alpha$, indicating that the autochthonous organic matters may be a more important carbon source, especially in the middle areas. The brackish water regions were classified as eutrophic or hypertrophic based on their TSI values ($69{\sim}76$). In addition, the content of nutrients (especially TP) in surface sediments were classified as severe polluted state, except the upper areas. Major causes of the eutrophication observed were probably due to high nutrients loading from watersheds, the phosphorus release from anaerobic sediment, and long retention time by the limited water exchange through the sluice gates.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.351-360
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• 2016

The purpose of this study is to predict visual-spatial working memory performance through the characteristics of an electroencephalogram (EEG) in the resting state. The 31 study participants, middle school students with various to academic performance, were underwent visual-spatial working memory test in the Comprehensive Attention Test (CAT) on December in 2014. Each 7 and 6 participants were divided into an Excellent Working Memory (EWM) group and Poor Working Memory (PWM) group depending on the forward/backward working memory scores. The EEG measurements and analysis of the data from a Brain Function Tester were performed by the two groups. A Mann-Whitney Test was used to examine the statistical differences between them. The activation of high beta (${\beta}H$) at the Fp1 and Fp2 sites in the left and right hemisphere, and that of the low beta (${\beta}L$) in the right hemisphere in the EWM group was significantly higher than that in the PWM group. In conclusion, there is a correlation between the visual-spatial working memory performance and the activation of ${\beta}H$ and ${\beta}L$ in the resting state and a close correlation that of ${\beta}L$ in the right hemisphere in terms of mental activity and faculty. Therefore, the visual-spatial working memory performance can be predicted by the activation of ${\beta}H$ and ${\beta}L$ in the resting state. The activation of EEG can be applied as an assessment tool and provide basis data for visual-spatial working memory performance.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.6
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• pp.987-995
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• 2009

The effects of Kwamaegi on serum lipid profiles and ROS(reactive oxygen spices) generating and scavenging enzyme activities were investigated in rats. The three experimental groups were divided as follows: normal control diet group (NC), 5% naturally prepared and freeze-dried Kwamaegi supplemented diet group (NPK) and 5% chitosan-ascorbate treated and artificially dried (CWDD: Chilly Wind & Dehumidification Drier) Kwamaegi supplemented diets group (CAK). There were no significant differences in weight gain, feed intake, feed efficiency ratio or organs weights per body weight including liver, kidney, heart and spleen among the group. In addition, there were no significant differences in serum triglyceride and total cholesterol contents. The HDL-cholesterol contents of the NC, CAK and NPK groups were 62.00, 36.48 and 78.44 mg/dL while LDL-cholesterol contents were 62.00, 36.48 and 78.44 mg/dL, respectively, which were significantly different. The atherogenic indeces in the experimental groups were 0.62, 1.20 and 0.13, respectively. There were no significant differences in total XOD (xanthine oxidoreductase) activities; however XOD type O activity was higher in the NPK group than un the NC group and in the CAK group XOD type O activity was 21~45% lower compared to NC and NPK groups. SOD (superoxide dismutase) activity was significantly higher in the CAK group than in the NC and NPK groups, while there were no significantly differences in GST (glutathione S-transferrase) activity among the groups. Furthermore, serum ALT activity was higher in the NPK group versus the NC and CAK groups. GSH (glutathione) content was higher and LPO (lipid peroxide) content lower in the CAK group compared to the NC and NPK groups. Forem the above results, we suggest that CA treated and artificially dried Kwamaegi is not only a hygienic product but also has lowering effects on LDL-cholesterol and the atherogenic index together with the lowering of ROS-generating and increasing of ROS-scavenging enzyme activities compared to other natural products.

• The Journal of the Petrological Society of Korea
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• v.27 no.1
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• pp.1-15
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• 2018

The characteristics of the rock cleavage of Jurassic Geochang granite were analysed using the distribution of microcrack lengths and spacings. The length and spacing-cumulative diagrams for the six directions of rock cleavages were arranged in increasing order ($H2{\rightarrow}R1$) on the density (${\rho}$) of microcrack length. The various parameters were extracted through the combination of above two types of diagrams. The evaluation for the six directions of rock cleavages was performed using the four groups (I~IV) of parameters such as (I) intersection angle (${\alpha}-{\beta}$), exponent difference (${\lambda}_S-{\lambda}_L$), length of line (ol and ll'), length ratio (ol/os and ll'/sl'), mean length ((ss'+ll')/2), area of right-angled triangle (${\Delta}oaa_a^{\prime}$ and ${\Delta}obb_a^{\prime}$) and area difference (${\Delta}obb^{\prime}-{\Delta}oaa^{\prime}$ and ${\Delta}obb_a^{\prime}-{\Delta}oaa_a^{\prime}$), (II) length of line (oa and os) and area (${\Delta}oaa^{\prime}$), (III) length of line (sl') and length ratio (ss'/ll') and (IV) length of line (ob, ss' and ls') and area (${\Delta}obb^{\prime}$, ${\Delta}ll^{\prime}s^{\prime}$, ${\Delta}ss^{\prime}l^{\prime}$ and ⏢ll'ss'). The results of correlation analysis between the values of parameters for three rock cleavages and those for three planes are as follows. The values of parameters for three rock cleavages are in orders of (I) H(hardway, (H1 + H2)/2) < G(grain, (G1 + G2)/2) < R(rift, (R1 + R2)/2), (II) R < G < H, (III) G < H < R and (IV) H < G < R. On the contrary, the values of parameters for three planes are in orders of (I) R' < G' < H', (II) H' < G' < R' and (III and IV) R' < H' < G'. Especially the values of parameters belonging to group I and group II show mutual reverse orders. In conclusion, this type of correlation analysis is useful for discriminating three quarrying planes.

• Korean journal of applied entomology
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• v.59 no.3
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• pp.265-275
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• 2020

In this study, we analyzed the nutritional ingredients of drone pupae (16^th to 20^th instar old) to evaluate the value of bee products and provide basic data for product diversification, and the extracts prepared using these pupae were tested for physiological activity. According to the analysis of the general ingredients of the freeze-dried powder of these bee pupae, the moisture, crude protein, crude fat, and crude ash was 1.69 ± 0.07%, 48.52 ± 0.20%, 23.41 ± 0.14%, and 4.05 ± 0.02%, respectively. Vitamin C and vitamin E were 14.92 ± 0.52 mg/100 g and 6.06 ± 0.11 mg α-TE/100 g, respectively. Regarding minerals, the highest content of K (1349.13 ± 34.57 mg/100 g) and P (1323.55 ± 43.85 mg/100 g) was observed and Ca and Fe were 55.43 ± 1.51 mg/100 g and 5.49 ± 0.19 mg/100 g, respectively. The fatty acids of the water extracted freeze-dried pupae powder accounted for approximately 59.62 of saturated fatty acids and 40.38 of unsaturated fatty acids, and high-quality fatty acids such as palmitic acid (C16:0) was 35.49 ± 0.08 and oleic acid (C18:1, n-9) was 35.91 ± 0.22 (g/100 g total fatty acids). The total amino acid content was 38.99 ± 2.63 g/100 g and the free amino acid was a total of 5129.04 mg/100 g, of which 1257.68 mg/100 g was proline and 759.12 mg/100 g glutamic acid. The DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity of the drone pupae extract showed values of 0.8 for distilled water extract, 3.2 for 50% EtOH extract, 6.4 for 70% EtOH extract, and approximately 90% for 32 ㎍/mL for 100% EtOH extract. These results suggest that the main compound contributing to the antioxidant activity is a polar compound, and it is highly likely to be a low-molecular protein or a free amino acid. In conclusion, the honey bee drone pupa is excellent as a food resource and can be utilized as a new functional material for food and functional food.

• Journal of Nutrition and Health
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• v.51 no.6
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• pp.556-566
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• 2018

Purpose: This study was designed to determine the relationship between health behaviors and high levels of low-density lipoprotein-cholesterol (LDL-cholesterol) according to cardiovascular risk factors among Korean adults. Methods: This cross-sectional study was based on the sixth Korea national health and nutrition examination survey (KNHANES VI). Participants were 13,841 adults aged 19 years and older. Cardiovascular risk factors were stroke, myocardial infarction or angina, diabetes mellitus, smoking, hypertension, aging, high density lipoprotein-cholesterol (HDL-cholesterol) under 40 mg/dL and HDL-cholesterol over 60 mg/dL. Cardiovascular risk groups were classified as very high risk (stroke, myocardial infarction or angina), high risk (diabetes mellitus), moderate risk (over 2 risk factors), and low risk (below 1 risk factor). The prevalence of high LDL-cholesterol was calculated using the LDL-cholesterol target level according to cardiovascular risk group. Results: The prevalence of high LDL-cholesterol was 25.5% in males and 21.7% in females. Complex sample cross tabulation demonstrated that the high LDL-cholesterol and normal groups differed significantly according to age, education, body mass index, percentage of energy from carbohydrate, fat, saturated fat and n-6 in males and females. These two groups were also significantly different according to smoking in males and the percentage of energy from n-3 in females. Complex sample multiple logistic regression analysis adjusted for multiple confounding factors demonstrated that the probability of high LDL-cholesterol was significantly associated with current smoking (OR: 1.66, 95% CI: 1.40-1.99), obesity (OR: 1.95, 95% CI: 1.64-2.31) in males, and current smoking (OR: 1.73, 95% CI: 1.19-2.52), obesity (OR: 1.63, 95% CI: 1.39-1.90), percentage of energy from n-3 (quartile 1 vs. quartile 2; OR: 0.77, 95% CI: 0.62-0.96; quartile 1 vs. quartile 3; OR: 0.73, 95% CI: 0.56-0.94; quartile 1 vs. quartile 4: OR: 0.67, 95% CI: 0.51-0.87) in females. Conclusion: This study reveals the impact of smoking, obesity, energy percentage of nutrient intake on LDL-cholesterol.

• The Journal of the Petrological Society of Korea
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• v.28 no.1
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• pp.1-13
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• 2019

The characteristics of the rock cleavage of Jurassic Geochang granite were analysed using the parameters from the length and spacing-cumulative frequency diagrams. The evaluation for three planes and three rock cleavages was performed using the 25 parameters such as (1~2) slope angle(${\alpha}^{\circ}$and ${\beta}^{\circ}$), (3) intersection angle(${\alpha}-{\beta}^{\circ}$), (4) exponent difference(${\lambda}_S-{\lambda}_L$), (5~12) length of line(oa, ob, ol, os, ss', ll' and sl') and (13~15) length ratio(ol/os, ss'/ll' and ll'/sl'), (16) mean length((ss'+ll')/2), (17~23) area (${\Delta}oaa^{\prime}$, ${\Delta}obb^{\prime}$, ${\Delta}obb^{\prime}$, ${\Delta}oaa_a^{\prime}$, ${\Delta}obb_a^{\prime}$, ${\Delta}ll^{\prime}s^{\prime}$, ${\Delta}ss^{\prime}l^{\prime}$ and ⏢$ll^{\prime}ss^{\prime}$) and (24~25) area difference(${\Delta}obb^{\prime}-{\Delta}oaa^{\prime}$ and ${\Delta}obb_a^{\prime}-{\Delta}oaa_a^{\prime}$). Firstly, the values of the 11 parameters(group I: No. 1, 3~4, 7, 9~10, 13, 15~16, 20 and 25), the 3 parameters(group II: No. 5, 8 and 17) and the 2 parameters(group III: No. 12 and 22) are in orders of H(hardway) < G(grain) < R(rift), R < G < H and G < H < R, respectively. On the contrary, the values of parameters belonging to the above three groups show reverse orders for three planes. Secondly, the generalized chart for three planes and three rock cleavages were made. From the related chart, the distribution types formed by the two diagrams related to lengths and spacings were derived. The diagrams related to spacings show upward curvature in the chart of rift plane(G1 & H1, R') and hardway(H1 & H2, H). On the contrary, the diagrams related to lengths show downward curvature. These two diagrams take the form of a convex lens in the upper section. Besides, the two diagrams cross each other in the lower section. The overall shape formed by the above two diagrams between three planes($H^{\prime}{\rightarrow}G^{\prime}{\rightarrow}R^{\prime}$) and three rock cleavages($R{\rightarrow}G{\rightarrow}H$) display in reverse order. Lastly, these types of correlation analysis is useful for discriminating three quarrying planes.