• Korean Journal of Soil Science and Fertilizer
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• v.20 no.1
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• pp.29-34
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• 1987

This experiment was designed to find out the effects of soil conditioner, Polyacrylamide (PAM) and Bitumen, on the changes of soil aggregate properties and crop yields. The soil conditioners were treated at the rates of 0.5% and 1% to sandy loam and silty clay loam soils. The aggregate stability, wetting angle, mean weight diameter and air permeability were analyzed. Pot experiments were carried out to investigate the soybean growths and soil property changes after the soil conditioners were sprayed to surface soils. Soil aggregate stability was increased remarkably by the soil conditioner, PAM and Bitumen, treatments. PAM was more effective in sandy loam than silty clay loam, but Bitumen was better in silty clay loam. Wetting angle of the soil was changed slightly by PAM treatment, but it was greatly changed to hydrophobic by Bitumen treatment. Air permeability, water infiltration rate and moisture retention of the soils were increased by surface application of soil conditioners, PAM and Bitumen. The growths of soybean in conditioner applicated pots were better than those of untreated pots from early stage, and the yields were increased 6-13%.

• Research in Plant Disease
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• v.8 no.1
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• pp.55-58
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• 2002

In July 2001, rotting and shivering flowers of cotton rose (Hibiscus mutabitis) were fecund in the flower beds along the roadsides in Jinju area. The disease first started as water-soaking, dark-green lesions on the petals, and then whole flower was rotted rapidly, Whitish mycelia and monosporous sporangiophore with monosporous sporangiola were formed abundantly on the lesions. Colony appeared as white to pale yellowish brown mycelia on potato dextrose agar medium (PDA). Monosporous sporangiophore was long slender and branched at the apex, each branch bearing a head of sporangiospores. Sporangium was subglobose in shape and was 42.6-114.2$\mu$m in size. Monosporous sporangiola were elliptic, fusiform or ovoid, and brown in color and 12.3~21.6 $\times$8.3~11.6$\mu$m Um in size. Sporangiospores were elliptic, fusiform or ovoid in shape, dark brown or brown in color and 16.3~23.8$\times$8.2~13.6$\mu$m in size, and they had three or more appendages at bipolar end. Zygospores were mostly globose, dark black colored and sized was 46.2-78.4$\mu$min diameter, The fungus grew on PDA between at 15 to 4$0^{\circ}C$, and the optimum temperature was 3$0^{\circ}C$. This is the first report on the flower rot of cotton rose caused by C. cucurbitarum in Korea.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.364-370
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• 2014

The nutrient and irrigation management of scion and rootstock can alleviate stress on grafted transplants after grafting and promote the growth. This study investigated the effects of nutrient and irrigation management of scion and rootstock on the graft-take and growth of grafted pepper transplants. Before grafting, the scions were subjected to different water potential regimes in media by controlling the irrigation frequency and time. The scions were subirrigated 0, 1(two days before grafting), 1(one days before grafting) or 2 times for five days before grafting. The irrigation frequency and time influenced the water potential of media and the growth of scion and grafted transplants. At 13 days after grafting, fresh and dry weight of transplants which were irrigated once at two days before grafting were greater by 29 and 34% than those without irrigation during five days before grafting. This suggests that mild water stress on scion prior to grafting by controlling water management alleviate water stress on grafted transplants after grafting and improve the growth. Before grafting, the rootstocks were subjected to different nutrient regimes by controlling nutrient solution application. The rootstocks were supplied with nutrient solution 0, 1, 2, or 4 times. The nutrient application frequency and time influenced the electrical conductivity (EC) and pH of media. Accordingly, the growth and mineral contents of rootstock and grafted transplants were also affected. At 13 days after grafting, fresh and dry weight of transplants with four times of nutrient application increased by 30 and 20%, respectively, than those without nutrient solution supply during seven days before grafting. Therefore, it is recommended that nutrient solution be supplied more than four times during seven days before grafting for the production of high quality transplants.

• Journal of the Korean Society of Food Culture
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• v.13 no.4
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• pp.293-305
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• 1998

According to economical status, under-nutrition and over-nutrition coexist in preschool children in Korea. Subjects consumed more than RDA in most nutrients, and children in of the upper income class tended to have more nutrients than those of the low income class. Especially in case of energy, protein, fat, vitamin $B_2$, and P there were significant differences among the different classes. The mean calorie compositions of carbohydrates, protein and fat were $57{\sim}59:\;16{\sim}17:\;26{\sim}27$ and fat calorie percentage was higher than quantity recommended for Korean adults. Energy, protein, Fe, vitamin A, $B_1$ and C intakes were taken mostly from plant food sources. In the upper income class group, intakes of protein and vitamin $B_2$ from animal food sources were higher than in any other income classes. Intakes of iron, vitamin A, $B_1$ and C were largely provided by plant food group. Especially 44-45% of vitamin A were taken from vegetable and fruits group, which indicated that about 50% of vitamin A intake was the form of ${\beta}-carotene$. Also compared with other groups, in the upper income class group, the intakes of energy, protein, Ca, p, vitamin $B_1$ and vitamin $B_2$ from cereal and potatoes were significantly lower, and those of Ca and P from milks and meats, fishes & eggs were significantly higher(p<0.05). The mean fat intake in all subjects was $38{\sim}43g/day$. Regardless of income class, oleic acid($6.6{\sim}8.4g$) and linoleic acid($6.7{\sim}8.1g$) were the most abundant fatty acids contained in the diet. The upper class group consumed significantly more total saturated fatty acids and total monounsaturated fatty acids(p<0.05). In polyunsaturated fatty acids, there were no differences between 3 different income classes, but intakes of total ${\omega}6$ fatty acids in the upper class tended to be higher and those of total o3 fatty acids in low class tended to be higher. Therefore, ${\omega}6/{\omega}3$ tended to be higher in the upper class group. Regardless of income classes, P/M/S and ${\omega}6/{\omega}3$ ratios in all subjects were $0.9{\sim}l.3/1.0{\sim}1.1/1.0$ and $5.2{\sim}7.4/1.0$, respectively and were in a desirable range. Cholesterol intake of subject was 184-218 mg/day, which was comparable to the value of Korean adult intake.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.654-666
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• 2018

This study was determined the effects of dietary omega-6 and 3 fatty acid ratios (n-6/n-3, 0, 4:1, 15:1, 30:1) on lipid metabolism in obese model animal rats. Blood triacylglycerol, total cholesterol, LDL-C, glucose, ALT, AST, insulin, and leptin concentrations in n-6/n-3 group were decreased by 22.21, 20.60, 52.96, 15.71, 11.97, 9.13, 37.57, 45.98%, respectively, while HDL-C and phospholipid concentrations were increased by 28.38, 80.39% respectively, compared with control group, as especially in 4:1 group showed the greatest effect. SREPB-$1{\alpha}$ and SREPB-2 mRNA in liver tissues were down-regulated in n-6/n-3 group, but LPL-mRNA of PPARs in adipose tissue was up-regulated compared with control group. The adipocyte size in liver tissues was decreased in the order of n-6/n-3 ratio of 30:1, control, 15:1 groups, and the adipocyte size in adipose tissues was decreased in the order of n-6/n-3 ratio of control, 30:1, 15:1, 4:1 groups.

• Journal of Advanced Navigation Technology
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• v.15 no.2
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• pp.213-220
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• 2011

In this paper, the channel preprocessor with an area-efficient architecture is proposed for the MIMO symbol detector which can support four transmit and receive antennas. The proposed channel preprocessor can shrink the channel dimension to reduce the hardware complexity of the MIMO symbol detector. Also, the proposed channel preprocessor is implemented with very low complexity by using QR decomposition (QRD) and log-number system (LNS). By applying QRD and LNS to the nulling matrix calculation block, the numbers of matrix-multiplications and matrix-divisions are decreased and thus the complexity of the proposed channel preprocessor is significantly reduced. The proposed channel preprocessor was designed in a hardware description language (HDL) and synthesized to gate-level circuits using 0.13um CMOS standard cell library. With the proposed channel preprocessor, the number of logic gates for channel preprocessor is reduced by 20.2% compared with the conventional architecture.

• Journal of the Mineralogical Society of Korea
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• v.22 no.2
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• pp.129-138
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• 2009

The XRF core scanner was used, to analyze high resolution chemical elements in deep sea sediment cores from Clarion-Clipperton fracture zone of the northeastern Pacific. Comparison of data estimated by the XRF core scanner with ICP-AES showed relatively weak correlation coefficients between elements (especially Ba, Pb, Sr, Zr) except for Mn contents ($r^2$ > 0.89). However down-core variations of most elements seemed to be well matched each other and furthermore, XRF core scanner data reflected changes of sedimentary facies characterized by sediment colors. Mn/Al ratio dramatically changed at boundaries of facies in BC08-02-05 and BC08-02-13 but progressive changes occured in BC08-02-02, BC08-02-09 and BC08-02-10 where the sediments have been affected by bioturbations. The difference of Mn/Al ratio in each facies (Facies I, Facies II, Facies III) has been caused by redox condition of depositional environment. Vertical change of Mn/Al ratio were divided into two types probably affected by activities of benthic organisms in the study area.

• Advances in Traditional Medicine
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• v.4 no.2
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• pp.104-111
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• 2004

Sasang Constitutional Medicine is a major branch of Korean Traditional Oriental Medicine. The differences of disease susceptibility to be shown in Sasang constitution may be due to genetic factors. Therefore, we examined interrelationship among cerebral infarction (CI), apolipoprotein E (apoE) gene polymorphism, and Sasang constitutional classification. ApoE is a key protein modulating the highly atherogenic apoB containing lipoproteins and is a candidate gene for the development of coronary artery disease (CAD). The ${\varepsilon}2\;and/or\;{\varepsilon}4$ alleles were the first to be implicated in premature CAD, which resulted in this polymorphism being extensively studied. We investigated the association between apoE genotype and CI by case-control study in a Korean population. We also classified CI patients and control group into groups according to Sasang Constitutional Medicine. 196 CI patients and 379 controls without CI were examined. ApoE genotype was determined by 8% polyacrylamide gel separation after DNA amplification. A significant difference in the apoE genotype distribution was observed in the CI patients compared with that in controls ($X^{2}$=14.920, df=4, P=0.005). Also, the frequency of Taeumin constitution in patients with CI was significantly higher than that in controls (58.0% vs. 36.9%; P<0.001). However, the Taeumin constitution did not enhance the relative risk for CI in the subjects with apoE ${\varepsilon}2\;and/or\;{\varepsilon}4$ alleles. No differences in the apoE genotypes frequencies were observed in the Taeumin compared with that in the other constitutions. In addition, we investigated whether the DD genotype of angiotensin converting enzyme (ACE) gene, a candidate gene for CI, was associated with CI, Taeumin constitution, and apoE polymorphism. As a result, the frequency of Taeumin constitution was significantly higher in CI patients with both apoE ${\varepsilon}3/{\varepsilon}4$ and ACE ID/DD genotypes than in the remaining Sasang constitutions (14.5% vs. 8.3% and 0%) ($X^{2}$=13.521, df=6, P=0.035). In summary, we concluded that the apoE polymorphism is a major risk factor for CI in Koreans and the ACE ID/DD genotype enhanced the relative risk for CI in the subjects with apoE ${\varepsilon}3/{\varepsilon}4$ genotype and Taeumin constitution.

• Journal of Dental Rehabilitation and Applied Science
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• v.20 no.2
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• pp.135-141
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• 2004

Statement of problem: Arrangement and angulation of clinical crown is very important for esthetic restoration in the upper anterior dentition. However, there was no clinical criteria to mesial angulation of the crown for Korean. Purpose: This study was undertaken to estimate the mesial angulation of the crown of the anterior teeth and the Oh's E-triangle made of the inter-pupillary line and the mesial inclination lines of the canines. Material and Method: 270 portraits of Korean were used for this study. The mesial angulation of the upper anterior teeth and the relationship of the inter-pupillary line and the mesial inclination lines of the canines were measured with the tools of PhotoShop software on the scanned images. Results: The angulation between the clinical crowns having a same name in the upper anterior dentition were $3.6^{\circ}$ between the central incisors, $8.6^{\circ}$ between the lateral incisors, and $13.6^{\circ}$ between the canines. There was no significance according to occupation and gender( P > 0.05). The ratio of height to base line of Oh's E-triangle was 4.47. 81.6% of the subjects showed the mesial inclination line of the canine passed by mesial border area of pupil. Conclusion: These data for Korean would be useful clinically to give the esthetic arrangement and to make the contour of upper anterior teeth.

• Journal of IKEEE
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• v.7 no.1 s.12
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• pp.72-79
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• 2003

Classical designs of optical transimpedance preamplifier for p-i-n photodiode receiver circuits generally employ common source transimpedance input stages. In this paper, we explore the design of a class of current-mode optical transimpedance preamplifier based upon common gate input stages. A feature of current-mode optical transimpedance preamplifier is high gain and high bandwidth. The bandwidth of the transimpedance preamplifier can also be increased by the capacitive peaking technique. In this paper we included the development and application of a circuit analysis technique based on the minimum noise. We develop a general formulation of the technique, illustrate its use on a number of circuit examples, and apply it to the design and optimization of the low-noise transimpedance amplifier. Using the noise minimization method and the capacitive peaking technique we designed a transimpedance preamplifier with low noise, high-speed current-mode transimpedance preamplifier with a 1.57GHz bandwidth, and a 2.34K transimpedance gain, a 470nA input noise current. The proposed preamplifier consumes 16.84mW from a 3.3V power supply.