• Journal of the Korean Dietetic Association
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• v.18 no.2
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• pp.97-114
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• 2012

This study was performed to assess the nutritional status and hair mineral content of children with behavioral problems and compare the values with a gender, age-matched control group. The subjects were recruited from S elementary school children in Seoul, Korea. Students scored higher than 60 points were diagnosed with behavioral problems according to the Korean-Child Behavior Checklist. Nutritional assessment of the two groups (behavior problem group: male n=15, female n=24; $9.6{\pm}1.6$ years, control group: male n=16, female n=18; $9.5{\pm}1.9$ years) was performed using a nutritional survey and by measuring hair mineral contents. In the results, food frequency questionnaire analysis showed that the intakes of anchovy (P<0.05), soybean curb (P<0.01), radish (P<0.05), bean sprouts (P<0.05), spinach (P<0.05), carrot (P<0.05), pumpkin (P<0.05), lettuce (P<0.05), cabbage (P<0.01), apple (P<0.05), and milk (P<0.01) were higher in the control group than the behavior problem group, whereas intakes of ramyeon (P<0.05), cookies (P<0.05), and coke (P<0.01) were higher in the behavior problem group than the control group. Intakes of most nutrients such as plant-derived protein (P<0.05), fiber (P<0.05), plant-derived calcium (P<0.05), phosphorus (P<0.05), plant-derived iron (P<0.05), vitamin B2 (P<0.05), vitamin B6 (P<0.05), vitamin C (P<0.01), vitamin E (P<0.05), and folate (P<0.05) were significantly higher in the control group than the behavior problem group. Hair analysis showed that the levels of arsenic (P<0.05), mercury (P<0.001), uranium (P<0.05), iron (P<0.001), boron (P<0.01), and germanium (P<0.001) were lower, but the levels of phosphate (P<0.05), chromium (P<0.001), sodium (P<0.05), and sulfur (P<0.001) were higher in the behavior problem group than the control group. Conclusively, behavioral problems constitute a complicated condition in which nutritional factors may play major roles. However, it is still under investigation as to whether or not modification of dietary habits or nutritional supplementation can improve children's behavior, since symptoms require a broad understanding of the environmental and genetic interactions.

• Journal of the Korean Ceramic Society
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• v.39 no.9
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• pp.896-901
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• 2002

Since many process parameters of FHD(Flame Hydrolysis Deposition) are involved in forming multi-component amorphous silica film ($SiO_2-B_2O_3-P_2O_5-GeO_2$), it has not been easy to predict the optical, mechanical and thermal properties of deposited film from the simple process parameters, such as source flow rate. Furthermore, the prediction of final composition of film becomes even more difficult after sintering at high temperature due to the evaporation of volatile dopants. The motivation of the study was to clarify the quantitative relationship between simple process parameters such as the flow rate of source gases and resulting chemical composition of sintered film. Hence, the compositional analysis of silica soot by FTIR(Fourier Transformation Infrared Spectroscopy) and ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectrometry) under the control of the amount of dopant was carried out to obtain the quantitative composition. By measuring spectrum of absorbance from FTIR, the compositional change of B-O, Si-O, OH($H_2O$) in silica film was measured. The concentrations of these dopants were also measured by ICP-AES, which were compared with the FTIR result. The final quantitative relationship between simple process parameters and composition was deduced from the comparison between two results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1281-1286
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• 2006

We have used the silicon-carbide(4H-SiC) instead of conventional silicon materials to develope of the planar junction barrier schottky rectifier for ultra high breakdown voltage(1,200 V grade). The substrate size is 2 inch wafer, Its concentration is $3*10^{18}/cm^{3}$ of $n^{+}-$type, thickness of epitaxial layer $12{\mu}m$ conentration is $5*10^{15}cm^{-3}$ of n-type. The fabticated devices are junction barrier schottky rectifier, The guard ring for improvement of breakdown voltage is designed by the box-like impurity of boron, the width and space of guard ring was designed by variation. The contact metals to rectify were used by the $Ni(3,000\:{\AA})/Au(2,000\:{\AA})$. As a results, the on-state voltage is 1.26 V, on-state resistance is $45m{\Omega}/cm^{3}$, maximum value of improved reverse breakdown voltage is 1180V, reverse leakage current density is $2.26*10^{-5}A/CM^{3}$. We had improved the measureme nt results of the electrical parameters.

• Journal of Radiation Protection and Research
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• v.22 no.2
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• pp.77-83
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• 1997

Epoxy resin-type neutron shielding materials, KNS(Kaeri Neutron Shield)-101, KNS-102, and KNS-103 have been fabricated to be used in spent fuel shipping cask. The base material is epoxy resin, and polypropylene, aluminium hydroxide, and boron carbide are added. These shielding materials offer good fluidity at processing, which makes it possible to apply this resin shield to complicated geometric shapes such as shipping cask. The shielding property of these shielding materials for shipping cask for loading 28 PWR spent fuel assemblies has been evaluated. ANISN code is used to evaluate the shielding property of the shipping cask with the thickness of the three neutron shielding materials greater than 10 cm. As a result of analysis, the maximum calculated dose rate at the radial surface of the cask is determined to be $300{\mu}Sv/h$ and the maximum calculated dose rate at 100 cm from the cask is $97{\mu}Sv/h$. These dose rates remain within allowable values specified in related regulations.

• Journal of Sericultural and Entomological Science
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• v.27 no.1
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• pp.12-17
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• 1985

soil survey and chemical analysis on mulberry nursery garden were carried out to study the causes of the non-sprouting phenomenon occured seriously in Buy and Ogchun in 1983 and Sangju in 1984. In addition, 115 nursery garden soils taken from 21 sapling produsers in Chungbuk province were analyzed in 1984. The results were as follows, 1. Symptom of dead saplings was the highest in boron deficiency by 59% and the lowest in rot symptom. The rest of saplings by 34.9% were not detected any symptom. 2. The nursery gardens showen non-sprouting phonomenon were located along the stream. As the result, soil depth was shallow, around 20cm deep and subsoil composed with coarse sand and gravels. 3. Nursery soils were mostly strong acid, low in Ca and Mg content, especially B, whereas available phosphorus and potassium were abundant at some gardens, and deficient at others. 4. Application of red earth or borax to nursery garden, especially to paddy, increased sprouting rate. 5. Paddy nursery garden occupied by 52.8% of 60.8ha of total garden area in Chungbuk province. Ninty point five percent of the nursery garden was lower in pH than 6.5, 87.0% lower in K than 0.5me/100g, 40.8% lower in Ca than 6.5me/100g, 94.8% lower in Mg the 2.00me/100g 99.1% lower in B than 0.3ppm.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.2
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• pp.65-70
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• 1976

The effect of leaf spray ($80{\ell}$ of 100 times diluted solution per 10a) of three liquid complex fertilizers (Compresal 1 and 2. and 3P) on rice (var, Minehikari) at 10 days before and after heading and 20 days after heading in a farmer's field was investigated by yield components and flag leaf analysis. 1. Leaf spray significantly increased filled grain ratio (at 10% level) and harvest index (at 5% level) suggesting significant yeild increase in uniform field condition. 2. Phosphorus content of flag leaf was in deficient range and increased by leaf spray while iron content was decreased indicating that liquid complex fertilizer supplied phosphorus which ratards iron translocation to the upper leaves. 3. Higher manganese content in flag leaf by leaf spray (significant at 5% level) suggests that phosphorus stimulates manganese translocation to the upper leaves resulting in favorable Fe/Mn balance. 4. Nitrogen concentration in flag leaf was in the insufficient range suggesting that nitrogen in liquid complex fertilzer had to be a nitrogen supply source. 5. In flag leaf calcium concentration was increased by leaf spray but that of boron and zinc was decreased.

• Textile Coloration and Finishing
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• v.28 no.1
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• pp.48-56
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• 2016

Improvement of heat sink technology related to the continuous implementation performance and extension of device-life in circumstance of easy heating and more compact space has been becoming more important issue as multi-functional integration and miniaturization trend of electronic gadgets and products has been generalized. In this study, it purposed to minimize of decline of the heat diffusivity by gluing polymer through compounding of inorganic particles which have thermal conductive properties. We used NH-9300 as base resin and used inorganic fillers such as silicon carbide(SiC), aluminum nitride(AlN), and boron nitride(BN) to improve heat diffusivity. After making film which was made from 100 part of acrylic resin mixed hardener(1.0 part more or less) with inorganic particles. The film was matured at $80^{\circ}C$ for 24h. Diffusivity were tested according to sorts of particles and density of particles as well as size and structure of particle to improve the effect of heat sink in view of morphology assessing diffusivity by LFA(Netzsch/LFA 447 Nano Flash) and adhesion strength by UTM(Universal Testing Machine). The correlation between diffusivity of pure inorganic particles and composite as well as the relation between density and morphology of inorganic particles has been studied. The study related morphology showed that globular type had superior diffusivity at low density of 25% but on the contarary globular type was inferior to non-globular type at high density of 80%.

• Progress in Superconductivity and Cryogenics
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• v.18 no.4
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• pp.9-14
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• 2016

The effect of the size and shape of magnesium(Mg) powder on the formation of $MgB_2$ and the critical current density($J_{c,}$) of $MgB_2$ bulk was studied. As a precursor for the formation of $MgB_2$, Mg and $MgB_4$ powder, which was synthesized through the reaction of boron (B) with Mg powders, was used. $MgB_4$ was mixed with Mg powders of various sizes, pressed into pellets and heat-treated at $650^{\circ}C-750^{\circ}C$ in flowing argon gas. The XRD analysis of the heat-treated $MgB_2$ samples showed that the volume fraction of $MgB_2$ was the highest as 92.74 % when spherical Mg powder with an average size of $25.7{\mu}m$ was used, whereas the volume fraction was the lowest as 79.64 % when plate-like Mg powder with a size of $34.1{\mu}m$ was used. The superconducting transition temperature ($T_c$) of $MgB_2$ was not sensitive to the characteristics of the Mg powders used. All of the prepared $MgB_2$ samples showed a high $T_c$ of 38.3 K and a small superconducting transition width of 0.2 K-0.5 K. $J_c$ (5 K and 1 T) of $MgB_2$ was the highest as $3.93{\times}10^4A/cm^2$ when spherical Mg powder with a size of $25.7{\mu}m$ was used, whereas $J_c$ was the lowest as $2.18{\times}10^4A/cm^2$when plate-like Mg powder with a size of $34.1{\mu}m$ was used. The relationship between the $J_c$ of $MgB_2$ and the characteristics of the Mg powders used was explained in terms of the volume fraction of $MgB_2$ and the apparent density of the $MgB_2$ pellets.

• Journal of the Korean Vacuum Society
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• v.17 no.2
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• pp.160-164
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• 2008

The Characterization of $MgB_2$ Thin Film by Slow Positron Annihilation Spectroscopy Enhance signal-to-noise ratio, slow positron coincidence Doppler Broadening method has been applied to study of characteristics of $MgB_2$ superconductor film, which were performed at 30 K and 50 K sample temperature near Tc of it. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The S-parameter values were increased then decreased while the positron implantation energies were increasing, that indicated the diffusion into the samples. The S-parameters of the anisotropic 1 ${\mu}m$ $MgB_2$ thin film which were implanted by positrons at 10 keV are 0.567 at 30 K and 0.570 at 50 K. It is believed that the positrons annihilate with normal-electrons instead of super-electrons in the $MgB_2$ superconductor.

• Horticultural Science & Technology
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• v.35 no.3
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• pp.289-299
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• 2017

The objective of this study was to determine the effect of replacing perlite (PL) with pellets processed with poultry feather fiber as an inert material to prepare growing medium. The growth and flowering of Salvia splendens 'Vista Red' grown in individual growing medium $Biosangto^{(R)}$, peat moss (PM), PL, and two pellets (P45-1 and P45-2) were evaluated. Peat moss was mixed with PL, P45-1, or P45-2 at various ratios (1:0 to 1:3 or 3:1 by volume) to investigate the feasibility of replacing PL with pellets. Nutrient composition of the growing medium and leaf tissues was analyzed. The number of florets, inflorescence length, plant height, and fresh weight of plants grown in media containing P45-1 or P45-2 were reduced compared to those grown in individual growing medium PM or PL. As the mixing ratio of P45-1 or P45-2 to PM was higher, the growth of salvia, such as inflorescence length, plant height, number of leaves, and fresh weight was inhibited. Our results indicate that mixing three parts PM with one part of P45-1 (PM/P45-1/3:1) or P45-2 (PM/P45-2/3:1) accelerated flowering and increased the number of florets and leaves compared to other mixing ratios of PM and pellets media. The concentrations of phosphorus (P), calcium (Ca), boron (B), iron (Fe), and copper (Cu) in individual growing medium PL, P45-1, and P45-2 were significantly lower than those in PM. The concentration of N was the highest in leaves of plants grown in P45-1 or P45-2 amended media, and the concentrations of P, Ca, and zinc (Zn) in leaves were lower in individual growing medium P45-1 or P45-2 than in PM and PL. The pH of PM/P45-1/3:1 or PM/P45-2/3:1 media was maintained at optimal level (5.8-5.9) and the concentrations of macro- and micro-elements in the media and leaves were considered to be optimal levels. Therefore, mixing three parts PM with one part P45-1(PM:P45-1/3:1) or P45-2 (PM:P45-2/3:1) is recommended for improved growth and flowering in salvia. This suggests that P45-1 or P45-2 can replace PL as an inert material to prepare growing medium.