• Journal of radiological science and technology
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• v.39 no.4
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• pp.501-507
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• 2016

This study is to figure out the amount of primary X-ray generated in SID 50cm, 1m, and 2m penetrating protective aprons in X-ray radiography for hands, skull, and lumbar spine. Results are as follows: Firstly, the exposure dose of primary X-ray which is low such as that of hand X-ray may be reduced by 270 times if protective aprons are worn, but it still slightly penetrates 0.3mm thick Pb protective aprons at SID 50cm, 1m, and 2m. Secondly, the exposure dose of primary X-ray which is moderate such as that of skull X-ray may be reduced by 22 times if protective aprons are worn, but it still fairly penetrates 0.3mm thick Pb protective aprons at SID 50cm, 1m, and 2m. Thirdly, the exposure dose of primary X-ray which is very high such as that of lumbar spine X-ray may be reduced by 13 times if protective aprons are worn, but it still penetrates a lot 0.3mm thick Pb protective aprons at SID 50cm, 1m, and 2m. Therefore, people in X-ray room should not only wear protective aprons at any spaces that the primary X-ray can reach, but also need to stand behind the thick Pb shield to protect the body if it is inevitable to stay in the room.

• Korean Journal of Environment and Ecology
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• v.24 no.2
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• pp.178-185
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• 2010

The purpose of this study is to verify the effectiveness of the biotope model in applying and developing Korean urban forests. We found that there are 17 biotope assessment indicators, including forest layer structure, site conditions, ratio of broad-leaved trees, species richness, etc. In terms of correlation analysis between indicators, the stand ages and the period of space formation have the highest relativity(coefficient 0.684). On the other hand, indicators that have negative relativity are layer structure and risk, with a coefficient of -0.412. Ten models were developed for the multiple regression analysis. 10 variables(site conditions(X2), ratio of broad-leaved trees(X3) and so forth except layer structure(X1), species richness(X4)) were found to have a 95% significance level The results from comparing the regression model and adding-up estimation matrix, the most accurate one was Model 3, which has a 91.7% out of the 10 models. However more monitoring will be needed to improve the accuracy of models for the Korean urban forests in future.

• Korean Journal of Materials Research
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• v.32 no.11
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• pp.481-488
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• 2022

The Cu₂ZnSn(S_xSe_1-x)₄ (CZTSSe) absorbers are promising thin film solar cells (TFSCs) materials, to replace existing Cu(In,Ga)Se₂ (CIGS) and CdTe photovoltaic technology. However, the best reported efficiency for a CZTSSe device, of 13.6 %, is still too low for commercial use. Recently, partially replacing the Zn²⁺ element with a Cd²⁺element has attracting attention as one of the promising strategies for improving the photovoltaic characteristics of the CZTSSe TFSCs. Cd²⁺ elements are known to improve the grain size of the CZTSSe absorber thin films and improve optoelectronic properties by suppressing potential defects, causing short-circuit current (J_sc) loss. In this study, the structural, compositional, and morphological characteristics of CZTSSe and CZCTSSe thin films were investigated using X-ray diffraction (XRD), X-ray fluorescence spectrometer (XRF), and Field-emission scanning electron microscopy (FE-SEM), respectively. The FE-SEM images revealed that the grain size improved with increasing Cd²⁺ alloying in the CZTSSe thin films. Moreover, there was a slight decrease in small grain distribution as well as voids near the CZTSSe/Mo interface after Cd²⁺ alloying. The solar cells prepared using the most promising CZTSSe absorber thin films with Cd²⁺ alloying (8 min. 30 sec.) exhibited a power conversion efficiency (PCE) of 9.33 %, J_sc of 34.0 mA/cm², and fill factor (FF) of 62.7 %, respectively.

• Korean Journal of Materials Research
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• v.4 no.8
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• pp.870-876
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• 1994

In order to investigate the growth behavior of $Y_{2}Ba_{1}Cu_{1}O_{5}$(211) particles in $Y_{1}Ba_{2}Cu_{3}O_{7-\delta}$(123), 123 samples were quenched in air after heat treatment on polycrystal and single crystal MgO substrates at $1100^{\circ}C$ for various periods. 211 grains grew with the increase in holding time. The growth of 211 grains was faster on the polycrystal MgO substrate than on the single crystal MgO substrate. In the samples with the compositions of 211+xCuO($0.2\le X \le 0.8$), the growth rate of 211 grains increased with the increase in CuO content. In the sample with x=0.6 the largest 211 grains were observed. 211 grains in the $Y_{2}Ba_{1}Cu_{1.8}Sn_{0.1}O_{5+\delta}$ samples were distributed very finely and homogeneously. The retarding effect of $SnO_2$ addition on the growth of 211 grain appeared more pronounced in a CuO melt than in a $BaCuO_{2}$+ CuO melt.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.278-284
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• 1990

A study relating the soluble-solids (S.S.) contents of Chinese cabbages to the final titratable acidities(TA) of kimchis was conducted. The S.S. contents of Spring-sowed Chinese cabbages were in the range from $1.20-3.40^{\circ}$ Brix while those of Autumn-sowed Chinese cabbages were in the range from $3.8-6.6^{\circ}$ Brix. The S.S. contents of Chinese cabbages were varing depending on their varieties and the cultivating seasons. However, seasonal variations were much more significant than the varietal variations. The final TAs of kimchis after complete fermentation were found to be directly proportional to the S.S. contents(x) of Chinese cabbages, showing that TA equals to 0.30x+07779. From the equation, a Chinese cabbage of a S.S. content with up to $0.02^{\circ}$ Brix, which is practically impossible to obtain, will make a kimchi which will not be overacidified during the prolonged storage period without any preservative measures.

• Journal of the Korean Chemical Society
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• v.31 no.6
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• pp.491-497
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• 1987

$ThO_2-Tm_2O_3$ (TDT) solid solutions containing 1,3,5,8,10, and 15 mol% $Tm_2O_3$ were synthesized from spectroscopically pure $ThO_2$ and $Tm_2O_3$ polycrystalline powders. The TDT solid solutions were indentified to the fluorite structure by the X-ray powder technique. The values of the lattice parameter were decreased with increasing amount of $Tm_2O_3$ incorporated. But, there was no linearity for the samples containing 8, 10, and 15 mol% $Tm_2O_3$. It was concluded that these samples became incomplete solid solutions. From the intensity analyses of X-ray diffraction patterns, the residual factor was found below 0.13 even for the 15 mol% TDT system. lt was confirmed from the DTA and TGA analyses that any phase transitions did not occur under the experimental condition executed. Comparing the pycnometric density with the lattice parameter obtained from XRD, it was suggested that the predominant defect model be an oxygen vacancy.

• Korean Journal of Breeding Science
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• v.41 no.1
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• pp.1-8
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• 2009

This study was carried out to breed and develop high quality and functional nutrient tomato with multi disease resistance as well as a stable growing adaptation for fresh market usage under protected plastic houses cultivation. The materials were used 5 inbred lines and their 6 hybrids of large tomato group, which have been bred and developed from 1999 to 2007 in Division of Plant Resource Department of Chungnam National University. Fruit weight showed hybrid vigor effect that $F_1$ hybrids weighed more than their parent lines, fruit shape formed three type of oblate, deep oblate and globe shape, in firmness and pericarp thickness have got a high significant correlation, inbred DN611 line was measured the most firm fruit with 6.04 mm pericarp thickness. In fruit color at maturity, pink color crossed to red color appeared all red fruit color in the $F_1$ hybrids, it means red skin color is a dominant gene compared to pink skin color is a recessive gene in tomato, while between fruit skin color and shoulder part color showed no any co-relationship. The sugar content and titratable acid of $F_1$ hybrids inherited an intermediate data of their parent lines, the flavor of KP543 inbred line and the hybrid (JB535 x KP543) revealed the better taste with high brix and proper titratable acid content$^{*}$. In beta carotene content DN611 line showed 2~3 times higher than other materials so that its 3 hybrids contained an increased level of beta carotene, lycopene content was not so much difference among inbred lines and $F_1$ hybrids, of them MD508 contained higher of 8.72 mg and hybrid (JB535 x JA517) had 8.05 mg lycopene content per 100 g fruit, overall pink skin color and red skin color measured a higher lycopene content than yellow and orange skin color at ripe stage. In disease resistance test by PCR marker for Fusarium race2 (I2), Nematode (Mi1), ToMV ($Tm2^2$), Cladosporium (Cf9), (JB535 x JA517) hybrid have got multi-resistance with homozygote band in Nematode, ToMV, Cladosporium and heterozygote band in Fusarium race2. Through this breeding program we could select high quality and functional nutrient with multi resistant $F_1$ hybrids and inbred lines in tomato which are two best hybrids (JB535 x MD508), (JB535 x JA517), additionally developed high beta carotene inbred line DN611 and increased the level of lycopene inbred line MD508. These results will be very useful to make a high quality tomato variety continuously.

• Journal of Oriental Neuropsychiatry
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• v.35 no.3
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• pp.247-256
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• 2024

Objectives: To examine effect of Korean medical treatment on child and adolescent patients with depressive disorder and correlations among changes in anxiety and anger psychological scales before and after treatment. Methods: Medical records of 28 adolescent and 9 child patients diagnosed with depressive disorder based on Diagnostic and Statistical Manual of Mental Disorders-V (DSM-V) who received Korean medical treatment (herbal-medication, acupuncture, Korean psychotherapy, and so on) for at least 8 weeks were retrospectively reviewed. Psychological scales including Beck Depression Inventory-II (BDI-II), State-Trait Anxiety Inventory (STAI), Beck Anxiety Inventory (BAI), State-Trait Anger Expression Inventory (STAXI), Children's Depression Inventory (CDI), State Anxiety Inventory for Children (SAIC), Trait Anxiety Inventory for Children (TAIC), and Children's Inventory of Anger (ChIA) were measured every four weeks and analyzed. Results: After eight weeks of treatment, STAI-X-1 (State Anxiety), STAI-X-2 (Trait Anxiety), BDI-2, BAI, STAXI-S (State Anger), AXI-K-I (Anger Expression-In) and AXI-K-O (Anger Expression-Out) showed statistically significant decreases in adolescent patients. In child patients, ChIA was significantly improved after eight weeks. For psychological scale pairs in adolescent patients, BDI-2 and STAI-X-1·STAI-X-2·BAI·STAXI-S·AXI-K-I, STAIX-T and STAXI-S·AXI-K-I showed significant positive correlations whereas AXI-K-O and AXI-K-C showed a negative correlation. In child paitents, there was a significant positive correlation for all psychological scales except for the relationship between SAIC and ChIA. In adolescent patients, low pretreatment BDI-2 predicted BAI, STAXI-S, and AXI-K-I score reduction after 8 weeks. Lower BAI scores significantly decreased STAI-X-2 and BDI-2 scores after 8 weeks but increased AXI-K-C. In child paitents, low pretreatment ChIA scores predicted a decrease in CDI score after treatment. Conclusions: Korean medical treatments including herbal medicine, acupuncture, and Korean psychotherapy were effective in improving depressive disorder and accompanying symptoms such as anxiety and anger of child and adolescent patients.

• Journal of the Korean Electrochemical Society
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• v.14 no.2
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• pp.98-103
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• 2011

[ $Li[Ni_{0.8}Co_{0.15}Al_{0.05}]O_2$ ]cathode material for lithium secondary battery is obtained using co-precipitation method. To determine the optimal metal solution concentration value, the CSTR coprecipitation was carried out at various concentration values(1-2 mol/L). The surface morphology of coated samples was characterization by SEM(scanning electron microscope) and XRD (X-Ray Diffraction)analyses. Impedance analysis and cyclic voltammogram presented that internal resistance of the cell was dependent upon the concentration of metal solution. such data is very helpful in determining the optimal content of metal solution concentration to enhancing electrochemical property by adjusting powder size distribution and crystal structure.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.141-142
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• 2006

Thermoelectric properties and microstructures of $Sr_{8-x}Ba_xGA_{16}Ge_{30}$ alloys fabricated by the arc-melting method were investigated. The alloys with the nominal composition of $Sr_8Ga_{16}Ge_{30}$ and $Ba_8Ga_{16}Ge_{30}$ were the single-phase alloys, while those of $Sr_4Ba_4Ga_{16}Ge_{30}$ and $Sr_2Ba_6Ga_{16}Ge_{30}$ were two-phases alloys. Electrical resistivity and the Seebeck coefficient for both two-phases alloys were higher in magnitude than those of the single-phase alloys between room temperature and 873K The thermal conductivities for both two-phase alloys were reduced with respect to those of the single-phase alloys in the whole temperature range. The maximum values of ZT for $Sr_4Ba_4Ga_{16}Ge_{30}$ and $Sr_2Ba_6Ga_{16}Ge_{30}$ were achieved with the values of 0.69 at 753K and 0.51 at 754K, respectively, while those of $Sr_8Ga_{16}Ge_{30}$ and $Ba_8Ga_{16}Ge_{30}$ were 0.86 at 758K and 0.76 at 943K, respectively.