• Journal of Soil and Groundwater Environment
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• v.15 no.3
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• pp.1-6
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• 2010

This study investigated the change of metal contamination levels according to amendment of enforcement regulation of the Soil Environmental Conservation Act in Korea. As an analytical result of 87 samples in abandoned metallic mine area, the extracted amount of As, Pb and Cu with aqua regia was 4.3~29.6 times higher than that with hydrochloric acid extraction and the number of samples, which contamination levels were found to exceed soil contamination standards, was also increased. On the other hand, in case of Cd, Zn, and Ni, the number of samples, which contamination levels were found to exceed soil contamination standards, was decreased or similar. These results can be used as a preliminary material in comparison between the soil pollution data accumulated previously and the data obtained by the revised standard method for the examination of soil pollution.

• Korean Journal of Materials Research
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• v.16 no.2
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• pp.123-128
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• 2006

[ $BaMgAl_{10}O_{19}:Mn^{2+}$ ](BAM:Mn) phosphor particles with spherical shape were prepared by spray pyrolysis from colloidal solution with silica. The phosphor particles prepared by spray pyrolysis from aqueous solution had irregular morphology after high temperature post-treatment. On the other hand, the phosphor particles prepared from spray solution with colloidal silica had spherical shape after post-treatment. Colloidal silica used as additive improved the spherical shape and filled morphology of the precursor particles prepared by spray pyrolysis. The precursor particles with filled structure produced the BAM:Mn phosphor particles with spherical shape and non-aggregation characteristics after post-treatment at $1400^{\circ}C$ under reducing atmosphere. The phosphor particles prepared from colloidal solutions formed the crystal structure of BAM:Mn phosphor irrespective of the silica contents. The BAM:Mn phosphor particles prepared from aqueous and colloidal solutions had similar photoluminescence intensities under vacuum ultraviolet.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.1
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• pp.107-125
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• 2020

Indigo [鴉靑] was used as a symbolic color in 15^th century diplomacy. This study reinforces the historical research for characteristic and shapes of indigo colored royal clothing gift in King Seongjong's reign with a focus on po [袍] and ieom [耳掩]. Clothing made of fur that was combined with satin damask, silk gossamer [綃] were frequent gift, and a sable coat was a symbol of high-ranking clothes. Another clothing's materials were satin damask, sheer fabric gauze [羅], cotton, tabby with silk and ramie [紵絲]. The indigo color of King Seongjong's reign was recommended not for luxury. Historical research factors for indigo clothing gift were extracted from noblemen's relics. Danryeong and jigryeong are shaped of narrow sleeves and trapezoid gusset pleated in and out. Sable coat can consist of satin damask outshell, sable lining, and double oblique collar. Heohyung are presumed types of short sleeved fur vests. Ieom can be reconstructed with an indigo fabric outshell and sufficient fur. Dapho has gusset pleated wide and narrow. As additional gifts, the shapes of yoseon-cheopri and cheopri were analyzed. We selected a commercial fabric similar to relics and an indigo powder dyeing method to remedy a lack of traditional material. The reconstructed data were presented as flat drawings and samples.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.2
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• pp.312-319
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• 2004

The purpose of this study is to provide information for the manufacturer of shoes. The data was collected through a questionnaire on purchasing practices, wearing state and overall satisfaction with shoes for high school students. The questionnaire survey was conducted on 598 high school students(49.2％ male students, 50.8％ female students) in the Cheongju area. Statistical tests such as frequencies, percentages, and crosstabs were conducted to analyze the data. The results were as follows： 1) The main reasons for buying new shoes were replacing worn out shoes or color and design coordination with other apparel. 2) Male students bought shoes generally from shoe stores and sports brand retailers, but female students bought mainly from shoe stores. The order of criteria considered for purchasing was design, size, price, color, style coordination and comfort. 3) While attending school, male students geneially wore sports shoes, but female students wore sports shoes and dress shoes by similar ratio. 4) The male students used primarily ordinary sports shoes and casual shoes secondarily, and for female students, primarily ordinary sports shoes and sneakers secondarily. 5) They were satisfied with shoe design and color but quality of the material and durability were unsatisfactory. 6) When they wore shoes for long hours, they experienced fatigue of the whole leg and general discomfort, blisters on the feet, and red skin.

• Economic and Environmental Geology
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• v.26 no.4
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• pp.499-505
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• 1993

The Imgye hornblendites occur as intrusive sills or dykes within the mylonite zone developed along the contact boundary between Precambrian Jungbongsan granite and Cambrian Jangsan quartzite or Myobong slate formations. The hornlendites belong to the subalkaline and tholeiitic series. In tectonomagmatic discrimination diagrams such as $TiO_2-K_2O-P_2O_5$, 2Nb-Zr/4-Y and $TiO_2-10MnO-10P_2O_5$, the hornblendites are classified into continental- and island-arc tholeiites. The hornblendites show fractionated REE patterns with $(La/Yb)_{CN}$ ranging from 3.73-4.56. In incompatible element abundance variations, the hornblendites show distinctive positive and negative anomalies for Rb and Nb, respectively, and unfractionated patterns of immobile incompatible elements such as Y and Yb. The REE patterns of the hornblendites are also similar to those of typical continental back-arc tholeiites and those of the Precambrian Okbang amphibolites in the Socheon-meon, Bonghwa-gun. Accoiding to geochemical characteristics above-mentioned, the hornblendites seem to have been formed from tholeiitic magmas of depleted upper mantle source, contaminated by crustal material en route to continental back-arc basin.

• International Journal of Aeronautical and Space Sciences
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• v.14 no.4
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• pp.324-333
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• 2013

The purpose of this paper is to improve the efficiency of multi-objective topology optimization using a genetic algorithm (GA) with bar-system representation. We proposed a new GA using an elite initial population obtained from a Solid Isotropic Material with Penalization (SIMP) using a weighted sum method. SIMP with a weighted sum method is one of the most established methods using sensitivity analysis. Although the implementation of the SIMP method is straightforward and computationally effective, it may be difficult to find a complete Pareto-optimal set in a multi-objective optimization problem. In this study, to build a more convergent and diverse global Pareto-optimal set and reduce the GA computational cost, some individuals, with similar topology to the local optimum solution obtained from the SIMP using the weighted sum method, were introduced for the initial population of the GA. The proposed method was applied to a structural topology optimization example and the results of the proposed method were compared with those of the traditional method using standard random initialization for the initial population of the GA.

• Food Science of Animal Resources
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• v.18 no.4
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• pp.364-370
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• 1998

This study was carried out to establish optimum smoking conditions i.e., smoking temperature, time, and smoking material for meat products. Smoking materials employed for smoking were oak and apple trees. Roast ham and wiener produced by various smoking conditions wree subjected to polycyclic aromatic hydrocarbons (PAHs) analysis. Benzo(a)pyrene was not detected in roast ham and wiener prepared with oak wood smoked and apple wood smoked at 250$^{\circ}C$. The content of benzo(a)pyrene in roast ham and wiener with apple wood smoked at 400$^{\circ}C$ were 0.6 and 0.7 $\mu\textrm{g}$/kg, and those sample smoked at 500$^{\circ}C$ is not suitable for meat products due to the high production rate of benzo(a)pyrene. The higher smoking temperature of the products, the higher the content of PAHs. The similar tendency was observed in smoking time. PAHs contents of the products smoked with oak wood was ranged from non-dection to 0.5 $\mu\textrm{g}$/kg. Meat products smoked for 75 min. were found to be highly valuable from the viewpoints of flavour and color.

• Food Science of Animal Resources
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• v.32 no.3
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• pp.308-315
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• 2012

This study was conducted to examine the effects of egg shell membrane hydrolysates (ESMH) on skin whitening, wound healing, and UV-protection. ESMH was divided into three groups by molecular weight (Fraction I: above 10 kDa of ESMH, Fraction II: 3 kDa-10 kDa of ESMH, Fraction III: below 3 kDa of ESMH). As a result, all of ESMHs showed over 90% of protein contents. The wound healing experiment using HaCaT cells showed that the fraction I was slightly superior to other fractions depending on the concentration though it was not significantly different. In the experiments of inhibition of tyrosinase and L-3,4-dihydroxyphenylalanine (L-DOPA) oxidation to verify the L-DOPA whitening effect, the whole ESMH (before fractioning) showed a similar amount of inhibition effect with arbutin (control). In the inhibition of melanin formation in B16-F1 melanoma cells, the fraction I showed a high inhibitory effect. In the experiment for protecting the skin from ultraviolet rays using HaCaT cells, all the fractions showed a higher rate of cell viability than the control. In conclusion, this study confirmed that the cosmetic effects of ESMHs such as skin whitening, wound healing, and UV-protection, which were divided depending on the molecule weight. We could confirm that the possibility of ESMHs as a material for functional cosmetics.

• Food Science of Animal Resources
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• v.37 no.1
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• pp.38-43
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• 2017

This study was conducted to investigate the physical and sensory properties of ice cream containing fermented pepper powder. Three ice cream formulas were manufactured: 1, control; 2, supplemented with 0.1% fermented pepper powder; and 3, supplemented with 0.2% fermented pepper powder. Formulas 2 and 3 had significantly higher viscosity and lower overrun than formula 1 (p<0.05). Additionally, ice creams supplemented with fermented pepper powder were harder and maintained their forms longer than the controls. 0.2% fermented pepper powder added ice cream had no pungency as much as that of control and overall sensory attribute was not significantly different from control. Therefore, ice cream containing fermented pepper powder maintained physical and sensory properties similar to the controls, and maintenance was better. It means fermented pepper powder ice cream can be utilized as the material of functional food (dessert).

• Journal of Korea Foundry Society
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• v.38 no.2
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• pp.41-47
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• 2018

In a numerical study, equations relating the mechanical properties and cooling rate in a casting process have been applied to an AC4CH cast aluminum alloy. Good agreement was found between the measured and predicted material properties. Step-shaped steel blocks were made to comprise a casting mold with a Y-shaped cavity. Thermometers were inserted into each step of the mold to investigate temperature changes. The microstructure and mechanical properties, such as hardness and tensile stress were measured for each cut of piece. The correlation between the cooling rate and SDAS was found by curved fitting. Moreover, both the solidification time and the temperature were simulated using a commercial package, ZCast. The simulation results for yield strength, tensile strength, elongation, and hardness were compared with experimental results. Using the estimated K and n values, the hardness values of a ship propeller were simulated, and the results were similar to those obtained for actual castings.