• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.12
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• pp.1061-1066
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• 2016

Corrugation of a corrugated panel dramatically increases the bending stiffness per weight. However, corrugated panels show lower sound insulation performance than that of the flat plate having the same weight. Especially, in a particular frequency region, the sound transmission loss significantly decreases. Main reason of the problem is known as the local resonance. A number of local resonance modes occur above a certain frequency band and modal density rapidly increases. In this study, we investigate the relation of the sound transmission loss and the modal density. Finally, we propose a design methodology in terms of the modal density to improve the sound insulation performance of the corrugated panels without weight increase.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.8
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• pp.920-926
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• 2012

Wrinkling is a common phenomenon in nature and the shape of a wrinkle can be defined using characteristic dimensions such as pitch, length, amplitude, and density etc. Wrinkle structure can be utilized in various research fields, and especially it has special characteristics when it used in applications of heat transfer; a wrinkly surface has the effect to promote turbulent flow and increasing surface area. However, the generation of wrinkle structures in somewhat regular is not easy. Till now, there are some research works focused on realization of wrinkles in micro scale. However, most of the processes generally requires high precision equipments and high costs, and also there is a limitation to generate the wrinkles in a large area. In this study, we propose a novel method named as a RCO (repetitive contact-and-open) process to fabricate wrinkle structure with low cost and relative easy way. Using the RCO, we fabricated micro-corrugate structures successfully. From the experimental results, we found out the process parameters of RCO, and showed the possibility of RCO to be used in real applications.

• Animal Systematics, Evolution and Diversity
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• v.2 no.2
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• pp.13-26
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• 1986

A Taxonomic investigation was carried out on the following seven spider mites (Family tetranychidae) by comparison of morphological characters, cuticular lobes and karyotypes. Materials used in this study were collected and reared at Jeonju, Jorea during October 1985-June 1986. Subfamily Bryobiinae ; Bryobia praetiosa Koch, 1836 ; Petrobia latens (Mller, 1776). Subfamily Tetranychinae ; Panonychus citri (McGregor , 1919) ; P.ulmi (Koch, 1836): T vienensis tranychus Zacher , 1920 ; T.urticae (Koch, 1836) ; T. kanzawai Kishida , 1927. Of them two species, P. latens and T. kanzawai , are newly recorded from Korea.

• The Korean Journal of Mycology
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• v.20 no.1
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• pp.1-10
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• 1992

Fresh fungi were collected during field trips to Ullung Island from August, 1990, to September, 1991. Among them, some polyporoid fungi were recognized to the species. Thirty three species were identified, among which nine fungi were confirmed new in Korea and registered here with descriptions. These fungi are Auriporia aurulenta, Ceriporiopsis gilvescens, Ceriporiopsis subvermispora, Gloeophyllum trabeum, Junghuhnia separabilima, Oligoporus stipticus, Oxyporus similis, Phellinus lavigatus, and Polyporus melanopus.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.345-349
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• 2015

The pest species occurring on the aboveground parts of Phalaenopsis orchids were studied for a period of two years (Aug. 2013 to June 2015) at 9 Phalaenopsis farms in Korea. In total, 10 species of insect pest were identified : Tenuipalpus pacificus Baker, Tyrophagus putrescentiae Schrank, Frankliniella occidentalis Pergande, Frankliniella intonsa Trybom, Thrips tabaci Lindeman, Scirtothrips dorsalis Hood, Pseudococcus dendrobiorum Williams, Pseudococcus longispinus Targioni Tozzetti, Coccus hesperidum L., Limax marginatus $M{\ddot{u}}ller$. T. pacificus occurred in most of the farms surveyed in this study (6). The observation frequency of T. pacificus and F. intonsa were highest, they were observed in 10 out of 96 surveys. Although P. longispinus was only observed to occur on two farms, their observation frequency (9 observations, 9.4%) and density (2-289 per 20 plants) were high. Thus, it seems that T. pacificus, F. intonsa, and P. longispinus are the major pests affecting Phalaenopsis orchid farms in Korea.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.18 no.1
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• pp.81-98
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• 1992

Hairless mice (Skh:HR-1) exposed to single doses (0.5, 1.0 and 3. OMED) of UV-B radiation were displayed remarkable changes of barrier function and surface morphology. Trans- epidermal water loss (TEWL) as an index of barrier function was measured by evaporimeter, and wrinkle density (WD) as an index of morphological alteration was measured by image analyzer. Significant changes of TEWL were not observed in the control and 0. SMED group, but 1.OMED and 3. OMED groups noted significant difference. TEWL of 3. OMED group was rapidly increased to the 3rd day and decreased until the 14th day when it reached nearly to normal level, Time-courses of TBWL for 1. OMEB and 3. OMED groups displayed similar pattern, but different only in the magnitude. WD were significantly decreased during the 3rd-5th day in all of the irradiated groups and then increased during the last period to the 14th day, but did not recover the normal level at the 14th day. Time-courses of WD for all groups exhibited similarity, and were entirely dependent on the exposed doses. We also observed histological changes which included hyperplasia, sunburn cell (SBC) formation, accumulation of polymorphonuclear leukocyte (PMNs), and loss of collagen of UVB- exposed hairless mouse skin. Changes of TEWL and WD are helpful in understanding of epidermal and dermal damages by single exposure of UVB.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.4
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• pp.257-263
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• 2016

Recently, an interest has developed in the use of whole green grains as functional food materials. The present study was conducted to provide the baseline data for the stable production of whole green grains in 20 cultivars of wheat by investigating the greenness of grain with maturation (from $20^{th}$ to $41^{st}$ day after heading, at an interval of 3 days). On the $20^{th}$ day after heading, the grains were dark green with a wrinkled long-oval shape. After the $35^{th}$ day of heading, the grains turned almost yellow with an oval shape. Their redness ('a' value of chromaticity) increased from the $20^{th}$ to $41^{st}$ days after heading, indicating a negative value up to the $32^{nd}$ day after heading. A significant decrease in their chlorophyll content was observed with maturation. The yield of whole green wheat grain (including greenish yellow grain) was the highest from the $32^{nd}$ to $35^{th}$ after heading. Therefore, we concluded that the optimal harvesting period for whole green wheat grain was from the $32^{nd}$ to $35^{th}$ day after heading. The heading time of various cultivars ranged from April 28 to May 5, the time of Jopummil cultivar grew the fastest among them, such as Gurumil, Alchanmil, but Dahongmil got the latest in heading time. The greenness of seven cultivars (Jeokjungmil, Keumkangmil, Jogyeongmil, Jopummil, Baekjungmil, Yeonbaekmil, and Milseongmil) was relatively higher than that of the others. The yield of greenish whole grain was relatively high in six cultivars (Alchanmil, Baekjungmil, Eunpamil, Yeonbaekmil, Dahongmil, and Urimil). Based on their greenness and yield, the Baekjungmil and Yeonbaekmil cultivars have been considered to be optimal for the production of whole green wheat grain.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.1
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• pp.65-72
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• 2009

Skin aging appears to be principally attributed to a decrease in both levels of Type I collagen and regeneration ability of dermal fibroblasts. It is important to introduce an efficient and safe agent for effective management of skin aging. To this end, we performed screening for anti-ageing agents and then found that vegetable peptones (pea and wheat) promoted cell proliferation of adult stem cells. Vegetable peptones may be considered as useful medium additives because it can supply nutrients, peptides, amino acids or growth factor analogues. This study was designed to investigate effects of vegetable peptones on cell proliferation/collagen production and their possible mechanisms in human dermal fibroblasts. In cell proliferation assay, vegetable peptones significantly promoted cell proliferation in a concentration-dependent manner. In addition, human COL1A2 promoter luciferase and type I procollagen synthesis assays showed that vegetable peptones induce type I procollagen production through the activation of COLlA2 promoter. In both TGF-${\beta}1$ luciferase reporter and ELISA assays, vegetable peptones was found to induce TGF-${\beta}1$ production, suggesting that vegetable peptones induce type I procollagen production through the activation of TGF-${\beta}1$. When applied topically in a human skin twice a day for an 4-week period of time, vegetable peptones did not induce any adverse reactions. Theretore, based on these results, we suggest the possibility that vegetable peptones may be considered as an attractive, wrinkle-reducing candidate for topical application.

• Journal of the Korean Society for Nondestructive Testing
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• v.26 no.2
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• pp.108-114
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• 2006

Transient and asymmetric density distributions of butane flow have been investigated from laser image signals by developed three-dimensional digital speckle tomography. Moved signals of speckles have been captured by multiple CCD images in three angles of view simultaneously because the flows were asymmetric and transient. The signals of speckle movements between no flow and downward butane flow from a circular half opening have been calculated by a cross-correlation tracking method so that those distances can be transferred to deflection angles of laser rays fur density gradients. The three-dimensional density fields have been reconstructed from the fringe shift signal which is integrated from the deflection angle by a real-time multiplicative algebraic reconstruction technique (MART).

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.662-668
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• 2004

Ames test revealed most methanol extracts of 13 Korean wild mushroom species have strong antimutagenic effects against N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and benzo(a)pyrene[B(a)P]. Methanol extracts of Coriolus versicolor and Phaeolepiota aurea showed 74-94 and 83-88% antimutagenic effects against MNNG and B(a)P in Salmonella typhimurium TA100 strain, while 89 and 91% inhibitions were observed against B(a)P in TA98 strain, respectively. Most water extracts of wild mushrooms did not show antimutagenic activeiy on MNNG and B(a)P. Wild mushrooms extracts inhibited human colon carcinoma cells (HT29), human hepatoma cell (HepG2), and humann histiocytic lymphoma cell (U937) dose-dependently, with most methanol extracts exhibiting stronger effect than water extracts, Highest toxicity was observed against HT-29 cells in methanol extracts of Coriolus versicolor and Phaeolepiota aurea, showing 84% inhibition at 1 mg/mL, whereas C. versicolor water extract showed 53-65% inhibition against HepG2 and U937. These extracts did not show cytotoxic effects against human lymphocyte. Results revealed wild mushrooms have strong antimutagenic and in vitro cytotoxic effects.