• ALGAE
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• v.32 no.1
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• pp.15-28
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• 2017

Morphological, molecular and chromosomal studies were carried out on Tauya basicrassa, an endemic kelp species distributed on the northern continental coast of the Sea of Okhotsk in Russia. The sporophytes of T. basicrassa grow up to 3-6 m long, 1.8-2.2 m wide, and 6.5-7 kg wet weight. The thallus has a blade with very thick narrow basal portion and thinner and much broader upper portion, which usually splits into 3 bullated lobes. A dwarf laminariacean alga, which did not show any morphological similarity to the other species of the order Laminariales, was found from the same locality. The blade of this alga is thin and soft, reached 26-34 cm long and 6-6.5 cm wide and had 4 longitudinal rows of bullations that covered the entire blade. Molecular analysis showed that the dwarf alga has 100% sequence identity in plastid-encoded RuBisCo spacer, mitochondrial cytochrome c oxidase subunit 1 and nuclear-encoded rDNA genes with normal sporophytes of T. basicrassa, indicating that they are different life forms of the same species. Fluorescent DAPI staining showed that the nucleus in the normal sporophyte was 50-65% larger than those of the dwarf ones. Chromosome count using acetocarmine staining showed n = ca. 20 for the normal sporophytes of T. basicrassa and n = ca. 10 for the dwarf one. These results suggest that the dwarf thallus is a haploid parthenosporophyte of T. basicrassa, which developed in nature. This is the first evidence of parthenosporophytes of the laminariacean algae occurring naturally in the field.

• Korean Journal of Veterinary Research
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• v.59 no.1
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• pp.17-24
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• 2019

Animal models of osteoarthritis (OA) have played a key role in understanding the etiology of OA and in the development of new therapeutic strategies. Although pigs have an advantage as an animal disease model due to their similarity to humans, there are few studies on the induction of OA in minipigs. Therefore, this study aimed to characterize disease progression of OA in total medial meniscectomy (TMM)-operated skeletally mature minipigs, up to day 180 postoperatively. There were no significant alterations in vital signs or hematological indices throughout the observation period. However, clinical manifestations of OA in the medial femoral condyles of TMM-operated minipigs were progressive, depending on postoperative duration, with respect to osteophytes formation and roughened surfaces on radiological observation, cartilage erosion under macroscopic examination, and severe cartilage defects including fibrillation, vertical fissures, and cartilage denuding on histopathological observation, with the highest score indicating late-stage OA on day 180 and without indicating apparent variation between subjects. In particular, the lateral femoral condyles were also degenerated, possibly due to localization of weight-bearing from both menisci to the lateral meniscus. Therefore, TMM in minipigs is suitable for reproducible induction of degenerative changes in the femorotibial joints that closely resemble late-stage OA, and is suitable for use in further research.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.413-416
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• 2014

Recently, demand for various leisure sports gradually increases, as people's sense of values changes into leisure-centered one according to the change of given social circumstance and the change of customer needs all over the world. The actual condition is that an interest and participation rate especially in water leports during the summer increases. And needs for various hull design of standardized boat for water leisure increase. Therefore, this paper is intended to develop a recommendation system to design a boat for water leisure by using the collaborative filtering technique in order to make it possible to actively cope with the change of various customer needs for hull design. To this end, emotion relating to kayak design was selected through consumer survey, and emotion was derived by factor analysis and assessment, and then a kayak design layout in the aspect of customer's emotional preference was presented. Besides, an analysis was made according to the elements such as hull, body, and propulsion system of kayak in order to select emotional words according to the kayak design reflecting user's preference, and then a boat model for water leisure in conformance with user's preference was presented.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.5
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• pp.899-908
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• 2022

In this study, a study was conducted to localize a large aluminum turbo fan used for tank powerpack. The turbo fan was scanned with a 3D scanner and then 3D modeling was performed. Computational fluid dynamics (CFD) were performed from the performance conditions of the fan, and structural analysis was performed using the pressure data obtained from CFD. The fan was reduced to 1/5 size by applying the geometric similarity. A 1/5 size fan has a honeycomb structure inserted into the front shroud and back shroud to reduce the weight by 5.3%. A 1/5 size fan was printed using a PBF 3D printer, and a 1/5 size fan with honeycombs was also printed. The pressure drop of 8.67 kPa and the required power of 138.19 kW, which satisfies the performance conditions of the fan, were confirmed from the results of CFD. The values of the maximum deformation amount of 0.000788 mm and the maximum effective stress of 0.241 MPa were confirmed from the structural analysis results. The fan printed by the PBF 3D printer had the same shape as the modeling, and the shape was perfect. There are no defects anywhere in appearance. However, the condition of the outer surface of the fan's back shroud is rough compared to other locations. The fan in which the honeycomb was inserted was also perfectly output, and the shape of the honeycomb was the same as the modeling.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.7
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• pp.910-916
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• 2021

In modern society, various digital communication equipment is being used due to the influence of the 4th industrial revolution. Accordingly, interest in removing noise generated in a data transmission process is increasing, and research is being conducted to efficiently reconstruct an image. In this paper, we propose a filtering algorithm to remove the AWGN generated in the digital image transmission process. The proposed algorithm classifies pixels with high similarity by selecting regions with similar patterns around the input pixels according to block matching to remove the AWGN that appears strongly in the image. The selected pixel determines the estimated value by applying the weight obtained by the local steering kernel, and obtains the final output by adding or subtracting the input pixel value according to the standard deviation of the center mask. In order to evaluate the proposed algorithm, it was simulated with existing AWGN removal algorithms, and comparative analysis was performed using enlarged images and PSNR.

• Journal of Science Education
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• v.42 no.2
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• pp.256-271
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• 2018

The study aimed to investigate how the science gifted connect and integrate science concepts in the process of problem finding. Research subject was sampled from 228 applicants for a science gifted education center affiliated with a university in 2015. A creative problem solving test (CPST) in science, which administered as an admission process, was utilized as a reference to sample two groups. Sixty-seven students from top 30% in test scores were selected for the upper group and 64 students from bottom 30% in test scores were selected for the lower group. The CPST, which was developed by researchers, included one item about how to connect two science concepts among eight science concepts, sound, electricity, weight, temperature, respiration, photosynthesis, weather, and earthquake extracted from elementary science curriculum. As results, there were differences in choosing two concepts among four science major areas. The ways of connecting science concepts were characterized by three categories, relation-based, similarity-based, and dissimilarity-based. In addition, relation-based was characterized by attributes, means, influences, predictions, and causes; similarity-based was by attributes, objects, scientific principles, and phenomena, and dissimilarity-based was by parallel, resource, and deletion. There were significant (p<.000) differences in ways of connecting science concepts between the upper and the lower groups. The upper group students preferred connecting science concepts of inter-science subjects while the lower group students preferred connecting science concepts of intra-science subject. The upper group students showed a tendency to connect the science concepts based on similarity. In contrast, the lower group students frequently showed ways of connecting the science concepts based on dissimilarity. In particular, they simply parallelled science concepts.

• Journal of Life Science
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• v.28 no.6
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• pp.639-647
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• 2018

A new heat shock protein 70 was identified in red-spotted grouper (Epinephelus akaara) based on an expression analysis. The cDNA of red-spotted grouper Hsp70 (designated RgHsp70) was cloned by the rapid amplification of cDNA ends (RACE) techniques. The full-length of RgHsp70 cDNA was 2,152 bp, consisting of a 5'-terminal untranslated region (UTR) of 105 bp, a 3'-terminal UTR of 274 bp, and an open reading frame (ORF) of 1,773 bp that encode a polypeptide of 590 amino acids with a theoretical molecular weight of 64.9 kDa and an estimated isoelectric point of 5.2. Multiple alignment and phylogenetic analyses revealed that the RgHsp70 gene shares a high similarity with other Hsp70 fish genes. RgHsp70 contained all three classical Hsp70 family signatures. The results indicated the RgHsp70 is a member of the heat shock protein 70 family. RgHsp70 mRNA was predominately expressed in the liver, with reduced expression noted in the head-kidney tissues. The expression analysis of different water temperatures (21, 18, 15 and $12^{\circ}C$) for sampled livers revealed that expression gradually increased at $12^{\circ}C$ compared to $21^{\circ}C$. In this study, the effects of water temperature lowering on the physiological conditions were investigated, and the results revealed that novel RgHsp70 may be an important molecule involved in stress responses.

• Korean Journal of Microbiology
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• v.41 no.3
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• pp.201-207
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• 2005

A phenanthrene-degrading bacterium HS362, which is capable of using phenanthrene as a sole carbon and energy source, was isolated from oil contaminated soil. This strain is a gram negative, rod shaped organism that is most closely related to Sphingomonas paucimobilis based on biochemical tests, and belongs to the genus Sphingomonas based on fatty acids analysis. It exhibited more than $99.2{\%}$ nucleotide sequence similarity of 16S rDNA to that of Sphingomonas CF06. Thus, we named this strain as Sphingomonas sp. HS362. It degraded $98{\%}$ of phenanthrene after 10 days of incubation when phenanthrene was added at 500 ppm and $30{\%}$ even when phenanthrene was added at 3000 ppm. Sphingomonas sp. HS362 could also degrade low molecular weight PAHs(Polycyclic aromatic hydrocarbons) such as indole and naphthalene, but was unable to degrade high molecular weight PAHs such as pyrene and fluoranthene. The optimum temperature and pH for phenanthrene degradation were $30^{\circ}C$ and $4{\~}8$, respectively. Sphingomonas sp. HS362 could degrade phenanthrene effectively in the concentration range of NaCl of up to $1{\%}$. Its phenanhrene degrading ability was enhanced by preculture, suggesting the possibility of induction of phenanthrene degrading enzymes. Starch and surfactants such as SDS, Tween 85, and Triton X-100 were also able to enhance phenanthrene degradation by Sphingomonas sp. HS362. It carries five plasmids and one of them, plasmid p4, is considered to be involved in the degradation of phenanthrene according to the plasmid curing experiment by growing at $42^{\circ}C$.

• Toxicological Research
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• v.31 no.4
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• pp.371-392
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• 2015

TS-DP2 is a recombinant human granulocyte colony stimulating factor (rhG-CSF) manufactured by TS Corporation. We conducted a four-week study of TS-DP2 (test article) in repeated intravenous doses in male and female Sprague-Dawley (SD) rats. Lenograstim was used as a reference article and was administered intravenously at a dose of $1000{\mu}g/kg/day$. Rats received TS-DP2 intravenously at doses of 250, 500, and $1000{\mu}g/kg/day$ once daily for 4 weeks, and evaluated following a 2-week recovery period. Edema in the hind limbs and loss of mean body weight and body weight gain were observed in both the highest dose group of TS-DP2 and the lenograstim group in male rats. Fibro-osseous lesions were observed in the lenograstim group in both sexes, and at all groups of TS-DP2 in males, and at doses of TS-DP2 $500{\mu}g/kg/day$ and higher in females. The lesion was considered a toxicological change. Therefore, bone is the primary toxicological target of TS-DP2. The lowest observed adverse effect level (LOAEL) in males was $250{\mu}g/kg/day$, and no observed adverse effect level (NOAEL) in females was $250{\mu}g/kg/day$ in this study. In the toxicokinetic study, the serum concentrations of G-CSF were maintained until 8 hr after administration. The systemic exposures ($AUC_{0-24h}$ and $C_0$) were not markedly different between male and female rats, between the administration periods, or between TS-DP2 and lenograstim. In conclusion, TS-DP2 shows toxicological similarity to lenograstim over 4-weeks of repeated doses in rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.25-31
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• 2001

Characteristics (salt concentration, weight loss, soluble solid content, moisture content, pH, textural properties) of kakdugi radish cube (kakdugi radish, $2{\times}2{\times}2\;cm$) were evaluated during salting. Five different radish cultivars harvested in autumn were immersed into 10, 15 or 20% brine solution (radish : brine solution = 1 : 2) at $15^{\circ}C$ for 5hrs. The time required to reach the optimum salt concentration (3.0%) was different among cultivars; in the 10% brine solution, 5hr for 'Taeback', 4hr for 'Bakja', 3hr for 'Kwandong' and 'Bakbong', 2hr for 'Bagkwang'. Generally, it was observed that it took shorter salting time at higher concentration of brine solution. While the highest value of weight loss of kakdugi radish cubes was observed with 'Bagkwang', the lowest, 'Taeback'. There was a decrease of pH of kakdugi radish during salting; while 'Bakja' showes little change in pH, 'Bagkwang' shows large decrease of pH. Hardness and fracturability decreased during salting; the highest value of hardness was observed with 'Taeback', the lowest, 'Bagkwang' has the highest moisture content, the lowest soluble solid content and hardness. There was a similarity of characteristics of kakdugi radish cube between two cultivars, 'Taeback' and 'Bakja', as well as 'Bagkwang', and those of 'Kwandong' and 'Bakbong' were between two types of cultivars.