• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.674-682
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• 2018

Large industrial motors require a large area because of the high risk of shutdown accidents and large industrial accidents due to the lowering of the dielectric strength of the armature windings and overheating problems. Therefore, there is a demand for a large-capacity motor that has small size, light weight, and excellent dielectric strength compared with conventional motors. Superconducting motors have advantages of high efficiency and output power, low size, low weight, and improved stability. This results from greatly increasing the magnetic field generation by using superconductive field coils in rotating machines such as generators and motors. It is very important to design and analyze the cooling system to lower the critical temperature of the wires to achieve superconducting performance. In this study, a field loss analysis and low-temperature heat transfer analysis of the cooling system were performed through the conceptual design of a 100-HP high-temperature superconducting synchronous motor. The field loss analysis shows that a uniform pore magnetic flux density appears when high-temperature superconducting wire is used. The low-temperature heat transfer analysis for gaseous neon and liquid neon showed that a flow rate of 1 kg/min of liquid neon is suitable for maintaining low-temperature stability of the high-temperature superconducting wire.

• Journal of Acupuncture Research
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• v.34 no.2
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• pp.1-18
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• 2017

Objectives : The purpose of this study was to evaluate the effects of water extracts of Eucommiae cortex (EC), Psoraleae semen (PS), and their combination on receptor activator of nuclear factor-kappa-B ligand (RANKL)-induced osteoclast differentiation. Methods : We assayed the protein expression levels of nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), c-Fos, mitogen-activated protein kinases (MAPKs), and ${\beta}-actin$ in cell lysates using western blotting. Similarly, mRNA expression levels of NFATc1, c-Fos, tartrateresistant acid phosphate (TRAP), and glyceraldehyde-3-phosphate dehydrogenase, spermatogeni (GAPDHS) from bone marrow macrophages (BMMs) were analyzed using reverse transcription-polymerase chain reaction (RT-PCR). Furthermore, we determined the anti-osteoporotic effects of the water extracts of EC, PS, and their combination in a lipopolysaccharide (LPS)-induced bone-loss mouse model. Results : The in vitro data revealed showed that the combination of EC and PS extract showed a more remarkable inhibition of osteoclast differentiation than each herb did alone. The combination downregulated the induction of c-Fos, NFATc1, and TRAP by suppressing the phosphorylation of p38 and c-Jun N-terminal kinases (JNKs) and inhibiting nuclear factor kappa-light-chain-enhancer of activated B cells ($NF-{\kappa}B$). Lastly, the in vivo data showed that PS reduced the LPS-induced bone erosion. Conclusion : The result of this study suggests that EC and PS could be potential therapeutic agents for bone loss diseases such as osteoporosis.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.3
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• pp.336-343
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• 2019

In order to investigate the density of seasonal incidence of mosquitoes, a vector of infectious diseases in Jeju region, this study collected mosquitoes using a Black light trap (BL) and Biogents' Sentinel 2 Mosquito Trap (BG), dividing the region into cattle sheds, habitats for migratory birds, and the downtown area, twice a month for 9 months from March through November 2018. Then, this study conducted identification and classification and checked for the presence of Flavivirus using reverse transcription polymerase chain reaction (RT-PCR). As for the mosquito population, 1,847 mosquitoes (six genera, 12 species) were collected. The places where most mosquitoes were collected were copses near craft workshops in habitats for migratory birds and Jungang-dong in the Seogwipo downtown area. For the population, Culex pipiens pallens was the dominant species (76.9%), followed by Aedes albopictus (8.9%). Most of the population was collected in June, followed by August and October. This study conducted a RT-PCR test with 1,847 collected mosquitoes, which were divided into 50 pools if they had Flavivirus. All turned out to be negative. However, the results of the investigation show the presence of Culex tritaineniorhychus, Aedes albopictus, and Anopheles sinensis and can be used as a basis for the comprehensive prevention management of mosquitoes.

• Korean journal of applied entomology
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• v.58 no.3
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• pp.209-218
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• 2019

This study was conducted to develop a technology for environmentally friendly control of sweet-potato whitefly, Bemisia tabaci, by controlling their behavior using a push-pull strategy in a tomato greenhouse. B. tabaci was attracted the most by yellow color, light source of 520 nm, whereas it avoided the complex light treatment of 450 + 660 nm. The two natural enemies of B. tabaci, Cyrtopeltis tenuis and Orius laevigatus, were attracted the most by 520 nm light source. B. tabaci was repelled by the volatile organic compounds ocimene and carvacrol and was the most attracted by methyl isonicotinate. When buckwheat was added into the tomato greenhouse, the density of C. tenuis was maintained at about 16 times higher than when untreated for 15 days. As a result of the combined treatment of push-pull strategy, the density per trap of B. tabaci was three times lower than when no treatment was applied, and the control of this pest increased with time and reached up to 68.7%.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.6
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• pp.553-557
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• 1999

In order to investigate the optical properties of the $Al_XGa_{1-X}N/GaN$ thin film grown by metalorganic chemical vapor deposition (MOCVD) method, the photoluminescene (PL), photocurrent (PC) and persistent photoconductivity (PPC) measurements were carried out at room temperature. The band gap of the $A1_x$$Ga_{1-x}$N/GaN was determined to 3.70 eV by the PL and PC measurements. The PC measurement on the light illumination from the top of the $A1_x$$Ga_{1-x}$N/GaN thin film provides peaks at 3.70, 3.43, and around 2.2 eV. The PC spectrum by the illumination passing through from the substrate of the sample can be shown at 3.43 eV together with a broad tail band from the GaN band edge to around 2.23 eV. The photocurrent quenching and anomalous PPC decay observed in PPC measurements indicate that metastable electron states are fomed in the band gap of GaN layer to trap electrons which can be tunneled the potential barrier for long recovery time.

• Animal Systematics, Evolution and Diversity
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• v.34 no.3
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• pp.127-142
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• 2018

A new species of Eudactylopus Scott A., 1909 is described from the southern coast of Korea. The specimens were collected using a light trap set overnight at the entrance near a pier. Eudactylopus yokjidoensis n. sp. is similar to E. andrewi Sewell, 1940 and E. spectabilis (Brian, 1923) in two key respects: similar length of proximal and distal inner setae on female P2 enp-2, and modification of two subapical setae on male P2 endopod. However, E. yokjidoensis can be differentiated from the two species by following morphological characteristics: in females, the length ratio of cephalothorax/2nd-4th thoracic somites combined is smaller in E. yokjidoensis than other two species (1 : 0.8 vs. 1 : 1); antennule has nine segments (vs. 7-segmented in E. andrewi); P2 to P4 each bears a process in medial distal margin of basis, while it is just smooth in E. spectabilis; in males; the length ratio of cephalothorax to 2nd-4th thoracic somites combined is smaller in E. yokjidoensis than other two species (1 : 0.6 vs. 1 : 1 in E. andrewi and 1 : 0.8 in E. spectabilis); and P5 exopod has a comb-like innermost seta, while it is bipinnate seta in E. spectabilis. To prove the Korean species of Eudactylopus to be new, full descriptions of both sexes are given here, and the claim is supported by distinct genetic differences between E. yokjidoensis and E. spectabilis (22.3-22.7%) in the mitochondrial gene cytochrome oxidase subunit I(mtCOI) sequence.

• Korean Journal of Medicinal Crop Science
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• v.16 no.1
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• pp.33-38
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• 2008

This study was carried out to reduce the number of chemical treatment by optimal apply for the disease and pest and obtain the basal data of environmental-friendly cultivation in Panax ginseng in 2006. The result by checking disease Incidence and pests fried in ginseng field of jeollabuk-Do was as follows. The kind of disease occurred in Jinan was 8 including Rhizoctonia solani, 7 with Botrytis cinerea in Jeongeup, and also 6 with Botrytis cinerea in Kochang within Jeollabuk-Do. It was required thorough disease control before the rainy season because the occurrence time was peaked around July. Also, the most serious disease in Jeollabuk-Do was Alternaria alternata, Botrytis cinerera, and Colletotrichum gloeosporioides. The actual harmful pests in ginseng field were Asusta despecta steboldiana and Holotrichia sp. and in other method using black light trap, Maladera orientalis, Ostrinia furnacalis, and Holotrichia morosa were mainly trapped.

• Journal of Periodontal and Implant Science
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• v.29 no.2
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• pp.355-373
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• 1999

Many researches have been reported that collagen as cellular stroma, matrix of grafting materials, mediator of agents for the purpose of promoting healing process invivo, but the responses in vivo were seen various. The goal of this experiment is to assess the effect of collagen on bony healing, through histological evaluation of implanted collagen on the calvarial defect in rats. 2-month-old Sprague-Dawley, 24 rats were used and 12 rats assigned to each group of control and test. Defect of 5mm in diameter was made on the calvarial bone with trephine bur. Following thorough saline rinse, defect of control group was left in empty and that of experimental group was filled with fibrillar collagen($COLLATAPE^{(R)}$, COLLA-TEC. INC. U.S.A.) soaked in saline. 3 rats in each group were sacrificed at 3, 7, 14, 21 days after operation respectively, and the tissue blocks were prepared for light microscope with H-E for evaluation of overall healing, with TRAP(tartrate resistant acid phosphatase) for evaluation of osteoclastic activity and with immunohistochemical staining for macrophages. The results were as follows : 1. In the control group, inflammatory responses were disappeared at day 14, but, in the experimental group inflammatory infiltrates were reduced at day 21. Thus, the experimental group showed more severe soft tissue inflammation than control group. 2. Both control and experimental group showed slight appositional growth at day 7 and gradual bony growth to 21th day. But, complete bony healing of the defect was not shown. There was no significant difference in bony healing between control and experimental group 3. Specific response of macrophages for implanted collagen was observed at day 14 in the experimental group. In conclusion, although fibrillar collagen caused inflammation of soft tissue during initial healing period, inflammatory responses by fibrillar collagen didn't inhibit bony regeneration and implanted collagen was biodegradaded by macrophages. Thus, we expect that fibrillar collagen can be used for useful mediator of graft materials or growth factors.

• Journal of Periodontal and Implant Science
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• v.33 no.4
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• pp.573-584
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• 2003

Bone remodeling results from the combined process of bone resorption and new bone formation which is regulated in part by some of Dexamethasone related proliferation & mineralization of cultured bone cell and polypeptide growth factors such as platelet derived growth factor(PDGF), which has been known to be an important local regulator of bone cell activity and participate in normal bone remodeling. To evaluate the effects of Dex and PDGF on bony healing of calvarial defect in rats, 10 ng/ml PDGF were applied on P group and 10 ng/ml PDGF and $10^7$ M Dex were applied PD group. 4 rats in each group were sacrificed at 7, 14. 21 days after operation respectively, and the tissue blocks were prepared for light microscope with H-E for evaluation of overall healing, with TRAP(tartrate resistant acid phosphatase) for evaluation of osteoclastic activity and with immunohistochemical staining for macrophages. The results were as follows : 1. In all group, healing aspects were progressed from 7 days to 21 days in soft and bony tissue, but complete repair were not observed in bony defect 2. PDGF and control group were showed similar bony healing aspect , but bony healing in combination of PDGF-BB and Dex were observed slower aspect compared to PDGF and control group from early healing times. 3. There were no significant difference on activities of osteoclast and macrophages in bony healing between control and experimental group In conclusion, PDGF were not influenced on bony healing of defect and combination of PDGF-BB and Dex were showed slower healing through early healing times. it was considered that Dex compared to PDGF did influenced on early hone formation factors in healing period

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.4
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• pp.265-272
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• 2008

Biodegradable polybutylene succinate(PBS) is an environment friendly plastics for fisheries, because it can mitigate the ghost fishing problem caused by gill-net and trap fisheries. To evaluate photodegradability of PBS monofilament in comparison with polyamide(PA) and polyethylene(PE) monofilament, these 3 types of monofilaments were spun and exposed to ultraviolet light(UV) of weather-ometer for 900 hours, and then their modification, crystal structure, strength, and extensibility were analysed. PBS monofilament did not show any crack and maintained its crystal structure after 900 hour exposure to UV whereas PE monofilament began showing cracks and structure modification after 600 hour exposure. Under UV exposure, the strength and extensibility decreased more rapidly in PBS than in PA and PE. We estimate that gill nets made of PBS monofilament can endure for about 1 year. The breaking strength and elongation decreased linearly with the exposure time for the 3 types of monofilaments. The derived regression equations of the residual tenacity(RT, kg/$mm^2$) and the residual extensibility(RE, %) with the exposure time in year(Y) for each monofilament were; PBS : RT=48.598 - 8.6437Y($R^2=0.93$), RE=28.165 - 7.3233Y($R^2=0.98$), P A : RT=59.771 - 8.6437Y($R^2=0.98$), RE=32.198 - 5.2772Y($R^2=0.92$), P E : RT=60.898 - 5.6528Y($R^2=0.98$), RE=11.887 - 0.7188Y($R^2=0.98$).