• Journal of Sasang Constitutional Medicine
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• v.12 no.1
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• pp.48-62
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• 2000

Creativity is the most important characteristic and ability in the 21st century. Recently leading people in Korean society are aware of the significance of the enhancement of the creativity. However, Korean students are less likely to take initiative or depart from standard ways of thinking or doing things, because Korean Confucius culture puts an emphasis on collectivism. An individual has an obligation to conform in order to avoid conflict and maintain social harmony. The rule of respecting parents and teachers leads to a lack of self-expression and entails silence. Brainstorming technique developed by American Osbron, who originated the group brainstorming in 1953, is the most popular creative thinking method for the students. Brainstorming technique has two principles : ideation can be more productive if criticism is concurrently excluded; The more ideas the better. In doing BS, each panel should consist of chairperson, an assistant chairperson, recorder, and 10 others including 2-3 females. However there are several problems in doing group BS, such as production blocking, uniformity thinking, evaluation apprehension, and social loafing. This study was undertaken to investigate the proper way of forming Brainstorming groups with Korean students according to the Sasang Constitutional Medicine originated by Korean Lee Je-ma in 1894. Human beings are classified in four group in Sasang Constitutional Medicine : Taeyang-In, Teaum-In, Soyang-In and Soum-In. Two Yang-Ins are more self-expressive : Taeyang-In has very unique ides and thoughts; Soyang-In is very humorous and like to present his/her ideas. On the other hand, two Um-Ins are passive and are not likely to speak out their ideas in group. Therefore, in this investigation firstly, the brainstorming group was formed with two Yang-Ins (Taeyang-In and Soyang-In) and two Um-Ins(Taeum-In and Soum-In) separately and secondly, Yang-Ins and Um-Ins were mixed. And the first method was compared with the second method in terms of the degree of participation of the group members and finally the better grouping method to produce more and better ideas was discussed and suggested for the educational system.

• Korean Journal of Materials Research
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• v.30 no.4
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• pp.176-183
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• 2020

The high-temperature stability of YSZ specimens fabricated by die pressure and cold isostatic press (CIP) is investigated in CaCl₂-CaF₂-CaO molten salt at 1,150 ℃. The experimental results are as follows: green density 46.7 % and 50.9 %; sintering density 93.3 % and 99.3 % for die press and CIP, respectively. YSZ foremd by CIP exhibits higher stability than YSZ formed by die press due to denseness dependency after high-temperature stability test. YSZ shows peaks mainly attributed to CaZrO₃, with a small t-ZrO₂ peak, unlike the high-intensity tetragonal-ZrO₂ (t-ZrO₂) peak observed for the asreceived specimen. The t-ZrO₂ phase of YSZ is likely stabilized by Y₂O₃, and the leaching of Y₂O₃ results in phase transformation from t-ZrO₂ to m-ZrO₂. CaZrO₃ likely forms from the reaction between CaO and m-ZrO₂. As the exposure time increases, more CaZrO₃ is observed in the internal region of YSZ, which could be attributed to the inward diffusion of molten salt and outward diffusion of the stabilizer (Y₂O₃) through the pores. This results in greater susceptibility to phase transformation and CaZrO₃ formation. To use SOM anodes for the electroreduction of various metals, YSZ stability must be improved by adjusting the high-density in the forming process.

• Polymer(Korea)
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• v.34 no.1
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• pp.32-37
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• 2010

Photo-alignment property of groove patterned surface prepared from blend of poly (vinyl cinnamate) (PVCi) and oligomeric dicinnamate was investigated for the application for alignment layer of liquid crystal display. The study of the photoreaction kinetics using UV-vis spectrum with the irradiation time showed that the reaction rate of oligomeric cinnamate was enhanced compared to that of PVCi. Blend where PVCi was main component showed a slight improvement on the photoreaction rate. It was unable to obtain groove patterned surface only using oligomeric cinnamate itself owing to the high crystalline character. However, blending of PVCi made it possible to obtain clear surface pattern. Molecular orientation could be confirmed from the polar plot data. It can be suggested that blend of oligomeric cinnamate and polymeric cinnamate is promising material for the photoalignment layer.

• Nuclear Engineering and Technology
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• v.24 no.1
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• pp.75-85
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• 1992

The texture changes and their effect on the 0.2% yield strength of Zircaloy-4 sheet were examined after quenched from the ($\alpha$+$\beta$) phase temperature. When the prior ($\alpha$+$\beta$) gram size was slightly larger than that of the $\alpha$-annealed, the observed texture was similar to the $\alpha$-annealed texture having an ideal orientation of the (0001) basal pole at 30$^{\circ}$away from the normal direction toward the transverse direction. When the prior ($\alpha$+$\beta$) grain size was twice as large as that of the $\alpha$-annealed, the location of maximum basal pole intensity was distributed between the transverse and the rolling direction making an angle 15$^{\circ}$from the normal direction, and the observed texture became isotropic. It was found that the Kearns texture parameter, fr, in the rolling direction increased steadily, and fr in the transverse direction increased slightly, while fr in the the normal direction decreased with increasing heat treatment time. With a small increase in fr, the 0.2% yield strength increased drastically. The influence of texture was analyzed by deriving the Schmid orientation factors and the resolved shear stresses for the deformation systems. It was found that the large increase in the 0.2% yield strength was attributed mainly to the microstructural changes and partly to the texture changes by the ($\alpha$+$\beta$) heat treatment.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.13-19
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• 2011

Semen cryopreservation induces the formation of reactive oxygen species (ROS), and the ROS cause sperm damage. We aimed to investigate the effects of the antioxidative enzyme catalase (CAT) on sperm quality and ROS during cryopreservation. Sperm rich fractions collected from five Duroc boars were cryopreserved in freezing extender with (200 or 400 U/mL) or without CAT (control). After thawing, sperm motility, viability, normal morphology, plasma membrane integrity, mitochondrial function and intracellular ROS were evaluated. CAT significantly improved total sperm motility at a concentration of 400 U/mL (P < 0.05), but didn't improve progressive sperm motility, viability, morphological defects, plasma membrane integrity and mitochondrial function in frozen-thawed boar sperm. In evaluation of ROS, CAT had no effect on reduction in ${\cdot}O_2$, but scavenged $H_2O_2$ in viable frozen-thawed boar sperm at concentrations of 200 and 400 U/mL (P < 0.05). In conclusion, CAT was not enough to improve quality of frozen-thawed sperm, but can reduce $H_2O_2$ generation in viable boar sperm during cryopreservation.

• Journal of Veterinary Clinics
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• v.26 no.1
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• pp.36-40
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• 2009

The purpose of this study was to determine the incidence and therapeutic outcomes of canine oral tumors in Korea. Medical records of dogs presented with oral tumor at the Veterinary Medical Teaching Hospital of Seoul National University from 2002 to 2007 were reviewed. The predominant breeds were Yorkshire terrier (n=14), miniature poodle (n=7), Shih Tzu (n=6), and maltese (n=4), in order. The mean age at onset was $10.0{\pm}3.8$ years. The most common tumor types included fibrous epulis (n=13), malignant melanoma (n=12), acanthomatous epulis (n=4), and squamous cell carcinoma (n=3). Surgical removal was performed in 29 cases; simple excision in 18 cases, partial mandibulectomy in 8 cases, and partial maxillectomy in 3 dogs. Outcomes of surgery were various according to the tumor types. Prognosis of dogs with fibrous epulis and acanthomatous epulis was good and that of dogs with malignant melanoma was poor.

• Journal of Veterinary Clinics
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• v.34 no.6
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• pp.414-419
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• 2017

The present study aimed to document the biomechanical findings of soft tissue reconstruction surgeries for the treatment of medial patellar luxation in dogs. Stifle joints (n = 12) from dogs weighing 4.1-8.4 kg were used in this study. The following soft tissue reconstruction techniques used for the treatment of medial patellar luxation were selected for this study: vastus medialis release, medial retinacular release, and capsule release for medial realignment (n = 6), and retinacular imbrication and anti-rotational suture for lateral realignment (n = 6). A 5-kg traction using an electronic scale was applied at $45^{\circ}C$ laterally for medial realignment and medially for lateral realignment. Fluoroscopic imaging was used to measure the length of patellar displacement (LPD) in each technique. Among medial realignment techniques, capsule release had the highest horizontal LPD; vastus medialis release had significantly higher horizontal LPD than medial retinacular release. Vastus medialis release had the smallest increase statistically in vertical LPD, and vertical LPD did not differ significantly between medial retinacular and capsule release. Among lateral realignment techniques, the horizontal LPD was significantly higher in anti-rotational suture with retinacular imbrication than in retinacular imbrication alone, but the vertical LPD did not differ significantly between the two groups. Our findings indicated that vastus medialis release could decrease the medial tension on the patella without inducing patellar instability in dogs. Both medial retinacular and capsule release could increase patellar instability; moreover, medial retinacular release does not decrease the medial tension on the patella. Antirotational suture with retinacular imbrication provides more lateral tension than retinacular imbrication alone.

• Korean Journal of Veterinary Service
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• v.31 no.3
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• pp.375-384
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• 2008

This study was performed to establish the discrimination of the corpus albicans that were formed after normal parturition and abortion in Holstein, The corpus albicans were obtained from 504 cows and 506 heifers slaughtered in the Agricultural Cooperative's Livestock Products Joint Market of Seoul City from March 2007 to October 2007. The difference in a gross examination (morphology, fibrogenesis, deposit state, color, and size) among the fixtures that exist in their ovaries was investigated. All of the cows had corpus albicans in their ovaries: 423 cows (83.9%) had less than three corpus albicans, 81 (16.1%) had more than four. In the heifers, however, 463 (91.05%) had no corpus albicans, 39 (7.7%) had one, and four (0.8%) had more than two. In the types of corpus albicans 73.2% of the cows had oval-type, 14.4% had circular-shaped, 12.4% had irregular-type. In the aborted heifers, however, oval-type appeared in 88.6% and circular-shaped appeared in 11.4%, and no irregular-type was found. There was no significant difference in the fibrogenesis and size of corpus albicans between cows and aborted heifers. However, slight difference in the color of the corpus albicans was observed between two types. In conclusion, it is not easy to discriminate by gross examination of ovary between cows and aborted heifers in the slaughter house.

• Journal of Korean Society on Water Environment
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• v.26 no.3
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• pp.377-386
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• 2010

Introduction of TBELs into Korean environmental regulatory system for wastewater may require very careful considerations and appropriate modifications of the TBELs applied in US. The Korean regulations for wastewater are based on uniform regulatory criteria for wastewater effluent discharge and are quite different from the individual permit system in US. In addition, the toxic pollutants regulated in Korea are much less than those in US. Therefore, the effects of TBELs application on the pollutants reduction and the economic feasibility should be carefully assessed for different categories of wastewater sources. In this study, the applicability of TBELs for the industrial categories of Korea was discussed. The TBELs were derived for a sample category, the pulp paper paperboard manufacture, based on the previously reported analytical data from 52 facilities of the domestic pulp paper paperboard manufacture in Korea. It was suggested that the BAT effluent limitations were BOD 30 mg/L, $COD_{Mn}$ 40 mg/L, SS 40 mg/L, T-N 30 mg/L and T-P 4 mg/L and that the allowable effluent loads were $0.31{\sim}1.75kgCOD_{Mn}/ton$-products. Due to the limitation of insufficient data, there were difficult to obtain the important factors to derive more systematic and accurate limitation standards for the pollutants such as the 'Long Term Average (LTA)', the 'Product Normalized Discharge Flow (PNDF)', and the 'Variability Factor (VF)'. However, as the first trial of TBELs determination based on the all available analytical data reported, the procedure and the outcome of the study may provide valuable insight on application of TBELs in Korea.

• Korean Journal of Weed Science
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• v.2 no.2
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• pp.114-121
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• 1982

Sagittaria pygmaea Miquel is widely infested and is the most dominant perennial weed in paddy field in Korea. This study was carried out in order to clarify the factors influencing tuber production and the competition ecology. The tuberization capacity in the paddy field transplanted with the small seedlings of rice was higher than in the paddy field transplanted with the vigor seedlings of rice. The stage which rice plants were most damaged by S. pygmaea plants was the period from 31 to 37 days after transplanting. According to the increasing of Eleocharis acicularis Roem. in the condition of rice cultivation, the number of S. pygmaea plants was remarkably reduced. Small size tubers planted within deep soil produced less tubers than large size tubers did. The number of plants and tubers were remarkably increased under the high levels of fertilization. Phosphorus was essential as well as nitrogen for tuberization. And the tuberization capapcity was different with the organic matter content in soil and with the soil moisture.