• Nuclear Engineering and Technology
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• v.49 no.1
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• pp.54-70
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• 2017

The accumulator is a passive safety injection device for emergency core cooling systems. As an important safety feature for providing a high-speed injection flow to the core by compressed nitrogen gas pressure during a loss-of-coolant accident (LOCA), the accumulator injects its precharged nitrogen into the system after its coolant has been emptied. Attention has been drawn to the possible negative effects caused by such a nitrogen injection in passive safety nuclear power plants. Although some experimental work on the nitrogen injection has been done, there have been no comparative tests in which the effects on the system responses and the core safety have been clearly assessed. In this study, a new thermal hydraulic integral test facility-the advanced core-cooling mechanism experiment (ACME)-was designed and constructed to support the CAP1400 safety review. The ACME test facility was used to study the nitrogen injection effects on the system responses to the small break loss-of-coolant accident LOCA (SBLOCA) transient. Two comparison test groups-a 2-inch cold leg break and a double-ended direct-vessel-injection (DEDVI) line break-were conducted. Each group consists of a nitrogen injection test and a nitrogen isolation comparison test with the same break conditions. To assess the nitrogen injection effects, the experimental data that are representative of the system responses and the core safety were compared and analyzed. The results of the comparison show that the effects of nitrogen injection on system responses and core safety are significantly different between the 2-inch and DEDVI breaks. The mechanisms of the different effects on the transient were also investigated. The amount of nitrogen injected, along with its heat absorption, was likewise evaluated in order to assess its effect on the system depressurization process. The results of the comparison and analyses in this study are important for recognizing and understanding the potential negative effects on the passive core cooling performance caused by nitrogen injection during the SBLOCA transient.

• Journal of Gifted/Talented Education
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• v.25 no.5
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• pp.749-765
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• 2015

This study is aimed at validation of the Korean Version of the Perfectionism Inventory which was developed by Hill et al.(2004). To do so, exploratory factor analysis and confirmatory factor analysis with 167 science high school and 161 middle school gifted students were conducted. It appeared 6 factor structure consisting of 'Self-Evaluative Perfection Strivings', 'Parental Pressure', 'Planfulness', 'Striving for Excellence', 'High Standards for Others', and 'Organization', which does not support 8 factor of the original scale. As a result, Cronbach's ${\alpha}$ ranged from .78 to .92 for subscale of PI and .93 for the total scale. The fit of measurement model was found to be ${\chi}^2=1257.618$ (df=792, p=.00), TLI=.903, CFI=.911, RMSEA=.047, indicating most of fit indexes were acceptable. Also, the validity of the scale was examined by the correlations between the PI and MPS. PI Korean version is significant to confirm the factor structure and validity of perfectionism which was influenced by characteristics of gifted students and Korean culture. These results show that the PI is quite reliable and valid tool for measuring perfectionism for gifted students.

• Journal of Life Science
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• v.26 no.6
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• pp.651-656
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• 2016

Bee pollen is produced by honeybees and is considered one of the most balanced and nourishing nutritional supplements available. Historically, bee pollen has been prescribed for its healing properties and consumed for its high-energy supply. Recent research has provided evidence that bee pollen has diverse biological activities, such as anti-oxidant, anti-inflammatory, anti-bacterial, and even anti-cancer effects. However, the outer membrane of the pollen grain, exine, is highly resistant to most acidic solutions, high pressure, and even digestive enzymes, and the resulting low bioavailability limits its nutritional and clinical applications. This study applied a wet-grinding method to destroy the exine effectively, and it then examined the pollen's enhanced biological activity. First, microscopic observations provided strong evidence that wet grinding destroyed the exine time-dependently. In addition, the content of polyphenols, well-known ingredients of bee pollen and used as internal standards for the quality control of commercial pollen preparations, increased up to 11-fold with wet grinding. Further, the anti-oxidant activity demonstrated on the ABTS anti-oxidant assay, as well as the DPPH radical scavenging assay, was also dramatically increased. Together, the results presented here support a new technology by which bee pollen can be used as a resource for medical, nutritional, and cosmetic applications.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.510-516
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• 1995

A multidisciplinary weight control program was conducted for obese women. The major components of the program included low calorie diet therapy, exercise, behavior modification and nutritional education and counseling. Sixteen healthy volunteers in excess of body fat, above 30%, were enrolled in the group support program. But 5 person were dropped out in the 2nd week of treatment. During the 1st week of group orientation, individual cause of obesity was assessed through a computer program including survey of dietary intake, activity, eating habits and life styles. During the 5 weeks of treatment, 4.8kg of average weight loss was accomplished using a following program ; low calorie diet(1200kcal/day with all essential nutrients), low impact aerobic exercise(50~60% of $VO_{2max}$, 1 hour/day in a group, 3~5 days/week), behavior modification of individual life styles and eating habits causing obesity and nutritional education concerning nutrition, role of exercise such as brisk walking, importance of slow eating in regular meal pattern and internal motivation for weight reduction, health risk of obesity and rapid weight loss, weight recycling and yo-yo syndrome, etc. Nutritional conseling was conducted 3 times per week with checking self-records of foods, activity, emotional state and tiredness. Before and immediately after 5 weeks of treatment, blood pressure, fasting blood glucose, cholesterol and triglyceride were measured and comparied with paired t-test. After 5 weeks of treatment, body weight, body mass index, body fat and circumferences of waist, upper arm and hip were significantly decreased. Also LDL-cholesterol was significantly decreased after obesity treatment.

• Korean Journal of Construction Engineering and Management
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• v.16 no.6
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• pp.101-111
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• 2015

The modular construction method has been getting more attention followed by global eco-friendly trend as the domestic construction industry has focused more on remodeling and extension work. The modular construction method is an industrialized construction system which is not likely as the existing construction method it manufactures more than 70% modules at the factory then assembling can be completed in a short amount of time on site. The modular construction method has various strengths; shortening of construction period by on-site work decrease, weight pressure reduction by usage of light steel frames and cost saving by repetitive manufacturing. However, it is currently not expanded due to the existing commercialized construction method. Therefore, this research is in order to help the related authorities make decisions to select the construction method and motivate expansion of modular construction method which can be utilized effectively in the extension works. The intention of this research is to stress differentiation from other construction methods in construction period, construction expenses, labor and forces by comparing and analyzing actual cases, to inform competitiveness of modular construction method by concrete effect analysis and to support adoption of the modular construction method into the domestic industry.

• Journal of Pharmacopuncture
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• v.18 no.1
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• pp.63-71
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• 2015

Objectives: This study was carried out to analyze the single-dose toxicity of Eun-Bi San pharmacopuncture injected into the muscle of Sprague-Dawley (SD) rats. Methods: All experiments were performed at Biotoxtech, an institution certified to conduct non-clinical studies under the Good Laboratory Practice (GLP) regulations. Six week old SD rats reared by ORIENTBIO were chosen for this pilot study. The reason SD rats were chosen is that they have been widely used in safety tests in the field of medicine, so the results can be easily compared with many other databases. The Eun-Bi San pharmacopuncture was made in a clean room at the Korean Pharmacopuncture Institute (KPI, K-GMP). The constituents of the Eun-Bi San pharmacopuncture are Angelicae gigantis radix, Strychni semen and Glycyrrhizae radix. These were extracted at low temperature and low pressure in an aseptic room at the KPI. Doses of Eun-Bi San pharmacopuncture, 0.25, 0.5 and 1.0 mL, were administered to the experimental groups, and a dose of normal saline solution, 1.0 mL, was administered to the control group. This study was performed under the approval of the Institutional Animal Ethics Committee of Biotoxtech Co., Ltd. Results: No deaths or abnormalities occurred in any of the four groups. No significant changes in weight, hematological parameters or clinical chemistry between the control group and the experimental groups were observed. To determine if abnormalities existed in any organs and tissues, we used microscopy to examine representative histological sections of each specified organ; the results showed no significant differences in any of the organs or tissues. Conclusion: The results of this study suggest that treatment with Eun-Bi San pharmacopuncture is relatively safe and that its clinical use may be beneficial. Further evaluations and studies on this subject will be needed to provide more concrete evidence in support of these conclusions.

• Journal of Conservation Science
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• v.31 no.1
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• pp.75-86
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• 2015

A scale Armor is usually excavated in a scattered form weakened by corrosion after its burial. Therefore, they should be brought into the indoor in a safe environment for the on-site conservation treatment as it was excavated. They should be placed on a stable support with a reinforced base in the indoor treatment. In this process, the bottom surface which can not be observed after the conservation treatment is placed for a record by actual survey and photography. But this method had a limit on figuring out the whole aspects of the artifact. For compensating the defect, duplication of the artifact was considered as an alternative method for the previous two methods in the case of conservation of the scale Armor from Jinyoung 2-Area, Gimhae. Neck guard was excavated in a distorted form by the earth pressure, and was hard to recognize the original shape. However, whole real material of its original form was secured through the combination of each duplicated lamellae. Throughout the application of the duplication technique in the process of conservation of scale Armor and neck guard, it could secure the real material of the bottom surface and elevate the understanding of the artifact. Moreover, a constitution of the armor could be identified more effectively.

• Journal of the Korean Society of Hazard Mitigation
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• v.2 no.4 s.7
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• pp.131-141
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• 2002

Precast concrete (PC) panels are often used as retaining walls to support soil pressure. In such a case, the panels should be connected at the location where PC panels meet with a buttress. However, it is not easy to provide enough development length for the reinforcing steels due to the limited width of the buttress. If it happens, the width of buttress should be increased as large enough although it is not desirable. The critical section required for providing the development length is always located where the flexural moment is maximum. Thus it is the place the buttress width ends. Also it is the place that the reinforcing steels stressed to maximum. However, it is possible to make differentiate between the maximum moment location and the most stressed location of reinforcing steels. It means that the most stressed location of reinforcing steels, the critical section, can be moved to the other place where the moment is not maximum. New critical location will have less moment than that of buttress width ends. In consequence, the development length would be longer than that of the typical way of construction. Debonding or cutting technique make it possible to reduce the moment strength of a section. Therefore reinforcing steels are debonded or cut to have a desired flexural strength at a desired place. In this study, five test specimens in full scale were erected to examine the effects of critical section movement in PC panel joints. Test parameters were the length variations of debonded and cut reinforcing steels. The test results showed that the debonding or cutting technique could be used to lengthen the development length in the joint of PC panels.

• Cartoon and Animation Studies
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• s.25
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• pp.41-63
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• 2011

Many educational facilities have been formed due to the nation's revival policy in the animation industry since about 1995. Owed to the active financial support of the nation, the production industry rapidly vitalized, production technology rapidly advanced, and a large workforce is being passed on into society through educational institutions. The reality of many developing countries appearing to be putting emphasis on the industrialization of animation, similar to our country, is becoming a great pressure on us industrially. It is never easy to develop a certain field into a globally competitive industry in a short period of time. Our countermeasure, pursuant to these international circumstances, lies in innovation and creativity that has broken away from the existing methods of production, and mass production of high quality animation specialists. This paper is a new educational proposition for the consolidation of national competitiveness. Animating, the core of producing an animation, completely depends on the animator's artistic and technical ability. In order to supplement the existing methods of studying by theory and make up for the biggest weak point, which is the lack of "on the scene" learning contents, I propose incorporating movements based on frequently appearing characters in popular animations and acting them out slowly and including the "Slow Motion" kinetic effect, a way of enabling someone to learn and sense astrodynamic fundamental principles by oneself. It is a new method of learning movement, a plan made to achieve sensual performance gestures, and an improvement in direction for students who wish to become animators in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.160-166
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• 2018

The worldwide semi-conductor market has been growing for a long time. Manufacturing lines of semi-conductors need to handle several types of toxic gases. In particular, they need to be controlled accurately in real time. This type of toxic gas control system consists of many different kinds of parts, e.g., fittings, valves, tubes, filters, and regulators. These parts obviously need to be manufactured precisely and be corrosion resistant because they have to control high pressure gases for long periods without any leakage. For this, surface machining and hardening technologies of the metal block and metal gasket need to be studied. This type of study depends on various factors, such as geometric shapes, part materials, surface hardening method, and gas pressures. This paper presents strong concerns on a series of simulation processes regarding the differences between the inlet and outlet pressures considering several different fluid velocity, tube diameters, and V-angles. Indeed, this study will very helpful to determine the important design factors as well as precisely manufacture these parts. The EP (Electrolytic Polishing) process was used to obtain cleaner surfaces, and hardness tests were carried out after the EP process.