• The Transactions of The Korean Institute of Electrical Engineers
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• 제60권7호
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• pp.1438-1443
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• 2011

The increase of power capacity in the superconducting fault current limiter (SFCL) is essential for application into the power grid. To achieve this, when superconducting units were connected in series and parallel, the unbalanced quenching characteristics between superconducting units generated by different critical current behavior should be improved. In the transformer-type SFCL, the superconducting units connected in series could be simultaneously quenched by the connection of neutral lines between secondary coils and superconducting units. From this the consumed power in superconducting units was equally distributed. In addition, the more the turn ratio of the transformer was reduced, the more consumed power in the superconducting units was reduced by the decrease of the induction voltage generated in the superconducting units. From those results, the transformer-type SFCL using neutral lines could increase the power capacity of the SFCL by the equal power division into the superconducting units.

• Computers and Concrete
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• 제23권2호
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• pp.97-106
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• 2019

This paper describes the design of a new interlocking masonry system, the production of designed interlocking units and mechanical properties of interlocked masonry assemblages with mortar. In this proposed system, units have horizontal and vertical locks to integrate the units to the wall and have a channel to enable the use of horizontal reinforcements in the wall. Using these units, unfilled, filled or reinforced walls can be constructed with or without mortar. In the production of the interlocking units, it was decided to use foamed concrete. 12 trial productions have been carried out at different mix proportions to obtain the optimum concrete mix. At the end of the mentioned productions, the units were produced with foam concrete which is selected as the most suitable in terms of compressive strength and specific gravity. Then, axial compression, diagonal tension and bed joint shear tests were carried out to determine the mechanical properties of the interlocked masonry assemblages with mortar. Results from the tests showed that interlocks designed to strengthen the system against shear stresses by creating discontinuity throughout the joints have been successful to achieve their aim. Obtained data will enable structural analysis of walls to be constructed with these new units.

• Journal of the Architectural Institute of Korea Structure & Construction
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• 제34권2호
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• pp.83-90
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• 2018

This study was conducted to investigate the living environment of semi-basement housing units in multi-household houses. It analyzed measurements of temperature and humidity obtained from the housing units. For this study, temperature and humidity sensors were installed in 10 semi-basement housing units to measure interior temperature and humidity for 13 months. A survey was conducted to get information about the occurrence of dew condensation and mildew and to investigate residents' satisfaction level with the residential environment. According to the result, all the housing units under study had dew condensation and mildew. The average summer temperature of the 10 housing units was $27.84^{\circ}C$, and average humidity was 64.91%RH, while the average winter temperature was $20.6^{\circ}C$, and the average humidity was 40.12%RH. Depending on the condition of each housing unit, deviation was big. Residents' average level of satisfaction with the living condition was 2.03 which shows a low satisfaction (on a scale of 1-5 with 5 being completely satisfied.).

• Journal of Agricultural Extension & Community Development
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• 제2권1호
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• pp.23-39
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• 1995

The purpose of this study was to explore a paradigm for the development agricultural cooperative unit in Korea. To fulfill the purpose of the study, both a review of literature and case studies was used. The agricultural cooperative units selected for the survey were Doduram Swine, Songtan Cooperative Organization, Okyung Cooperative Farms, and Harim Poultry Company. To identify major factors and limitations associated with effective management of agricultural cooperative units, selected cooperative units for production, processing and marking were surveyed and analyzed. This study identified four major factors to be included in a development paradigm of effective agricultural cooperative units which were: 1) active participation of farmers, 2) techniques end attitude of participants, 3) horizontal integration of a high technology enterprise with agricultural production, and 4) increasing cooperative work on production and marking within the unit. Based on the results of the study, the following recommendations were made for further improvement and development of agricultural cooperative units : First, farmers should be encouraged and motivated to participate actively in agricultural cooperative units. Second, participants of the agricultural cooperative units should be equipped with both technical knowledge and skills on agricultural production, processing and marking. Third, a national net-work system should be established for the agricultural cooperative units throughout the country. Fourth, agricultural cooperative units should be expanded to various agricultural sectors covering wider area. Finally, agricultural cooperative units should be supported by farmers, agricultural organizations and the government for more effective management and further development.

• Journal of the Korean Society of Radiology
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• 제4권2호
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• pp.31-35
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• 2010

In this study, we surveyed students recognition of the base units and radiation related units among international standard units, and determined the necessity of unit education. The survey was conducted using a questionnaire composed of 18 questions, and in the survey, students at the Radiology Department were asked about recognition and education. According to the results of the survey, around 44% of the students answered wrongly on base unit kV, and around 28% answered wrongly on km. Particularly with regard to the relation between units and numbers, around 57% of the students chose wrong answers. As to prefix mega and giga, respectively, 22% and 20% of the students chose wrong answers. To the question on radiation related unit Sv, around 30% gave wrong answers. Recognition of radiation related units was higher in senior students. To the question of whether to have received special education on units, over 50% of the students replied negatively. These results suggest the necessity of education on international standard units.

• The Journal of Korean Society for Radiation Therapy
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• 제5권1호
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• pp.47-56
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• 1992

This report presents the date obtained in a 1990 survery al radiation oncology identified by KSTRO. This study was done to find out the status of current use of the radation thrapy equipments, personnels, utilization of equipments and orther problems in the field of radiation oncology department in korea. Our discussion addresses the areas of regional imbalance in the distribution of megavolage units, buying and selecting the units, improving of quality in radiation treatments. There is increasing use of linear accelerators, simulators, treatment planning computers. The use of Cp-60 units has been prohressively decreasing. And slowly improving, numbers of physicians, physicists, and technologists when compared with the 1988. A total of 51 megavoltage units were identified, giving a ratio of 1.88 technologists/ megavoltage units. We treat average 23.0 patients by megavoltage units.

• The Journal of Advanced Prosthodontics
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• 제4권2호
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• pp.93-96
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• 2012

PURPOSE. The objective of this study was to compare the light transmittance of zirconia in different thicknesses using various light curing units. MATERIALS AND METHODS. A total of 21 disc-shaped zirconia specimens (5 mm in diameter) in different thicknesses (0.3, 0.5 and 0.8 mm) were prepared. The light transmittance of the specimens under three different light-curing units (quartz tungsten halogen, light-emitting diodes and plasma arc) was compared by using a hand-held radiometer. Statistical significance was determined using two-way ANOVA (${\alpha}$=.05). RESULTS. ANOVA revealed that thickness of zirconia and light curing unit had significant effects on light transmittance ($P$ <.001). CONCLUSION. Greater thickness of zirconia results in lower light transmittance. Light-emitting diodes light-curing units might be considered as effective as Plasma arc light-curing units or more effective than Quartz-tungsten-halogen light-curing units for polymerization of the resin-based materials.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.215-217
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• 2008

This paper deals with the structural vibration characteristics for an outdoor units support of an air-conditioner. Even though main noise sources are compressor noise and fluid noise which is caused by the fan, the structural modification of the outdoor units support may affect vibration and noise. In this paper, damping ratios for two kinds of an outdoor units support of an air-conditioner are measured through the modal testing. In order to reduce the structural borne noise due to an outdoor units support of an air-conditioner, four kinds of rubber materials are selected and tested.

• Journal of the Korean housing association
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• 제14권3호
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• pp.41-49
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• 2003

An evaluation of the environments in the wandering pathway of the dementia units was carried out. It is revealed that the quality of the environment for the wandering pathway of the sample units was very low. In particular, lacks of social environments in Unit-B and Unit-C, and lacks of orientation aids in all the sample units were shown. Therefore, re-design for the wandering pathway of the sample units is needed. Recommendations for improving the wandering pathway and having appropriate wandering pathway without any abrupt change in existing layout of the sample units were suggested, and the limits of this research is diagnosed. It is also shown that since evaluation categories used in this paper had very closed relationship each other, those evaluation categories can be used in other settings.

• Proceedings of the Korean Institute of Interior Design Conference
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• 한국실내디자인학회 2004년도 춘계학술발표대회 논문집
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• pp.66-70
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• 2004

With its rapid modernization and the unparalleled rate at which its society is aging, South Korea faces the need for a dramatic increase in its supply of nursing homes. Among the spacial components of nursing homes, residential units are considered as an essential part because the older person in nursing homes usually spend most of their time in residential units and the nursing homes are mainly composed of various residential units. It is necessary, therefore, to prepare a guideline for the plan of residential units in order to design the healthy and efficient nursing homes. This paper has first identified the concept of residential unit and analyzed 55 cases in the 51 nursing homes from 4 countries. On the basis of this analysis, architectural prototypes of residential units have been proposed and the architectural characteristics of them have been compared analytically.