• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1073-1074
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• 2011

The loss is most important problems for the practical applications of permanent magnet synchronous motor(PMSM). In this paper, rotor sleeve and stator shape design of high speed permanent magnet motor for loss reduction. First, this paper found optimum sleeve thickness for calculation eddy current loss on the basis of analytical method, because eddy current is influenced by conductivity of material and area. Then, stator shape design is changed as maintain same slot area for reducing stator core loss. Finally, this paper compared analytical result with optimum sleeve thickness obtained from finite element(FE) method, and stator core loss is calculated from FE method.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.10a
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• pp.268-268
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• 2017

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 1999.02a
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• pp.18-21
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• 1999

The effects of joining process such as contact method, shape of joined area and pressure on the properties of Bi-2223 superconducting tape have been optimized. In the process tapes were etched to expose the superconductor core in the shape of 'ㅁ' and 'ㄷ'. The exposed cores of the two tapes were brought into contact, uniaxially pressed and sintered. Subsequently, the current capacity of the joined tape was measured as a function of uniaxial pressure. It was observed that the current capacity was significantly dependent on uniaxial pressure. The joined tape, fabricated with a pressure of 1,600 MPa, showed the highest value of current capacity(90%) of highest value of current capacity is resulted from improvements in core density, contacting area and grain alignment, etc. In addition the effect of processing variables on microstructural evolution and mechanical property of joined tape will be presented.

• 연구논문집
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• s.27
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• pp.175-181
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• 1997

Superconducting joints between Bi-2223/Ag tapes are fabricated by a press & reaction anneal and a multiple press & anneal. The silver sheath was mechanically or chemically removed from one side of each tape without altering the superconducting core. The exposed superconducting core of the two tapes were brought into contact and pressed so as to form a lap joint. The joined tapes were then subjected to a series of different thermomechanical treatments to achieve optimum heat treatment condition. The result from transport measurements shows that critical current ($I_c$) transmitting through joined area reaches 9A, approximately 60% of the current capacity of the tapes themselves. The critical current through joined area was improved by repeated press and reaction annealing. Measurements of the current-voltage relationship were made with several configuration of the voltage probes to characterize the critical current variation and I-V curve along the joint. Also discussed are microstructural aspects of the superconducting joint.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.33-37
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• 2002

Recently, composites have been widely applied in the sporting goods, automobile, aerospace industry. As the use of advanced composites increase, specific techniques have been developed to repair damaged composite structures. In order to repair the damaged part, it is required that the material in the damaged area be removed first by utilizing the proper method, and prepreg be laid up in the area and cured under vacuum using the vacuum bagging materials. In curing process, either in an oven or autoclave is to be delamination can be occurred in the sound areas during and/or after the exposure to the elevated curing temperature in case that the repair process is repeated. Therefore, this study was conducted to evaluate the degree of degradation of properties of the cured parts and how it affects to the delamination phenomenon between laminated skin and honeycomb core.

• Journal of the Korean Institute of Rural Architecture
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• v.10 no.3
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• pp.67-74
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• 2008

The roles and needs for the greentourism facilities require the associated functions and systems which can be determined from considering the existing successful facilities. Some of successful examples for the greentourism facilities in Japan have been investigated, and their functions and systems carefully examined. This paper is intended to provide a meaningful step for introducing and applying the functions and systems for the greentourism facilities in Japan to Korea. The facilities should support the greentourism that leads to the active cultural exchange between urban and rural areas. The required specific facilities are discussed in this paper. For newly developed facilities, restaurants, specialty stores, and hotels may be effective facilities for the greentourism. The design for the entire greentourism facilities should consider, for the development of the area, the several kinds of required functions of the greentourism, such as the travel guide center, the marketing center, the information center, the business center, the human resources center, and the environment conservation center.

• 한국해양학회지
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• v.22 no.3
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• pp.119-129
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• 1987

Sediments in the cores from the KONOD-1 area consist mainly of authigenic smectite and clinoptilolite, and terrigenous minerals of illite, chlorite, kaolinite, quartz, and plagioclase. The authigenic minerals become dominant over the terrigenous minerals with increasing depth. Clinoptilolite occurs at the deeper core depth because its formation is slower than that of smectite. The vertical distribution of minerals indicates that the eolian influence, probably in the late Oligocene, diluted the abundance if smectite in near-surface sediments. This vertical distribution pattern may also have been affected by progressive dissolution of authigenic minerals in the near surface sediments.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.11
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• pp.2017-2022
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• 2007

In a memory, most power is dissipated in line of high capacitance such as decoder lines, word lines, and bit * lines. The decoder size as well as the parastic capacitances of the bit-line are going to reduce, if ROM core size reduces. This paper proposes to reduce a mathod of power dissipation for reducing ROM core size. Design result of ROM used in FFT[2], proposed method lead to up to 40.6%, 42.12%, 37.82% reduction in area, power consumption and number of Tr. respectively compared with previous method.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2002.11a
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• pp.79-84
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• 2002

Many people think, in common that An expansion toward outer city is a development, and it can be a general trends in a new development in a growing city. But We can see many case which moving of a public building are considerate as a core element to promote the new development towards outer city, and that is a negative element of slum in central area and community making. There are many aspects to pursue sustainable urban structure of in a city, and public building is a very important element to manage deteriorate central area from social slum in a old town. In this presentation, three project, Local Authority office of Chonnam province, Kwangju Station, and Hyper Urbanity, and it shows sustainable concept of the public building as a core in a city development. The effect of the projects are expected sustainable development and community in terms of social, cultural and historical aspects.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1109-1118
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• 2021

The construction of STELLA-2 facility is on-going to demonstrate the safety system of PGSFR and to provide comprehensive understanding of transient behavior under DBEs. Considering that most events are single-phase natural circulation flow with slow transient, STELLA-2 was designed with reduced-height of 1/5 length scale. The ratio of volume to surface area in the vessel can relatively increase resulting in excessive heat transfer. Therefore, a steady-state thermal-hydraulic analysis was performed and the effect of design change to reduce the heat transfer through redan was investigated. The heat transfer through single wall redan in STELLA-2 was 3% of the core power, comparable to 1% of the core power in PGSFR. By applying the insulated redan, about 70% of decrease effect was observed. The effect on transient behavior was also evaluated. The conclusion of this study was directly applied to the STELLA-2 design and the modified version is under construction.