• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.457-460
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• 1998

Present paper is devoted to the brief analysis of the present state and the prospects for the future of technology of the high frequency devices and high speed integrated circuits based on the $A_{3}B_{5}$ semiconductor compounds, including the $A_{3}B_{5}$-heterostructures, in the republics of the former USSR. tunneling quantum well-structures were widely used.

• The Mathematical Education
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• v.42 no.3
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• pp.265-274
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• 2003

To learn number system is a basic thing in school mathematics. In this paper, we analyze how number system is introduced in the 7th national curriculum and text books according to it. We found that the method of introducing number system is quite different from the former curriculum and former text books. There are many negative effects on the transition when compared with those of United States of America. There are many gaps between elementary school mathematics and middle school mathematics about levels and skills to deal with numbers. It is desirable to distinguish the negative sign from subtraction and to keep the concepts of commutativity and associativity of operations from the beginning. We also suggest to change the introducing timing and extension methods of number system in 7th grade mathematics.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.1-4
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• 2004

RC column bent piers represent one of the most popular piers used in highway bridges. Seismic performance of reinforced concrete (RC) column-bent piers under bidirectional seismic loadings was experimentally investigated. Six column bent piers were constructed with two circular supporting columns. Test parameters are different transverse reinforcement and loading pattern. Three specimens were loaded with bidirectional lateral forces which were main cyclic loads in the longitudinal direction and subcyclic loads in the transverse direction. Other three specimens were loaded in the opposite way. Test results indicated that lateral strength and ductility of the latter specimens were bigger than those of the former specimens. Plastic hinge was formed with the spall of cover concrete and the fracture of the longitudinal reinforcing steels in the bottom part of two supporting columns for the former three specimens. Similar behavior was observed in the top and bottom parts of two supporting columns for the latter three specimens.

• Journal of information and communication convergence engineering
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• v.5 no.1
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• pp.23-28
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• 2007

In this paper, we propose ATM switch structure including AAL type 2 switch which can efficiently transmit low-bit rate data, even if the network has many endpoints. We simulate the architecture of ATM switch fabric that is modeled in computer program and analyze the performance according to offered loads. ATM switch proposed in this paper can support cell switching for all types of AAL cells which consist of AAL type 1, AAL type 2, AAL type 3/4, and AAL type 5 cells. We propose two switch fabric methods; One supports the AAL type 2 cell processing per input port, the other global AAL type 2 cell processing for every input port. The simulation results show that the latter is superior to the former. But the former has a strong point for easy implementation and extensibility. The proposed ATM switch fabric architecture is applicable to mobile communication, narrow band services over ATM network.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.157-160
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• 2004

In this paper, we measured the electrical and optical characteristics of an electrodeless fluorescent lamp system as product from the inside and outside of the country and compared the measured data. Output current wave of domestic 85W is unstable than it's of QL 85 W and the former of spend time after discharging and output current value is larger than the latter. Moreover optical characteristics(brightness, flux, efficiency) value of the former is small than the latter but color rendering index is equivalent. In conclusion, if we improve a little more quality then we must secure the superiority in competition.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.14 no.2
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• pp.1-12
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• 2010

The form of intermittent pulse(代脈) has three standards. The first is "The persistence of the pulse stop(止不能還)". This standard is extensively accepted to the medical scientists in every ages of after the . The second is "The replacement of the former pulses(更代)". This standard is very useful to explain the situations that the intermittent pulse(代脈) is regarded as a dead pulse(死脈). The third is "The regular inerval of the pulse stop(止有定數)". This standard is impractical and illogical to practical using of the intermittent pulse(代脈). The reason is misreading on the of Wang-Suk-Hwa(王淑和) and the inexact & expansive reproduction of medical men of the Myeong-Chung dynasty(明淸代).

• Proceedings of the Korean Institute of Interior Design Conference
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• 2005.10a
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• pp.171-175
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• 2005

The Principle of space composition in modern architecture is thought about functionalism that based on function and program but the present age attempt that escapes form of former space composition. The present age brings fast development than former ages, so we need the space which has correct flexibility on New Age for escaping in existing structural formality. Specially, the space that boundary of existing plate, column and wall is crumbled as becoming possible technological support with social backgrounds. What this study saying is the analysis about the relation between the concept of topology and the consecutive space composition. Therefore, there is the purpose understanding a characteristic of continuity of the plate through the topological concept and understanding the roll in interior space.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1210-1212
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• 2005

High temperature superconducting(HTS) power cable system consists of HTS cable, termination and cryogenic system. And the HTS cable consists of the former, HTS phase conductor, electric insulation, HTS shield and cryostat. Taking the advantage of HTS shield, the cold dielectric has been adopted. The phase conductor and the shield have been designed to minimize the AC loss below 1W/m/phase. The former has been designed to transport the fault current of 25kA, at fault condition. This paper describes the design process of 22.9kV HTS cable considering AC losses at normal state and the stability at fault condition.

• Journal of radiological science and technology
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• v.13 no.1
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• pp.19-24
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• 1990

In appilcation of wide latitude HR-C film to chest x-ray examination, former x-ray diagnosis area is larger and diagnostic information has great deal of promotion. HR-C film is compare to former x-ray film is larger latitude and density level is small, reading is very easily. Especially, high estimate that is in characteristic curve linearity of toe part is good, contrast of low density made good shape and not good describe to overlap is diagnostic information increase mediastinum portion etc.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.6
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• pp.143-149
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• 2008

This paper presents the results of the study on the novel micro mixer. Existing micro mixer is classified as active mixing and passive mixing by the mixing principles. Both mixing principles have problems. For solving these problems, this research has developed the novel micro mixers based on a totally different principle compared with former mixers. They not only have a simpler structure than former ones but also are able to achieve high mixing efficiency in spite of low power consumption due to using Lorentz Force. In addition, they are designed to increase the efficiency of mixing by changing the rotating direction of fluid with a polar switching circuit. Driving forces of the mixer are Lorentz force and a moving force of fluid due to electrophoresis. Because the efficiency of mixer is affected by electrode shape, several models have been made. The computer simulation has been made to estimate the efficiency of each mixer.