• Journal of the Korean Home Economics Association
• /
• v.41 no.11
• /
• pp.95-111
• /
• 2003

The purpose of this study was to investigate the current trend of early education and to examine the relationship between the state of early education and maternal beliefs, stress, and achievement pressure. The subjects were 275 mothers of 4∼6 year-old children in Seoul. The main results were as follows : 1) Most of the subjects' children(87.6%) were involved in early education, especially in the form of home-visit study and study papers. 2) Parental beliefs (about child development and early education) and maternal achievement pressure were significantly related to the degree of actual involvement and perceived necessity of early education. 3) Parental stress regarding child's temperament was significantly related to the starting age of early education. But the other factors of parental stress had no significant relation to the state of early education.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1996.05a
• /
• pp.6.1-10
• /
• 1996

Starting from the Debye theory of rotational Brownian motion equation, we derive an expression for explaining the generation of Maxwell displacement current (MDC) across single monolayers on a material surface. The orientational order parameter and the dielectric relaxation the of monolayers are derived. Based on fille analyses developed here, we examine the MDC across phospholipid monolayers with thermal stimulation due to the change in the spontaneous polarization, and the generation of MDC from 4-cyano-4\`-5-alkayl-biphenyl(5CB) Langmuir-film at the onset of transition by monolayer compression

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1988.05a
• /
• pp.17-19
• /
• 1988

$YBa_2Cu_3O_{7-x}$ oxide superconductors were fabricated by the hot isostatic pressing (HIP). It was shown that their structures were orthorombic and constited of a single (123) phase. While as-sintered compacts had many pores, they were remarkably reduced by Hiping. The on-set and off set temperature of (123) compound sintered at $950^{\circ}C$ in oxygen and hiping at $880^{\circ}C$ were the highest and it showed 0 resistance at $90^{\circ}K$. The critical current density ($J_c$) of the above superconductor was $27A/cm^2$ and it also showed a number of twin structures, which are typical of high $T_c$ superconductor. It seemed that the low current density may be due to the many pores of starting-sintered compacts.

• Progress in Superconductivity
• /
• v.1 no.1
• /
• pp.56-60
• /
• 1999

Ultra fine MgO particles added BSCCO tapes were fabricated by tape casting using Doctor Blade Method and enclosed by silver foil for different starting compositions (that is, 2223 major, 2212 major). In order to obtain optimum microstructure, thermomechanical treatment was done. Microstructure and phase were analyzed by XRD, SEM and DTA. The critical current density was measured under magnetic field at 77K. The tapes fabricated from the precursor powder with BSCCO-2223 phase (>90%) result in a microstructure with a larger grain size and higher transport critical current density value under magnetic field at given thermomechanical treatment conditions.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.313-314
• /
• 2006

Indicating product quantity by real time can be benefit both worker and management. Worker can compare real product quantity with its target and can adjust working speed to match with goal. Therefore, so called JPH equipment developed to indicate target quantity of product. As a main processor PIC16F877 was used and FND display were used to indicate current time, elapsed time, JPH value and target amount of product. Values like JPH and starting time, etc. are can easily be set by $4{\times}4$ numeric keypad and display datum likes target amount of product, current time and elapsed time, etc are displayed on FND by RS232 serial transmit. The operation of JPH equipment are tested and verified through long term test and are proved acting properly on working conditions.

• Management & Information Systems Review
• /
• v.8
• /
• pp.129-146
• /
• 2002

This study reviews an overview of the current tax support system in Local Tax Law for venture company. And this study provides the directions for developing tax support system in Local Tax Law related policy for the venture company in Korea. The tax authority provides a supporting directions of venture company in three ways: a financing viewpoint, a technical and manpower viewpoint, and the location viewpoint. And the supporting system for venture company is devide into tax support system through tax laws and support system through other law. The requirements of receiving tax supporting for venture company in Local Tax Law are a venture company, a small and medium company, a newly starting firm, and so forth. To mitigate the restriction imposed by the current tax law on venture company encourage venture activities in Korea.

• Proceedings of the KSR Conference
• /
• 1998.05a
• /
• pp.458-465
• /
• 1998

This paper presents an inverter-driven induction motor used as the traction motor for a high speed drive system that is required safety, reliability and performance and so on, In the respect of traction motor design, it is mainly showed the weight reduction inclination and characteristic investigation due to V/f driving pattern variation of inverter. Particularly, the reduction of V/f ratio pattern effects on the weight of traction motor and badly on the increase of phase current of traction motor in starting point. This method of weight reduction design have to be reached the decision with not only motor but also the consideration of inverter system because of the heat capacity, weight and material cost of inverter according to the increase of current.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1998.06a
• /
• pp.367-370
• /
• 1998

In this paper, based on the research of high temperature YBCO superconductor, using the Yb instead of Y, with the YbBCO superconductor powder which was combined by means of conventional solid reaction, textured directional crystal was prepared by MCP method and the character was analyzed. Mixing the starting elements and calcining at 890$^{\circ}C$, 900$^{\circ}C$, 910$^{\circ}C$, single phase YbBCO, Yb$_2$BaCuO$\sub$5/ and BaCuO$\sub$2/ were certified. And from the powder which was calcined at 900$^{\circ}C$ the, sample which became texture-growth by MCP method was well oriented. The result of DTA measurement, the fusing point of YbBCO superconductor and it\`s critical current was measured to be 979$^{\circ}C$, 87K respectively. The critical current density was obtained at the value of 700A/$\textrm{cm}^2$(77K. 0H) calculated by Bean's Model using the measured hysteresis curve of VSM.

• Management & Information Systems Review
• /
• v.4
• /
• pp.443-467
• /
• 2000

This study reviews an overview of the current tax support system for venture company and provides the directions for developing tax support system related policy for the venture company in Korea. The tax authority provides a supporting directions of venture company in three ways: a financing viewpoint, a technical and manpower viewpoint, and the location viewpoint. And the supporting system for venture company is devide into tax support system through tax laws and support system through other law. The requirements of receiving tax support for venture company are a venture company, a small and medium company, a newly starting firm, and so forth. To mitigate the restriction imposed by the current tax law on venture company encourage venture activities in Korea.

• Journal of Electrical Engineering and Technology
• /
• v.5 no.1
• /
• pp.140-145
• /
• 2010

The monitoring and the diagnosis of the faults in induction motors starting from the stator current are very interesting, since it is an accessible and measurable quantity. The spectral analysis of the stator current makes it possible to highlight the characteristic frequencies of the faults but in a wide frequency range depending on half the sampling frequency, making it very difficult to monitor on-line the faults. In order to facilitate the use of the relevant frequencies of machine faults we proposed the extraction of the frequency components using two methods, namely, the amplitude and the instantaneous frequency. The theoretical bases of these methods were presented and the results were validated on a test bench with an induction motor of 5.5 kw.