• 한국가정과학회지
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• 제7권2호
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• pp.13-30
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• 2004

The purpose of this study was to investigate the status of teacher's perception about the nutrition education of elementary schooL The results of this study were as follows. Most of the teachers responded that nutrition education necessitate in curriculum of elementary school, the main reason for necessity of nutrition education was for proper growth, they thought starting period of nutrition education was to begin when children are in a kindergarten and a infant home. The perception for a suitable person to teach the nutrition education showed dietician, parents, class teacher and a related teacher in oder and the time of that is a related class, as a spare time at everyday, a special activity time, and service a meal in order. Importances of the contents of a nutrition education were proper eating habits, growth and nutrition, a food hygiene and a disease in order. Problems of elementary students' nutrition were a unbalanced eating, a ingestion a processing and instant food too much, lack of table manner, fatness and a weak child in order. The most of expected effects through the nutrition education were a good table habits and manners, the way of a efficient nutrition education were a need of link with parents, a need of link the dietician. a teacher's class and training in order. The average score of nutrition knowledge was 6.3$\sim$6.9 out of 10 and teachers of Gwangju scored more higher on nutrition knowledge than teachers of Jeonnam, as they arranged a dietician was so.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.287-290
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• 1989

Single-phase $YBa_2Cu_3O_{j-g}$ (YBC) ceramic samples were annealed at $700^{\circ}C$ under a flowing $O_2$ atmosphere for 0, 18, 36, 54 and 72. hours after sintering. The resistivities(p) and the critical current densities($J_c$) of the samples were measured in a temperature range 77 to 300 K by a four probe method, using silver paint contacts. The variations of the electrical properties with annealing time are explained in terms of flux pinning, percolation probability and randomness, and alignment of grains and twins.The anomalous increases in $J_c$ and $T_c$ observed in sample annealed for a relatively long time possibly due to alignment of grains and twins, may imply the occurrence of superconducting glass state in high-$T_c$ superconducting ceramic.

• 한국초전도ㆍ저온공학회논문지
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• 제18권4호
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• pp.5-8
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• 2016

We report on the fabrication and measurement results of the electrical transport properties of superconductor-normal metal-superconductor (SNS) weak links, made of PbIn superconductor and Au metal. The maximum supercurrent reaches up to ${\sim}6{\mu}A$ at T = 2.3 K and the supercurrent persists even at T = 4.7 K. Magnetic field dependence of the critical current is consistent with a theoretical fit using the narrow junction model. The superconducting quantum interference device (SQUID) was also fabricated using two PbIn-Au-PbIn junctions connected in parallel. Under perpendicular magnetic field, we clearly observed periodic oscillations of dV/dI with a period of magnetic flux quantum threading into the supercurrent loop of the SQUID. Our fabrication methods would provide an easy and simple way to explore the superconducting proximity effects without ultra-low-temperature cryostats.

• 대한인간공학회지
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• 제33권4호
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• pp.281-287
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• 2014

Objective: The objective of the study is to develop a portable assistance device to help elderly users reduce strain on the knee and leg muscle while the elderly are standing up. Background: The pose of standing up from a chair is a basic movement, but the elderly often have difficulty standing up due to their weak muscles. We focus on designing a solution that helps the elderly reduce physical problems and support them standing up. Method: This study consists of three parts. Part I explores the way to reduce the refrain of leg muscle while standing up from a chair. In the process of structural development, we found that the moment is minimized when user pushes down the armrests due to a decrease in the force acting on the center of mass. In part II, a user test of 20 participants was carried out to rank the order of comfort of two stimuli: the chair with fixed armrests and the chair with the four-link mechanism that we created-in three different ways; (1) to stand up without touching armrests, (2) to stand up by pushing down on fixed armrests, and (3) to stand up by pushing down on armrests and being supported by the mechanism. To examine the statistically significant differences among the rank means, a Friedman test was conducted. In part III, we analyze the results of the user test and interview feedbacks, focusing on establishing a design strategy from UPO and visualizing it in 1:1 scale. Results: In part I, we decided to develop the four-link mechanism. The bottom is lifted up as the link rises. In part II, based on the rank data, we empirically found that UPO was assessed as the most comfortable during the stimuli. The thigh angle is smaller and the bottom of UPO is separated from a seat. In part III, after assessing the results and feedbacks, we created a visualization strategy for UPO: light, friendly, and novel. Conclusion: The portable and non-mechanical UPO comprises a four-link system that lifts the user's hips while standing. It can help users avoid knee and leg muscle strain. Its universal design considers the elderly's difficulties. Application: In a future study, combining light and durable material in UPO is expected to increase its usability. And this study is an opportunity to design various types of standing assistance devices.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1161-1164
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• 2002

The position information of the rotor are required while the SRG(Switched Reluctance Generator) is drived. The position information is generally provided by shaft encoder or resolver. But it is weak in the dusty, high temperator and EMI environment. Therefore, It is required for the sensor to be eliminated from SRG. In this paper, a estimation algorithm for the rotor position of the SRG is introducted and a constant DC-link voltage is controled by PID controller. The estimation algorithm is imple--mened by using the instantaneous flux profile, and the initial position is estimated by injecting high frequency pulse voltage. It is proved that the rotor position is esti--mated very well by the exeriments.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.182-183
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• 2006

An electromagnetic memory effect observed in superconducting YBCO system was studied. From the measurement of differential conductance, it was cleared that the mechanism of electromagnetic memory can not be explained by using conventional flux flow model. By changing the density of external magnetic flux, changes m inductance of a coil in which a superconducting bar is inserted were also measured. It was concluded that the electromagnetic memory effect aries from the interaction between the trapped magnetic flux and the weak link of the filament formed in the superconducting bar.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
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• pp.1007-1013
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• 2003

It is becoming increasingly clear that participation in the 'new economy' driven by scientific and technological advances will be the way to achieve global prosperity in the 21st century. An analysis of the patents assigned to a particular country, using the techniques in this study, provides a means to objectively assess the potential for participating in that prosperity, and to identify strong and weak area in technological potential. The analyses are based on Korean-invented patents issued in the United States, and on the citation analysis techniques that link these patents with other patents.

• 한국공작기계학회논문집
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• 제17권6호
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• pp.56-62
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• 2008

An Allium-odorum is difficult material to handle because it is soft and weak mechanically. For bundling work of allium-odorum, we must grip in the bundle shape of unit weight. However it is difficult to grip allium-odorum by hand because the bundle bulk is very big. Especially, in packing work, the bundle shape of allium-odorum package is more important than other vegetables because the sale price depend on the bundle shape. In this paper, we propose bundling mechanism for a rectangular shape, and semi-auto bundling mechanism by a eccentric roller and a triangular link. We carry out mechanical model and analysis respectively using the CATIA V5 and SimDesigner. We have manufactured the prototype of the semi-automatic bundling machine, and got satisfied result through field test. This machine is in the process of commercialization.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.27-34
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• 2000

HTS wires processed by PIT method are now available for magnet applications. But, those wires can not be used over 40 K due to weak link. This leads to necessity of development of coated conductor which can retain high $J_c$ at high field in liquid nitrogen. In this paper, various technical issues and the R&D status for both PIT wires and coated conductor were discussed. The difference of coated conductor's processes were also investigated and summarized. Various requirements for a design of HTS magnets were discussed. Anisostropic $J_c$ property with respect to magnetic field was considered to determine the coil's critical current. Low n value is a critical parameter to degrade a field stability with respect to time for a persistent mode HTS magnet. The relation between the margin of operation current and n value was investigated. Prototype HTS magnets with PIT wires are being developed for various applications such as crystal growth, MRI, magnetic separator and etc. HTS magnets will come into wide use in various fields of industries if the HTS wires with a low performance cost is developed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.348-349
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• 2005

An electromagnetic memory effect observed in superconducting YBCO system was studied. From the measurement of differential conductance, it was cleared that the mechanism of electromagnetic memory can not be explained by using conventional flux flow model. By changing the density of external magnetic flux, changes in inductance of a coil in which a superconducting bar is inserted were also measured. It was concluded that the electromagnetic memory effect aries from the interaction between the trapped magnetic flux and the weak link of the filament formed in the superconducting bar.