• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.730_731
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• 2009

고온초전도 마그넷은 저온초전도 마그넷과 달리 초전도선의 형태로 인한 이방성 때문에 마그넷의 형상에 따라 특성이 달라진다. 본 연구에서는 팬케이크 권선형 고온초전도 마그넷의 형상을 결정하는 요소 중에서 팬케이크 권선 사이의 공극 변화에 따른 특성을 계산하였다. 계산결과 최대의 중심자장을 발생하는 최적의 공극이 있음을 확인하였으며, 공극을 둠으로써 자장의 균일성도 향상됨을 확인하였다.

• 한국초전도학회:학술대회논문집
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• v.13
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• pp.91-91
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• 2003

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.41-44
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• 2003

We manufactured double pancake type windings with BSCCO wire for 1MVA HTS transformer. To verify cracks of HTS wire and performance of manufactured windings, the transportation current was measured. In this paper, we present result of the transportation current test as a DC current and compare a drop of current performance of HTS wire due to tension and rounding during the manufacturing with technical data. We obtained good results and this will be useful for another manufacturing of HTS winding

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.943-945
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• 2002

This paper presents conceptual design and 3-D electromagnetic analysis of 1MVA transformer with BSCCO-2223 High Tc Superconducting (HTS) tapes. The rated voltages of each sides of the transformer are 22.9 kV and 6.6 kV, and double pancake windings were adopted. High voltage and Low voltage sides were composed of several double pancake windings. Four HTS tapes were wound in parallel for the windings of low voltage side and were transposed in order to distribute the currents equally in each conductor. The transformer core was designed as a shell type core made of laminated silicon steel plates and the core is separated with the windings by a cryostat with Fiberglass Reinforced Plastics(FRP). A sub-cooling system using $LN_2$ were designed to maintain the coolant temperature of 65K. Finally perpendicular components of magnetic field applied to tapes were calculated 0.24T in the rated operation using 3-D analysis. A real 1MVA HTS transformer will be manufactured in near future based on the design parameters presented in this paper.

• The Journal of Korean Association of Computer Education
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• v.17 no.2
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• pp.115-124
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• 2014

Hypercube and star graph are widely known as interconnection network. The embedding of an interconnection network is a mapping of a network G into other network H. The possibility of embedding interconnection network G into H with a low cost, has an advantage of efficient algorithms usage in network H, which was developed in network G. In this paper, we provide an embedding algorithm between HCN and HON. HCN(n,n) can be embedded into HON($C_{n+1},C_{n+1}$) with dilation 3 and HON($C_d,C_d$) can be embedded into HCN(2d-1,2d-1) with dilation O(d). Also, star graph can be embedded to half pancake's value of dilation 11, expansion 1, and average dilation 8. Thus, the result means that various algorithms designed for HCN and Star graph can be efficiently executed on HON and half pancake, respectively.

• Korean Journal of Community Nutrition
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• v.7 no.5
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• pp.715-723
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• 2002

In recent yearn, eating habit that is not right causes disease the dietary fiber (DF) intakes of Korean decreases. Occurrence of chronic disease such as constipation increased gradually. This study was performed to investigate of high fiber standard recipes for one day including major source of DF such as vegetables, cereals and grain products, seaweeds, fruits, fungi and mushrooms, and legumes and products for improving constipation through dietary treatment. Nutrient analysis per person marked energy, protein, fat and DF content. The food of high I : S ratio (Insoluble fibers: Soluble fibers) are soybean sprout salad, rice gruel with vegetables, pan fried mushroom with vegetables. The food of low I:S ratio are fermented soybean paste stew, fried rice with kimchi, fruits salad with yogurt dressing and seasoned noodle with vegetables. The representative high fiber diet menu is rice gruel with vegetable, rice with radish and oyster, fermented soybean paste stew, kimchi stew, assorted soybean sprout salad, three kinds of pancake roll, pan fried mushroom with vegetables, fruits salad with yogurt dressing and seasoned noodle with vegetables. The menu developed in this study, contains fiber of at least 8.97 times of RDA and in point view of 1 day intake, that is similar to the scope of RDA, 20-25 g per day. This findings should be appliable to nutritional education and medical food for constipation. And also, the aim of study is constipation patients easily applicate that developed the food of high fiber using Korean common food. And the result of the study will be the basic data about clinical test of food developed in this study and the danger of high fiber diet. The representative high fiber diet menu is rice gruel with vegetable, rice with radish and oyster, fermented soybean paste stew, kimchi stew, assorted soybean sprout salad, three kinds of pancake roll, pan fried mushroom with vegetables, fruits salad with yoghurt dressing and seasoned noodle with vegetables. This findings should be applicable to nutritional education and medical food for constipation.

• Progress in Superconductivity
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• v.5 no.1
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• pp.61-64
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• 2003

In HTS transformer with double pancake windings, the perpendicular component of leakage magnetic flux density ($B_{r}$ ) applied to HTS tapes of double pancake windings of HTS transformer acts as a cause to decrease the critical current in HTS tape. So, in this paper, HTS transformer with reciprocal arrangement winding is designed. And in order to investigate the$ B_{r}$ applied to HTS windings, the 2-D non-linear electromagnetic analysis of HTS transformer is performed by using the OPERA 2D. The maximum $B_{r}$ applied to winding of HTS transformer is 0.112 T and the characteristics of HTS transformer were also obtained. But in this type of winding arrangement, reciprocal arrangement, the generated ac-loss to the HTS windings is very high because of the applied $B_{r}$ to HTS windings. Therefore, in order to reduce the generated ac-loss to the HTS windings, the new design of HTS transformer with concentric winding arrangement is presented in this paper and the 2-D non-linear electromagnetic analysis and the ac-loss for HTS transformer with the concentric winding arrangement is also carried out.

• Journal of the Korean Society of Food Culture
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• v.20 no.6
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• pp.744-753
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• 2005

This study was carried out to investigate Chinese in Beijing and Shanghai perception and preference for Korean Kimchi. The results were as follows: A questionnaire was examined on male 145(45.7%) and female 172(54.3%) of residing in Beijing, and on male 139(49.5%) and female 142(50.5%) of residing in Shanghai. In foods of eating with Kimchi resulted the highest Chinese foods 40.3% on male, and Korean. Chinese foods 25.3% on female in Beijing(p< .05), Korean, Chinese foods 26.7% and 25.3% on male respectively, and Korean foods 50.7% on female in Shanghai. In Kimchi used dishes Beijing resulted high Kimchi Ramyon 61.5%, Kimchi Kuk 51.3%, and Kimchi Chigae 44.9%, and Shanghai were Kimchi Ramyon 51.2%, Kimchi Kuk 41.3%, and Kimchi Fried Rice 22.4% in order. In evaluation by kinds of Kimchi, the taste resulted high onion juice Kimchi(M=6.55) of the third days, and overall acceptability resulted high onion juice Kimchi(M=6.18) of the third days, similary in Beijing, and Kimchi added in shrimp(M=5.70) of two days, and overall acceptability resulted high Kimchi added in shrimp(M=5.70) of the third days, similary in Shanghai. In Sensory evaluation by used Kimchi, the taste resulted high in the order of Kimchi Fried Rice and Chinese style Kimchi Fried Pork(M=6.27), and overall acceptability resulted Kimchi Fried Udong(M=6.40), Chinese style Kimchi Fried Pork(M=6.27), Kimchi Dumpling(M=6.20) in Beijing, and Kimchi Chige(M=6.70), Kimchi Fried Rice(M=6.67) and Kimchi Pancake(M=6.44), and overall acceptability resulted Kimchi Fried Udong, Kimchi Chige(M=6.50), Kimchi Fried Rice and Kimchi Pancake(M=6.44) in Shanghai.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.723-725
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• 2003

The result of design and Partial fabrication of a 1 MVA single phase high temperature superconducting(HTS) transformer for power distributions are presented in this paper. The HTS windings are wound as double pancake windings which have advantages of uniform distribution of high voltage over the windings. the rated primary and secondary voltages are 22.9 kV and 6.6 kV respectively. Four HTS tapes are wound in parallel for secondary windings considering the rated currents of the transformer. The HTS windings will be cooled down to 65 K by natural convection of sub-cooled liquid nitrogen using a single-staged GM-cryocooler in order to make the stability of the HTS windings better. The iron core is designed as shell type and isolated from the liquid nitrogen by an FRP cryostat which have a room temperature bore. After the complete fabrication of the total HTS transformer system, performance test of the transformer will be carried out.

• Journal of Surface Science and Engineering
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• v.51 no.6
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• pp.415-420
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• 2018

The possibility of an improvement in heat dissipation performance of aluminum alloy heat sink for shipboard LED luminaries through plasma electrolytic oxidation (PEO) was investigated. Four different PEO coatings were produced on aluminum alloy 5052 in silicate based alkaline solution by varying current density ($50{\sim}200mA/cm^2$). On voltage-time response curves, three stages were clearly distinguished at all current densities, namely an initial linear increase, slowdown of increase rate, and steady state(constant voltage). It was found that the increase in current density caused the breakdown voltage to increase. Two different surface morphologies - coralline porous structure and pancake structure - were confirmed by SEM examination. The coralline porous structure was predominant in the coatings produced at lower current densities (50 and $100mA/cm^2$) while under high current densities(150 and $200mA/cm^2$) the pancake structure became dominant. The coating thickness was measured and found to be in a range between about $13{\mu}m$ and $44{\mu}m$, showing increasing thickness with increasing current density. As a result, $100mA/cm^2$ was proposed as an effective process parameter to improve the heat dissipation performance of aluminum alloy heat sink, which could lower the LED operating temperature by about 30%.