• Journal of the Korean Society of Costume
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• v.28
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• pp.47-64
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• 1996

This paper is a study on the expression of Clothing and Textiles recorded in $\ulcorner Makuranosorsi(枕草子) \lrcorner$ This book was written by a Japanese servant in the Royal Court about the year 10000. In this book many kinds of clothing ornament color and materials were mentioned. The discoveries of this paper were as follows. 1. There were 85 different kinds of name In detail there were 46 Clothing and Accessories 32 Clors 11 Materials Patterns the method of Dyeing. 2. All the Clothing and Textiles in Makur-anosorsi were reflections of the reality of that times. 3. From ancient times japanse Costume was much influenced by Korea. but around the 7th century the influence increased. 4. Almost all clothing and Accessories used in Japan in the 10th century had been pre-viosly used in neighboring countries Korea and China But after they were imported to japan some of them were changed to japans hybrids especially in name and shape. 5. In Japan Clothing Colors were used in various ways sometimes colors coordinated by over lapping dress and othertimes the colors were weaved together Namely the width and length of these colorful fibres are also signifi-cant meaning. This meas that the Japanese was much more interested in color than other countries and this also proves Clothing Colors were very developed in japan by the 10th cen-tury. 6. The Materials discovered in this book were almost all silk This is the reason why $\ulcorner Makuranosorsi \lrcorner$ was the expression of the Royal Court.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.415-417
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• 2009

A low temperature decal (LTD) transfer method is tried to fabricated hydrocarbon (HC) membrane based MEA. Sandwiched structures of outer ionomer/catalyst/carbon coating/substrate, which had been developed for Nafion membrane, are used for transfer of catalyst to the HC membrane. Performances of the HC MEA before and after 500hr continuous operation are compared and it is found that a severe delamination occurs at the interface between the HC membrane and the catalyst layer, which is the main reason of the low performance and its degradation. The delamination is due probably to the different nature of HC membrane to the Nafion ionomer. A substitutional method, therefore, is suggested to overcome this. In such a way, the outer ionomer process is removed and the low transfer rate of catalyst by skipping the ionomer process is compensated with optimization of other process variables such as transfer time or temperature. The resulting performance is superior to the original LTD method, which can be explained in terms of low resistive components both in ohmic and kinetic.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.1
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• pp.98-103
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• 2011

The System of Rice Intensification (SRI) is a new concept of increasing the yield of rice produced in farming. Therefore, we investigated the impacts of planting density on nutrient uptake as affected by SRI under no-till cropping system. The field was prepared as a randomized complete block design with three treatments: $10{\times}10$ cm, $20{\times}20$ cm and $30{\times}30$ cm planting densities. The root dry mass was significantly increased in the wider planting densities (p<0.05%). The highest grain yield was obtained in $20{\times}20$ cm planting density plot (p<0.05%) due to higher plant density per unit area and spikelets number per panicle. The total uptake amounts by rice plant were significantly higher in $20{\times}$20 cm planting density plot as 94.8 kg $ha^{-1}$ for T-N and 29.9 kg $ha^{-1}$ for P than other planting densities plots, but K and Mg uptake were significantly higher in $10{\times}10$ cm planting density plot (p<0.05%). In this study, our findings suggest that SRI should be considered as a new practice for the rice productivity.

• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.3
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• pp.262-272
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• 2015

An integrated two-in-one transformer applicable to PSUs for a 120 W LED TV is proposed. This transformer comprises a PFC inductor and an LLC transformer placed and integrated on an E-I-E type magnetic core. Performance is evaluated by observing the coupling coefficients of the proposed two-in-one transformer under various air gap topologies. Among the topologies studied, an integrated transformer with centered air gap shows stable operational characteristics with a minimized mutual coupling (interference). Furthermore, applicability of the proposed integrated transformer to PSUs for a 120 W LED TV is studied from the viewpoint of integrating different magnetic components into one core, resulting to low weight, low cost, and high power density.

• Journal of the Korean Electrochemical Society
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• v.10 no.2
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• pp.104-109
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• 2007

Single fuel cell was fabricated with a MEA (membrane electrode assembly) that had a $4cm^2$ active area and with silicon bipolar plates those were introduced to miniaturize the fuel cell by replacing heavy weight graphite plates. Optimum humidification condition for the single cell was selected based on performance results obtained varying humidifier temperature at a fixed feed rate of hydrogen and oxygen. Furthermore, to study the effect of humidification condition on the performance of a fuel cell stack, the fuel cell stack consisting of two MEAs and silicon bipolar plates was studied, then problems and characteristics of silicon-based fuel cell stack were examined.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.221-223
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• 2007

고분자전해질연료전지의 효율과 수명은 고분자 전해질 막과 밀접하게 관련되어있다. 연료전지 상용화를 위해 내구성과 안정성은 반드시 확보되어야 한다. 본 연구에서는 고분자전해질연료전지용 막전극접합체에 대해서 제작과정, 체결과정 및 운전 중에 발생할 수 있는 물리적 손상이 연료전지에 미치는 영향을 알아보고자 하였다. 실제 고분자전해질연료전지 조건에서 구멍이 생기는 경우를 모사하기 위해 막전극접합체에 다양한 크기 및 형상의 물리적 손상을 형성시켰다. 또한 여러 위치에서의 손상도 비교하였다. 손상시킨 막전극접합체에 대해 단위전지 성능평가와 순환전압전류 실험을 비교 분석하였다. 막전극접합체의 결함이 커질수록 수소기체투과도는 증가하고, OCV와 성능은 감소하였다. 또한 성능과 수소기체투과도는 서로 관련이 있음을 알 수 있었다.

• Journal of Hydrogen and New Energy
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• v.26 no.4
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• pp.318-323
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• 2015

For commercialization of fuel cell electric vehicles, one of the key objectives is to improve durability of MEA and electrocatalysts. Regarding electrocatalysts, the major issue is to reduce carbon corrosion and dissolution of Pt caused by harsh conditions, for example, SU/SD (Start-up/Shut-down). In this research, OER (Oxygen Evolution Reaction) catalyst has been developed improvement of durability. A modified polyol process is developed by controlling the pH of the solvent to synthesize the PtIr nanocatalysts on carbon supports. Each performance of the MEAs applying PtIr and Pt are equivalent because PtIrnanocatalysts have both ORR and OER activity. Breadboard test for catalyst durability in harsh conditions and high potentialsis found that the MEA applying PtIrnanocatalysts durability is improved more than the MEA applying Pt nanocatalysts.

• Journal of Hydrogen and New Energy
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• v.23 no.2
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• pp.125-133
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• 2012

Nafion ionomer located in electrode helps to increase the platinum utilization and proton conductivity. To achieve higher performance in PEMFCs, it is important an optimum Nafion content in the electrode. As the platinum loading and fabricated method depend on the optimum Nafion content. In this study, we have examined the interrelationship between platinum loading and Nafion content fabricated by decal transfer method. For electrodes with 0.25 and 0.4 mg/$cm^2$ Pt loading, best performance was obtained at 25 wt.% Nafion ionomer loading. It is also found that MEA with 0.25 mg/$cm^2$ Pt, the optimum Nafion content appears differently at low and high current density.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.87.1-87.1
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• 2011

For commercial applications, MEA development must be optimized in order to achieve high performance and low cost. There are many factors that affect the performance of MEA. Especially, the optimization of the method for preparing catalyst layer has great effect on the performance of MEA. Various methods have been used to prepare the catalyst layer of MEA. Among them, spraying method has a merit in that catalysis lay can be prepared with very flexible changes in catalyst layer as well as in the solvent composition of catalyst ink. In addition, in order to reduce the time required for manufacturing catalyst layer, an effort has been made to change the nozzle size and injection pressure of spray system. Further, the operation condition of spray system was changed in various ways in an effort to prepare optimum catalyst layer of MEA. Having optimized the operation condition of spraying system, comprehensive and diverse experiments were carried out concerning various factors that affect the performance of MEA. The present research report describes the results of more sub-categorized and more detailed experiments about the important factors (Nafion$^{(R)}$ ionomer, Relative humidity) which have been shown in previous experiments to exert greater effect on the performance of MEA.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1255-1257
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• 1997

In order to obtain key technologies for a kW class internal humidifying proton-exchange-membrane fuel cell (PEMFC) a single cell with a large electrode area has been designed and manufactured and the performance of large area membrane/electrode assemblies (MEAs) has been evaluated by using the single cell. A small area MEA made of commercial E-TEK electrode and Nafion 117 membrane showed a performance of 0.7V, $300mA/cm^2$ whereas large area MEA made of catalyst layer on carbon support and Nafion 117 showed a lower performance. To improve the performance of large MEA direct coating of catalyst was carried out on the membrane using a screen printer.