• Applied Chemistry for Engineering
• /
• v.18 no.4
• /
• pp.356-360
• /
• 2007

Recently, dye sensitized solar cells (DSSCs) composed of nanoporous $TiO_2$, light-sensitive dyes, electrolytes, and counter electrode have been received much attention. Nanostructured particles with higher surface area for the higher adsorption of Ru (II) dye are required to increase the quantity of light absorption. Also, it has been reported that the key factor to achieve high energy conversion efficiency in the photoelectrode of DSSC is the heat treatment of $TiO_2$ paste with acid addition. In this work, we investigated the influence of acid treatment of $TiO_2$ solar cell on the photovoltaic performance of DSSC. The working electrodes fabricated in this work were characterized by X-ray photoelectron spectroscopy (XPS), extended X-ray absorption fine structure (EXAFS), field emission scanning electron microscope (FE-SEM), and atomic force microscope (AFM). In addition, the influence of nanostructured photoelectrode fabricated with the acid-treated paste on the energy conversion efficiency was investigated on the basis of photocurrent-potential curves. It was found that the influence of acid-treated paste on the photovoltaic efficiency was significant.

• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 1999.11a
• /
• pp.149-152
• /
• 1999

최근 들어 시설재배는 토양재배에서 관비재배, 관비재배에서 양액재배방식으로 전환하려는 농가가 급속히 늘고 있어 시대가 변천하면서 더욱 생력적이고 효율적인 농업방식으로 발전하고 있다. 이는 시설의 구조나 형태가 작물생육에 적합한 환경을 제공하기 위하여 지속적으로 개선되어 왔고, 또한 토양재배시 초래되는 연작장해를 회피하기 위한 농가의 요구가 반영된 결과이다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 1999.11a
• /
• pp.145-148
• /
• 1999

최근들어 토양재배에서 관비재배, 관비재배에서 양액재배방식으로 전환하려는 농가가 급속히 늘고 있어 시대가 변천하면서 시설재배방식은 더욱 생력적이고 효율적인 농업방식으로 발전하고 있다. 이는 시설의 구조나 형태가 작물생육에 적합한 환경을 제공하기 위하여 지속적으로 개선되어 왔고, 또한 토양재배시 초래되는 연작장해를 회피하기 위한 농가의 요구가 반영된 결과이다. (중략)

• Journal of the Korea Convergence Society
• /
• v.10 no.3
• /
• pp.211-220
• /
• 2019

This study was to investigate the physiological activities of bioconversion soybean embryo extract and the effects of sleeping pack containing extract on skin. The aglycone isoflavones of the soybean embryo extract bioconversed with pectinase were identified by HPLC. in vitro tests showed that they were non-toxic, anti-inflammatory, anti-melanin and anti-aging activity. After 4 weeks of human body application with the sleeping pack using extract, the skin surface roughness and eye wrinkles were so improved by low stimulation that the sleeping pack containing bioconversion soybean embryo extract has a positive effect on the skin. We confirmed that the bioconversion soybean embryo extract was effective in enhancing the physiological activity and was useful as a cosmetic material of various formulations.

• Journal of the Korean Geographical Society
• /
• v.43 no.5
• /
• pp.681-700
• /
• 2008

In this study, the spatial and temporal patterns of changes in means and extreme events of temperature and precipitation across the Republic of Korea over the last 35 years (1973-2007) are examined. Over the study period, meteorological winter (December-February) mean minimum (maximum) temperature has increased by $+0.54^{\circ}C$/decade ($+0.6^{\circ}C$/decade), while there have been no significant changes in meteorological summer (June-August) mean temperatures. According to analyses of upper or lower $10^{th}$ percentile-based extreme temperature indices, the annual frequency of cool nights (days) has decreased by -9.2 days/decade (-3.3 days/decade), while the annual frequency of warm nights (days) has increased by +4.9 days/decade (+6.8 days/decade). In contrast, the increase rates of summer warm nights (+8.0 days/$^{\circ}C$) and days (+6.6 days/$^{\circ}C$) relative to changes in summer means minimum and maximum temperatures means are greater than the decreasing rates of winter nights (-5.2 days/$^{\circ}C$) and days (-4.3 days/$^{\circ}C$) relative to changes in winter temperatures. These results demonstrate that seasonal and diurnal asymmetric changes in extreme temperature events have occurred. Moreover, annual total precipitation has increased by 85.5 mm/decade particularly in July and August, which led to the shift of a bimodal behavior of summer precipitation into a multi-modal structure. These changes have resulted from the intensification of heavy rainfall events above 40mm in recent decades, and spatially the statistically-significant increases in these heavy rainfall events are observed around the Taebaek mountain region.

• (The) Research of the performance art and culture
• /
• no.42
• /
• pp.291-319
• /
• 2021

In this paper, I looked for the parts where laughter appeared in the Mundoong, Yangban, Yeongno, and Grandfather and Grandmother of Tongyeong Ogwangdae and Dongrae Yaryu, and investigated the meaning of those parts. Laughter in mask play has made him more tolerant of human injustice and foolishness. I softened the critical content and naturally revealed what I thought should be hidden. Through a short and noisy plot, the opposing forces, the inner conflict of the Mundoong, Yangban, Yeongno, and Grandfather and Grandmother were shown in a realistic and realistic way. The worldview that creates the structure of realism is typically skeptical and ironic, and the worldview that creates the comical structure related to laughter aims for the ultimate emergence of a new order based on unity and harmony. Masking is thought to be a work in the stage of moving from the latter to the former. Therefore, it is judged that laughter in mask play served as an important medium for Korean art thought to have a realist view of the world. This is because various expression methods that induce laughter are working to reveal negativity, reveal the illusion of contemporary values, and naturally expose restraint and taboo suppression. In laughter, there is a path that transforms perception by fusing several elements. There was realism at the end of the pathway to new perception.

• Journal of Engineering Education Research
• /
• v.11 no.1
• /
• pp.101-116
• /
• 2008

As industrial society has changed to knowledge-based society, the needs for the intellectual property education in the engineering school is emphasized. Therefore graduate engineering school in USA, Europe, and Japan has strengthened intellectual property education. The curriculum has expanded from intellectual property introduction to business development using patent technology, valuation of intellectual property, intellectual property strategy and management. However, the intellectual property education in engineering school in Korea is in early stage. This study has surveyed the intellectual property education in major engineering school in USA, Europe and Japan, and compared it with the education in Korean engineering school. Finally, some recommendations are provided based on this study.

• 지역과문화
• /
• v.7 no.3
• /
• pp.23-48
• /
• 2020

Hahoebyeolsingut Talnori, which is under permanent performance, has lost its relevance to folklore and rituals of the villagers and has secured the possibility of change depending on the actor's choice. This article seeks to expand the current stuck performance of Hahoe mask play, which has great significance as a play and play for the audience. To this end, We studied the possibility of expanding the performance of Hahoe Talnori by trans-identity of the Choragi. Chorangi character derides yangban, seonbi and monk, who are representatives of the establishment. Those who have a consciousness of potential transformation, those who passively represent the masses, and those who are tacitly authorized by the audience to ridicule the ruling class. The audience feels exhilarated by the super-cool, but at the same time reduces the limits. We transformed Chorangi who is clever but cannot overcome the limits of his status, into a character with a sense of transformation by applying the method of turnning identity and changing identity of the theory of trans-identity. And I applied the method of expansion of the media conversion storytelling theory to create a new Chorangi Madang that conforms to the audience's needs and the spirit of the times. In addition to the performance of Yangban Seonbi Madang(Act of Nobleman and Scholar) which ends with an ambiguous reconciliation, we wanted to complete it in a way that even today's audiences could accept by applying the function of the Hahoebyeolsingut Talnori ambassador and the principle of implementation. And We writed it in a script. This article is meant to be an experimental study that attempted to transform traditional performing arts in the context of new creation of tradition. Preservation and transmission of traditional performing arts are important, but it is necessary to move forward according to the trend and spirit of the times.

• Journal of Energy Engineering
• /
• v.19 no.2
• /
• pp.73-80
• /
• 2010

A solid oxide fuel cells(SOFC) is a clean energy technology which directly converts chemical energy to electric energy. When the SOFC is used in cogeneration then the efficiency can reach higher than 80%. Also, it has flexibility in using various fuels like natural gases and bio gases, so it has an advantage over polymer electrolyte membrane fuel cells in terms of fuel selection. A typical cathode material of the SOFC in conjunction with yttria stabilized zirconia(YSZ) electrolyte is still Sr-doped $LaMnO_3$(LSM). Recently, application of mixed electronic and ionic conducting perovskites such as Sr-doped $LaCoO_3$(LSCo), $LaFeO_3$(LSF), and $LaFe_{0.8}Co_{0.2}O_3$(LSCF) has drawn much attention because these materials exhibit lower electrode impedance than LSM. However, chemical reaction occurs at the manufacturing temperature of the cathode when these materials directly contact with YSZ. In addition, thermal expansion coefficient(TEC) mismatch with YSZ is also a significant issue. It is important, therefore, to develop cathode materials with good chemical stability and matched TEC with the SOFC electrolyte, as well as with high electrochemical activity.

• 한국신재생에너지학회:학술대회논문집
• /
• 2006.06a
• /
• pp.73-76
• /
• 2006

본 연구에서는 독일 율리히 연구소에서 도입된 면적 200mm*200mm의 연료극 지지체 평판형 SOFC 셀 및 금속 분리판 40장을 적층하여 5kW급 SOFC 스택을 제작하고 연속운전을 수행하여 운전특성을 분석했다. 본 연구를 통해 도입된 5kW급 SOFC 스택은 외국에서 시도된 적이 없는 평판형 SOFC스택의 가압운전을 시도해 보는 것으로서, 스택의 임계압력 특성을 확인하고, 이를 바탕으로 가스터빈-연료전지 하이브리드 시스템에서의 SOFC 스택 가압 운전기술을 확보하는 것이다 이러한 목적을 위해 본 연구에서는 상압형 5kW급 SOFC 스택 운전시스템에 대한 구성과 설계, 전반적인 운전 특성평가 (40셀 스택 운전 열 사이클 시험 연료 전환 $(H_2{\rightarrow}pre-reformed\;gas)$, 1200시간 연속운전 등)가 이뤄졌다.