• Title/Summary/Keyword: Auxiliary phase

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The developments of heavy hydrocarbon reformer for SOFC

  • Bae, Jung-Myeon
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2012.05a
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    • pp.58.2-58.2
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    • 2012
  • Heavy hydrocarbon reforming is a core technology for "Dirty energy smart". Heavy hydrocarbons are components of fossil fuels, biomass, coke oven gas and etc. Heavy hydrocarbon reforming converts the fuels into $H_2$-rich syngas. And then $H_2$-rich syngas is used for the production of electricity, synthetic fuels and petrochemicals. Energy can be used efficiently and obtained from various sources by using $H_2$-rich syngas from heavy hydrocarbon reforming. Especially, the key point of "Dirty energy smart" is using "dirty fuel" which is wasted in an inefficient way. New energy conversion laboratory of KAIST has been researched diesel reforming for solid oxide fuel cell (SOFC) as a part of "Dirty energy smart". Diesel is heavy hydrocarbon fuels which has higher carbon number than natural gas, kerosene and gasoline. Diesel reforming has difficulties due to the evaporation of fuels and coke formation. Nevertheless, diesel reforming technology is directly applied to "Dirty fuel" because diesel has the similar chemical properties with "Dirty fuel". On the other hand, SOFC has advantages on high efficiency and wasted heat recovery. Nippon oil Co. of Japan recently commercializes 700We class SOFC system using city gas. Considering the market situation, the development of diesel reformer has a great ripple effect. SOFC system can be applied to auxiliary power unit and distributed power generation. In addition, "Dirty energy smart" can be realized by applying diesel reforming technology to "Dirty fuel". As well as material developments, multidirectional approaches are required to reform heavy hydrocarbon fuels and use $H_2$-rich gas in SOFC. Gd doped ceria (CGO, $Ce_{1-x}Gd_xO_{2-y}$) has been researched for not only electrolyte materials but also catalysts supports. In addition, catalysts infiltrated electrode over porous $La_{0.8}Sr_{0.2}Ga_{0.8}Mg_{0.2}O_3-{\delta}$ and catalyst deposition at three phase boundary are being investigated to improve the performance of SOFC. On the other hand, nozzle for diesel atomization and post-reforming for light-hydrocarbons removal are examples of solving material problems in multidirectional approaches. Likewise, multidirectional approaches are necessary to realize "Dirty energy smart" like reforming "Dirty fuel" for SOFC.

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A Study on Fingerprint-Based Coil Alignment Improvement Technique for Magnetic Resonant Wireless Power Transfer System (핑거프린트 방식의 자기 공진형 무선전력전송 코일 정렬 상태 개선 기법 연구)

  • Kim, Sungjae;Lee, Euibum;Ku, Hyunchul
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.30 no.1
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    • pp.38-44
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    • 2019
  • This paper proposes fingerprint-based positioning methods which can be used in a magnetic resonant wireless power transfer(WPT) system and verifies their performance. A new receiver coil with small orthogonal auxiliary coils is proposed to measure magnetic field signals in three axial directions. The magnitude and phase characteristics of the three-axis electromotive force can be obtained by using the proposed coil. To predict a position with the measured values, we propose a lookup table-based method and linear discriminant analysis-based method. For verification, the proposed methods are applied to predict 75 positions of the 6.78 MHz WPT system, and the performances such as accuracy and computation time are compared.

A Study on the Architectural History and the Process of Transformation of the ILDU Historic House (일두고택의 건축 내력과 변천에 관한 연구)

  • Joung, In-Sang
    • Journal of the Korean Institute of Rural Architecture
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    • v.25 no.4
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    • pp.25-35
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    • 2023
  • According to this study, it is estimated that the ILDU historic house was constructed around the late Goryeo period, approximately in the year 1360, and the founder moved to Hamyang no earlier than 1350. The main house, the inner store-house, the inner gatehouse, and the ancestral shrine, which are situated on elevated ground, were initially constructed around 1360, and substantial expansions and renovations occurred around 1620. The shrine was relocated and reconstructed in its present location and form around 1843. Subsequent to that period, it underwent various architectural changes, including repairs and reconstructions. The sub-main house was originally constructed around 1620 and underwent a reconstruction in 1843. The main storehouse was built in 1930. Also, the man's part of house, located on lower ground, was erected in 1843, while the other sub-main house seems to constructed around 1860. The auxiliary buildings, the main gatehouse and the outer storehouse, were initially constructed around 1360. It is estimated that they were similarly relocated and reconstructed in their current form, along with the construction of the man's part of house in 1843. It has undergone a four-stage transformation process, influenced by various internal and external factors, including the local indigenization of the ILDU families of the same clan, as well as the popularization of Confucian ideology. These four stages include its formative period, growth phase, developmental stage, and maturity. It actively incorporated the contemporary factors of change into its residential architecture. This continuous adaptation is evident in its the space and floor plan, ultimately leading to its present-day architectural legacy.

Antibacterial properties of traditional ceramic glazes containing copper oxide (산화구리를 함유하는 전통 세라믹 유약의 항균특성에 관한 연구)

  • Kim, Ung-Soo;Choi, Jung-Hoon;No, Hyung-Goo;Han, Kyu-Sung;Kim, Jin-Ho;Hwang, Kwang-Taek
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.29 no.6
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    • pp.372-378
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    • 2019
  • Traditional ceramic glazes formulated with copper oxide (CuO) exhibited antibacterial properties on Staphylococcus aureus (Gram Positive) and Escherichia coli (Gram Negative). All the ceramic glazes containing CuO showed antibacterial behavior when fired in reducing atmosphere. However, some of copper glazes presented antibacterial behavior and had no antibacterial properties at all when sintered in an oxidizing atmosphere. To elucidate the antibacterial mechanism, ceramic glazes were studied for phase and microstructure analysis, dissolution behavior and surface zeta potential. Metallic copper was precipitated in the glaze layer when sintered in reducing atmosphere. Less than 0.05 ppm of Cu ion was dissolved from glazes. Ca ion was most dissolved among all the samples. Glaze surface was highly negatively charged when CuO was added over 3 wt.% regardless of the sintering atmosphere. The antibacterial behavior of ceramic glazes seemed to be directly related to the dissolution behavior of cations, but the antibacterial behavior of oxidized specimens was not explained by the dissolution behavior. Surface potential of ceramic glazes appeared to play an auxiliary role in antibacterial properties.

A study of Artificial Intelligence (AI) Speaker's Development Process in Terms of Social Constructivism: Focused on the Products and Periodic Co-revolution Process (인공지능(AI) 스피커에 대한 사회구성 차원의 발달과정 연구: 제품과 시기별 공진화 과정을 중심으로)

  • Cha, Hyeon-ju;Kweon, Sang-hee
    • Journal of Internet Computing and Services
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    • v.22 no.1
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    • pp.109-135
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    • 2021
  • his study classified the development process of artificial intelligence (AI) speakers through analysis of the news text of artificial intelligence (AI) speakers shown in traditional news reports, and identified the characteristics of each product by period. The theoretical background used in the analysis are news frames and topic frames. As analysis methods, topic modeling and semantic network analysis using the LDA method were used. The research method was a content analysis method. From 2014 to 2019, 2710 news related to AI speakers were first collected, and secondly, topic frames were analyzed using Nodexl algorithm. The result of this study is that, first, the trend of topic frames by AI speaker provider type was different according to the characteristics of the four operators (communication service provider, online platform, OS provider, and IT device manufacturer). Specifically, online platform operators (Google, Naver, Amazon, Kakao) appeared as a frame that uses AI speakers as'search or input devices'. On the other hand, telecommunications operators (SKT, KT) showed prominent frames for IPTV, which is the parent company's flagship business, and 'auxiliary device' of the telecommunication business. Furthermore, the frame of "personalization of products and voice service" was remarkable for OS operators (MS, Apple), and the frame for IT device manufacturers (Samsung) was "Internet of Things (IoT) Integrated Intelligence System". The econd, result id that the trend of the topic frame by AI speaker development period (by year) showed a tendency to develop around AI technology in the first phase (2014-2016), and in the second phase (2017-2018), the social relationship between AI technology and users It was related to interaction, and in the third phase (2019), there was a trend of shifting from AI technology-centered to user-centered. As a result of QAP analysis, it was found that news frames by business operator and development period in AI speaker development are socially constituted by determinants of media discourse. The implication of this study was that the evolution of AI speakers was found by the characteristics of the parent company and the process of co-evolution due to interactions between users by business operator and development period. The implications of this study are that the results of this study are important indicators for predicting the future prospects of AI speakers and presenting directions accordingly.

Effect of PVP on the Physical Stability of O/W Emulsion (O/W 유제의 물리적 안정성에 대한 PVP의 영향)

  • Oh, In-Joon;Lee, Mi-Young;Lee, Jeong-Min;Lee, Yong-Bok;Shin, Sang-Chul;Choi, Bo-Guil;Kim, Chong-Kook
    • Journal of Pharmaceutical Investigation
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    • v.27 no.4
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    • pp.287-293
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    • 1997
  • To make a stable o/w emulsion, the effects of egg lecithin as an emulsifier and polyvinylpyrrolidone (PVP) as an auxiliary emulsifier on the physical stability of emulsion were investigated. The oil-in-water emulsion system was manufactured by microfluidizer and evaluated the physical stability. Average particle size and size distribution of emulsion was measured by dynamic light scattering analyzer and interfacial tension was measured. From the interfacial tension tested, critical micelle concentration of the egg lecithin was 0.1 %w/v and optimal concentration for the preparation of emulsion was 1.0 %w/v. The mean particle size was about $0.2\;{\mu}m$ which was suitable for injections. The short-term accelerated stability studies were conducted by centrifugation, freeze-thaw method and shaking of the emulsion samples. The addition of PVP was caused the reduction in the particle size and improved the physical stability of emulsion. These results suggested that a mixed interfacial film comprising the egg lecithin and PVP was formed at the o/w interface and it was effective in preventing phase separation under thermic or mechanical stress. We used antineoplaston A10 (A10) as a model drug which is peptide and amino acid derivative having a action to the living organism against the development of neoplastic growth by a nonimmunological progress. It has a poor solubility in water and there may be a difficulty in formulation of A10. Emulsion formulation study about A10 was performed. Solubility of A10 in emulsion was about five times as high as that in water. From the results of solubility and partition coefficient, almost A10 molecules in o/w emulsion exist in the interface between oil and water.

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A Study on the Utilization and Control Method of Hybrid Switching Tap Based Automatic Voltage Regulator on Smart Grid (스마트그리드의 탭 전환 자동 전압 조정기의 다중 스위칭 제어 방법 및 활용 방안에 관한 연구)

  • Park, Gwang-Yun;Kim, Jung-Ryul;Kim, Byung-Gi
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.12
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    • pp.31-39
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    • 2012
  • In this paper, we propose a microprocessor-based automatic voltage regulator(AVR) to reduce consumers' electric energy consumption and to help controlling peak demanding power. Hybrid Switching Automatic Voltage Regulator (HS-AVR) consist of a toroidal core, several tap control switches, display and command control parts. The coil forms an autotransformer which has a serial main winding and four parallel auxiliary windings. It controls the output voltage by changing the combination of the coils and the switches. Relays are adopted as the link switches of the coils to minimize the loss. To make connecting and disconnecting time accurate, relays of the circuit have parallel TRIACs. A software phase locked loop(PLL) has been used to synchronize the timings of the switches to the voltage waveform. The software PLL informs the input voltage zero-crossing and positive/negative peak timing. The traditional voltage transformers and AVRs have a disadvantage of having a large mandatory capacity to accommodate maximum inrush current to avoid the switch contact damage. But we propose a suitable AVR for every purpose in smart grid with reduced size and increased efficiency.

Time Adverb 'Cengjing (曾經)' and 'Yijing (已經) Tense and Aspect of the Comparative Analysis of the Characteristics of China and South Korea (시간부사 '증경(曾經)', '이경(已經)' 시상(時相) 자질 중한 대조분석)

  • Han, Keung-Shuk
    • Cross-Cultural Studies
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    • v.42
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    • pp.451-474
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    • 2016
  • Analysis of the syntactic structure of the modern Chinese adverbs for time 'Cengjing (曾經)' and 'Yijing (已經)' was performed to examine the tenses and aspects of the terms. The corresponding Korean words were examined and the terms in both languages were compared. The syntactic structures used in China and South Korea were found to be different. We hope the study of the Chinese language will help Korean students. 'Cengjing (曾經)' specific projects with 'aspect' of, 'Past experience aspect', 'Past continuous aspect', 'Past continuous aspect' in the past tense. [ED: unclear, please reword] These correspond to '_었 (았)_', '_었었_' in the Korean language. 'Yijing (已經)' has 'finished phase' of concrete projects, 'Past experience aspect', 'Past continuous aspect', also has a specific project tense, the 'past tense', 'present tense', 'future tense', and so tense. [ED: unclear, please reword] Adjectives can also be modified with a 'change of status'. These correspond to '_었 (았)_', '_고_', '_었었_', '곧' etc. in Korean. 'Cengjing (曾經)' and the dynamic auxiliary 'Guo (過)' were compared to determine whether they have the aspect and tense features. However, 'Guo (過)' can only modify the predicate verb, so it possesses only aspect characteristics. 'Cengjing (曾經)' modifies the range more widely. 'Yijing (已經)' may be modified by the adverb 'Zai (在)' whereas 'Cengjing (曾經)' may not. Additionally, 'Yijing (已經)' can be modified by predicate adjectives and noun predicates, while 'Cengjing (曾經)' cannot.