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Studies on the Desulfurization of 1,3,4-Oxathiazol-2-one and 1,2,4-Dithiazol-3-one with Trivalent Phosphorus Compounds (1,3,4-옥사티아졸-2-온과 1,2,4-디티아졸-3-온의 3가인 화합물과의 탈황반응에 관한 연구)

  • Dong Young Oh;Chung Ryeol Kim
    • Journal of the Korean Chemical Society
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    • v.27 no.5
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    • pp.368-375
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    • 1983
  • The reactions of various 5-aryl-1,3,4-oxathiazol-2-ones with triethylphosphite resulted in the formation of the corresponding benzonitriles and ethylphosphorothioate by desulfurization reaction in 66∼94% yields. 5-(4-Nitrophenyl)-1,3,4-oxathiazol-2-one was also reacted with trimethylphosphite, triethylphosphine, and triphenylphosphine to give 4-nitrobenzonitrile. But it did not react with triphenylphosphate. The reactions of 5-(4-bromophenyl)-1,2,4-dithiazol-3-one with triphenylphosphine resulted in the formation of 4-bromothiobenzoyl isocyanate and triphenylphosphine thioxide. The thioacyl isocyanate was fragmented into nitrile in ether but was stable in chloroform. This desulfurization reaction observed in each reaction may proceed by the intramolecular rearrangement after insertion of the phosphorus compound into the ring. The stable thioacyl isocyanate in chloroform reacted with imine to give 1,3,5-thiadiazin-4-one via 1,4-cycloaddition reaction.

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Bicycle Wear Survey Based a Study on the Development of the Commute for Bike Wear Textile Design (바이크복 현황조사를 기반으로 한 출.퇴근용 바이크복 텍스타일 디자인 개발에 관한 연구)

  • Lee, Youn-Soon;Eum, Ji-Eun
    • Journal of the Korea Fashion and Costume Design Association
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    • v.14 no.4
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    • pp.179-190
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    • 2012
  • During recent few years, Bike is arising as one of the most important item of sports market. As well as in domestic markets, customers are demanding specific brands only for young aged riders. Therefore, this study researched current bike wears and suggest digital textile printing with sports wear trends which also have safety and visual impact effectiveness, so it can be satisfied as green products and we also try to suggest sports sensitivity of existing cycle wear to city fashion. The purpose of this study is to figure out 20's-30's female biker attitude for bike wear and their purchasing habits and also their preference, digital textile design of city biker wear based on present condition research of riding wear markets and to establish high quality products with occupying high percentage of global markets and making high profits. For this study, bike wear distributors Survey First, foreign companies generally meet evenly sampling the 20s and 30s targeted vendors 10 companies were selected. 'city sporty ware' or 'casual line' dual 'extreme line' from all manufacturers, including, however did not distinguish it from all the vendors. This higher proportion of the recent upsurge in public and non-professional riders, despite the fact that you can see that the lack of 'Extreme line' compared to the 'casual' line of the city sporty ware production. overall seasonal sales in the spring appeared windbreak jacket, leggings and sweat emissions and at the same time built into the fabric dry faster T-shirt and shorts in the summer sales were higher. autumn jacket and produced excellent warm in winter fleece fabric T-shirts, pants, windshield jacket higher sales. showed improvements in design, improved in the order of the highest and perfect for everyday wear for both. As mentioned, we figure out 20's-30's female rider's attitude for riding suit and their purchasing habits and also their preference, so we can develop riding suit design based on their needs and suggest new design patterns.

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Urban energy transition and energy autonomy in Daegu (대구의 도시 에너지 전환과 에너지 자립)

  • Choi, Byung-Doo
    • Journal of the Economic Geographical Society of Korea
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    • v.16 no.4
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    • pp.647-669
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    • 2013
  • Depletion of fossil fuels and sharp rise of international oil price as well as climate worming and frequent environmental disasters have required to strengthen resource(esp. energy) and environmental policy and discourse. And hence highly influential discourses and policies such as the concept of sustainable development and strategy for carbon regulation have been developed and pursued world-widely. But these concept and strategy have seemed to be subsumed in the process of neoliberalism, so as to have little effective results. This leads us to energy transition and energy autonomy or autarky as alternative strategic and normative concepts. Daegu has shown strong interests in urban energy problems relatively earlier than other cities, and developed the so-call 'Solar City' project. But it could not properly tackled with the problems, while tending to meet with the global imperatives. This paper considers urban energy problems and energy policy of Daegu with its significance and limitations, and suggests 4 principles for urban energy transition and autonomy with some concrete alternative measures; that is, the transition from fossil and nuclear energy to renewable energy, the transition from supply-led policy to demand side focusing policy, the transition from central governing energy system to locally distributed one, and the transition from market-dependent management to citizen-participatory energy governance.

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RF Capacitive Coupling Link for 3-D ICs (3-D 집적회로용 RF 커패시티브 결합 링크)

  • Choi, Chan-Ki;Cui, Chenglin;Kim, Seong-Kyun;Kim, Byung-Sung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.24 no.10
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    • pp.964-970
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    • 2013
  • This paper presents a bandpass wireless 3-D chip to chip interface technique. The proposed technique uses direct amplitude modulation of the free running oscillator which especially utilizes the coupling capacitance between two stacked chips as a part of the resonator. Therefore, the oscillator is three dimensionally configured and a simple envelope detector can be used as a receiver without any additional matching circuitry. The proposed link was designed and fabricated using 110 nm CMOS technology and experimental results successfully showed the data transmission at a data rate of 2 Gb/s for the stacked chips with a thickness of 50 ${\mu}m$ consuming 4.32 mW. The sizes of the Tx and Rx chips are 0.045 $mm^2$ and 0.029 $mm^2$, respectively.

The Characteristics of Ti-O Buffer Layered Ta/Ta2O5Capacitors on the Al2O3 substrate (Al2O3 기판위에 형성된 Ti-O 완충층을 가진 Ta/Ta2O5커패시티의 특성)

  • 김현주;송재성;김인성;김상수
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.9
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    • pp.807-811
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    • 2003
  • We investigated the electrical characterisitics of T $a_2$ $O_{5}$ (tantalum pentoxide) film and Ti-O/T $a_2$ $O_{5}$ film deposited on $Al_2$ $O_3$based substrate. Ta (tantalum) electrode and $Al_2$ $O_3$ substrate was used for the purpose of simplifying the manufacturing process in IPD's (integrated passive devices). Dielectric materials (T $a_2$ $O_{5}$ and Ti-O/T $a_2$ $O_{5}$ films) deposited on Ta/Ti/A $l_2$ $O_3$ were annealed at 700 $^{\circ}C$ for 60 sec. in vacuum. The XRD results showed that as-deposited T $a_2$ $O_{5}$ film possessed amorphous structure, which was transformed to crystallines by rapid thermal heat treatment. We compared the lnJ- $E^{{\frac}{1}{2}}$, C-V, C-F of both as-deposited and annealed dielectric thin films deposited on Ta bottom electrode. From this results, we concluded that the leakage current could be reduced by introducing Ti-O buffer layer and conduction mechanisms of T $a_2$ $O_{5}$ and Ti-O/T $a_2$ $O_{5}$ could be interpreted appropriately by Schottky emission effect.

Network City as a New Urban Growth Model: A Review on Its Formation, Spatial Structure, Management, and Growth Potential (새로운 도시성장 모형으로서의 네트워크 도시 -형성과정, 공간구조, 관리 및 성장전망에 대한 연구동향-)

  • Sohn, Jung-Yul
    • Journal of the Korean Geographical Society
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    • v.46 no.2
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    • pp.181-196
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    • 2011
  • The purpose of this study is to explore the network city in detail as a new model for explaining urban growth in the changing economic environment in recent years. For this purpose, starting from Batten's (1995) pioneering work on network city in the mid 1990s to the most recent ones, literature is reviewed and various aspects of network city model are examined including formation process, spatial structure, application to management and urban planning, and growth potential. With this, the study aims at providing comprehensive knowledge necessary for evaluating if the network city model is appropriate in explaining the urban phenomena in the 21st century. The result of the review shows that network city model is the one appropriately explaining the changing urban system associated with the economic globalization and the development of transport and information technology. In addition, more and more European city governments tend to adopt this as the urban planning principle.

Improvement effect of formula containing Vitamin A and Vitamin E on the Strech mark (VitaminA와 VitaminE 함유 제제의 Strech mark 개선효과)

  • Kim, Yang-Ho
    • Journal of the Korean Society of Fashion and Beauty
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    • v.2 no.3 s.3
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    • pp.36-43
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    • 2004
  • This is a research on the effect of formula containing of vitamin A and vitamin E(Frie of oil, Wlter Bouhon GmBH, Germany) on the strech mark. The participants of this study were 20 women at the age of early 20s through middle 20s, who had strech marks that had been over 1 year at the minimum and at less than 5 years at the maximum. Formula containing of vitamin A and vitamin E was applied with typical massage to strech marks for 4 months and twice per day. Improvement resulting from the application was evaluated through observation with the naked eye, questionnaire survey, and the equipment used was DermaScan C Ver3(Cortex Technology, Denmark). The experiment showed that parts cared with formula containing of vitamin A and vitamin E had less strech marks than those control site(treated with jojoba oil).In around 2 months since the use of the formula containing of vitamin A and vitamin E, the tensile of the skin increased and deep wrinkles on the chapped surface became unclear, and in around 4 months the tensile force again decreased and the resilience of the skin increased, and the ultrasonic image showed the decrease of echo pore-zone, which indicates the degree of tissue damage. According to the result of the questionnaire survey, strech marks of less than red strech marks of primary stage were improved more quickly than white strech marks and all participants appeared to experience improvement. The result shows that if this formula is used continuously over 4 months, it reduces strech marks and increase the resilience of the skin. It is considered necessary to continue objective measuring and research concerning strech marks.

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Performance Analysis of Hybrid DS/FH-CDMA over Nakagami Fading Channels with Near-Far Problem (원근문제와 나카가미 페이딩을 고려한 하이브리드 DS/FH-CDMA 방식의 성능 분석)

  • 임태길;강희조
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.10 no.7
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    • pp.1118-1130
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    • 1999
  • In this paper, error performance of DS/FH CDMA system has been analyzed in a radio channel which is characterized by near-far problem and multi-path fading. The DS/FH CDMA system adopts Maximum Ratio Combining(MRC) diversity and BCH(Bose-Chau dhuri-Hocquenghem) coding techniques to enhance system performance. Using the derived error probability equation, the error performance of DS/FH CDMA system has been evaluated and shown in figures to discuss as a function of PN code length(N), hopping rate(q), number of diversity branch(M), coding rate($\gamma$) and bit energy per noise power ratio ${E_b/N_o}$. The results show that DS/FH system is more effective to restrain the affection of near-far problem and multi-path fading than DS system. And there is a substantial enhancement in performance by employing an MRC diversity or BCH coding techniques. Consequently, we expected that proposed system structure is reliable to the voice communication system in near-far problem and multi-path fading channel.

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Part-Of-Speech Tagging using multiple sources of statistical data (이종의 통계정보를 이용한 품사 부착 기법)

  • Cho, Seh-Yeong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.4
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    • pp.501-506
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    • 2008
  • Statistical POS tagging is prone to error, because of the inherent limitations of statistical data, especially single source of data. Therefore it is widely agreed that the possibility of further enhancement lies in exploiting various knowledge sources. However these data sources are bound to be inconsistent to each other. This paper shows the possibility of using maximum entropy model to Korean language POS tagging. We use as the knowledge sources n-gram data and trigger pair data. We show how perplexity measure varies when two knowledge sources are combined using maximum entropy method. The experiment used a trigram model which produced 94.9% accuracy using Hidden Markov Model, and showed increase to 95.6% when combined with trigger pair data using Maximum Entropy method. This clearly shows possibility of further enhancement when various knowledge sources are developed and combined using ME method.

Error Rate Performance of FH/MFSK Signal with Diversity and Coding Technique in the Interference and Fading Environments (간섭과 페이딩 환경하에서 다이버시티와 부호화 기법을 이용하는 FH/MFSK 신호의 오율 특성)

  • 이문승;심수보
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.11
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    • pp.1311-1319
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    • 1992
  • In the partial-band interference and Rayleigh fading environments, the bit error probability equation of FH/MFSK signal has been derived and the error rate has been evaluated. And the results are shown in graphs and discussed. Here, to improve the error rate performance the repeated diversity and the error-correction coding techniques are adopted. The degree of improvement of error rate performance has been found out in diversity and coding techniques respectively. In diversity case, repetition number is taken as a parameter and in coding case, as the error-correction codes Hamming code, BCH code, and convolutional code are introduced. From the obtained results, we have known that the increase of the number of repetition in diversity technique has been brought a little improvement of performance but the coding technique considerable improvement and in particular, convolutional code is very effective. Therefore, coding technique is considered to be better than repeated diversity to cope with Rayleigh fading and partial-band interference.

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