• 제목/요약/키워드: TOUGH2

검색결과 192건 처리시간 0.03초

Novel Sulfonated Poly(arylene ether ketone) Containing Benzoxazole Membranes for Proton Exchange Membrane Fuel Cell

  • Li Jin-Huan;Lee Chang-Hyun;Park Ho-Bum;Lee Young-Moo
    • Macromolecular Research
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    • 제14권4호
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    • pp.438-442
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    • 2006
  • Novel sulfonated poly(aryl ether ketones) containing benzoxazole were directly synthesized by aromatic nucleophilic polycondensation using various ratios of 2,2'-bi[2-( 4-flurophenyl)benzoxazol-6-yl]hexafluoropropane to sodium 5,5'-carbonylbis(2-fluorobenzenesulfonate). The copolymers were soluble in polar aprotic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, and N,N-dimethylformamide at a relatively high solid composition (>15 wt%) and formed tough, flexible and transparent membranes. The membranes exhibited a degradation temperature of above $290^{\circ}C$. The exact dissolution times of these membranes at $80^{\circ}C$ in Fenton's reagent (3 wt% $H_2O_2$ containing 2 ppm $FeSO_4$) were undetectable, confirming their excellent chemical stability in fuel cell application. The membranes showed a moderate increase in water uptake with respect to increasing temperature. The proton conductivities of the membranes were dependent on the composition and ranged from $1.10{\times}10^{-2}$ to $5.50{\times}10^{-2}Scm^{-1}$ at $80^{\circ}C$ and 95% relative humidity (RH). At $120^{\circ}C$ without externally humidified conditions, the conductivities increased above $10^{-2}Scm^{-1}$ with respect to increasing benzoxazole content, which suggested that the benzoxazole moieties contributed to the proton conduction.

여자대학생의 시어머니에 대한 고정관념 (Stereotypes of the Mother-in-law Held by Female Students)

  • 이영숙;박경란
    • 가정과삶의질연구
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    • 제24권1호
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    • pp.1-9
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    • 2006
  • The purpose of this research is to identify stereotypes toward the mother-in-law held by female students. Stereotypes toward the mother-in-law were examined at two levels: to assess female students' beliefs about the traits of mother-in-law and to categorize the traits into stereotypes. The main results of this study were as follows: 1) Students reported 91 traits associated with the mother-in-law. 2) Hierarchical cluster analysis of the trait groupings revealed two high-level clusters: a cluster of 42 positive traits and a cluster of 49 negative traits. Within the positive and negative clusters, 14 middle-level categories, 6 positive categories(tough, leisurely, traditional image of prudent elders, image of the eldest in the family, intimate, tolerant), and 8 negative categories(dominant, self-assertive, cold, discriminating, fearful, mean, sadistic, authoritative, nervous) were identified. This results suggested that female students believed negative stereotypes are more typical than positive ones.

Set-top box용 an 8-bit 40MS/s Folding A/D Converter의 설계 (An 8-bit 40 Ms/s Folding A/D Converter for Set-top box)

  • 장진혁;이주상;유상대
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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    • pp.626-628
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    • 2004
  • This paper describes an 8-bit CMOS folding A/D converter for set-top box. Modular low-power, high-speed CMOS A/D converter for embedded systems aims at design techniques for low-power, high-speed A/D converter processed by the standard CMOS technology. The time-interleaved A/D converter or flash A/D converter are not suitable for the low-power applications. The two-step or multi-step flash A/D converters need a high-speed SHA, which represents a tough task in high-speed analog circuit design. On the other hand, the folding A/D converter is suitable for the low-power, high-speed applications(Embedded system). The simulation results illustrate a conversion rate of 40MSamples/s and a Power dissipation of 80mW(only analog block) at 2.5V supply voltage.

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가교가능한 유기화합물을 이용한 알루미나의 분산과 성형 (Dispersion and Forming of Alumina Powders via Crosslinkable Organic Molecules)

  • 김봉호;신평우;백운규;정연길;최성철;박철원
    • 한국세라믹학회지
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    • 제32권2호
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    • pp.217-226
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    • 1995
  • Alumina powders were dispersed using crosslinkable organic molecules by electrosteric stabilization and then consolidated by crosslinking of organic molecules. The effect of processing variables such as the physicochemical properties of both solvent media and organic molecules, the proportions of mixed organic media, etc. were studied. FT-IR was used todeduce the mechanism of organic molecules adsorption on the alumina particle surfaces. The adsorption characteristics and the electrokinetic behavior of alumina suspensions were correlated with the stability of particle in alumina suspension using rheological measurements. The green body of alumina consolidated by the chemical crosslinking of the adsorbed organic molecules after the alumina suspension had been stabilized was tough enough for green machining and the sintered alumina fabricated by this proposed process also showed a high bending strength and a homogeneous microstructure.

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한국 고유음료류 개발에 관한 연구중 갈수에 관한 연구 (A study on the development of Korean Indigenous beverages in a research on GAL-Soo)

  • 오승희
    • 기술사
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    • 제15권1호
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    • pp.14-23
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    • 1982
  • 1) The characteristic of the recipe for GAL-SOO is to make odorous, pharmaceutical cereal into plaster by honey-mixed boiling so as to be drunken whenever it needed. But the cereal which included sugar was boiled without adding sugar. 2) The part of cereal which was used mostly in making GAL-SOO was seeds of cereals. 3) The history of GAL-SOO was derived from GU GA PIL YONG, a document of WON dynasty of GHINA, but it was developped according to our taste in this county. 4) The pharmaceutical action of GAL-SOO was mainly to strengthen stomach, digestion and appeasing thirst. 5) GAL-SOO tastes so sour and sweet that it was splendid to drink especially in summer as a beverage. 6) The Value of developping GAL-SOO as a beverage is highly approved because of its expediency of recipe and tough endurance storing under ordinary temperature.

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식물의 암종유발에 관한 연구 1 (제 1 ) Agrobacterium tumefaciens 의 에 관하여 (Studies of Plant Tumor Induction (Pat 1) Experiments on the Inoculation of Agrobacterium tumefaciens in out Field)

  • 이민재;홍순우;최영길
    • 미생물학회지
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    • 제4권2호
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    • pp.1-4
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    • 1966
  • As a part of studies of plant tumor induction, this experiment was prepared for the purpose of studying the ability of tumor induction and the tendency of tumor initiation in some Korean plants using the various Agrobacterium tumefaciens strains. Results obtained from this experiment are as follows. The virulences of five strains used in this experiment were gradually decreased in order of strain A6Kl, B6, 11BV7, T37 and 11 BNV6. Especially strain T37 which is known to the host limited strain showed virulent effect to the most of plants given for the materials as well as strain A6Kl, B 6 and 11BV7. Concerning the grade of tumor development, in plants which has tough stem, for example, Glycine max Meer, tumor induction was not well developed after the inoculation of all strains. Particullary in Ricinus communes Linne all strains showed virulent effect but tumor tissues were declined in relation to the development of lignification. It was also confirmed that the induction of tumor tissues on plants is to delay according to the increase of the age of host plants.

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학교스포츠클럽에 대한 중학교 체육교사의 인식 (Middle School Physical Education Teachers' Perceptions of the School Sports Club)

  • 장한기;최수석
    • 수산해양교육연구
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    • 제23권2호
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    • pp.333-349
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    • 2011
  • The purpose of this study was to examine middle school physical education teachers' perceptions of the School Sports Club, Questionnaires were sent to the all 547 middle school physical education teachers in the Busan Metropolitan City, 326 (59.6%) were returned and 322 (58.9%) were analyzed. The results of the study were as follows: Firstly, there were school sports clubs of 24 kinds of sports at middle schools, but overly concentrated in soccer, basketball and badminton. Secondly, physical education teachers responded positively to the importance of school sports club. Thirdly, They thought that school sports club activities had an effect on both the physical and socio-cultural improvement of students. Fourthly, among tough barriers were time restraint, school parents' unfriendly sentiments toward the activities, and financial difficulties. Fifthly, to have better school sports clubs, reducing the barriers is pivotal.

Preparation and Chain-extension of P(LLA-b-TMC-b-LLA) Triblock Copolymers and Their Elastomeric Properties

  • Kim, Ji-Heung;Lee, Ju-Hee
    • Macromolecular Research
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    • 제10권2호
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    • pp.54-59
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    • 2002
  • ABA triblock copolymers of L-lactide and trimethylene carbonate with several different compositions were prepared by sequential ring-opening polymerization in the presence of diethylene glycol. Also chain-extension reactions of the resulting copolymers were carried out using hexamethylene diisocyanate to produce relatively high molecular weight polymers, which could be cast into elastomeric tough films. The polymers with certain L-lactide contents were partially crystalline, exhibiting two-phase morphology. The polymer films showed reversible elastic behavior under tensile tension, providing a novel thermoplastic elastomer possessing desirable properties such as biodegradability and good mechanical properties.

Lowest-Cost Highest-Yield Superior Performance MVA LCDs by Amplified Intrinsic Fringe Field

  • Ong, Hiap L.;Liang, Justin;Guo, Jia Haw;Chen, I Hao;Wu, Chang Lin;Lan, Wei-Chou;Lin, Tung-Liang
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.1645-1648
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    • 2008
  • We successfully fabricated lowest-cost superior perform ance MVA LCDs with highest-yield, high transmission, high contrast-ratio, and wide viewing angle. Using the amplified intrinsic fringe field (AIFF) controlled MVA invented by Ong, we eliminated all protrusions and ITO slit geometries. We further achieved: (1) faster gray-gray response times without the over-drive technology, (2) faster tough mura, and (3) lower flicker and cross-talk in the row inversion driving schemes.

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전자무역시대 농산물 수출물류 활성화 방안 및 과제 (A Scheme of the Agriculture Export Logistics Improvement in E-Trade Era)

  • 박현희
    • 통상정보연구
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    • 제11권2호
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    • pp.49-66
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    • 2009
  • The DDA negotiations, in 9th multilateral trade round, has focused on nine sectors including agriculture, non-agricultural market access, and service. After August 2004, member countries have intensified negotiations in order to reduce gaps between countries perspective. So most attention of members countries has been focused on agricultural trade and non-agricultural market access. Agricultural negotiation confront tough challenges because of different positions among members countries, and are not expected to reach perfect forms of modalities. Nevertheless based on the fact that many countries nearly reached agreement on some core. Under this circumstance, Korea has to prepare more practical strategics and more effective individual commitments to minimized the agricultural market opening. The other way, some Korean agricultural products will be exported by the DDA negotiation. Recently the understanding of Third-Party Logistics and Logistics Outsourcing are receiving increased attention as means of becoming competitive in agricultural products export improvement. So this paper presents a in-depth analysis for third-party logistics and its implications for Korea agricultural product export system improvement in E-trade Era.

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