• Title/Summary/Keyword: Pair

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Rare-Mating and Protoplast Fusion for the Improvement of Ethanol Producibility and Cell-Viability of Yeast (효모의 에탄올 생산능 및 세포 생존능의 증진을 위한 Rare-mating과 원형질체 융합)

  • Kang, Tae-Young;Kim, Keun
    • Korean Journal of Microbiology
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    • v.37 no.4
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    • pp.312-316
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    • 2001
  • To improve the ethanol fermentability, four Saccharomyces yeast strains with efficient ethanol fermentability were subjected to rare-mating and protoplast fusion. Using these 4 strains, 5 different combinations of mating-pair or fusion-pair were constructed and their hybrids or fusants were obtained. From the statistical analysis of the results of the ethanol fermentation by the hybrids of the different mating-pair or fusion-pair, no difference was found in ethanol production, but [S. kluveri $khl{\times}S$ cerevisiae cp3] pair was shown to be the best combination which can produce high cell-viability. In fact, the clone No. 3 of the [S. kluveri $khl{\times}S$ cerevisiae cp3] pair was selected as the best strain which produced ethanol of 10.11% (w/v) or 12.81% (v/v) from 25% (w/v) glucose at $33^{\circ}C$ for 3 days with the residual sugar of 3.53% (w/v), viability of 62.65%, fermentation efficiency of 92.2%.

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POSTNIKOV SECTIONS AND GROUPS OF SELF PAIR HOMOTOPY EQUIVALENCES

  • Lee, Kee-Young
    • Bulletin of the Korean Mathematical Society
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    • v.41 no.3
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    • pp.393-401
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    • 2004
  • In this paper, we apply the concept of the group \ulcorner(X,A) of self pair homotopy equivalences of a CW-pair (X, A) to the Postnikov system. By using a short exact sequence related to the group of self pair homotopy equivalences, we obtain the following result: for any Postnikov section X$\sub$n/ of a CW-complex X, the group \ulcorner(X$\sub$n/, A) of self pair homotopy equivalences on the pair (X$\sub$n/, X) is isomorphic to the group \ulcorner(X) of self homotopy equivalences on X. As a corollary, we have, \ulcorner(K($\pi$, n), M($\pi$, n)) ≡ \ulcorner(M($\pi$, n)) for each n$\pi$1, where K($\pi$,n) is an Eilenberg-Mclane space and M($\pi$,n) is a Moore space.

Active Vibration Control of a Beam using Direct Velocity Feedback (직접속도 피드백을 이용한 보의 능동진동제어)

  • 이영섭
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.05a
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    • pp.587-592
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    • 2004
  • Direct velocity feedback (DVFB) control is known that it offers an unconditional stability with very high performance when the control strategy is applied at a point collocated sensor and actuator pair, because the sensor-actuator pair has strictly positive real (SPR) property. In this paper, two types of collocated sensor-actuator pairs are considered for practical active vibration control of a structure. They are a point collocated sensor-actuator pair and a point sensor-distributed actuator pair. Both pairs with DVFB sho robust stability and performance. It is noted that the collocated point sensor-actuator ultimately acts as a 'skyhook' damper, but the point sensor-distributed actuator pair with DVFB acts as a 'skyhook' rotational dmaper pair.ational dmaper pair.

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Analysis of Thermodynamic Design Data of Double-Effect Absorption System for Heating using LiCl-water for Evaporator Heating Source of Solar Energy (흡수식 2중효용 시스템의 증발기 열원으로 태양열을 이용하는 LiCl 수용액 난방시스템 해석)

  • Won, Seung-Ho
    • Journal of the Korean Solar Energy Society
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    • v.24 no.3
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    • pp.39-46
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    • 2004
  • In this paper, thermodynamic design data for heating of double-effect absorption system using LiCl-water for evaporator heating source of sofar energy are investigated for the water-LiCl pair and a comparative study of the water-LiCl pair with the water-LiBr pair is given used for the computer simulation. The computer simulation is based on mass, material and heat balance equations for each part of the system. Coefficients of performance and flow ratios for effects of different operating temperatures are investigated. It is found that the heating COP is higher for the water -LiCl pair than for the water-LiBr pair, and FR is lower for the water-LiCl pair than for the water LiBr pair.

Collocation of Sensor and Actuator for Active Control of Sound and Vibration (능동음향진동제어를 위한 센서와 액추에이터의 동위치화 연구)

  • 이영섭
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.14 no.3
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    • pp.253-263
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    • 2004
  • The problem considered in this paper is about the collocation of sensor and actuator for the active control of sound and vibration. It is well-known that a point collocated sensor-actuator pair offers an unconditional stability with very high performance when it is used with a direct velocity feedback (DVFB) control, because the pair has strictly positive real (SPR) property. In order to utilize this SPR characteristics, a matched piezoelectric sensor and actuator pair is considered. but this pair suffers from the in-plane motion coupling problem with the out-of-plane motion due to the piezo sensor and actuator interaction. This coupling phnomenon limits the stability and performance of the matched pair with DVFBcontrol. As a new alternative, a point sensor and distributed piezoelectric actuator pair is also considered, which provides SPR property in all frequency range when the pair is implemented on a clamped-clapmed beam. The use of this sensor-actuator pair is highly expected for the applications to more practical active control of sound and vibration systems with the DVFB control strategy.

Fabrication of Pair-Photonic Crystal Arrays using Multiple-Exposure Nanosphere Lithography (다중노광 나노구 리소그라피를 이용한 쌍-광자결정 어레이 제작)

  • Yeo, Jong-Bin;Han, Gwang-Min;Lee, Hyun-Yong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.23 no.3
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    • pp.245-249
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    • 2010
  • Two dimensional(2D) pair-photonic crystals (pair-PCs) have been fabricated by a multiple-exposure nanosphere lithography (MENSL) method using the self-assembled nanospheres as lens-mask patterns and the collimated laser beam as a multiple-exposing source. The arrays of the 2D pair-PCs exhibited variable lattice structures and shape the control of rotating angle (${\Theta}$), tilting angle (${\gamma}$) and the exposure conditions. In addition, the base period or filling factor of pair-PCs as well as their shapes could be changed by experimental conditions and nanosphere size. A 1.18-${\mu}m$-thick resist was spincoated on Si substrate and the multiple exposure was carried out at change of ${\gamma}$ and ${\Theta}$. Images of prepared 2D pair-PCs were observed by SEM. We believe that the MENSL method is a suitable useful tool to realize the pair-periodic arrays of large area.

A Study on Poly-pulse Pair Estimation Method for Reduction of Bias Errors in a Weather Radar (기상레이다에서의 편향오차 감소를 위한 다중 펄스페어 추정기법에 관한 연구)

  • 이종길
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.12B
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    • pp.2292-2297
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    • 1999
  • Some observed weather spectra show that nearly 25% of weather spectra are seriously skewed and can not be considered to be symmetric. However, the conventional pulse pair method was derived and has been evaluated under the assumption that the weather spectrum is symmetric and narrow. This means that the conventional pulse pair method may need reevaluation. Therefore, this paper analyzed the bias errors of pulse pair estimates in the skewed spectra. The bias errors of pulse pair mean estimates are more serious comparing with the pulse pair width estimates. In this paper, the poly-pulse pair method is suggested to reduce these bias errors of mean estimates. It was shown that the mean bias errors can be reduced remarkably using the newly suggested poly-pulse pair method.

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Design and Implementation of Distributed Pair Programming System based on IDE (IDE 기반의 분산 페어 프로그래밍 시스템의 설계 및 구현)

  • Park, Ji-Hoon;Lee, Kyung-Hwan
    • The KIPS Transactions:PartD
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    • v.11D no.6
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    • pp.1301-1310
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    • 2004
  • In distributed office, the pairs can program together using a distributed pair programming system. Many CSCW tools featuring remote screen sharing function have insufficient usability, accessibility to introduce many developers to distributed pair programming. In this paper, we suggest a distributed pair programming system based on IDE, which many developers will accept and use easily. We have do#eloped a user scenario and GUI of the system, making distributed pair programming easier and designed with high extensibility by adapting design patterns and implemented in Java language. Our findings will be of significant help to developers dealing with implementation of distributed pair programming function into some commercial IDE.

Consideration of Human Factor of Wheelchair and Crutch for the Posteriority Handicapped (후천성 장애인을 위한 휠체어와 목발의 인간공학적 고찰)

  • 구본언;박근상
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.23 no.57
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    • pp.77-85
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    • 2000
  • The purpose of this study is to analyze problems of KS measurement of the wheelchair and a pair of crutches and to propose proper measurements of the wheelchair and a pair of crutches for the posteriori handicapped. Research method is as following ; First, it is compared that Anthropometry of Korean and Japanese adults relevance with design measurement of the wheelchair and a pair of crutches. Second, we compared measurements of KS wheelchairs with measurements of the wheelchair manufactured by the T aids company and the D aids company, and then compared and analyzed differences of measurements about each part of the wheelchair. Third, we compared measurements of a pair of crutches of an fixed and an elastic type with anthropometry and analysis. The result, measurements of KS wheelchair and KS a pair of crutches shows unsuitable to Korean adults. It may cause handicapped. We proposed measurements of the aids(the wheelchair and a pair of crutches) proper to the handicapped of Korean adults with improvement of these problems.

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Oscillation of Critical Current by Gate Voltage in Cooper Pair Transistor (Cooper pair transistor에서 gate voltage에 의한 임계전류의 진동)

  • Song, W.;Chong, Y.;Kim, N.
    • Progress in Superconductivity
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    • v.11 no.2
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    • pp.158-161
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    • 2010
  • We measured the critical current of a Cooper pair transistor consisting of two Josephson junctions and a gate electrode. The Cooper pair transistors were fabricated by using electron-beam lithography and double-angle evaporation technique. The Gate voltage dependence of critical current was measured by observing voltage jumps at various gate voltages while sweeping bias current. The observed oscillation was 2e-periodic, which shows the Cooper pair transistor had low level of quasiparticle poisoning.