• Title, Summary, Keyword: Unfolding

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Phenological Studies of Deciduous Trees in the Cool Temperate Region of Japan

  • Jun, Kala;Hayashi, Ichiroku
    • Journal of Ecology and Environment
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    • v.31 no.3
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    • pp.193-200
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    • 2008
  • We obtained quantitative information on leaf unfolding and leaf shedding by observing 45 species of cool temperate deciduous trees in an arboretum over 5 growing seasons. These trees were in leaf (the foliage period) for 207 days on average after 1 April; 50% of leaves had been shed by 192 days after 1 April. Duration from the start of leaf unfolding to 50% leaf shedding was 157 days on average. Leaf unfolding began 35 days on average after 1 April. For leaf unfolding to begin, a$ 51^{\circ}C{\cdot}day$ of cumulated daily mean air temperature above $5^{\circ}C$ from 1 January (modified Kira's warmth index) was needed. Fifty-nine days elapsed between initiation and the final stage of leaf unfolding. The period of net photosynthetic assimilation was 157 days. The species with succeeding- type leaf unfolding associated with the anemochore seed type dominated the early stage of succession, while the species with flush-type leaf unfolding tended to dominate the late stage of succession. Few species were found in regions where late frosts occur after the day when the cumulative temperature for leaf unfolding is achieved. Biological characteristics include time of leaf unfolding, which affects the life history of each species, so that each species occupies its own niche in the stand. We conclude that that leaf phenology, such as timing of leaf unfolding and leaf shedding, is one of the components of each species' ecological characteristics.

Decreased entropy of unfolding increases the temperature of maximum stability: Thermodynamic stability of a thioredoxin from the hyperthermophilic archaeon Methanococcus jannaschii

  • Lee, Duck-Yeon;Kim, Kyeong-Ae;Kim, Key-Sun
    • Journal of the Korean Magnetic Resonance Society
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    • v.8 no.1
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    • pp.1-18
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    • 2004
  • A thioredoxin from hyperthermophile, Methanococcus jannashii (MjTRX) was characterized by use of the differential scanning calorimetry to understand the mechanisms of thermodynamic stability. MjTRX has an unfolding transition temperature of 116.5$^{\circ}C$, although the maximum free energy of the unfolding (9.9 Kcal/mol) is similar to that of E. coli thioredoxin (ETRX, 9.0 Kcal/mol). However, the temperature of maximum stability is higher than ETRX by 20$^{\circ}C$, indicating that the unfolding transition temperature increased by shifting the temperature of maximum stability. MjTRX has lower enthalpy and entropy of the unfolding compared to ETRX maintaining a similar free energy of the unfolding. From the structure and the thermodynamic parameters of MjTRX, we showed that the unfolding transition temperature of MjTRX is increased due to the decreased entropy of the unfolding. Decreasing the unfolded state entropy and increasing the folded state entropy can decrease the entropy of the unfolding. In the case of MjTRX, the increased number of proline residues decreased the unfolded state entropy and the increased enthalpy in the folded state increased the folded state entropy.

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JOB-SHOP SCHEDULING ANALYSIS IN FLEXIBLE MANUFACTURING SYSTEM USING UNFOLDING (UNFOLDING을 이용한 유연생산시스템의 JOB-SHOP스케쥴링 분석)

  • 김정원
    • Proceedings of the Korea Society for Simulation Conference
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    • pp.137-141
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    • 1998
  • 본 연구는 TPN unfolding을 이용하여 WIP의 FMS(Flexible Manufacturing System)를 분석하는 방법을 제시한다. PN의 unfolding은 상태폭발이 발생하지 않는 concurrent system의 검증에 사용되는 순서기반방법이다. 본 연구는 일반적으로 발생하는 순환상태스케쥴문제에서 가장 그 작업과정 시간을 최적화함을 위하여 원래의 net을 동일한 비순환 net으로 바꾸어 줄 수 있는 unfolding 개념을 기반으로 한 것이다.

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A SCHEDULING ANALYSIS OF FMS USING TPN UNFOLDING (타임패트리 네트 UNFOLDING을 이용한 FMS의 스케줄링 분석)

  • 이종근
    • 제어로봇시스템학회:학술대회논문집
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    • pp.205-205
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    • 2000
  • In this paper, we are proposed an analysis method of the operation schedule in FMS using Time Petri Nets(TPN) unfolding. TPN's unfolding is one of the analysis methods after changed non-cyclic net from the concurrent net without to expand the state explosion. We are illustrated this proposed to analyze a schedule problem in Ratio-driven FMS modeling.

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A STUDY OF AERODYNAMIC MODELING FOR UNFOLDING WING MOTION ANALYSIS (전개하는 날개의 공력 모델링 연구)

  • Jung, S.Y.;Yoon, S.J.
    • 한국전산유체공학회:학술대회논문집
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    • pp.245-250
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    • 2008
  • For simulation of a wing unfolding motion for the various aerodynamic conditions, equation governing unfolding motion and moments applying to the unfolding wing were modelled. Aerodynamic roll moment consists of the static roll moment and the damping moment, which were obtained through wind tunnel tests and numerical analyses respectively. Panel method was used to compute the roll damping coefficient with twisted wing, whose deflection angle was equivalent to angle of attack due to the deployment motion. Roll damping coefficient is a function of angle of attack, sideslip angle, and deployment angle but not of angular velocity of deployment. Simulation with aerodynamic damping model gave more similar deployment time compared to wing deployment test results.

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A STUDY OF AERODYNAMIC MODELING FOR UNFOLDING WING MOTION ANALYSIS (전개하는 날개의 공력 모델링 연구)

  • Jung, S.Y.;Yoon, S.J.
    • 한국전산유체공학회:학술대회논문집
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    • pp.245-250
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    • 2008
  • For simulation of a wing unfolding motion for the various aerodynamic conditions, equation governing unfolding motion and moments applying to the unfolding wing were modelled. Aerodynamic roll moment consists of the static roll moment and the damping moment, which were obtained through wind tunnel tests and numerical analyses respectively. Panel method was used to compute the roll damping coefficient with twisted wing, whose deflection angle was equivalent to angle of attack due to the deployment motion. Roll damping coefficient is a function of angle of attack, sideslip angle, and deployment angle but not of angular velocity of deployment. Simulation with aerodynamic damping model gave more similar deployment time compared to wing deployment test results.

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Three Binding Sets Analysis of $\alpha$-Lactalbumin by Interaction of Tetradecy Trimethyl Ammonium Bromude

  • M.R.Housainfokht
    • Bulletin of the Korean Chemical Society
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    • v.22 no.2
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    • pp.145-148
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    • 2001
  • The interaction between tetradecyl trimethyl ammonium bromide (TTAB) with bovine ${\alpha}-lactalbumin$ has been investigated at pH = 9 and at $37^{\circ}C$ by isothermal titration calorimetry, equilibrium dialysis and UV-Vis spectrophotometry methods. The binding data from unusual Scatchard plot have been analyzed in terms of the Hill equation for three sets of binding sites. The calorimetric data show that TTAB interacts endothermically with ${\alpha}-lactalbumin$ and causes protein unfolding below 2 mM concentration of TTAB, which is confirmed by spectrophotometric data. The unfolding of the protein would be mainly due to occupation of the second set of binding sites.

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A Scheduling Analysis of FMS Using TPM Unfolding (타임 패트리넷 Unfolding을 이용한 FMS의 스케쥴링 분석)

  • Lee, Jong-Geun
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.4
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    • pp.344-350
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    • 2001
  • In this paper, we are focused on the analysis of acyclic schedule for the determination of the opti-mal cycle time and minimization of work in process. Especially, this paper deals with the product ratio-driven cyclic scheduling problem in FMS with different products and ratio using the TPN(Time Petri Nets)un-folding.

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