• Title/Summary/Keyword: LTR

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Identification and Characterization of New Copia-like Retrotransposon Osr1 in Rice

  • Lee, Yong-Hwan;Jwa, Nam-Soo;Park, Sook-Young;Park, Chan-Ho;Han, Seong-Sook
    • The Plant Pathology Journal
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    • v.19 no.1
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    • pp.57-63
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    • 2003
  • An insertion sequence identified as a solo long terminal repeat (LTR) of a new rice copia-like retrotransposon was detected in the ORE of the Pi-b gene from the rice cv. Nipponbare, and was designated as Osr1. Osr1 consists of a 6386 bp nucleotide sequence including 965 bp LTRs on both ends with an 82% nucleotide sequence identity to the wheat Tarl retrotransposon on reverse transcriptase. Nucleotide divergence was noted among the individual LTRs, as well as the coding region of Osr1. Various restriction fragment length polymorphism (RFLP) of LTR were detected in indica cultivars, whereas, only a few could be detected in the japonica cultivars. The population of Osr1 is lower in the wild-type rice compared with that in the domesticated cultivars. The insertion of LTR sequence in the h-b gene in the susceptible cultivar suggested that retro-tyansposon-mediated insertional mutation might play an important role in the resistance breakdown, as well as in the evolution of resistance genes in rice.

The LQG/LTR Dynamic Digital Control System Design for the Nuclear Steam Generator Water Level (증기발생기 디지탈 수위조절 시스템의 LQG / LTR 동적 제어설계)

  • Lee, Yoon-Joon
    • Nuclear Engineering and Technology
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    • v.27 no.5
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    • pp.730-742
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    • 1995
  • The steam generator feedwater and level control system is designed by two steps of the feedwater control design and the feedback loop controller design. The feedwater sen system is designed by the optimal LQR/LQG approach and then is modified by the LTR method to recover the robustness. The plant characteristics are subject to change with the power variation and these dynamic properties are considered in the design of the feedback controller. All the designs are made in the continuous domain and are digitalized by applying the proper sampling period. The system is simulated for the two cases of power increase and decrease. From the results of simulation, it is found that the controller constants would rather be invariable during the power increase, while for the case of power decrease they should be changed with the power variation to keep the system stability.

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Effects of Plant Age and Cultural Conditions on Leaf Shape of Korean Ginseng (년생 및 재배조건이 인삼의 엽형에 미치는 영향)

  • 이종철;최창렬
    • Journal of Ginseng Research
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    • v.8 no.2
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    • pp.178-183
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    • 1984
  • This study was conducted to know the influence of plant age and cultural conditions such as plant population density and light intensity under the shading on the leaf shape of panax ginseng. The result obtained were as follows; 1) Leaf length(L)/maximum width(W) was no difference with different age of over 3-over 3year old plant, but that of 1 or 2-yearold was smaller than those of over 3-year old. The values of L/W showed in the order of 2 or 4,3, 1 or 5 leaflet. 2) Ratios of leaflet area to leaf area were 32.0% in leaflet 3, from 209.% to 27.9% in leaflet 2 or 4, and from 6.5% to 7.1% in leaflet 1 or 5. 3) The coefficients of variability for L/W and ratio of leaflet area to leaf area of leaflet 3 were smallest among leaflets. 4) There were significant differences between largest and smallest leaflet 3, leaf areas and ratio of leaflet 3 area to leaf area in same plant. 5) LW and ratio of leaflet 3 area to leaf area were not affected by plant population density. 6) It showed a tendency that the L/W was increased with increasing the light transmittance rate (LTR). The ratio of leaflet 3 area to leaf area of ginseng grown under 20% LTR was not different comparing to that of plant grown under 5% LTR, but it was significantly increased in plant grown at 100% LTR.

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The Regulatory Role of 5-Lipoxygenase in Mature Osteoclasts (5-Lipoxygenase에 의한 성숙 파골세포의 조절)

  • Noh, A Long Sae Mi;Moon, Miran;Jeong, Ji-Eun;Yim, Mijung
    • YAKHAK HOEJI
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    • v.56 no.6
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    • pp.347-351
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    • 2012
  • 5-Lipoxygenase (5-LO) catalyzes the formation of two major groups of leukotrienes, LTB4 and cysteinyl leukotrienes (CysLT), and it has been implicated as a promising drug target to treat various inflammatory diseases. Since its role in mature osteoclasts (mOCs) had not been reported, we investigated the effect of 5-LO inhibitors on mOCs. We showed that 5-LO inhibitors dose-dependently decreases the number of mOCs. The effects of 5-LO inhibitors were reversible, suggesting that they did not cause any cellular damages in mOCs. We further demonstrated that the suppression of mOCs by 5-LO inhibitors was caused mainly by disruption of the actin ring formation. Similar effects were shown with CysLT receptor (CysLTR)1 antagonist in mOCs. The mRNA expression of CysLTR1 and the production of CysLT were increased in mOCs. These results indicate that CysLTR1 mediates the suppression of mOCs by 5-LO inhibitors. Taken together, this study demonstrated that 5-LO plays important role in mOCs and possibly a novel therapeutic target for bone resorption diseases.

End-Point Position Control of a Flexible Manipulator (유연한 조작기의 끝점 위치 제어)

  • 이재원;주해호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.7
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    • pp.1307-1313
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    • 1992
  • The end-point position control of a flexible manipulator is a non-minimum phase system. The PD feedback of the end-point position is not stable in contrast with that of the hub jangle. However, the system can be stabilized conditionally by the feedback of both the hub rate angle and the end-point position. Even in the non-minimum system, the LQG/LTR control law is more systmatic controller design method than the classical control law which uses a root-locus technique.

The Robust Controller Design for Lateral Control of Vehicles (차량의 횡방향 모델에 대한 강인 제어기 설계)

  • 김은주;하성기;정승권;이만형
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.04a
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    • pp.496-499
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    • 2002
  • The LQG/LTR controller is a robust and stable control which is systematic method with a view of engineering. And the H$^{\infty}$ scheme is adopted for the design of the controller to reduce the effects of the disturbances. In this paper, LQG/LTR and H$^{\infty}$ Controller Design of Lateral Control System for an Automobile is developed with 3 DOF (degree-of-freedom) model. The performance has been compared for the employed two types of controllers via computed simulations. The results show that the H$^{\infty}$ controller provides more robustness property for the disturbances and lower control input.

The Robust Controller Design for Lateral Control of Vehicles (차량의 횡방향 모델분석 및 제어기 설계)

  • 김은주;하성기;배종일;이만형
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.318-321
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    • 2002
  • The LQG/LTR controller is a robust and stable control which is systematic method with a view of engineering. And the H$^{\infty}$ scheme is adopted for the design of the controller to reduce the effects of the disturbances. In this paper, LQG/LTR and H$^{\infty}$ Controller Design of Lateral Control System for an Automobile is developed with 3 DOF (degree-of-freedom) model. The performance has been compared for the employed two types of controllers via computed simulations. The results show that the H$^{\infty}$ controller provides more robustness property for the disturbances and lower control input.

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차량 능동 현가장치의 혼합제어기 설계

  • 한기봉;이시복
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1993.10a
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    • pp.293-298
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    • 1993
  • In ground vehicles, the increasing demand for safety and ride comfort which are trade-off relation, especially at high speeds, has led to the development od actively controlled suspensions. The LQG/LTR controller can be used to design a robust feedback control system that deals with disturbance rejection properties as well as insensitivity to modelling errors and sensor noise. And when the disturbance can not be measured but is limited within a certain frequency range, a bandpass feedback to eliminate the disturbance response can be used. In this paper, hybrid controller cosisted of bandpass feedback controller and LQG/LTR controller is applied to a quarter-car model moving on a randomly profiled road. The random road profile considered as colored noise is shaped from white noise by use of shaping filter. The performance of the hybrid control system is compared with that of an LQG/LTR controlled system.

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Motion Control of the Precise Stage using Piezoelectric Actuator (압전소자를 이용한 정밀 스테이지의 운동제어)

  • Kim, In-Soo;Kim, Yeung-Shik;Hwang, Yun-Sik
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.4
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    • pp.102-108
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    • 2011
  • LQG/LTR control scheme is applied to the two axes stage using piezoelectric actuator for tracking reference input and suppressing hysteresis effect in this paper. The plant is combined with an integrator to improve the tracking ability. LQG/LTR controller is designed by making desirable target filter loop remove all poles except for an integrator included in new design plant model and loop transfer recovery. Decoupler in the shape of FIR filter is added to remove the coupling effect between the two axes motion and so feedback control loop is designed independently for the each axis motion.

LTR properties for output-delayed systems (출력 시간 지연 시스템의 루우프 복구특성)

  • 이상정;홍석민
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10a
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    • pp.161-167
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    • 1993
  • This paper presents robustness properties of the Kalman Filter ad the associated LQG/LTR method for linear time-invariant systems having delays in both the state and output. A circle condition relating to the return difference matrix associated with the Kalman filter is derived. Using this circle condition, it is shown that the Kalman filter guarantees(1/2, .inf.) gain margin and .+-.60.deg. phase margin, which are the same as those for nondelay systems. However, it is shown that, even for minimum phase plants, the LQG/LTR method can not recover the target loop transfer function. Instead, an upper bound on the recovery error is obtained using an upper bound of the solution of the Kalman filter Riccati equations. Finally, some dual properties between output-delated system and input-delayed systems are exploited.

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