• Title/Summary/Keyword: state control

Search Result 9,371, Processing Time 0.041 seconds

The System and Activity of Port State Control in Japan

  • Ichikawa, Yoshiro
    • Proceedings of KOSOMES biannual meeting
    • /
    • 2000.05a
    • /
    • pp.86-100
    • /
    • 2000
  • The author of this document is generally in charge of Port State Control affairs at the headquarters of Ministry of Transport, Japan. In this document, the necessity of Port State Control, the brief history of japanese Port State Control and the present system of Port State Control in Japan are introduced. Also, the newest output of Japanese Port State Control which is an annual statistic of 1999 is explained, subsequently the policy and strategy on Port State Control in Japan is introduced.

  • PDF

Cytosolic prion protein induces apoptosis in human neuronal cell SH-SY5Y via mitochondrial disruption pathway

  • Wang, Xin;Dong, Chen-Fang;Shi, Qi;Shi, Song;Wang, Gui-Rong;Lei, Yan-Jun;Xu, Kun;An, Run;Chen, Jian-Ming;Jiang, Hui-Ying;Tian, Chan;Gao, Chen;Zhao, Yu-Jun;Han, Jun;Dong, Xiao-Ping
    • BMB Reports
    • /
    • v.42 no.7
    • /
    • pp.444-449
    • /
    • 2009
  • Different neurodegenerative disorders like prion disease, is caused by protein misfolding conformers. Reverse-transfected cytosolic prion protein (PrP) and PrP expressed in the cytosol have been shown to be neurotoxic. To investigate the possible mechanism of neurotoxicity due to accumulation of PrP in cytosol, a PrP mutant lacking the signal and GPI (CytoPrP) was introduced into the SH-SY5Y cell. MTT and trypan blue assays indicated that the viability of cells expressing CytoPrP was remarkably reduced after treatment of MG-132. Obvious apoptosis phenomena were detected in the cells accumulated with CytoPrP, including loss of mitochondrial transmembrane potential, increase of caspase-3 activity, more annexin V/PI-double positive-stained cells and reduced Bcl-2 level. Moreover, DNA fragmentation and TUNEL assays also revealed clear evidences of late apoptosis in the cells accumulated CytoPrP. These data suggest that the accumulation of CytoPrP in cytoplasm may trigger cell apoptosis, in which mitochondrial relative apoptosis pathway seems to play critical role.

A VSR $\bar{X}$ Chart with Multi-state VSS and 2-state VSI Scheme

  • Lee, Jae-Heon;Park, Chang-Soon
    • Journal of Korean Society for Quality Management
    • /
    • v.32 no.4
    • /
    • pp.252-264
    • /
    • 2004
  • Variable sampling Interval (VSI) control charts vary the sampling interval according to value of the control statistic while the sample size is fixed. It is known that control charts with 2-state VSI scheme, which uses only two sampling intervals, give good statistical properties. Variable sample size (VSS) control charts vary the sample size according to value of the control statistic while the sampling interval is fixed. In the VSS scheme no optimal results are known for the number of sample sizes. It is also known that the variable sampling rate (VSR) $\bar{X}$ control chart with 2-state VSS and 2-state VSI scheme leads to large improvements In performance over the fixed sampling rate (FSR) $\bar{X}$ chart, but the optimal number of states for sample size Is not known. In this paper, the VSR Χ charts with multi-state VSS and 2-state VSI scheme are designed and compared to 2-state VSS and 2-state VSI scheme. The multi-state VSS scheme is considered to, achieve an additional improvement by switching from the 2-state VSS scheme. On the other hand, the multi-state VSI scheme is not considered because the 2-state scheme is known to be optimal. The 3-state VSS scheme improves substantially the sensitivity of the $\bar{X}$ chart especially for small and moderate mean shifts.

Optimal Sliding-Mode Controller Design based on State Observer (관측기 기반 하의 최적 슬라이딩 모드 제어기 설계)

  • Hong, Min-Suk;You, Kwan-Ho
    • Proceedings of the KIEE Conference
    • /
    • 2005.05a
    • /
    • pp.119-121
    • /
    • 2005
  • The sliding-mode control technique could make a system unstable which external disturbance and uncertainty exists in. This paper suggests a robust sliding-mode control algorithm which can be applied to a linear system with parameter uncertainties. To reduce the chattering effect, the whole system is comprised of using a state variable in which the state's estimated value is added. The condition of estimated state results from state observer. The proposed control algorithm uses the optimal feedback controller following the dynamic system equation which consists of a state variable resulting from its own state variable, controller input, estimated state variable. Through comparison with the time optimal control algorithm using simulation, the suggested algorithm shows the improved stability and robustness while it manifests the fast tracking characteristics.

  • PDF

Gain Scheduled State Feedback and Disturbance Feedforward Control for Systems with Bounded Control Input (제어입력 크기제한을 갖는 시스템에서 이득 스케쥴 상태되먹임-외란앞먹임 제어)

  • Kang, Min-Sig
    • Proceedings of the KSME Conference
    • /
    • 2007.05a
    • /
    • pp.915-920
    • /
    • 2007
  • A new optimal state feedback and disturbance feedforward control design in the sense of minimizing $L_{2}-gain$ from disturbance to control output is proposed for disturbance attenuation of systems with bounded control input and measurable disturbance. The controller is derived in the framework of linear matrix inequality(LMI) optimization. A gain scheduled state feedback and disturbance feedforward control design is also suggested to improve disturbance attenuation performance. The control gains are scheduled according to the proximity to the origin of the state of the plant and the magnitude of disturbance. This procedure yields a stable linear time varying control structure that allows higher gain and hence higher performance controller as the state and the disturbance move closer to the origin. The main results give sufficient conditions for the satisfaction of a parameter-dependent performance measure, without violating the bounded control input condition.

  • PDF

Gain Scheduled State Feedback and Disturbance Feedforward Control for Systems with Bounded Control Input - Theory (제어입력 크기제한을 갖는 시스템에서 이득 스케줄 상태되먹임-외란앞먹임 제어 - 이론)

  • Kang, Min-Sig
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.24 no.11
    • /
    • pp.59-65
    • /
    • 2007
  • A new optimal state feedback and disturbance feedforward control design in the sense of minimizing $L_2$-gain from disturbance to control output is proposed for disturbance attenuation of systems with bounded control input and measurable disturbance. The controller is derived in the framework of linear matrix inequality(LMI) optimization. A gain scheduled state feedback and disturbance feedforward control design is also suggested to improve disturbance attenuation performance. The control gains are scheduled according to the proximity to the origin of the state of the plant and the magnitude of disturbance. This procedure yields a stable linear time varying control structure that allows higher gain and hence higher performance controller as the state and the disturbance move closer to the origin. The main results give sufficient conditions for the satisfaction of a parameter-dependent performance measure, without violating the bounded control input condition.

Some Universal Characteristics of Intertidal Bacterial Diversity as Revealed by 16S rRNA Gene-Based PCR Clone Analysis

  • Shuang, J.L.;Liu, C.H.;An, S.Q.;Xing, Y.;Zheng, G.Q.;Shen, Y.F.
    • Journal of Microbiology and Biotechnology
    • /
    • v.16 no.12
    • /
    • pp.1882-1889
    • /
    • 2006
  • A 16S rDNA clone library was generated to investigate the bacterial diversity in intertidal sediment from the coast of the Yellow Sea, P. R. China. A total of 102 clones were sequenced and grouped into 73 OTUs using a phylogenetic approach. The sequenced clones fell into 11 bacterial lineages: Proteobacteria, Bacteroidetes, Planctomycetes, Chloroflexi, Acidobacteria, Actinobacteria, Firmicutes, Spirochaetes, and candidate divisions of BRCl, OP3, and OP1l. Based on a phylogenetic analysis of these bacteria, together with the ten most closely related sequences deposited in the GenBank, it was concluded that intertidal bacteria are most likely derived from marine bacteria with a remarkable diversity, and some are particularly abundant in intertidal sediment.

Sliding Mode Control for Time-delay System using Virtual State (가상 상태를 이용한 시간 지연 시스템의 슬라이딩 모드 제어)

  • 송영삼;권성하;박승규;오도창;정은태
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.341-341
    • /
    • 2000
  • This paper presents a sliding mode control(SMC) design method for single input linear systems with uncertainties and time delay in the state. We define a sliding surface for the augmented system with a virtual state which is defined from the nominal system. We make a virtual state from optimal control input using LOR(Linear Quadratic Regulator) and the states of the nominal system. We construct a controller that combines SMC with optimal controller. The proposed sliding mode controller stabilizes on the overall closed-loop system.

  • PDF

Design of H Repetitive Control Systems using State Feedback (상태 궤환을 이용한 H 반복 제어 시스템 설계)

  • Doh, Tae-Yong
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.20 no.1
    • /
    • pp.6-11
    • /
    • 2014
  • Repetitive control is a specialized control scheme to track and/or attenuate a periodic reference trajectory and/or disturbance. Most researches about repetitive control have been performed in the frequency domain. Recently, several approaches to deal with repetitive control systems in the state space are developed by representing a q filter as a state-space equation. This paper presents a design method of a repetitive control system in the state space to satisfy $H_{\infty}$ performance. The overall system is composed of a plant, a repetitive controller, and a state-feedback controller, which can be converted to a standard form used in $H_{\infty}$ control. A LMI (Linear Matrix Inequality)-based stability condition is derived for fixed state-feedback gains. Under a given q filter, another LMI condition is derived to improve $H_{\infty}$ performance and is employed to find state-feedback gains by solving an optimization problem. Finally, to verify the feasibility of the proposed method, a numerical example is demonstrated.

가변 풍량 유닛에 의한 실내 공간의 온도제어를 위한 공간의 분할 모델과 상태궤환 제어기의 개발에 관한 연구

  • 박세화;신승철
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.13 no.10
    • /
    • pp.947-959
    • /
    • 2001
  • We propose a control scheme to control the indoor zone temperature via variable air volume (VAV) unit. To control the room temperature, state space model of the conditioned zone which is partitioned into nine artificial sectional regions is derived. The nonlinearity of the damper motion and actuator are considered for the practical use in the state space system description. The temperature control of the room temperature is performed by manipulating the degree of openness of the damper in relation to the local room temperature and the supplied air flow rate. In general, since a local temperature in the conditioned zone is measured, it is required to estimate the temperature values in each regions for the precise temperature control. We thus design a state observer to estimate the regional temperature, and use these values in the controller. The overall control system consists of the state observer based state feedback with the integral control. We compared the control results of the proposed scheme with those of cascade proportional and integral (PI) control, and showed that the scheme achieved precise control of the conditioned system.

  • PDF