• Title/Summary/Keyword: control

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Active structural acoustic control using an integrated control system with smart structures

  • Cui, Huaifeng;Hu, Rufu;Chen, Nan
    • Smart Structures and Systems
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    • v.27 no.6
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    • pp.891-901
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    • 2021
  • An integrated control system with smart structure is proposed for active structural acoustic control (ASAC). It is mainly used to integrate the advantages of centralized and decentralized ASAC. Each smart structure contains a relatively independent controller, which forms a distributed control. The coordination and cooperation between smart structures is mainly realized by sending control factors (secondary generalized modal force) from the upper coordination unit (coordination structure) to each smart structure. The control factor can reflect the weight of each smart structure on vibration noise control, and play a key role in noise control. The control factors are extracted from the blend function in the bottom control units (smart structures) and stored in the coordination structure. This design method ensures the consistency of the internal functions of each smart structure and lays a foundation for decentralized control. In addition, whether the control factor is allocated to the smart structure depends on the real-time changes of the sound field. Through the intelligent allocation of the control factors, the global (centralized) control is realized and the coupling problem between smart structures is solved. Since the control system does not have a centralized controller, it appears as a decentralized control in form; at the same time, the centralized control in algorithm is achieved by extracting and redistributing the control factors. Therefore, the control system integrates the advantages of decentralized and centralized control.

Reconfigurable Position Control of Unmanned Expedition Vehicles under the Open Control Platform based Ubiquitous Environment (유비쿼터스 환경에서 개방형 제어 플랫폼에 기반한 무인탐사차량의 재형상 가능 위치제어)

  • Shim Duk-Sun;Yang Cheol-Kwan;Ah Kyu-Seob;Lee Joon-Hak
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.12
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    • pp.1002-1010
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    • 2005
  • We study on the implementation of reconfigurable position control system which is based on Open Control Platform(OCP) for Unmanned Expedition Vehicles(UEV) in ubiquitous environment. The control system uses hierarchical control structure and OCP structure which contains three layers such as core OCP, reconfigurable control API(Application Programmer Interface), generic hybrid control API. The goal of our research is to implement an UEV control system using advanced software technology. As a specific control problem, we study a transition management problem between PID control and neural network control depending on fault or parameter change of the plant, i.e., UEV. The concept of the OCP-based software-enabled control can provide synergy effect by the integration of software component, middleware, network communication, and control, and thus can be applied to various systems in ubiquitous environment.

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
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    • v.42 no.7
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    • pp.444-449
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    • 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 study on the application of the intelligent control algorithms to the flow control system (유량제어계통에 대한 지능형 제어 알고리즘 적용연구)

  • 김동화;조일인
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1792-1795
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    • 1997
  • It is difficulte to control in the flow system because there are many disturbance. So it is impossible to control delicately sometimes by PI or PID. In this paper, we study on the application of intellignet control algorithms such as 2DOF PID control, neural network, Fuzzy contro, Relay feedback to the flow control system. the resultings are 2DOF-PID control is more good response.

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Improved Mold Level Control for Continuous Steel Casting by Fuzzy Logic Control

  • Kueon, Yeongseob;Xiao, Wendong
    • Transactions on Control, Automation and Systems Engineering
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    • v.1 no.1
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    • pp.1-7
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    • 1999
  • This paper gives a simulation study of a new fuzzy logic control(FLC) approach for the mold level control in continuous casting processes. The proposed FLC is PID type hybridizing the conventional fuzzy PI control and Fuzzy PD control with a simplified design scheme. It is shown that, compared with the conventional control, this new control strategy can achieve superior performance for steady-state response and is more robust against process parameter variations and disturbances.

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A Comparison of the performance of mean, median, and precedence control charts for nonnormal data

  • Kim, Jung-Hee;Lee, Sung-Im;Park, Heon-Jin;Lee, Jae-Cheol;Jang, Young-Chul
    • Proceedings of the Korean Statistical Society Conference
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    • 2005.05a
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    • pp.197-201
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    • 2005
  • In this article, we will compare the performance of the mean control chart, the median control chart, the transformed mean control chart, the transformed median control chart, and the precedence control chart by simulation study. For control charts with transformed data, Yeo-Johnson transformation is used. Under the in-control condition, ARL's in all control charts coincide with the designed ARL in the normal distribution, but in the other distributions, only the precedence control chart provides the in-control ARL as designed. Under the out-of-control condition, the mean control chart is preferred in the normal distribution and the median control chart is preferred in the heavy-tailed distribution and the precedence control chart outperforms in the short-tailed distribution.

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Decentralized energy market-based structural control

  • Lynch, Jerome Peter;Law, Kincho H.
    • Structural Engineering and Mechanics
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    • v.17 no.3_4
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    • pp.557-572
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    • 2004
  • Control systems are used to limit structural lateral deflections during large external loads such as winds and earthquakes. Most recently, the semi-active control approach has grown in popularity due to inexpensive control devices that consume little power. As a result, recently designed control systems have employed many semi-active control devices for the control of a structure. In the future, it is envisioned that structural control systems will be large-scale systems defined by high actuation and sensor densities. Decentralized control approaches have been used to control large-scale systems that are too complex for a traditional centralized approach, such as linear quadratic regulation (LQR). This paper describes the derivation of energy market-based control (EMBC), a decentralized approach that models the structural control system as a competitive marketplace. The interaction of free-market buyers and sellers result in an optimal allocation of limited control system resources such as control energy. The Kajima-Shizuoka Building and a 20-story benchmark structure are selected as illustrative examples to be used for comparison of the EMBC and centralized LQR approaches.

Improved Nonlinear Speed Control of PM Synchronous Motor Using Time Delay Control

  • Baik, In-Cheol
    • Journal of Power Electronics
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    • v.3 no.3
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    • pp.197-204
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    • 2003
  • An improved nonlinear speed control of a permanent magnet synchronous motor (PMSM) is presented A quasi-linearized and decoupled model including the influence of parameter variations and speed measurement error on the nonlinear speed control of a PMSM is derived Using this model, to overcome the drawbacks of conventional nonlinear control scheme, the improved nonlinear control scheme which employs time delay control (TDC) scheme is proposed. To show the validity of the proposed control scheme, simulation studies are carried out and compared with the conventional control scheme.

A Method of Select Sequence Control by Remote Control in Process Control designed by SFC (SFC로 설계된 공정제어에서 Remote Control에 의한 선택 시퀀스 제어 방법)

  • You, Jeong-Bong
    • Proceedings of the KIEE Conference
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    • 2007.04a
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    • pp.134-136
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    • 2007
  • Sequential Function Chart(SFC) is very easy to grasp the sequential flow of control logic and has the compatability for a maintenance, In process control, when an error is occurred, to execute other routine by force, we control the process by remote control. In this paper, we proposed the method of select sequence control by remote control in process control designed by Sequential Function Chart(SFC).

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Design of Semi-Active Tendon for Vibration Control of Large Structures (대형 구조물의 진동제어를 위한 반능동형 댐퍼의 설계)

  • Kim, Saang-Bum;Yun, Chung-Bang;Gu, Ja-In
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.11a
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    • pp.282-286
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    • 2000
  • In this paper, magneto-rheological(MR) damper is studied for vibration control of large infra structures under earthquake. Generally, active control devices need a large control force and a high power supply system to reduce the vibration effectively. Large and miss tuned control force may induce the dangerous situation such that the generated large control force acts to amplify the structural vibration. Recently, to overcome the weaknesses of the active control, the semi-active control method is suggested by many researchers. Semi-active control uses the passive control device of which the characteristics can be modified. Control force of the semi-active device is not generated from the actuator with power supply. It is generated as a dynamic reaction force of the device same as in the passive control case, so the control system is inherently stable and robust. Unlike the case of passive control, control force of semi-active control is adjusted depending on the measured response of the structure, so the vibration can be reduced more effectively against various unknown environmental loads. Magneto-rheological(MR) damper is one of the semi-active devices. Dynamic characteristics of the MR material can be changed by applying the magnetic fields. So the control of MR damper needs only small power. Response time of MR to the input voltage is very short, so the high performance control is possible. MR damper has a high force capacity so it is adequate to the vibration control of large infra structure. Because MR damper has a nonlinear property, normal control method used in active control may not be effective. Clipped optimal control, modified bang-bang control etc. have been suggested to MR damper by many researchers. In this study, sliding mode fuzzy control(SMFC) is applied to MR damper. Genetic algorithm is used for the controller tuning. To verify the applicability of MR damper and suggested algorithm, numerical simulation on the aseismic control is carried out. Simulation model is three-story building structure, which was used in the paper of Dyke, et al. The control performance is compared with clipped optimal control. The present results indicate that the SMFC algorithm can reduce the earthquake-induced vibration very effectively.

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