• 제목/요약/키워드: positive real control

검색결과 215건 처리시간 0.028초

Stabilizing Solutions of Algebraic Matrix riccati Equations in TEX>$H_\infty$ Control Problems

  • Kano, Hiroyuki;Nishimura, Toshimitsu
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
    • /
    • pp.364-368
    • /
    • 1994
  • Algebraic matrix Riccati equations of the form, FP+PF$^{T}$ -PRP+Q=0. are analyzed with reference to the stability of closed-loop system F-PR. Here F, R and Q are n * n real matrices with R=R$^{T}$ and Q=Q$^{T}$ .geq.0 (nonnegative-definite). Such equations have been playing key roles in optimal control and filtering problems with R .geq. 0. and also in the solutions of in H$_{\infty}$ control problems with R taking the form R=H$_{1}$$^{T}$ H$_{1}$-H$_{2}$$^{T}$ H$_{2}$. In both cases an existence of stabilizing solution, i.e. the solution yielding asymptotically stable closed-loop system, is an important problem. First, we briefly review the typical results when R is of definite form, namely either R .geq. 0 as in LQG problems or R .leq. 0. They constitute two extrence cases of Riccati to the cases H$_{2}$=0 and H$_{1}$=0. Necessary and sufficient conditions are shown for the existence of nonnegative-definite or positive-definite stabilizing solution. Secondly, we focus our attention on more general case where R is only assumed to be symmetric, which obviously includes the case for H$_{\infty}$ control problems. Here, necessary conditions are established for the existence of nonnegative-definite or positive-definite stabilizing solutions. The results are established by employing consistently the so-called algebraic method based on an eigenvalue problem of a Hamiltonian matrix.x.ix.x.

  • PDF

Detection of Mycobacterium leprae by Real-time PCR Targeting Mycobacterium leprae-Specific Repetitive Element Sequence

  • Jin, Hyun-Woo;Wang, Hye-Young;Kim, Jong-Pill;Cho, Sang-Nae;Lee, Hye-Young
    • 대한의생명과학회지
    • /
    • 제16권2호
    • /
    • pp.127-131
    • /
    • 2010
  • Mycobacterium leprae detection is difficult even with molecular biological techniques due to the low sensitivity of current methodologies. In this report, real-time PCR targeting the M. leprae-specific repetitive element (RLEP) sequence was developed as a new diagnostic tool and evaluated using clinical specimens. For this, M. leprae DNAs were extracted from skin biopsy specimens from 80 patients and analyzed by real-time PCR using TaqMan probe. Then, the detection efficiency of the real-time PCR was compared with that of standard PCR. In brief, the rate of positive detection by the standard PCR and real-time PCR was 32.50% and 66.25%, respectively. The results seemed to clearly show that the TaqMan real-time PCR developed in this study may be a useful tool for sensitive detection of M. leprae from clinical specimens.

비구조적인 불확실성을 가지는 시스템에 대한 반복 제어기의 설계 (Design of a repetitive controller for the system with unstructured uncertainty)

  • 도태용;문정호;정명진
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
    • /
    • pp.779-782
    • /
    • 1996
  • Repetitive control is a proposed control strategy in view of the internal model principle and achieves a high accuracy asymptotic tracking property by implementing a model that generates the periodic signals of period into the closed-loop system. Since the repetitive control system contains a periodic signal generator with positive feedback loop, which reduces the stability margin, in the overall closed-loop system, the stability of the closed-loop system should be considered as an important problem. In case that a real system has plant uncertainties which are not represented through modeling, the robust stability problem of the repetitive control system has not been considered sufficiently. In this paper, we propose the robust stability condition for the system with modeling uncertainty. The proposed robust stability condition will be obtained using the robust performance condition in the H$_{\infty}$ control. Moreover, by use of the proposed robust stability condition, we propose a procedure that designs a repetitive controller and a feedback controller simultaneously which can stabilize the overall closed-loop system robustly and which can also do the closedloop system without repetitive controller..

  • PDF

Development of a ladder-shape melting temperature isothermal amplification (LMTIA) assay for detection of African swine fever virus (ASFV)

  • Wang, Yongzhen;Wang, Borui;Xu, Dandan;Zhang, Meng;Zhang, Xiaohua;Wang, Deguo
    • Journal of Veterinary Science
    • /
    • 제23권4호
    • /
    • pp.51.1-51.10
    • /
    • 2022
  • Background: Due to the unavailability of an effective vaccine or antiviral drug against the African swine fever virus (ASFV), rapid diagnosis methods are needed to prevent highly contagious African swine fever. Objectives: The objective of this study was to establish the ladder-shape melting temperature isothermal amplification (LMTIA) assay for the detection of ASFV. Methods: LMTIA primers were designed with the p72 gene of ASFV as the target, and plasmid pUC57 was used to clone the gene. The LMTIA reaction system was optimized with the plasmid as the positive control, and the performance of the LMTIA assay was compared with that of the commercial real-time polymerase chain reaction (PCR) kit in terms of sensitivity and detection rate using 200 serum samples. Results: Our results showed that the LMTIA assay could detect the 104 dilution of DNA extracted from the positive reference serum sample, which was the same as that of the commercial real-time PCR kit. The coincidence rate between the two assays was 100%. Conclusions: The LMTIA assay had high sensitivity, good detection, and simple operation. Thus, it is suitable for facilitating preliminary and cost-effective surveillance for the prevention and control of ASFV.

A Real-Time Virtual Re-Convergence Hardware Platform

  • Kim, Jae-Gon;Kim, Jong-Hak;Ham, Hun-Ho;Kim, Jueng-Hun;Park, Chan-Oh;Park, Soon-Suk;Cho, Jun-Dong
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • 제12권2호
    • /
    • pp.127-138
    • /
    • 2012
  • In this paper, we propose a real-time virtual re-convergence hardware platform especially to reduce the visual fatigue caused by stereoscopy. Our unique idea to reduce visual fatigue is to utilize the virtual re-convergence based on the optimized disparity-map that contains more depth information in the negative disparity area than in the positive area. Our virtual re-convergence hardware platform, which consists of image rectification, disparity estimation, depth post-processing, and virtual view control, is realized in real time with 60 fps on a single Xilinx Virtex-5 FPGA chip.

Rapid Detection of Vancomycin-resistance Enterococci by SYBR Green Real-time PCR

  • Yang, Byoung-Seon
    • 대한임상검사과학회지
    • /
    • 제46권2호
    • /
    • pp.64-67
    • /
    • 2014
  • Vancomycin-resistant Enterococci (VRE) are a leading cause of a nosocomial infection. While seven glycopeptide resistance genotypes have been found in Enterococci, vanA and vanB are the most common resistance genotypes. Aims of this study were to detect antibiotic susceptibilities of 23 Enterococcus spp, which broke out in a university hospital by the disk diffusion test, to investigate specific genes of vanA and vanB by conventional and real-time PCR. PCR for vanA and vanB was performed on 23 Enterococci, all 23 were positive for vanA type. This study reports the validation of a simple and rapid VRE detection method that can be easily incorporated into the daily routine of a clinical laboratory. Early detection of VRE strains, including those with susceptibility to Vancomycin, is of paramount clinical importance, as it allows a rapid initiation of strict infection control practices as well as a therapeutic guidance for a confirmed infection. The real-time PCR method is a rapid technique to detect vanA in Enterococci. It is simple and reliable for the rapid characterization of VRE.

비례 방향제어 밸브에 의하여 구동되는 유압실린더-부하계의 단순 적응 위치제어 (Simple Adaptive Position Control of a Hydraulic Cylinder-load System Driven by a Proportional Directional Control Valve)

  • 조승호;이민우
    • 한국정밀공학회지
    • /
    • 제28권8호
    • /
    • pp.936-941
    • /
    • 2011
  • This paper deals with the issue of motion control of a single rod cylinder-load system using simple adaptive control (SAC) method. Prior to controller design, the experiment of open-loop response has been performed. Based on it, design parameters of transfer function are obtained and used for controller design. The effect of parallel feedforward compensator has been investigated by computer simulation, suppressing the oscillatory motion. Through experiments it is conformed that the SAC method gives good tracking performance compared to the PD control method.

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

  • 이영섭
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2004년도 춘계학술대회논문집
    • /
    • pp.587-592
    • /
    • 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.

  • PDF

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

  • 이영섭
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2003년도 추계학술대회논문집
    • /
    • pp.778-783
    • /
    • 2003
  • 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 DVFB control. As a new alternative, a point sensor and piezoelectric actuator pair is also considered, which provides SPR property in all frequency range except at the first resonance in very low frequency. This non-SPR resonance could be minimized by applying a phase lag compensator.

  • PDF

SISO 비선형 시스템의 제어를 위한 퍼지 모델 기반 제어기 (The Fuzzy Model-Based-Controller for the Control of SISO Nonlinear System)

  • 장욱;권오국;주영훈;박진배
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1998년도 하계학술대회 논문집 B
    • /
    • pp.528-530
    • /
    • 1998
  • This paper addresses analysis and design of a fuzzy model-based-controller for the control of uncertain SISO nonlinear systems. In the design procedure, we represent the nonlinear system by using a Takagi-Sugeno fuzzy model and construct a global fuzzy logic controller via parallel distributed compensation and sliding mode control. Unlike other parallel distributed controllers. this globally stable fuzzy controller is designed without finding a common positive definite matrix for a set of Lyapunov equations, and has good tracking performance. Furthermore, stability analysis is conducted not for the fuzzy model but for the real underlying nonlinear system. A simulation is included for the control of the Duffing forced-oscillation system, to show the effectiveness and feasibility of the proposed fuzzy control method.

  • PDF