• Article  

      Adaptive mixing control with multiple estimators 

      Baldi, S.; Ioannou, Petros A.; Kosmatopoulos, E. B. (2012)
      A recently proposed adaptive control scheme with mixing involves the use of precalculated candidate controllers whose output is weighted on the basis of the parameter estimates generated by an online parameter estimator. ...
    • Article  

      Designs of bisimilar Petri net controllers with fault tolerance capabilities 

      Li, L.; Hadjicostis, Christoforos N.; Sreenivas, R. S. (2008)
      This paper proposes an approach for providing tolerance against faults that may compromise the functionality of a given controller modeled by a Petri net. The method is based on embedding the given Petri net controller ...
    • Article  

      Directly computable L2 and L∞ performance bounds for morse's dynamic certainty equivalence adaptive controller 

      Datta, Aniruddha; Ioannou, Petros A. (1995)
      In this paper we consider a model reference adaptive control scheme where the classical error augmentation and standard tuning error normalization are avoided through the use of Morse's high‐order tuner. We consider the ...
    • Article  

      Dynamical neural networks that ensure exponential identification error convergence 

      Kosmatopoulos, E. B.; Christodoulou, Manolis A.; Ioannou, Petros A. (1997)
      Classical adaptive and robust adaptive schemes, are unable to ensure convergence of the identification error to zero, in the case of modeling errors. Therefore, the usage of such schemes to 'black-box' identification of ...
    • Conference Object  

      Evaluation of likelihood-ratio and performance bounds for nonlinear decision problems via stochastic PDE 

      Charalambous, Charalambos D.; Hibey, Joseph L. (American Automatic Control Council, 1994)
      The nonlinear binary decision problem with signal satisfying a diffusion equation observed through noisy measurements is considered. Using the unnormalized conditional density of nonlinear filtering, expressions for ...
    • Conference Object  

      Fault-tolerant linear finite state machines 

      Hadjicostis, Christoforos N.; Verghese, G. C. (Institute of Electrical and Electronics Engineers Inc., 1999)
      In this paper we develop a framework for constructing fault-tolerant dynamic systems, focusing primarily on linear finite state machines (LFSMs). Modular redundancy, the traditional approach to fault tolerance, is expensive ...
    • Conference Object  

      Heteroskedastic linear regression: Steps towards adaptivity, efficiency, and robustness 

      Politis, Dimitris Nicolas; Poulis, S. (Springer New York LLC, 2014)
      In linear regression with heteroscedastic errors, the Generalized Least Squares (GLS) estimator is optimal, i.e., it is the Best Linear Unbiased Estimator (BLUE). The Ordinary Least Squares (OLS) estimator is suboptimal ...
    • Conference Object  

      Hidden markov model classification based on empirical frequencies of observed symbols 

      Keroglou, C.; Hadjicostis, Christoforos N. (IFAC Secretariat, 2014)
      Given a sequence of observations, classification among two known hidden Markov models (HMMs) can be accomplished with a classifier that minimizes the probability of error (i.e., the probability of misclassification) by ...
    • Article  

      Measuring the impact of adversarial errors on packet scheduling strategies 

      Fernández Anta, Antonio; Georgiou, Chryssis; Kowalski, D. R.; Widmer, J.; Zavou, Elli (2013)
      In this paper we explore the problem of achieving efficient packet transmission over unreliable links with worst case occurrence of errors. In such a setup, even an omniscient offline scheduling strategy cannot achieve ...
    • Article  

      Measuring the impact of adversarial errors on packet scheduling strategies 

      Fernández Anta, A.; Georgiou, Chryssis; Kowalski, D. R.; Widmer, J.; Zavou, Elli (2016)
      In this paper, we explore the problem of achieving efficient packet transmission over unreliable links with worst-case occurrence of errors. In such a setup, even an omniscient offline scheduling strategy cannot achieve ...
    • Article  

      A meshless numerical identification of a sound-hard obstacle 

      Karageorghis, Andreas; Lesnic, D. (2012)
      We propose a simple meshless method for detecting a rigid (sound-hard) scatterer embedded in a host acoustic homogeneous medium from scant measurements of the scattered near field. This inverse problem is ill-posed since ...
    • Article  

      Multichannel deconvolution with long range dependence: Upper bounds on the Lp-risk (1 ≤ p < ∞) 

      Kulik, R.; Sapatinas, Theofanis; Wishart, J. R. (2015)
      We consider multichannel deconvolution in a periodic setting with long-memory errors under three different scenarios for the convolution operators, i.e., super-smooth, regular-smooth and box-car convolutions. We investigate ...
    • Conference Object  

      A new robust adaptive control scheme for linear time varying plants 

      Fidan, B.; Zhang, Y.; Ioannou, Petros A. (2002)
      In a recent work, a new linear adaptive controller based on certainty-equivalence and backstepping design, which promises a level of transient and asymptotic performance comparable to that of the tuning functions adaptive ...
    • Conference Object  

      Nonlinear control design for linear time varying systems 

      Zhang, Youping; Ioannou, Petros A. (1996)
      A new class of linear controllers for linear time varying systems are proposed. These controllers are based on nonlinear tools such as integrator backstepping and nonlinear damping, and on a new filter structure that ...
    • Article  

      Performance analysis for a changepoint problem 

      Hibey, J. L.; Charalambous, Charalambos D. (1999)
      Nonlinear stochastic differential equations are used to model a version of the changepoint problem. State estimates of the minimum mean-square-error-type are used in likelihood-ratio tests to detect the time of change. ...
    • Article  

      Robustness of nonlinear control systems with respect to unmodeled dynamics 

      Zhang, Y.; Ioannou, Petros A. (1999)
      In theory, it can be established that nonlinear control laws for linear or nonlinear plants can be used to meet strict performance requirements. The success of these control designs in practical situations will very much ...
    • Article  

      Teachers' Attitudes Towards Their Pupils' Mathematical Errors 

      Gagatsis, Athanasios; Kyriakides, Leonidas (2000)
      This article is mainly concerned with the didactical and the epistemological approach towards pupils' errors in mathematics. The findings of an investigation into a representative sample of Cypriot teachers' attitudes of ...