• Conference Object  

      Bond graph based modal decomposition of systems with non-proportional damping 

      Louca, Loucas S. (Affiliation: Department of Mechanical and Manufacturing Engineering, University of Cyprus, 75 Kallipoleos Street, Nicosia 1678, CyprusCorrespondence Address: Louca, L.S.Department of Mechanical and Manufacturing Engineering, University of Cyprus, 75 Kallipoleos Street, Nicosia 1678, Cyprusemail: lslouca@ucy.ac.cy, 2012)
      Modal analysis of lumped parameter and continuous dynamic linear systems is extensively used to study their dynamic behavior and controller design. In both cases, a reduction of the model size that does not degrade accuracy ...
    • Conference Object  

      Bond graph based modal representations and model reduction of lumped parameter systems 

      Louca, Loucas S. (Affiliation: Department of Mechanical and Manufacturing Engineering, University of Cyprus, 75 Kallipoleos Street, Nicosia 1678, CyprusCorrespondence Address: Louca, L.S.Department of Mechanical and Manufacturing Engineering, University of Cyprus, 75 Kallipoleos Street, Nicosia 1678, Cyprusemail: lslouca@ucy.ac.cy, 2006)
      Modal analysis is extensively used to study dynamic behavior of continuous and lumped parameter linear systems. More specifically, modal analysis can be used for the analysis and controller design of dynamic systems. In ...
    • Article  

      Bounds on the size of minimal nonnegative realizations for discrete-time LTI systems 

      Hadjicostis, Christoforos N. (1999)
      Nonnegative linear time-invariant (LTI) state-space models are characterized by the property that their state variables and outputs remain nonnegative whenever the initial state and the inputs are nonnegative. Necessary ...
    • Conference Object  

      Complexity of distributed parameter bond graph models 

      Louca, Loucas S. (The Society for Modeling and Simulation International, 2014)
      Modeling metrics and algorithms that assist the development of dynamic system models are essential for efficient use of modeling and simulation in everyday engineering tasks. Various modeling procedures have been proposed ...
    • Conference Object  

      Control of discrete-time partially-observed jump linear systems over causal communication systems 

      Denic, S. Z.; Charalambous, Charalambos D. (2006)
      We consider the problem of control of discrete-time partially-observed jump linear system over a noisy causal communication channel. Necessary conditions for observability and stabilizability in probability and r-th mean ...
    • Conference Object  

      Control of jump linear systems over jump communication channels - Source-channel matching approach 

      Donic, S. Z.; Charalambous, Charalambos D. (2007)
      The control of partially observed jump linear systems over jump communication channels is investigated when the Plant State Information (I*SI) and the Channel Slate Information (CSI) are present at the transmitter and the ...
    • Conference Object  

      Control of quantized multi-agent systems with linear nearest neighbor rules: A finite field approach 

      Sundaram, S.; Hadjicostis, Christoforos N. (2010)
      We study the problem of controlling a multi-agent system where each agent is only allowed to be in a discrete and finite set of states. Each agent is capable of updating its state based on the states of its neighbors, and ...
    • Conference Object  

      Designing stable inverters and state observers for switched linear systems with unknown inputs 

      Sundaram, S.; Hadjicostis, Christoforos N. (2006)
      We present a method for estimating the inputs and states in discrete-time switched linear systems with unknown inputs. We first investigate the problem of system invertibility, which reconstructs the unknown inputs based ...
    • Conference Object  

      Encoder, controller and decoder design of jump linear systems over jump communication channels 

      Ma, X.; Djouadi, S.; Charalambous, Charalambos D.; Denic, S. (2013)
      In this work, we focus on the encoder, decoder, and controller design for jump linear systems over jump communication channels.The plant state information (PSI) and the channel state information (CSI) are assumed to be ...
    • Conference Object  

      Feedback control over packet dropping network links 

      Mo, H.; Hadjicostis, Christoforos N. (2007)
      This paper studies stabilization schemes for a discrete-time control systems in which the feedback loop includes a network link that may suffer packet drops. We model the packet dropping network link as an erasure channel ...
    • Article  

      A Frequency-Based Interpretation of Energy-Based Model Reduction of Linear Systems 

      Louca, Loucas S. (2016)
      Various modeling techniques have been proposed in order to make modeling a more systematic procedure and to facilitate the development of modeling software that provide users, even experienced users, more ease when developing ...
    • Conference Object  

      Information dissemination in networks via linear iterative strategies over finite fields 

      Sundaram, S.; Hadjicostis, Christoforos N. (2009)
      Given an arbitrary network of interconnected nodes, each with an initial value from a discrete set, we consider the problem of distributively disseminating these initial values under the constraint that the nodes can only ...
    • Article  

      Magnetohydrodynamic turbulence at moderate magnetic Reynolds number 

      Knaepen, B.; Kassinos, Stavros C.; Carati, D. (2004)
      We consider the case of homogeneous turbulence in a conducting fluid that is exposed to a uniform external magnetic field at low to moderate magnetic Reynolds numbers (by moderate we mean here values as high as 20). When ...
    • Conference Object  

      Model reduction of modal representations 

      Louca, Loucas S.; Xydas, E. (American Society of Mechanical Engineers (ASME), 2006)
      Dynamic analysis is extensively used to study the behavior of continuous and lumped parameter linear systems. In addition to the physical space, analyses can also be performed in the modal space where useful frequency ...
    • Conference Object  

      Non-concurrent error detection and correction in discrete-time LTI dynamic systems 

      Hadjicostis, Christoforos N. (2001)
      In this paper we develop fault-tolerant constructions for discrete-time (DT) linear time-invariant (LTI) dynamic systems that are build out of appropriately interconnected delay, adder and gain elements. More specifically, ...
    • Conference Object  

      On optimal performance for linear time-varying systems 

      Djouadi, S. M.; Charalambous, Charalambos D. (2004)
      In this paper we consider the optimal disturbance attenuation problem and robustness for linear time-varying (LTV) systems. This problem corresponds to the standard optimal H ∞ problem for LTI systems. The problem is ...
    • Conference Object  

      Optimal state estimators for linear systems with unknown inputs 

      Sundaram, S.; Hadjicostis, Christoforos N. (2006)
      We present a method for constructing linear minimum-variance unbiased state estimators for discrete-time linear stochastic systems with unknown inputs. Our design provides a characterization of estimators with delay, which ...
    • Article  

      Partial state observers for linear systems with unknown inputs 

      Sundaram, S.; Hadjicostis, Christoforos N. (2008)
      We consider the problem of constructing partial state observers for discrete-time linear systems with unknown inputs. Specifically, for any given system, we develop a design procedure that characterizes the set of all ...
    • Article  

      Performance analysis for a changepoint problem 

      Hibey, J. L.; Charalambos, C. 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. ...
    • Conference Object  

      Robust control over uncertain communication channels 

      Charalambous, Charalambos D.; Farhadi, A.; Denic, S.; Rezaei, F. (2005)
      In this paper, the mathematical framework for studying robust control over uncertain communication channels is introduced. The theory is developed by generalizing the classical information theoretic measures of information ...