• 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 number of markings consistent with label observations in petri nets 

      Ru, Y.; Hadjicostis, Christoforos N. (2009)
      In this paper, we consider state estimation in discrete-event systems (DESs) modeled by labeled Petri nets and present upper bounds on the number of system states (or markings) that are consistent with an observed sequence ...
    • 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 ...
    • Article  

      Decreased centrality of cortical volume covariance networks in autism spectrum disorders 

      Balardin, J. B.; Comfort, W. E.; Daly, Eileen M.; Murphy, Clodagh M.; Andrews, Derek Sayre; Murphy, Declan G. M.; Ecker, C.; Sato, J. R.; Bailey, Anthony J.; Baron-Cohen, Simon; Bolton, P. F.; Bullmore, Edward T.; Carrington, S.; Catani, Marco; Chakrabarti, B.; Craig, Michael C.; Daly, Eileen M.; Deoni, Sean C. L.; Happé, Francesca; Henty, Julian; Jezzard, Peter; Johnston, Patrick; Jones, D. K.; Lai, Meng-Chuan; Lombardo, Michael V.; Madden, A.; Mullins, D.; Murphy, Clodagh M.; Murphy, Declan G. M.; Pasco, Greg; Ruigrok, Amber N. V.; Sadek, Susan A.; Spain, D.; Stewart, R.; Suckling, John; Wheelwright, Sally J.; Williams, Steven C. R.; Wilson, C. E.; MRC AIMS Consortium (2015)
      Autism spectrum disorders (ASD) are a group of neurodevelopmental conditions characterized by atypical structural and functional brain connectivity. Complex network analysis has been mainly used to describe altered ...
    • 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  

      Distributed Balancing of Commodity Networks Under Flow Interval Constraints 

      Hadjicostis, Christoforos N.; Domínguez-Garcia, A. D. (2018)
      We consider networks the nodes of which are interconnected via directed edges, each able to admit a flow (or weight) within a certain interval, with nonnegative end points that correspond to lower and upper flow limits. ...
    • Article  

      Distributed cycle detection and removal 

      Oliva, G.; Setola, R.; Glielmo, L.; Hadjicostis, Christoforos N. (2018)
      In this paper, we provide distributed algorithms to detect and remove cycles in a directed relational graph by exploiting the underlying undirected communication graph; the relational graph models a relation among the ...
    • Article  

      Distributed Finite-Time Average Consensus in Digraphs in the Presence of Time Delays 

      Charalambous, T.; Yuan, Y.; Yang, T.; Pan, W.; Hadjicostis, Christoforos N.; Johansson, M. (2015)
      Most algorithms for distributed averaging only guarantee asymptotic convergence. This paper introduces a distributed protocol that allows nodes to find the exact average of the initial values in a finite and minimum number ...
    • Article  

      Distributed finite-time calculation of node eccentricities, graph radius and graph diameter 

      Oliva, G.; Setola, R.; Hadjicostis, Christoforos N. (2016)
      The distributed calculation of node eccentricities, graph radius and graph diameter are fundamental steps to tune network protocols (e.g., setting an adequate time-to-live of packets), to select cluster heads, or to execute ...
    • Article  

      Distributed resource coordination in networked systems described by digraphs 

      Domínguez-Garcia, A. D.; Hadjicostis, Christoforos N. (2015)
      We consider a multicomponent system in which each component can receive/transmit information from/to components in its immediate neighborhood. Communication links between components are not required to be bidirectional, ...
    • Article  

      Distributed weight balancing over digraphs 

      Rikos, A. I.; Charalambous, T.; Hadjicostis, Christoforos N. (2014)
      A weighted digraph is balanced if, for each node, the sum of the weights of the edges outgoing from that node is equal to the sum of the weights of the edges incoming to that node. Weight-balanced digraphs play a key role ...
    • Article  

      Extension and application of an algorithm for systematic identification of weak coupling and partitions in dynamic system models 

      Rideout, D. G.; Stein, J. L.; Louca, Loucas S. (2009)
      This paper reviews and extends a technique to detect weak coupling (one-way coupling or complete decoupling) among elements of a dynamic system model, and to partition and reduce models in which weak coupling is found. The ...
    • Article  

      Fault diagnosis in discrete event systems modeled by partially observed petri nets 

      Ru, Y.; Hadjicostis, Christoforos N. (2009)
      In this paper, we study fault diagnosis in discrete event systems modeled by partially observed Petri nets, i.e., Petri nets equipped with sensors that allow observation of the number of tokens in some of the places and/or ...
    • Conference Object  

      Fault diagnosis in discrete event systems modeled by petri nets with outputs 

      Ru, Y.; Hadjicostis, Christoforos N. (2008)
      In this paper, we study fault diagnosis in discrete event systems modeled by Petri nets with outputs, i.e., Petri nets with place sensors and transition sensors. Faults are modeled as unobservable transitions and are divided ...
    • Conference Object  

      Fault model identification with petri nets 

      Cabasino, M. P.; Giua, A.; Hadjicostis, Christoforos N.; Seatzu, C. (2008)
      Most of the fault identification problems in the Discrete Event Systems literature assume knowledge of the structure of the net system, including the nature (and behavior) of the possible faults. In this paper we deal with ...
    • Conference Object  

      Fault-tolerant supervisory control of discrete event systems modeled by bounded Petri nets 

      Ru, Y.; Hadjicostis, Christoforos N. (2007)
      This paper considers bounded Petri nets with both controllable and uncontrollable transitions, and addresses the synthesis of a fault-tolerant supervisor in a setting where the control specifications are described via ...
    • Article  

      Finite segment model complexity of an Euler-Bernoulli beam 

      Louca, Loucas S. (2015)
      A common approach for modeling the dynamic behavior of distributed parameter systems is the approximation through finite-segment models. These models are able to accurately predict the dynamic behavior of the system given ...
    • Doctoral Thesis  Open Access

      Graph design using knowledge-driven, self-adaptive multi-objective evolutionary graph algorithms 

      Nicolaou, Christodoulos A. (Πανεπιστήμιο Κύπρου, Σχολή Θετικών και Εφαρμοσμένων Επιστημών / University of Cyprus, Faculty of Pure and Applied Sciences, 2010-06)
      Ο Σχεδιασμός Βέλτιστου Γραφήματος (ΣΒΓ) είναι ένα κοινό πρόβλημα που συναντάτε σε ποικίλα ερευνητικά πεδία όπως τον σχεδιασμό δικτύων επικοινωνιών και συγκοινωνιών, και την ανακάλυψη νέων φαρμάκων. Συχνά τα γραφήματα που ...
    • Article  

      Graphical inference for multiple intrusion detection 

      Le, T.; Hadjicostis, Christoforos N. (2008)
      In this paper, we consider vulnerabilities of networked systems and develop a multiple intrusion detection system (MIDS) which operates by running belief propagation on an appropriately constructed weighted bipartite graph. ...