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See detailModel-based optimal PEEP in mechanically ventilated ARDS patients in the Intensive Care Unit
Sundaresan, Ashwath; Chase, J Geoffrey; Shaw, Geoffrey M et al

in Biomedical Engineering Online (2011), 10

Background: The optimal level of positive end-expiratory pressure (PEEP) is still widely debated in treating acute respiratory distress syndrome (ARDS) patients. Current methods of selecting PEEP only ... [more ▼]

Background: The optimal level of positive end-expiratory pressure (PEEP) is still widely debated in treating acute respiratory distress syndrome (ARDS) patients. Current methods of selecting PEEP only provide a range of values and do not provide unique patient-specific solutions. Model-based methods offer a novel way of using non-invasive pressure-volume (PV) measurements to estimate patient recruitability. This paper examines the clinical viability of such models in pilot clinical trials to assist therapy, optimise patient-specific PEEP, assess the disease state and response over time. Methods: Ten patients with acute lung injury or ARDS underwent incremental PEEP recruitment manoeuvres. PV data was measured at increments of 5 cmH(2)O and fitted to the recruitment model. Inspiratory and expiratory breath holds were performed to measure airway resistance and auto-PEEP. Three model-based metrics are used to optimise PEEP based on opening pressures, closing pressures and net recruitment. ARDS status was assessed by model parameters capturing recruitment and compliance. Results: Median model fitting error across all patients for inflation and deflation was 2.8% and 1.02% respectively with all patients experiencing auto-PEEP. In all three metrics' cases, model-based optimal PEEP was higher than clinically selected PEEP. Two patients underwent multiple recruitment manoeuvres over time and model metrics reflected and tracked the state or their ARDS. Conclusions: For ARDS patients, the model-based method presented in this paper provides a unique, non-invasive method to select optimal patient-specific PEEP. In addition, the model has the capability to assess disease state over time using these same models and methods. [less ▲]

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See detailModel-based PEEP optimisation in mechanical ventilation
Chiew, Y. S.; Chase, J. G.; Shaw, G. M. et al

in BioMedical Engineering OnLine (2011), 10

Background: Acute Respiratory Distress Syndrome (ARDS) patients require mechanical ventilation (MV) for breathing support. Patient-specific PEEP is encouraged for treating different patients but there is ... [more ▼]

Background: Acute Respiratory Distress Syndrome (ARDS) patients require mechanical ventilation (MV) for breathing support. Patient-specific PEEP is encouraged for treating different patients but there is no well established method in optimal PEEP selection.Methods: A study of 10 patients diagnosed with ALI/ARDS whom underwent recruitment manoeuvre is carried out. Airway pressure and flow data are used to identify patient-specific constant lung elastance (E <br /> lung) and time-variant dynamic lung elastance (E <br /> drs) at each PEEP level (increments of 5cmH <br /> 2O), for a single compartment linear lung model using integral-based methods. Optimal PEEP is estimated using E <br /> lungversus PEEP, E <br /> drs-Pressure curve and E <br /> drsArea at minimum elastance (maximum compliance) and the inflection of the curves (diminishing return). Results are compared to clinically selected PEEP values. The trials and use of the data were approved by the New Zealand South Island Regional Ethics Committee.Results: Median absolute percentage fitting error to the data when estimating time-variant E <br /> drsis 0.9% (IQR = 0.5-2.4) and 5.6% [IQR: 1.8-11.3] when estimating constant E <br /> lung. Both E <br /> lungand E <br /> drsdecrease with PEEP to a minimum, before rising, and indicating potential over-inflation. Median E <br /> drsover all patients across all PEEP values was 32.2 cmH <br /> 2O/l [IQR: 26.1-46.6], reflecting the heterogeneity of ALI/ARDS patients, and their response to PEEP, that complicates standard approaches to PEEP selection. All E <br /> drs-Pressure curves have a clear inflection point before minimum E <br /> drs, making PEEP selection straightforward. Model-based selected PEEP using the proposed metrics were higher than clinically selected values in 7/10 cases.Conclusion: Continuous monitoring of the patient-specific E <br /> lungand E <br /> drsand minimally invasive PEEP titration provide a unique, patient-specific and physiologically relevant metric to optimize PEEP selection with minimal disruption of MV therapy. © 2011 Chiew et al; licensee BioMed Central Ltd. [less ▲]

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See detailModel-based prediction of the patient-specific response to adrenaline
Chase, J. G.; Starfinger, C.; Hann, C. E. et al

in The open medical informatics journal (2010), 4

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See detailModel-Based Recognition Using Persistent Scatterers
Dudgeon, Dan E.; Verly, Jacques ULg

Scientific conference (1993)

Detailed reference viewed: 6 (1 ULg)
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See detailA model-based relevance estimation approach for feature selection in microarray datasets
Bontempi, Gianluca; Meyer, Patrick ULg

in Artificial Neural Networks-ICANN 2008 (2008)

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See detailModel-based sensor of hemodynamics in critical care
Hann, C. E.; Starfinger, C.; Chase, J. G. et al

in ICST 2007 (2007)

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See detailModel-Based System for Automatic Target Recog- nition from Forward-Looking Laser-Radar Imagery
Verly, Jacques ULg; Delanoy, Richard L.; Dudgeon, Dan E.

in Optical Engineering : The Journal of the Society of Photo-Optical Instrumentation Engineers (1992), 31(12), 2540-2552

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See detailA Model-Based System for Automatic Target Recognition
Verly, Jacques ULg; Delanoy, Richard L.; Dudgeon, Dan E.

Conference (1991, April)

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See detailA Model-Based Target Recognition System
Dudgeon, Dan E.; Delanoy, Richard L.; Verly, Jacques ULg

Scientific conference (1990)

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See detailModel-based therapeutics for the cardiovascular system - a clinical focus
Hann, C. E.; Chase, J. G.; Desaive, Thomas ULg et al

in 6th IFAC Symposium on Modeling and Control in Biomedical Systems (MCBMS09) (2009)

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See detailModel-based verification of a security protocol for conditional access to services
Leduc, Guy ULg; Bonaventure, Olivier; Koerner, Eckhart et al

in Formal Methods In System Design (1999), 14(2), 171-191

We use the formal language LOTOS to specify and verify the robustness of the Equicrypt protocol under design in the European OKAPI project for conditional access to multimedia services. We state some ... [more ▼]

We use the formal language LOTOS to specify and verify the robustness of the Equicrypt protocol under design in the European OKAPI project for conditional access to multimedia services. We state some desired security properties and formalize them. We describe a generic intruder process and its modelling, and show that some properties are falsified in the presence of this intruder. The diagnostic sequences can be used almost directly to exhibit the scenarios of possible attacks on the protocol. Finally, we propose an improvement of the protocol which satisfies our properties. [less ▲]

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See detailModel-based, Automatic Recognition of Tactical Vehicles in Laser-Radar Imagery: Principles and Evaluation
Verly, Jacques ULg; Delanoy, Richard L.; Dudgeon, Dan E.

Conference (1989, November 02)

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See detailModel-free Monte Carlo-like policy evaluation
Fonteneau, Raphaël ULg; Murphy, Susan; Wehenkel, Louis ULg et al

in Proceedings of the Thirteenth International Conference on Artificial Intelligence and Statistics (AISTATS 2010) (2010, May)

We propose an algorithm for estimating the finite-horizon expected return of a closed loop control policy from an a priori given (off-policy) sample of one-step transitions. It averages cumulated rewards ... [more ▼]

We propose an algorithm for estimating the finite-horizon expected return of a closed loop control policy from an a priori given (off-policy) sample of one-step transitions. It averages cumulated rewards along a set of “broken trajectories” made of one-step transitions selected from the sample on the basis of the control policy. Under some Lipschitz continuity assumptions on the system dynamics, reward function and control policy, we provide bounds on the bias and variance of the estimator that depend only on the Lipschitz constants, on the number of broken trajectories used in the estimator, and on the sparsity of the sample of one-step transitions. [less ▲]

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See detailModel-free Monte Carlo-like policy evaluation
Fonteneau, Raphaël ULg; Murphy, Susan A.; Wehenkel, Louis ULg et al

in 29th Benelux Meeting on Systems and Control (2010)

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See detailModel-free Monte Carlo–like policy evaluation
Fonteneau, Raphaël ULg; Murphy, Susan; Wehenkel, Louis ULg et al

in Proceedings of Conférence Francophone sur l'Apprentissage Automatique (CAp) 2010 (2010, May)

We propose an algorithm for estimating the finite-horizon expected return of a closed loop control policy from an a priori given (off-policy) sample of one-step transitions. It averages cumulated rewards ... [more ▼]

We propose an algorithm for estimating the finite-horizon expected return of a closed loop control policy from an a priori given (off-policy) sample of one-step transitions. It averages cumulated rewards along a set of “broken trajectories” made of one-step transitions selected from the sample on the basis of the control policy. Under some Lipschitz continuity assumptions on the system dynamics, reward function and control policy, we provide bounds on the bias and variance of the estimator that depend only on the Lipschitz constants, on the number of broken trajectories used in the estimator, and on the sparsity of the sample of one-step transitions. [less ▲]

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See detailModelaçao numérica da encurvadura lateral de vigas I em aço inoxidável à temperature ambiente e em situaçao de incêndio - comparaçao com o Eurocòdigo
Lopes, N.; Vila Real, P.; Silva, L. et al

in Proceedings of the V Congresso de Construçao Metálica e Mista (2005)

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See detailModelaçao Numérica da Encurvadura Lateral de Vigas I Metalica Sujeitas à Acçao do Fogo
Vila Real, Paulo; Piloto, Paulo; Franssen, Jean-Marc ULg

in Proc. II National Conference on Steel and Composite Construction (1999)

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See detailModelaçao numérica do comportamento de uma estrutura metalica sujeita à acçao do fogo - Analise de varios cenarios de incëndio
Vila Real, P. M. M.; Piloto, P. A. G.; Franssen, Jean-Marc ULg

in Revista Portuguesa de Engenharia de Estruturas (RPEE) (2000), 47

In this work it has been analysed several possible fire scenarios in a steel structure of a commercial building, in order to find which one corresponds to the lowest fire resistance of the structure. It ... [more ▼]

In this work it has been analysed several possible fire scenarios in a steel structure of a commercial building, in order to find which one corresponds to the lowest fire resistance of the structure. It has been used a geometrically and materially non-linear finite element program specially established for the analysis of structures submitted to the fire. As the analysed structure doesn't reach the fire resistance suggested by the Portuguese standards, some solutions are proposed to increase its fire resistance. [less ▲]

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See detailLe modèle "Barbus" (poisson cyprinidé). Un maillon indispensable dans la recherche sur les poissons d'eau douce.
Poncin, Pascal ULg; Berrebi, Patrick; Philippart, Jean_Claude et al

in Cahiers d'Ethologie Appliquée (1993), 13(2), 129-130

Detailed reference viewed: 51 (3 ULg)
See detailModèle 3-D de dispersion atmosphérique de radioéléments autour du site de Tihange
Bourouag, Mohamed ULg; Dzisiak, J. P.; Everbecq, Etienne ULg

Report (1993)

Le rapport reprend la description du modèle de dispersion et de déposition des radioéléments rejetés aux cheminées de Tihange réalisé par l'ULG, dans le but d'aboutir in fine à un logiciel permettant d ... [more ▼]

Le rapport reprend la description du modèle de dispersion et de déposition des radioéléments rejetés aux cheminées de Tihange réalisé par l'ULG, dans le but d'aboutir in fine à un logiciel permettant d'évaluer en temps réel les conséquences radiologiques des rejets de routine ou accidentels de la centrale. [less ▲]

Detailed reference viewed: 21 (3 ULg)