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See detailAutomata-Based Symbolic Representations of Polyhedra
Boigelot, Bernard ULg; Brusten, Julien ULg; Degbomont, Jean-François ULg

in Lecture Notes in Computer Science (2012, March), 7183

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See detailAn Automata-Theoretic Approach to Automatic Program Verification
Vardi, Moshe Y; Wolper, Pierre ULg

in Proceedings of the First Symposium on Logic in Computer Science (1986)

We describe an automata-theoretic approach to the automatic verification of concurrent finite-state programs by model checking.The basic idea underlying this approach is that for any temporal formula we ... [more ▼]

We describe an automata-theoretic approach to the automatic verification of concurrent finite-state programs by model checking.The basic idea underlying this approach is that for any temporal formula we can construct an automaton that accepts precisely the computations that satisfy the formula. The model-checking algorithm that results from this approach is much simpler and cleaner than tableau-based algorithms. We use this approach to extend model checking to probabilistic concurrent finite-state programs. concurrent finite-state programs. [less ▲]

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See detailAn Automata-Theoretic Approach to Branching-Time Model Checking
Bernholtz, Orna; Vardi, Moshe Y; Wolper, Pierre ULg

in Computer Aided Verification, Proc. 6th Int. Workshop (1994)

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See detailAn automata-theoretic approach to branching-time model checking
Kupferman, Orna; Vardi, Moshe Y; Wolper, Pierre ULg

in Journal of the ACM (2000), 47(2), 312-360

Translating linear temporal logic formulas to automata has proven to be an effective approach for implementing linear-time model-checking, and for obtaining many extensions and improvements to this ... [more ▼]

Translating linear temporal logic formulas to automata has proven to be an effective approach for implementing linear-time model-checking, and for obtaining many extensions and improvements to this verification method. On the other hand, for branching temporal logic, automate-theoretic techniques have long been thought to introduce an exponential penalty, making them essentially useless for model-checking. Recently, Bernholtz and Grumberg [1993] have shown that this exponential penalty can be avoided, though they did not match the linear complexity of non-automata-theoretic algorithms. In this paper, we show that alternating tree automata are the key to a comprehensive automata-theoretic framework for branching temporal logics. Not only can they be used to obtain optimal decision procedures, as was shown by Muller ct al., but, as we show here, they also make it possible to derive optimal model-checking algorithms. Moreover, the simple combinatorial structure that emerges from the automata-theoretic approach opens up new possibilities for the implementation of branching-time model checking, and has enabled us to derive improved space complexity bounds for this long-standing problem. [less ▲]

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See detailAn Automata-Theoretic Approach to Presburger Arithmetic Constraints
Wolper, Pierre ULg; Boigelot, Bernard ULg

in Lecture Notes in Computer Science (1995), 983

This paper introduces a finite-automata based representation of Presburger arithmetic definable sets of integer vectors. The representation consists of concurrent automata operating on the binary ... [more ▼]

This paper introduces a finite-automata based representation of Presburger arithmetic definable sets of integer vectors. The representation consists of concurrent automata operating on the binary encodings of the elements of the represented sets. This representation has several advantages. First, being automata-based it is operational in nature and hence leads directly to algorithms, for instance all usual operations on sets of integer vectors translate naturally to operations on automata. Second, the use of concurrent automata makes it compact. Third, it is insensitive to the representation size of integers. Our representation can be used whenever arithmetic constraints are needed. To illustrate its possibilities we show that it can handle integer programming optimally, and that it leads to a new original algorithm for the satisfiability of arithmetic inequalities. [less ▲]

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See detailL'automate spirituel : pensée et cinéma chez Walter Benjamin
Barbion, Sébastien ULg

Conference (2013, April 24)

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See detailAutomated analysis of background EEG and reactivity during therapeutic hypothermia in comatose patients after cardiac arrest
Noirhomme, Quentin ULg; Lehembre, Rémy; Lugo, Zulay et al

in Clinical EEG and Neuroscience : Official Journal of the EEG and Clinical Neuroscience Society (ENCS) (2014)

Visual analysis of electroencephalography (EEG) background and reactivity during therapeutic hypothermia provides important outcome information, but is time-consuming and not always consistent between ... [more ▼]

Visual analysis of electroencephalography (EEG) background and reactivity during therapeutic hypothermia provides important outcome information, but is time-consuming and not always consistent between reviewers. Automated EEG analysis may help quantify the brain damage. Forty-six comatose patients in therapeutic hypothermia, after cardiac arrest, were included in the study. EEG background was quantified with burst-suppression ratio (BSR) and approximate entropy, both used to monitor anesthesia. Reactivity was detected through change in the power spectrum of signal before and after stimulation. Automatic results obtained almost perfect agreement (discontinuity) to substantial agreement (background reactivity) with a visual score from EEG-certified neurologists. Burst-suppression ratio was more suited to distinguish continuous EEG background from burst-suppression than approximate entropy in this specific population. Automatic EEG background and reactivity measures were significantly related to good and poor outcome. We conclude that quantitative EEG measurements can provide promising information regarding current state of the patient and clinical outcome, but further work is needed before routine application in a clinical setting. [less ▲]

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See detailAutomated analysis of enzyme inactivation phenomena. Application to beta-lactamases and DD-peptidases.
De Meester, Fabien; Joris, Bernard ULg; Reckinger, Georges et al

in Biochemical Pharmacology (1987), 36

In the presence of a reporter substrate, the progressive inactivation of an enzyme was easily studied by directly transmitting absorbance readings to a microcomputer. Pseudo-first order rate constants as ... [more ▼]

In the presence of a reporter substrate, the progressive inactivation of an enzyme was easily studied by directly transmitting absorbance readings to a microcomputer. Pseudo-first order rate constants as high as 0.3 sec-1 were rapidly and accurately measured. When utilization of the reporter substrate did not exceed 10%, the rate of the reaction (vt) could be considered as proportional to the active enzyme concentration at any time during the analysis and the decrease of vt was first order with time. This simple method was used to follow the inactivation of beta-lactamases (EC 3.5.2.6) by various physical and chemical agents. When a large proportion (30-80%) of reporter substrate was destroyed, a correction was introduced to account for the corresponding decrease of its rate of utilization. This enabled experiments to be performed with a DD-peptidase and a substrate exhibiting a low delta epsilon upon hydrolysis. For the first time, the inactivation of a penicillin-sensitive enzyme by a beta-lactam could be continuously and directly observed. Finally, the method was extended to the study of hysteresis phenomena. [less ▲]

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See detailAutomated characterisation of intergrowth textures in mineral particles. A case study
Perez-Barnuevo, Laura; Pirard, Eric ULg; Castroviejo, Ricardo

in Minerals Engineering (2013)

The characterisation of mineral texture has been a major concern for process mineralogists, as liberation characteristics of the ores are intimately related to the mineralogical texture. While a great ... [more ▼]

The characterisation of mineral texture has been a major concern for process mineralogists, as liberation characteristics of the ores are intimately related to the mineralogical texture. While a great effort has been done to automatically characterise texture in unbroken ores, the characterisation of textural attributes in mineral particles is usually descriptive. However, the quantitative characterisation of texture in mineral particles is essential to improve and predict the performance of minerallurgical processes (i.e. all the processes involved in the liberation and separation of the mineral of interest) and to achieve a more accurate geometallurgical model. Driven by this necessity of achieving a more complete characterisation of textural attributes in mineral particles, a methodology has been recently developed to automatically characterise the type of intergrowth between mineral phases within particles by means of digital image analysis. In this methodology, a set of minerallurgical indices has been developed to quantify different mineralogical features and to identify the intergrowth pattern by discriminant analysis. The paper shows the application of the methodology to the textural characterisation of chalcopyrite in the rougher concentrate of the Kansanshi copper mine (Zambia). In this sample, the variety of intergrowth patterns of chalcopyrite with the other minerals has been used to illustrate the methodology. The results obtained show that the method identifies the intergrowth type and provides quantitative information to achieve a complete and detailed mineralogical characterisation. Therefore, the use of this methodology as a routinely tool in automated mineralogy would contribute to a better understanding of the ore behaviour during liberation and separation processes. [less ▲]

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See detailAutomated Defect Detection Algorithm Applied to Shearography in Composites
Vandenrijt, Jean-François ULg; Georges, Marc ULg

in Osten, Wolfgang (Ed.) Fringe 2013 (2014)

The aeronautic industry is progressively introducing composite material in its products. Nowadays the fabrication begins to be mature, but huge efforts remains to be done on the experimental validation of ... [more ▼]

The aeronautic industry is progressively introducing composite material in its products. Nowadays the fabrication begins to be mature, but huge efforts remains to be done on the experimental validation of these materials. More specifically, these composite materials introduce new type of defects (such as delamination, glue defects…) which need to be detected during the fabrication and maintenance to prevent failures. Moreover, the widespread use of these materials impose to the future detection instruments to be cheap, robust and easy to manipulate by non-specialists. Currently shearography is widely used for the detection of defects in the composite material. It is cheap, and relatively robust and flexible, but requires special qualification to interpret the shearograms and identify the defects. Therefore, efforts need to be carried to ease the interpretation of stereographic results for non-specialist of the technique. For this, we propose to automate the identification of defects in shearograms by the development of specific algorithms. In this paper, we present an innovative algorithm which realizes this operation. The process inspects the wrapped phase map obtained to identify high local fringe density. These potential detects are then analyzed and selected based on a set of parameter criteria such as dimensions, shape, and detection threshold. Successful results obtained on thermally solicited composite sample observed in industrial conditions are shown. We also discuss the limitations and perspective of this approach. [less ▲]

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See detailAutomated determination of acyclovir in human plasma using solid phase extraction and liquid chromatography
Chiap, Patrice ULg; Planck, I.; Evrard, Brigitte ULg et al

in Journal de Pharmacie de Belgique (1998), 53

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See detailAutomated determination of camazepam in human plasma by solid phase extraction coupled to HPLC
Hubert, Philippe ULg; Chiap, Patrice ULg; Ceccato, Attilio ULg et al

in Journal de Pharmacie de Belgique (1995), 50

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See detailAutomated determination of drugs in ibological fluids using solid-phase extraction coupled to HPLC
Hubert, Philippe ULg

in Dissertation abstracts international (1995)

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See detailAutomated determination of pirlindole enantiomers in plasma by on-line coupling of a pre-column packed with restricted access material to a chiral liquid chromatographic column
Chiap, Patrice ULg; Ceccato, Attilio ULg; Gora, R. et al

in Journal of Pharmaceutical & Biomedical Analysis (2002), 27(3-4), 447-455

A fully automated liquid chromatographic method has been developed for the determination of the enantiomers of pirlindole, an antidepressant drug, in human plasma. The method is based on the use of a pre ... [more ▼]

A fully automated liquid chromatographic method has been developed for the determination of the enantiomers of pirlindole, an antidepressant drug, in human plasma. The method is based on the use of a pre-column packed with restricted access material (RAM) (LiChrospher ADS RP-4) for sample clean-up coupled to a column containing a cellulose tris-(3,5-dimethylphenylcarbamate) based chiral stationary phase (Chiralcel OD-R) for the separation and quantitative analysis of pirlindole enantiomers. A 50-microl plasma volume was injected directly onto the pre-column using a mixture of phosphate buffer (pH 5.0) and methanol (97:3; v/v) as washing liquid. By rotation of a switching valve, the analytes were then eluted in the back-flush mode with the LC mobile phase. A complete separation of pirlindole enantiomers was obtained in 22 min on the Chiralcel OD-R column, using a mobile phase made of a mixture of phosphate buffer (pH 5.0) containing 50 mM sodium perchlorate and acetonitrile (65:35; v/v). The flow-rate was 0.6 ml/min and the analytes were detected fluorometrically using 295 and 340 nm as excitation and emission wavelengths, respectively. The method was then validated and was found to be linear in the 2.5-200 ng/ml range. The limit of detection was lower than 1 ng/ml. Repeatability and intermediate precision at a concentration of 50 ng/ml were about 1.5 and 3.5%, respectively. [less ▲]

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See detailAutomated determination of sulfadimidine in ovine plasma by solid phase extraction and HPLC
Hubert, Philippe ULg; Evrard, Brigitte ULg; Delattre, Luc ULg et al

in Journal de Pharmacie de Belgique (1992), 47

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See detailAutomated Determination of Tramadol Enantiomers in Human Plasma Using Solid-Phase Extraction in Combination with Chiral Liquid Chromatography
Ceccato, Attilio ULg; Chiap, Patrice ULg; Hubert, Philippe ULg et al

in Journal of Chromatography. B : Biomedical Sciences and Applications (1997), 698(1-2), 161-70

A sensitive and automated method for the separation and individual determination of tramadol enantiomers in plasma has been developed using solid-phase extraction (SPE) on disposable extraction cartridges ... [more ▼]

A sensitive and automated method for the separation and individual determination of tramadol enantiomers in plasma has been developed using solid-phase extraction (SPE) on disposable extraction cartridges (DECs) in combination with chiral liquid chromatography (LC). The SPE operations were performed automatically by means of a sample processor equipped with a robotic arm (ASPEC system). The DEC filled with ethyl silica (50 mg) was first conditioned with methanol and phosphate buffer, pH 7.4. A 1.0-ml volume of plasma was then applied on the DEC. The washing step was performed with the same buffer. The analytes were eluted with 0.15 ml of methanol, and 0.35 ml of phosphate buffer, pH 6.0, containing sodium perchlorate (0.2 M) were added to the extract before injection into the LC system. The enantiomeric separation of tramadol was achieved using a Chiralcel OD-R column containing cellulose tris-(3,5-dimethylphenylcarbamate) as chiral stationary phase. The mobile phase was a mixture of phosphate buffer, pH 6.0, containing sodium perchlorate (0.2 M) and acetonitrile (75:25). The mobile-phase pH and the NaClO4 concentration were optimized with respect to enantiomeric resolution. The method developed was validated. Recoveries for both enantiomers of tramadol were about 100%. The method was found to be linear in the 2.5-150 ng/ml concentration range [r2=0.999 for (+)- and (-)-tramadol]. The repeatability and intermediate precision at a concentration of 50 ng/ml were 6.5 and 8.7% for (+)-tramadol and 6.1 and 7.6% for (-)-tramadol, respectively. [less ▲]

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