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See detailAutomatic grading of Bi-colored apples by multispectral machine vision
Unay, Devrim; Gosselin, Bernard; Kleynen, Olivier et al

in Computers & Electronics in Agriculture (2011)

In this paper we present a novel application work for grading of apple fruits by machine vision. Following precise segmentation of defects by minimal confusion with stem/calyx areas on multispectral ... [more ▼]

In this paper we present a novel application work for grading of apple fruits by machine vision. Following precise segmentation of defects by minimal confusion with stem/calyx areas on multispectral images, statistical, textural and geometric features are extracted from the segmented area. Using these features, statistical and syntactical classifiers are trained for two- and multi-category grading of the fruits. Results showed that feature selection provided improved performance by retaining only the important features, and statistical classifiers outperformed their syntactical counterparts. Compared to the state-of-the-art, our two-category grading solution achieved better recognition rates (93.5% overall accuracy). In this work we further provided a more realistic multi-category grading solution, where different classification architectures are evaluated. Our observations showed that the single-classifier architecture is computationally less demanding, while the cascaded one is more accurate. [less ▲]

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See detailAutomatic learning for the classification of primary frequency control behaviour
Cornélusse, Bertrand ULg; Wehenkel, Louis ULg; Wera, Claude

in Power Tech, 2007 IEEE Lausanne (2007)

In this paper we propose a methodology based on supervised automatic learning in order to classify the behaviour of generators in terms of their performance in providing primary frequency control ... [more ▼]

In this paper we propose a methodology based on supervised automatic learning in order to classify the behaviour of generators in terms of their performance in providing primary frequency control ancillary services. The problem is posed as a time-series classification problem, and handled by using state-of- the-art supervised learning methods such as ensembles of decision trees and support-vector machines combined with several preprocessing techniques. The method was designed in the context of the Belgian system and is validated on real-life data composed of more than 600 time-series recorded on this system. [less ▲]

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See detailAutomatic learning of sequential decision strategies for dynamic security assessment and control
Wehenkel, Louis ULg; Glavic, Mevludin; Geurts, Pierre ULg et al

in Proceedings of the IEEE Power Engineering Society General Meeting 2006 (2006)

This paper proposes to formulate security control as a sequential decision making problem and presents new developments in automatic learning of sequential decision making strategies from simulations and ... [more ▼]

This paper proposes to formulate security control as a sequential decision making problem and presents new developments in automatic learning of sequential decision making strategies from simulations and/or information collected from real-life system measurements. The exploitation of these methods for the design of decision making strategies and control policies in the context of preventive and emergency mode dynamic security assessment and control is discussed and further opportunities for research in this area are highlighted. [less ▲]

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See detailAutomatic learning techniques in power systems
Wehenkel, Louis ULg

Book published by Springer (1997)

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See detailAutomatic localization of interest points in zebrafish images with tree-based methods
Stern, Olivier ULg; Marée, Raphaël ULg; Aceto, Jessica ULg et al

in Proceedings of the 6th IAPR International Conference on Pattern Recognition in Bioinformatics (2011)

In many biological studies, scientists assess effects of experimental conditions by visual inspection of microscopy images. They are able to observe whether a protein is expressed or not, if cells are ... [more ▼]

In many biological studies, scientists assess effects of experimental conditions by visual inspection of microscopy images. They are able to observe whether a protein is expressed or not, if cells are going through normal cell cycles, how organisms evolve in different experimental conditions, etc. But, with the large number of images acquired in high-throughput experiments, this manual inspection becomes lengthy, tedious and error-prone. In this paper, we propose to automatically detect specific interest points in microscopy images using machine learning methods with the aim of performing automatic morphometric measurements in the context of Zebrafish studies. We systematically evaluate variants of ensembles of classification and regression trees on four datasets corresponding to different imaging modalities and experimental conditions. Our results show that all variants are effective, with a slight advantage for multiple output methods, which are more robust to parameter choices. [less ▲]

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See detailAutomatic multiclass classification of 18FDG-PET scans for the distinction between Parkinson’s disease and atypical parkinsonian syndromes
Phillips, Christophe ULg; Schrouff, Jessica ULg; Luxen, André ULg et al

Poster (2012, June 10)

Part of the difficulty in the early diagnosis of Parkinson’s disease (PD) is in differentiating it from atypical parkinsonian disorders (APS) that have a poorer prognosis such as multiple system atrophy ... [more ▼]

Part of the difficulty in the early diagnosis of Parkinson’s disease (PD) is in differentiating it from atypical parkinsonian disorders (APS) that have a poorer prognosis such as multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS). 18flurodeoxyglucose (FDG) positron emission tomography (PET) has been recommended for the early differentiation between PD and APS [1]. Here, 120 FDG PET scans (42, 31, 26 and 21 for the PD, MSA, PSP and CBS resp.) were acquired on average 3.5 years after symptoms onset (because the initial clinical features were outside the prevailing perception for PD) to look, without any a priori assumption, for cerebral FDG uptake patterns that discriminate either between the PD and APS classes, or between the four PD, MSA, PSP and CBS classes. The diagnostic used to label the scans was defined by clinical criteria on average 4.5 years after PET assessment. [less ▲]

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See detailAutomatic Object Recognition from Range Imagery Using Appearance Models
Verly, Jacques ULg; Williams, Brian D.; Dudgeon, Dan E.

Conference (1987, December)

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See detailAutomatic Photometric Telescopes and Photometric Accuracy
Sterken, C.; Manfroid, Jean ULg

in Precision Photometry: Astrophysics of the Galaxy (1991)

Not Available

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See detailAutomatic Photometry at La Silla
Sterken, C.; Manfroid, Jean ULg

in The Messenger (1991), 63

Not Available

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See detailAutomatic plastic-hinge analysis and design of 3D steel frames
Hoang, Van Long ULg

Book published by University of Liege (2008)

Detailed reference viewed: 85 (28 ULg)
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See detailAutomatic real-time collection of RCS of airplanes in a real bistatic low-frequency configuration using a software defined passive radar based on illuminators of opportunity
Pisane, Jonathan ULg; Azarian, Sylvain; Lesturgie, Marc et al

in Proceedings of the 2012 IEEE Radar Conference (2012, May)

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See detailAn automatic remeshing processor
Habraken, Anne ULg

in Journal of Materials Processing Technology (1990), 24

Detailed reference viewed: 7 (2 ULg)
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See detailAn automatic remeshing technique for finite element simulation of forming processes
Habraken, Anne ULg; Cescotto, Serge ULg

in International Journal for Numerical Methods in Engineering (1990), 30(8), 1503-1525

Detailed reference viewed: 43 (8 ULg)
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See detailAutomatic Scoring of sleep apnea and hypopnea by analysis of mandibular movements
Senny, Frédéric ULg; Destiné, Jacques ULg; Verly, Jacques ULg et al

in M.H.Hamza (Ed.) Proceedings of the 3rd International IASTED International conference on Biomedical Engineering (2005, February)

In this paper, we propose a method for sleep apnea and hypopnea detection by analyzing the mandibular movements recorded during sleep. This signal, highly correlated with the esophageal pressure during ... [more ▼]

In this paper, we propose a method for sleep apnea and hypopnea detection by analyzing the mandibular movements recorded during sleep. This signal, highly correlated with the esophageal pressure during apnea or hypopnea, is a good marker of respiratory efforts. The respiratory efforts and their background activity are used to detect salient mandibular movements related to sleep apnea and hypopnea, to delineate and to recognize episodes of sleep apnea and hypopnea. The method presented may be extended to others breathing disorders such as Respiratory Efforts Related Arousals (RERA). [less ▲]

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See detailAutomatic shape optimization with GAs and a 2D free surface flow solver
Erpicum, Sébastien ULg; Dewals, Benjamin ULg; Pirotton, Michel ULg

in Proceedings of the 4th International Conference on Advanced Computational Methods in Engineering (2008)

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See detailAutomatic stimulus-induced medial premotor cortex activation without perception or action
D'Ostilio, Kevin ULg; Garraux, Gaëtan ULg

Poster (2010)

Evidence from functional imaging studies suggests that well-established stimulus-action associations may induce an automatic activation of the motor preparation system even when there is no intention to ... [more ▼]

Evidence from functional imaging studies suggests that well-established stimulus-action associations may induce an automatic activation of the motor preparation system even when there is no intention to make the associated movement (Grezes & Decety, 2002). Here we investigated whether this automatic motor activation can also be elicited by visual stimuli that are not consciously perceived. However, previous subliminal masked experiments used supraliminal response-target in such a way that unconscious mechanisms were inferred from the accumulation of the effect of the subliminal masked stimulus and the motor response. Here, to investigate neural correlates of unconscious process induced by subliminal stimuli, we used event-related BOLD fMRI at 3T to record brain activity in 24 healthy volunteers (mean age: 21 ± 2 years) as they performed a subliminal priming task (see Eimer & Schlaghecken, 1998). In this visuomotor task, participants were asked to make speeded button presses with the left or right hand following double leftward (<< <<) or rightward (>> >>) pointing arrows, which were preceded by a masked subliminal prime of 17 ms (compatible/incompatible arrows or neutral stimulus). Reaction time analysis revealed the classical positive compatibility effect (PCE), mainly shorter reaction times for compatible (mean RT: 369±38 ms) than for incompatible (mean RT: 383± 30 ms) in comparison to neutral trials (mean RT: 375± 38 ms). In a prime identification task, subjects’ performance was at chance level for primes presented for 17 ms, suggesting that the prime was not consciously perceived in the main experiment. Theses behavioral results suggest an automatic and unconscious motor activation induced by the prime. The responded stimuli were randomly intermixed with non-responded stimuli (0 0) with the assumption that the subliminal arrow prime also elicited an automatic motor activation in these passive trials as in responded trials. Imaging analysis of these non-responded trials showed first that activation was mainly restricted to posterior brain areas when using a subliminal stimulus that has not been previously associated with a motor response. Second, when the subliminal stimulus has been strongly associated with a motor response, this activation extended to rostral brain regions classically involved in motor preparation as the SMA, the premotor cortex and the striatum (cluster level p< 0.05 corrected). This finding corroborates the involvement of a fronto-striatal network, especially of the SMA in automatic and unconscious motor activation. [less ▲]

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See detailAutomatic Stimulus-Induced Medial Premotor Cortex Activation without Perception or Action
D'Ostilio, Kevin ULg; Garraux, Gaëtan ULg

in PLoS ONE (2011), 6(2),

Who has ever been surprised to return to the bowl of salted peanuts without realizing it, even after having eating a moderate number and deciding to stop? Using rapid event-related functional magnetic ... [more ▼]

Who has ever been surprised to return to the bowl of salted peanuts without realizing it, even after having eating a moderate number and deciding to stop? Using rapid event-related functional magnetic resonance imaging (fMRI) in healthy volunteers, we investigated the neural correlates of automatic processes induced by subliminal stimuli. We demonstrated that the automatic activation of motor programs elicited unconsciously in the medial premotor cortex was normally restricted to specific contexts set by the environment, but can occur below the threshold of awareness even when no movement was executed. This novel finding expands our view on brain mechanisms underlying unconscious motor control and provides new evidence that activation of the motor preparation system and consciousness are not obligatory linked. [less ▲]

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See detailAutomatic Synthesis of [18F]Altanserin, a Radiopharmaceutical for Positron Emission Tomographic Studies of the Serotonergic Type-2 Receptors
Monclus, Michel; Van Naemen, John; Mulleneers, Eric et al

in Clinical Positron Imaging (1998), 1(2), 111-116

[18F]Altanserin is routinely used in several centers to study the serotonergic type-2 receptors (5HT2) with positron emission tomography (PET). An automatic production system allowing the preparation of ... [more ▼]

[18F]Altanserin is routinely used in several centers to study the serotonergic type-2 receptors (5HT2) with positron emission tomography (PET). An automatic production system allowing the preparation of multimillicurie amounts [>1.5 GBq (40 mCi) EOS, mean radiochemical yield 20 ± 6% EOB, specific activity >1 Ci/µmol Image] of this radiopharmaceutical within a synthesis time of 90 minutes (quality controls included) is described in this paper. The apparatus includes the recovery of the activity from the target, the preparation of the dried [18F]KF/kryptofix 2.2.2 complex, the labeling reaction using a microwave cavity, the Sep Pak and HPLC purification. A sterile, pyrogen-free and single use unit was also developed for the formulation of the injectable solution. This last part could be used for the formulation of many other radiopharmaceuticals. [less ▲]

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See detailAutomatic Synthesis of Specifications from the Dynamic Observation of Reactive Programs
Boigelot, Bernard ULg; Godefroid, Patrice

in Lecture Notes in Computer Science (1997), 1217

VeriSoft is a tool for systematically exploring the state spaces of systems composed of several concurrent processes executing arbitrary C (or C++) code. VeriSoft can automatically detect coordination ... [more ▼]

VeriSoft is a tool for systematically exploring the state spaces of systems composed of several concurrent processes executing arbitrary C (or C++) code. VeriSoft can automatically detect coordination problems between the concurrent processes of a system. In this paper, we present a method to synthesize a finite-state machine that simulates all the sequences of visible operations of a given process that were observed during a state-space exploration performed by VeriSoft. The examination of this machine makes it possible to discover the dynamic behavior of the process in its environment and to understand how it contributes to the global behavior of the system. [less ▲]

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