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See detailA Decision Problem for Ultimately Periodic Sets in Non-standard Numeration Systems
Bell, Jason; Charlier, Emilie ULg; Fraenkel, Aviezri et al

in International Journal of Algebra & Computation (2009), 19

Consider a non-standard numeration system like the one built over the Fibonacci sequence where nonnegative integers are represented by words over {0,1} without two consecutive 1. Given a set X of integers ... [more ▼]

Consider a non-standard numeration system like the one built over the Fibonacci sequence where nonnegative integers are represented by words over {0,1} without two consecutive 1. Given a set X of integers such that the language of their greedy representations in this system is accepted by a finite automaton, we consider the problem of deciding whether or not X is a finite union of arithmetic progressions. We obtain a decision procedure for this problem, under some hypothesis about the considered numeration system. In a second part, we obtain an analogous decision result for a particular class of abstract numeration systems built on an infinite regular language. [less ▲]

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See detailA Decision Problem for Ultimately Periodic Sets in Non-standard Numeration Systems
Charlier, Emilie ULg; Rigo, Michel ULg

in Lecture Notes in Computer Science (2008), 5162

Consider a non-standard numeration system like the one built over the Fibonacci sequence where nonnegative integers are represented by words over {0, 1} without two consecutive 1. Given a set X of ... [more ▼]

Consider a non-standard numeration system like the one built over the Fibonacci sequence where nonnegative integers are represented by words over {0, 1} without two consecutive 1. Given a set X of integers such that the language of their greedy representations in this system is accepted by a finite automaton, we consider the problem of deciding whether or not X is a finite union of arithmetic progressions. We obtain a decision procedure under some hypothesis about the considered numeration system. In a second part, we obtain an analogous decision result for a particular class of abstract numeration systems built on an infinite regular language. [less ▲]

Detailed reference viewed: 27 (13 ULg)
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See detailDecision processes in perspectives of a drought network
Cornélis, Bernard; Viau, Alain; Donnay, Jean-Paul ULg

in Exploratory Workshop on Drought and Drought Mitigation in Europe (1999)

Detailed reference viewed: 7 (1 ULg)
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See detailDecision Support for Improving Public Transport Network
Vanraes, Nico; Cornélis, Bernard; Donnay, Jean-Paul ULg

in Proceedings of the 4th Design and Decision Support Systems in Architecture and Urban Planning (1998)

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See detailA Decision Support System To Simulate And Compare Silvicultural Scenarios For Pure Even-Aged Larch Stands
Pauwels, D.; Lejeune, Philippe ULg; Rondeux, Jacques ULg

in Annals of Forest Science : a Multidisciplinary and International Journal (2007), 64(3), 345-353

In sustained forest management, it is particularly useful to test the adequacy of various silvicultural scenarios, but decision-making is also becoming increasingly complex because forest managers have to ... [more ▼]

In sustained forest management, it is particularly useful to test the adequacy of various silvicultural scenarios, but decision-making is also becoming increasingly complex because forest managers have to simultaneously meet several different objectives in response to society demands. In order to help forest managers make appropriate choices in silvicultural systems, we propose a SDSS (Silvicultural Decision Support System) that applies to pure and even-aged larch stands (Larix sp.) in lowland areas where site conditions are similar to those encountered in Southern Belgium. Its main purpose is (i) to predict the influence of silvicultural treatments on stand evolution and (ii) assist forest managers in comparing different scenarios with respect to predefined goals. This SDSS consists in three modules designed to elaborate silvicultural scenarios involving (i) stand growth prediction and thinning simulation; (ii) assessment of indicators selected to define the scenarios referring to wood production, financial, technico-economic and ecological components, tree stability and wood quality; and (iii) comparison of the scenarios on the basis of the set of previously assessed indicators (multi-criteria analysis). User-friendly “MGC_Larch” software helps managers to formulate, evaluate and compare different silvicultural scenarios for larch. [less ▲]

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See detailDecision support tools for clinical diagnosis of disease in cows with suspected bovine spongiform encephalopathy.
Saegerman, Claude ULg; Speybroeck, N.; Roels, S. et al

in Journal of Clinical Microbiology (2004), 42(1), 172-8

Reporting of clinically suspected cattle is currently the most common method for detecting cases of bovine spongiform encephalopathy (BSE). Improvement of clinical diagnosis and decision-making remains ... [more ▼]

Reporting of clinically suspected cattle is currently the most common method for detecting cases of bovine spongiform encephalopathy (BSE). Improvement of clinical diagnosis and decision-making remains crucial. A comparison of clinical patterns, consisting of 25 signs, was made between all 30 BSE cases, confirmed in Belgium before October 2002, and 272 suspected cases that were subsequently determined to be histologically, immunohistochemically, and scrapie-associated-fiber negative. Seasonality in reporting suspected cases was observed, with more cases being reported during wintertime when animals were kept indoors. The median duration of illness was 30 days. The 10 most relevant signs of BSE were kicking in the milking parlor, hypersensitivity to touch and/or sound, head shyness, panic-stricken response, reluctance to enter in the milking parlor, abnormal ear movement or carriage, increased alertness behavior, reduced milk yield, teeth grinding, and temperament change. Ataxia did not appear to be a specific sign of BSE. A classification and regression tree was constructed by using the following four features: age of the animal, year of birth, number of relevant BSE signs noted, and number of clinical signs, typical for listeriosis, noted. The model had a sensitivity of 100% and a specificity of 85%. This approach allows the use of an interactive decision-support tool, based entirely on odds ratios, a statistic independent of disease prevalence. [less ▲]

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See detailDecision theory applied to bad data identification in power system state estimation
Mili, Lamine; Van Cutsem, Thierry ULg; Ribbens-Pavella, Mania

in Proc. 7th IFAC Symp. on Identification and system Parameter Estimation (1985)

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See detailDecision theory for fault diagnosis in electric power systems
Mili, Lamine; Van Cutsem, Thierry ULg; Pavella, Mania

in Automatica (1987), 23

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See detailDecision tree algorithm for detection of spatial processes in landscape transformation.
Bogaert, Jan ULg; Ceulemans, R; Salvador-Van Eysenrode, D

in Environmental Management (2004), 33(1), 62-73

Detailed reference viewed: 38 (3 ULg)
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See detailDecision tree approach to power systems security assessment
Wehenkel, Louis ULg; Pavella, Mania ULg

in International Journal of Electric Power and Energy Systems (1993), 15(1), 13-36

An overview of the general decision tree approach to power system security assessment is presented. The general decision tree methodology is outlined, modifications proposed in the context of transient ... [more ▼]

An overview of the general decision tree approach to power system security assessment is presented. The general decision tree methodology is outlined, modifications proposed in the context of transient stability assessment are embedded, and further refinements are considered. The approach is then suitably tailored to handle other specifics of power systems security, relating to both preventive and emergency voltage control, in addition to transient stability. Trees are accordingly built in these various application domains, and their salient features are explored, assessed, compared. Among attractive aspects of the trees, we mention their ability to uncover the intrinsic mechanism governing physical processes, and to provide a clear description in terms of tractable system parameters. Further, their dual, 'attribute space' representation is shown to have complementary possibilities for more refined analysis and, in addition, for sensitivity assessment and control. Overall, the approach is characterized by its great flexibility with respect to tree structure, types of physical parameters driving the phenomena, and classes of potential applications. To illustrate and support the developments,real-world examples are reported, rolatin 9 to transient and voltage stability issues simulated on several power systems. [less ▲]

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See detailDecision tree approaches to voltage security assessment
Van Cutsem, Thierry ULg; Wehenkel, Louis ULg; Pavella, Mania ULg et al

in IEE Proceedings - Generation, Transmission & Distribution (1993), 140

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See detailDecision tree pruning using an additive information quality measure
Wehenkel, Louis ULg

in Bouchon-Meunier, B; Valverde, L; Yager, R (Eds.) Uncertainty in Intelligent Systems (1993)

An additive quality measure based on information theory is introduced for the inductive inference of decision trees. It takes into account both the information content and the complexity of a tree ... [more ▼]

An additive quality measure based on information theory is introduced for the inductive inference of decision trees. It takes into account both the information content and the complexity of a tree, combined so as to evaluate the tree on the basis of its learning sample. The additivity of the quality measure with respect to the decomposition of a tree into subtrees, allows to formulate an efficient recursive backward pruning algorithm to maximize the quality. Simulation results are provided on the ground of a real life problem related to electric power system operation and a synthetic digit recognition problem. [less ▲]

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See detailDecision Trees and Random Subwindows for Object Recognition
Marée, Raphaël ULg; Geurts, Pierre ULg; Piater, Justus ULg et al

in ICML workshop on Machine Learning Techniques for Processing Multimedia Content (MLMM2005) (2005)

In this paper, we compare five tree-based machine learning methods within a recent generic image classification framework based on random extraction and classification of subwindows. We evaluate them on ... [more ▼]

In this paper, we compare five tree-based machine learning methods within a recent generic image classification framework based on random extraction and classification of subwindows. We evaluate them on three publicly available object recognition datasets (COIL-100, ETH-80, and ZuBuD). Our comparison shows that this general and conceptually simple framework yields good results when combined with ensemble of decision trees, especially when using Tree Boosting or Extra-Trees. The latter is also particularly attractive in terms of computational efficiency. [less ▲]

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See detailDecision Trees and Transient Stability of Electric Power Systems
Wehenkel, Louis ULg; Pavella, Mania ULg

in Automatica (1991), 27(1), 115-134

An inductive inference method for the automatic building of decision trees is investigated. Among its various tasks, the splitting and the stop splitting criteria successively applied to the nodes of a ... [more ▼]

An inductive inference method for the automatic building of decision trees is investigated. Among its various tasks, the splitting and the stop splitting criteria successively applied to the nodes of a grown tree, are found to play a crucial role on its overall shape and performances. The application of this general method to transient stability is systematically explored. Parameters related to the stop splitting criterion, to the learning set and to the tree classes are thus considered, and their influence on the tree features is scrutinized. Evaluation criteria appropriate to assess accuracy are also compared. Various tradeoffs are further examined, such as complexity vs number of classes, or misclassification rate vs type of misclassification errors. Possible uses of the trees are also envisaged. Computational issues relating to the building and the use of trees are finally discussed. [less ▲]

Detailed reference viewed: 53 (2 ULg)
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See detailDecision trees applied to on-line transient stability assessment of power systems
Wehenkel, Louis ULg; Van Cutsem, Thierry ULg; Pavella, Mania ULg

in Proc. Int. Symp. on Circuits and Systems (1988)

Detailed reference viewed: 20 (0 ULg)
See detailDecision trees for detecting emergency voltage conditions
Van Cutsem, Thierry ULg; Wehenkel, Louis ULg; Pavella, Mania ULg et al

in Proc. 2nd Intern. workshop on Bulk power system voltage phenomena : voltage stability and security (1991, August)

Detailed reference viewed: 25 (0 ULg)
See detailA decision-maker point of view on uncertainties in spatial decisions
Cornélis, Bernard ULg; Brunet, Sébastien ULg

in Goodchild, Michael; Fisher, Peter; Shi, Wenzhong (Eds.) Spatial Data Quality (2002)

Detailed reference viewed: 30 (3 ULg)