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See detailNon-homogeneous Beatty sequences leading to invariant games
Cassaigne, Julien; Duchêne, Eric; Rigo, Michel ULg

in SIAM Journal on Discrete Mathematics (in press)

We characterize pairs of complementary non-homogeneous Beatty sequences $(A_n)_{n>0}$ and $(B_n)_{n>0}$, with the restriction $A_1=1$ and $B_1\geq 3$, for which there exists an invariant take-away game ... [more ▼]

We characterize pairs of complementary non-homogeneous Beatty sequences $(A_n)_{n>0}$ and $(B_n)_{n>0}$, with the restriction $A_1=1$ and $B_1\geq 3$, for which there exists an invariant take-away game having $\{(A_n,B_n),(B_n,A_n)\mid n> 0\}\cup\{(0,0)\}$ as set of $P$-positions. Using the notion of Sturmian word arising in combinatorics on words, this characterization can be translated into a decision procedure relying only on a few algebraic tests about algebraicity or rational independence. This work partially answers to a question of Larsson et al. raised in Larsson et al. [less ▲]

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See detailOptimized approach to retrieve information on atmospheric carbonyl sulfide (OCS) above the Jungfraujoch station and change in its abundance since 1995
Lejeune, Bernard ULg; Mahieu, Emmanuel ULg; Vollmer, M. K. et al

in Journal of Quantitative Spectroscopy & Radiative Transfer (in press)

In this paper, we present an optimized retrieval strategy for carbonyl sulfide (OCS), using Fourier transform infrared (FTIR) solar observations made at the high-altitude Jungfraujoch station in the Swiss ... [more ▼]

In this paper, we present an optimized retrieval strategy for carbonyl sulfide (OCS), using Fourier transform infrared (FTIR) solar observations made at the high-altitude Jungfraujoch station in the Swiss Alps. More than 200 lines of the nu3 fundamental band of OCS have been systematically evaluated and we selected 4 microwindows on the basis of objective criteria minimizing the effect of interferences, mainly by solar features, carbon dioxide and water vapor absorption lines, while maximizing the information content. Implementation of this new retrieval strategy provided an extended time series of the OCS abundance spanning the 1995-2015 time period, for the study of the long-term trend and seasonal variation of OCS in the free troposphere and stratosphere. Three distinct periods characterize the evolution of the tropospheric partial columns: a first decreasing period (1995-2002), an intermediate increasing period (2002-2008), and the more recent period (2008-2015) which shows no significant trend. Our FTIR tropospheric and stratospheric time series are compared with new in situ gas chromatography mass spectrometry (GCMS) measurements performed by Empa (Laboratory for Air Pollution/Environmental Technology) at the Jungfraujoch since 2008, and with space-borne solar occultation observations by the ACE-FTS instrument on-board the SCISAT satellite, respectively, and they show good agreement. The OCS signal recorded above Jungfraujoch appears to be closely related to anthropogenic sulfur emissions. [less ▲]

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See detailExperimental and Numerical Study of Mini-UAV Propeller Performance in Oblique Flow
Theys, Bart; Dimitriadis, Grigorios ULg; Hendrick, Patrick et al

in Journal of Aircraft (in press)

This paper presents the modelling of the performance of small propellers used for Vertical Take Off and Landing Micro Aerial Vehicles (VTOL MAVs) operating at low Reynolds numbers and in oblique flow ... [more ▼]

This paper presents the modelling of the performance of small propellers used for Vertical Take Off and Landing Micro Aerial Vehicles (VTOL MAVs) operating at low Reynolds numbers and in oblique flow. Blade Element Momentum Theory (BEMT), Vortex Lattice Method (VLM) and momentum theory for oblique flow are used to predict propeller performance. For validation, the predictions for a commonly used propeller for VTOL MAVs are compared to a set of wind tunnel experiments. Both BEMT and VLM succeed in predicting correct trends of the forces and moments acting upon the propeller shaft, although accuracy decreases significantly in oblique flow. For the dataset analysed here, combining the available data of the propeller in purely axial flow with momentum theory for oblique flow and applying a correction factor for the wake skew angle results in more accurate performance estimates at all elevation angles. [less ▲]

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See detailLes troubles du sommeil chez l'enfant autiste, quel rôle pour le pédopsychiatre?
Abate Ekollo, Joëlle; Malchair, Alain ULg

in Acta Psychiatrica Belgica (in press)

Les troubles du sommeil sont fréquents chez l’enfant et leurs origines sont diverses. Ces troubles ont leur ancrage dans le développement neurophysiologique et psychoaffectif de l’enfant. Les enfants ... [more ▼]

Les troubles du sommeil sont fréquents chez l’enfant et leurs origines sont diverses. Ces troubles ont leur ancrage dans le développement neurophysiologique et psychoaffectif de l’enfant. Les enfants souffrant de troubles du spectre autistique présentent un déficit de sommeil, qui peut durer jusqu’à l’adolescence. Les troubles du spectre autistique comportent des comorbidités multiples, dont des altérations du sommeil. Ils sont importants à caractériser dans cette population, car ils peuvent avoir un impact négatif sur les comportements diurnes. Par ailleurs, ils entrainent souvent des difficultés au sein de la famille. La prise en charge doit avant tout prendre en compte le contexte environnemental afin d’améliorer les habitudes et l’hygiène du sommeil. Des questionnaires ainsi que des agendas de sommeil ont été remplis par des parents afin de démontrer l’importance d’une évaluation et d’une prise en compte des troubles du sommeil chez les enfants souffrant d’autisme en consultation pédopsychiatrique. [less ▲]

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See detailEfficient ANOVA for directional data
Ley, Christophe; Swan, Yvik ULg; Verdebout, Thomas

in Annals of the Institute of Statistical Mathematics (in press)

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See detailQuadratic reformulations of nonlinear binary optimization problems
Anthony, Martin; Boros, Endre; Crama, Yves ULg et al

in Mathematical Programming (in press)

Very large nonlinear unconstrained binary optimization problems arise in a broad array of applications. Several exact or heuristic techniques have proved quite successful for solving many of these ... [more ▼]

Very large nonlinear unconstrained binary optimization problems arise in a broad array of applications. Several exact or heuristic techniques have proved quite successful for solving many of these problems when the objective function is a quadratic polynomial. However, no similarly efficient methods are available for the higher degree case. Since high degree objectives are becoming increasingly important in certain application areas, such as computer vision, various techniques have been recently developed to reduce the general case to the quadratic one, at the cost of increasing the number of variables. In this paper we initiate a systematic study of these quadratization approaches. We provide tight lower and upper bounds on the number of auxiliary variables needed in the worst-case for general objective functions, for bounded-degree functions, and for a restricted class of quadratizations. Our upper bounds are constructive, thus yielding new quadratization procedures. Finally, we completely characterize all ``minimal'' quadratizations of negative monomials. [less ▲]

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See detailConcilier la conservation des métallophytes et la phytoremédiation des sols pollués par les éléments traces métalliques
Boisson, Sylvain ULg; Ngoy Shutcha, Mylor; Mahy, Grégory ULg

in Colinet, Gilles; Mahy, Grégory; Bogaert, Jan (Eds.) Anthropisation des paysages katangais (R.D.C.) (in press)

La conservation de la biodiversité est devenue un challenge social, politique et économique au niveau mondial. Etant donné que certaines régions du monde sont fortement soumises à l’anthropisation et à ... [more ▼]

La conservation de la biodiversité est devenue un challenge social, politique et économique au niveau mondial. Etant donné que certaines régions du monde sont fortement soumises à l’anthropisation et à ses impacts, il est indispensable de modifier notre perception et notre réflexion en ce qui concerne la conservation de la biodiversité et la restauration écologique. Ce chapitre explore les possibilités existantes et les adapte pour associer la conservation des espèces végétales d’intérêt avec la phytoremédiation des sols pollués. Cette nouvelle stratégie semble encourageante pour conserver le lien entre la société et l’environnement. En utilisant la diversité végétale locale, il est possible de créer de nouvelles communautés végétales afin de réhabiliter des sols pollués par les éléments traces métalliques. Le cas de la ville de Lubumbashi et de la flore de l’Arc Cuprifère Katangais en est un exemple marquant qui a été récemment testé avec succès. Cependant, d’autres études sur les métallophytes sont essentielles pour les utiliser de manière appropriée. [less ▲]

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See detailCharles Travis, La vision est-elle intentionnelle ?
Ambroise, Bruno; Gauvry, Charlotte ULg

in Dewalque, Arnaud; Gauvry, Charlotte (Eds.) Conscience et représentation. Controverses récentes en philosophie de l'esprit (in press)

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See detailUtiliser les potentialités phénoménotechniques de la Théorie Anthropologique du Didactique : quel prix payer ?
Schneider-Gilot, Marguerite ULg

in Travaux relatifs à la Théorie Anthropologique du Didactique (Université de Toulouse) (in press)

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See detailHumnétriai… Un rite mis en images chez Philostrate
Pironti, Gabriella; Pirenne-Delforge, Vinciane ULg

in Calame, Claude; Ellinger, Pierre (Eds.) Du récit au rituel par la forme esthétique : pragmatique cultuelle des formes discursives et des images en Grèce ancienne (in press)

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See detailFrom mechanical to chemical impact of anchoring in seagrasses: the premises of anthropogenic patch generation in Posidonia oceanica meadows
Abadie, Arnaud ULg; Lejeune, Pierre; Pergent, Gérard et al

in Marine Pollution Bulletin (in press)

Intensive anchoring of leisure boats in seagrass meadows leads to mechanical damages. This anthropogenic impact creates bare mat patches that are not easily recolonized by the plant. Several tools are ... [more ▼]

Intensive anchoring of leisure boats in seagrass meadows leads to mechanical damages. This anthropogenic impact creates bare mat patches that are not easily recolonized by the plant. Several tools are used to study human impacts on the structure of seagrass meadows but they are not able to assess the indirect and long term implication of mechanical destruction. We chose to investigate the possible changes in the substrate chemistry given contrasted boat impacts. Our observations show that hydrogen sulfide concentrations remain high at 15 and 20 m depth (42.6 µM and 18.8 µM) several months after the highest period of anchoring during the summer. Moreover, our multidisciplinary study reveals that anchoring impacts of large boats at 15 and 20 m depth can potentially change the seascape structure. By taking into account both structural and chemical assessments, different managing strategies must be applied for coastal areas under anthropogenic pressures. [less ▲]

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See detailL’évaluation de la formation : comment la rendre utile pour les participants ? Constats et proposition de cinq stratégies d’évaluation partenariale
Faulx, Daniel ULg; Danse, Cédric ULg

in Evaluer : Journal International de Recherche en Education et Formation (in press)

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See detailThe workers’ speeches in the daily life scenes of the XIXth-Dynasty tombs at Deir el-Medina and its vicinity
Motte, Aurore ULg

in "Deir el-Medina and the Theban Necropolis in Contact: Describing the interactions within and outside the community of workmen" (in press)

In this paper, I study the workers’ speeches (“Reden and Rufe”) in the 19th-Dynasty tombs of Deir el-Medina and its surroundings. For this period, only three tombs in Deir el-Medina (TT 212, TT 217, and ... [more ▼]

In this paper, I study the workers’ speeches (“Reden and Rufe”) in the 19th-Dynasty tombs of Deir el-Medina and its surroundings. For this period, only three tombs in Deir el-Medina (TT 212, TT 217, and TT 266) and one in the Theban necropolis (TT 16) preserve such texts. The goal of this paper is twofold. First, it aims at showing that, after falling into disuse in elite tombs, workers’ speeches appear in the tombs of craftsmen and the upper middle class, further evidence of the “democratisation” phenomenon during the 19th Dynasty. A wall relief fragment of the craftsman Meryptah from Saqqara (18th-19th Dynasty) indicates that this phenomenon was not restricted to the Theban area. The second goal of this paper is to determine what kind of language is used in 19th-Dynasty workers’ speeches, since this literary genre is sometimes thought to be written in the vernacular. I argue that it is a mimetic language, “à-la-manière-de,” more than an actual colloquial language. Regarding this question, the tombs of Ipuy (TT 217) and Amennakht (TT 266) lead to a dead-end because of their fragmentary state. The tomb of Ramose (TT 212) and the tomb of Panehsy and his wife Tarenu (TT 16), on the other hand, reveal Late Egyptian linguistic features. But, because their owners belong to a lower social class than the elite, it might suggest a reinterpretation of the rules specific to the literary genre of the workers’speeches (possible diastratic/diaphasic variation). [less ▲]

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See detailRestaurer la Lumière. Les effets luminodynamiques de la Tour cybernétique de Nicolas Schöffer à Liège
Verbeeck, Muriel ULg; D'Haenens, Manon ULg

in Lumière et patrimoine (in press)

Cette communication porte sur la nécessaire conservation préventive de la Tour Schöffer, en amont du chantier de restauration prévu pour 2015.

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See detailMicrosyntaxe et macrosyntaxe des lexèmes _chaitif_, _dolent_, _las_ et _maleuré/maleureus_ en français médiéval. De l'adjectif au locutif
Mazziotta, Nicolas ULg

in Actes du 5e Congrès Mondial de Linguistique Française (CMLF) (in press)

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See detailLa qualité de vendeur professionnel : incidence sur la formation et l'exécution du contrat de vente d'immeuble
Kohl, Benoît ULg; Rigolet, Alexandre ULg

in La rédaction des clauses. Examen systématique et pratique (in press)

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See detailKoop op plan - Bedingen met betrekking tot de toepassing van de Wet Breyne
Kohl, Benoît ULg; Quirynen, Anneleen

in Ballon, Gabriël-Luc; De Decker, Hans; Sagaert, Vincent (Eds.) et al Koop. Onroerend Goed (in press)

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See detailL'entrepreneur
Kohl, Benoît ULg

in Guide de droit immobilier (in press)

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