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See detailLangues anciennes et analyse statistique : cinquante ans après – Distances textuelles et intertextualités
Longrée, Dominique ULg

Book published by Les études classiques (in press)

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See detailAboveground biomass mapping of African forest mosaics using canopy texture analysis: towards a regional approach.
Bastin, Jean-François ULg; Barbier, Nicolas; Couteron, Pierre et al

in Ecological Applications (in press)

In the context of the reduction of greenhouse gas emissions caused by deforestation and forest degradation (the REDD+ program), optical very high resolution (VHR) satellite images provide an opportunity ... [more ▼]

In the context of the reduction of greenhouse gas emissions caused by deforestation and forest degradation (the REDD+ program), optical very high resolution (VHR) satellite images provide an opportunity to characterize forest canopy structure and to quantify aboveground biomass (AGB) at less expense than methods based on airborne remote sensing data. Among the methods for processing these VHR images, Fourier textural ordination (FOTO) presents a good potential to detect forest canopy structural heterogeneity and therefore to predict AGB variations. Notably, the method does not saturate at intermediate AGB values as do pixelwise processing of available space borne optical and radar signals. However, a regional scale application requires to overcome two difficulties: (i) instrumental effects due to variations in sun-scene-sensor geometry or sensor-specific responses that preclude the use of wide arrays of images acquired under heterogeneous conditions and (ii) forest structural diversity including monodominant or open canopy forests, which are of particular importance in Central Africa. In this study, we demonstrate the feasibility of a rigorous regional study of canopy texture by harmonizing FOTO indices of images acquired from two different sensors (Geoeye-1 and QuickBird-2) and different sun-scene-sensor geometries and by calibrating a piecewise biomass inversion model using 26 inventory plots (1 ha) sampled across very heterogeneous forest types. A good agreement was found between observed and predicted AGB (RSE=15%; R²=0.85; p-value<0.001) across a wide range of AGB levels from 26 Mg/ha to 460 Mg/ha, and was confirmed by cross validation. A high-resolution biomass map (100 m pixels) was produced for a 400 km² area, and predictions obtained from both imagery sources were consistent with each other (r=0.86; slope=1.03; intercept=12.01 Mg/ha). These results highlight the horizontal structure of forest canopy as a powerful descriptor of the entire forest stand structure and heterogeneity. In particular, we show that quantitative metrics resulting from such textural analysis offer new opportunities to characterize the spatial and temporal variation of the structure of dense forests and may complement the toolbox used by tropical forest ecologists, managers or REDD+ national monitoring, reporting and verification bodies. [less ▲]

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See detailAtomistic account of structural and dynamical changes induced by small binders in the double helix of a short DNA
Fresch, Barbara ULg; Remacle, Françoise ULg

in Physical Chemistry Chemical Physics [=PCCP] (in press)

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See detailDe linguae latinae usu, Actes du 13e Colloque international de Linguistique latine, Bruxelles et Liège, 4-9 avril 2005
Longrée, Dominique ULg; Lenoble, Muriel; Moulart, Marie

Book published by Peeters (in press)

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See detailCarte géologique de Wallonie (Belgique) 1/10.000, 48/8 Clavier
Barchy, Laurent; Marion, Jean-Marc ULg

Cartographic material (in press)

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous edition in 1902 (at 1/40.000, by Lohest, Forir ... [more ▼]

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous edition in 1902 (at 1/40.000, by Lohest, Forir and Mourlon). [less ▲]

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See detailCarte géologique de Wallonie (Belgique) 1/10.000, 59/4 Nassogne
Barchy, Laurent; Dejonghe, Léon; Marion, Jean-Marc ULg

Cartographic material (in press)

New geological map of Wallonia published at the scale of 1/25.000 based on a new field work and using previous scientific data, produced since the previous edition published in 1900 (Stainer)

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See detailLes désignations romanes de l'ECUREUIL
Boutier, Marie-Guy ULg; Baiwir, Esther ULg

in Contini, Michel; Veny, Joan (Eds.) Atlas linguistique roman (ALiR) (in press)

L'ALiR a pour objectif de fournir une description globale du lexique roman par champ sémantique, à travers l'étude onomasiologique des désignations romanes de concepts. Les analyses lexicale, phonétique ... [more ▼]

L'ALiR a pour objectif de fournir une description globale du lexique roman par champ sémantique, à travers l'étude onomasiologique des désignations romanes de concepts. Les analyses lexicale, phonétique, morphosyntaxiques sont mises en valeur par la production de cartes interprétatives. [less ▲]

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See detailSouthern Ocean CO2 sink: The contribution of the sea ice
Delille, Bruno ULg; Vancoppenolle, M; Geilfus, N.-X. et al

in Journal of Geophysical Research. Oceans (in press)

We report first direct measurements of the partial pressure of CO2 (pCO2) within Antarctic pack sea ice brines and related CO2 fluxes across the air-ice interface. From late winter to summer, brines ... [more ▼]

We report first direct measurements of the partial pressure of CO2 (pCO2) within Antarctic pack sea ice brines and related CO2 fluxes across the air-ice interface. From late winter to summer, brines encased in the ice change from a CO2 large over-saturation, relative to the atmosphere, to a marked under-saturation while the underlying oceanic waters remains slightly oversaturated. The decrease from winter to summer of pCO2 in the brines is driven by dilution with melting ice, dissolution of carbonate minerals crystals and net primary production. As the ice warms, its permeability increases, allowing CO2 transfer at the air-sea ice interface. The sea ice changes from a transient source to a sink for atmospheric CO2. We upscale these observations to the whole Antarctic sea-icesea ice cover using the NEMO-LIM3 large-scale sea ice-ocean, and provide first estimates of spring and summer CO2 uptake from the atmosphere by Antarctic sea ice. Over the spring-summer period, the Antarctic sea-icesea ice cover is a net sink of atmospheric CO2 of 0.029 PgC, about 58% of the estimated annual uptake from the Southern Ocean. Sea ice then contributes significantly to the sink of CO2 of the Southern Ocean. [less ▲]

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See detailInsights into oxygen transport and net community production in sea ice from oxygen, nitrogen and argon concentrations
Zhou, Jiayun ULg; Delille, Bruno ULg; Brabant, F. et al

in Biogeosciences (in press)

We present the evolution of O2 standing stocks, saturation levels and concentrations in landfast sea ice, collected in Barrow (Alaska), from February to June 2009. The comparison of the standing stocks ... [more ▼]

We present the evolution of O2 standing stocks, saturation levels and concentrations in landfast sea ice, collected in Barrow (Alaska), from February to June 2009. The comparison of the standing stocks and saturation levels of O2 against those of N2 and Ar suggests that the dynamic of O2 in sea ice strongly depends on physical processes (gas incorporation and subsequent transport). We then discuss on the use of O2 / Ar and O2 / N2 to correct for the physical contribution and to determine the biological contribution (NCP) to O2 supersaturations. We conclude that O2 / Ar suits better than O2 / N2, because O2 / N2 is more sensitive due to the relative abundance of O2, N2 and Ar, and less biased when gas bubble formation and gas diffusion are maximized. We further estimate the NCP in the impermeable layers during ice growth and in the permeable layers during ice decay. Our results indicate that NCP contributed to a~release of carbon to the atmosphere in the upper ice layers, but to an uptake of carbon at sea ice bottom. Overall, seawater (rather than the atmosphere) may be the main supplier of carbon for sea ice microorganisms. [less ▲]

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See detailInstitutional Investors, Information Asymmetry, Stock Market Liquidity
Sougné, Danielle ULg; Aymen, Ajina; Faten, Lakhal

in International Journal of Managerial Finance (in press), 11

Purpose. The purpose of this study is to examine the effect of institutional investors ownership and activism on information asymmetry and stock market liquidity in France. Design/methodology/approach ... [more ▼]

Purpose. The purpose of this study is to examine the effect of institutional investors ownership and activism on information asymmetry and stock market liquidity in France. Design/methodology/approach. Our sample includes 162 French-listed firms over a period ranging from 2007 to 2009. Our methodology relies on linear regressions using the method of ordinary least square(OLS). Befor examining the interaction between liquidity and institutional investors, we check for the existence of the endogeneity problem by applying the Durbin-Wu_Hausman test of Davidson and MacKinnon (1993). The results of the endogeneity test show that institutional investor ownership and stock liquidity are endogenous. A simultaneous equation model using the second least square method is then tested to address this problem. Findings The findings show that the proportion of institutional investors has a positive and significant effect on stock-market liquidity, which confirms the signal theory and trading hypothesis. These investors perform high trading activity which favourably affect market liquidity. The results suggests that pension funds manage huge assets decreasing transaction costs and improving liquidity. They display a positive signal to the market about more transparency and a low level of information asymmetry.These results highlight the institutional investors'role in defining the level of liquidity of assets on the French market. Our findings also stress the importance of developing institutional investors'demand for the Paris market in order to better assess firms'values, protect minority ownership and improve market liquidity. Originality/Value In the French institutional setting, institutional investors act as a control device since minority shareholder interests are less protected than in Anglo-American counterparts. This result highlights the significant rôle of institional investors in corporate governance structures and a finacila markets. Their prsence is a guarantee for minority interest protection and for improving market liquidity. [less ▲]

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See detailDe wet Breyne. Vergelijkende beschouwingen
Kohl, Benoît ULg

in Carette, N. (Ed.) Handboek Wet Breyne (in press)

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See detailLes "nouvelles" règles générales d'exécution des marchés publics. Commentaire de l'arrêté royal du 14 janvier 2013
Kohl, Benoît ULg; Leroy, S.

in Durviaux, Ann-Lawrence (Ed.) La réforme du droit des marchés publics (in press)

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See detailInternational Construction Arbitration Law
Kohl, Benoît ULg

in Jenkins, J. (Ed.) b-Arbitra (in press)

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See detailPerformance of Global Mutual Funds
Sougné, Danielle ULg

in Filbeck, Greg; Baker, Kent (Eds.) Mutual Funds-building blocks for Investment Portfolios (in press)

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See detailAu seuil de l’Histoire de ma vie : la Préface en trois versions des mémoires de Casanova (1791, 1794, 1797)
Tilkin, Françoise ULg

in Annales Littéraires de Franche-Comté (PUFC). (in press)

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See detailError analysis of generalized-alpha Lie group time integration methods for constrained mechanical systems
Arnold, Martin; Bruls, Olivier ULg; Cardona, Alberto

in Numerische Mathematik (in press)

Generalized-alpha methods are very popular in structural dynamics. They are methods of Newmark type and combine favourable stability properties with second order convergence for unconstrained second order ... [more ▼]

Generalized-alpha methods are very popular in structural dynamics. They are methods of Newmark type and combine favourable stability properties with second order convergence for unconstrained second order systems in linear spaces. Recently, they were extended to constrained systems in flexible multibody dynamics that have a configuration space with Lie group structure. In the present paper, the convergence of these Lie group methods is analysed by a coupled one-step error recursion for differential and algebraic solution components. It is shown that spurious oscillations in the transient phase result from order reduction that may be avoided by a perturbation of starting values or by index reduction. Numerical tests for a benchmark problem from the literature illustrate the results of the theoretical investigations. [less ▲]

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See detailGeometric interpretation of a non-linear beam finite element on the Lie group SE(3)
Sonneville, Valentin ULg; Cardona, Alberto; Bruls, Olivier ULg

in Archive of Mechanical Engineering (in press)

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See detailThe contribution of the research on Latin texts to the French quantitative linguistics : from lemmatization to the grammaticometry and textual topology
Longrée, Dominique ULg; Mellet, Sylvie

in Loiseau, Sylvain; Leon, Jacqueline (Eds.) Quantitative Linguistics in France (in press)

Detailed reference viewed: 6 (0 ULg)