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See detailExcitation of nodal diameter mode-shapes of a stator ring of a turbojet engine using a limited number of excitation sources
Nyssen, Florence ULg; Golinval, Jean-Claude ULg; Viguié, Régis et al

in Proceedings of ASME Turbo Expo 2013 (2013, June 05)

When considering engine tests, the sensors used to monitor the rotor parts mainly consist in strain gauges whose information is very sensitive to the gauge positioning, especially in high stress gradient ... [more ▼]

When considering engine tests, the sensors used to monitor the rotor parts mainly consist in strain gauges whose information is very sensitive to the gauge positioning, especially in high stress gradient regions. Therefore, to reduce the risk of misinterpreting the response given by the gauges, their calibration is required. Because strain gauges are positioned so that specific modes will be monitored, their calibration must be carried out for these modes. For cyclic symmetric structures, their high spectral density imposes the use of dedicated calibration techniques. In the present paper, the concept of modal appropriation is investigated as the first step of the calibration procedure. This paper aims at presenting the development of an experimental approach enabling the isolation/appropriation of specific nodal diameter modes of a stator stage of an axial compressor using a limited number of excitation sources. A special emphasis has been brought to the minimum number and the optimized location of the excitation sources (shakers) required in laboratory conditions to appropriate specific nodal diameter modes and thereby retrieve the related modal features needed for the gauges calibration and mechanical design. [less ▲]

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See detailExcitation of the FUV Io tail on Jupiter: Characterization of the electron precipitation
Gérard, Jean-Claude ULg; Gustin, Jacques ULg; Grodent, Denis ULg et al

in Journal of Geophysical Research. Space Physics (2002), 107(A11),

[1] Spectral observation of both polar regions of Jupiter in the far ultraviolet (FUV) obtained with the Space Telescope Imaging Spectrograph (STIS), on board the Hubble Space Telescope from July 1997 to ... [more ▼]

[1] Spectral observation of both polar regions of Jupiter in the far ultraviolet (FUV) obtained with the Space Telescope Imaging Spectrograph (STIS), on board the Hubble Space Telescope from July 1997 to January 2001 have been combined with FUV images to map the FUV color ratio along the STIS slit. Spatially resolved spectra of the aurora carried at similar to12 Angstrom resolution have been used to determine the amount of methane absorption as measured by the FUV color ratio of the Io magnetic footprint and its trailing tail. It is found that the absorption is systematically less than in the main polar aurora, indicating a higher altitude source region. The color ratio of the north tail is shown to slowly decrease downstream from the footprint. The combination of these spectral data with a two-stream model of the interaction of energetic electrons with the Jovian thermosphere indicates that the mean energy of the electrons creating the north FUV emission ranges from similar to55 keV at the Io footprint to similar to40 keV, 20 degrees downstream in the tail. In parallel, the incident electron energy flux drops by a factor similar to6 over the same angular distance. These observations are consistent with the steady state slippage picture where the subcorotating flux tube is accelerated very slowly up to corotation owing to the nonideal coupling. It is argued that small deviations from corotation can supply sufficient energy to fuel the observed auroral emissions. It is suggested that the parallel electric field accelerating electrons out of the flux tube only moderately depends on the time elapsed since the contact with Io, although the mapping between a point in the tail and Io is very uncertain in the presence of magnetic field line slippage. [less ▲]

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See detailExcitation processes and pulsations in the polar aurora
HARANG, O.; Gérard, Jean-Claude ULg

in Bulletin de la Société Royale des Sciences de Liège (1973)

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See detailExcitation spectrum of FE2+ in a tetrahedral potential - Dynamic Jahn-Teller effect
Colignon, David ULg; Kartheuser, Eduard ULg; Rodriguez, Sergio et al

in Physical Review. B : Condensed Matter (1995)

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See detailExcited baryons in the 1/Nc expansion.
Matagne, Nicolas; Stancu, Floarea ULg

in AIP Conference Proceedings (2012), 1432

We briefly describe the 1/Nc expansion method for studying baryon masses. Two approaches of the large Nc excited baryons have been proposed so far. The first one, based on the Hartree picture, treats the ... [more ▼]

We briefly describe the 1/Nc expansion method for studying baryon masses. Two approaches of the large Nc excited baryons have been proposed so far. The first one, based on the Hartree picture, treats the baryon as a ground state core and an excited quark and the second one, suggested recently, considers the baryon globally, without decoupling the system. The masses of excited states of mixed orbital symmetry of nonstrange and strange baryons belonging to the lowest [70, −] multiplet are calculated in the 1/Nc expansion to order 1/Nc with the new method which allows to considerably reduce the number of linearly independent operators entering the mass formula. The status of the resonance Λ(1405) is discussed. [less ▲]

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See detailExcited (70,l+) baryon resonances in large N(c) QCD
Matagne, Nicolas; Stancu, Floarea ULg

in Nucl. Phys. Proc. Suppl. (2007), 174

We summarize results obtained in the $1/N_c$ expansion method for the masses of baryon resonances belonging to the $[{\bf 70},\ell^+]$ multiplet. They represent an extension of our previous studies from ... [more ▼]

We summarize results obtained in the $1/N_c$ expansion method for the masses of baryon resonances belonging to the $[{\bf 70},\ell^+]$ multiplet. They represent an extension of our previous studies from two to three flavors. A better approach to mixed symmetric states of any angular momentum and parity is also outlined. [less ▲]

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See detailExcited [70,l(+)] baryons in large N-c QCD
Matagne, Nicolas; Stancu, Floarea ULg

in Physics Letters B (2005), 631(1-2), 7-15

The masses of the positive parity [70, 0(+)] and [70, 2(+)] non-strange baryons are calculated in large N-c QCD by considering the most dominant operators in an 1/N-c expansion. The approach is based on ... [more ▼]

The masses of the positive parity [70, 0(+)] and [70, 2(+)] non-strange baryons are calculated in large N-c QCD by considering the most dominant operators in an 1/N-c expansion. The approach is based on the introduction of an excited core, obtained after the last particle (an excited quark) has been removed. Configuration mixing is neglected, for simplicity. Although being a sub-leading 1/Nc order, we find that the spin-spin interaction plays a dominant role in describing the data. The role of No operators is also pointed out. We show how the contribution of the linear term in Nc, of the spin-spin and of the spin-orbit terms vary with the excitation energy. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]

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See detailExcited baryons in the 1/N(c) expansion
Matagne, Nicolas; Stancu, Floarea ULg

in World Scientific (2005)

We review results for the mass spectrum of orbitally excited baryons obtained in the $1/N_c$ expansion. We show the dependence of various contributions to the mass operator as a function of the excitation ... [more ▼]

We review results for the mass spectrum of orbitally excited baryons obtained in the $1/N_c$ expansion. We show the dependence of various contributions to the mass operator as a function of the excitation energy. [less ▲]

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See detailExcited states of gaseous ions. Transition to and predissociation of the C2 sigma U+ state of N2+
Lorquet, Jean-Claude; Desouter, Michèle ULg

in Chemical Physics Letters (1972), 16

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See detailExciter les sens pour bouleverser les cœurs : les processions post-tridentines dans les régions de culture baroque
Delfosse, Annick ULg

in Psychoyou, Théodora (Ed.) Musiques et réformes religieuses aux XVIe et XVIIe siècles : statuts, fonctions, pratiques (2008)

During the decades following the Council of Trent, Reformed Catholicism - particularly in the areas marked by Baroque culture - came to know heightened modes of expression, and religious ceremonies ... [more ▼]

During the decades following the Council of Trent, Reformed Catholicism - particularly in the areas marked by Baroque culture - came to know heightened modes of expression, and religious ceremonies reached a remarkable level of grandeur. The author focuses the paper on both the "ordinary" and "extraordinary" processions of the post-Tridentine liturgy. Following a reminder about what a procession is and brief comments about the ceremonial and disciplinary rules laid down by Rome and the diocesan authorities, she envisions these processions as multi-sensory phenomena of which she underlines the dimension of sound. Finally, she shows how this over-stimulation of the senses allowed the faithful to lose themselves in God. [less ▲]

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See detailExciton dissociation at donor-acceptor heterojunctions: Dynamics using the collective effective mode representation of the spin-boson model
Chenel, Aurélie; Mangaud, Etienne; Burghardt, Irène et al

in Journal of Chemical Physics (2014), 140

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See detailAn exclosure experiment to assess the impact of ungulates on plant diversity in Belgium
VANDENSCHRICK, François; Lehaire, François ULg; Licoppe, Alain ULg et al

Poster (2013, August)

The erosion of biodiversity is caused by many factors. Large ungulates, which occupy a large part of the Walloon forests, can also influence the distribution and dynamics of plant species. Therefore, they ... [more ▼]

The erosion of biodiversity is caused by many factors. Large ungulates, which occupy a large part of the Walloon forests, can also influence the distribution and dynamics of plant species. Therefore, they impact the biodiversity of our temperate forests. The aim of the present study is to identify changes in forest understory vegetation due to the pressure exerted by wild ungulates thanks to an exclosure-enclosure experiment. This study was conducted on a high plateau of the Ardenne, in the forest of St Michel Freyr (South Belgium). The forested area is dominated by beech and spruce where red deer, wild boar and roe deer are living in sympatry. 150 sampling plots were established in 2000. Each plot consisted of two closed enclosures of 4 m² each and one exclosure of 4 m² as control under pressure of ungulates. Sampling was carried out systematically by a 500m-square mesh. The cover rate and height of some easily identifiable species were measured regularly since 2000 (2001, 2002, 2003, 2004, 2007, 2011-2012). In addition, we identified each herbaceous species in 2011-2012 to analyze the species richness after more than 10 years exclosure. Ligneous species showed an increase of developpement in the fenced area. These species are more impacted when they are not much represented in the study site.Species richness and diversity are higher in areas impacted by herbivory. Monocotyledons are mainly favorised while tree seedlings are unfavorised. Browsing on the trees keeps the area free from high vegetation and allows light to reach the ground. In the same time, herbaceous species have a lower cover rate in the enclosure because of the competitive exclusion induced by shrub and tree seedlings layer. If the apparition of most species is favorised by ungulates, they induce a lag of gowth on dicotyledons which have a higher palatability than monocotyledons. Ungulates have the ability to impact the distribution of vegetal species by the modification of the competitive interaction. By their pressure on tree and shrub species, they induce a higher diversity of the ground flora. However, this change in vegetation composition is slow and requires a long-term studie, specially in areas of low biomass productivity like the St-Hubert forest. [less ▲]

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See detailExclusion de l'assurance chômage et réinsertion sur le marché du travail
de Lathouwer, L.; Bogaerts, K.; Perelman, Sergio ULg

Report (2000)

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See detailL'exclusion de la réassurance des règles européennes de conflits de juridictions en matière de contrats d'assurance
Boularbah, Hakim ULg

in Bulletin des Assurances = Tijdschrift voor Verzekeringen (2002)

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See detailExclusion en Science humaine – Exclusion en Province de Liège
Jamin, Jérôme ULg

Conference given outside the academic context (2005)

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See detailL'exclusion et le retrait non judiciaires dans les sociétés à responsabilité limitée
Aydogdu, Roman ULg

in Droit des Affaires : Revue Internationale du Droit des Affaires = Ondernemingsrecht : Internationaal Tijdschrift voor Ondernemingsrecht [= DA OR] (2007)

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See detailL'exclusion et le retrait non-judiciaires dans les sociétés à responsabilité limitée
Caprasse, Olivier ULg; Aydogdu, Roman ULg

in Droit des Affaires : Revue Internationale du Droit des Affaires = Ondernemingsrecht : Internationaal Tijdschrift voor Ondernemingsrecht [= DA OR] (2007)

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See detailExclusion et sciences humaines
Jamin, Jérôme ULg

Report (2004)

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See detailExclusion of farmers as a consequence of quality certification and standardisation
Vuylsteke, Anne; Van Huylenbroeck, Guido; Collet, Eric et al

in Cahiers Options Méditerranéennes (2005), 64

During the past decades, Belgian and European agriculture encountered several crises and as a result, food safety and quality have become governmental issues. This has led to vertical coordination and the ... [more ▼]

During the past decades, Belgian and European agriculture encountered several crises and as a result, food safety and quality have become governmental issues. This has led to vertical coordination and the appearance of quality conventions between links in the food supply chain. In practice, the quality conventions initiated by changed institutional settings turned out to be compulsory. This research aims to assess the exclusion-effect of this process and this is undertaken through data-analysis concerning farmers' participation in certification initiatives and homogeneity analysis. The results of a survey concerning 319 Belgian farmers show that 25% of the farmers are not involved in any initiative of quality improvement. They are significantly older and less educated, but have also very little access to farmers' organisations and extension. Their gross margin is lower in comparison with participants; they are more oriented to one specialisation and are less labour intensive. The combination of these elements can be seen as a constraint to enter initiatives and as a probable danger to exclude the concerned farmers from the market. This paper further elaborates upon these results, but also studies farmers' opinion regarding laws, contracts and labels. Finally, some recommendations towards public policies are made. [less ▲]

Detailed reference viewed: 37 (1 ULg)