Last 7 days
Bookmark and Share    
Full Text
See detailSocialisation et articulation des régimes d'historicités
Grandjean, Geoffrey ULg

Conference given outside the academic context (2016)

Detailed reference viewed: 8 (1 ULg)
See detailLa concurrence mémorielle et la lutte contre le racisme
Grandjean, Geoffrey ULg

Conference given outside the academic context (2016)

Detailed reference viewed: 10 (3 ULg)
Full Text
See detailBerge-acyclic multilinear 0-1 optimization problems
Buchheim, Christoph; Crama, Yves ULg; Rodriguez Heck, Elisabeth ULg

E-print/Working paper (2016)

Detailed reference viewed: 12 (3 ULg)
See detailPerspectives sur la mise en scène : un art en recherche
Delhalle, Nancy ULg

Conference given outside the academic context (2016)

Detailed reference viewed: 10 (0 ULg)
Full Text
See detailEvaluation des impacts des projets de développement sur les exploitations agricoles familiales et les ménages de l’ATACORA (Nord-Ouest du Benin)
Tohinlo, Yecy ULg

Doctoral thesis (2016)

This doctoral research aims to contribute to a better understanding of the effects of development projects on the improvement of living conditions and livelihoods of rural households in Benin. It begins ... [more ▼]

This doctoral research aims to contribute to a better understanding of the effects of development projects on the improvement of living conditions and livelihoods of rural households in Benin. It begins with the analysis of development trends in Atacora known about the last three decades. It is focused on matching between the dynamics promoted by intervention devices and those endogenous or emerging to lead a part in the consideration of the productive trajectories and performance of family farms and also in the analysis of effects of development projects on food security, living standards and poverty of rural households. The post-development theories and the various conceptions of poverty have served as a guideline for research work. The intervention mechanisms conducted in Atacora (north-western Benin) by the various cooperations (bilateral and multilateral) between 1990 and 2010 constituted the research object of this thesis. The empirical phase took place in the communes of Cobly (West) and Péhunco (East). These communes were selected from their contrasting agro-ecological and socio-economic situations and socio-economic indicators on the one hand and on the other on a typology of the concentration of development projects and the perception of their effects by local people. A stratified sample of 344 households (respectively 214 in Cobly and 130 in Péunco) was formed for the characterization survey. Later, a thorough investigation on living conditions and livelihood of households followed and involved 208 households (129 Cobly; 79 Péhunco). Finally 16 case studies (8 per commune) were conducted on the trajectories of evolution and accumulation of property and wealth of households and farms. Due to the empirical research, special attention was given to primary data collection which lasted more than three (3) years. Qualitative and quantitative tools (including PSM) were combined for the analysis of collected data through individual and group interviews. Results show that the development interventions do not always promote the endogenous dynamics but they generate and maintain, in rural areas, pathways that allow the integration and participation of producers in the world market for agricultural products. And to benefit from various promotional activities, producers adopt supported crops, this have some positive and negative consequences. The integration and participation of rural producers of Atacora to international trade, promote the increase of production and crop yields while further increasing their dependence on the world prices of agricultural products. So while the income of producers is increasing their vulnerability to food insecurity is also increasing because many of the food crops, already insufficient (because of the share of the cotton planted and the cotton production quotas established by the government) to cover food needs, are substracted from consumption to be sold on the market to meet urgent liquidity needs. Thereby, Atacora's rural households, despite the increase of their food production, suffered a rupture of food stocks resulting to annual food crises of at least 4 months (16 weeks) which strikes indiscriminately both recipient households than non-project beneficiaries. However with the increase of sources and income level of recipient households (36% of households of the study sites), those beneficiaries improve their homes and food consumption and invest more in the education of their children. This marks a significant difference between beneficiaries and non-beneficiaries of development projects. Indeed, installed with the same resources, we counted, in 2014, twice more prosperous households and fewer poor among beneficiaries than non-beneficiaries. Furthermore farms and households beneficiaries of assistance have accumulated and hold more productive assets (land, farm equipment, livestock rearing), economic assets and holdines (transportation measures, housing, plots and houses to rent, etc.) than non-beneficiaries with a highly significant difference at 1%. However the level of improvements and living conditions induced by development interventions are still inadequate and insecure, as reduced to the equivalent adult,income as well as capital show no significant difference between beneficiaries and non-beneficiaries. Thus, households (even beneficiaries) remain vulnerable to crises so that any natural disaster (flood, drought, pest invasion, etc.), illness, injury and death of a member of the household, provokes the rapid degradation of living standards and the fall into poverty. This is compounded by the fact that farms owners’ don’t invest really in the restoration and enhancement of the capital '' land fertility ''; mainly in Cobly where the soil fertility level experienced a drastic decline with a consequent increasing use of chemical fertilizers that degrade the soil structure furthermore. It follows that any action aimed at poverty reduction should allow a sustainable improvement in conditions and livelihoods of rural producers by the preservation and restoration of soil fertility on the one hand and the increased resilience to crises on the other hand. Actions to identify specific needs with measures and solutions adapted to each category of producers and households with mainly particular mechanisms of management and restoration of the fertility of agricultural land shall be considered and implemented. [less ▲]

Detailed reference viewed: 25 (13 ULg)
Full Text
See detailL'Afrique centrale: entre traditions et transitions. La mutation des socio-écosystèmes en Afrique centrale
Gillet, Pauline ULg

Doctoral thesis (2016)

The forests of the Congo Basin are among the best preserved areas on Earth. Nevertheless, the factors causing deforestation around the world are also present in this subregion. The forest transition ... [more ▼]

The forests of the Congo Basin are among the best preserved areas on Earth. Nevertheless, the factors causing deforestation around the world are also present in this subregion. The forest transition theory describes how the trend of forest areas decline at national level may precede an increase in these areas. If the effects of the forest transition are well known in terms of forest cover degradation, little is known about the effects of forest transition on socio-ecosystems (SES) (understood as a group of actors with impacts on a group of resources and subject to specific institutions). The general objective of this thesis is to characterize the mutation of socio-ecosystems in the Congo Basin in order to identify dynamic of change of Congo Basin forested SES and their possible futures. The collection of socioeconomic data, focusing on the description of the population, the description of the different activities and incomes, the description of food intake and the access to land and resources, were conducted in three SES with a forest cover gradient, located in Cameroon and Gabon. The results show that the cost price of meals is globally increasing with the loss of forest cover. The share of food intake related to the exploitation of natural resources such as hunting, fishing and gathering decreases in favor of proteins from livestock and agricultural products. This leads to the translocation of demand but also to pressures on other anthropogenic ecosystems. The effects of deforestation are then visible at the local level but also on neighboring areas. The diversity of the game and prey decreases moving towards smaller species with the progression of the forest transition. Consequently, there is a reduction in the proportion of these products in both the food intake and household incomes. This analysis shows a decline in the importance of NTFPs in the production and villagers livelihoods. Slash and burn agriculture is practiced in three SES. If the ratio between fallow period and cultivation period decreases with the forest transition, there is an increase in crop diversification leading to a diversification of the diet. Access to forest resources, agricultural land, markets and an external source of employment condition the village activities. The land potential is made to report levels of ownership and co-management of customary space (Le Roy et al., 1996). During the progression of the forest transition curve, the land potential evolves from relatively loose to privatization and the ability to alienate resources. These important modifications of traditional control systems of the relations between man and resources lead to a more adequate management of some commercial resources value (such as agricultural products or mining resources). But, this process is incompatible with the maintenance of certain ecosystem services like large populations of wildlife preservation. If these results fit rather well with the forest transition curve, this is not the case of all SES in Central Africa. Therefore, we propose to combine some results to reflect significant changes of the qualities of a socio-ecosystem, regardless of forest cover rate. The priority would be to establish a standardized data collection protocol to test sites with different forest cover and located on different trajectories. The use of a socio-economic index would make it possible to predict the evolution of SES under different scenarios, whether linked to global or regional pressures (such as the emergence plans enacted by the Central African States) or in contexts of economic crisis or the introduction of new legislation. [less ▲]

Detailed reference viewed: 40 (11 ULg)
Peer Reviewed
See detailPossible worlds: verbo-nominal patterns with chance
Van linden, An ULg; Brems, Lieselotte ULg

Conference (2016, December 02)

Detailed reference viewed: 17 (2 ULg)
Full Text
See detailOviposition deterring effect of Ocimum basilicum L. (Lamiaceae) on Tuta absoluta Meyrick (Lepidoptera: Gelechiidae)
Yarou, Boni Barthélémy ULg; Bawin, Thomas ULg; Boullis, Antoine ULg et al

Poster (2016, December 02)

Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) is one of the most important pests of tomato, reducing crop yield in greenhouses and fields, in several countries around the world. Because synthetic ... [more ▼]

Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) is one of the most important pests of tomato, reducing crop yield in greenhouses and fields, in several countries around the world. Because synthetic insecticides lead to resistance and have adverse effects on natural enemies and producers’ health, there is a need for alternatives. In this study, we assess the oviposition deterring effect of O. basilicum using dual-choice behavioral assays performed in flight tunnels. Two modalities were tested, i.e. (1) a tomato plant associated either with an O. basilicum plant versus a tomato plant associated with a plastic pot only filled with potting soil, and (2) a tomato plant with basil essential oil (EO) formulated in paraffin oil (PO) versus a tomato plant with PO only. A 1 ml cylindrical polyethylene plug loaded with 100 µl of solution (formulated EO or PO) was placed on each plant as a diffuser. Forty-eight hours after the release of unsexed adult individuals randomly sampled from the rearing in the central area of the tunnel, we found that plants and EOs reduced T. absoluta oviposition behavior on a nearby located tomato plant. GC-MS analyses showed that the major constituents include estragol (73.8%), linalool (8.6%), β-elemene (2.9%) in O. basilicum essential oils and E-α-bergamotene (38.9%), methyl eugenol (26.1 %), E-β-ocimene (17.7 % ) in O. basilicum VOCs collected with solid-phase micro-extraction method. These results suggest a valuable potential of O. basilicum and associated essential oils as component of an integrated management strategy against the tomato leafminer. [less ▲]

Detailed reference viewed: 31 (2 ULg)
Peer Reviewed
See detailDésir, mal d'enfant, stérilité
Naziri, Despina ULg

Conference (2016, December 02)

Detailed reference viewed: 22 (2 ULg)
Peer Reviewed
See detailQuelques réflexions autour d'un texte de Théodore Scaltsas
Dawans, Stéphane ULg; Houbart, Claudine ULg

Conference (2016, December 02)

Face à l’extension du champ de l’intervention sur l’existant et au brouillage des limites entre rénovation et restauration d’édifices et d’ensembles allant du monument historique au bâti générique, ancien ... [more ▼]

Face à l’extension du champ de l’intervention sur l’existant et au brouillage des limites entre rénovation et restauration d’édifices et d’ensembles allant du monument historique au bâti générique, ancien ou récent, il semble plus que jamais utile d’accepter la notion de bricolage conceptuel et de réfléchir à une « boîtes à outils » permettant aux futurs architectes de faire face à la complexité des enjeux de la réhabilitation. En effet, face à ceux-ci, les théories de la restauration monumentale qui sont enseignées dans les instituts et facultés d’architecture atteignent parfois leurs limites et nous semblent devoir être complétées par/confrontées à de nouveaux concepts ou théories susceptibles d’élargir et même de renouveler notre vision des choses. C’est ainsi que depuis plusieurs années, nous avons choisi de faire un pas de côté et d’interroger des champs aussi éloignés que la logique formelle, l’ontologie de l’art et les théories littéraires et travaillons actuellement à une anthologie critique de textes variés mais tous susceptibles d’intéresser les conservateurs (du patrimoine mobilier et immobilier) et donc aussi, les architectes intervenant sur l’existant. Parmi ces textes, oeuvres d’auteurs en grande partie méconnus dans le champ du patrimoine, « Identity, Origin and spatio-temporal continuity », du philosophe Théodore Scaltsas, professeur à l’université d’Edimbourg, et extrait d’une revue en grande partie écrite en langage mathématique, nous parait particulièrement intéressant à analyser lors du séminaire. En utilisant des exemples aisément transposables au milieu de l’architecture, il aborde notamment la question de l’intention d’une reconstruction de manière originale et interpellante, qui n’autorise plus les fréquents amalgames justifiant tout et n’importe quoi et émanant non seulement du monde économique mais aussi des milieux du patrimoine dits autorisés. Par ailleurs, il enrichit le débat sur l’authenticité d’une dimension peu prise en compte à ce jour et particulièrement éclairante dans le cas des productions modernes et contemporaines, qui constituent l’un des enjeux les plus actuels de la réhabilitation. [less ▲]

Detailed reference viewed: 19 (1 ULg)
Peer Reviewed
See detailSchizophrénie et hyperconscience : Une étude en première personne
Englebert, Jérôme ULg; Valentiny, Caroline

Conference (2016, December 02)

Detailed reference viewed: 32 (1 ULg)
Full Text
Peer Reviewed
See detailLa reconnaissance des génocides et la répression du négationnisme
Grandjean, Geoffrey ULg

in Courrier Hebdomadaire du CRISP (2016), 2304-2305

La reconnaissance politique d’un génocide et la répression de la négation de celui-ci représentent deux enjeux d’une grande importance symbolique. Surtout, elles constituent un exercice très délicat pour ... [more ▼]

La reconnaissance politique d’un génocide et la répression de la négation de celui-ci représentent deux enjeux d’une grande importance symbolique. Surtout, elles constituent un exercice très délicat pour l’autorité politique qui pose de tels actes. Il s’agit en effet de consacrer une vérité historique et de dicter le souvenir qui doit en être véhiculé. L’intervention d’une instance politique dans le champ de l’histoire et de la mémoire est toujours entourée de nombreux débats. Les discussions, souvent vives, portent sur diverses questions. Le principe d’une action législative dans un tel domaine est-il recevable et pertinent ? Quelle définition de « génocide » convient-il d’adopter ? La répression du négationnisme est-elle de nature à justifier une limitation de la liberté d’expression ? Si oui, dans quelle mesure cette restriction s’applique-t-elle aussi aux chercheurs ? Lorsqu’il s’agit d’événements historiques relatifs à un autre État, faut-il faire primer l’éthique et la morale sur la diplomatie ? Les réponses à ces interrogations fondamentales se cristallisent dans des lignes de fracture qui échappent aux clivages partisans classiques. En Belgique, les initiatives de reconnaissance des crimes de génocide et de pénalisation de leur négation sont le fait des deux chambres du Parlement fédéral. Elles ont abouti à diverses dispositions législatives, telles la loi réprimant la négation du génocide commis par le régime nazi à l’encontre des Juifs pendant la Seconde Guerre mondiale (1995), une résolution relative au génocide perpétré par l’Empire ottoman à l’encontre des Arméniens en 1915 (1998), une résolution sur le génocide des Tutsis au Rwanda en 1994 (2004) et une résolution relative à la commémoration du centenaire du génocide arménien (2015). G. Grandjean retrace et éclaire l’ensemble des débats parlementaires qui se sont tenus en Belgique depuis 1992 autour de la question de la mémoire des crimes de masse. Son Courrier hebdomadaire offre les clés de lecture pour la compréhension des débats en cours quant à une extension de la loi de 1995. [less ▲]

Detailed reference viewed: 13 (2 ULg)
Full Text
See detailLa nostra «avvelenata» (Guccini non ne ha colpa)
Curreri, Luciano ULg; Belletti, Gabriele

Article for general public (2016)

Detailed reference viewed: 14 (2 ULg)
Full Text
See detailLa fiction au défi du virtuel
Huppe, Justine ULg

Scientific conference (2016, December 02)

Dans un premier temps, nous reviendrons sur la manière dont on a tenté de définir la fiction, à partir de ses « attracteurs sémantiques » (Schaeffer, 2005), puis en nous attachant à sa définition ... [more ▼]

Dans un premier temps, nous reviendrons sur la manière dont on a tenté de définir la fiction, à partir de ses « attracteurs sémantiques » (Schaeffer, 2005), puis en nous attachant à sa définition pragmatique qui domine largement aujourd’hui (de Searle à Caïra, en passant par Walton, Currie ou encore Schaeffer). Nous interrogerons quelques uns des concepts fondamentaux de cette approche (la feintise, l’immersion, le pacte pragmatique). Ensuite, nous nous intéresserons de plus près à un imaginaire lui aussi dominant : celui de la fiction définie comme « monde » ou « ouvreuse de mondes ». Il s’agira d’éclairer les conditions historiques dans lequel ce paradigme s’est forgé (lassitude du paradigme formaliste, développement de la logique des mondes possibles, popularisation des sciences cognitives, avènement des technologies virtuelles). Dans un second temps, nous nous intéresserons précisément à ces technologies qualifiées de « virtuelles ». Nous décrirons les caractéristiques du codage numériques et les possibilités qu’il offre à la fiction, tout en le replaçant dans une histoire culturelle qui, à l’avènement de nouvelles pratiques et supports pour la fiction, a souvent vu resurgir un certain argumentaire anti-mimétique. Nous mettrons également en lumière les enjeux que le numérique représente pour la fiction : ce qu’il déstabilise (ou non), mais surtout ce qu'il questionne (immersion, identification, frontière juridique…). [less ▲]

Detailed reference viewed: 14 (0 ULg)
Full Text
See detailSpace Thermal Analysis through Reduced Finite Element Modelling
Jacques, Lionel ULg

Doctoral thesis (2016)

The finite element method (FEM) is widely used in mechanical engineering, in particular for structure design. However, it is not often exploited for the thermal analysis of space structures for which the ... [more ▼]

The finite element method (FEM) is widely used in mechanical engineering, in particular for structure design. However, it is not often exploited for the thermal analysis of space structures for which the use of the lumped parameter method is still commonplace. To alleviate the computational burden of the FEM for thermal analyses involving conduction and radiation, an innovative global conductive-radiative reduction scheme based on the clustering of the finite element mesh is presented. The proposed method leads to a significant reduction of the number of radiative exchange factors (REFs) to compute and size of the corresponding matrix. It further keeps accurate conduction information by introducing the concept of physically meaningful super nodes associated to the clusters from which are derived the reduced conductive couplings. To complement the reduction of the number of faces, an improved Monte Carlo ray tracing algorithm is developed. It provides better accuracy and convergence rate than the classic Monte Carlo method. The algorithm is adapted to the partitioned FE mesh and includes quadrics fitting for accurate normal representation. The resulting conductive-radiative reduced model is solved using standard iterative techniques and the detailed mesh temperatures, recovered from the super nodes temperatures, can be directly exploited for thermo-mechanical analysis. The proposed global reduction method is validated on several space structures and is benchmarked against ESATAN-TMS, the standard thermal analysis software used in the European aerospace industry. [less ▲]

Detailed reference viewed: 14 (2 ULg)
Full Text
See detailCooperative spontaneous emission with quantized atomic motion
Damanet, François ULg

Doctoral thesis (2016)

In this thesis, we present investigations on the cooperative dynamics of (ultra)cold atoms coupled to the electromagnetic field in vacuum. The main objective is to identify the consequences of the ... [more ▼]

In this thesis, we present investigations on the cooperative dynamics of (ultra)cold atoms coupled to the electromagnetic field in vacuum. The main objective is to identify the consequences of the quantization of the atomic center-of-mass motion on the atoms-field dynamics, more particularly the atomic \emph{internal} dynamics including dipole-dipole interactions and cooperative spontaneous emission processes. For this purpose, we derive a Markovian master equation for the internal state of a collection of two-level atoms coupled to vacuum accounting for all effects related to the quantization of their motion. These effects depend on three characteristic lengths that can be tuned experimentally: the interatomic distance $r$, the wavelength $\lambda$ of the emitted radiation, and the typical size $\ell$ of the atomic wave packets. This leads to a rich panel of phenomena depending on the hierarchy between these characteristic lengths. Our master equation provides a unifying picture of the consequences of recoil and quantum statistics (bosonic or fermionic) on both the internal dissipative and conservative dynamics, and applies equally well to distinguishable and indistinguishable atoms. It is valid even beyond the Lamb-Dicke regime, i.e.\ for large recoil effects. We give general expressions for the decay rates and the dipole-dipole shifts entering the master equation for arbitrary motional states, and we find closed-form formulas for a number of relevant states (Gaussian states, harmonic oscillator eigenstates, Bose-Einstein condensates motional states). In particular, we show they can be strongly influenced by the motional state of the atoms, which suggests the possibility to quantum program their internal dynamics through motional state engineering. Based on the derived master equation, we investigate in full detail the super- and subradiance phenomena arising from a collection of indistinguishable atoms. Due to the symmetry (for bosons) or antisymmetry (for fermions) of the global state under exchange of atoms, the internal dynamics is restricted to the permutation invariant subspace whose dimension grows as $N^2$ with $N$ the number of atoms. In this particular case, the master equation involves only three rates: a single-atom decay rate $\gamma_0$, a cooperative decay rate $\gamma$ and a collective dipole-dipole shift $\Delta_\mathrm{dd}$. We solve the dynamics exactly for $2$ atoms, numerically for up to $30$ atoms, and obtain the large-$N$ limit by a mean-field approach. We show that a superradiant enhancement of the radiated intensity is always observed for a sufficiently large number of atoms. As regards subradiance, we show that exact decoherence free subspaces that protect against spontaneous emission through destructive interference of individual spontaneous emission amplitudes exist only in the limit of classically localized atoms, i.e.\ for atoms in infinitely steep traps. We assess the validity of our master equation in the optical domain through the study of the exact atoms-field dynamics. Among others, this complementary approach gives access to the vibrational state populations of the atoms after a photon emission and to the angular dependence of the emission spectrum. It also highlights the complex interplay between the atomic internal and motional states, such as the entanglement transfer that can occur during the collective decay of the atoms. Moreover, it opens the door for the study of the non-Markovianity of the internal dynamics. In conclusion, our thesis provides a comprehensive picture of the consequences of the quantization of the atomic motion on cooperative spontaneous emission processes and contributes to the development of theoretical tools for the study of the internal dynamics of (ultra)cold atoms. [less ▲]

Detailed reference viewed: 7 (2 ULg)