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See detailLes 20 ans du Cifen : bienvenue
Simons, Germain ULiege

Speech/Talk (2015)

Mot de bienvenue aux participants à la cérémonie des 20 ans d'existence officielle du Centre interfacultaire de formation des enseignants (Cifen) de l'ULg

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See detailWhy are flux avalanches deflected by a metallic layer?
Brisbois, Jérémy ULiege

Poster (2015, August 27)

Sudden avalanches of magnetic flux bursting into a superconducting sample are deflected from their trajectories when encountering a conductive layer deposited on top of the superconductor. Remarkably, in ... [more ▼]

Sudden avalanches of magnetic flux bursting into a superconducting sample are deflected from their trajectories when encountering a conductive layer deposited on top of the superconductor. Remarkably, in some cases the flux is totally excluded from the area covered by the conductive layer. Even if experimental evidence of the phenomenon has been available for a few years, there is currently no theoretical model to describe it. Moreover, the question whether a single vortex would also undergo deflection when entering the region covered by a metallic layer is still unanswered. In this work we use the magneto-optical imaging (MOI) technique, based on the Faraday effect, to show that a conductive layer (Cu) can repel flux avalanches triggered in an underlying superconducting film (Nb). We present a simple classical model that accounts for the deflection of a single vortex and considers a magnetic monopole approaching a semi-infinite conductive plane. This model suggests that electromagnetic braking, arising from the eddy currents induced in the metal due to the moving vortex, is an important mechanism responsible for avalanche deflection. Furthermore, we have found that early theoretical descriptions for the vortex damping enhancement due to the metallic sheet need a correction at large vortex velocities, where a decrease of the damping coefficient is expected. [less ▲]

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See detailElicitor screening to protect wheat against Zymoseptoria tritici
Le Mire, Géraldine ULiege; SIAH, ALI; Deleu, Magali ULiege et al

Conference (2015, August 27)

Plants face an array of biotic and abiotic stresses in their environment, making it necessary to use various chemical inputs to maintain satisfactory yield. Today, conventional agriculture is evolving ... [more ▼]

Plants face an array of biotic and abiotic stresses in their environment, making it necessary to use various chemical inputs to maintain satisfactory yield. Today, conventional agriculture is evolving towards more sustainable practices, out of respect for human health and the environment. Elicitors are considered as promising biological control tools and draw major interest in IPM strategies. These plant-immunity triggering compounds, also called “stimulators of plant natural defenses”, induce a general and systemic resistance in the plant to various diseases. Although numerous elicitors have already been identified and some of them reached the market since the late 1970s, further investigations are still required to better understand the mode of action of these molecules in the plant and ensure a consistent efficiency under various field conditions. Few elicitors have yet been successfully tested and formulated to protect monocotyledonous crop plants such as wheat, which is cultivated over large areas in Europe. This study focuses on the screening of ten potential elicitor products of various origins and structures to protect winter wheat against the fungal pathogen Zymoseptoria tritici. Greenhouse trials were carried out to measure the ability of the different products to reduce disease foliar symptoms (necrosis, chlorosis and pycnidia). Topical spraying treatments with 3 different concentrations of each product were carried out 5 days before pathogen inoculation. Disease severity (% of symptoms on the total surface of the third leaf) was then scored every 2 days up to 28 days post-inoculation. In addition, phytotoxicity and biocide activity of these products was evaluated under greenhouse and laboratory conditions, respectively. The corresponding results will be presented and discussed with the perspective to choose the best elicitor candidates and to undertake investigations on the signaling pathway and the influence of environmental parameters on the elicitation capacity. [less ▲]

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See detailRamses goes Online. An annotated corpus of Late Egyptian texts in interaction with the Egyptological community
Polis, Stéphane ULiege; Rosmorduc, Serge; Winand, Jean ULiege

Conference (2015, August 27)

The Ramses project was first introduced to Egyptologists in 2008, during the 10th interna-tional congress of Egyptologists held in Rhodes (Winand et al. in press). After eight years of IT developments ... [more ▼]

The Ramses project was first introduced to Egyptologists in 2008, during the 10th interna-tional congress of Egyptologists held in Rhodes (Winand et al. in press). After eight years of IT developments (under the responsibility of S. Rosmorduc) and of annotation of Late Egyptian texts (Polis et al. 2013; Polis & Winand 2013), the data can now progressively be made available online. After an introduction providing general information about the annotated corpus (510 000+ tokens; 65 000+ hieroglyphic spellings; 10 000+ lemmata; 4000+ texts), this paper will focus on three main aspects: 1. Description of the functionalities of the annotating tool (the TextEditor), with a special attention to the metadata that are used for describing the documents and texts that are integrated in the corpus. This section will include proposals regarding the creation of shared thesauri for describing (written) Egyptian material. 2. Discussion of the solution that has been designed for handling the evolution of the database (see already Rosmorduc 2013), both as regards its content — namely, any change that affects texts, lemmata, inflexions, spellings, etc. — and its structure — types and structure of the metadata, evolution of the texts representation format, etc. In a nutshell, the new database will use the technique of event sourcing, where the database is seen as a sequence of editing events, which allows both “time travel” in the database history, and easy fix of editing mistakes. 3. Presentation of the first Online version of Ramses. Several corpora of Late Egyptian texts (the so-called Tomb Robberies, the Late Egyptian Stories, the Late Ramesside letters and a selection of ostraca from Deir el-Medineh) will be made available for the first time at the occasion the 11th International Congress in Florence. The website will of course allow users to browse the annotated texts and lexemes, and to make simple or complex queries. Besides, we will also encourage Egyptologists to interact directly with the data, e.g., by flagging inaccuracies or signaling alternative analysis. [less ▲]

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See detailA shared repository of hieroglyphic signs: The Thot sign-list
Polis, Stéphane ULiege; Rosmorduc, Serge

Conference (2015, August 27)

The principles to be taken into consideration for building a hieroglyphic sign list have been discussed for quite some time (Schenkel 1977), and recently received renewed and additional attention (Meeks ... [more ▼]

The principles to be taken into consideration for building a hieroglyphic sign list have been discussed for quite some time (Schenkel 1977), and recently received renewed and additional attention (Meeks 2013, Polis & Rosmorduc 2013). The catalogs of hieroglyphic signs (e.g. Buurman et al. 1988, Grimal et al. 1993), however, did not implement these principles, since their goal was rather to allow for the encoding and rendering (either on paper or on screen) of as many hieroglyphs as possible. As a result, hieroglyphic text editors (Gozzoli 2013) will usually do the trick when one aims at displaying hieroglyphic texts, but in its current state, the Manuel de Codage makes the creation of annotated corpora that include hieroglyphs problematic (Nederhof 2013). In this paper, we do not focus on issues pertaining to the relative positioning of hieroglyphs (Nederhof 2002), but on another — more essential — problem, namely the hieroglyphic sign-list itself. Existing sign-lists suffer from the fact that they are (1) unstructured, (2) unreferenced, and (3) non-described. Based on our experience with respect to the encoding of hieroglyphic spellings in the Ramses corpus (Polis et al. 2013; Polis & Winand 2013), we present a beta version of the Thot sign-list, which has the following features (see the discussion in Polis & Rosmorduc 2013): 1. The sign-list is structured: each hieroglyph of the sign-list belongs to one of the three following categories: grapheme, class and shape (from the more abstract to the more concrete, see also Meeks 2013). 2. Signs are referenced: each sign is accompanied by at least one reference to a publication in which the hieroglyph is used in context. For this purpose, the unpublished lists of hieroglyphic signs compiled by Hornung and Schenkel have been instrumental. We are much grateful to both of them for sharing this material with us and allowing us to use it in this context. 3. Signs are described at two levels: a. The functions that each hieroglyph can fulfill (Polis & Rosmorduc in press), with illustrative examples for each function. b. The salient iconic features of each hieroglyph, based on a controlled vocabulary. Practically, the Thot sign-list is a Wiki, i.e., a web application that allows collaborative modification of its content and structure. Thanks to the Semantic Mediawiki extension, one can create links between any signs sharing a given property. The goal is obviously to allow any Egyptologist to enrich the structured sign-list Thot with new signs, references and descriptions. [less ▲]

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See detailA new dictionary of Ancient Egyptian
Winand, Jean ULiege

Conference (2015, August 27)

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See detailGeophysical Investigation of the Pb-Zn deposit of Lontzen-Popplsberg, Belgium
Evrard, Maxime ULiege

Conference (2015, August 26)

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See detailMise en place d’un système de mesure par covariance de turbulence des flux de N2O sur une parcelle agricole
Lognoul, Margaux ULiege

Master's dissertation (2015)

Nitrous oxide (N2O) is a greenhouse gas responsible for 8% of anthropogenic radiative forcing. It is also a major contributor to stratospheric ozone depletion. Agricultural soils represent its main source ... [more ▼]

Nitrous oxide (N2O) is a greenhouse gas responsible for 8% of anthropogenic radiative forcing. It is also a major contributor to stratospheric ozone depletion. Agricultural soils represent its main source. N2O is produced by microorganisms through nitrification and denitrification processes. Both depend on oxygenation conditions and nitrogen and labile carbon availability, which are driven by soil and climate conditions and by farming practices. Yet there remain science gaps concerning the understanding of emission mechanisms and dynamics. The eddy covariance technique allows studying a whole ecosystem with a half-hourly temporal resolution, opening up for long-term monitoring and precise greenhouse gas budget calculation. However, this technique requires a specific expertise. In order to install such a system to measure N2O exchanges by a production crop at the Terrestrial Observatory of Lonzée (Belgium), we set the following goals : (1) establishing the state of knowledge concerning N2O fluxes exchanged by crops and identifying gaps, (2) setting up a N2O analyzer at the experimental site and providing operating procedures, and (3) building and adjusting the first data processing and calculation procedures. As a result of this work, scientific gaps were identified and avenues for further research are suggested. Monitoring and data acquisition routines as well as first data processing procedures were implemented. Numerous questions still remain regarding the adaptation of classical methods (created to study CO2) to N2O, and they constitute the investigation prospects of this work. [less ▲]

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See detailEtude de la biodégradation anaérobie des feuilles de Mangifera indica (manguier) et de Manihot utilissima (manioc)
Mambanzulua Ngoma, Philippe ULiege

Doctoral thesis (2015)

The population growth of these last two decades leaded to an increase of waste in the City Province of Kinshasa (VPK), capital of the Democratic Republic of Congo. Deprived by an effective management ... [more ▼]

The population growth of these last two decades leaded to an increase of waste in the City Province of Kinshasa (VPK), capital of the Democratic Republic of Congo. Deprived by an effective management system, the VPK produces essentially vegetal wastes that are constituted for the greater part of dead leaves. These wastes bother and pollute the environment. On another point of view, the Kinshasa households meet enormous difficulties for soil fertilization and to collect wood for energy. Its overexploitation of the wood entails the deterioration of the ecosystems and the public health. Therefore in order to contribute to the reduction of all these difficulties simultaneously, the aim of this thesis was to investigate the methanization of these wastes since this technique is relatively simple, fast and non expensive. So, the methanation was performed at 30°C on the leaves of Mangifera indica (MU, mango) and of Manihot utilissima (MI, cassava) that are the most accessible of the VPK. The biochemical methane potentials of the MU and MI leaves demonstrated that the MU leaves were favorable to the methanation due to their low content in bioactive substance (secondary metabolites) and their low C/N ratio. In addition, their digestates would be an effective fertilizing. By contrast, the MI leaves were unfavorable to the methanation since the methanogenesis was inhibited, probably because of their composition rich in carbon and secondary metabolites (lignine, polyphenols, saponines and anthraquinones). However, these metabolites would be beneficial for the methanation in lower contents than 0.3 g/l in the culture medium. The anaerobic co-digestion improved the daily methane yields of these two leaves. The biogas produced with this process would represent about 28 % of the wooden annual domestic consumption and its digestate would cover annually the all agricultural and forest degraded areas. So, the domestic methanation or on site or near the site of waste generation would be favored to avoid the cost of their transport and their industrial treatment. A promising pilot essay has been achieved. [less ▲]

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See detailThe harmonic balance method for bifurcation analysis of large-scale nonlinear mechanical systems
Detroux, Thibaut ULiege; Renson, Ludovic ULiege; Masset, Luc ULiege et al

Conference (2015, August 26)

The harmonic balance (HB) method is widely used in the literature for analyzing the periodic solutions of nonlinear mechanical systems. The objective of this paper is to extend the method for bifurcation ... [more ▼]

The harmonic balance (HB) method is widely used in the literature for analyzing the periodic solutions of nonlinear mechanical systems. The objective of this paper is to extend the method for bifurcation analysis, i.e., for the detection and tracking of bifurcations of nonlinear systems. To this end, an algorithm that combines the computation of the Floquet exponents with bordering techniques is developed. A new procedure for the tracking of Neimark-Sacker bifurcations that exploits the properties of eigenvalue derivatives is also proposed. As an application, the frequency response of a structure spacecraft is studied, together with two nonlinear phenomena, namely quasiperiodic oscillations and detached resonance curves. This example illustrates how bifurcation tracking using the HB method can be employed as a promising design tool for detecting and eliminating such undesired behaviors. [less ▲]

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See detailNegative Relative Clauses in Late Egyptian. A Functional Perspective
Sojic, Nathalie ULiege

Poster (2015, August 26)

The poster contains a functional taxonomy of the negative relative clauses in Late Egyptian

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See detailOutils d’aide à la réussite dans le cadre du cours de Biologie en Premier bachelier en Faculté des Sciences à l’Université de Liège : présentation et analyse
Thiry, Marc ULiege; Rigo, Pierre ULiege; Poffé, Corentin ULiege

Conference (2015, August 26)

A l’Université de Liège, les cours du premier quadrimestre sont communs à certaines sections du premier bachelier de la Faculté des Sciences. Le programme de ce quadrimestre commun reprend un cours de ... [more ▼]

A l’Université de Liège, les cours du premier quadrimestre sont communs à certaines sections du premier bachelier de la Faculté des Sciences. Le programme de ce quadrimestre commun reprend un cours de biologie. Depuis plusieurs années, le titulaire de ce cours de biologie met en place diverses actions visant à favoriser la transition secondaire-université : séminaires, remédiations, aides à l’étude, forum, livre de référence, etc. Ces différentes actions font l’objet d’un suivi didactique, permettant un monitoring précis et une régulation au fil du temps. Dans un premier temps, la communication présentera l’état des lieux des outils mis à la disposition des étudiants en vue de favoriser leur réussite pour le cours de biologie, mais aussi pour les autres cours, par transfert des compétences acquises. Dans un second temps, le dispositif de suivi didactique des séances d'aide à l'étude et ses principaux résultats seront présentés. [less ▲]

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See detail"Reden und Rufe": are they kingly patterns?
Motte, Aurore ULiege

Poster (2015, August 26)

Les discours des travailleurs, ou « Reden und Rufe », sont principalement connus grâce aux travaux d’Erman et Guglielmi [1]. Malgré quelques faiblesses, ceux-ci sont toujours les seuls ouvrages de ... [more ▼]

Les discours des travailleurs, ou « Reden und Rufe », sont principalement connus grâce aux travaux d’Erman et Guglielmi [1]. Malgré quelques faiblesses, ceux-ci sont toujours les seuls ouvrages de référence disponibles. Ce travail ambitionne de s’intéresser aux origines des discours des travailleurs. Quand, où, comment, pourquoi émergent-ils ? Autant de questions laissées jusqu’ici sans réponses. Après une brève remise en contexte des « Reden und Rufe », il sera montré que les discours des travailleurs sont une partie intégrante du « nouveau » programme décoratif royal, dont l’apothéose est atteinte sous Sahourê. Ce papier présentera également les premières réceptions de ces discours dans les tombes privées et leur évolution au sein de l’élite (mise en évidence de traditions phraséologiques, d’adaptation et d’innovation). Il sera montré que les discours des travailleurs s’inscrivent dans la tradition égyptienne de l’élite, qui reprend à son compte des motifs d’origine royale pour établir son propre programme décoratif. [1] A. ERMAN (1919), Reden, Rufe und Lieder auf Gräberbildern des Alten Reiches, Berlin (APAW philos.-hist. Kl., Abh. 15). W. GUGLIELMI (1973), Reden, Rufe und Lieder auf altägyptischen Darstellungen der Landwirtschaft, Viehzucht, des Fisch- und Vogelfangs vom Mittleren Reich bis zur Spätzeit, Bonn, Habelt (TÄB 1). [less ▲]

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See detailAnthropogenic landscape change: synthesis of the concepts and quantification methods
Andre, Marie ULiege; Vranken, Isabelle ULiege; Mahy, Grégory ULiege et al

Conference (2015, August 26)

Anthropogenic disturbances impact the whole biosphere, at least indirectly, and are of major concern in various disciplines and policies. To tackle it, most studies, specific to their thematic, create ... [more ▼]

Anthropogenic disturbances impact the whole biosphere, at least indirectly, and are of major concern in various disciplines and policies. To tackle it, most studies, specific to their thematic, create their own reference framework without connection with related purposes in other disciplines. This results in a plethora of terms and concepts that in turn impedes addressing that issue on a comprehensive way as well as complementarity between studies. Here, we clarify and synthesize the most frequently employed terms to characterise human impact on the environment (anthropisation, naturalness, hemeroby, novel ecosystem, analogous ecosystem, climax, etc.), their synonyms, the nuances and relationships between each of them, as well as the concepts used to designate the responses given by humans to environmental disturbances (restoration, management, conservation). We go on reviewing the methods used to assess anthropogenic changes, exploring different branches of ecology and geography. The strengths and weaknesses of the existing approaches are then used as a basis to develop a new analytical framework: we propose an action-oriented type of naturalness, and we develop a general methodology to quantify landscape anthropisation. Our methodology combines object-oriented and gradient analyses. Moreover, it is based on the assessment of ecosystem disturbance, landscape configuration and dynamics as well as on easily acquired data sets. Our integrated approach of the concern could be at the basis of land planning, environmental restoration and management practices as well as policies. [less ▲]

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See detailperrénité et mutations des familles : approche sociologique
Gavray, Claire ULiege

Conference (2015, August 26)

remise en cause des clichés concernant l'évolution de La Famille ; discussions autour des enjeux contemporains et futurs qui concernent les familles

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See detailDoes combining a wheat and pea mixture with methyl salicylate reduces aphid populations in both crops?
Chevalier Mendes Lopes, Thomas ULiege; Fassotte, Bérénice ULiege; Hatt, Séverin ULiege et al

Conference (2015, August 25)

Aphids are important pests of wheat and pea. Among the alternative methods to control them with less reliance on insecticides, crop associations already proved to be efficient. However, if increasing the ... [more ▼]

Aphids are important pests of wheat and pea. Among the alternative methods to control them with less reliance on insecticides, crop associations already proved to be efficient. However, if increasing the chemical and structural complexity of vegetation can disrupt their host plants location, the searching efficiency of predators and parasitoids can also be reduced. Therefore, these beneficials may not always be more abundant in such systems. Combining crop associations with attractive semiochemicals for natural enemies can be interesting to solve this problem. In this research, we compared the effect of a wheat and pea pure stand, wheat and pea mixture, and wheat and pea mixture combined with methyl salicylate (MeSA) formulated in alginate gel beads, on the abundance and diversity of aphids and their natural enemies. These were weekly observed on plants during 2013 and 2014 growing seasons. Over these two years, significantly higher numbers of pea aphids (Acyrthosiphon pisum (H.)) were observed in the pure stand of pea compared with both mixtures (with and without MeSA). No significant differences were observed between treatments for wheat aphids (Sitobion avenae (F.), Metopolophium dirhodum (W.) and Rhopalosiphum padi (L.)), which were significantly less abundant than pea aphids. Aphid natural enemies were mainly observed on pea plants. Hoverfly larvae abundance was not significantly different between treatments during both years. The same phenomenon occurred with hoverfly pupae in 2013, while these were significantly more abundant in both mixtures compared with the pure stand in 2014. However, their number did not differ significantly between the mixture with and without MeSA. Few ladybirds and lacewings were observed. No significant differences were observed between treatments for parasitoid mummies in 2013. Their abundance was significantly higher in the pure stand of pea compared with both mixtures in 2014. Results from this study show that mixing wheat and pea is an efficient method to maintain aphid populations at a very low level on pea. The use of MeSA did not show significant effects on natural enemies. However, mixing these crops may be enough to reduce aphid populations under an acceptable threshold. [less ▲]

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See detailDu satellite au terrain. Observation de la surface terrestre et processus géographiques
Cornet, Yves ULiege

Scientific conference (2015, August 25)

53ème Congrès des Professeurs de Sciences 2015 Proposition d’Yves CORNET (CC, Photogrammétrie et télédétection, Geomatique, ULg) Sujet : « Du satellite au terrain » Forme : Brève Introduction théorique ... [more ▼]

53ème Congrès des Professeurs de Sciences 2015 Proposition d’Yves CORNET (CC, Photogrammétrie et télédétection, Geomatique, ULg) Sujet : « Du satellite au terrain » Forme : Brève Introduction théorique suivie d’un atelier Durée totale : 1h30 Résumé : Je proposerai tout d’abord un bref rappel des notions de « couleur » (vrai couleur, fausse couleur, fausse couleur de synthèse) en visualisation d’images polygéniques enregistrées par des capteurs satellitaires récentes disponibles gratuitement dans les archives de l’USGS et couvrant le territoire wallon (ex. capteur OLI à bord de Landsat 8). Ensuite, j’élargirai la discussion en établissant le lien avec le concept de signature et résolution spectrales pour en arriver à deux applications très exploitées par les géographes et qui reposent sur ces concepts. La première application est la classification d’image. La seconde application est l’extraction de paramètres bio-géo-physiques à partir d’images multi-spectrales en exploitant les parties du spectre permettant cette détermination (ex. couleur des océans - rapports de réflectance entre les canaux visibles permettant de mettre en évidence l’absorption du rayonnement lumineux par la chlorophylle). Nous limiterons notre discours à la partie du spectre dans laquelle le soleil éclaire la surface terrestre (visible et proche infra-rouge) qui est celle la plus facile à appréhender pour des écoliers du secondaire. Ensuite pendant l’atelier, j’exploiterai de façon intuitive l’analyse graphique car elle constitue une spécificité de formations scientifiques et, malheureusement, je constate depuis plusieurs années, de la part de la majorité de nos étudiants, une réelle incapacité de s’exprimer de cette façon. Il me semble que cette compétence peut être aisément exercée par des exercices simples tels que ceux que je proposerai en limitant au maximum l’accès à des outils logiciel. Les données nécessaires à ces analyses graphiques seront fournies ou extraites d’images à l’aide d’outils logiciels de visualisation d’images gratuits qui seront mis à la disposition des enseignants pour qu’ils puissent préparer de nouvelles activités dans leur classe. Les réalisations graphiques seront effectuées sur papier quadrillé. Elle permettront par exemple de représenter la position d’un pixel dans l’espace multispectral (diagramme de dispersion bi-variés combinant les canaux 2 par 2 et éventuellement tri-variés en combinant les canaux par 3), de construire des courbes de signature spectrale de différents type de couverture du sol dans différents contextes topographique et donc dans des conditions d’illumination différentes, de construire des courbes de signature spectrales d’une eau non turbide présentant des concentration en chl-a variable (données fournies). Nous accorderons une attention particulière à la signification physique des valeurs reportées sur les différents axes (unités, ordres de grandeur, variations) et un protocole d’interprétation de ces graphiques sera ensuite proposé. D’une part, nous comparerons les signatures spectrales de différents types de couverture du sol généralement reconnus par classification d’image (surface herbeuse, canopée, sol nu, surface bétonnée, surface macadamisée, eau …). Pour certains types de couverture du sol, nous mettront en évidence l’effet topographique qui est d’autant plus marqué que la longueur d’onde exploitée se rapproche du proche infra-rouge en raison de la réduction de la diffusion du rayonnement solaire incident pour les plus grande longueurs d’onde du visible et le proche infra-rouge que pour les courtes longueur d’onde du visible. Pour limiter la complexité des interprétations, nous limiterons les analyses à des données instantanées (pas de variation temporelle !!). D’autre part, dans la partie consacrée à l’analyse de la couleur des océans nous proposeront la construction différente graphique (diagramme de dispersion ou validation et histogrammes) permettant de mettre en relation le résultat de l’extraction de paramètres bio-optiques de l’eau depuis des images satellitaire et son correspondant mesuré sur le terrain. Nous expliquerons ainsi la signification graphique des notions de biais, d’imprécision et d’incertitude. Nous établirons alors quelques liens entre le processus d’acquisition des images satellitaires (angle d’observation, champs instantané d’observation du capteur satellitaire, résolution radiométrique, influence de l’état de surface des mers et ses interaction avec la géométrie de l’éclairement solaire vis-à-vis de l’observation, altération atmosphériques …) et la signification d’un échantillon des valeurs de référence sur le terrain (campagne de mesure de la concentration de chlorophylle en mer ou dans des lac, dynamique spatiale et temporelle, représentativité spatiale et temporelle). [less ▲]

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See detailThe ‘Landscape’ of Nuclear Safeguards: a Comparative Analysis of the International and Regional Systems
Colussi, Ilaria Anna ULiege

Poster (2015, August 24)

Nuclear proliferation poses a severe threat to the international community, and the role of the law in this area is crucial. The notion of ‘nuclear non-proliferation’ is twofold: (a)disarm or vertical non ... [more ▼]

Nuclear proliferation poses a severe threat to the international community, and the role of the law in this area is crucial. The notion of ‘nuclear non-proliferation’ is twofold: (a)disarm or vertical non-proliferation: measures for reduction of the number of existing arsenals; (b)horizontal non-proliferation: containment of the number of States and no State entities that do not have but are acquiring nuclear weapons, or developing the capability and materials for producing them. Different sources of the law exist at the international and regional level for addressing the issue. For the implementation of the principles and obligations embedded in the agreements, it is essential to set up a verification and safeguards system. Safeguards provisions are established at the international and regional level. Thus, the aim of this study to analyse, critically and comparatively, the different safeguards systems that have been legally adopted at the international and regional level so far. [less ▲]

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See detailDoes elevation in atmospheric CO2 concentration impact aphid alarm signaling?
Boullis, Antoine ULiege; Appeldoorn, Claire; Oostrom, Marjolein et al

Poster (2015, August 24)

The effect of global atmospheric changes on interactions between vegetation and phytophagous insects is well studied since several years, but how does these changes affect the interactions between ... [more ▼]

The effect of global atmospheric changes on interactions between vegetation and phytophagous insects is well studied since several years, but how does these changes affect the interactions between herbivore insects and their natural enemies is less clear. Impact of an increase in CO2 concentration on aphids is also well documented, but few publications focused on their chemical ecology. When endegered, aphids emit an alarm pheromone (generally composed of only one molecule: (E)-Beta-Farnesene) to induce an escape behavior in the colony. Here, we studied how an increase in CO2 concentration affects the alarm signaling mechanisms of the aphid Acyrthosiphon pisum, focusing on the production, the emission (under attack) and the perception of this signal. [less ▲]

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