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See detailPour une sémiotique des pratiques émergentes, ou: à quoi pense un médium?
Badir, Sémir ULg; Provenzano, François ULg

in Badir, Sémir; Provenzano, François (Eds.) Pratiques émergentes et pensée du médium (2017)

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See detailPratiques émergentes et pensée du médium
Badir, Sémir ULg; Provenzano, François ULg

Book published by Academia-L'Harmattan (2017)

Qu’y a-t-il de commun entre le street art, les mooc ou les forums médicaux en ligne ? Il s’agit, dans tous les cas, de pratiques culturelles qui dépendent fortement des techniques qui en soutiennent ... [more ▼]

Qu’y a-t-il de commun entre le street art, les mooc ou les forums médicaux en ligne ? Il s’agit, dans tous les cas, de pratiques culturelles qui dépendent fortement des techniques qui en soutiennent l’émergence dans l’espace public. Le projet du présent volume est d’interroger ces pratiques émergentes pour la pensée médiatique qu’elles délivrent. La perspective d’analyse est sémiotique et se décline à travers une série d’études de cas qui cartographient notre imaginaire culturel contemporain. [less ▲]

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See detailAssessment of landslide hazard in the environmental hotspot areas of the Kyrgyz Tien-Shan: Spatial analysis and Numeric modelling
Torgoev, Almazbek ULg

Doctoral thesis (2017)

This PhD research was initiated in parallel with the Nato Science for Peace project “Prevention of Landslide Dam Disasters in the Tien Shan, Kyrgyz Republic”. During this project a large amount of ... [more ▼]

This PhD research was initiated in parallel with the Nato Science for Peace project “Prevention of Landslide Dam Disasters in the Tien Shan, Kyrgyz Republic”. During this project a large amount of thematic data on slope instabilities and landslide dams in the Kyrgyz Tien-Shan was collected. The thesis uses this information to investigate applied and fundamental aspects of the regional mapping of the landslide susceptibility, hazard and, partially, risk. The target areas selected for the PhD research are the Mailuu-Suu River Valley (southern Kyrgyzstan) and the surroundings of the Minkush settlement (central Kyrgyzstan). They represent the areas of former uranium mining hosting numerous storage sites of tailing material and waste rock. Additionally, these areas are characterised by a high level of landslide activity induced by the human and environmental impacts. The landslides in those areas present a high risk to the society and infrastructure, potentially triggering serious environmental consequences. Structurally, the thesis is composed of two parts: Part A and Part B. These parts are different both with respect to the research methodology and the scientific targets. The common goal of both parts is the development effective techniques to regionally assess landslide hazard in mountainous areas marked by complex geomorphological, tectonic and geological settings. Due to the remote access, such areas are often lacking background information and in-situ data that are required for the precise prediction of landslide occurrence and impacts. In such cases the spatial analysis often helps to better characterise regional and, partly, local landslide susceptibility. The regional studies allow us to outline the basic relationships between affecting factors and landslide occurrence. Such results also become the basis for effective planning of in-situ investigations and localised measurements. Part A of thesis is focused on the applied aspects of spatial analysis. This part assembles a set of the well-established approaches and methods to model landslide susceptibility, hazard and risk. The studies start with the compilation of database spatially combining various thematic information. The first type of such thematic data is represented by the multi-temporal landslide inventories. These inventories are extracted applying different sources of remote sensing data, including the satellite and aerial imagery. The second type of thematic data describes the spatial distribution of factors affecting the level of landslide activity. The mapping of affecting factors is performed by applying conventional remote sensing techniques and spatial analysis tools. The collected thematic data are then used to extract the landslide susceptibility, hazard and risk maps. In total, four conceptually different approaches are applied to map the landslide susceptibility, both on a qualitative and quantitative basis. The results of the quantitative susceptibility mapping and thematic data are further used to calculate the landslide hazard for each part of the studied area. The calculated landslide hazard is characterized both by spatial and temporal components. The results of the landslide hazard assessment are finally used to estimate the risk of the direct impacts of landslides on selected exposed elements, including the uranium tailings sites. One of the well-established approaches used in Part A is the Newmark method. It maps the seismically triggered landslide susceptibility based on the computed co-seismic displacements. The simplicity of this method is attractive to many researches around the world studying seismically-triggered landslide hazards. Nevertheless, the simplifications adopted in this method strongly limit the reliability of the final predictions. In the second part of thesis we provide a critical overview of the Newmark method and attempt to propose conceptual improvements of the existing mapping practice. To reach the targeted challenges we combine the spatial analysis with the dynamic simulations in the 2D and 3D domains. The studied models represent the actual topographic and geologic settings of the landslide-prone slopes. The simulations provide acceleration time histories that are recorded in different parts of the model surface. The analyses of these records allow us to outline the amplification impacts related to the topographic and geological site effects. The modelled amplification factors are analysed with respect to their link to the local geological and topographic settings. Thus, we study how the structural or material settings of the model can impact the recorded geological amplification. Such impacting parameters can be represented by the layer thickness, inclination of the underground contacts or the contrast of the shear wave velocity (Vs) values. The 2D topographic modelling investigates the way how the pure topographic amplification factors can be predicted based on the surface morphology. The studies show that the surface curvature can be considered as a key parameter to predict the amplification factors. This idea is further investigated in the 3D modelling studies applying different input signals and the materials of varying Vs. The results of this modelling are integrated into a single database which is subjected to spatial analysis. This finally allows us to develop a simple proxy which maps the impacts of the topographic site effects based on morphological parameters extracted from the Digital Elevation Model of the target area. Additionally, the subset of the 2D dynamic tests analyses the shear displacements triggered by the seismic shaking. Those displacements are recorded in the models with simplified geometry, as well as in the ones presenting the real topographic settings. The recorded displacements are cross-correlated with parameters characterising the seismic impacts. The results of analyses allow us to develop a new law which can easily be used in the GIS-based studies. The proposed law applies a set of the conventional parameters as well as a novel predictor which has never been used by any regional law before.The conceptual improvements proposed in Part B are finally tested by applying them to the geodatabase compiled in the first part of thesis. Related results are then compared with those that were produced by using the conventional Newmark method. The validation tests should assess performance of the developed proxies to improve the predictions of seismically-triggered landslides. [less ▲]

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See detailEnhanced silicate weathering of tropical shelf sediments exposed during glacial lowstands: a sink for atmospheric CO2
Wan, Shiming; Clift, Peter D.; Zhao, Debo et al

in Geochimica et Cosmochimica Acta (2017), 200

Atmospheric CO2 and global climate are closely coupled. Since 800 ka CO2 concentrations have been up to 50% higher during interglacial compared to glacial periods. Because of its dependence on temperature ... [more ▼]

Atmospheric CO2 and global climate are closely coupled. Since 800 ka CO2 concentrations have been up to 50% higher during interglacial compared to glacial periods. Because of its dependence on temperature, humidity, and erosion rates, chemical weathering of exposed silicate minerals was suggested to have dampened these cyclic variations of atmospheric composition. Cooler and drier conditions and lower non-glacial erosion rates suppressed in situ chemical weathering rates during glacial periods. However, using systematic variations in major element geochemistry, Sr-Nd isotopes and clay mineral records from Ocean Drilling Program Sites 1143 and 1144 in the South China Sea spanning the last 1.1 Ma, we show that sediment deposited during glacial periods was more weathered than sediment delivered during interglacials. We attribute this to subaerial exposure and weathering of unconsolidated shelf sediments during glacial sealevel lowstands. Our estimates suggest that enhanced silicate weathering of tropical shelf sediments exposed during glacial lowstands can account for ~9% of the carbon dioxide removed from the atmosphere during the glacial and thus represent a significant part of the observed glacial-interglacial variation of ~80 ppmv. As a result, if similar magnitudes can be identified in other tropical shelf-slope systems, the effects of increased sediment exposure and subsequent silicate weathering during lowstands could have potentially enhanced the drawdown of atmospheric CO2 during cold stages of the Quaternary. This in turn would have caused an intensification of glacial cycles. We attribute this to subaerial exposure and weathering of unconsolidated shelf sediments during glacial sealevel lowstands. Our estimates suggest that enhanced silicate weathering of tropical shelf sediments exposed during glacial lowstands can account for ~9% of the carbon dioxide removed from the atmosphere during the glacial and thus represent a significant part of the observed glacial-interglacial variation of ~80 ppmv. As a result, if similar magnitudes can be identified in other tropical shelf-slope systems, the effects of increased sediment exposure and subsequent silicate weathering during lowstands could have potentially enhanced the drawdown of atmospheric CO2 during cold stages of the Quaternary. This in turn would have caused an intensification of glacial cycles. [less ▲]

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See detailInstances for the 3D Multiple Bin Size Bin Packing Problem
Paquay, Célia ULg; Limbourg, Sabine ULg; Schyns, Michael ULg

Textual, factual or bibliographical database (2017)

The subject of this work is to solve the problem of packing a set of shipments (various cuboid boxes) into containers of various shapes without wasting loading space. All the boxes have to be loaded and ... [more ▼]

The subject of this work is to solve the problem of packing a set of shipments (various cuboid boxes) into containers of various shapes without wasting loading space. All the boxes have to be loaded and few are identical. As it is the case for all the packing problems, the packing has to satisfy geometry constraints: the items cannot overlap and have to lie entirely inside the bins. The richness of our application is to manage additional and common constraints: the bin weight capacity, the rotations of the boxes, the stability and the fragility of the boxes and the uniformity of the weight distribution inside the ULDs. The last constraint is crucial in air transportation: when ULDs are packed inside the airplane, the centre of gravity is computed assuming each ULD has a centre of gravity close to the geometrical centre of its basis. This type of constraints can be adapted to road transportation for the axle weight limits, which plays a key role since the weigh-in-motion systems become more common. [less ▲]

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See detailSystématiser les associations. Le concept hjelmslévien de paradigme et son héritage greimassien
Badir, Sémir ULg; Cigana, Lorenzo ULg

in Signata. Annales des Sémiotiques = Annals of Semiotics (2017), 8

This paper aims to explore the notion of “paradigm” by following its development in the epistemology of linguistics and semiotics of the twentieth century through three landmarks: its first use within ... [more ▼]

This paper aims to explore the notion of “paradigm” by following its development in the epistemology of linguistics and semiotics of the twentieth century through three landmarks: its first use within linguistics, by Ferdinand de Saussure, its redefinition by Louis Hjelmslev, and its reinterpretation in textual semiotics by Algirdas J. Greimas. The concept of “paradigm” represents, more than others, the very target of structuralist theorisation. Marking the transition between openness and closeness of linguistic categories, it crystallises the structuralist ambition to bring the dynamic variability and richness of semiotic phenomena back to a closed, or at least stable, inventory of functional ground elements. [less ▲]

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See detailAn intermediary's geographical expansion choice under uncertainty
Lefevre, Mélanie ULg; Tharakan, Joseph ULg

E-print/Working paper (2017)

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See detailLe non bis in idem en droit de la concurrence : un monde de différence avec le pénal ?
Van Cleynenbreugel, Pieter ULg

in Franssen, Vanessa; Thiel, Delphine (Eds.) EXISTE-T-IL ENCORE UN SEUL NON BIS IN IDEM AUJOURD'HUI ? (2017)

Ce chapitre analyse l'application du principe de non bis in idem dans le contexte du droit européen de la concurrence, la comparant aux applications du même principes dans de domaines connexes.

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See detailRobust asymptotic tests for the equality of multivariate coefficients of variation
Aerts, Stéphanie ULg; Haesbroeck, Gentiane ULg

in TEST (2017), 26(1), 163-187

In order to easily compare several populations on the basis of more than one feature, multivariate coefficients of variation (MCV) may be used as they allow to summarize relative dispersion in a single ... [more ▼]

In order to easily compare several populations on the basis of more than one feature, multivariate coefficients of variation (MCV) may be used as they allow to summarize relative dispersion in a single index. However, up to date, no test of equality of one or more MCV's has been developed in the literature. In this paper, several classical and robust Wald type tests are proposed and studied. The asymptotic distributions of the test statistics are derived under elliptical symmetry, and the asymptotic efficiency of the robust versions is compared to the classical tests. Robustness of the proposed procedures is examined through partial influence functions of the test statistic, as well as by means of power and level influence functions. A simulation study compares the performance of the classical and robust tests under uncontaminated and contaminated schemes, and the difference with the usual covariance homogeneity test is highlighted. As a by-product, these tests may also be considered in the univariate context where they yield procedures that are both robust and easy-to-use. They provide an interesting alternative to the numerous parametric tests of comparison of univariate coefficients of variation existing in the literature, which are, in most cases, unreliable in presence of outliers. The methods are illustrated on a real data set. [less ▲]

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See detailPreliminary assessment of the possibilities of the Particle Finite Element Method in the numerical simulation of bird impact on aeronautical structures
Cerquaglia, Marco Lucio ULg; Deliège, Geoffrey ULg; Boman, Romain ULg et al

in Procedia Engineering (2017)

As well known, in the analysis of bird impact events the bird is often reduced, even experimentally, to a surrogate projectile modeled as a weakly compressible fluid (typically a mixture of water and air ... [more ▼]

As well known, in the analysis of bird impact events the bird is often reduced, even experimentally, to a surrogate projectile modeled as a weakly compressible fluid (typically a mixture of water and air). From a numerical standpoint, the presence of a free surface and the strong interaction with the aircraft structures represent a limit for traditional computational fluid dynamics methods based on an Eulerian grid. On the other hand, classical Lagrangian methods cannot cope with the extremely large deformations experienced by the projectile during the impact. The Particle Finite Element Method (PFEM) is a Lagrangian particle method that can account for very large deformations, preserving the robustness and generality of the finite element method, and thus owning a key advantage over other approaches, e.g. Smoothed Particle Hydrodynamics (SPH), usually cursed with consistency and stability issues. To assess the possibilities of the method in the context of bird impact, theoretical analyses are initially performed based on the impact of a water jet on a rigid surface. Then, the influence of the geometry of a more realistic projectile is analyzed and the capability of the method to take into account separation and fragmentation is highlighted. [less ▲]

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See detailPlaton héritier de Protagoras. Un dialogue sur les fondements de la démocratie
Gavray, Marc-Antoine ULg

Book published by Vrin (2017)

Protagoras est un sophiste, les sophistes sont les ennemis de Platon… De ce syllogisme, la conclusion semble évidente. Elle appelle cependant quelques nuances. Plus qu’un ennemi, Protagoras apparaît en ... [more ▼]

Protagoras est un sophiste, les sophistes sont les ennemis de Platon… De ce syllogisme, la conclusion semble évidente. Elle appelle cependant quelques nuances. Plus qu’un ennemi, Protagoras apparaît en effet chez Platon comme une figure exemplaire, un interlocuteur valable qui, à travers son affirmation selon laquelle l’homme est la mesure de toutes choses, incarne la démocratie, ses conditions et ses conséquences. Ce livre traite le thème général, et classique, de l’opposition entre sophistique et philosophie, mais en le limitant à une seule question dont il déploie les différentes facettes : l’idée de mesure. Il reconstitue une pensée « protagoréenne » qui replace Platon dans son contexte intellectuel et montre comment, à travers la figure de Protagoras, c’est le débat avec la démocratie qui se joue, non seulement en tant que régime politique, mais aussi en tant que modèle théorique aux implications multiples (épistémologiques, morales, pédagogiques, techniques). Sur quel critère fonder la mesure ? Comment concevoir l’expertise et le savoir ? Quel rôle attribuer au langage dans l’éducation ? Que faire de l’identité du sujet dans le processus de mémoire ? Comment penser l’unité de la Cité ? Autant de questions soulevées dans le dialogue avec le modèle protagoréen. Comprendre ce que Platon doit à Protagoras, c’est ainsi chercher par quels éléments cette pensée l’a mis au défi et par réaction à quoi il a élaboré sa propre théorie de la mesure, de l’expertise, de l’éducation et de l’unité politique. [less ▲]

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See detailArtefact présente Tante Leny. L'underground hollandaise importée en France
Crucifix, Benoît ULg

Article for general public (2017)

Brève analyse du rôle de passeur culturel joué par Artefact dans leurs traductions de la bande dessinée underground hollandaise, via le collectif Tante Leny presenteert!.

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See detail'Mourning and Metafiction in Peter Carey's Chemistry of Tears'
Delrez, Marc ULg

in Collier, G, Davis, G; Ledent, B (Eds.) The Cross-Cultural Legacy: Critical and Creative Writings in Memory of Hena Maes-Jelinek (2017)

Peter Carey’s recent novel shares the concern with ‘unoriginality’ which has become a hallmark of his later fiction. It can actually be argued that, through this new variation on a known theme, he ... [more ▼]

Peter Carey’s recent novel shares the concern with ‘unoriginality’ which has become a hallmark of his later fiction. It can actually be argued that, through this new variation on a known theme, he purports to move beyond the clichéd postmodern paradox that authenticities – whether psychological or aesthetic – are always essentially made up, in order to consider the matter from another angle, pondering the perilous moment when an overtly fabricated object somehow mysteriously springs to life. If, as the title suggests, even our most personal emotions can be rationalized in terms of chemical reactions, why then could we not pursue a reverse path of investigation and envisage material reality as the source providing the components for the creation of spirit? This is the subjective context in which the protagonist Catherine, who works as a horologist (clockwork expert) in a London museum, must reconstruct a nineteenth-century mechanical swan suspected by some to be harbouring the soul of its original maker. Interestingly Catherine, herself a die-hard rationalist, finds herself shaken by a devastating bereavement which makes her unusually open to any form of consolation – including the self-indulgence of nostalgia, but also of cocaine and alcohol – which is why she will whole-heartedly embrace the welcome distraction offered by her work of mechanical reconstruction. As part of her attempt to understand the structure of the automaton, she feels that she must immerse herself in the diaries left behind by the commissioner of the work, an Englishman named Henry Brandling animated by his faith that the elaborate toy may release enough energy in his consumptive son, Percy, to save him from his otherwise lethal condition. Thus Carey creates an opening into the rationalist fabric of his protagonist’s present, allowing her to entertain anachronistic fantasies about the life-saving (let alone life-giving) properties of true art. Inasmuch as Catherine’s perusal of the diaries eventually facilitates a circuitous confrontation of her own grief, so that her excursions into the past serve to shore up her fragile sense of a future, the text appears to vindicate its own fantastic claims about the demiurgic, or at least redemptive, powers of art. Perhaps predictably, some reviewers balked in the face of this species of self-promotion, repeating the oft-expressed view that Carey’s fiction, in view of its deliberate straining of the laws of credibility, finally fails to emerge from an enmeshment in its own favoured themes of forgery and imitative inadequacy. The ultimate question asked by the work is then whether it must be seen to be equal to its own promise of transcendence. The present paper, by way of its own descent into the past (and particularly through a comparison with My Life as a Fake which rehearses similar themes), will try to provide an answer, notably by circumscribing the intention of a text in which metafiction assumes a metaphysical dimension possibly unique in Carey’s corpus. [less ▲]

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See detailIntegrating production scheduling and vehicle routing decisions at the operational decision level: A review and discussion
Moons, Stef; Ramaekers, Katrien; Caris, An et al

in Computers & Industrial Engineering (2017), 104

Production scheduling and vehicle routing are two well-studied problems in literature. Although these supply chain functions are interrelated, they are often solved sequentially. This uncoordinated ... [more ▼]

Production scheduling and vehicle routing are two well-studied problems in literature. Although these supply chain functions are interrelated, they are often solved sequentially. This uncoordinated approach can lead to suboptimal solutions. In the current competitive business environment, companies are searching for methods to save costs and improve their service level. Integrating production and distribution scheduling operations can be an approach to improve the overall performance. This paper focuses on integrated production-distribution operational level scheduling problems, which explicitly take into account vehicle routing decisions of the delivery process. Existing literature on integrated production scheduling and vehicle routing problems is reviewed and classified. Both the problem characteristics of mathematical models and the accompanying solution approaches are discussed to identify directions for further research. [less ▲]

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See detailMachine Learning of Real-time Power Systems Reliability Management Response
Duchesne, Laurine ULg; Karangelos, Efthymios ULg; Wehenkel, Louis ULg

in PowerTech Manchester 2017 Proceedings (2017)

In this paper we study how supervised machine learning could be applied to build simplified models of real-time (RT) reliability management response to the realization of uncertainties. The final ... [more ▼]

In this paper we study how supervised machine learning could be applied to build simplified models of real-time (RT) reliability management response to the realization of uncertainties. The final objective is to import these models into look-ahead operation planning under uncertainties. Our response models predict in particular the real-time reliability management costs and the resulting reliability level of the system. We tested our methodology on the IEEE-RTS96 benchmark. Among the supervised learning algorithms tested, extremely randomized trees, kernel ridge regression and neural networks appear to be the best methods for this application. Furthermore, by using feature “importances” computed by tree-based ensemble methods, we were able to extract the most relevant variables to predict the response of real-time reliability management, and thus obtain a better understanding of the system properties. [less ▲]

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See detailMicrostructural and functional correlates of glutamate concentration in the posterior cingulate cortex.
Arrubla Martinez, Jorge Andres ULg; Farrher, Ezequiel; Strippelmann, Johanna et al

in Journal of Neuroscience Research (2017)

Glutamate is the major excitatory neurotransmitter in the human brain and has a central role in both intrinsic and stimulus-induced activity. We conducted a study in a cohort of healthy, male volunteers ... [more ▼]

Glutamate is the major excitatory neurotransmitter in the human brain and has a central role in both intrinsic and stimulus-induced activity. We conducted a study in a cohort of healthy, male volunteers in which glutamate levels were measured in the posterior cingulate cortex (PCC) using 1H magnetic resonance spectroscopy at 3T. The advantages of simultaneous electroencephalography and magnetic resonance imaging (EEG-MRI) were exploited and the subjects were measured in the same session and under the same physiological conditions. Diffusion tensor imaging (DTI), functional MRI (fMRI) and EEG were measured in order to investigate the functional and microstructural correlates of glutamate. The concentration of glutamate (institute units) was calculated and those values were tested for correlation with the metrics of resting state fMRI, DTI, and EEG electrical sources. Our results showed that the concentration of glutamate in the PCC had a significant negative correlation with the tissue mean diffusivity in the same area. The analysis of resting state networks did not show any relationship between the concentration of glutamate and the intrinsic activity of the resting state networks. The concentration of glutamate showed a positive correlation with the electrical generators of alpha-1 frequency and a negative correlation with the generators of alpha-2 and beta-1 electrical generators. (c) 2017 Wiley Periodicals, Inc. [less ▲]

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See detailTumor host-interface in metastatic dissemination and adaptation to treatment
Sounni, Nor Eddine ULg

Scientific conference (2017)

Detailed reference viewed: 17 (2 ULg)