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See detailActive faulting at the western tip of the Gulf of Corinth, Greece, from high-resolution seismic data
Beckers, Arnaud ULg; Hubert, Aurelia ULg; Beck, Christian et al

in Marine Geology (2015)

The Gulf of Corinth is one of the fastest-spreading intra-continental rifts on Earth. GPS data indicate that the rift is currently opening in a NNE-SSW direction, with a rate of extension reaching up to ... [more ▼]

The Gulf of Corinth is one of the fastest-spreading intra-continental rifts on Earth. GPS data indicate that the rift is currently opening in a NNE-SSW direction, with a rate of extension reaching up to 16 mm yr-1 in its westernmost part. Although the rest of the offshore rift has been well studied, the western tip of the rift is still poorly explored. We present an accurate map of submarine faults in this area based on two high-resolution seismic reflection surveys (single channel sparker). In the eastern part of the studied area, the sedimentary infill is affected by the known North Eratini, South Eratini and West Channel faults. Further to the west, the seafloor is mostly flat, and is bounded to the north by the normal, south-dipping, Trizonia fault. To the north, the shallower part of the Gulf shows to the east a diffuse pattern of normal and strike-slip deformation which is replaced to the west by a 7.5 km long SE striking strike-slip fault zone, called the Managouli fault zone. To the westernmost tip of the Gulf, in the Nafpaktos Basin, two fault sets with different strikes are encountered; the one with aNE-SW strike exhibits a clear strike-slip component. The western tip of the Gulf of Corinth is the only part of the Corinth Rift where convincing evidence for strike-slip movement has been found. This fault pattern is likely related to the complex deformation occurring at the diffuse junction at the western tip of the Rift between three crustal blocks: Continental Greece, Peloponnese, and the Ionian Island-Akarnia block. [less ▲]

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See detailThe Harmonic Balance Method for Bifurcation Analysis of Nonlinear Mechanical Systems
Detroux, Thibaut ULg; Renson, Ludovic ULg; Masset, Luc ULg et al

in Proceedings of the SEM IMAC XXXIII (2015)

Because nowadays structural engineers are willing to use or at least understand nonlinearities instead of simply avoiding them, there is a need for numerical tools performing analysis of nonlinear large ... [more ▼]

Because nowadays structural engineers are willing to use or at least understand nonlinearities instead of simply avoiding them, there is a need for numerical tools performing analysis of nonlinear large-scale structures. Among these techniques, the harmonic balance (HB) method is certainly one of the most commonly used to study finite element models with reasonably complex nonlinearities. However, in its classical formulation the HB method is limited to the approximation of periodic solutions. For this reason, the present paper proposes to extend the method to the detection and tracking of codimension-1 bifurcations in the system parameters space. As an application, the frequency response of a 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 detailCatalogue of the types and illustrated specimens recovered from the ‘black marble’ of Denée, a marine conservation-Lagerstätte from the Mississippian of southern Belgium
Mottequin, Bernard ULg; Poty, Edouard; Prestianni, Cyrille

in Geologica Belgica (2015)

The Viséan ‘black marble’ of Denée is one of the best preserved Mississippian fossil assemblages. This Lagerstätte is famous for the exceptional preservation of several groups of macro-organisms (fishes ... [more ▼]

The Viséan ‘black marble’ of Denée is one of the best preserved Mississippian fossil assemblages. This Lagerstätte is famous for the exceptional preservation of several groups of macro-organisms (fishes, echinoids, graptolites). However, only a part of the fauna has received attention from specialists and most of the phyla may benefit from a modern revision based on new investigative techniques such as 3D imagery and CT-scanning. Almost all the specimens illustrated in the literature have been traced and we present here a comprehensive catalogue of this material. Representatives of several minor groups are photographically illustrated for the first time as well as five emblematic specimens of the styracopterid genus Benedenius (Pisces). For purposes of nomenclatural formality, the lectotypes of Benedenius deneensis Traquair (in de Koninck, 1878), B. soreili Fraipont, 1890, Oligoporus soreili Fraipont, 1904, Taeniaster? fournieri Fraipont, 1904, and Scaphiocrinus longicaudatus Fraipont, 1904 are here selected. [less ▲]

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See detailGIS-Based Landslide Susceptibility Mapping in the Great Lakes Region of Africa, Case Study of Bujumbura Burundi
Nibigira, L.; Draidia, Salah ULg; Havenith, Hans-Balder ULg

in Engineering Geology for Society and Territory-Volume 2 (2015)

Abstract: Landslides in Central Africa represent a constant threat to the population. The present work took its motivation from the increasing number of recorded incidents in recent times. It is focused ... [more ▼]

Abstract: Landslides in Central Africa represent a constant threat to the population. The present work took its motivation from the increasing number of recorded incidents in recent times. It is focused on the analysis of mass movements in a regional context. Remote sensing based on the use of satellite images (Pleiades images of 2011) and aerial photographs (1957, 1958 and 1981) allowed us to identify instabilities at different scales. The study of these mass movements and the characterization of the processes governing ... [less ▲]

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See detailHazard and Risk Related to Earthquake-Triggered Landslides
Havenith, Hans-Balder ULg; Fan, X.; Torgoev, A.

in Engineering Geology for Society and Territory-Volume 2 (2015)

Abstract This paper first analyses how important earthquake-induced landslide hazards are compared to other geohazards at world-wide scale. Further, we will outline where these hazards may have the ... [more ▼]

Abstract This paper first analyses how important earthquake-induced landslide hazards are compared to other geohazards at world-wide scale. Further, we will outline where these hazards may have the strongest impacts—at regional and local scale. In this regard, we consider the short-and long-term effects of geological, tectonic, climatic and morphological conditions. Hazard and risk related to these processes will also be analysed on the basis of a series of case histories: eg, the 1920 Haiyuan earthquake-landslide disaster in China. A ... [less ▲]

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See detailLandslide Susceptibility Mapping with Data Mining Methods—a Case Study from Maily-Say, Kyrgyzstan
Braun, A.; Fernandez-Steeger, T.; Havenith, Hans-Balder ULg et al

in Engineering Geology for Society and Territory-Volume 2 (2015)

Abstract: Multiple factors, such as geology, high mountain topography, seismic activity, climatic conditions and mining activities cause significant landslide hazard in the region around Maily-Say ... [more ▼]

Abstract: Multiple factors, such as geology, high mountain topography, seismic activity, climatic conditions and mining activities cause significant landslide hazard in the region around Maily-Say, Kyrgyzstan. To assess the landslide susceptibility a database containing landslide information and geological, morphological and hydrological parameters associated with landslide occurrence was established and analyzed with different data mining algorithms. The most promising results were achieved with an Artificial Neural ... [less ▲]

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See detailWhich psychological factors influence Internet addiction? Evidence through an integrative model
Burnay, Jonathan ULg; Billieux, Joël; Blairy, Sylvie ULg et al

in Computers in Human Behavior (2015), 43

Since the appearance of Internet, several preoccupations have appeared as a result, with Internet addiction being one of the most common. The goals of the present study were two-fold. First, to examine ... [more ▼]

Since the appearance of Internet, several preoccupations have appeared as a result, with Internet addiction being one of the most common. The goals of the present study were two-fold. First, to examine which psychological factors are relevant to explain Internet addiction, including impulsivity, passion and social provision. Second, to incorporate all these factors into an integrative model. Based on multiple regressions and path analysis, results revealed a positive relation between Internet addiction and specific impulsivity components (lack of perseverance, urgency) and obsessive passion. Moreover, positive relations were observed between obsessive passion and reassurance of worth, opportunity for nurturance, sensation seeking and harmonious passion. In other words, Internet addiction is related to obsessive passion, but is explained by different psychological factors. Accordingly, both Internet addiction and obsessive passion can be viewed as two important and complementary facets of problematic Internet use. [less ▲]

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See detailCondições Semióticas da Repetição
Lindenberg Lemos, Carolina ULg

Doctoral thesis (2015)

Emanating from different areas of the human sciences, repetition was given a central role in this thesis of semiotic inclination. It is a widespread phenomenon in all fields of human activity and ... [more ▼]

Emanating from different areas of the human sciences, repetition was given a central role in this thesis of semiotic inclination. It is a widespread phenomenon in all fields of human activity and, particularly, in texts. The optional character of certain repetitions in texts brings about the problem of its function, since, in certain cases, it seems to act directly on the rhythm of the content and the flow of entrances and exits of the phenomenal field. This regulation of the rhythm divides the research into two fronts. On the one hand, the rhythmic effect points to an underlying structure. In that sense, one can ask: what is the configuration of such structure? In what way is repetition part of it? Or even, what is its place in the semiotic model? On the other hand, repetition seems to involve a certain degree of contradiction: in what way can a phenomenon that brings no novelty, only the resumption of the same, sometimes create an effect of tension or surprise? In order to answer these questions, we undertake the revision of the role of repetition in neighboring fields: rhetoric and a specific trend in linguistics. This discussion has allowed us to detect a few insufficiencies in these approaches that may be answered by semiotics. From the semiotic perspective, we have explored the place occupied by repetition, by opposing it to concepts such as identification, text, language and to the notion of semiotics itself. Once the position of repetition in the text is established, we move on to note and discuss the textual conditions necessary to the occurrence of relevant repetitions. In addition to identification, the notion of salience, based on the opposition between figure and ground, revealed itself to be central to the explanation of the phenomenon. Finally, linearity has also proven relevant, which allowed us to re-discuss its theoretical status as one possible manifestation of the underlying syntagmatic structure. Having outlined the conditions for repetition, we have started an investigation into the somewhat contradictory effects we had observed in repetitive incidents. We saw that repetition belongs to the order of extent – it is counted, not measured – and, in being so, it is a tool for the manifestation of the rhythm of the content that is presupposed by it. In these terms, repetition is subordinated to the intensive sub-dimensions: tempo and tonicity. To ensure the relevance of our arguments, we studied repetition within some selected objects, where it is made to serve of the text. Finally, the analysis of these objects shed light on the relations between repetition and the concept of aspect, and three styles of textual progression related to repetition were confirmed: circular, linear and spiraling. This path of investigation has shown us the terms which repetition is tied to and the way in which it manifests an underlying structure. It has also revealed that such structure not only explains but also generates the variations in rhythm and tempo that are felt through repetition. The apparent contradictions of the effects of repetition are explained by the very epistemological bases of the field. The analytical and relational aspects of semiotics are the basis for repetitive construction, which, without adding any new information, may lead the enunciatee to tension, climax and surprise. [less ▲]

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See detailVoyage(s) à travers le thymus
Geenen, Vincent ULg

Book published by Presses ULg (2015)

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See detailGiven to a Deity? Religious and Social Reappraisal of Human Consecrations in the Hellenistic and Roman East
Caneva, Stefano ULg; Delli Pizzi, Aurian ULg

in Classical Quarterly (2015)

Various cases of human beings ‘dedicated’ to deities are attested in Greek epigraphic evidence. Are these kinds of offerings comparable to the dedication of inanimate objects? Besides, does the fact that ... [more ▼]

Various cases of human beings ‘dedicated’ to deities are attested in Greek epigraphic evidence. Are these kinds of offerings comparable to the dedication of inanimate objects? Besides, does the fact that someone is said to be ‘sacred’ to a specific deity necessarily involve that he went through a process of dedication? This article aims at providing a global picture of different situations in which processes of dedications took place. Among the several issues that are tackled, the cornerstone of this article consists of two questions: for what purposes did some people decide to consecrate a human being to a deity and what were the consequences for the consecrated individuals on religious and social levels? Different categories of persons will be contrasted, in terms of processes through which they acquire their new status but also in terms of the freedom/lack of freedom which is conveyed by this new status. It will also be shown that, as far as method is concerned, it is necessary to complete a lexical analysis with a contextual perspective for a deeper understanding of the problem. [less ▲]

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See detailAn original solver for spillway flow
Goffin, Louis ULg; Erpicum, Sébastien ULg; Dewals, Benjamin ULg et al

Poster (2015)

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See detailQuantitative temperature monitoring of a heat tracing experiment using cross-borehole ERT
Hermans, Thomas ULg; Wildemeersch, Samuel ULg; Jamin, Pierre ULg et al

in Geothermics (2015), 53

The growing demand for renewable energy leads to an increase in the development of geothermal energy projects and heat has become a common tracer in hydrology and hydrogeology. Designing geothermal ... [more ▼]

The growing demand for renewable energy leads to an increase in the development of geothermal energy projects and heat has become a common tracer in hydrology and hydrogeology. Designing geothermal systems requires a multidisciplinary approach including geological and hydrogeological aspects. In this context, electrical resistivity tomography (ERT) can bring relevant, qualitative and quantitative information on the temperature distribution in operating shallow geothermal systems or during heat tracing experiments. We followed a heat tracing experiment in an alluvial aquifer using cross-borehole time-lapse ERT. Heated water was injected in a well while water of the aquifer was extracted at another well. An ERT section was set up across the main flow direction. The results of ERT were transformed into temperature using calibrated petrophysical relationships. These ERT-derived temperatures were then compared to direct temperature measurements in control piezometers collected with distributed temperature sensing (DTS) and groundwater temperature loggers. Spatially, it enabled to map the horizontal and vertical extent of the heated water plume, as well as the zones where maximum temperatures occurred. Quantitatively, the temperatures and breakthrough curves estimated from ERT were in good agreement with the ones observed directly during the rise and maximum of the curve. An overestimation, likely related to 3D effects, was observed for the tail of the heat breakthrough curve. The error made on temperature can be estimated to be between 10 to 20 %, which is a fair value for indirect measurements. From our data, we estimated a quantification threshold for temperature variation of 1.2°C. These results suggest that ERT should be considered when designing heat tracing experiments or geothermal systems. It could help also to assess the geometrical complexity of the concerned reservoirs. It also appears that ERT could be a useful tool to monitor and control geothermal systems once they are in operation. [less ▲]

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See detailUsing zero-inlated models to predict the relative distribution and abundance of roe deer over very large spatial scales
Bouyer, Yaëlle ULg; Rigot, Thibaud; Panzacchi, Manuela et al

in Annales Zoologici Fennici (2015), 52

In Norway, recovering populations of large carnivores commonly prey on roe deer (Capreolus capreolus). Understanding predator habitat use and ecology requires fine-scaled information on prey distribution ... [more ▼]

In Norway, recovering populations of large carnivores commonly prey on roe deer (Capreolus capreolus). Understanding predator habitat use and ecology requires fine-scaled information on prey distribution and abundance. However, the massive spatial scales at which large carnivores use the landscape presents many practical and statistical challenges for developing functional prey distribution models. Pellet-count data from >1000 km of transects gathered across southeastern Norway from 2005 to 2011 were used to derive a map of relative prey abundance for roe deer. These data were modeled using zero-inflated hurdle models using both environmental and anthropogenic variables. Snow depth and agricultural fields were the most significant variables in explaining both presence and abundance. Internal k-cross validation of the model showed medium accuracy (Spearman r = 0.35), whereas external evaluation carried out on the basis of independently collected snow-tracking data (Spearman r = 0.37) and hunting statistics (Spearman r = 0.88) showed high accuracy. The map generated can facilitate both the study of broad scale processes linking predators and prey as well as roe deer management in southeastern Norway. [less ▲]

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See detailIncentive salience attribution under reward uncertainty: A Pavlovian model
Anselme, Patrick ULg

in Behavioural Processes (2015), 111(1), 6-18

There is a vast literature on the behavioural effects of partial reinforcement in Pavlovian conditioning. Compared with animals receiving continuous reinforcement, partially rewarded animals typically ... [more ▼]

There is a vast literature on the behavioural effects of partial reinforcement in Pavlovian conditioning. Compared with animals receiving continuous reinforcement, partially rewarded animals typically show (a) a slower development of the conditioned response (CR) early in training and (b) a higher asymptotic level of the CR later in training. This phenomenon is known as the partial reinforcement acquisition effect (PRAE). Learning models of Pavlovian conditioning fail to account for it. In accordance with the incentive salience hypothesis, it is here argued that incentive motivation (or ‘wanting’) plays a more direct role in controlling behaviour than does learning, and reward uncertainty is shown to have an excitatory effect on incentive motivation. The psychological origin of that effect is discussed and a computational model integrating this new interpretation is developed. Many features of CRs under partial reinforcement emerge from this model. [less ▲]

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See detailSupervised inference of biological networks with trees : Application to genetic interactions in yeast
Schrynemackers, Marie ULg

Doctoral thesis (2015)

Networks or graphs provide a natural representation of molecular biology knowledge, in particular to model relationships between biological entities such as genes, proteins, drugs, or diseases. Because of ... [more ▼]

Networks or graphs provide a natural representation of molecular biology knowledge, in particular to model relationships between biological entities such as genes, proteins, drugs, or diseases. Because of the effort, the cost, or the lack of the experiments necessary to the elucidation of these networks, computational approaches for network inference have been frequently investigated in the literature. In this thesis, we focus on supervised network inference methods. These methods exploit supervised machine learning algorithms to train a model for identifying new interacting pairs of nodes from a training sample of known interacting and possibly non-interacting pairs and additional measurement data about the network nodes. Our contributions in this area are divided into three parts. First, the thesis examines the problem of the assessment of supervised network inference methods. Indeed, their reliable validation (in silico) poses a number of new challenges with respect to standard classification problems, related to the fact that pairs of objects are to be classified and to the specificities of biological networks. We perform a critical review and assessment of protocols and measures proposed in the literature. Through theoretical considerations and in silico experiments, we analyze in depth how important factors influence the outcome of performance estimation. These factors include the amount of information available for the interacting entities, the sparsity and topology of biological networks, and the lack of experimentally verified non-interacting pairs. From this analysis, we derived specific guidelines so as to how best exploit and evaluate machine learning techniques for network inference. Second, we systematically investigate, theoretically and empirically, the exploitation of tree- based methods for network inference. We consider these methods in the context of the two main generic classification-based approaches for network inference: the local approach, which trains a separate model for each network node, and the global approach, which trains a single model over pairs of nodes. We present and formalize these two approaches, extending the former for the prediction of interactions between two unseen network nodes, and discuss their specializations to tree-based methods, highlighting their interpretability and drawing links with clustering techniques. Extensive experiments are carried out with these methods on various biological networks that clearly highlight that these methods are competitive with existing methods. The interpretability of the resulting method family is illustrated on a drug-protein interaction network. In the last part of the thesis, we built on the experience gained in the two previous parts to try to predict at best the genetic interaction network in yeast S.cerevisiae. For that purpose, we collected a large dataset, assembling 4 millions gene pairs that were experimentally tested in the context of 11 different studies and 23 sets of measurements to use as gene input features for the inference. Through several cross-validation experiments on the resulting dataset, we showed that predicting genetic interactions is indeed possible to some useful extent and that actually in some settings, the accuracy of computational methods is not very far from that of experimental techniques. [less ▲]

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See detailValidation and test cases for a free surface PSH model
Goffin, Louis ULg; Erpicum, Sébastien ULg; Dewals, Benjamin ULg et al

in Advances in hydroinformatics - Simhydro 2014 (2015)

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See detailAn agent-based micro-simulation framework to assess the impact of river floods on transportation systems: implementation trajectory for an assessment in the Brussels metropolitan area
Saadi, Ismaïl ULg; Eftekhar, Hamed ULg; Mustafa, Ahmed et al

in International Journal for Traffic and Transport Engineering (IJTTE) Belgrade 2014 Proceedings (2015)

Several studies were made to assess the direct damage but few studies tackled the topic related to the assessment of indirect damage. This paper discusses the development of a large scale agent-based ... [more ▼]

Several studies were made to assess the direct damage but few studies tackled the topic related to the assessment of indirect damage. This paper discusses the development of a large scale agent-based micro-simulation framework to assess the economic damage caused by river floods. The advantage of this approach is that the economic loss can be assessed at individual level. For that purpose, relationship is established between costs and trips cancelation/duration growth. As the numerical simulations depend largely on the initial demand, the accuracy of the data is fundamental. The model is based upon several disaggregated data related to mobility behaviour of the Belgian citizens. The study area covers the Brussels metropolitan area which was subjected to several floods in the past and may see the risk increasing in the coming decades. [less ▲]

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See detailToward a Consistent Application of International Financial Reporting Standards (IFRSs) across Companies and Countries
Yammine, Mira ULg

Doctoral thesis (2014)

International Financial Reporting Standards (IFRSs) were developed to be a single set of high-quality globally accepted accounting standards. They are meant to allow uniformity in financial reporting ... [more ▼]

International Financial Reporting Standards (IFRSs) were developed to be a single set of high-quality globally accepted accounting standards. They are meant to allow uniformity in financial reporting, enhance comparability of financial statements in the midst of economical globalization, and allow companies with international subsidiaries to prepare their financial statements using similar global standards. The objective of the dissertation is to study whether the application of IFRSs is consistent across companies and countries; in particular we tackle the following two questions: -Does the application of IFRSs in the preparation of financial statements lead to consistency? -Does the public enforcement of accounting standards impact the consistent application of IFRSs? To answer the first question we have addressed standard IAS 36 that was developed by the International Accounting Standards Board (IASB) and covering impairment of assets. We found that managers’ opportunism still has an impact on the impairment of assets recognition and magnitude when taking impairment decisions. To address the second question, a survey covering enforcement of accounting standards activities was prepared and sent to public enforcement bodies in a number of countries mandating the adoption of IFRSs. The survey allowed us to construct an index that represents the activities of the public enforcement bodies. We studied the impact of public enforcement on specific applications of the standards, the results show a decrease in earnings management in countries with effective public enforcement. [less ▲]

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