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See detailAn economic case for transnational and international transmission
Ernst, Damien ULg

Speech/Talk (2015)

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See detailRecent ethane increase above North America: comparison between FTIR measurements and model simulations
Franco, Bruno ULg; Bader, Whitney ULg; Mahieu, Emmanuel ULg et al

Conference (2015, June 11)

Ethane (C2H6) has a large impact on tropospheric composition and air quality because of its involvement in the global VOC (volatile organic compound) – HOx – NOx chemistry responsible for generating and ... [more ▼]

Ethane (C2H6) has a large impact on tropospheric composition and air quality because of its involvement in the global VOC (volatile organic compound) – HOx – NOx chemistry responsible for generating and destroying tropospheric ozone. By acting as a major sink for tropospheric OH radicals, the abundance of C2H6 influences the atmospheric content of carbon monoxide and impacts the lifetime of methane. Moreover, it is an important source of PAN, a thermally unstable reservoir for NOx radicals. On a global scale, the main sources of C2H6 are leakage from the production, transport of natural gas loss, biofuel consumption and biomass burning, mainly located in the Northern Hemisphere. Due to its relatively long lifetime of approximately two months, C2H6 is a sensitive indicator of tropospheric pollution and transport. Using an optimized retrieval strategy (see Franco et al., 2014), we present here a 20-year long-term time series of C2H6 column abundance retrieved from ground-based Fourier Transform InfraRed (FTIR) solar spectra recorded from 1994 onwards at the high-altitude station of Jungfraujoch (Swiss Alps, 46.5° N, 3580 m a.s.l.), part of the Network for the Detection of Atmospheric Composition Change (NDACC, see http://www.ndacc.org). After a regular 1994 – 2008 decrease of the C2H6 amounts, which is very consistent with prior major studies (e.g., Aydin et al., 2011; Simpson et al., 2012) and our understanding of global C2H6 emissions, trend analysis using a bootstrap resampling tool reveals a C2H6 upturn and a statistically-significant sharp burden increase from 2009 onwards (Franco et al., 2014). We hypothesize that this observed recent increase in C2H6 could affect the whole Northern Hemisphere and may be related to the recent massive growth in the exploitation of shale gas and tight oil reservoirs. This hypothesis is supported by measurements derived from solar occultation observations performed since 2004 by the Atmospheric Chemistry Experiment – Fourier Transform Spectrometer (ACE-FTS) instrument and at other NDACC sites, namely Toronto (44° N) and Thule (77° N). Indeed, the recent rates of changes characterizing these data sets are consistent in magnitude and sign with the one derived from the FTIR measurements at Jungfraujoch. In contrast, the ethane time series form Lauder (45° S) shows a monotonic decrease over the last two decades. Investigating both the cause and impact on air quality of the C2H6 upturn should be a high priority for the atmospheric chemistry community. [less ▲]

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See detailA semiquantitative framework for gene regulatory networks: increasing the time and quantitative resolution of Boolean networks
Kerkhofs, Johan ULg; Geris, Liesbet ULg

in PLoS ONE (2015), 10(6), 0130033

Boolean models have been instrumental in predicting general features of gene networks and more recently also as explorative tools in specific biological applications. In this study we introduce a basic ... [more ▼]

Boolean models have been instrumental in predicting general features of gene networks and more recently also as explorative tools in specific biological applications. In this study we introduce a basic quantitative and a limited time resolution to a discrete (Boolean) framework. Quantitative resolution is improved through the employ of normalized variables in unison with an additive approach. Increased time resolution stems from the introduction of two distinct priority classes. Through the implementation of a previously published chondrocyte network and T helper cell network, we show that this addition of quantitative and time resolution broadens the scope of biological behaviour that can be captured by the models. Specifically, the quantitative resolution readily allows models to discern qualitative differences in dosage response to growth factors. The limited time resolution, in turn, can influence the reachability of attractors, delineating the likely long term system behaviour. Importantly, the information required for implementation of these features, such as the nature of an interaction, is typically obtainable from the literature. Nonetheless, a trade-off is always present between additional computational cost of this approach and the likelihood of extending the model’s scope. Indeed, in some cases the inclusion of these features does not yield additional insight. This framework, incorporating increased and readily available time and semi-quantitative resolution, can help in substantiating the litmus test of dynamics for gene networks, firstly by excluding unlikely dynamics and secondly by refining falsifiable predictions on qualitative behaviour. [less ▲]

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See detailImpact of Different Thermal Comfort Models on Zero Energy Residential Buildings in Hot Climate
Attia, Shady ULg; Carlucci, Salvatore

in Energy & Buildings (2015)

The selection of a thermal comfort model for establishing indoor optimal hygrothermal conditions during the hot period has a major impact on energy consumption of Net Zero Energy Buildings in hot climates ... [more ▼]

The selection of a thermal comfort model for establishing indoor optimal hygrothermal conditions during the hot period has a major impact on energy consumption of Net Zero Energy Buildings in hot climates. The objective of this paper is to compare the influence of using different thermal comfort models for zero energy buildings in hot climates. The paper compares the impact of applying Fanger’s model, Givoni’s model, the ASHRAE 55 adaptive comfort model and the EN 15251 adaptive comfort model on energy consumption and comfort performance. Using both the building performance simulation tools ZEBO and EnergyPlus for energy simulation, an existing prototype of a residential apartment module is used to evaluate energy performance and thermal comfort in two parametric series. The first one is the result of coupling natural ventilation and mechanical cooling and the second one is guided coupling natural ventilation, mechanical cooling and ceiling fans. This study shows that the percentage of energy consumption difference meeting the comfort criteria according to ISO 7730 in comparison to EN 15251, ASHRAE 55 or Givoni’s model varied up to 16%, 21% and 24.7% respectively for the presented case study. More energy savings can be expected for buildings in hot climates with greater cooling demands. [less ▲]

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See detailCharacterizing the morphology of suburban settlements: a method based on a semi-automatic classification of building clusters
de Smet, Fabian; Teller, Jacques ULg

in Landscape Research (2015)

Urban sprawl is transforming our landscapes and rural areas at a spectacular pace. Measuring the strength of the phenomenon and proposing dynamic ways to delineate suburban areas have been the object of ... [more ▼]

Urban sprawl is transforming our landscapes and rural areas at a spectacular pace. Measuring the strength of the phenomenon and proposing dynamic ways to delineate suburban areas have been the object of much debate amongst scientists. The present article takes the view that, beyond measuring and delineating suburban areas, more efforts should be directed to qualifying the morphology of built settlements within these areas. Therefore it proposes a method based on a semi-automatic classification system of building clusters, designed to describe and interpret the phenomenon from a morphological perspective. This method is based on a combination of field surveys with numerical analyses of digital land cadastre maps. The application of this classification system to the suburban area around Liege reveals that, far from developing in a complete indifference of local conditions, contemporary suburban settlements are influenced by landscape structures inherited from the past. [less ▲]

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See detailRegional crop and irrigation monitoring: some examples of (new) opportunities
Wellens, Joost ULg

in Begian workshop: Space4Food (2015, June 11)

Satellite images are used since long for agricultural monitoring at different spatial scales: from continental, national to regional and even field level. Combined with agro-meteorological data and ... [more ▼]

Satellite images are used since long for agricultural monitoring at different spatial scales: from continental, national to regional and even field level. Combined with agro-meteorological data and simulation models they constitute powerful decision support tools for agriculture throughout the world. Some examples at different scales and domains are presented. In Burkina Faso, free MODIS time series of coarse resolution vegetation indices (NDVI), phenological and meteorological data are combined in a multiple regression analysis for early yield warning in the cotton industry. Using a limited amount of data, it allows a decent yield forecasting more than a month before harvest. Time series of ERS radar images are analysed to monitor water intakes on the irrigated perimeter of Tadla (Morocco). The back-scatter intensity gives a clear indication of the top soil moisture state, permitting irrigation managers a regional monitoring of the irrigation water distribution and a guidance in the water allocation pricing. Actually in Belgium, and soon to be exported elsewhere, very-high resolution imagery (SPOT-5 Take5) are used to observe crop canopy development (fAPAR, fCover) on field level. Either by curve-fitting functions or assimilating these satellite derived data in existing crop growth models, improved and spatially more detailed forecasting systems are being developed. Although mostly still in the domain of applied research, the new availability of high spatial and temporal resolution imageries such those that will provide the Sentinel satellites paves the way to a growing number of operational end users. [less ▲]

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See detailarchiDART: Plant Root System Architecture Analysis Using DART and RSML Files
Delory, Benjamin ULg; Baudson, Caroline ULg; Brostaux, Yves ULg et al

Computer development (2015)

Analysis of complex plant root system architectures (RSA) using the output files created by Data Analysis of Root Tracings (DART), an open-access software dedicated to the study of plant root architecture ... [more ▼]

Analysis of complex plant root system architectures (RSA) using the output files created by Data Analysis of Root Tracings (DART), an open-access software dedicated to the study of plant root architecture and development across time series (Le Bot et al (2010) DART: a software to analyse root system architecture and development from captured images, Plant and Soil, 326, 261--273), and RSA data encoded with the Root System Markup Language (RSML) (Lobet et al (2015) Root System Markup Language: Toward a Unified Root Architecture Description Language, Plant Physiology, 167, 617--627). [less ▲]

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See detailStatistical analysis and multi-instrument overview of the quasi-periodic 1-hour pulsations in the Saturn's outer magnetosphere
Palmaerts, Benjamin ULg; Roussos, Elias; Krupp, Norbert et al

Conference (2015, June 05)

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See detailTSP model for electric vehicle deliveries, considering speed, loading and road grades
Bay, Maud ULg; Limbourg, Sabine ULg

Conference (2015, June 05)

The objective usually considered in sustainable transportation is to minimize pollution due to emissions, and equivalently energy consumption. Turning to electric mobility, pollution is related to ... [more ▼]

The objective usually considered in sustainable transportation is to minimize pollution due to emissions, and equivalently energy consumption. Turning to electric mobility, pollution is related to electricity production technology, not considered in this research; driving range is the major concern nowadays, due to the limited capacity of batteries and long recharge times . Maximizing the driving range or the level of energy (state of charge of the battery) at destination leads to consider the main factors of energy consumption which are : vehicle weight, engine efficiency and consumption models, drive speed and acceleration, drive pattern, road grade, and payload. We define the electric vehicle travelling salesman problem (EV-TSP) and the electric vehicle routing problem (E-VRP) based on the classical TSP and on the Pollution Routing Problem (PRP) and present models and preliminary results for those problems. [less ▲]

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See detailUse and utility of combined solute and heat tracer tests for characterizing hydrogeothermal properties of an alluvial aquifer
Klepikova, Maria; Wildemeersch, Samuel; Jamin, Pierre ULg et al

Conference (2015, June 05)

Using heat as a tracer together with a solute tracer is interesting for characterizing hydrogeothermal properties of the underground. These properties are particularly needed to dimension any low ... [more ▼]

Using heat as a tracer together with a solute tracer is interesting for characterizing hydrogeothermal properties of the underground. These properties are particularly needed to dimension any low temperature geothermal project using an open doublet system (pumping-reinjection) in a shallow aquifer. The tracing experiment, conducted in the alluvial aquifer of the River Meuse (Hermalle near Liège), consisted in injecting simultaneously heated water at 40°C and a dye tracer in a piezometer and monitoring the evolution of temperature and tracer concentration in the recovery well and in nine monitoring piezometers located in three transects with regards to the main groundwater flow direction. The breakthrough curves measured in the recovery well showed that heat transfer in the alluvial aquifer is slower. All measured results show also that the heat diffusivity is larger than the solute dispersion. These contrasted behaviours are stressed in the lower permeability zones of the aquifer. Inverse modelling is applied for calibrating the numerical simulation of the groundwater flow, heat and solute transport. First results are presented showing that the density effect must be taken into account and that, as expected, the most important parameter to be calibrated accurately is the hydraulic conductivity. [less ▲]

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See detailENMG du pied
WANG, François-Charles ULg

Conference (2015, June 05)

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See detailStrategy for financing foundations: how do they create value?
Mernier, Amélie ULg

Conference (2015, June 05)

Traditionally, the research on strategy has rather focused on profit-seeking organizations whose primary objective is to generate revenues through the price mechanism. Nevertheless, all organizations ... [more ▼]

Traditionally, the research on strategy has rather focused on profit-seeking organizations whose primary objective is to generate revenues through the price mechanism. Nevertheless, all organizations benefit from developing a strategic approach (Moore 2000). This paper focuses on financing foundations, non-profit organizations that are private, non-membership based, self-governing and serving a public purpose (Anheier 2001) and that make grants, give loans or hold equity. The core activity of a financing foundation is to finance operating intermediaries, for example non-profit association, NGOs or social enterprises, which will then implement projects and programs directly in line with the mission of the financing foundation. During the last decades, these organizations have made a breakthrough by establishing themselves as private actors that will look after the public interest. For long, strategic thinking has been impeded in foundations because the essence of the philanthropic action was giving without any expectation in terms of social impact. Today, the legitimacy of these organizations is challenged and there is a stronger demand for efficiency reinforced by the emergence of a new philanthropy inspired by corporate management principles (e.g. venture philanthropy considered as the more advocated strategic approach (Gautier et Pache 2014) ) and the question of strategy really matters. This paper aims at designing a conceptual strategic framework for financing foundations whose ultimate goal is to create value for society. To justify the development of a specific strategic framework for financing foundations, I first compare financing foundations with other financing organization according to six dimensions: ultimate goal, sources of resources, nature of the contribution, means, logic of action and accountability. Then, I review the academic literature in the field of philanthropy having a strategy focus in order to highlight the current gaps in the literature. Only few authors give a comprehensive view of the strategic question for this type of organization. Existing papers focus only on fragments of strategy and tackle two strategic issues: the mission statement and the evaluation. The decision-making processes by which the initial objectives are achieved are ignored; the strategic choices which philanthropic organizations make to fulfill their mission have not yet been identified. Based on the identification of key strategic commitments (in terms of scope and mechanisms) underlying the implementation of the predefined social mission and two crucial trade-offs (impact expectation and level of mission objectivity), the strategic dimensions of a financing foundations, leading to value creation for the society, are conceptualized. Two processes of value creation are distinguished: direct and indirect value creation. The course of actions chosen by a financing foundation is closely connected to its ultimate goal that is, increase the utility of a target group of beneficiaries (i.e. direct value creation). In addition, even if the very objective of the financing foundation is not to increase the utility of its donors and founders, it is effectively what happens (i.e. indirect value creation). The empirical research that will be conducted based on the strategic conceptual framework is then described and additional research questions are highlighted. [less ▲]

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See detailL'entrepreneuriat dans le secteur des biotechnologies: les clés du succès dans un contexte de mondialisation
Kamdem, Irenée ULg

Conference (2015, June 03)

Cette communication est réalisée dans le cadre du doctorat. Son principal objectif a été de présenter aux créateurs d'entreprises du secteur des biotechnologies, les outils stratégiques de gestion et ... [more ▼]

Cette communication est réalisée dans le cadre du doctorat. Son principal objectif a été de présenter aux créateurs d'entreprises du secteur des biotechnologies, les outils stratégiques de gestion et management dans un environnement qui se mondialise davantage. Ces créateurs sont généralement dotés de grandes qualités scientifiques et techniques mais possèdent moins de qualités managériales. La maîtrise des notions entrepreneuriales leur permettra de mieux gérer et contrôler leurs entreprises. [less ▲]

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See detailThe nonlinear piezoelectric tuned vibration absorber
Soltani, Payam ULg; Kerschen, Gaëtan ULg

Scientific conference (2015, June 03)

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See detailConnecting planets to their moons: The auroral satellite footprints
Bonfond, Bertrand ULg

Conference (2015, June 03)

Among the many features of the Giant planets’ aurorae are very special spots which move in a very distinct manner compared with the remaining of the aurora. Indeed, these spots are magnetically connected ... [more ▼]

Among the many features of the Giant planets’ aurorae are very special spots which move in a very distinct manner compared with the remaining of the aurora. Indeed, these spots are magnetically connected with planetary satellites and rotate around the poles at the same pace as their parent moon. These features, called the satellite footprints, are the signature of the electromagnetic interaction between the moons and the rapidly rotating magnetosphere plasma. On Jupiter, Io, Europa and Ganymede (and possibly Callisto) have their respective footprints while only the Enceladus footprint has been detected on Saturn so far. Several models of the interaction between Io and the jovian magnetosphere, from the unipolar inductor to the ideal Alfvén wings model, have been proposed well before the first observations of the footprints in 1993. However, the continuously improving technologies and observing methods gave rise to more accurate observations that challenged several aspects of these models and lead to further refinements. For example, when analyzed in detail, high resolution images of the aurorae show that the footprints of Io and Ganymede are not made of one, but several spots, and that the footprint of Io, Europa and Ganymede can be followed by an extended tail. The respective motion of these spots as a function of the orientation of the planetary magnetic field suggests that the Alfvén waves launched from these satellites accelerate the electrons in both directions along the field lines, hence doubling the number of visible spots, Moreover, studies of the satellite footprints are not only useful to unveil some key aspects of the moon-magnetosphere interactions, but they also contribute to the understanding of the whole magnetospheric system. For instance, their locations have been used as landmarks to constrain magnetic field models or to more accurately relate some auroral structures with their root region in the magnetosphere. [less ▲]

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See detailLe Grap 3a au Niger
Andres, Ludovic ULg; Lebailly, Philippe ULg

Scientific conference (2015, June 03)

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See detailModélisation de la remontée des eaux dans les anciennes mines de charbon : un outil pour détecter les seuils de risques d’inondation en plaine alluviale de la Meuse près de Liège (Belgique)
Dassargues, Alain ULg; Wildemeersch, Samuel; Orban, Philippe ULg et al

in Des villes et des territoires sobres et sûrs, Synthèse des interventions (2015, June 03)

La plaine alluviale de la Meuse occupe la partie centrale du bassin charbonnier de Liège. Durant les exploitations minières, les niveaux d’eau des aquifères avaient été rabattus par des pompages d’exhaure ... [more ▼]

La plaine alluviale de la Meuse occupe la partie centrale du bassin charbonnier de Liège. Durant les exploitations minières, les niveaux d’eau des aquifères avaient été rabattus par des pompages d’exhaure. Des galeries d’exhaure creusées à partir des pieds de versant dans la vallée de la Meuse contribuaient également à dénoyer le gisement. La fermeture des dernières exploitations minières durant les années 70 et 80 a été le plus souvent assortie d’un arrêt des opérations de pompage qui y sont associées. Ceci a induit une remontée significative des eaux souterraines avec des conséquences indésirables possibles. Les modèles hydrogéologiques peuvent grandement aider à simuler les écoulements des eaux souterraines dans le contexte particulier des travaux miniers. Cependant, les techniques de modélisation classiques ne sont pas adaptées à ce contexte car le milieu est fortement perturbé par les anciens travaux et les réseaux de galeries. Par conséquent, des techniques de modélisation spécifiques ont été développées. Il s'agit d'une combinaison de modèles de boîte (ne nécessitant que quelques paramètres) pour calculer les niveaux d'eau moyens dans les zones exploitées, avec une modélisation physiquement basée et spatialement distribuée représentant explicitement les zones inexploitées et prenant en compte les interactions entre ces deux sous-domaines. Grâce à ce couplage, les échanges d'eau entre les zones exploitées et inexploitées sont explicitement pris en compte. La méthode permet de simuler la remontée des eaux souterraines après la fermeture des mines et des phénomènes associés tels que les 'coups d'eau' produits par les galeries drainantes. Les concepts et équations de la méthode sont présentés et illustrés sur des cas synthétiques, puis sur l'application de la zone de Cheratte-Blégny. [less ▲]

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See detail« Prof d’EPS » un métier qui bouge
Cloes, Marc ULg

Conference (2015, June 03)

Since the beginning of the 3rd millenium, the focus of the physical educaiton course evolved a lot, as well as the expected role of the teachers. In fact, the priority given to the teaching of sport ... [more ▼]

Since the beginning of the 3rd millenium, the focus of the physical educaiton course evolved a lot, as well as the expected role of the teachers. In fact, the priority given to the teaching of sport skills progressively moved to the preparation of physically educated citizen. In parallel, School being considered as one of the main pilar of the fight against sedentariness and promotion of an active lifestyle, PE teachers are more and more presented as the responsables of the coordination of such actions within their schools. It means that they have to envisage to adapt their representations and professional decisions. The goal of this presentation is to stimulate the awareness and to illustrate courses of action likely to incitate pratitioners to engage themselves in a reviewing process. [less ▲]

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