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See detailTechno-economic optimization of isolate micro-grids including PV and Li-Ion Batteries in the Bolivian context
Balderrama, Sergio; Canedo, Walter; Lemort, Vincent ULg et al

in Proceedings of ECOS 2016 - the 29th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems (2016)

In Bolivia 44 % of the people living in rural areas do not have reliable access to electric energy. This is due to a combination of unfavourable geography and the lack of economic resources to achieve the ... [more ▼]

In Bolivia 44 % of the people living in rural areas do not have reliable access to electric energy. This is due to a combination of unfavourable geography and the lack of economic resources to achieve the necessary infrastructure. In this context, the main goal of this study is to evaluate the economic and technical feasibility of micro-grids including photovoltaic panels (PV), batteries systems and the possible inclusion of diesel generators for off-grid applications. To that aim, a linear optimization model was developed within the Pyomo framework in order to optimize both the installed capacities and dispatch of the PV, battery and diesel sub-systems. The defined objective function is the net present cost. The exogenous inputs of the optimization are the typical demand and solar irradiation of a region of Bolivia in order to achieve results close to real Bolivian systems. Results indicate that due to the high levels of subvention to hydrocarbons, the PV and Li-Ion technology are not yet competitive with a diesel generator for the electrification of rural areas. On the other hand a sensitivity analysis is performed and proves that if the government decide to stop part of the subvention or shared it between conventional and non-conventional sources, the PV becomes competitive and the Li-Ion batteries enter the market around 2020. [less ▲]

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See detailNutrition du brûlé grave.
ROUSSEAU, Anne-Françoise ULg; Cynober, Luc; Berger, Mette M.

in Quilliot, Didier; Thibault, Ronan; Bachmann, Patrick (Eds.) et al Traité de nutrition clinique. (2016)

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See detailMigration in the Western Mediterranean: Space, Mobility and Borders
Bernes, Laure-Anne; Bousetta, Hassan ULg; Zickgraf, Caroline ULg

Book published by Routledge (2016)

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See detailMon enfant bégaie : Que faire ?
Leclercq, Anne-Lise ULg

Conference given outside the academic context (2016)

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See detailElectrophoretic deposition of hydroxyapatite and hydroxyapatite– alginate on rapid prototyped 3D Ti6Al4V scaffolds
Ozhukil Kollath, Vinayaraj; Chen, Qiang; Mullens, Steven et al

in Journal of Materials Science (2016), 51

The advantage of using bioceramic particles coated on porous three-dimensional structures is still unexplored in the purpose of improving the osteoinduction of hybrid metallic scaffold implants in vivo ... [more ▼]

The advantage of using bioceramic particles coated on porous three-dimensional structures is still unexplored in the purpose of improving the osteoinduction of hybrid metallic scaffold implants in vivo. In this study, we evaluate electrophoretic deposition (EPD) to coat porous Ti6Al4V scaffolds with hydroxyapatite (HA). Scaffolds were shaped in different open structures with a horizontal shift in fiber stacking. They were produced using three-dimensional fiber deposition method and were coated by EPD with HA powder (d10 = 1.7, d50 = 5.7 and d90 = 18 lm) suspended in ethanol or butanol at different concentration, DC voltage, and time. A composite HA–alginate was also used to coat the scaffolds. Alginate was used as a binder, and the coating properties (homogeneity, thickness, cracks, continuity, etc.) were compared to coatings obtained from pure HA suspensions. Voltage and time of deposition effects were studied between 10 and 140 V and 10 and 120 s, respectively. Coating thickness and density with respect to the depth of the porous structure were studied by observing cross sections using scanning electron microscopy and image processing analysis. HA–alginate combination resulted in a homogeneous and deeper dense layer of HA. This work also points to the characteristics of HA–alginate composite as a superior alternative to pure HA coating which needs an appropriate thermal treatment for adequate substrate adhesion. [less ▲]

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See detailShear Response of Prestressed Thin-Webbed Continuous Girders
Collins, Michael; Xie, Liping; Mihaylov, Boyan ULg et al

in ACI Structural Journal (2016)

While different design codes provide similar guidance for the flexural design of prestressed thin: webbed continuous girders, the shear design provisions differ greatly. This paper investigates these ... [more ▼]

While different design codes provide similar guidance for the flexural design of prestressed thin: webbed continuous girders, the shear design provisions differ greatly. This paper investigates these discrepancies with the help of eleven experiments and a number of analytical studies. Together these provide the basis for recommendations for engineers conducting the shear design for new girders or evaluating the shear capacity of existing girders. It is shown that the traditional ACI approach of taking Vc as the smaller of Vci, flexural:shear cracking load, and Vcw, web:shear cracking load, can significantly overestimate the shear strength of such girders particularly if they are highly prestressed and contain relatively small quantities of shear reinforcement. The other codes evaluated provided more conservative predictions. It is shown that the ACI predictions can be improved significantly by taking into account the effect of flexural stresses on web shear cracking. While the ACI code uses different shear strength equations for members subjected to external axial loads versus members subjected to internal prestressing forces, the studies summarized in this paper support the idea that unification of these ACI shear provisions is possible. [less ▲]

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See detailHow do cumulative live birth rates and cumulative multiple live birth rates over complete courses of assisted reproductive technology treatment per woman compare among registries?
De Neubourg, Diane; Bogaerts, Kris; Blockeel, Christophe et al

in Human Reproduction (2016)

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See detailBode, Nicolai und Elisa von der Recke: Korrespondenzen und Netzwerke
Leyh, Valérie ULg

in Kinzel, Till; Berghahn, Cord-Friedrich (Eds.) Johann Joachim Christoph Bode (1731-1793) - ein Aufklärer aus Braunschweig in den kulturellen Netzwerken seiner Zeit (2016)

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See detailLes frontières du droit à l'épreuve des films de mafias
Thirion, Nicolas ULg; Pasteger, David ULg

in Flores-Lonjou, Magalie (Ed.) Frontière(s) au cinéma - Actes des septièmes rencontres "Droit et cinéma" (2016)

demander dans quelle mesure l’injonction du brigand qui exige « la bourse ou la vie ! » peut être comparée à la norme de comportement édictée par un Etat sous la forme d’une loi, c’est poser la ... [more ▼]

demander dans quelle mesure l’injonction du brigand qui exige « la bourse ou la vie ! » peut être comparée à la norme de comportement édictée par un Etat sous la forme d’une loi, c’est poser la sempiternelle question de la frontière qui sépare le droit du non-droit, tout au moins dans une perspective juspositiviste, en tant que cette école de théorie du droit refuse de définir le phénomène juridique en se référant à une valeur ou un ensemble de valeurs. La frontière du droit et du non-droit est en effet particulièrement difficile à tracer, nonobstant plusieurs siècles de discussions philosophiques à ce sujet. Lorsque, fatigué de parcourir les chemins, le brigand décide de s’installer en ville pour s’y adonner au racket des commerçants du quartier et qu’il s’adjoint ensuite le concours d’autres bandits, c’est un gang de malfaiteurs qui voit le jour. Si, ultérieurement, ce gang se concerte avec d’autres bandes de truands pour s’épauler mutuellement dans les exactions auxquelles ils se livrent sur leurs territoires respectifs, il prend alors la forme d’une organisation criminelle ou, au sens large du terme, d’une « mafia ». Le cinéma de Francis Ford Coppola, Martin Scorsese, Brian De Palma, Sergio Leone ou bien encore Matteo Garrone, entre autres, dépeint, souvent avec réalisme, la genèse et le fonctionnement de telles organisations criminelles. La communication a proposé, au moyen d’illustrations tirées des films de ces grands cinéastes, une analyse de microscopie juridique du crime organisé. Une description serrée de la particule élémentaire du phénomène juridique, identifiée par Lucien François dans son ouvrage de théorie du droit Le cap des Tempêtes sous l’appellation de « jurème », met en lumière une indéniable proximité entre les techniques de pouvoir utilisées respectivement par le brigand isolé, la bande organisée et l’Etat souverain. En remontant ensuite vers la structure plus complexe d’un système étatique, on se demandera si, en fin de compte, dans la vision juspositiviste poussée au bout de sa logique par Lucien François, l’Etat ne pourrait être réduit, d’un point de vue ontologique, à un pouvoir de fait comparable, par les techniques de contrainte qu’il exerce sur ses sujets, à une organisation criminelle – abstraction faite des valeurs promues ou poursuivies par tel ou tel appareil étatique. [less ▲]

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See detailBehaviour of composite joints under combined bending moments and axial loads - Deliverable D.9 - Robustimpact
D'Antimo, Marina ULg; Demonceau, Jean-François ULg; Jaspart, Jean-Pierre ULg

Report (2016)

The present work is dedicated to the behaviour of composite joints under combined bending moments and axial loads. The results presented in this part have been mainly developed in [1]. The component ... [more ▼]

The present work is dedicated to the behaviour of composite joints under combined bending moments and axial loads. The results presented in this part have been mainly developed in [1]. The component method is a nowadays widely recognized procedure for the evaluation of the design properties of structural joints. It is used as a reference method in the Eurocodes and the proposed rules in these codes are mainly devoted to the characterization of joints subjected to bending moments and shear forces. However, in some situations, these joints can be subjected to combined axial loads and bending moments, for instance in frames subjected to an exceptional event leading to the loss of a column, situation where significant tying forces can developed in the structural beams above the lost column. The purpose of this work is to present and validate a design model, founded on the component method, aiming at predicting the behaviour of composite joints subjected to combined axial loads and bending moments. In particular, in the following the validation of this model through comparisons to recent experimental tests performed on steel composite beam-to-column joints at University of Stuttgart will be presented. The proposed method is mainly adapted from the former research work of Demonceau [2]. Some changes are made in order to improve the former method and also to extend it to the type of joints used in the framework of the current European project (Deliverable 5). Beam to column composite joints with flush-end-plate connection are mainly investigated hereinafter. The work will manly focus on the behaviour of joints under sagging moments, as it has not been widely researched yet in comparison to joints under hogging moment. An excel-based routine of the proposed method has been developed; it has been designed to be adaptable to different types of composite joints, with the objective to facilitate the verification and/or the application of the above-mentioned design model. [less ▲]

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See detailNonparametric control charts: economic statistical design
Marcos Alvarez, Alejandro ULg; Heuchenne, Cédric ULg; Faraz, Alireza ULg

E-print/Working paper (2016)

This paper studies economic statistical designs (ESD) for nonparametric control charts based on the sign and Wilcoxon tests. The main advantage of the procedures is that, except for the tested location ... [more ▼]

This paper studies economic statistical designs (ESD) for nonparametric control charts based on the sign and Wilcoxon tests. The main advantage of the procedures is that, except for the tested location parameter, they do not use either any parametric distribution for the quality characteristic or any information about the possible involved parameters, neither in the in-control nor in the out-of-control state. This is made possible by minimizing a cost function specified independently of these quantities. Unlike the ESD for the $\overline{x}$ chart, the resulting charts designs are robust to changes of the distributions of the observations (in control or out of control), provide reliable statistical guarantees when the $\overline{x}$ chart ESD does not and stay competitive even when the strong assumptions of the $\overline{x}$ chart ESD are fully satisfied. These new techniques can therefore be applied to a definitely wider class of problems and their designs may stay constant over time without losing performance. [less ▲]

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See detailIdentifying mismatch between urban travel demand and transport network services using GPS data: A case study in the fast growing Chinese city of Harbin
Cui, JianXun; Liu, Feng; Hu, Jia et al

in Neurocomputing (2016), 181

The world's urban population growth and economic development have led to the reshaping of metropolitan space layouts among residential, employment and shopping locations, generating growing mismatch ... [more ▼]

The world's urban population growth and economic development have led to the reshaping of metropolitan space layouts among residential, employment and shopping locations, generating growing mismatch between travel demand and transport services. A reliable method to accurately analyze mobility demand and underlying transport network systems and to identify areas with serious mismatch problems is important for the design of effective policy measures. In this paper, we make use of the wide deployment of GPS devices in vehicles in many cities today, to develop such a method. This approach is developed using GPS data collected from all taxis operating in the Chinese city of Harbin between July and September in 2013. It consists of four major steps. First, city-wide mobility patterns are modeled based on GPS trajectories. This model captures a set of key traffic characteristics for each pair of regions in the entire urban network, including travel demand, travel speed and route directness of travel paths. From this model, a set of indicators is then built to measure the road transport performance between the regions, and the areas with serious mismatch problems are subsequently pinpointed. Finally, the identified problematic regions are further examined and specific transport problems are analyzed. By applying the proposed method to the city of Harbin, the potential and effectiveness of this method are demonstrated. Moreover, with more and more urban vehicles being equipped with GPS devices, the designed method can be easily transferred to other cities, thus paving a way for the adoption of the presented approach for an up-to-date and spatial-temporal sensitive road network analysis approach that supports the establishment of a more sustainable urban transport system. [less ▲]

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See detailLéon d’Oultres
Marchandisse, Alain ULg

in Lecocq, Isabelle (Ed.) Les vitraux de la cathédrale Saint-Paul à Liège (2016)

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See detailArt. Liège et la Guerre de Cent Ans
Marchandisse, Alain ULg

in Moeglin, Jean-Marie (Ed.) Dictionnaire Guerre de Cent Ans (2016)

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See detailSPICAM observations and modeling of Mars aurorae
Soret, Lauriane ULg; Gérard, Jean-Claude ULg; Libert, Ludivine ULg et al

in Icarus (2016), 264

Martian aurorae have been detected with the SPICAM instrument on board Mars Express both in the nadir and the limb viewing modes. In this study, we focus on three limb observations to determine both the ... [more ▼]

Martian aurorae have been detected with the SPICAM instrument on board Mars Express both in the nadir and the limb viewing modes. In this study, we focus on three limb observations to determine both the altitudes and the intensities of the auroral emissions. The CO (a3P–X1R) Cameron bands between 190 and 270 nm, the CO Fourth Positive system (CO 4P) between 135 and 170 nm, the CO2+ doublet at 289 nm, the OI at 297.2 nm and the 130.4 nm OI triplet emissions have been identified in the spectra and in the time variations of the signals. The intensities of these auroral emissions have been quantified and the altitude of the strongest emission of the CO Cameron bands has been estimated to be 137 ± 27 km. The locations of these auroral events have also been determined and correspond to the statistical boundary of open-closed magnetic field lines, in cusp-like structures. The observed altitudes of the auroral emissions are reproduced by a Monte-Carlo model of electron transport in the Martian thermosphere for mono-energetic electrons between 40 and 200 eV. No correlation between electron fluxes measured in the upper thermosphere and nadir auroral intensity has been found. Here, we simulate auroral emissions observed both at the limb and at the nadir using electron energy spectra simultaneously measured with the ASPERA-3/ELS instrument. The simulated altitudes are in very good agreement with the observations. We find that predicted vertically integrated intensities for the various auroral emissions are overestimated, probably as a consequence of the inclination and curvature of the magnetic field line threading the aurora. However, the relative brightness of the CO and CO2+ emissions is in good agreement with the observations. [less ▲]

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See detailRisk assessment of soil compaction in the Walloon region in Belgium
D'Or, Dimitri; Destain, Marie-France ULg

in Mathematical Geosciences (2016)

It is well known that soil compaction affects root growth and disrupts the activity of soil microfauna and microorganisms, resulting in yield loss. With the more intensive use of heavy machines in ... [more ▼]

It is well known that soil compaction affects root growth and disrupts the activity of soil microfauna and microorganisms, resulting in yield loss. With the more intensive use of heavy machines in agriculture and forestry, the risk of soil compaction is increasing. In this study, precompression stress (Pc) was chosen as an indicator of the susceptibility of soils to compaction and was calculated using pedotransfer functions (PTFs). PTFs involve eight variables related to the hydraulic and mechanical behaviour of soils: organic matter content; bulk density; air capacity; available water capacity; non-plant available water capacity; saturated hydraulic conductivity; cohesion; and angle of internal friction. Combining these PTFs with geostatistics and Monte Carlo simulations, Pc maps were produced at the regional scale for Wallonia in Belgium, accompanied by uncertainty quantification maps. These maps were then used to produce compaction risk maps based on common scenarios. The results showed that the modal Pc map was coherent with the spatial distribution of the main variables, namely soil texture and organic matter content. The risk maps enabled areas with a compaction risk in both agricultural and forestry contexts to be identified. These maps could be useful in drawing up soil protection measures and policies. [less ▲]

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See detailBi-objective Road and Pipe Network Design for Crude Oil Transport in the Sfax Region in Tunisia
Belaid, Emna ULg; Limbourg, Sabine ULg; Mostert, Martine ULg et al

in Procedia Engineering (2016), 142

In this paper, we examine a bi-objective road and pipe network design for crude oil transport in the Sfax region in Tunisia. In particular, we search for the minimum spanning trees (MST) that connect the ... [more ▼]

In this paper, we examine a bi-objective road and pipe network design for crude oil transport in the Sfax region in Tunisia. In particular, we search for the minimum spanning trees (MST) that connect the different oil fields with the port of La Skhirra. In the determination of the minimum spanning trees, two objectives are taken into account, i.e. accident risk and construction costs. By using an improved ɛ-constraint resolution technique, the Pareto optimal combinations of risk and cost are found. Results indicate that the network solutions by pipe outperform the solutions by road. When the minimum spanning trees for the two extremes on the Pareto curves, i.e. the cost minimum and risk minimum, are compared, one could note considerable differences in the links that form the MST. This implies that policy makers have an important role in deliberating between costs and risks. [less ▲]

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See detailL’impact des activités non agricoles sur la pauvreté et l’inégalité rurales dans les groupements Bugorhe et Irhambi-Katana (Territoire de Kabare, Province du Sud-Kivu)
Furaha Mirindi, Germaine ULg; Namegabe Mastaki, Jean Luc; Lebailly, Philippe ULg

in JOURNAL OF ORIENTAL AND AFRICAN STUDIES (2016), 25

Using a survey on the socio-economic situation of households in 2012, the study analyses the effect of non farm income on inequality and poverty alleviation in a rural area of the Democratic Republic of ... [more ▼]

Using a survey on the socio-economic situation of households in 2012, the study analyses the effect of non farm income on inequality and poverty alleviation in a rural area of the Democratic Republic of Congo, by comparing a group of households practicing agriculture only and another group which combines agriculture and nonfarm activities. The approach used considers non farm income as an exogenous transfer which completes the whole household income, and analyses the contribution of different sources of income on the inequality in using the Gini index. The results show that inequality increases when a segment of the population does not have access to non-agricultural income. In this case, non farm income is not a substitute of farm income, rather the complement. The poverty analysis is based on the Congolese rural threshold poverty in terms of basic needs to calculate the rate, depth and severity of poverty indexes in using of Foster- Greer-Thorbecke. The results show that households practicing agriculture only are poorer. [less ▲]

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See detailFree public transport: A socio-cognitive analysis
Cools, Mario ULg; Fabbro, Yannick; Bellemans, Tom

in Transportation Research. Part A : Policy & Practice (2016), 86

In this study, the modal shift potential of introducing a free alternative (free public transportation) and of changing the relative prices of transportation is examined. The influence of a cognitive ... [more ▼]

In this study, the modal shift potential of introducing a free alternative (free public transportation) and of changing the relative prices of transportation is examined. The influence of a cognitive analysis on the zero-price effect is also analyzed. The data used for the analysis stem from a stated preference survey with a sample of approximately 670 respondents that was conducted in Flanders, Belgium. The data are analyzed using a mixed logit model. The modeling results yield findings that confirm the existence of a zero-price effect in transport, which is in line with the literature. This zero-price effect is increased by the forced cognitive analysis for shopping trips, although not for work/school or recreational trips. The results also demonstrate the importance of the current mode choice in hypothetical mode choices and the importance of car availability. The influence of changing relative prices on the modal shift is found to be insignificant. This might be partially because the price differences were too small to matter. Hence, an increase in public transport use can be facilitated by the introduction of free public transport, particularly when individuals evaluate the different alternatives in a more cognitive manner. These findings should be useful to policy makers evaluating free public transport and considering how best to target and promote relevant policy. [less ▲]

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