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See detailGraded-commutative nonassociative algebras: higher octonions and Krichever-Novikov superalgebras; their structures, combinatorics and non-trivial cocycles.
Kreusch, Marie ULg

Doctoral thesis (2015)

This dissertation consists of two parts. The first one is the study of a series of real (resp. complex) noncommutative and nonassociative algebras $\bbO_{p,q}$ (resp. $\bbO_{n}$) generalizing the algebra ... [more ▼]

This dissertation consists of two parts. The first one is the study of a series of real (resp. complex) noncommutative and nonassociative algebras $\bbO_{p,q}$ (resp. $\bbO_{n}$) generalizing the algebra of octonion numbers $\bbO$. This generalization is similar to the one of the algebra of quaternion numbers in Clifford algebras. Introduced by Morier-Genoud and Ovsienko, these algebras have a natural $\bbZ_2^n$-grading ($p+q =n$), and they are characterized by a cubic form over the field $\bbZ_2.$ We establish all the possible isomorphisms between the algebras $\bbO_{p,q}$ preserving the structure of $\bbZ_2^n$-graded algebra. The classification table of $\bbO_{p,q}$ is quite similar to that of the real Clifford algebras $\cC l_{p,q}$, the main difference is that the algebras $\bbO_{n,0}$ and $\bbO_{0,n}$ are exceptional. We also provide a periodicity for the algebras $\bbO_n$ and $\bbO_{p,q}$ analogous to the periodicity for the Clifford algebras $\cC l_{n}$ and $\cC l_{p,q}$. In the second part we consider superalgebras of Krichever-Novikov (K-N) type. Krichever and Novikov introduced a family of Lie algebras with two marked points generalizing the Witt algebra and its central extension called the Virasoro algebra. The K-N Lie (super)algebras for more than two marked points were studied by Schlichenmaier. In particular, he extended the explicit formula of $2$-cocycles due to Krichever and Novikov to multiple-point situation. We give an explicit construction of central extensions of Lie superalgebras of K-N type and we establish a $1$-cocycle with values in its dual space. In the case of Jordan superalgebras related to superalgebras of K-N type, we calculate a 1-cocycle with coefficients in the dual space. [less ▲]

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See detailFictions du groupe littéraire
Saint-Amand, Denis ULg

Scientific conference (2015, April 17)

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See detailImpact of Aphasia on Consciousness Assessment: A Cross-Sectional Study.
Schnakers, C; Bessou, H; Rubi-Fessen, I et al

in Neurorehabilitation & Neural Repair (2015), 29

BACKGROUND: . Previous findings suggest that language disorders may occur in severely brain-injured patients and could interfere with behavioral assessments of consciousness. However, no study ... [more ▼]

BACKGROUND: . Previous findings suggest that language disorders may occur in severely brain-injured patients and could interfere with behavioral assessments of consciousness. However, no study investigated to what extent language impairment could affect patients' behavioral responses. OBJECTIVE: . To estimate the impact of receptive and/or productive language impairments on consciousness assessment. METHODS: . Twenty-four acute and subacute stroke patients with different types of aphasia (global, n = 11; Broca, n = 4; Wernicke, n = 3; anomic, n = 4; mixed, n = 2) were recruited in neurology and neurosurgery units as well as in rehabilitation centers. The Coma Recovery Scale-Revised (CRS-R) was administered. RESULTS: . We observed that 25% (6 out of 24) of stroke patients with a diagnosis of aphasia and 54% (6 out of 11) of patients with a diagnosis of global aphasia did not reach the maximal CRS-R total score of 23. An underestimation of the consciousness level was observed in 3 patients with global aphasia who could have been misdiagnosed as being in a minimally conscious state, even in the absence of any documented period of coma. More precisely, lower subscores were observed on the communication, motor, oromotor, and arousal subscales. CONCLUSION: . Consciousness assessment may be complicated by the co-occurrence of severe language deficits. This stresses the importance of developing new tools or identifying items in existing scales, which may allow the detection of language impairment in severely brain-injured patients. [less ▲]

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See detailVariogram-based inversion of time-lapse electrical resistivity data: development and application to a thermal tracing experiment
Hermans, Thomas ULg; Nguyen, Frédéric ULg

Poster (2015, April 15)

Electrical resistivity tomography (ERT) has become a popular imaging methodology in a broad range of applications given its large sensitivity to subsurface parameters and its relative simplicity to ... [more ▼]

Electrical resistivity tomography (ERT) has become a popular imaging methodology in a broad range of applications given its large sensitivity to subsurface parameters and its relative simplicity to implement. More particularly, time-lapse ERT is now increasingly used for monitoring purposes in many contexts such as water content, permafrost, landslide, seawater intrusion, solute transport or heat transport experiments. Specific inversion schemes have been developed for time-lapse data sets. However, in contrast with static inversions for which many techniques including geostatistical, minimum support or structural inversion are commonly applied, most of the methodologies for time-lapse inversion still rely on non-physically based spatial and/or temporal smoothing of the parameters or parameter changes. In this work, we propose a time-lapse ERT inversion scheme based on the difference inversion scheme. We replace the standard smoothness-constraint regularization operator by the parameter change covariance matrix. This operator takes into account the correlation between changes in resistivity at different locations through a variogram computed using independent data (e.g., electromagnetic logs). It may vary for subsequent time-steps if the correlation length is time-dependent. The methodology is first validated and compared to the standard smoothness-constraint inversion using a synthetic benchmark simulating the injection of a conductive tracer into a homogeneous aquifer inducing changes in resistivity values of known correlation length. We analyze the influence of the assumed correlation length on inversion results. Globally, the method yields better results than the traditional smoothness constraint inversion. Even if a wrong correlation length is assumed, the method performs as well as the smoothness constraint since the regularization operator balances the weight given to the model constraint functional in the objective function. Then the methodology is successfully applied to a heat injection and pumping experiment in an alluvial aquifer. The comparison with direct measurements in boreholes (temperature loggers and distributed temperature sensing optic fibres) shows that ERT-derived temperatures and breakthrough curves image reliably the heat plume through time (increasing part of the curve, maximum and tail are correctly retrieved) and space (lateral variations of temperature are observed) with less spatial smoothing than standard methods. The development of new regularization operators for time-lapse inversion of ERT data is necessary given the broad range of applications where ERT monitoring is used. In many studies, independent data are available to derive geostatistical parameters that can be subsequently used to regularize geophysical inversions. In the future, the integration of spatio-temporal variograms into existing 4D inversion schemes should further improve ERT time-lapse imaging. [less ▲]

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See detailRegularized focusing inversion of time-lapse electrical resistivity data: an approach to parametrize the minimum gradient support functional
Nguyen, Frédéric ULg; Hermans, Thomas ULg

Poster (2015, April 15)

Inversion of time-lapse resistivity data allows obtaining ‘snapshots’ of changes occurring in monitored systems for applications such as aquifer storage, geothermal heat exchange, site remediation or ... [more ▼]

Inversion of time-lapse resistivity data allows obtaining ‘snapshots’ of changes occurring in monitored systems for applications such as aquifer storage, geothermal heat exchange, site remediation or tracer tests. Based on these snapshots, one can infer qualitative information on the location and morphology of changes occurring in the subsurface but also quantitative estimates on the degree of changes in certain property such as temperature or total dissolved solid content. Analysis of these changes can provide direct insight into flow and transport and associated processes and controlling parameters. However, the reliability of the analysis is dependent on survey geometry, measurement schemes, data error, and regularization. Survey design parameters may be optimized prior to the monitoring survey. Regularization, on the other hand, may be chosen depending on available information collected during the monitoring. Common approaches consider smoothing model changes both in space and time but it is often needed to obtain a sharp temporal anomaly, for example in fractured aquifers. We here propose to use the alternative regularization approach based on minimum gradient support (MGS) (Zhdanov, 2002) for time-lapse surveys which will focus the changes in tomograms snapshots. MGS will limit the occurrences of changes in electrical resistivity but will also restrict the variations of these changes inside the different zones. A common difficulty encountered by practitioners in this type of regularization is the choice of an additional parameter, the so-called , required to define the MGS functional. To the best of our knowledge, there is no commonly accepted or standard methodology to optimize the MGS parameter . The inversion algorithm used in this study is CRTomo (Kemna 2000). It uses a Gauss-Newton scheme to iteratively minimize an objective function which consists of a data misfit functional and a model constraint functional. A univariate line search is performed at each Gauss-Newton iteration step to find the optimum value of the regularization parameter  which minimizes the data misfit as a function of  while the data misfit is above the desired value and yields the desired target misfit (root-mean square value of error-weighted data misfit equal to 1) at the last iteration for a maximum value of . We propose here to optimize the  of the MGS functional by considering a univariate line search at the first iteration to find the  that minimizes the data misfit. The parameter is then kept constant during the Gauss-Newton iterative scheme. In this contribution, we validate our approach on a numerical benchmark and apply it successfully on a case study in the context of salt tracers in fractured aquifers. Zhdanov M.S. 2002. Geophysical Inverse Theory and Regularization Problems. Elsevier, Amsterdam, 628 p. Kemna A. 2000. Tomographic Inversion of Complex Resistivity - Theory and Application. PhD Thesis, Ruhr University Bochum. [less ▲]

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See detailLight, alertness, cognition, and much more
Vandewalle, Gilles ULg

Scientific conference (2015, April 13)

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See detailUncoupled and coupled hydrogeophysical inversions of seawater intrusion and geothermal hydrologic models
Beaujean, Jean ULg

Doctoral thesis (2015)

Most of humans live in coastal and alluvial plains. Sustainable water supply systems are essential for drinking water production while long-term groundwater access ensures its geothermal use. Owing to ... [more ▼]

Most of humans live in coastal and alluvial plains. Sustainable water supply systems are essential for drinking water production while long-term groundwater access ensures its geothermal use. Owing to climate change and anthropogenic activities, groundwater resources will be increasingly threatened throughout the twenty-first century. In the context of over-development, any effort to overcome groundwater mining at the expense of better understanding groundwater management problems may be misguided. A combination of robust measuring technologies and reliable predictions based on numerical models are necessary to estimate better hydrogeological parameters. Sparse and continuous data are increasingly being used conjunctively in hydrogeological modeling and inverse calibration to alleviate extrapolation and subjective interpretation. In hydrogeology, electrical resistivity tomography (ERT) gives quantitative and qualitative information on salinity and temperature distribution. ERT offers a means for mapping the subsurface hydrogeological structures and the hydrologic process dynamics in both space and time. The integration of ERT data to hydrogeological calibration is particularly suited to define the hydrogeological models quantitatively and qualitatively. In a deterministic framework, hydrogeophysical inversion methods may be particularly useful for predictive analysis and assessment of groundwater pre-emptive management strategies. This work focuses on calibrating physically-based and spatially distributed groundwater flow and transport models with non-to minimally invasive electrical tomography. The general objective is to provide better estimates of hydrogeological parameters on two relevant problems: seawater intrusion in coastal areas and geothermal energy in shallow environments. We compare methods to integrate quantitatively ERT data, possibly other hydrologic or geological data, with existing information to hydrogeological models. Two hydrogeophysical inversion schemes are developped and a thorough comparison of an uncoupled and a coupled quantitative approach based on the use of surface ERT only is performed. The uncoupled hydrogeophysical inversion involves constraining hydraulic parameters using geophysically-derived data and first requires a geophysical inversion, after which the geophysical parameters are converted to hydrologic data through a petrophysical relationship. The inverse hydrological calibration is then performed on these inferred hydrological data. The coupled hydrogeophysical inversion involves constraining hydraulic parameters using geophysical data through a forward hydrogeophysical model in which the hydrologic data are converted to resistivities through a petrophysical relationship. A geophysical forward problem is then solved for the geophysical data. The inverse hydrological calibration is performed on the inferred geophysical observations. In both schemes, we show that an independent geophysical inversion is required to delineate heterogeneous bodies. In this context, we study how to derive informative content of ERT images and therefore ERTderived hydrologic data and ERT-derived geometry. We show that a quantitative appraisal (the cumulative sensitivity) must be used as a proxy for filtering areas correctly resolved. Our developments are demonstrated on several benchmark SWI models (numerical and analytical), a thermohydrologic model and a field test. We show that the reliability of estimated SWI model parameters with the uncoupled approach depends on ERT image appraisal, on geophysical data collection strategy and hydrogeological model conceptualization. The ERT image appraisal plays a key role in retrieving high quality ERT-derived data and helps discriminate different measurement arrays. It is particularly useful in preventing the integration of noise-related artefacts in the conceptualization. We endeavor to quantify the modeling error by a thorough comparison of different strategies to assess the effect of decreasing model conceptual errors to hydrogeological calibration. In the SWI analytical models, we highlight the subjectivity of the uncoupled approach due to the nature of the required hydrologic data (sharp interface). We demonstrate that the conjunctive use of an image appraisal tool with the well-known Ghyben-Herzberg solution is needed to infer reliable ERT-derived observation data. We further demonstrate that a SWI analytical solution may be used to calibrate an equivalent hydraulic parameter based on an ERT dataset generated from a density-dependent groundwater flow model. In the thermohydrologic model, we show that the effectiveness of the uncoupled scheme in calibrating heat transport parameters may be hampered due to the regularization constraint in the geophysical inversion. We demonstrate the importance of a noise level-related filter on the time-lapse ERT images aimed at properly quantifying the spatio-temporal ERTderived temperature changes. We also advocate the use of a physically-based constraint on the ERT-derived temperatures to account for spatial mixing of waters and to cope indirectly with the smoothing effect in the ERT images. In each application, the coupled approach significantly prevails over the uncoupled scheme in terms of reliability of the parameter estimates when no model conceptual error exists. [less ▲]

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See detailDispositifs de conservation écorégionale et droits indigènes dans l’Amazonie Bolivienne: Les cas des Peuples du Madidi et Pilón Lajas
Marquez Guerra, José Francisco ULg

Doctoral thesis (2015)

The apparatus of conservation at the ecoregional scale integrating natural landscape and cultural landscapes in the Amazon basin has been introduced by international conservation NGOs since the beginning ... [more ▼]

The apparatus of conservation at the ecoregional scale integrating natural landscape and cultural landscapes in the Amazon basin has been introduced by international conservation NGOs since the beginning of the 90s when the term hotspot was invented to designate the importance of "mega-diversity "of tropical forests for the survival of humanity. The representation of environmental problems in the Amazon region as serious threats to life on the planet entered the political agenda of the international community becoming a matter of priority attention. To find solutions to this expanding threat, scientists, activists and interested parties have reflected on some formulas, innovative programs and strategies in order that cooperation and international aid could favor the action of effective conservation and sustainable development. The problem of resource degradation of biodiversity, and the loss of the values of cultural diversity of Amazonian peoples is since then conceived as a challenge that goes beyond national political interests, becoming a global issue. Bolivia was a breeding ground for these pioneering efforts, they have made a pragmatic view of international aid with new tools and effective techniques to combat emerging threats, one of them are financial mechanisms for conservation planning. These have entered the Bolivian legal system from the 80 which coincides with the modernization of the state, an ambitious development plan supported by the implementation of neoliberal measures to promote economic growth, administrative decentralization as a new form to exercise power by delegating powers to the departmental and municipal levels, popular participation, as legitimacy methodology, defining local actors and regional planning policy as a useful management of natural resources for sustainable development. International actors of conservation, a group of scientific elite and environmental activists in the country and leaders of local indigenous movements have played an important role before and after this neoliberal modernization in the implementation of an ecorregional conservation apparatus in the Bolivian Amazon. The objective of this transdisciplinaria research, is an ethnographic description, based on the theoretical and methodological repertoire of legal anthropology and sociology of ANT Translation, of how the practices and strategies of conservation at the ecoregional scale through its technical, financial and legal instruments configure the territories, affect social relations and transform representations and practices of the nature of Amazonian peoples Mosetene, Tsimane' Tacana, Quechua-Tacana and Leco. The traditional spaces of these peoples are in total or partially overlapping with the current Natural Park and Integrated Management Area Madidi and Biosphere Reserve and Indigenous Territory Pilón Lajas implemented as protected areas during the 90 In this context, challenges and current controversies looming over the planning and use of space at different scales between actors of the policies of sustainable development and conservation, local political elites and indigenous peoples. [less ▲]

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See detailMeasuring and modelling the intra-day variability of the CO2 & CO2 vertical soil profile production in a Scots pine forest
Longdoz, Bernard; Goffin, Stéphanie; Parent, Florian et al

in Geophysical Research Abstracts (2015, April), 17

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See detailThe CROSTVOC project – an integrated approach to study the effect of stress on BVOC exchange between agricultural crops and grassland ecosystems and the atmosphere
Amelynck, Crist; Heinesch, Bernard ULg; Aubinet, Marc ULg et al

in Geophysical Research Abstracts (2015, April), 17

Global changes in atmospheric composition and climate are expected to affect BVOC exchange between terrestrial vegetation and the atmosphere through changes in the drivers of constitutive BVOC emissions ... [more ▼]

Global changes in atmospheric composition and climate are expected to affect BVOC exchange between terrestrial vegetation and the atmosphere through changes in the drivers of constitutive BVOC emissions and by increases in frequency and intensity of biotic or abiotic stress episodes. Indeed, several studies indicate changes in the emission patterns of constitutive BVOCs and emission of stress-induced BVOCs following heat, drought and oxidative stress, amongst others. Relating changes in BVOC emissions to the occurrence of one or multiple stressors in natural environmental conditions is not straightforward and only few field studies have dealt with it, especially for agricultural crop and grassland ecosystems. The CROSTVOC project aims to contribute in filling this knowledge gap in three ways. Firstly, it aims at performing long-term BVOC emission field measurements from maize (Zea mays L.) and wheat (Triticum aestivum L.), two important crop species on the global scale, and from grassland. This should lead to a better characterization of (mainly oxygenated) BVOC emissions from these understudied ecosystems, allowing a better representation of those emissions in air quality and atmospheric chemistry and transport models. BVOC fluxes are obtained by the Disjunct Eddy Covariance by mass scanning (DEC-MS) technique, using a hs-PTR-MS instrument for BVOC analysis. Secondly, the eddy covariance BVOC flux measurements (especially at the grassland site) will be accompanied by ozone flux, chlorophyll fluorescence, photosynthesis and soil moisture measurements, amongst others, to allow linking alterations in BVOC emissions to stress episodes. Simultaneously, automated dynamic enclosures will be deployed in order to detect specific abiotic and biotic stress markers by PTR-MS and identify them unambiguously by GC-MS. Thirdly, the field measurements will be accompanied by laboratory BVOC flux measurements in an environmental chamber in order to better disentangle the responses of the BVOC emissions to driving factors that co-occur in field conditions and to determine the influence of single abiotic stressors on BVOC emissions. Next to a general presentation, some preliminary results of the project will be shown. [less ▲]

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See detailImproving energy partitioning and the nighttime energy balance by implementation of a multi-layer energy budget in ORCHIDEE-CAN
Chen, Yiying; Ryder, James; Naudts, Kim et al

in Geophysical Research Abstracts (2015, April), 17

Canopy structure is one of the most important vegetation characteristics for land-atmosphere interactions as it determines the energy and scalar exchanges between land surface and overlay air mass. In ... [more ▼]

Canopy structure is one of the most important vegetation characteristics for land-atmosphere interactions as it determines the energy and scalar exchanges between land surface and overlay air mass. In this study we evaluated the performance of a newly developed multi-layer energy budget (Ryder et al., 2014) in a land surface model, ORCHIDEE-CAN (Naudts et al., 2014), which simulates canopy structure and can be coupled to an atmospheric model using an implicit procedure. Furthermore, a vertical discrete drag parametrization scheme was also incorporated into this model, in order to obtain a better description of the sub-canopy wind profile simulation. Site level datasets, including the top-of-the-canopy and sub-canopy observations made available from eight flux observation sites, were collected in order to conduct this evaluation. The geo-location of the collected observation sites crossed climate zones from temperate to boreal and the vegetation types included deciduous, evergreen broad leaved and evergreen needle leaved forest with maximum LAI ranging from 2.1 to 7.0. First, we used long-term top-of-the-canopy measurements to analyze the performance of the current one-layer energy budget in ORCHIDEE-CAN. Three major processes were identified for improvement through the implementation of a multi-layer energy budget: 1) night time radiation balance, 2) energy partitioning during winter and 3) prediction of the ground heat flux. Short-term sub-canopy observations were used to calibrate the parameters in sub-canopy radiation, turbulence and resistances modules with an automatic tuning process following the maximum gradient of the user-defined objective function. The multi-layer model is able to capture the dynamic of sub-canopy turbulence, temperature and energy fluxes with imposed LAI profile and optimized parameter set at a site level calibration. The simulation result shows the improvement both on the nighttime energy balance and energy partitioning during winter and presents a better Taylor skill score, compared to the result from single layer simulation. The importance of using the multi-layer energy budget in a land surface model for coupling to the atmospheric model will also be discussed in this presentation. [less ▲]

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See detailModelling carbon fluxes of forest and grassland ecosystems in Western Europe using the CARAIB dynamic vegetation model: evaluation against eddy covariance data.
Henrot, Alexandra-Jane ULg; François, Louis ULg; Dury, Marie ULg et al

in Geophysical Research Abstracts (2015, April), 17

Eddy covariance measurements are an essential resource to understand how ecosystem carbon fluxes react in response to climate change, and to help to evaluate and validate the performance of land surface ... [more ▼]

Eddy covariance measurements are an essential resource to understand how ecosystem carbon fluxes react in response to climate change, and to help to evaluate and validate the performance of land surface and vegetation models at regional and global scale. In the framework of the MASC project (« Modelling and Assessing Surface Change impacts on Belgian and Western European climate »), vegetation dynamics and carbon fluxes of forest and grassland ecosystems simulated by the CARAIB dynamic vegetation model (Dury et al., iForest - Biogeosciences and Forestry, 4:82-99, 2011) are evaluated and validated by comparison of the model predictions with eddy covariance data. Here carbon fluxes (e.g. net ecosystem exchange (NEE), gross primary productivity (GPP), and ecosystem respiration (RECO)) and evapotranspiration (ET) simulated with the CARAIB model are compared with the fluxes measured at several eddy covariance flux tower sites in Belgium and Western Europe, chosen from the FLUXNET global network (http://fluxnet.ornl.gov/). CARAIB is forced either with surface atmospheric variables derived from the global CRU climatology, or with in situ meteorological data. Several tree (e.g. Pinus sylvestris, Fagus sylvatica, Picea abies) and grass species (e.g. Poaceae, Asteraceae) are simulated, depending on the species encountered on the studied sites. The aim of our work is to assess the model ability to reproduce the daily, seasonal and interannual variablility of carbon fluxes and the carbon dynamics of forest and grassland ecosystems in Belgium and Western Europe. [less ▲]

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See detailAnisotropy and tension-compression asymmetry modeling of the room temperature plastic response of Ti-6A1-4V
Tuninetti, Victor; Gilles, Gaëtan ULg; Pardoen, Thomas et al

in International Journal of Plasticity (2015), 67

The mechanical behavior of the alloy Ti-6A1-4V is characterized using uniaxial tension, uniaxial compression, simple shear and place strain tests in three orthogonal material directions. The experimental ... [more ▼]

The mechanical behavior of the alloy Ti-6A1-4V is characterized using uniaxial tension, uniaxial compression, simple shear and place strain tests in three orthogonal material directions. The experimental results reveal tension/compression asymmetry, anisotropic yielding and anisotropic strain-hardening. These features are incorporated into an elasto-plastic constitutive law based on the macroscopic orthotropic yield criterion "CPB06" adapted to hexagonal metals. A new identification method for the yield criterion parameters is proposed by inverse modeling of the axial strain field compression specimens in the three orthogonal directions of the material. The sensitivity of different sets of material parameters to the identification method is also analysed and the capacity of the model to accurately predict the forces and displacement field is discussed. A validation of the best set of identified CPB06material parameters is performed by comparing the load-displacement curves in different loading directions for tensile tests on notched round bars with different levels of stress triaxiality and for compression tests on elliptical cross-section specimens, both tests involving multiaxial strain fields and large deformations. [less ▲]

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See detailTracking Middleboxes in the Mobile World with TraceboxAndroid
Thirion, Valentin; Edeline, Korian ULg; Donnet, Benoît ULg

in 7th International Workshop on Traffic Monitoring and Analysis (TMA) (2015, April)

Middleboxes are largely deployed over cellular networks. It is known that they might disrupt network performance, expose users to security issues, and harm protocols deployability. Further, hardly any ... [more ▼]

Middleboxes are largely deployed over cellular networks. It is known that they might disrupt network performance, expose users to security issues, and harm protocols deployability. Further, hardly any network measurements tools for smartphones are able to infer middlebox behaviors, specially if one cannot control both ends of a path. In this paper, we present TraceboxAndroid a proof-of-concept measurement application for Android mobile devices implementing the tracebox algorithm. It aims at diagnosing middlebox-impaired paths by detecting and locating rewriting middleboxes. We analyze a dataset sample to highlight the range of opportunities offered by TraceboxAndroid. We show that TraceboxAndroid can be useful for mobile users as well as for the research community. [less ▲]

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See detailThe words of prevention, part II: ten terms in the realm of quaternary prevention
Jamoulle, Marc ULg; Gavilan, Enrique; Cardoso, Raquel Val et al

in Revista Brasileira de Medicina de Família e Comunidade (2015)

ABSTRACT Objective: This part II article about the ‘words of prevention’ presents in a terminological way the content of ten current concepts used in the prevention domain which are closely linked to ... [more ▼]

ABSTRACT Objective: This part II article about the ‘words of prevention’ presents in a terminological way the content of ten current concepts used in the prevention domain which are closely linked to quaternary prevention: (1) overinformation, (2) overdiagnosis, (3) medically unexplained symptoms, (4) overmedicalisation, (5) incidentaloma, (6) overscreening, (7) overtreatment, (8) shared decision making, (9) deprescribing, and (10) disease mongering. Methods: with the support of the laboratory team of the University of Rouen, France, which is dedicated to medical terminology and semantic relationships, it was possible to utilize a graphic user interface (called DBGUI) allowing the construction of links for each of chosen terms, and making automatic links to MeSH, if any. Those concepts are analyzed in their environment in current literature, as well as in their MeSH counterparts, if any, and related semantic online terminologies. Results and Discussion: The rules in terminological development aspire to cover the whole field of a concept and in the meantime, it helps to avoid the noise due to proxy and not exactly related issues. This refers to exhaustivity and specificity in information retrieval. Our finds show that referring to MeSH only in information retrieval in General Practice/Family medicine can induce much noise and poor adequacy to the subject investigated. Conclusion: Gathering concepts in specially prepared terminologies for further development of ontologies is a necessity to enter in the semantic web area and the era of distributed data. [less ▲]

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See detailThe words of prevention, part I: changing the model
Jamoulle, Marc ULg; Gavilan, Enrique; Cardoso, Raquel Val et al

in Revista Brasileira de Medicina de Família e Comunidade (2015)

ABSTRACT Objective: This part I article explores the different meanings of relevant keywords for General Practice/Family Medicine (GP/FM) in the prevention domain. The aim is to contribute to information ... [more ▼]

ABSTRACT Objective: This part I article explores the different meanings of relevant keywords for General Practice/Family Medicine (GP/FM) in the prevention domain. The aim is to contribute to information process in GP/FM by keeping in line with the main terms used in health care organization. Methods: Important keywords for GP/FM in the prevention domain were selected. Then, a search was carried out on the main sources in GP/FM databases, as well as in Medical Subject Heading and major terminological databases available online. Results and Discussion: There is discrepancy between the conceptual contents of major prevention models amongst the usual bibliographic sources of knowledge in GP/FM in particular and medicine in general. Conclusion: For GP/FM, distribution of preventive activities is now firmly established on a new constructivist model, privileging the doctor-patient relationships and introducing a cybernetic thinking on the health care activities with a special commitment to ethics and the positive duty of beneficence. [less ▲]

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