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See detailMeasuring the effect of amantadine in chronic anoxic minimally conscious state.
Schnakers, Caroline ULg; Hustinx, Roland ULg; Vandewalle, Gilles ULg et al

in Journal of Neurology, Neurosurgery & Psychiatry (2008), 79(2), 225-7

Detailed reference viewed: 46 (6 ULg)
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See detailMeasuring the Effect of Stochastic Perturbation Component in Cellular Automata Urban Growth Model
El Saeid Mustafa, Ahmed Mohamed ULg; Saadi, Ismaïl ULg; Cools, Mario ULg et al

in Procedia Environmental Sciences (2014), 22(Winter), 156168

Urban environments are complex dynamic systems whose prediction of the future states cannot exclusively rely on deterministic rules. Although several studies on urban growth were carried out using ... [more ▼]

Urban environments are complex dynamic systems whose prediction of the future states cannot exclusively rely on deterministic rules. Although several studies on urban growth were carried out using different modelling approaches, the measurement of uncertainties was commonly neglected in these studies. This paper investigates the effect of uncertainty in urban growth models by introducing a stochastic perturbation method. A cellular automaton is used to simulate predicted urban growth. The effect of stochastic perturbation is addressed by comparing series of urban growth simulations based on different degree of stochastic perturbation randomness with the original urban growth simulation, obtained with the sole cellular automata neighbouring effects. These simulations are evaluated using cell-to-cell location agreement and a number of spatial metrics. The model framework has been applied to the Ourthe river basin in Belgium. The results show that the accuracy of the model is increased by introducing a stochastic perturbation component with a limited degree of randomness, in the cellular automata urban growth model. [less ▲]

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See detailMeasuring the equivalence of item difficulty in the various versions of an international test
Grisay, Aletta; Monseur, Christian ULg

in Studies in Educational Evaluation (2007), 33(1), 69-86

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See detailMeasuring the extent of linkage disequilibrium in commercial pig populations
Harmegnies, N.; Farnir, Frédéric ULg; DAVIN, Fabienne ULg et al

in Animal Genetics (2006), 37(3), 225-231

To evaluate the extent of linkage disequilibrium in domestic pigs, we genotyped 33 and 44 unrelated individuals from two commercial populations for 29 and five microsatellite markers located on ... [more ▼]

To evaluate the extent of linkage disequilibrium in domestic pigs, we genotyped 33 and 44 unrelated individuals from two commercial populations for 29 and five microsatellite markers located on chromosomes 15 and 2 respectively. A high proportion of marker pairs up to 40 cM apart exhibited significant linkage disequilibrium in both populations. Pair-wise r(2) values averaged between 0.15 and 0.50 (depending on chromosome and population) for markers < 1 cM apart and declined to values of 0.05 for more distant syntenic markers. Our results suggest that both populations underwent a bottleneck approximately 20 generations ago, which reduced the effective population size from thousands to < 200 animals. [less ▲]

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See detailMeasuring the flowing properties of powders and grains
Lumay, Geoffroy ULg; Boschini, Frédéric ULg; traina, Karl et al

in Powder Technology (2012), 224

A granular material is a complex system which exhibits non-trivial transitions between the static, the quasi-static and the dynamical states. Indeed, an assembly of grains can behave like a solid or a ... [more ▼]

A granular material is a complex system which exhibits non-trivial transitions between the static, the quasi-static and the dynamical states. Indeed, an assembly of grains can behave like a solid or a fluid according to the applied stress. In between solid and fluid granular states, very slow dynamics are observed. When a complete macroscopic characterization of a powder is needed, all these granular states have to be precisely analyzed. In this paper, we show how three measurement techniques can be used to measure the physical properties of a powder. The measurements are based on classical tests modified to meet the recent fundamental researches on granular materials. The static properties of the powder are analyzed through the shape of a heap. The quasi-static behavior is studied with the analysis of the compaction dynamics. Finally, the dynamical regime is monitored through the flow in a rotating drum. In order to illustrate how these measurements can be used in practical cases, analyses are performed with three types of granular materials: silicon carbide abrasives, flours and rice. These selected materials allow to show the influence of the different parameters (grain size, grain size distribution, grain shape) on the macroscopic properties of the assembly. Moreover, these studies show the pertinence of the parameters obtained with the proposed techniques for the rheological characterization of powders and grains. [less ▲]

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See detailMeasuring the general phytosanitary situation: development of a plant health barometer
Wilmart, Olivier; Van Huffel, X.; Diricks, H. et al

Poster (2014)

Objective: measuring and monitoring the yearly evolution of the general plant health (phytosanitary situation) of plants and plant products in Belgium in an objective manner, and communicating about it in ... [more ▼]

Objective: measuring and monitoring the yearly evolution of the general plant health (phytosanitary situation) of plants and plant products in Belgium in an objective manner, and communicating about it in a comprehensive way. [less ▲]

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See detailMeasuring the general phytosanitary situation: development of a plant health barometer
Wilmart, Olivier; Van Huffel, Xavier; Diricks, Herman et al

in European Journal of Plant Pathology (2014), Online First Articles

The development of a plant health barometer, an instrument to measure the general phytosanitary situation on a national level (Belgium) and on a yearly basis and to monitor its evolution over time, is ... [more ▼]

The development of a plant health barometer, an instrument to measure the general phytosanitary situation on a national level (Belgium) and on a yearly basis and to monitor its evolution over time, is described. The elaboration of a set of 13 plant health indicators (PHI’s) as the basis for the plant health barometer is discussed. These indicators were weighted by experts - including scientists, policy makers and agroindustrial representatives - to determine their relative impact in the barometer. The result of the barometer is expressed as a comparison with the previous year. Based on the results of the 13 PHI’s, it is concluded that the general plant health in Belgium shows a positive evolution from 2007 until 2010 and a negative evolution from 2010 until 2012. The plant health barometer provides a overview of the phytosanitary situation of plants and plant products in Belgium and is a tool to communicate in an intelligible, comprehensible manner on aspects of plant health to consumers and professional stakeholders in the plant production chain. Together with the food safety barometer and the animal health barometer, the plant health barometer is one of the three instruments to provide a overview on the general status of the safety of the food chain in Belgium. [less ▲]

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See detailMeasuring the importance of competition: a new formulation of the problem
Damgaard, Christian; Fayolle, Adeline ULg

in Journal of Ecology (2010), (98), 1-6

1. Currently, there is a debate among plant ecologists on the concepts of the intensity of competition and the importance of competition, which is central to many issues of modern plant population ecology ... [more ▼]

1. Currently, there is a debate among plant ecologists on the concepts of the intensity of competition and the importance of competition, which is central to many issues of modern plant population ecology and plant community ecology. 2. It is problematic that the current measures of intensity and importance of competition, typically, are reported as dimensionless indices because they hide the fact that both indices are functions of plant density and the level of the environmental gradient. 3. Here, a new formulation of the concepts is suggested, which explicitly highlights the functional dependencies on plant density and the level of the environmental gradient. The new measures are a generalization of the previous indices and correspond to the previous indices in the case of a simple experimental design. 4. The suggested measures of the intensity and importance of competition are exemplified using data from a response surface competition experiment between Agrostis capillaris and Festuca ovina along a herbicide gradient, where the expected clear effect of plant density was demonstrated. 5. Synthesis. As the suggested measures of the intensity and importance of competition explicitly highlight the functional dependencies on plant density and the level of the environmental gradient, we think that they will help to ensure a closer connection between experimental plant ecology and the attempts to model plant populations and communities. [less ▲]

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See detailMeasuring the Influence of the kth Largest Variable on Functions over the Unit Hypercube
Marichal, Jean-Luc; Mathonet, Pierre ULg

in Modeling Decisions for Artificial Intelligence 7th International Conference, MDAI 2010 (2010)

By considering a least squares approximation of a given square integrable function f: [0,1]^n\to R by a shifted L-statistic function (a shifted linear combination of order statistics), we define an index ... [more ▼]

By considering a least squares approximation of a given square integrable function f: [0,1]^n\to R by a shifted L-statistic function (a shifted linear combination of order statistics), we define an index which measures the global influence of the k-th largest variable on f. We show that this influence index has appealing properties and we interpret it as an average value of the difference quotient of f in the direction of the k-th largest variable or, under certain natural conditions on f, as an average value of the derivative of f in the direction of the k-th largest variable. We also discuss a few applications of this index in statistics and aggregation theory. [less ▲]

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See detailMeasuring the Interactions among Variables of Functions over the Unit hypercube
Marichal, Jean-Luc; Mathonet, Pierre ULg

in Modeling Decisions for Artificial Intelligence 7th International Conference, MDAI 2010 (2010)

By considering a least squares approximation of a given square integrable function f:[0,1]^n to R by a multilinear polynomial of a specified degree, we define an index which measures the overall ... [more ▼]

By considering a least squares approximation of a given square integrable function f:[0,1]^n to R by a multilinear polynomial of a specified degree, we define an index which measures the overall interaction among variables of f. This definition extends the concept of Banzhaf interaction index introduced in cooperative game theory. Our approach is partly inspired from multilinear regression analysis, where interactions among the independent variables are taken into consideration. We show that this interaction index has appealing properties which naturally generalize the properties of the Banzhaf interaction index. In particular, we interpret this index as an expected value of the difference quotients of f or, under certain natural conditions on f, as an expected value of the derivatives of f. These interpretations show a strong analogy between the introduced interaction index and the overall importance index defined by Grabisch and Labreuche. Finally, we discuss a few applications of the interaction index. [less ▲]

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See detailMeasuring the interactions among variables of functions over the unit hypercube
Marichal, Jean-Luc; Mathonet, Pierre ULg

in Journal of Mathematical Analysis & Applications (2011), 380

By considering a least squares approximation of a given square integrable function f: [0,1]^n\to\R by a multilinear polynomial of a specified degree, we define an index which measures the overall ... [more ▼]

By considering a least squares approximation of a given square integrable function f: [0,1]^n\to\R by a multilinear polynomial of a specified degree, we define an index which measures the overall interaction among variables of f. This definition extends the concept of Banzhaf interaction index introduced in cooperative game theory. Our approach is partly inspired from multilinear regression analysis, where interactions among the independent variables are taken into consideration. We show that this interaction index has appealing properties which naturally generalize several properties of the Banzhaf interaction index. In particular, we interpret this index as an expected value of the difference quotients of f or, under certain natural conditions on f, as an expected value of the derivatives of f. Finally, we discuss a few applications of the interaction index in aggregation function theory. [less ▲]

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See detailMeasuring the phase of the scattering amplitude with vortex beams
Ivanov, Igor ULg

in Physical Review. D : Particles and Fields (2012), 85(7), 07600110

We show that colliding vortex beams instead of (approximate) plane waves can lead to a direct measurement of how the overall phase of the plane wave scattering amplitude changes with the scattering angle ... [more ▼]

We show that colliding vortex beams instead of (approximate) plane waves can lead to a direct measurement of how the overall phase of the plane wave scattering amplitude changes with the scattering angle. Since vortex beams are coherent superpositions of plane waves with different momenta, their scattering amplitude receives contributions from plane wave amplitudes with distinct kinematics. These contributions interfere, leading to the measurement of their phase difference. Although interference exists for any generic wave packet collision, we show that using vortex beams dramatically enhances sensitivity to the phase in comparison with nonvortex beams. Since the overall phase is inaccessible in a plane wave collision, this measurement would be of great importance for a number of topics in hadronic physics, for example, meson production in the resonance region, physics of nucleon resonances, and small angle elastic hadron scattering. [less ▲]

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See detailMeasuring the size of the broad line region in quasars with Microlensing-aided reverberation mapping
Sluse, Dominique ULg; Tewes, Malte

Conference (2015, June)

Owing to the advent of large area photometric surveys, the possibility to use broad band photometric data, instead of spectra, to measure the size of the broad line region of active galactic nuclei, has ... [more ▼]

Owing to the advent of large area photometric surveys, the possibility to use broad band photometric data, instead of spectra, to measure the size of the broad line region of active galactic nuclei, has raised a large interest. We will describe a new method using time-delay lensed quasars where one (or several) images are affected by microlensing due to stars in the lensing galaxy. Because microlensing decreases (or increases) the flux of the continuum compared to the broad line region, it changes the contrast between these two emission components. We show that this effect can be used to effectively disentangle the intrinsic variability of those two regions, offering the opportunity to perform reverberation mapping based on single band photometric data. Based on simulated light curves, we show that measurement of the size of the broad line region can be achieved using this method, provided one spectrum has been obtained independently during the monitoring. This method is complementary to photometric reverberation mapping and could also be extended to multi-band data. [less ▲]

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See detailMeasuring the Social Economy in the Framework of the National Accounts
Mertens de Wilmars, Sybille ULg

in Defourny, Jacques; Nyssens, Marthe; Develtere, Patrick (Eds.) et al The worldwide making of the social economy. Innovations and changes (2009)

Sybille Mertens examines a new major development in the recognition of the social economy (nonprofit organisations, cooperatives, mutuals, social enterprises. She describes the efforts of numerous ... [more ▼]

Sybille Mertens examines a new major development in the recognition of the social economy (nonprofit organisations, cooperatives, mutuals, social enterprises. She describes the efforts of numerous research teams around the world to improve the statistical knowledge and economic measurement of this sector, with aspecific focus on the development of satellite accounts. [less ▲]

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See detailMeasuring the Technical Efficiency of Airports in Latin America
Perelman, Sergio ULg; Serebrisky, Tomas

in Utilities Policy (2012), 22

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See detailMeasuring the thermophysical properties of materials at high temperature - Application to the additive manufacturing of alloy Ti-6Al-4V and of stainless steel 316L
Mertens, Anne ULg; Paydas, Hakan ULg; Reginster, Sylvie ULg et al

Conference (2013, November 07)

In view of optimising the microstructures of metallic materials and obtaining the desired properties, the accurate characterisation of the thermophysical behaviour of these materials has long been ... [more ▼]

In view of optimising the microstructures of metallic materials and obtaining the desired properties, the accurate characterisation of the thermophysical behaviour of these materials has long been considered of paramount importance e.g. by allowing for the in-situ study of phase transformations, by providing data for numerical simulations and, essentially, by contributing to a better understanding of the fundamental mechanisms at play during processing. In the present work, the thermophysical behaviour of Ti-alloy Ti-6Al-4V and of stainless steel 316L has been characterised in details, in order to reach a better understanding of the phenomena controlling the microstructures and mechanical properties of parts made by additive manufacturing techniques that appear nowadays very promising in view of the economic production of near-net-shape, complex and (almost) fully dense parts from metallic materials. In particular, the thermal conductivity of Ti-alloy Ti-6Al-4V and of stainless steel 316L at high temperature has been determined by combining dilatometry, Differential Scanning Calorimetry (DSC) and laser flash diffusivimetry based on Laplace’s equation : k(T)=α(T)ρ(T)Cp(T) where k(T) is the thermal conductivity (W/m*K) α(T) is the thermal diffusivity (mm2/s) ρ(T) is the specific mass (g/cm3) Cp(T) is the specific heat capacity (J/g*K). Since Ti-alloy Ti-6Al-4V and stainless steel 316L exhibit quite different physical behaviours, their careful comparison is shown to shed more light into the role of phenomena such as epitaxial growth, out-of-equilibrium phase transformations and/or internal stresses in the additive manufacturing of metallic materials. [less ▲]

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See detailMeasuring the Usability and Effectiveness of CAAD Tools and Applications
Attia, Shady ULg; Andersen, Marilyne

in Proceeding of the Education and research in Computer Aided Architectural Design in Europe Conference (2013, September)

Computer Aided Architectural Design (CAAD) decisions and judgments have been at the heart of architectural design practice. Despite the increasing popularity of computer aided design applications ... [more ▼]

Computer Aided Architectural Design (CAAD) decisions and judgments have been at the heart of architectural design practice. Despite the increasing popularity of computer aided design applications, measuring the decision making of designers empirically remains elusive. Past research claiming usefulness of the CAD has relied largely on anecdotal or case studies that are vulnerable to bias. The study reviews results of prior investigations. The relatively few laboratory experiments report hardly any empirical results regarding the measurement of CAD decision making. The study provides an overview of the literature of existing measurement methods that have been used in psychology and neuroscience to assess individual variations in design making, and highlight these different measurement methods’ strengths and weaknesses. We conclude with a comparative evaluation of the different measures and provide suggestions regarding their constructive use in building realistic theories of designer’s decision making measurement. [less ▲]

Detailed reference viewed: 73 (1 ULg)