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See detailImproving control of storage diseases on apple by combining biological and physical postharvest methods
Creemers, P.; Van Laer, S.; Vorstermans, B. et al

Poster (2006)

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See detailImproving education for disadvantaged children: some Belgian studies
Osterrieth, Paul A.; De Coster, W.; Burion, J. et al

Book published by Pergamon Press/Van Leer (1977)

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See detailImproving effect of metal and oxide nanoparticles encapsulated in porous silica on fermentative biohydrogen production by Clostridium butyricum.
Beckers, Laurent; Hiligsmann, Serge ULg; Lambert, Stéphanie ULg et al

in Bioresource Technology (2013), 133C

This paper investigated the enhancement effect of nanometre-sized metallic (Pd, Ag and Cu) or metallic oxide (Fe(x)O(y)) nanoparticles on fermentative hydrogen production from glucose by a Clostridium ... [more ▼]

This paper investigated the enhancement effect of nanometre-sized metallic (Pd, Ag and Cu) or metallic oxide (Fe(x)O(y)) nanoparticles on fermentative hydrogen production from glucose by a Clostridium butyricum strain. These nanoparticles (NP) of about 2-3nm were encapsulated in porous silica (SiO(2)) and were added at very low concentration (10(-6)molL(-1)) in batch hydrogen production test. The cultures containing iron oxide NP produced 38% more hydrogen with a higher maximum H(2) production rate (HPR) of 58% than those without NP or with silica particles only. The iron oxide NP were used in a 2.5L sequencing-batch reactor and showed no significant effect on the yields (established at 2.2mol(hydrogen)mol(glucose)(-1)) but an improvement of the HPR (+113%, reaching a maximum HPR of 86mL(hydrogen)L(-1)h(-1)). These results suggest an improvement of the electron transfers trough some combinations between enzymatic activity and inorganic materials. [less ▲]

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See detailImproving energy efficiency of existing suburban areas through district energy planning
Marique, Anne-Françoise ULg; Reiter, Sigrid ULg

in Proceedings of ISHVAC 2011 (2011, November)

Urban sprawl represents a significant contribution to the overall energy consumption of a territory for energy needs in buildings and for transport. It is a huge concern in Belgium where public ... [more ▼]

Urban sprawl represents a significant contribution to the overall energy consumption of a territory for energy needs in buildings and for transport. It is a huge concern in Belgium where public authorities face the following question: “what to do with existing low-density districts that require a lot of resources?” while households still continue to favour this kind of dwellings. In this context, the paper draws up a typological classification of reference Walloon suburban blocks. Then, energy savings relating to several types of renewal strategy are evaluated. These strategies deal with the measures to reduce heat demand in buildings, to increase the built density and to reduce energy consumption in the transport sector. Results from this analysis show that a strong potential exists to improve energy efficiency in existing suburban districts. Building insulation and travel distances are critically important factors. Solar gains on the roofs are huge even if the built density is increased. [less ▲]

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See detailImproving functional performance and muscle power 4-to-6 months after anterior cruciate ligament reconstruction
Souissi, Sabrine; Wong, Del P.; Dellal, Alexandre et al

in Journal of Sports Science & Medicine (2011), 10

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See detailImproving Generalization for 3D Object Categorization with Global Structure Histograms
Madry, Marianna; Ek, Carl Henrik; Detry, Renaud ULg et al

in IEEE/RSJ International Conference on Intelligent Robots and Systems (2012)

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See detailIMPROVING GENOMIC PREDICTION BY EUROGENOMICS COLLABORATION
Lund, M. S.; de Roos, A. P. W.; de Vries, A. G. et al

in Proceedings of the 9th World Congress on Genetics Applied to Livestock Production (2010)

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See detailImproving groundwater flow model conceptualisation and calibration with electrical resistivity tomography and self-potential methods
Robert, Tanguy ULg; Therrien, René; Lemieux, Jean-Michel et al

Conference (2011, September 19)

Developing a conceptual model for groundwater flow requires knowledge on the distribution of geological materials, which generally comes from geological observations on outcrops and boreholes, from the ... [more ▼]

Developing a conceptual model for groundwater flow requires knowledge on the distribution of geological materials, which generally comes from geological observations on outcrops and boreholes, from the interpretation of hydraulic tests or from geophysical surveys. The identification of spatial structures in the subsurface, such as preferential flow paths created by fractured zones, is also critical in developing a reliable conceptual model but it is difficult to achieve. Geophysical methods have been widely used to map the subsurface distribution of geological materials. Recent developments in geophysics, such as the increased use of joint inversion of geophysical and hydrogeological data, have further allowed to quantify the hydraulic conductivity of geological materials. The objective of our work is to demonstrate that the electrical resistivity tomography (ERT) and the self-potential (SP) methods can improve both the conceptual model developed for groundwater flow systems and the calibration of the corresponding groundwater flow model. The use of the two geophysical methods, combined with a groundwater flow model, is presented for a fractured limestone aquifer. The self-potential method relies on passive measurements of the ambient electrical potential at ground surface or in boreholes. One of the mechanisms responsible for the measured signal measured is the transport of dissolved ions with groundwater flow. When this electrokinetic effect is the dominant contribution, the resulting signal is called the streaming potential and it contains information about groundwater fluxes that can be useful to calibrate groundwater flow models. The solution to the SP forward problem was added to the HydroGeoSphere model, which simulates 3D groundwater flow and solute transport in porous media, including fractured geological formations. With this addition, the model can calculate the self-potential signal associated with groundwater flow, given the distribution of Darcy fluxes resulting from the forward flow solution and the electrical resistivity that is, for example, outputted by ERT data inversion. Darcy fluxes are transformed into sources of electrical current by using the streaming potential coupling coefficient. This parameter can be measured either in the laboratory or in-situ from the self-potential signal between two locations where the depth of the water table is known, such as observation wells. We used here both ERT and SP to develop a conceptual model for groundwater flow in a typical carboniferous limestone syncline in South Belgium. The rolling topography in the investigated area results from a succession of calcareous valleys (synclines) and sandstone crests (anticlines). The calcareous synclines form aquifers that are very complex since they are highly fractured and even karstified. A typical calcareous syncline has a width of about 800 m and, using ERT, we could subdivide the syncline into zones of different hydraulic conductivity, based on the degree of fracturation. The zones are oriented along the axis of the syncline and their width ranges between 10 and 40 m. The ERT profiles showed that there is a highly conductive zone, in terms of electrical conductivity, near the syncline fold axis. That zone is interpreted as being highly fractured. Other conductive zones are located symmetrically along both flanks of the calcareous syncline, with respect to the syncline fold axis. The main flow direction is along the axis of the syncline, towards a nearby river. The SP raw signals also showed that, locally, there is a second flow component perpendicular to the axis of the syncline, with groundwater flowing from the flanks of the syncline towards the axis. The conceptual groundwater flow model developed here includes the zones identified with ERT, which were then incorporated into the numerical model. The SP signals were inverted with PEST to calibrate the hydraulic conductivity value of the different zones. HydroGeoSphere was therefore used to simulate first groundwater flow and then the associated self-potential signals in an iterative process. At the start of an iteration, HydroGeoSphere solves the groundwater flow equation given one particular set of hydraulic conductivities and calculates the resulting Darcy fluxes. These fluxes are transformed into sources of electrical current assuming that the electrokinetic effect is the dominant contribution of the SP signals. HydroGeoSphere then calculates the distribution of self-potential given the sources of electrical current and the distribution of electrical resistivity. The hydraulic conductivity values of the zones are then modified and the iteration continues until the model reproduces the measured self-potential signal. [less ▲]

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See detailImproving Groundwater Flow Model Conceptualisation and Calibration with ERT and Self-potential Methods
Robert, Tanguy ULg; Therrien, René; Lemieux, Jean-Michel et al

in EarthDoc - Near Surface 2011 – 17th European Meeting of Environmental and Engineering Geophysics (2011, September 14)

The self-potential (SP) method relies on passive measurements of the ambient electrical potential at the ground surface or in boreholes. When the electrokinetic effect is the dominant contribution, the ... [more ▼]

The self-potential (SP) method relies on passive measurements of the ambient electrical potential at the ground surface or in boreholes. When the electrokinetic effect is the dominant contribution, the resulting signal is called the streaming potential and contains information about groundwater fluxes that can be useful for calibration of groundwater flow models. The streaming potential forward equation was implemented in the HydroGeoSphere model, which simulates 3D groundwater flow and solute transport in porous media, including fractured geological formations. HydroGeoSphere is able to calculate the streaming potential given a distribution of Darcy velocity and electrical resistivity. Since groundwater flow modelling relies on a conceptual model, prior information on the distribution of the geological units and hydraulic conductivity at the site is mandatory. However, this information is often scarce or missing. In this work, we use the electrical resistivity tomography (ERT) and the SP methods as an additional source of information for building the groundwater flow model. ERT is used to identify the location of fractured zones in a fractured and karstified calcareous aquifer of South Belgium. The SP signal is used with PEST in order to calibrate the groundwater flow model and better constrain the hydraulic conductivity of the fractured zones. [less ▲]

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See detailImproving halva quality with dietary fibres of sesame seed coats and date pulp, enriched with emulsifier
Elleuch, Mohamed; Bedigian, Dorothea; Maazoun, Bouthaina et al

in Food Chemistry (2014), 145

Supplementation of halva with waste products of manufacturing, for example defatted sesame seed coats (testae) and date fibre concentrate, can improve its nutritional and organoleptic qualities. These ... [more ▼]

Supplementation of halva with waste products of manufacturing, for example defatted sesame seed coats (testae) and date fibre concentrate, can improve its nutritional and organoleptic qualities. These constituents provide high fibre content and technological potential for retaining water and fat. Standard halva supplemented with date fibre concentrate, defatted sesame testae and emulsifier was evaluated for oil separation, texture and colour changes, sensory qualities and acceptability to a aste panel. Addition of both fibres with an emulsifier, improved emulsion stability and increased the hardness of halva significantly. The functional properties of sesame testae and date fibres promote nutrition and health, supplying polyphenol antioxidants and laxative benefits. [less ▲]

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See detailImproving in-row weed detection in multispectral stereoscopic images
Piron, Alexis ULg; Leemans, Vincent ULg; Lebeau, Frédéric ULg et al

in Computers & Electronics in Agriculture (2009), 69

Previous research has shown that plant height and spectral reflectance are relevant features to classify crop and weeds in organic carrots: classification based on height gave a classification accuracy ... [more ▼]

Previous research has shown that plant height and spectral reflectance are relevant features to classify crop and weeds in organic carrots: classification based on height gave a classification accuracy (CA) of up to 83% while classification based on a combination of three multispectral bands gave a CA of 72%. The first goal of this study was to examine the simultaneous use of both height and multispectral parameters. It was found that classification rate was only slightly improved when using a feature set comprising both height and multispectral data (2%). The second goal of this study was to improve the detection method based on plant height by setting an automatic threshold between crop and weeds heights, in their early growth stage. This threshold was based on crop row determination and peak detection in plant height probability density function, corresponding to the homogeneous crop population. Using this method, the CA was 82% while the CA obtained with optimal plant height limits is only slightly higher at 86%. [less ▲]

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See detailImproving Interferometric Null Depth Measurement with statistics : theory and first results with the Palomar Fiber Nuller
Hanot, Charles ULg

Scientific conference (2010, June)

A new "self-calibrated" statistical analysis method has been developed for reducing nulling interferometry data. The idea is to use the statistical distributions of the fluctuating null depths and beam ... [more ▼]

A new "self-calibrated" statistical analysis method has been developed for reducing nulling interferometry data. The idea is to use the statistical distributions of the fluctuating null depths and beam intensities to retrieve the astrophysical null depth (or equivalently the object's visibility) in the presence of fast instrumental fluctuations. The approach yields an accuracy much better (at least ten times) than is presently possible with standard data reduction methods, because the null depth accuracy is no longer limited by the magnitude of the phase and intensity errors but by uncertainties on their probability distributions. This approach was tested on the sky with the two-aperture fiber nulling instrument mounted on the Palomar Hale telescope. Using our new data analysis approach alone - and no observations of calibrators - , we find that astrophysical null depths lower than 0.001 can be reliably measured in the near infrared, with error bars as low as a few 10^-4. This statistical analysis is not specific to our instrument and may be applicable to other interferometers. Therefore I'll also present the application of this method to the measurement of Cepheids angular diameters at the VLTI with a sensitivities down to ~60µas. [less ▲]

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See detailImproving Interferometric null depth measurements using statistical distributions: theory and first results with the Palomar Fiber Nuller
Hanot, Charles ULg; Mennesson, Bertrand; Martin, Stefan et al

in Astrophysical Journal (2011), 729(2), 110

A new "self-calibrated" statistical analysis method has been developed for the reduction of nulling interferometry data. The idea is to use the statistical distributions of the fluctuating null depth and ... [more ▼]

A new "self-calibrated" statistical analysis method has been developed for the reduction of nulling interferometry data. The idea is to use the statistical distributions of the fluctuating null depth and beam intensities to retrieve the astrophysical null depth (or equivalently the object's visibility) in the presence of fast atmospheric fluctuations. The approach yields an accuracy much better (about an order of magnitude) than is presently possible with standard data reduction methods, because the astrophysical null depth accuracy is no longer limited by the magnitude of the instrumental phase and intensity errors but by uncertainties on their probability distributions. This approach was tested on the sky with the two-aperture fiber nulling instrument mounted on the Palomar Hale telescope. Using our new data analysis approach alone—and no observations of calibrators—we find that error bars on the astrophysical null depth as low as a few 10–4 can be obtained in the near-infrared, which means that null depths lower than 10–3 can be reliably measured. This statistical analysis is not specific to our instrument and may be applicable to other interferometers. [less ▲]

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See detailImproving micropropagation of Dioscorea cayenensis – D. rotundata complex by the use of nodal cuttings and microtubers
Ondo Ovono, Paul; Kevers, Claire ULg; Dommes, Jacques ULg

in Acta Agriculturae Scandinavica : Section B - Soil & Plant Science (2013), 63(7), 653-656

Yams (Dioscorea spp) are tuber crops used as staple food in Africa because of their nutritional value. In contrast to the inefficiency of traditional method of planting, micropropagation by nodal cuttings ... [more ▼]

Yams (Dioscorea spp) are tuber crops used as staple food in Africa because of their nutritional value. In contrast to the inefficiency of traditional method of planting, micropropagation by nodal cuttings allows to increase the multiplication and the rapid production of pathogen free plant material. The first aim ofIn this work was to show tha,t micropropagation of yam from both nodal cuttings and microtubers was first possible tested both from nodal cuttings and from microtubersand compared. It appears that microtubers rapidly develop shoots, more rapidly than nodal cuttings. Respectively 16 and 28 weeks are needed to obtain 10 cm high shoots. In a second time, the two techniques of multiplication were used in parallel to improve the multiplication rate. So, one nodal cutting after 28 weeks of culture can be subcultured as nodal cuttings (for 28 other weeks) and as microtuber parts (for 16 weeks). At the end of each subculture of nodes or microtubers, nodal cuttings and microtubers were cut and subcultured. This technique allowed obtaining more rapidly a lot of microtubers. The use of nodal cuttings allowed obtaining about 3 104 cuttings in 2 years. The additional use of the formed microtubers and the division of the microtubers at the subculture in three parts increased this multiplication rate by 15. The importance of this work was to consider microtubers not only as final planting product, but also to include them in the in vitro multiplication protocol to drastically increase the production of cuttings and finally of microtubers. [less ▲]

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See detailImproving model-based cardiac diagnosis with an ECG
Hann, C. E.; Chase, J. G.; Desaive, Thomas ULg et al

in Proceedings (CD) of the 4th European Congress for Medical and Biomedical Engineering (eMBEC 2008), Antwerp, Belgium, Nov 23-27, 2008 (2008)

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See detailImproving Null Depth Measurement with statistics : theory and first results with the Palomar Fiber Nuller
Hanot, Charles ULg

Scientific conference (2010, February)

A unique statistical data analysis method has been developed for reducing nulling interferometry data. The idea is to make use of the statistical distributions of the fluctuating null depths and beam ... [more ▼]

A unique statistical data analysis method has been developed for reducing nulling interferometry data. The idea is to make use of the statistical distributions of the fluctuating null depths and beam intensities to retrieve the astrophysical null depth in the presence of fluctuations. The approach yields an accuracy much better than is possible with standard data reduction methods, because the accuracy of the null depth is not limited by the sizes of the phase and intensity errors but by the uncertainties on these errors. The result is an improvement in the instrumental null depth measurement limit of roughly an order of magnitude. We show in this paper that broadband null depths of 10-4 can be measured in the lab with our infrared Fiber Nuller without achromatic phase shifters. On sky results are also dramatically improved, with measured contrasts up to 5 x 10-4 with our instrument mounted on the Hale telescope at the Palomar Observatory. This statistical analysis is not specific to our instrument and may be applicable to other interferometers. [less ▲]

Detailed reference viewed: 9 (4 ULg)