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See detailImproving spatial information extraction for local and regional authorities using Very-High-Resolution data - geometric aspects.
Devriendt, Dennis; Goossens, Rudi; De Wulf, Alain et al

in International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences (2003), 34(XXX),

The purpose of the presented research project is to investigate how present-day EO-technology can support local and regional decision-making, particularly in Belgium, and to develop prototype versions of ... [more ▼]

The purpose of the presented research project is to investigate how present-day EO-technology can support local and regional decision-making, particularly in Belgium, and to develop prototype versions of value-added products that fulfil some of the actual information needs, as expressed by Belgian authorities at the local and at the regional level. To accomplish this goal the proposal addresses both technical and user-oriented issues, and builds on the experience of five research teams, each with its own background and particular know-how. The most important objectives of the project are: - to define optimal methods for improved spatial information extraction from high- and very-high resolution data, based on innovative processing techniques; - to identify useful EO-applications at the level of local and regional decision making that are made possible by applying the information extraction methods that will be developed; in this case especially 3D information - to define and develop value-added core data products that will support these applications, and that can be consulted with easy-to-use, widely available IT-tools (CD-ROM, Internet, …). One of the technical research modules is focussing on the geometrical aspects of VHR data processing. In terms of spatial resolution, VHR data have the required level of detail to resolve individual objects in the landscape, in a similar way as airborne data. As such, they have the potential of becoming a useful data source for the extraction of detailed, object-related information, and for the production of large-scale cartographic reference data. The geometry of VHR sensor data, however, completely differs from the geometry of aerial photographs (Bethel et al., 2001). Research is going on to evaluate the geometric qualities of present and future VHR standard data products, from the moment they become available, and to examine what level of geometric accuracy is attained with these data, depending on image parameters, processing strategies, and terrain characteristics (Zhou and Li, 2000). The main objectives of the research module on geometric aspects of VHR data processing are: a) to define an optimal procedure for the derivation of envelope DSMs (Digital Surface Models) and ortho-photoplans from VHR data; b) to develop a theoretical model to study the effect of the oblique viewing angle of VHR data on image displacements caused by building height and relief; c) to evaluate the geometric accuracy of satellite-derived envelope DSMs and ortho-corrected image data in comparison with similar products obtained by means of large-scale aerial photography. The module about geometrical aspects is divided into six specific tasks. a) GPS database creation b) Creation of reference envelope DSMs based on aerial photography c) Ortho-rectification of VHR images and aerial photography based on reference DSMs d) Evaluation of the quality of VHR geo-referenced data e) Modelling of displacements caused by terrain morphology and sensor viewing angle f) Development of envelope DEMs from VHR stereoscopic imagery The project is now in the stage where the quality of the georeferenced and orthorectified data is evaluated. [less ▲]

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See detailImproving strategies for detecting genetic patterns of disease susceptibility in association studies
Calle, M. L.; Urrea, V.; Malats, N. et al

in Statistics in Medicine (2008), 27(30), 6532-6546

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See detailImproving TCP in wireless networks with an adaptive machine-learnt classifier of packet loss causes
El Khayat, Ibtissam; Geurts, Pierre ULg; Leduc, Guy ULg

in Lecture Notes in Computer Science (2005, May), 3462

TCP understands all packet losses as buffer overflows and reacts to such congestions by reducing its rate. In hybrid wired/wireless networks where a non negligible number of packet losses are due to link ... [more ▼]

TCP understands all packet losses as buffer overflows and reacts to such congestions by reducing its rate. In hybrid wired/wireless networks where a non negligible number of packet losses are due to link errors, TCP is unable to sustain a reasonable rate. In this paper, we propose to extend TCP Newreno with a packet loss classifier built by a supervised learning algorithm called 'decision tree boosting'. The learning set of the classifier is a database of 25,000 packet loss events in a thousand of random topologies. Since a limited percentage of wrong classifications of congestions as link errors is allowed to preserve TCP-Friendliness, our protocol computes this constraint dynamically and tunes a parameter of the classifier accordingly to maximise the TCP rate. Our classifier outperforms the Veno and Westwood classifiers by achieving a higher rate in wireless networks while remaining TCP-Friendly. [less ▲]

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See detailImproving Teaching: A Need for Combined Strategies
Poumay, Marianne ULg

Scientific conference (2009, October 30)

The presentation will illustrate the efforts of the University of Liège in that new international trend: valorizing good teaching through : • portfolios, • training the teachers (certificates and degree ... [more ▼]

The presentation will illustrate the efforts of the University of Liège in that new international trend: valorizing good teaching through : • portfolios, • training the teachers (certificates and degree granting), • helping faculty implement pedagogical innovations, • deploying a web portal with multiple tools serving autonomous improvement, notably in eLearning. Could some of those tools be shared, in a Charter perspective? [less ▲]

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See detailImproving the Accuracy of Monitoring Great Apes in the Wild: A Case Study from Southeast Cameroon
Tagg, Nikki; Willie, Jacob; Petre, Charles-Albert ULg

in Folia Primatologica : International Journal of Primatology = Internationale Zeitschrift für Primatologie = Journal international de Primatologie (2013), 84

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See detailImproving the action of insulin.
Lefebvre, Pierre ULg; Scheen, André ULg

in Clinical & Investigative Medicine = Médecine Clinique et Experimentale (1995), 18(4), 340-7

Improving the action of insulin is a relatively new concept in diabetes management. Insulin sensitivity can be improved by reduction of excessive body weight, regular physical activity and, possibly, by ... [more ▼]

Improving the action of insulin is a relatively new concept in diabetes management. Insulin sensitivity can be improved by reduction of excessive body weight, regular physical activity and, possibly, by correcting a subclinical magnesium deficiency. Pharmacological means of improving insulin action include metformin, antiobesity serotoninergic agents and, possibly, benfluorex. New compounds aiming at improving the action of insulin are in development and include thiazolidinedione derivatives (known as "insulin sensitizers"), inhibitors of adipose tissue lipolysis (e.g. acipimox), and inhibitors of free fatty acid oxidation (e.g. etomoxir). Avoidance of drugs that reduce insulin sensitivity, such as beta blockers and thiazide diuretics, is recommended. Finally, cigarette smoking is associated with resistance to insulin but it remains to be demonstrated that cessation of cigarette smoking does in fact increase sensitivity to insulin. [less ▲]

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See detailImproving the alkalophilic performances of the Xyl1 xylanase from Streptomyces sp S38: Structural comparison and mutational analysis
De Lemos Esteves, Frédéric ULg; Gouders, T.; Lamotte-Brasseur, J. et al

in Protein Science : A Publication of the Protein Society (2005), 14(2), 292-302

Endo-beta-1,4-xylanases of the family 11 glycosyl-hydrolases are catalytically active over a wide range of pH. Xyl1 from Streptomyces sp. S38 belongs to this family, and its optimum pH for enzymatic ... [more ▼]

Endo-beta-1,4-xylanases of the family 11 glycosyl-hydrolases are catalytically active over a wide range of pH. Xyl1 from Streptomyces sp. S38 belongs to this family, and its optimum pH for enzymatic activity is 6. Xyn11 from Bacillus agaradhaerens and XylJ from Bacillus sp. 41M-1 share 85% sequence identity and have been described as highly alkalophilic enzymes. In an attempt to better understand the alkalophilic adaptation of xylanases, the three-dimensional structures of Xyn11 and Xyl1 were compared. This comparison highlighted an increased number of salt-bridges and the presence of more charged residues in the catalytic cleft as well as an eight-residue-longer loop in the alkalophilic xylanase Xyn11. Some of these charges were introduced in the structure of Xyl1 by site-directed mutagenesis with substitutions Y16D, S18E, G50R, N92D, A135Q, E139K, and Y186E. Furthermore, the eight additional loop residues of Xyn11 were introduced in the homologous loop of Xyl1. In addition, the coding sequence of the XylJ catalytic domain was synthesized by recursive PCR, expressed in a Streptomyces host, purified, and characterized together with the Xyl1 mutants. The Y186E substitution inactivated Xyl1, but the activity was restored when this mutation was combined with the G50R or S18E substitutions. Interestingly, the E139K mutation raised the optimum pH of Xyl1 from 6 to 7.5 but had no effect when combined with the N92D substitution. Modeling studies identified the possible formation of an interaction between the introduced lysine and the substrate, which could be eliminated by the formation of a putative salt-bridge in the N92D/E139K mutant. [less ▲]

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See detailImproving the bias/variance tradeoff of decision trees - towards soft tree induction
Geurts, Pierre ULg; Olaru, Cristina; Wehenkel, Louis ULg

in Engineering intelligent systems (2001), 9

One of the main difficulties with standard top down induction of decision trees comes from the high variance of these methods. High variance means that, for a given problem and sample size, the resulting ... [more ▼]

One of the main difficulties with standard top down induction of decision trees comes from the high variance of these methods. High variance means that, for a given problem and sample size, the resulting tree is strongly dependent on the random nature of the particular sample used for training. Consequently, these algorithms tend to be suboptimal in terms of accuracy and interpretability. This paper analyses this problem in depth and proposes a new method, relying on threshold softening, able to significantly improve the bias/variance tradeoff of decision trees. The algorithm is validated on a number of benchmark problems and its relationship with fuzzy decision tree induction is discussed. This sheds some light on the success of fuzzy decision tree induction and improves our understanding of machine learning, in general. [less ▲]

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See detailImproving the catabolic functions in desiccation-tolerant soil bacteria in view of their use in bioaugmentation.
Weekers, F.; Jacques, Ph.; Springael, D. et al

Poster (1998, May 08)

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See detailImproving the catabolic functions in dessication-tolerant soil bacteria in view of their use in bioaugmentation
Weekers, F.; Jacques, Ph.; Springael, D. et al

Poster (1998, May)

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See detailImproving The Catabolic Functions Of Desiccation-Tolerant Soil Bacteria
Weekers, F.; Jacques, P.; Springael, D. et al

in Applied Biochemistry and Biotechnology (1999), 77-9

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See detailImproving the Energy Efficiency of the Building Stock: A Bottom-up Model and its Application in an Online Interactive Portal
Cuvellier, Simon; Marique, Anne-Françoise ULg; Reiter, Sigrid ULg

in Proceedings of PLEA 2014 (2014)

There is an urgent need to reduce energy uses in new and retrofitted buildings. In Europe, energy consumption in the building sector still represents more than 40% of the final energy use. Emerging ... [more ▼]

There is an urgent need to reduce energy uses in new and retrofitted buildings. In Europe, energy consumption in the building sector still represents more than 40% of the final energy use. Emerging countries are also concerned by such issues at even wider levels because of the huge demographic growth they are witnessing. Numerous research studies have highlighted the need to produce more efficient buildings, but also to retrofit the existing building stock. However, research methods and tools that allow a precise quantification of energy uses in buildings and energy savings related to various actions (insulating the roofs, changing the glazing, behavioral changes, etc.) are mainly dedicated to trained professional users, thus neglecting the huge potential energy savings that is linked to individual actions undertaken by citizens in their dwellings. In this context, the main aim of our research is to raise awareness of energy efficiency in residential buildings and encourage positive changes to the energy efficiency of the building stock, starting at the individual scale. This paper first presents the methodology that allows a precise energy assessment (heating, cooling, ventilation, lighting, appliances and cooking) of buildings (at the house, neighborhood, city and region scales) on the basis of a “bottom-up” approach. This methodology uses a typological classification of buildings, thermal simulations and local surveys. In this paper, this methodology is applied to the Walloon (Belgium) building stock. Many parameters are defined and taken into account to capture the specificities of numerous types of buildings (e.g., the number of floors, common ownership, orientation, thermal performances, ventilation, etc.). Several occupation modes are modelled to capture the impact of occupants’ behavior on energy consumption. To take into account the impact of urban form, correction factors are defined and applied according to the type of neighborhoods in which the buildings are located. All things considered, 250,000 individual results are obtained and stored in a huge database. Linear extrapolations and correction factors are used to extrapolate and apply these results to any type of residential building in Wallonia. This methodology is then used to develop an online portal that aims to strengthen citizens’ awareness of the necessity for ecological changes in the building sector and encourage individual actions to improve the energy efficiency of buildings. This tool allows for a transfer of the main results of a two-year scientific research effort to citizens in a very simple and intuitive way. Although the results presented in this paper are focused on Wallonia (Belgium), the research is easily reproducible to other territories by adapting local parameters. [less ▲]

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See detailImproving the grinding performance in ball mills with a conductive and inductive sensor
Köttgen, Axel ULg; de Haas, Bernard; Keshav, Pratish et al

Poster (2010)

A series of tests were conducted in a South African concentrator on the secondary grinding mill. The results were analysed and provided showed the importance of selecting an optimum density and filling ... [more ▼]

A series of tests were conducted in a South African concentrator on the secondary grinding mill. The results were analysed and provided showed the importance of selecting an optimum density and filling degree of the mill. Moreover, a Sensomag (r) is installed on this mill and the surveys showed that an increase of the density was improving the mixing of balls in the pulp and increasing the grinding performance. [less ▲]

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See detailImproving the performance of low-gain designs for bounded control of linear systems
Grognard, F.; Sepulchre, Rodolphe ULg; Bastin, G.

in Automatica (2002), 38(11), 1777-1782

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See detailImproving the power of out of control states detection in multivariate processes using variable sampling intervals policy
Seif, A.; Faraz, Alireza ULg; Torabian, M.

in Journal of Applied Mathematics (2009), 23

The familiar multivariate process monitoring and control procedure is the Hotelling’s T2 control chart, a direct analog of the univariate shewhart chart. But, its efficiency for detecting small to ... [more ▼]

The familiar multivariate process monitoring and control procedure is the Hotelling’s T2 control chart, a direct analog of the univariate shewhart chart. But, its efficiency for detecting small to moderate shifts in the process mean is poor. To improve the power of chart, this paper presents the variable sampling intervals (VSI) scheme. It is assumed that the length of time the process remains in control has exponential distribution. The chart is modeled using Markov chains and is optimized using genetic algorithm optimization method. The results show that the T2 chart with variable ratio sampling scheme is quicker than the classical one in detecting almost all shifts in the process mean [less ▲]

Detailed reference viewed: 21 (4 ULg)