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See detailStrategic Design, Optimization, and Modelling Issues of Net-Zero Energy Solar Buildings
Athienitis, Andreas; Attia, Shady ULiege

in Proceedings of Eurosun 2010 (2010, September)

The design of net-zero energy solar buildings (NZESBs) presents a challenge because there is no established design strategy to systematically reach this goal and many of the available building energy ... [more ▼]

The design of net-zero energy solar buildings (NZESBs) presents a challenge because there is no established design strategy to systematically reach this goal and many of the available building energy tools have limited applicability for such advanced buildings. This paper reviews current design practice and tools for designing NZESBs through a literature review and a survey. It also discusses modelling issues and presents the procedure used in several redesign and optimization case studies of existing NZESBs that Subtask B (STB) of the IEA SHC Task 40/ECBCS Annex 52 project “Towards Net Zero Energy Solar Buildings” is performing. The case studies will identify gaps in existing tools and help develop strategies for the use of design tools in establishing near optimal NZESB designs. [less ▲]

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See detailRisk stratification in asymptomatic moderate to severe aortic stenosis: the importance of the valvular, arterial and ventricular interplay.
Lancellotti, Patrizio ULiege; Donal, Erwan; Magne, Julien ULiege et al

in Heart (2010), 96(17), 1364-71

OBJECTIVE: We sought to evaluate prognostic markers of clinical outcome in asymptomatic patients with moderate to severe aortic stenosis (AS). DESIGN: Prospective follow-up of asymptomatic patients with ... [more ▼]

OBJECTIVE: We sought to evaluate prognostic markers of clinical outcome in asymptomatic patients with moderate to severe aortic stenosis (AS). DESIGN: Prospective follow-up of asymptomatic patients with moderate to severe AS. The patients underwent clinical and Doppler echocardiographic evaluation. SETTING: Department of Cardiology. PATIENTS: 163 patients with moderate to severe AS (aortic valve area < or =0.6 cm(2)/m(2)). MAIN OUTCOME MEASURES: Risk stratification. Predefined endpoints for assessing the outcome were the occurrence during follow-up of symptoms, aortic valve replacement or death. RESULTS: During follow-up (mean, 20 (19) months), 11 patients developed symptoms but were not operated on, 57 required aortic valve replacement and six patients died. In multivariable Cox regression analysis, four parameters that were associated with the outcome were identified: peak aortic jet velocity, left ventricular systolic (LV) longitudinal deformation, valvulo-arterial impedance and indexed left atrial area. Using receiver-operator characteristic curve analysis, a peak aortic jet velocity > or =4.4 m/s, a LV longitudinal myocardial deformation < or =15.9%, a valvular-arterial impedance > or =4.9 mm Hg/ml per m(2) and an indexed left atrial area > or =12.2 cm(2)/m(2) were identified as the best cut-off values to be associated with events. CONCLUSIONS: In asymptomatic patients with moderate to severe AS, measurements that integrate the ventricular, vascular and valvular components of the disease improve risk stratification. [less ▲]

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See detailGroundwater model parameter identification using a combination of cone-penetration tests and borehole data
Rogiers, Bart; Schiltz, Marco; Beerten, Koen et al

in International Groundwater Symposium 2010, IAHR (2010, September)

In the framework of the disposal of short-lived low- and intermediate-level radioactive waste in a near-surface disposal facility in Dessel, Belgium, additional extensive site characterisation has been ... [more ▼]

In the framework of the disposal of short-lived low- and intermediate-level radioactive waste in a near-surface disposal facility in Dessel, Belgium, additional extensive site characterisation has been performed in 2008. The gathered data now include 388 hydraulic conductivity measurements on samples from 8 cored boreholes. Detailed characterisation of these cored boreholes, together with geophysical logging, enabled to identify various hydrostratigraphical units at 8 discrete locations in the research area. Various analyses were performed on the cores, yielding information on grain size, mineralogy, density and total porosity. Geophysical logging parameters were derived from gamma-ray and resistivity measurements. Subsequently, an extensive geotechnical logging campaign was performed in order to establish a 3D-model of the hydrostratigraphical units, based on a dense network of investigation points. About 180 cone penetration tests (CPTs) were executed and lithology was deduced in detail based on existing soil classi cation charts. As such, a description of the regional subsurface up to depths of nearly 50 m was established, and this information was integrated with the borehole data. Most importantly, the lateral extent, depth and thickness of a hydrogeologically important aquitard was identi fied. Based on the 2008 site characterisation results and their interpretation, an update of a ground- water fl ow model used in safety assessments was made. The CPT-based stratigraphic model and the hydraulic conductivity data determined at different scales were combined into a new 3D hydrostratigraphical model. The small-scale measurements (on 100 cm³ core samples) are compared with hydraulic conductivity values obtained from pumping tests and the large-scale parameters derived by inverse modelling. The performance of the original and the updated flow model are compared. The presented approach was succesfull in substantially decreasing the conceptual model and parameter uncertainty and resulted in an improved calibration of the groundwater flow model. [less ▲]

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See detailEcology of the Belizean black howler monkey (Alouatta pigra): a comparison between two populations living in a riparian forest and on coastal limestone hills
Trolliet, Franck ULiege

Master's dissertation (2010)

This study reports on the ecology of the Belizean black howler monkey (Alouatta pigra) in two different habitats. Monkey River is a riparian secondary forest whereas Runaway Creek Nature Reserve (RCNR) is ... [more ▼]

This study reports on the ecology of the Belizean black howler monkey (Alouatta pigra) in two different habitats. Monkey River is a riparian secondary forest whereas Runaway Creek Nature Reserve (RCNR) is a primary and mature forest situated in a limestone karst hills landscape. This type of ecosystem, neither the population inhabiting this reserve, has been studied before. We contrasted food availability, diet, group size and composition, population density, home range size and activity patterns between those two populations. We predicted the disturbed riparian forest to have higher food availability but a less diverse diet with a higher consumption of fruits. Thus, we predicted howlers to have higher population density, larger groups with more males and more infants, smaller home ranges with more overlapping. Also, we predicted activity budget to be biased toward a less active lifestyle with less travel but more inactivity, and more social interactions. Our results confirm some of those predictions as food availability is higher in Monkey River with food species accounting for 80% of the diet and all food species of howlers diet having a higher total relative basal area. This is likely to be associated with the higher population density (44.82ind/km² in Monkey River against 26in/km² in RCNR) and smaller average home range size (3.27 ha against 11.87 ha) with a higher proportion of overlapping (11.87% against 0%). Predictions on group size and composition are not confirmed as the difference in mean group size is not statistically significant and as many males per group are found in both habitats (one) but sex ratios (M:F) indicate the presence of more females in Monkey River (1:1.6 against 1:1.3). Also, more infants per group are found in RCNR (0.6 in Monkey River against 1 in RCNR). Those results are likely to be associated with different stage of population growth between the two habitats and more precisely of the hurricane Iris that have lowered the population in Monkey River and allowed more dispersal opportunities and, resulting effects of social factors such as infanticide. Nevertheless, our results indicate howler population to increase again in this disturbed forest. Howlers in RCNR have a more diverse diet (18 food sources in Monkey River against 23 in RCNR) which is likely to be due to higher diversity of plants present in the limestone karst hills. Diets in both habitats differ as only 19.5% of species are similar and species composition in both habitats are pretty different too, which confirms howlers having a flexible diet and being able to adapt their diet to the species found in the habitat. Both populations feed preferentially on leaves but howlers in the secondary forest spent more time feeding on fruits (20.46%) and less on flowers (6.46%) than in the primary forest (11% and 11.75% respectively), although those differences are not significant. Howlers in Monkey River are more active and travel significantly more (9.45% against 5.45%) which is likely to be due to the higher amount of fruits in the diet. Less time is spent in social interactions in Monkey River, which is likely to be due to the smaller number of infants per group. Finally, monkeys in the secondary forest spent significantly more time vocalizing than in the primary forest, which is likely to be due to the higher population density and level of overlap between neighboring groups. No overlap has been recorded in the limestone karst hills and percentage of vocalization is quite low. [less ▲]

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See detailMan-Made Noise in Our Living Environments
Leferink, Frank; Silva, Ferran; Catrysse, Johan et al

in Radio Science Bulletin (2010), 334

The ITU’s (International Telecommunication Union’s) man-made noise levels are based on measurements performed in the 1970s. Some measurements have been carried out since then, showing that noise caused by ... [more ▼]

The ITU’s (International Telecommunication Union’s) man-made noise levels are based on measurements performed in the 1970s. Some measurements have been carried out since then, showing that noise caused by automotive ignition systems has been reduced, but manmade noise in business areas and city centers increased, especially due to the widespread use of electronic systems. The interference scenario also changed, from analog communication systems in relatively free-space conditions, to digital systems in living areas, often semi-enclosed such as offi ces, industrial production plants, and even inside cars and trains. Several measurements have therefore been carried out to estimate the level of man-made noise in these semi-enclosed environments. [less ▲]

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See detailPreventing introductions of invasive alien plants in Belgium: a LIFE "Information & Communication" project dedicated to the ornamental sector
Halford, Mathieu ULiege; Heemers, Leen; Mathys, Catherine et al

Poster (2010, September)

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See detailWide band SAR sub-band splitting and inter-band coherence measurements
De Rauw, Dominique ULiege; Orban, Anne ULiege; Barbier, Christian ULiege

in Remote Sensing Letters (2010), 1(3), 133-140

Range resolution of SAR images is determined by transmitted radar signal bandwidth. Most recent SAR sensors use wide band signals in order to achieve metric range resolution, whereas metric azimuth ... [more ▼]

Range resolution of SAR images is determined by transmitted radar signal bandwidth. Most recent SAR sensors use wide band signals in order to achieve metric range resolution, whereas metric azimuth resolution can be achieved in spotlight mode. As an example, ENVISAT ASAR sensor uses a 15-MHz bandwidth chirp whereas TerraSAR-X spotlight mode uses signals having a 150-MHz bandwidth leading to a potentially 10 times higher resolution. One can also take advantage of wide band to split the full band into sub-bands and generate several lower resolution images from a single acquisition, each being centred on slightly different frequencies. These sub-images can then be used in a classical interferometric process to measure inter-band coherence of a given scene. This inter-band coherence reveals scatterers keeping a stable-phase behaviour along with frequency shift. A simple coherence model derived from Zebker model for randomly distributed surface scatterers is proposed. Examples are presented, showing that scatterers can have a behaviour that deviates from the model, leading to a new information channel. [less ▲]

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See detailDevelopment of an immobilisation device for treatment of patients after breast conserving surgery for mammary carcinoma.
COUCKE, Philippe ULiege; WONNER, Michel ULiege; JANVARY, Zsolt Levente ULiege et al

Poster (2010, September)

To develop an immobilisation device for prone positioning for breast irradiation. The basic requirements for the device are: rapid and accurate patient (re)positioning, compatibility with modern imaging ... [more ▼]

To develop an immobilisation device for prone positioning for breast irradiation. The basic requirements for the device are: rapid and accurate patient (re)positioning, compatibility with modern imaging devices and easy to handle by the treating technologists. [less ▲]

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See detailExperience feed back committee (EFBC) in radiotherapy
DELGAUDINE, Marie ULiege; JANSEN, Nicolas ULiege; COUCKE, Philippe ULiege

Poster (2010, September)

Radiotherapy is a powerful continuously evolving effective treatment tool. Our aim is to offer the best treatments and assure security for patients and personnel. A proactive quality approach copied from ... [more ▼]

Radiotherapy is a powerful continuously evolving effective treatment tool. Our aim is to offer the best treatments and assure security for patients and personnel. A proactive quality approach copied from the one implemented in the air transport industry has been established in our department. An Experience feed back committee (EFBC) has been set up to identify, record and analyze systematically all reported precursor events. Our final objective is to test and strengthen the security of the organization and the quality of care for patients. [less ▲]

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See detailEVALUATION OF THE AUTOMATIC IMAGE REGISTRATION FEATURES OF A KV CONE-BEAM CT IMAGING SYSTEM
JANVARY, Zsolt Levente ULiege; JANSEN, Nicolas ULiege; MATHOT, Michel ULiege et al

Poster (2010, September)

As a part of the clinical implementation of a kV cone-beam CT (CBCT) volumetric imaging system for new Elekta Synergy linear accelerators, the automatic image registration (IR) system of the XVI Software ... [more ▼]

As a part of the clinical implementation of a kV cone-beam CT (CBCT) volumetric imaging system for new Elekta Synergy linear accelerators, the automatic image registration (IR) system of the XVI Software was studied. We examined the effect of the variability of matching parameters of the software on the results of the patient position errors. [less ▲]

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See detailSub-quadratic Markov tree mixture learning based on randomizations of the Chow-Liu algorithm
Ammar, Sourour; Leray, Philippe; Schnitzler, François ULiege et al

in Myllymäki, Petri; Roos, Antoine; Jaakkola, Tommi (Eds.) Proceedings of the Fifth European Workshop on Probabilistic Graphical Models (PGM-2010) (2010, September)

The present work analyzes different randomized methods to learn Markov tree mixtures for density estimation in very high-dimensional discrete spaces (very large number n of discrete variables) when the ... [more ▼]

The present work analyzes different randomized methods to learn Markov tree mixtures for density estimation in very high-dimensional discrete spaces (very large number n of discrete variables) when the sample size (N ) is very small compared to n. Several sub- quadratic relaxations of the Chow-Liu algorithm are proposed, weakening its search proce- dure. We first study na¨ıve randomizations and then gradually increase the deterministic behavior of the algorithms by trying to focus on the most interesting edges, either by retaining the best edges between models, or by inferring promising relationships between variables. We compare these methods to totally random tree generation and randomiza- tion based on bootstrap-resampling (bagging), of respectively linear and quadratic com- plexity. Our results show that randomization becomes increasingly more interesting for smaller N/n ratios, and that methods based on simultaneously discovering and exploiting the problem structure are promising in this context. [less ▲]

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See detailExploration des relations entre les capacités sémantiques et le manque du mot chez la personne âgée saine
Verhaegen, Clémence ULiege; Poncelet, Martine ULiege; Kaivers, Vinciane

Poster (2010, September)

Le manque du mot (ou anomie) est une plainte langagière fréquente chez le sujet âgé. Les facteurs cognitifs qui y contribuent et l’âge auquel il apparaît sont cependant controversés (Mortensen et al ... [more ▼]

Le manque du mot (ou anomie) est une plainte langagière fréquente chez le sujet âgé. Les facteurs cognitifs qui y contribuent et l’âge auquel il apparaît sont cependant controversés (Mortensen et al., 2006). Selon Barresi et al. (2000), l’anomie serait liée à une dégradation des représentations sémantiques chez les personnes de plus de 70 ans, les erreurs de dénomination d’images commises par celles-ci étant consistantes contrairement à celles observées chez les personnes de 50-60 ans. Le but de cette étude est de déterminer l’âge d’apparition de l’anomie et d’examiner plus directement les liens entre celle-ci et les capacités sémantiques chez la personne plus âgée. Nous avons évalué les capacités de dénomination d’images d’objets (issues de Bonin et al., 2003) ainsi que de jugement de synonymie et d’association sémantique d’images de trois groupes (N=19-18-19) de personnes saines (score>137 à l’échelle de Mattis), âgés respectivement de 25-35 ans, 50-60 ans et plus de 70 ans. Des ANOVA sur les réponses correctes et les temps de réponse en dénomination d’images révèlent un effet de groupe (respectivement, F(2,53)=21.76, p<.001 et F(2,53)=53.29, p<.001). Les personnes de plus de 70 ans sont plus lentes et commettent plus d’erreurs que les personnes de 50-60 ans et de 25-35 ans qui ne diffèrent pas entre elles. Un effet de groupe apparaît également dans les tâches de jugement de synonymie (F(2,53)=24.71, p<.001) et d’association sémantique (F(2,53)=15.40, p<.01). Les personnes de plus de 70 ans présentent des performances à ces tâches inférieures à celles des deux autres groupes d’âge, égaux entre eux. Cette étude montre que les capacités de dénomination sont altérées chez les personnes de plus de 70 ans mais pas de 50-60 ans et appuie la conception selon laquelle cette altération pourrait être liée à une dégradation des représentations sémantiques chez les personnes plus âgées. [less ▲]

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See detailWheat Yield Estimates at NUTS-3 level using MODIS data: an approach based on the decreasing curves of green area index temporal profiles
Kouadio, Amani Louis ULiege; Duveiller, Gregory; Djaby, Bakary ULiege et al

in Cawkwell, Fiona (Ed.) Proceedings of RSPSoc2010 Annual Conference. 1st-3rd September 2010, Cork, Ireland (Nottingham: RSPSoc) (2010, September)

Wheat is the most widely-grown food crop in the world and the most important cereal crop traded on international markets. An early prediction of its yield prior to harvest at regional, national and ... [more ▼]

Wheat is the most widely-grown food crop in the world and the most important cereal crop traded on international markets. An early prediction of its yield prior to harvest at regional, national and international scales can play a crucial role in global markets, policy and decision making. Many models for yield forecasting are available with varying levels of complexity and empiricism. The use of remote sensing technology for monitoring crop condition and predicting crop yields at regional scales have been studied extensively during these last decades. Earth observation data, owing to their synoptic, timely and repetitive coverage, have been recognized as a valuable tool for yield and production forecasting. At field level, studies on crop breeding showed that a close correlation exists between green leaf area during maturation and grain yield in wheat. Thus, the onset and rate of senescence appeared as important factors for determining grain yield of this crop. The aim of this research is to explore a simplified approach for wheat yield forecasting at the European NUTS-3 administrative level, based on metrics derived from the senescence phase of green area index (GAI) estimated from remote sensing data. This study takes advantage of considerable recent improvements in sensor technology and data availability through the opportunity of applying medium/coarse spatial resolution data for deriving crop specific GAI time series by selecting pixels whose ground-projected instantaneous field of view is constituted by a high cover fraction of winter wheat. This approach is tested on 2 crop growing season over a 300 by 300 km study site comprising Belgium and northern France within the framework of the GLOBAM (GLObal Agricultural Monitoring systems by integration of earth observation and modelling techniques) project. The validation of such an approach will involve the comparison with official wheat yield data at NUTS-3 level. [less ▲]

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See detailExperimental investigation of flow pattern and sediment deposition in rectangular shallow reservoirs
Dufresne, Matthieu; Dewals, Benjamin ULiege; Erpicum, Sébastien ULiege et al

in International Journal of Sediment Research (2010), 25(3), 258-270

This work involved the experimental investigation of flow pattern, preferential regions of deposition and trap efficiency as a function of the length of rectangular shallow reservoirs. Four flow patterns ... [more ▼]

This work involved the experimental investigation of flow pattern, preferential regions of deposition and trap efficiency as a function of the length of rectangular shallow reservoirs. Four flow patterns were identified (from longer to shorter reservoirs): an asymmetric flow with two reattachment points, an asymmetric flow with one reattachment point, an unstable flow, and a symmetric flow without any reattachment point. Using dye visualizations, the median value and the temporal variability of the reattachment lengths were precisely measured for the asymmetric flows. For each stable flow, sediment tests with plastic particles were carried out. The regions of deposition on the bed of the reservoir were clearly a function of the flow pattern. The transition from an asymmetric flow pattern to a symmetric flow pattern was responsible for an abrupt decrease of the trap efficiency; a number of regression laws were discussed to take it into account. [less ▲]

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See detailThe 2500 yr long paleoseismological record of the Hazar Lake, East Anatolian fault, Turkey
Hubert, Aurelia ULiege; Vanneste, K.; Cagatay, N et al

Conference (2010, September)

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See detailÉtude et développement de techniques de métrologie de déplacements en lumière cohérente en infrarouge thermique
Vandenrijt, Jean-François ULiege

Doctoral thesis (2010)

This thesis presents the works realised to apply ESPI and digital holography techniques at 10 µm for the monitoring of surface displacements of aerospace structures and space re- flectors. We consider ... [more ▼]

This thesis presents the works realised to apply ESPI and digital holography techniques at 10 µm for the monitoring of surface displacements of aerospace structures and space re- flectors. We consider objects with dimensions from a few tens of centimetres to more than one metre and with measurement ranges extending from a few micrometers to hundreds of micrometers. For specular surfaces where no diffusive coatings are allowed, we present the speckle pro- jection technique. We implement it in the special case of space reflectors. The use of a dif- fuser as the light source makes optical design much more simple and flexible than tradi- tional interferometric techniques. It allows use to consider its application on a wide range of form. We have also taken profit of the LWIR range to realise for the first time simultaneous dis- placement and temperature measurements with the same infrared detector. For this, we propose different computation techniques of the thermal image out of the phase shifted ESPI specklegram acquisitions. [less ▲]

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See detail4DCT EVALUATION OF THE RESPIRATORY-RELATED MOVEMENT OF THE BREAST USING SURGICAL CLIPS AS FIDUCIALS
JANVARY, Zsolt Levente ULiege; Broens, Audrey; MARTINIVE, Philippe ULiege et al

Poster (2010, September)

To explore the respiratory-related displacement of the tumour bed in patients undergoing breast conserving <br />surgery followed by external-beam radiotherapy, by using respiratory correlated imaging and ... [more ▼]

To explore the respiratory-related displacement of the tumour bed in patients undergoing breast conserving <br />surgery followed by external-beam radiotherapy, by using respiratory correlated imaging and surgical clips as fiducials. [less ▲]

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See detailRelevance of the resident diary method to map odour sources.
Nicolas, Jacques ULiege; Cors, Marie; Delva, Julien et al

in Chemical Engineering Transactions (2010, September), 23

A methodology based on the social participation through the use of resident diaries was applied to evaluate the odour annoyance in the surroundings of an industrial park in Belgium during one year. The ... [more ▼]

A methodology based on the social participation through the use of resident diaries was applied to evaluate the odour annoyance in the surroundings of an industrial park in Belgium during one year. The studied area covers about 8 km2 and includes13 potential odour emitting facilities. A network of 44 residents was implied in the survey, from which 19 were particularly considered for a detailed analysis. The questionnaire aimed at providing twice-daily an odour strength rating on a 6-level scale together with an odour qualifier. The fact that the response rate corresponding to "no-odour" was high (79%) is particularly discussed. Some tests are proposed to check the plausibility of the responses, the consistency within clusters of residents and the individual performance of respondents to discriminate among odour ratings. The odour rose is presented as an attractive and visual tool, particularly suited in the case of multi-source areas, to map the different odour emissions, to point out the more worrying ones, some others creating less annoyance and possible new unpredicted ones. The resident diary method proves to be very interesting, especially in the case of an industrial area, provided that validation checks are performed to insure the data reliability. [less ▲]

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