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See detailThrough the Wormhole: Tracking Invisible MPLS Tunnels
Vanaubel, Yves ULiege; Mérindol, Pascal; Pansiot, Jean-Jacques et al

in ACM Internet Measurement Conference (2017, November)

For years, Internet topology research has been conducted through active measurement. For instance, CAIDA builds router level topologies on top of IP level traces obtained with traceroute. The resulting ... [more ▼]

For years, Internet topology research has been conducted through active measurement. For instance, CAIDA builds router level topologies on top of IP level traces obtained with traceroute. The resulting graphs contain a significant amount of nodes with a very large degree, often exceeding the actual number of interfaces of a router. Although this property may result from inaccurate alias resolution, we believe that opaque MPLS clouds made of invisible tunnels are the main cause. Using Layer-2 technologies such as MPLS, routers can be configured to hide internal IP hops from traceroute. Consequently, an entry point of an MPLS network appears as the neighbor of all exit points and the whole Layer-3 network turns into a dense mesh of high degree nodes. This paper tackles three problems: the revelation of IP hops hidden by MPLS tunnels, the MPLS deployment underestimation, and the overestimation of high degree nodes. We develop new measurement techniques able to reveal the presence and content of invisible MPLS tunnels. We assess them through emulation and cross-validation and perform a large-scale measurement campaign targeting suspicious networks on which we apply statistical analysis. Finally, based on our dataset, we look at basic graph properties impacted by invisible tunnels. [less ▲]

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See detailCoordinated Supervisory Control of Multi-Terminal HVDC Grids: a Model Predictive Control Approach
Papangelis, Lampros ULiege; Debry, Marie-Sophie; Panciatici, Patrick et al

in IEEE Transactions on Power Systems (2017), 32(6), 4673-4683

A coordinated supervisory control scheme for future multi-terminal High-Voltage Direct-Current (HVDC) grids is proposed. The purpose is to supervise the grid and take appropriate actions to ensure power ... [more ▼]

A coordinated supervisory control scheme for future multi-terminal High-Voltage Direct-Current (HVDC) grids is proposed. The purpose is to supervise the grid and take appropriate actions to ensure power balance and prevent or remove voltage or current limit violations. First, using DC current and voltage measurements, the power references of the various Voltage Sources Converters (VSC) are updated according to participation factors. Next, the setpoints of the converters are smoothly adjusted to track those power references, while avoiding or correcting limit violations. The latter function resorts to Model Predictive Control and a sensitivity model of the system. The efficiency of the proposed scheme has been tested through dynamic simulations of a five-terminal HVDC grid interconnecting two asynchronous AC areas and a wind farm. [less ▲]

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See detailCaractérisations phénotypiques des populations de pintades (Numida meleagris) locales élevées au Bénin
Houndonougbo, Pascal ULiege

Doctoral thesis (2017)

La pintade (Numida meleagris) est une volaille d’origine africaine. Son élevage est répandu en Afrique subsaharienne dans un système traditionnel où plusieurs variétés sont élevées en liberté. Ces ... [more ▼]

La pintade (Numida meleagris) est une volaille d’origine africaine. Son élevage est répandu en Afrique subsaharienne dans un système traditionnel où plusieurs variétés sont élevées en liberté. Ces variétés qui diffèrent par le coloris de leur plumage sont très peu caractérisées. Au nord Bénin, l’élevage avicole moderne est peu rencontré et la pintade constitue la pondeuse d’œufs de table dans cette région. Mais, la mortalité élevée, la faible productivité de la pintade locale limitent fortement le développement de son élevage. Il est alors nécessaire de caractériser les variétés de pintades élevées pour mieux les valoriser dans un système amélioré. L’objectif de cette thèse est de caractériser phénotypiquement la population de pintade locale élevée au Bénin afin de mieux valoriser l’espèce dans des programmes d’amélioration et de développement du secteur avicole national. Une revue bibliographique (Article de synthèse) a permis de réaliser l’état des lieux de l’élevage de pintade au Bénin et de mieux orienter nos travaux pour une bonne caractérisation des variétés élevées. L’existence de plusieurs variétés dans les élevages a été soulignée dans la revue bibliographique et nous a amené à des enquêtes et un suivi des élevages de pintades en milieu villageois. Ces enquêtes et suivi nous ont permis de caractériser les pintades locales dans leur milieu d’élevage selon les dire des éleveurs. Ils nous ont aussi permis de dégager selon les éleveurs, les objectifs de production, l’importance socio-économique et culturelle des variétés élevées. L’influence de l’alimentation sur les performances technico-économiques des pintades locales a été soulignée dans l’Article de synthèse et l’Article I. Cette influence a été abordée en évaluant l’influence de l’alimentation sur le potentiel de croissance de la pintade locale en station (Article II). Enfin, des travaux ont été réalisés en station pour mieux caractériser les variétés de pintades rencontrées dans les élevages sur le plan morphologique, performances de croissance et de reproduction (Articles III, IV et V). Ces différents travaux nous ont permis de recenser les différentes variétés de pintades locales élevées au Bénin, les objectifs d’élevage des éleveurs ainsi que quelques difficultés liées au développement de cet élevage. Ces travaux nous ont surtout permis de mieux caractériser les variétés rencontrées. Cette caractérisation pourrait être valorisée pour améliorer la productivité des variétés par sélection. [less ▲]

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See detailIndexing grey multilingual literature in General Practice in the era of Semantic Web
Jamoulle, Marc ULiege; Resnick, Melissa; Ittoo, Ashwin ULiege et al

in The Grey Journal (2017, October 23)

voir abstract ci-dessous

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See detailUpscaling winter wheat above-ground biomass measurements using multispectral imagery and 3D data from unmanned aerial vehicle
Michez, Adrien ULiege; Bauwens, Sébastien ULiege; Heinesch, Bernard ULiege et al

Poster (2017, October 20)

Field measurements in the ICOS program are spatially limited whereas the monitored gas fluxes may have a large footprint. Aerial remote sensing has the advantage to monitor large areas. The main goal of ... [more ▼]

Field measurements in the ICOS program are spatially limited whereas the monitored gas fluxes may have a large footprint. Aerial remote sensing has the advantage to monitor large areas. The main goal of our research was to test the potential of unmanned aerial vehicles (UAV) to upscale parameters monitored through the ICOS program. In this study, we specifically focus on above-ground biomass (AGB) monitoring in a winter wheat crop. We used a octocopter drone (X frame type) to acquire a time series over the crop growing season (8 flights from the 14th of February 2017 to the 7th of July 2017) of multispectral imagery covering the ICOS candidate station of Lonzée (Wallonia, Belgium) and the surrounding field crop areas (ca. 0.25 km² per flight). The multispectral camera provides spectral information on the green (550 +/- 50 nm), red (660 +/- 50 nm), near infrared (735 +/- 50 nm) and red-edge (790 +/- 10 nm) wavelengths bands. The UAV also brought an off-the-shelf high resolution (20 Mpx) RGB camera to derive accurate 3D data. We performed a photogrammetric 3D reconstruction of the acquired imagery for every flight survey. The images provided by the RGB sensor (Sony RX100) were used to produce a high spatial resolution Digital Surface Model (0.05 m) and the images acquired by the multispectral sensor were used to derive reflectance maps (0.1 m) in the four wavelengths bands. The four reflectance layers were combined to produce two straight-forward vegetation indices (Normalized Difference Vegetation Index and Green NDVI). The photogrammetric DSM’s were combined to a LiDAR Digital Terrain Model (public database, survey in winter 2013) to produce Crop Height Models (CHM) of the study area. We used multiple linear regressions modelling in order to predict the AGB of the field crop monitored by the ICOS station of Lonzée with UAV imagery. AGB=a+b*GNDVI+c*NDVI+d *CHM The field crop data were provided by the ICOS program and by field research conducted in experimental field crops close to the flux tower. The field sampling consisted in destructive samples of the crop which were weighted after drying. For each field sample, an associated area was computed based on the outdistance sowing and the number of sampled crops in order to compute an AGB per area unit (t / Ha). Each AGB field estimation was associated to the closest flight date to build a multi date model presenting good performances (r² = 0.85, RMSE = 2.3 t/Ha). We used the same modelling approach to adjust a single date model to derive a predicted AGB map for the 7th of July. The performance of the single date model is lower but still highlights the biomass variation within the crop (r² = 0.71, RMSE = 1.9 t/Ha). The predicted AGB map displays a high spatial heterogeneity with some spatial patterns. Locally low AGB values are found along two old pedestrian whereas higher AGB values can be associated to areas which were sprayed twice (in-between two tractor tracks). Our results highlight the potential of UAV multispectral imagery to monitor the AGB variation within the footprint of the flux tower and highlight the need for repeated field sampling with a precise geolocation to improve the matching between the flight and the field surveys. [less ▲]

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See detailEvaluation of the Xpert®GBS LB test (Cepheid) performed on antenatal screening LIM enrichment broth for detection of Streptococcus agalactiae or group B streptococcus, compared to the reference culture method.
MEEX, Cécile ULiege; DUPONT, Audrey; SACHELI, Rosalie ULiege et al

Conference (2017, October 19)

PCR, performed on LIM enrichment broth compared wit the reference method, that is subculture on selective differential agar performed from the same incubated Lim broth inoculated with a vagino-rectal swab ... [more ▼]

PCR, performed on LIM enrichment broth compared wit the reference method, that is subculture on selective differential agar performed from the same incubated Lim broth inoculated with a vagino-rectal swab collected at 35-37 weeks’ gestation. Material/methods: During an 8-months period in 2015-2016, series of consecutive vagino/rectal swabs collected for antenatal GBS screening (at the university hospital of Liege, Belgium) were plated first on Granada agar and then inoculated in selective enrichment LIM broth. The incubated broth was further sub-cultured on Granada and Biorad StrepBselect agars. Moreover, a sterile swab immersed in the same incubated broth was further analyzed by a real-time PCR targeting GBS using the Xpert®GBS LB test on the GeneXpert® system (Cepheid). Results: Among the 288 antenatal screenings included in the study, 48 (16.7%) were positive for GBS using the culture reference method and 51 Xpert®GBS LB test were positive (17.7%), includin the 48 samples positive in culture and 3 additional specimens for witch culture remained negative. Considering the enriched culture as the gold standard, the sensitivity and specificity of the Xpert®GBS LB test were 100% and 98.8% respectively. Conclusions: The Xpert®GBS LB test performed on incubated LIM broth is at least as efficient as selective enriched culture for antenatal screening of GBS. The turnaround-time and hands-on-ti are much shorter for the Xpert® GBS LB but it is more expensive than culture method, which may limit its use. [less ▲]

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See detailAn open question about diametral dimensions
Demeulenaere, Loïc ULiege

Conference (2017, October 19)

The diametral dimension is a topological invariant which characterizes Schwartz and nuclear spaces. However, there exists another diametral dimension which was conjectured by Bessaga, Mityagin, Pełczynski ... [more ▼]

The diametral dimension is a topological invariant which characterizes Schwartz and nuclear spaces. However, there exists another diametral dimension which was conjectured by Bessaga, Mityagin, Pełczynski, and Rolewicz to be equal to the first one in Fréchet spaces. In this talk, we describe some conditions which assure the equality of the two diametral dimensions in metrizable locally convex spaces. Besides, we explain why such an equality is generally impossible in non-metrizable spaces. [less ▲]

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See detailIndividuality Through Relatedness: A Leibnizian Framework for Quantum Mechanics
Dony, Arthur ULiege

Conference (2017, October 18)

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See detailEffect of including a gas layer on the gel formation process during the drying of a polymer solution
Rabani, Ramin ULiege; Machrafi, Hatim ULiege; Dauby, Pierre ULiege

in The European Physical Journal E (2017), 40(89), 11579-3

In this paper, we study the influence of the upper gas layer on the drying and gelation of a polymer solution. The gel is formed due to the evaporation of the binary solution into (inert) air. A one ... [more ▼]

In this paper, we study the influence of the upper gas layer on the drying and gelation of a polymer solution. The gel is formed due to the evaporation of the binary solution into (inert) air. A one dimensional model is proposed, where the evaporation flux is more realistically described than in previous studies. The approach is based on general thermodynamic principles. A composition-dependent diffusion coefficient is used in the liquid phase and the local equilibrium hypothesis is introduced at the interface to describe the evaporation process. The results show that the high thickness of the gas layer reduces evaporation, thus leading to longer drying times. Our model is also compared with more phenomenological descriptions of evaporation, for which the mass flux through the interface is described by the introduction of a Peclet number. A global agreement is found for appropriate values of the Peclet numbers and our model can thus be considered as a tool allowing to link the value of the empirical Peclet number to the physics of the gas phase. Finally, in contrast with other models, our approach emphasizes the possibility of very fast gelation at the interface, which could prevent all Marangoni convection during the drying process. [less ▲]

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See detailWalking droplets above cavities
Filoux, Boris ULiege

Doctoral thesis (2017)

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See detailImpact of Financial Assumptions on the Cost Optimality towards Nearly Zero Energy Buildings- A case study
Hamdy, Mohamed; Siren, Kai; Attia, Shady ULiege

in Energy and Buildings (2017), 153

The energy efficiency challenge in Europe is mainly concerned with existing buildings and the investment scenarios to implement deep renovations. The cost-optimal approach imposed on EU-Member states by ... [more ▼]

The energy efficiency challenge in Europe is mainly concerned with existing buildings and the investment scenarios to implement deep renovations. The cost-optimal approach imposed on EU-Member states by the European Energy Performance of Buildings Directive aims to identify the investment gap and challenges to transform existing buildings into nearly Zero Energy Buildings (nZEBs). The investment gap is function of several volatile financial parameters including discount rate (r), developing of energy price (e), decline rate of technology price (d), as well as nZEB’s incentives like feed-in-tariff (FiT) and investment grant (iG). In this context, the decision making process of individuals or investment institutions is hindered by complexity and uncertainty. In order to assist the decision making process and improve the visibility of financial energy benefits, a novel optimization-based parametric analysis scheme (OptnZEB-I) is developed. The scheme is designed to investigate a large number of economic scenarios (i.e., combinations of financial assumptions) in a short computational time while a holistic optimization approach is adopting for exploring all possible design options including energy conservation measures (ESMs); renewable energy sources (RETs) and mechanical systems (Sys). For demonstration, the scheme is applied to analyse the impact of several financial parameters on the cost-optimal energy performance level (CO-EPL) of a single family house in Finland. In line with the EU-directive, a large number of possible design options (∼3 × 109million) are optimized for 4608 cases of economic scenarios. The results of the address case study show that, in average, the CO-EPL ranges from 90 to 160 [kWh/m2]. The range has most frequent value of 145 kWh/m2. The CO-EPL is significantly sensitive to the e, f, then i, respectively. Less sensitivity is found to the other financial parameters. The robustness of the optimization results are verified by solving the addressed design problem by using four different optimization algorithms (i.e., pattern search, interior-point, simulated annealing and genetic algorithms). [less ▲]

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See detailInventory of Beekeeping in the Algerian north (Tizi-ouzou and Bejaia)
Yahi, Krimou; Touazi, Leghel; Kaidi, Rachid et al

Poster (2017, October 13)

The objective of this study is to make an inventory of the honey production in the counties of Bejaia and Tizi-Ouzou in northeastern Algeria. To achieve this, a survey was carried out on 31 beekeepers (14 ... [more ▼]

The objective of this study is to make an inventory of the honey production in the counties of Bejaia and Tizi-Ouzou in northeastern Algeria. To achieve this, a survey was carried out on 31 beekeepers (14 in Bejaia and 17 in Tizi-Ouzou). The survey shows a social, cultural and religious role for 61.29% of the beekeepers. The beekeeping is primarily held by men (93.55%). It is the basic source of income for 64.52% of the respondents. The average age of the beekeepers is 42.90years (Min-Max: 28-67 years, Median: 40.5 years). The main products of the hive are honey (100%), swarms (16.13%), royal jelly (9.68%) and propolis (9.68%). The average honey production per hive is 7.70kg (Min-Max: 0.4-15kg hives, Median: 10kg). The average number of hives per beekeeper is 42.20 hives (Min-Max: 3-300 hives, Median: 17.50 hives). The average selling price of one kg of honey is 4000.00 DA / kg (Min-Max: 2000-5000DA; Median: 4000DA). The phenotype of the bee reported by 74.19% of the surveys is of small size with a long body and dark pigmentation corresponding to the breed “Apis mellifera intermissa”. Two apiculturists described another phenotype corresponding to the “Apis mellifera major”. The factors behind the motivations for beekeeping are consumption of honey (100%), income generation (90.32%), hobby (58.06%) and conservation of biodiversity (22.58%). The multiple constraints associated with several diseases, notably Varroase (mentioned by 80.65% of beekeepers), cause difficulties for the breeders. Thus they cannot profit maximum from beekeeping. Other constraints which were reported are; forest fires (35.48%), wasps (32.26%), absence of beekeeping professionals or technicians (29.03%), harsh and cold winters with snow (19.35%), high density of hives in the region (16.13%) and uncontrolled spreading of pesticides and crop protection products at farms (12.90%). The economic situation of the Algerian beekeepers can be optimized by improving the production potential of the local bees. [less ▲]

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See detailQuality assessment of marketed eggs in Hanoi (Vietnam)
Moula, Nassim ULiege; Luc, Do Duc; Bo, H. X. et al

Poster (2017, October 13)

Poultry farming is the first sector of livestock that has been industrialized. The poultry sector plays an important role in the GDP of Vietnam. It is the second largest livestock after the pig livestock ... [more ▼]

Poultry farming is the first sector of livestock that has been industrialized. The poultry sector plays an important role in the GDP of Vietnam. It is the second largest livestock after the pig livestock. The production and consumption of eggs in Vietnam is estimated as 5.64 billion and 102.6 eggs per person per year respectively. The aim of this study was to assess the quality of eggs in relation to the chicken breed and different marketing channels in Hanoi, Vietnam. In total, 431 chicken eggs were purchased from four different marketing channels in Hanoi, including households (89 eggs), supermarkets (152 eggs), public markets (130 eggs) and small grocery stores (50 eggs). Out of the 431 above-mentioned eggs, 119 eggs came from the commercial chicken breeds and 312 eggs from traditional local breeds. The quality of eggs for a consumer is represented by its cleanliness, nutritional quality, freshness, and price. A series of measurements is carried out just after their purchase. According to the breed and the marketing channel, highly significant differences (P <0.05) were found in the freshness of the eggs (Haugh units), egg prices, eggs weight, egg shell, the white and the yolk of the egg. Though the chicken breed and marketing channels do not significantly affect (P> 0.05) the freshness of the eggs, however, they have a significant effect (P <0.05) on the size of the eggs marketed in Hanoi. The results of this study show an important diversity in marketing channels and marketed eggs in Hanoi. [less ▲]

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See detailMédium et discours scientifique. La chronique comme genre de la recherche ?
Mayeur, Ingrid ULiege

Conference (2017, October 13)

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See detailComparison of the effects of Opuntia ficus-indica powder on growth performance and serum parameters of the Broiler Chicken in Algeria
Moula, Nassim ULiege; Humbel, Maïlis ULiege; Leterrier, Mélanie ULiege et al

Poster (2017, October 13)

In Algeria, the ingredients used in the broiler feed are exclusively imported from abroad, which affects negatively the production cost of the chicken meat and its sale price in the market at national ... [more ▼]

In Algeria, the ingredients used in the broiler feed are exclusively imported from abroad, which affects negatively the production cost of the chicken meat and its sale price in the market at national level. Because of the wide diversity in soil and climate, Algeria has a substantial number of plants which can be used in animal feed. This work is part of the valuation of the feed potential of the barbaric fig tree, widely present in the Algerian rural landscape, for the broiler chicken. The Opuntia ficus-indica is known for its edible fruits and for use of its fleshy leaves or “racquets” as fodder especially during periods of drought. It is also used to control the water and wind erosion as well as for the protection and improvement of soil fertility in arid and semi-arid regions. The aim of this study was to measure the effects of Opuntia ficus-indica powder on growth performance, serum composition and carcass yield of broiler chickens. The experiments were performed in a private poultry farm in the Chemini region (Wilaya de Bejaia). In this study, 120 Ross-308 day-old male chicks were monitored. They were divided in 3 groups (Group 1, 2 and 3) according to the specific diet (4 x 10 chicks / group). The group 1 was offered commercial feed. The group 2 and group 3 were offered the same commercial feed as group 1 but 5% and 10% of the commercial feed was replaced by the Opuntia ficus-indica powder respectively. The Opuntia ficus-indica powder did not show any negative effect (p>0.05) on the final body-weight, average daily gain and carcass yield. However, it decreased (p<0.05) the biochemical parameters -blood concentration- (plasma glucose, uremia, cholesterol and triglycerides). In conclusion, the Opuntia ficus-indica powder has the potential to be used in poultry feed to reduce the cost of broiler feed in Algeria [less ▲]

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See detailGround-based FTIR retrievals of SF6 at Réunion Island
Zhou, M.; Langerock, B.; Vigouroux, C. et al

in Atmospheric Measurement Techniques. Papers in Open Discussion (2017), 2017

SF6 total columns are successfully retrieved from FTIR measurements (Saint Denis and Maïdo) at Réunion Island (21 S, 55 E) between 2004-2016 using the SFIT4 algorithm: the retrieval strategy and the error ... [more ▼]

SF6 total columns are successfully retrieved from FTIR measurements (Saint Denis and Maïdo) at Réunion Island (21 S, 55 E) between 2004-2016 using the SFIT4 algorithm: the retrieval strategy and the error budget are presented. The FTIR SF6 retrieval has independent information in only one individual layer, covering the whole troposphere and the lower stratosphere. The trend of SF6 is analysed based on the FTIR retrieved dry air column-averaged mole fractions (XSF6 ) at Réunion Island, the in-situ measurements at America Samoa (SMO) and the collocated satellite measurements (MIPAS and ACE-FTS) in the southern tropics. The SF6 annual growth rate from FTIR retrievals is 0.265±0.013 pptv/year for 2004–2016, which is slightly weaker than that from the SMO in-situ measurements (0.285±0.002 pptv/year) for the same time period. The SF6 trend in the troposphere from MIPAS and ACE-FTS observations is also close to the ones from the FTIR retrievals and the SMO in-situ measurements. [less ▲]

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See detailThe Vacuum UV Photoabsorption Spectrum of the Geminal Dichloroethylene (1,1-C2H2Cl2) in the 5-20 eV Range. A Vibrational Analysis of the Valence and Rydberg States.
Locht, Robert ULiege; Dehareng, Dominique; Leyh, Bernard ULiege

in Journal of Physics Communications (2017), 1

The vacuum UV photoabsorption spectrum of 1,1-C2H2Cl2 is presented and discussed in detail in the 6 - 20 eV photon energy range. The broad band observed at 6.488 eV includes the 2b1()→σ*, 2b1()→ ... [more ▼]

The vacuum UV photoabsorption spectrum of 1,1-C2H2Cl2 is presented and discussed in detail in the 6 - 20 eV photon energy range. The broad band observed at 6.488 eV includes the 2b1()→σ*, 2b1()→* valence transitions and the 2b1()→3s Rydberg transitions. A quantum chemical calculation analysis is proposed and applied to the intertwined vibrational structure belonging to these transitions. For the →σ* and →* transitions short vibrational progressions are observed, analyzed and tentatively assigned. The →3s Rydberg transition is characterized by a single progression starting at 6.746 eV. The fine structure observed between 7.5 eV and 10.1 eV has been analyzed in terms of vibronic transitions to ns- (δ= 0.89), np- (δ= 0.59 and 0.37) and nd-type (δ= 0.16) Rydberg states all converging to the 1,1-C2H2Cl2+( 2B1) ionic ground state. The vibrational structure analysis excitation leads to the following wavenumbers: ω2≈ 1310 cm-1 (162 meV), ω4≈ 650 cm-1 (81 meV) and ω5≈ 290 cm-1 (37 meV). These modes can be assigned to the C=C stretching, to the symmetric C-Cl stretching and to the symmetric Cl-C-Cl bending vibrations respectively. By the same way, eight other Rydberg states were analyzed. For the first time the vacuum UV spectrum of 1,1-C2H2Cl2 has been recorded in the 10 eV-20 eV range, revealing intense broad bands which are assigned to transitions to Rydberg states converging to excited states of 1,1-C2H2Cl2+. Assignments are also proposed for the vibrational excitations observed in this range. [less ▲]

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See detailAdvanced porosity-based models to assess the influence of urban layouts on inundation flows and impact of urban evolution on flood damage
Bruwier, Martin ULiege

Doctoral thesis (2017)

Worldwide, flood risk is expected to increase over the 21st century due to the combined effect of climate and land use changes. However, while the impact of climate change on future flood risk was ... [more ▼]

Worldwide, flood risk is expected to increase over the 21st century due to the combined effect of climate and land use changes. However, while the impact of climate change on future flood risk was extensively studied, the effects of urbanization remain unclear. The goal of this PhD thesis is to contribute to a better understanding of the influence of future urban development on changes in inundation flows as well as on the related damage. First, an original porosity-based model was developed, which enables efficient computation of urban flooding. It uses anisotropic porosity parameters to reproduce the influence of subgrid-scale obstacles on the flow. An original merging technique was implemented to optimize the computational efficiency in the presence of low values of the storage porosity parameter. Compared to a standard inundation model, the developed model enables speedup factors of the order of 100, while keeping the error on the flow variables at a few percent. Second, we systematically investigated how the layout of buildings located in floodplains influences the inundation characteristics for a long-duration flood scenario. The anisotropic porosity-based model was used to compute the flow variables for 2,000 alternative urban patterns. Correlations between the computed water depths and the urban characteristics reveal which features of the layout of buildings influences most the severity of urban flooding. In particular, the results suggest how the hydraulic effect of new urban development can be effectively mitigated by a suitable location of the buildings preserving a higher flow conveyance at the district-scale. This result provides guidance for more flood-proof urban developments. Finally, we evaluated the evolution of future flood damage as a result of urbanization along all the main rivers in the Walloon region, Belgium. The study was conducted at the regional level using detailed hydraulic results (resolution of 2 to 5 m). Despite high uncertainties in the considered urbanization scenarios, involving both urban expansion and densification, robust conclusions could be drawn, such as the overwhelming influence of banning new developments in flood-prone areas compared to the other tested facets of urban planning policy. [less ▲]

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