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See detailUse of GEOS-Chem for the interpretation of long-term FTIR measurements at the Jungfraujoch and other NDACC sites
Mahieu, Emmanuel ULg; Bovy, Benoît ULg; Bader, Whitney ULg et al

Poster (2015, May 04)

We present recent and ongoing investigations using 3D CTM GEOS-Chem model simulations for the interpretation of long-term FTIR measurements performed at selected NDACC sites.

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See detailThe crucial role of soil when modelling the impact of climate change on crop production
Basso, Bruno; Dumont, Benjamin ULg; Shcherbak, Iurii et al

in Shirmohammadi, Adel; Bosch, David; Muñoz-Carpena, Rafa (Eds.) Proceedings of the 1st ASABE Climate Change Symposium - Adaptation and Mitigation (2015, May 03)

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See detailVariability in the super-Earth 55 Cnc e
Demory, Brice-Olivier; Gillon, Michaël ULg; Madhusudhan, Nikku et al

E-print/Working paper (2015)

Considerable progress has been made in recent years in observations of atmospheric signatures of giant exoplanets, but processes in rocky exoplanets remain largely unknown due to major challenges in ... [more ▼]

Considerable progress has been made in recent years in observations of atmospheric signatures of giant exoplanets, but processes in rocky exoplanets remain largely unknown due to major challenges in observing small planets. Numerous efforts to observe spectra of super-Earths, exoplanets with masses of 1-10 Earth masses, have thus far revealed only featureless spectra. In this paper we report a 4-$\sigma$ detection of variability in the dayside thermal emission from the transiting super-Earth 55 Cancri e. Dedicated space-based monitoring of the planet in the mid-infrared over eight eclipses revealed the thermal emission from its dayside atmosphere varying by a factor 3.7 between 2012 and 2013. The amplitude and trend of the variability are not explained by potential influence of star spots or by local thermal or compositional changes in the atmosphere over the short span of the observations. The possibility of large scale surface activity due to strong tidal interactions possibly similar to Io, or the presence of circumstellar/circumplanetary material appear plausible and motivate future long-term monitoring of the planet. [less ▲]

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See detailControlled synthesis of ethylene-vinyl acetate based copolymers by organometallic mediated radical polymerization
Demarteau, Jérémy ULg; Kermagoret, Anthony ULg; Jérôme, Christine ULg et al

in Matyjaszewski, Krzysztof; Sumerlin, Brent S.; Tsarevsky, Nicolay V. (Eds.) et al Controlled Radical Polymerization: Materials (2015)

The controlled radical copolymerization of ethylene (E) and vinyl acetate (VAc) is further investigated by organometallic- mediated radical polymerization (OMRP) using Co(acac)2 as controlling agent at ... [more ▼]

The controlled radical copolymerization of ethylene (E) and vinyl acetate (VAc) is further investigated by organometallic- mediated radical polymerization (OMRP) using Co(acac)2 as controlling agent at ethylene pressure up to 100 bar. The effect of ethylene pressure on kinetics, level of control and copolymer composition, is discussed. Ethylene-Vinyl Acetate copolymers (EVAs) with low dispersities and ethylene content reaching 57 mol% are notably reported. This work also successfully addresses the precision design of EVA-containing block copolymers, i.e. PVAc-block-EVA. In this case, the order of the synthesis of the blocks is a key parameter. The “PVAc-first” strategy is by far more practical and efficient. [less ▲]

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See detailThe Kambarata 2 blast-fill dam, Kyrgyz Republic: blast event, geophysical monitoring and dam structure modelling
Havenith, Hans-Balder ULg; Torgoev, Isakbek; Torgoev, Almazbek ULg et al

in Geoenvironmental Disasters (2015), 2(1), 1-15

Abstract Background The blast-and earth-fill dam of the Kambarata 2 hydropower station is situated in the seismically active Central Tien Shan region of the Kyrgyz Republic. More than 70% of the dam ... [more ▼]

Abstract Background The blast-and earth-fill dam of the Kambarata 2 hydropower station is situated in the seismically active Central Tien Shan region of the Kyrgyz Republic. More than 70% of the dam volume was produced during a blast event on December 22, 2009. In 2010– 2011, dam construction was completed after earth filling on top of the blasted material and installing concrete and clay screens together with bentonite grouts. A geophysical survey had been completed in 2012–2013, mainly to monitor the resistivities inside the dam. ... [less ▲]

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See detail'Een lent van vaerzen' als letterkundig spiegelkabinet
Steyaert, Kris ULg

in Arabesken: Tijdschrift van het Louis Couperus Genootschap (2015)

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See detailValid inequalities for the single arc design problem with set-ups
Agra, Agostinho; Doostmohammadi, Mahdi; Louveaux, Quentin ULg

in Discrete Optimization (2015), 16

We consider a mixed integer set which generalizes two well-known sets: the single node fixed- charge network set and the single arc design set. Such set arises as a relaxation of feasible sets of general ... [more ▼]

We consider a mixed integer set which generalizes two well-known sets: the single node fixed- charge network set and the single arc design set. Such set arises as a relaxation of feasible sets of general mixed integer problems such as lot-sizing and network design problems. We derive several families of valid inequalities that, in particular, generalize the arc resid- ual capacity inequalities and the flow cover inequalities. For the constant capacitated case we provide an extended compact formulation and give a partial description of the convex hull in the original space which is exact under a certain condition. By lifting some basic inequalities we provide some insight on the difficulty of obtaining such a full polyhedral description for the constant capacitated case. Preliminary computational results are presented. [less ▲]

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See detailTesting of a Spacecraft Structure with Non-Smooth Nonlinearities
Renson, Ludovic ULg; Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg

Conference (2015, May)

The dynamics of the SmallSat, a real-life spacecraft possessing a complex isolation device with multiple nonsmooth nonlinearities is investigated. Experiments show that nonlinearities induce modal ... [more ▼]

The dynamics of the SmallSat, a real-life spacecraft possessing a complex isolation device with multiple nonsmooth nonlinearities is investigated. Experiments show that nonlinearities induce modal interactions between modes with non-commensurate linear frequencies. A model of the structure with a simplified description of the nonlinear connections is first built using techniques available in industry. Numerical continuation is then exploited to compute nonlinear normal modes and uncover interaction phenomena that can jeopardize the structural integrity. [less ▲]

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See detailPerformance-Based Aid: Why it will probably not meet promises
Paul, Elisabeth ULg

in Development Policy Review (2015), 33(3),

Performance-based aid (PBA) is increasingly advocated as a way to improve development aid effectiveness through resolving incentive issues inherent in aid relationships. Some donors use PBA together with ... [more ▼]

Performance-based aid (PBA) is increasingly advocated as a way to improve development aid effectiveness through resolving incentive issues inherent in aid relationships. Some donors use PBA together with performance-based financing arrangements within partner countries. Expectations from PBA are high – yet, while its rationale may look appealing, it is grounded on a restrictive model and flawed when taking account of real-world context. A number of problems associated to PBA have already been advanced as jeopardising its success. More fundamentally, one may question the mere appropriateness of PBA to provide incentives all along the chain from recipient governments to those who are supposed to produce results. Thus believing that PBA can have a mechanistic trickle-down incentive effect seems an illusion. [less ▲]

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See detailAdapting Nitrogen management to the increasing climatic uncertainty
Dumont, Benjamin ULg; Basso, Bruno; Bodson, Bernard ULg et al

in Shirmohammadi, Adel; Bosch, David; Muñoz-Carpena, Rafa (Eds.) Proceedings of the 1st ASABE Climate Change Symposium - Adaptation and Mitigation (2015, May)

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See detailLinear and propeller-like fluoro-isoindigo based donor–acceptor small molecules for organic solar cells
Ouhib, Farid ULg; Tomassetti, Mirco ULg; Dierckx, Wauter et al

in Organic Electronics (2015), 20

Two donor–acceptor type fluoro-isoindigo based small molecule semiconductors are syn- thesized and their optical, electrochemical, thermal, and charge transport properties are investigated. The two ... [more ▼]

Two donor–acceptor type fluoro-isoindigo based small molecule semiconductors are syn- thesized and their optical, electrochemical, thermal, and charge transport properties are investigated. The two molecular chromophores differ by their architecture, linear (M1) vs propeller-like (M2). Both molecules present a broad absorption in the visible range and a low optical HOMO–LUMO gap (?1.6 eV). AFM images of solution-processed thin films show that the trigonal molecule M2 forms highly oriented fibrils after a few seconds of solvent vapor annealing. The materials are evaluated as electron donor components in bulk heterojunction organic solar cells using PC61BM as the electron acceptor. The devices based on the propeller-like molecule M2 exhibit a high open-circuit voltage (around 1.0 V) and a power conversion efficiency of 2.23%. [less ▲]

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See detailFractured bedrock investigation by using high-resolution borehole images and the Distributed Temperature Sensing technique
Radioti, Georgia ULg; Delvoie, Simon ULg; Radu, Jean-Pol ULg et al

in ISRM Congress 2015 Proceedings - Int’l Symposium on Rock Mechanics (2015, May)

In order to investigate the fracturing of the bedrock and its possible heterogeneous distribution in situ, four boreholes equipped with double-U geothermal pipes of 100 m long were installed on the campus ... [more ▼]

In order to investigate the fracturing of the bedrock and its possible heterogeneous distribution in situ, four boreholes equipped with double-U geothermal pipes of 100 m long were installed on the campus of the University of Liege (Liege, Belgium) over a surface area of 32 m². The bedrock, which starts at a depth approximately of 8 m, is quite fractured and consists mainly of siltstone and shale interbedded with sandstone. Different geophysical methods are applied at two different phases, after drilling the boreholes and after injecting the grouting material. The first approach consists in lowering an ultrasonic borehole imager (borehole televiewer; Zemanek, Glenn, Norton, & Caldwell, 1970), an instrument that acts as an ultrasonic transducer and receiver, into the boreholes to obtain high-resolution, continuous images with 360° coverage of the local geology and fracturing. Moreover gamma-ray logs of the four boreholes are obtained and inclinometry is conducted. After drilling the boreholes fiber optic cables are attached along the pipe loops and the double-U pipes are installed inside the boreholes. Then the grouting material is injected. The second approach consists in measuring the temperature along the fibers by applying the Distributed Temperature Sensing technique (Soto, Sahu, Faralli, Bolognini, Di Pasquale, Nebendahl, & Rueck, 2007). A laser pulse is injected into the optical fiber and the temperature along the fiber is determined by the intensity of Raman stokes and anti-stokes reemitted signals. Temperature evolution is measured during hardening of the grouting material. Local maxima of the temperature curve are probably due to a local lower thermal conductivity and/or a local larger quantity of grouting material due to gathering of fractures. A detailed fracture characterisation (position, opening, orientation, dip angle) is obtained based on the acoustic signal travel time and amplitude. The fractures are characterised by the same dipping and orientation but significantly vary in number and location in the four boreholes, despite the close distance between them. Gamma-ray data and observation of the cuttings during drilling result in rock identification through depth as well as in determination of the layer dipping. The inclination of the four boreholes tends to be perpendicular to the dipping. The combination of the two geophysical methods as presented provides information useful for the hydro-thermo-mechanical behaviour of the bedrock. The contribution of the thermal behaviour of borehole heat exchangers to bedrock investigation will be further studied by conducting Distributed Thermal Response tests (Fujii, Okubo, & Itoi, 2006). During the tests we will measure the temperature variation thanks to the installed fiber optics. These data will allow us to correlate any anisotropic thermal behaviour to the geological characteristics. The available information could be used for a detailed numerical model. [less ▲]

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