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See detailMulti-frequency passive non-linear targeted energy transfers in systems of couples oscillators
Tsakirtzis, Stylianos; Panagopoulos, Panagiotis; Kerschen, Gaëtan ULg et al

in 5th GRACM International Congress on Computational Mechanics, Limassol, 2005 (2005, June)

We study the dynamics of a system of coupled linear oscillators with a multi-DOF end attachment with essential (nonlinearizable) stiffness nonlinearities. We show numerically that the multi-DOF attachment ... [more ▼]

We study the dynamics of a system of coupled linear oscillators with a multi-DOF end attachment with essential (nonlinearizable) stiffness nonlinearities. We show numerically that the multi-DOF attachment with damping can passively absorb broadband energy from the linear system in a one-way, irreversible fashion, acting in essence as nonlinear energy sink (NES). Strong passive targeted energy transfer from the linear to the nonlinear subsystem is possible, over wide frequency and energy ranges. We numerically demonstrate that the topological structure of the periodic orbits in the frequency – energy plane of the underlying hamiltonian system greatly influences the strength of targeted energy transfer in the damped system, and governs to a great extent the overall transient damped dynamics. This work may be regarded as a contribution towards proving the efficacy the utilizing essentially nonlinear attachments as passive broadband boundary controllers. [less ▲]

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See detailMulti-Harmonic Modelling of Motional Magnetic Field Problems using a Hybrid Finite Element--Boundary Element Discretisation
Gyselinck, J.; Geuzaine, Christophe ULg; Dular, Patrick ULg et al

in Journal of Computational & Applied Mathematics (2004), 168

Detailed reference viewed: 12 (1 ULg)
Peer Reviewed
See detailMulti-Harmonic Modelling of Motional Magnetic Field Problems using a Hybrid Finite Element--Boundary Element Discretisation
Gyselinck, J.; Geuzaine, Christophe ULg; Dular, Patrick ULg et al

in 2nd international conference on advanced computational methods in engineering, ACOMEN 2002 (2002)

Detailed reference viewed: 15 (3 ULg)
Peer Reviewed
See detailMulti-level dynamic state estimation for electric power systems
Rousseaux, Patricia ULg; Van Cutsem, Thierry ULg; Ribbens-Pavella, Mania

in Proceedings of the 8th Power System Computation Conference (PSCC) (1984)

Detailed reference viewed: 26 (0 ULg)
See detailMulti-level Politics in a transnational social space: the case of Brussels
Martiniello, Marco ULg

Scientific conference (1999, March 11)

Detailed reference viewed: 10 (0 ULg)
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See detailThe multi-ligand somatostatin analogue SOM230 inhibits ACTH secretion by cultured human corticotroph adenomas via somatostatin receptor type 5.
Hofland, Leo J.; van der Hoek, Joost; Feelders, Richard et al

in European Journal of Endocrinology (2005), 152(4), 645-654

Objective: Currently, there is no effective medical treatment for patients with pituitary-dependent Cushing’s disease. A novel somatostatin (SS) analogue, named SOM230, with high binding affinity to SS ... [more ▼]

Objective: Currently, there is no effective medical treatment for patients with pituitary-dependent Cushing’s disease. A novel somatostatin (SS) analogue, named SOM230, with high binding affinity to SS receptor subtypes sst1, sst2, sst3 and sst5 was recently introduced. We compared the in vitro effects of the sst2-preferring SS analogue octreotide (OCT) and the multi-ligand SOM230 on ACTH release by human and mouse corticotroph tumour cells. Methods: By quantitative RT-PCR the sst subtype expression level was determined in human corticotroph adenomas. In vitro, the inhibitory effect of OCT and SOM230 on ACTH release by dispersed human corticotroph adenoma cells and mouse AtT20 corticotroph adenoma cells was determined. In addition, the influence of dexamethasone on the responsiveness to OCT and SOM230 was studied. Results: Corticotroph adenomas expressed predominantly sst5 mRNA (six out of six adenomas), whereas sst2 mRNA expression was detected at significantly lower levels. In a 72 h incubation with 10 nmol/l SOM230, ACTH release was inhibited in three out of five cultures (range –30 to –40%). Ten nmol/l OCT slightly inhibited ACTH release in only one of five cultures (– 28%). In AtT20 cells, expressing sst2, sst3 and sst5, SOM230 inhibited ACTH secretion with high potency (IC50 0.2 nmol/l). Dexamethasone (10 nmol/l) pre-treatment did not influence the sensitivity of the cells to the inhibitory effect of SOM230, suggesting that sst5 is relatively resistant to negative control by glucocorticoids. Conclusions: The selective expression of sst5 receptors in corticotroph adenomas and the preferential inhibition of ACTH release by human corticotroph adenoma cells by SOM230 in vitro, suggest that SOM230 may have potential in the treatment of patients with pituitary-dependent Cushing’s disease. [less ▲]

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See detailMulti-method monitoring of odor emissions in agricultural biogas facilities.
Nicolas, Jacques ULg; Adam, Gilles ULg; Ubeda, Yolanda et al

in Proceedings of the 5th IWA conference on odours and air emissions, San Francisco, USA, March, 4-7, 2013 (2013, March)

The production of farm-based biogas and electricity is an area of alternative-energy interest to many livestock producers. However, it is still insignificant in comparison to the maximum potential of ... [more ▼]

The production of farm-based biogas and electricity is an area of alternative-energy interest to many livestock producers. However, it is still insignificant in comparison to the maximum potential of farms all over the world. Market penetration should involve better confidence in the technique and better understanding of its possible assets and limits. For instance, is the environmental impact of biomethanation positive or negative? What are the possible ways to avoid or to control process imbalances? In the context of a European project, the research group attempted to tackle those questions under the angle of gas emission and more particularly of odor annoyance. A multi-method approach was applied to monitor biogas and odor emissions, both at the laboratory level on pilot plants and at real scale in 4 agricultural biogas facilities, in Belgium, Luxembourg, France and Germany. Results show that digested material is generally less odorant than crude manure or slurry, while preserving all the amendment and fertilizing qualities of the original material. Possible annoyance of agricultural biogas facilities in the surroundings remains limited and can be solved through simple techniques. [less ▲]

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See detailMulti-Months Cycles Observed in Climatic Data
Nicolay, Samuel ULg; Mabille, Georges ULg; Fettweis, Xavier ULg et al

in Simard, Suzanne (Ed.) Climate Change and Variability (2010)

Climatic variations happen at all time scales and since the origins of these variations are usually of very complex nature, climatic signals are indeed chaotic data. The identification of the cycles ... [more ▼]

Climatic variations happen at all time scales and since the origins of these variations are usually of very complex nature, climatic signals are indeed chaotic data. The identification of the cycles induced by the natural climatic variability is therefore a knotty problem, yet the knowing of these cycles is crucial to better understand and explain the climate (with interests for weather forecasting and climate change projections). Due to the non-stationary nature of the climatic time series, the simplest Fourier-based methods are inefficient for such applications (see e.g. Titchmarsh (1948)). This maybe explains why so few systematic spectral studies have been performed on the numerous datasets allowing to describe some aspects of the climate variability (e.g. climatic indices, temperature data). However, some recent studies (e.g. Matyasovszky (2009); Paluš & Novotná (2006)) show the existence of multi-year cycles in some specific climatic data. This shows that the emergence of new tools issued from signal analysis allows to extract sharper information from time series. Here, we use a wavelet-based methodology to detect cycles in air-surface temperatures obtained from worldwide weather stations, NCEP/NCAR reanalysis data, climatic indices and some paleoclimatic data. This technique reveals the existence of universal rhythms associated with the periods of 30 and 43 months. However, these cycles do not affect the temperature of the globe uniformly. The regions under the influence of the AO/NAO indices are influenced by a 30 months period cycle, while the areas related to the ENSO index are affected by a 43 months period cycle; as expected, the corresponding indices display the same cycle. We next show that the observed periods are statistically relevant. Finally, we consider some mechanisms that could induce such cycles. This chapter is based on the results obtained in Mabille & Nicolay (2009); Nicolay et al. (2009; 2010). [less ▲]

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See detailMulti-national, Multi-cultural and Multi-levelled Brussels : National and Ethnic Politics in the « Capital of Europe »
Martiniello, Marco ULg; Favell, Adrian

in Fonseca, Maria-Lucinda (Ed.) Cities in Movement : Migrants and Urban Change (2008)

Detailed reference viewed: 46 (2 ULg)
See detailMulti-national, multi-cultural and multi-levelled Brussels: national and ethnic politics in the "Capital of Europe"
Martiniello, Marco ULg; Favell, A.

Book published by The Transnational Communities Programme, University of Oxford (1999)

Detailed reference viewed: 15 (2 ULg)
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See detailMulti-Objective Optimization of a Fan Blade by Coupling a Genetic Algorithm and a Parametric Flow Solver
Kelner, Vincent ULg; Grondin, Gilles; Léonard, Olivier ULg et al

in Proceedings of EUROGEN'05 (2005, September)

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See detailMulti-party Arbitration under the UNCITRAL Rules
Kohl, Benoît ULg

Conference given outside the academic context (2008)

Detailed reference viewed: 46 (1 ULg)
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See detailMulti-period load assignment problem with stochastic load availability
Crama, Yves ULg; Pironet, Thierry ULg

E-print/Working paper (2013)

In this research, we want to investigate optimization techniques for a generic load assignment problem including a limited fleet of vehicles within a full-truck-load (FTL) multi-period setting including ... [more ▼]

In this research, we want to investigate optimization techniques for a generic load assignment problem including a limited fleet of vehicles within a full-truck-load (FTL) multi-period setting including forecasts on load availability. Several policies are generated from simple heuristics through state of the art approaches such as consensus and restricted expectation algorithms up to the optimization of a subtree of scenarios. Moreover, myopic and a-posteriori deterministic optimizations (including no or fully revealed information) set bounds for policies performance comparisons. Tests are performed for different graphs sizes and sparsity, several distribution laws and number of loads. Performances are compared statistically over paired samples. The robustness of performing policies against a false valuation of the probability distribution is also analyzed. [less ▲]

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See detailMulti-period vehicle loading with stochastic release dates
Arda, Yasemin ULg; Crama, Yves ULg; Kronus, David ULg et al

in EURO Journal on Transportation and Logistics (in press)

This paper investigates a multi-period vehicle loading problem with stochastic information regarding the release dates of items to be transported. The deterministic version of the problem can be ... [more ▼]

This paper investigates a multi-period vehicle loading problem with stochastic information regarding the release dates of items to be transported. The deterministic version of the problem can be formulated as a large-scale set covering problem. Several heuristic algorithms are proposed to generate decision policies for the stochastic optimization model over a long rolling horizon. The resulting policies have been extensively tested on instances which display the main characteristics of the industrial case-study that motivated the research. The tests demonstrate the benefits of the multi-period stochastic model over simple myopic strategies. A simple and efficient heuristic is shown to deliver good policies and to be robust against errors in the estimation of the probability distribution of the release dates. [less ▲]

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See detailMulti-physical processes in geomechanics – an introduction to constitutive modelling and coupling aspects
Charlier, Robert ULg; Dizier, Arnaud ULg; Laloui, Lyesse et al

in European Journal of Environmental and Civil Engineering [=EJECE] (2009), 7-8

This paper is the basis for a course dedicated to the geomechanics modelling, taking into account multiphysics couplings. A number of different coupling are discussed, with respectively the fluid flow ... [more ▼]

This paper is the basis for a course dedicated to the geomechanics modelling, taking into account multiphysics couplings. A number of different coupling are discussed, with respectively the fluid flow (saturated and unsaturated) and the thermal transfers in deformable porous media. Eventually some aspects on the numerical modelling with the finite element method are discussed. [less ▲]

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See detailMulti-physics modeling
Terrapon, Vincent ULg

Scientific conference (2010, February)

Detailed reference viewed: 11 (3 ULg)