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See detailINTEGRAL detection of hard X-rays from NGC 6334: nonthermal emission from colliding winds or an AGN?
Bykov, A. M.; Krassilchtchikov, A. M.; Uvarov, Y. A. et al

in Astronomy and Astrophysics (2006), 449(3), 917-923

Aims. We report the detection of hard X-ray emission from the field of the star-forming region NGC 6334 with the International Gamma-Ray Astrophysics Laboratory INTEGRAL. Methods. The JEM-X monitor and ... [more ▼]

Aims. We report the detection of hard X-ray emission from the field of the star-forming region NGC 6334 with the International Gamma-Ray Astrophysics Laboratory INTEGRAL. Methods. The JEM-X monitor and ISGRI imager aboard INTEGRAL and Chandra ACIS imager were used to construct 3-80 keV images and spectra of NGC 6334. Results. The 3-10 keV and 10-35 keV images made with JEM-X show a complex structure of extended emission from NGC 6334. The ISGRI source detected in the energy ranges 20-40 keV, 40-80 keV, and 20-60 keV coincides with the NGC 6334 ridge. The 20-60 keV flux from the source is (1.8 +/- 0.37) x 10(-11) erg cm(-2) s(-1). Spectral analysis of the source revealed a hard power-law component with a photon index about 1. The observed X-ray fluxes are in agreement with extrapolations of X-ray imaging observations of NGC 6334 by Chandra ACIS and ASCAGIS. Conclusions. The X-ray data are consistent with two very different physical models. A probable scenario is emission from a heavily absorbed, compact and hard Chandra source that is associated with the AGN candidate radio source NGC 6334B. Another possible model is the extended Chandra source of nonthermal emission from NGC 6334 that can also account for the hard X-ray emission observed by INTEGRAL. The origin of the emission in this scenario is due to electron acceleration in energetic outflows from massive early type stars. The possibility of emission from a young supernova remnant, as suggested by earlier infrared observations of NGC 6334, is constrained by the non-detection of Ti-44 lines. [less ▲]

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See detailIntegral equation methods for the Helmholtz problem with a random impedance condition
Gaignaire, R.; Geuzaine, Christophe ULg

in Proceedings of the 9th International Conference on Mathematical and Numerical Aspects of Waves, Waves 2009 (2009)

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See detailIntegral Field Spectroscopy of Selected Extragalactic Objects with FUEGOS
Surdej, Jean ULg; Vanderriest, C.; Angonin-Willaime, M.-C. et al

in Walsh, J.; Danziger, J. (Eds.) Science with the VLT (1995)

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See detailThe integral membrane FtsW protein and peptidoglycan synthase PBP3 form a subcomplex in Escherichia coli
Fraipont, Claudine ULg; Alexeeva, Svetlana; Wolf, Benoît et al

in Microbiology (2011), 157

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See detailINTEGRAL-ISGRI observations of the cygnus OB2 region - Searching for hard X-ray point sources in a region containing several non-thermal emitting massive stars
De Becker, Michaël ULg; Rauw, Grégor ULg; Pittard, J. M. et al

in Astronomy and Astrophysics (2007), 472(3), 905-910

Aims. We analyze INTEGRAL-ISGRI data in order to probe the hard X-ray emission ( above 20 keV) from point sources in the CygOB2 region and to investigate the putative non-thermal high-energy emission from ... [more ▼]

Aims. We analyze INTEGRAL-ISGRI data in order to probe the hard X-ray emission ( above 20 keV) from point sources in the CygOB2 region and to investigate the putative non-thermal high-energy emission from early-type stars (Wolf-Rayet and O-type stars). Among the targets located in the field of view, we focus on the still unidentified EGRET source 3EG2033+4118 that may be related to massive stars known to produce non-thermal emission in the radio domain, and on the wide colliding-wind binary WR 140. Methods. Using a large set of data obtained with the IBIS-ISGRI imager onboard INTEGRAL, we run the OSA software package in order to find point sources in the fully coded field of view of the instrument. Results. Our data do not allow the detection of a lower-energy counterpart of 3EGJ2033+4118 nor of any other new point sources in the field of view, and we derive upper limits on the high-energy flux for a few targets: 3EGJ2033+4118, TeVJ2032+4130, WR 140, WR 146 and WR 147. The results are discussed in the context of the multiwavelength investigation of these objects. Conclusions. The upper limits derived are valuable constraints for models aimed at understanding the acceleration of particles in non-thermal emitting massive stars, and of the still unidentified very-high gamma-ray source TeVJ2032+4130. [less ▲]

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See detailIntegrated adsorbent and process characterization. Application to air separation PSA processes
Khoder Agha, R.; De Weireld, Guy; Frère, Marc et al

Conference (2005)

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See detailIntegrated approach for assessing climate change impacts on a regional chalky aquifer in Belgium
Goderniaux, Pascal ULg; Brouyère, Serge ULg; Dassargues, Alain ULg

in Changes in water resource systems: methodologies to maintain water security and ensure integrated management (2007)

An integrated hydrological model was developed in order to study the potential effects of climate change on groundwater resources. This model considers most hydrological processes in a physically ... [more ▼]

An integrated hydrological model was developed in order to study the potential effects of climate change on groundwater resources. This model considers most hydrological processes in a physically consistent way. More particularly, groundwater flows are modelled using a spatially distributed finite element approach. The river-aquifer interactions are explicitly taken into account in the model, as well as the spatial heterogeneity of the chalk geology characteristics. After a detailed calibration on the last 30 years and validation on recent periods, quantitative interpretations can be drawn from the ground¬water model results. Considering IPCC climate change scenarios, it appears that, on a multi-annual basis, most tested scenarios predict a decreasing trend in groundwater levels in the Geer Basin. These first results indicate that groundwater deficits may be expected in the future in Belgium. Moreover, at this stage of the study, this trend is computed for a very “optimistic” scenario, neglecting all other pressure changes on the groundwater resources (i.e. no change in land use and in pumping conditions). [less ▲]

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See detailAn Integrated Approach in Dam Breaching Modelling, Provided by WOLF Software
Dewals, Benjamin ULg

Conference (2002, April 19)

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See detailAn Integrated Assessment Frame as Science Policy Interface for Decisions on (Environment-Related) Risks - SCOPE - Report Phase 1
TORFS, RUDI; Zwetkoff, Catherine ULg; Fallon, Catherine ULg

Report (2009)

Classical risk assessment paradigms no longer suffice to deal with complex, uncertain and ambiguous risks. Therefore, new approaches to prevent, control, communicate, and deal with the causes of these ... [more ▼]

Classical risk assessment paradigms no longer suffice to deal with complex, uncertain and ambiguous risks. Therefore, new approaches to prevent, control, communicate, and deal with the causes of these risks and with public anxieties about risks are necessary. In phase 1 we analyzed the available concepts to integrate risk and economical assessment with social aspects in one framework, and discussed the relevant criteria that need to be considered in order to develop a final risk assessment framework. Furthermore, still in phase 1, empirical work was performed in the form of case studies to analyze and define a framework, or to select criteria. We are in the process of reviewing, selecting, and testing tools and instruments that can be used in this appraisal framework, to go from concepts to practice. To grasp the full complexity of controversial, uncertain and immature risks, to cope with different values and views, and to develop a good communication we consider the appraisal framework as a procedural decision making process. It requires a more participative approach as the legal rational approach does not deliver adequate public management tools for handling these issues. We propose a sequential model, going through a series of steps, that can be used both in cases of strategic planning and management, and in the management of local projects usually related to siting conflicts. In each phase of the model integrated assessment tools and methods can be applied up to the point where consensus or a clear representation of different values and views (ideal in very uncertain and ambiguous problems), or an optimal balance between different criteria (in more simple cases) is achieved. All together our Appraisal Framework [is shaped] as a process, structuring and supporting the decision-making process. • To promote and organize a mutual learning of all actors entering into the policy cycle spiralling up through the different phases. • In the context of local siting conflicts, local contamination issues and urban planning topics (all with very close relationships with individuals), including regional, global E&H issues (food, climate, air, transport…) It’s a policy cycle, focused around a certain problem, organised to formulate and evaluate policy options, with stakeholders involved at different phases and steps of the process. Here the AF is structured as a learning network composed of all the players entering into the decision-making process at different stages. The quality of the decision making process can be appreciated either on the basis of its outcomes or on the process itself. Our framing falls under the latter. It also rests on the procedural equity feeling and its impact on the acceptability of the effects of the decision (Joss S. and Brownlea A., 1999). Such an approach opens the way to a greater legitimacy of decisions whose substantive effects or outcomes are essentially dubious – a fortiori in the context of the precaution. It encourages a reflection on the manner of combining the opening of the decision-making process through participative methods with others meta-tools such as strategic management, integrated and comparative approach of the risk, or the evaluative method. These meta-tools structure the participative step, giving it objectives, precise questions and ad hoc means. It contributes to the technical quality of the decision and to its social acceptability, particularly when it is the product of a decision-making process which the actors consider precautionary and adapted to the context of great scientific uncertainty. [less ▲]

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See detailIntegrated assessment of flood protection measures in the context of climate change: hydraulic modelling and economic approach
Dewals, Benjamin ULg; Giron, Eve; Ernst, Julien ULg et al

in Aravossis, K.; Brebbia, C. A.; Gomez, Nieves (Eds.) Environmental Economics (2008)

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See detailAn integrated autonomous protection system against voltage instability based on Load Tap Changers
Vournas, Costas; Lambrou, C.; Glavic, M. et al

in Proceedings of the 2010 IREP Symposium- Bulk Power System Dynamics and Control – VIII (2010, August)

In this paper we propose a local, completely autonomous protection system against voltage instability that can be readily integrated in the controller of each bulk power delivery LTC transformer. The ... [more ▼]

In this paper we propose a local, completely autonomous protection system against voltage instability that can be readily integrated in the controller of each bulk power delivery LTC transformer. The protection system will identify an imminent voltage instability and will subsequently apply the necessary corrective measures to restore stable operation by properly adjusting the distribution voltage setpoint of the LTC. Application of this system on a 52-bus test system showed excellent performance for two unstable cases. For reasons of comparison, the indirect load curtailment proposed in a severe instability case is compared with direct load shedding schemes based on the local detection of instability, as well as on a global detection of instability assuming wide area measurements. [less ▲]

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See detailIntegrated backscatter for the in vivo quantification of supraphysiological vitamin D(3)-induced cardiovascular calcifications in rats.
Roosens, Bram; Droogmans, Steven; Hostens, Jeroen et al

in Cardiovascular Toxicology (2011), 11(3), 244-52

Cardiovascular calcifications are frequently found in the aging population and are independent predictors of future cardiovascular events. Integrated backscatter (IB) of ultrasound reflectivity can easily ... [more ▼]

Cardiovascular calcifications are frequently found in the aging population and are independent predictors of future cardiovascular events. Integrated backscatter (IB) of ultrasound reflectivity can easily quantify calcifications. For this purpose, 30 male Wistar rats received 25,000 IU/kg/day of vitamin D(3) (group 1, n = 8), 18,800 IU/kg/day (group 2, n = 8), or injections with the vehicle only (group 3, n = 14), for 10 weeks. Echocardiographic calibrated IB (cIB) was measured and calculated at baseline and after 10 weeks, followed by ex vivo micro-CT and histopathology of the aortic valve, ascending aorta, and myocardium. After 10 weeks, the mean cIB value of the aortic valve was significantly higher for vitamin D(3)-dosed animals compared to controls. The mean cIB value of the ascending aorta and the myocardium was also significantly higher in group 1 compared to group 3. In vivo IB results were confirmed by ex vivo micro-CT and histopathology. In conclusion, IB is a non-ionizing, feasible, and reproducible tool to quantify cardiovascular calcifications in an in vivo rat model. The integration of IB in the standard echocardiographic examination for the quantification of cardiovascular calcifications could be useful for serial evaluation of treatment efficacy and for prognosis assessment. [less ▲]

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See detailIntegrated bio-chemostratigraphical correlations and climatic evolution across the Danian-Selandian boundary at low latitudes
Storme, Jean-Yves ULg; Steurbaut, Etienne; Devleeschouwer, Xavier et al

in Palaeogeography, Palaeoclimatology, Palaeoecology (2014), 414

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See detailIntegrated biological control of crown rot of bananas with Candida oleophila strain O, calcium chloride and modified atmosphere
de Lapeyre de Bellaire, Luc; Lassois, Ludivine ULg; Bastiaanse, Héloïse ULg et al

in Borja; Nogales; Orrantia (Eds.) et al Memories of 18th Reuniao international ACORBAT meeting (2008)

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See detailIntegrated control and structural analysis of DFIG wind turbines using a monolithic approach
Chen, Qiongzhong ULg; D'Ambrosio, Flavio; Defourny, Michel et al

in Proceedings of the European Wind Energy Conference and Exhibition 2012 (EWEA 2012) (2012, April)

Design of wind turbines requires the coupled analysis among the mechanical, control and aerodynamic subsystems. Different from previous research, which either uses a complicated mechanical model with a ... [more ▼]

Design of wind turbines requires the coupled analysis among the mechanical, control and aerodynamic subsystems. Different from previous research, which either uses a complicated mechanical model with a simple control system model, or vice versa, this paper studies the coupling of subsystems’ dynamics using a high-fidelity aeroelastic model of wind turbine and a detailed analytical model of control generating systems. A monolithic time integration approach is applied so that better numerical accuracy and stability are achieved. Control strategies on power optimization are discussed taking into account the influence of structural flexibility. Simulation examples are given on both stable and turbulent wind situation. [less ▲]

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