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See detailImproved Implementation of the Harmonic Balance Method
Vio, Gareth Arthur; Dimitriadis, Grigorios ULg; Cooper, Jonathan Edward

in Proceedings of the 48th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference (2007, April)

Harmonic Balance (HB) methods have been applied to non-linear aeroelastic problems since the 1980s. As the computational power available to researchers has increased, so has the order of calculated HB ... [more ▼]

Harmonic Balance (HB) methods have been applied to non-linear aeroelastic problems since the 1980s. As the computational power available to researchers has increased, so has the order of calculated HB solutions. However, the computational cost of a HB solution increases with the square of the order. Additionally, the traditional Newton-Raphson, Broyden, Toeplitz Jacobian and other techniques used for the solution of the non-linear algebraic problem at the heart of the HB methodology rely on a good initial guess for the unknown coefficients. If there are many such coefficients the probability that a good guess will be available is very low and the HB scheme may well fail. In this paper a search procedure using Genetic Algorithms (GA) is introduced to evaluate the coefficients of a harmonic balance solution. It is shown that the GA can provide high quality initial guesses for the HB coefficients. The method is applied to an aeroelastic galloping-type problem. [less ▲]

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See detailImproved management practices to increase productivity of traditional cereal/pigeonpea intercropping systems in Eastern Africa.
Mergeai, Guy ULg; Silim, S. N.; Baudoin, Jean-Pierre ULg

in Status and potential of pigeonpea in eastern and southern Africa.Proceedings of a regional workshop, Nairobi, Kenya, 12-15 September 2000 (2001)

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See detailImproved mapping of Jupiter’s auroral features to magnetospheric sources
Vogt, Marissa. F.; Kivelson, Margaret. G.; Khurana, Krishan. K. et al

in Journal of Geophysical Research. Space Physics (2011), 116

The magnetospheric mapping of Jupiter's polar auroral emissions is highly uncertain because global Jovian field models are known to be inaccurate beyond ∼30 RJ. Furthermore, the boundary between open and ... [more ▼]

The magnetospheric mapping of Jupiter's polar auroral emissions is highly uncertain because global Jovian field models are known to be inaccurate beyond ∼30 RJ. Furthermore, the boundary between open and closed flux in the ionosphere is not well defined because, unlike the Earth, the main auroral oval emissions at Jupiter are likely associated with the breakdown of plasma corotation and not the open/closed flux boundary in the polar cap. We have mapped contours of constant radial distance from the magnetic equator to the ionosphere in order to understand how auroral features relate to magnetospheric sources. Instead of following model field lines, we map equatorial regions to the ionosphere by requiring that the magnetic flux in some specified region at the equator equals the magnetic flux in the area to which it maps in the ionosphere. Equating the fluxes in this way allows us to link a given position in the magnetosphere to a position in the ionosphere. We find that the polar auroral active region maps to field lines beyond the dayside magnetopause that can be interpreted as Jupiter's polar cusp; the swirl region maps to lobe field lines on the night side and can be interpreted as Jupiter's polar cap; the dark region spans both open and closed field lines and must be explained by multiple processes. Additionally, we conclude that the flux through most of the area inside the main oval matches the magnetic flux contained in the magnetotail lobes and is probably open to the solar wind. [less ▲]

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See detailAn Improved Method of Photometric Mode Identification: Applications to Slowly Pulsating B, beta Cephei, delta Scuti and gamma Doradus Stars
Dupret, Marc-Antoine ULg; Scuflaire, Richard ULg; Noels-Grötsch, Arlette ULg et al

in Astrophysics & Space Science (2003), 284

We present an improved version of the method of photometric mode identification based upon the inclusion of non-adiabatic eigenfunctions determined in the stellar atmosphere, according to the formalism ... [more ▼]

We present an improved version of the method of photometric mode identification based upon the inclusion of non-adiabatic eigenfunctions determined in the stellar atmosphere, according to the formalism recently proposed by Dupret et al. (2002). We apply our method to beta Cephei, Slowly Pulsating B, delta Scuti and gamma Doradus stars. Besides identifying the degree l of the pulsating stars, our method is also a tool for improving the knowledge of stellar interiors and atmospheres, by imposing constraints on the metallicity for beta Cephei and SPBs, the characteristics of the superficial convection zone for delta Scuti and gamma Doradus stars and the limb-darkening law. [less ▲]

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See detailAn Improved Methodology for Filling Missing Values in Spatiotemporal Climate Dataset: Application to Tanganyika Lake Dataset
Sorjamaa, Antti; Lendasse, Amaury; Cornet, Yves ULg et al

in Computational Geosciences (2010), 14(1), 55-64

In this paper, an improved methodology for the determination of missing values in a spatio-temporal database is presented. This methodology performs denoising projection in order to accurately fill the ... [more ▼]

In this paper, an improved methodology for the determination of missing values in a spatio-temporal database is presented. This methodology performs denoising projection in order to accurately fill the missing values in the database. The improved methodology is called EOF Pruning and it is based on an original linear projection method called Empirical Orthogo- nal Functions (EOF). The experiments demonstrate the performance of the improved methodology and present a comparison with the original EOF and with a widely-used Optimal Interpolation method called Objective Analysis. [less ▲]

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See detailImproved modelling of helium and tritium production for spallation targets
Leray, S.; Boudard, A.; Cugnon, Joseph ULg et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2010), 268(6), 581-586

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See detailImproved molecular diagnostics of idiopathic short stature and allied disorders: quantitative polymerase chain reaction-based copy number profiling of SHOX and pseudoautosomal region 1.
D'haene, Barbara; Hellemans, Jan; Craen, Margarita et al

in Journal of Clinical Endocrinology and Metabolism (2010), 95(6), 3010-8

CONTEXT: Short stature has an incidence of three in 100 in children. Reliable molecular genetic testing may be crucial in the context of beneficial disease management. Deletions spanning or surrounding ... [more ▼]

CONTEXT: Short stature has an incidence of three in 100 in children. Reliable molecular genetic testing may be crucial in the context of beneficial disease management. Deletions spanning or surrounding the SHOX gene account for a significant proportion of patients with idiopathic short stature (ISS) and allied disorders, such as Leri-Weill dyschondrosteosis. OBJECTIVE: Several shortcomings of current strategies for copy number profiling of the SHOX region prompted us to develop an improved test for molecular diagnostics of the SHOX region. DESIGN AND RESULTS: We introduced a quantitative PCR (qPCR)-based copy number profiling test, consisting of 11 amplicons targeting clinically relevant regions, i.e. the SHOX gene and regulatory regions. To ensure an optimal sensitivity and specificity, this test was validated in 32 controls and 18 probands with previously identified copy number changes. In addition, 152 probands with SHOX-associated phenotypes were screened, revealing 10 novel copy number changes. CONCLUSION: This highly validated qPCR test supersedes other approaches for copy number screening of the SHOX region in terms of reliability, accuracy, and cost efficiency. In addition, another strong point is the fact that it can be easily implemented in any standard equipped molecular laboratory. Our qPCR-based test is highly recommended for molecular diagnostics of idiopathic short stature and allied disorders. [less ▲]

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See detailAn Improved Molecular Histology Method for Ion Suppression Monitoring and Quantification of Phosphatidyl Cholines During MALDI MSI Lipidomics Analyses.
Jadoul, Laure ULg; Smargiasso, Nicolas ULg; Pamelard, Fabien et al

in OMICS : A Journal of Integrative Biology (2016), 20(2), 110-21

Tissue lipidomics is one of the latest omics approaches for biomarker discovery in pharmacology, pathology, and the life sciences at large. In this context, matrix-assisted laser desorption/ionization ... [more ▼]

Tissue lipidomics is one of the latest omics approaches for biomarker discovery in pharmacology, pathology, and the life sciences at large. In this context, matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) is the most versatile tool to map compounds within tissue sections. However, ion suppression events occurring during MALDI MSI analyses make it impossible to use this method for quantitative investigations without additional validation steps. This is especially true for lipidomics, since different lipid classes are responsible for important ion suppression events. We propose here an improved lipidomics method to assess local ion suppression of phospatidylcholines in tissues. Serial tissue sections were spiked with different amounts of PC(16:0 d31/18:1) using a nebulization device. Settings for standard nebulization were strictly controlled for a detection similar to when using spiked tissue homogenates. The sections were simultaneously analyzed by MALDI MSI using a Fourier transform ion cyclotron resonance analyzer. Such a spray-based approach allows taking into account the biochemical heterogeneity of the tissue for the detection of PC(16:0 d31/18:1). Thus, here we present the perspective to use this method for quantification purposes. The linear regression lines are considered as calibration curves and we calculate PC(16:0/18:1) quantification values for different ROIs. Although those values need to be validated by a using a different independent approach, the workflow offers an insight into new quantitative mass spectrometry imaging (q-MSI) methods. This approach of ion suppression monitoring of phosphocholines in tissues may be highly interesting for a large range of applications in MALDI MSI, particularly for pathology using translational science workflows. [less ▲]

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See detailImproved one-dimensional numerical simulation of transient mixed flow in water pipes network
Kerger, François ULg; Archambeau, Pierre ULg; Erpicum, Sébastien ULg et al

in Proceedings of the 2nd ENVITAM PhD Day (2008, January 29)

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See detailAN IMPROVED ONE-POINT INTEGRATION METHOD FOR LARGE-STRAIN ELASTOPLASTIC ANALYSIS
Stainier, Laurent ULg; Ponthot, Jean-Philippe ULg

in Computer Methods in Applied Mechanics & Engineering (1994), 118(1-2), 163-177

In this paper, we present a new one-point integration method generalizing Flanagan and Belytschko's method (Internat. J. Numer. Methods Engrg. 17 (1981) 679-706) and a modification of Belytschko and ... [more ▼]

In this paper, we present a new one-point integration method generalizing Flanagan and Belytschko's method (Internat. J. Numer. Methods Engrg. 17 (1981) 679-706) and a modification of Belytschko and Bindeman's method (Comput. Methods Appl. Mech. Engrg. 88 (1991) 311-340), both in the frame of large deformation elastoplastic analysis. These stabilization methods are combined with the radial return method used to integrate the constitutive law. Plane strain problems are first considered, and the method is then generalized to axisymmetrical situations. The explicit time integration scheme with its critical timestep is also considered. A few examples are presented that show the great time savings that can be obtained with reduced integration without any loss of accuracy, and even with a gain in the solution quality, since the underintegrated elements prove to be 'flexurally superconvergent'. [less ▲]

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See detailImproved operational model for real-time reconstruction of the electron density profile at a single ionosonde location
Stankov, Stanimir; Warnant, René ULg; Jodogne, Jean-Claude

in Proceedings of the COST271 2002 workshop (2002, October)

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See detailImproved Outcome Prediction Based on Csf Extrapolated Creatine Kinase Bb Isoenzyme Activity and Other Risk Factors in Severe Head Injury
Hans, Pol ULg; Albert, Adelin ULg; FRANSSEN, Colette ULg et al

in Journal of Neurosurgery (1989), 71(1), 54-8

The present study of 43 patients with severe head injury shows that outcome prediction can be markedly improved by combining an appropriate marker of the degree of initial brain damage and other risk ... [more ▼]

The present study of 43 patients with severe head injury shows that outcome prediction can be markedly improved by combining an appropriate marker of the degree of initial brain damage and other risk factors. The patients were classified into three groups according to their actual outcome after 6 months: death (22 patients); persistent vegetative state or severe disability (eight patients); and moderate disability or good recovery (13 patients). By applying stepwise logistic discriminant analysis to the patients' data, five significant risk factors were selected: degree of neurological damage assessed by cerebrospinal fluid (CSF) extrapolated creatine kinase BB isoenzyme activity, Glasgow-Liege Coma Scale score, age, incidence of thoracic injury, and intracranial pressure (ICP). Extrapolated creatine kinase BB activity had the highest prognostic ability (67%). Uncontrollable elevated ICP proved to be systematically associated with death, whereas its absence was not necessarily indicative of a favorable outcome. The combination of the five variables yielded a total prognostic efficiency of 91%. The percentages of correctly predicted patients for the three outcome groups were, respectively, 100%, 50%, and 100%. Thus, half of the persistently vegetative and severely disabled patients were identified by the selected factors. [less ▲]

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See detailImproved pancreatic K-ATP channel openers belonging to the pyridothiadiazine chemical class
Pirotte, Bernard ULg; De Tullio, Pascal ULg; Lebrun, P. et al

in Journal de Pharmacie de Belgique (1993), 48

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See detailImproved parallelism and scheduling in multi-core software routers
Egi, Norbert; Iannaccone, Gianluca; Manesh, Maziar et al

in Journal of Supercomputing (2011)

Recent technological advances in commodity server architectures, with multiple multi-core CPUs, integrated memory controllers, high-speed interconnects, and enhanced network interface cards, provide ... [more ▼]

Recent technological advances in commodity server architectures, with multiple multi-core CPUs, integrated memory controllers, high-speed interconnects, and enhanced network interface cards, provide substantial computational capacity, and thus an attractive platform for packet forwarding. However, to exploit this available capacity, we need a suitable software platform that allows effective parallel packet processing and resource management. In this paper, we at first introduce an improved forwarding architecture for software routers that enhances parallelism by exploiting hardware classification and multi-queue support, already available in recent commodity network interface cards. After evaluating the original scheduling algorithm of the widely-used Click modular router, we propose solutions for extending this scheduler for improved fairness, throughput, and more precise resource management. To illustrate the potential benefits of our proposal, we implement and evaluate a few key elements of our overall design. Finally, we discuss how our improved forwarding architecture and resource management might be applied in virtualized software routers. [less ▲]

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See detailImproved parameters for the transiting hot Jupiters WASP-4b and WASP-5b
Gillon, Michaël ULg; Smalley, B.; Hebb, L. et al

in Astronomy and Astrophysics (2009), 496

The gaseous giant planets WASP-4b and WASP-5b are transiting 12-magnitude solar-type stars in the Southern hemisphere. The aim of the present work is to refine the parameters of these systems using high ... [more ▼]

The gaseous giant planets WASP-4b and WASP-5b are transiting 12-magnitude solar-type stars in the Southern hemisphere. The aim of the present work is to refine the parameters of these systems using high cadence VLT/FORS2 z-band transit photometry and high-resolution VLT/UVES spectroscopy. For WASP-4, the new estimates for the planet radius and mass from a combined analysis of our VLT data with previously published transit photometry and radial velocities are R[SUB]p[/SUB] = 1.30[SUP]+0.05[/SUP][SUB]-0.04[/SUB] R[SUB]J[/SUB] and M[SUB]p[/SUB] = 1.21[SUP]+0.13[/SUP][SUB]-0.08[/SUB] M_J, resulting in a density rho[SUB]p[/SUB] = 0.55[SUP]+0.04[/SUP][SUB]-0.02[/SUB] rho_J. The radius and mass for the host star are R_* = 0.87[SUP]+0.04[/SUP][SUB]-0.03[/SUB] R_o and M_* = 0.85[SUP]+0.11[/SUP][SUB]-0.07[/SUB] M_o. Our ground-based photometry reaches 550 ppm at time sampling of ~50 s. Nevertheless, we also report the presence of an instrumental effect on the VLT that degraded our photometry for the WASP-5 observations. This effect could be a major problem for similar programs. Our new estimates for the parameters of the WASP-5 system are R[SUB]p[/SUB] = 1.09 ± 0.07 R_J, M[SUB]p[/SUB] = 1.58[SUP]+0.13[/SUP][SUB]-0.10[/SUB] M_J, rho[SUB]p[/SUB] = 1.23 [SUP]+0.26[/SUP][SUB]-0.16[/SUB] rho_J, R_* = 1.03[SUP]+0.06[/SUP][SUB]-0.07[/SUB] R_o, and M_* = 0.96[SUP]+0.13[/SUP][SUB]-0.09[/SUB] M_o. The measured size of WASP-5b agrees well with the basic models of irradiated planets, while WASP-4b is clearly an ``anomalously'' large planet. Based on data collected with the FORS2 imager at the VLT-UT4 telescope and with the UVES spectrograph at the VLT-UT2 telescope (Paranal Observatory, ESO, Chile) in the programme 280.C-5003. [less ▲]

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