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See detailEffective Iterative Solvers for Highly Non-Linear & Large Deformation Pressure Dependent Problems
Boman, Romain ULg; Colantonio, Laurent; Ponthot, Jean-Philippe ULg

in Van Keer, R.; Verhegghe, B.; Hogge, M. (Eds.) et al Proceedings of ACOMEN'98, Advanced Computational Methods in Engineering, part 2: Contributed papers (1998, September)

In this paper, we present a stress update scheme for non-deviatoric elastoviscoplastic models, which can be considered as an extension of the radial return method for classical plasticity. We use the ... [more ▼]

In this paper, we present a stress update scheme for non-deviatoric elastoviscoplastic models, which can be considered as an extension of the radial return method for classical plasticity. We use the unconditionally stable backward Euler scheme to obtain the viscoplastic solution at each increment. To solve the large sparse non symmetric iteration matrix, we use the GMRES method. This fast iterative solver, in conjunction with an appropriate preconditioner, can save a lot a memory and CPU time when 3D problem are considered. A comparison between direct and iterative solvers will be discussed on two applications of cold compaction of powders. [less ▲]

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See detailEffective masses in relativistic approaches to the nucleon-nucleus mean field
Jaminon, Martine ULg; Mahaux, Claude ULg

in Physical Review. C : Nuclear Physics (1989), 40

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See detailEffective particles and classification of periodic orbits of homogeneous granular chains with no precompression
Starosvetsky, Y.; Jayaprakash, K.R.; Vakakis, A.F. et al

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2012), 85

We develop a systematic methodology for classifying the periodic orbits of homogeneous ordered granular chains with no dissipation, under the assumption that all granules oscillate with the same frequency ... [more ▼]

We develop a systematic methodology for classifying the periodic orbits of homogeneous ordered granular chains with no dissipation, under the assumption that all granules oscillate with the same frequency. The analysis is based on the idea of balancing linear momentum for sets of auxiliary models consisting of “effective particles.” The auxiliary models may be defined for any given finite, ordered granular chain composed of n identical granules (beads) that interact with each other through strongly nonlinear Hertzian interaction law. In turn, the auxiliary models may be effectively used for theoretically predicting the total number of periodic orbits and the corresponding amplitude ratios of the granules. Good correspondence between the theoretical models and results of direct numerical simulations is reported. The results presented herein can be used to understand the complex intrinsic dynamics of ordered granular media, and to systematically study the generation of mode localization in these strongly nonlinear systems. The derived analytical models can be utilized to predict the response of the effective particles, and based on that, to predict primary pulse transmission in periodic layered media with granular interfaces. Moreover, our analysis can be extended to the general class of nonlinear chains of particles with smooth interacting potentials and possible separation between particles during the motion. [less ▲]

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See detailEffective porosity values used in calibrated transport simulations in a fissured and slightly karstified chalk aquifer
Hallet, Vincent; Dassargues, Alain ULg

in Herbert, M.; Kovar, K. (Eds.) Groundwater Quality 1998, Tübinger Geowissenschaftliche Arbeiten (TGA) (1998)

In fissured and slighly karstified chalks, the main difficulty for modelling groundwater flow and transport consists in finding a good approximation of the highly heterogeneous reality by a REV concept ... [more ▼]

In fissured and slighly karstified chalks, the main difficulty for modelling groundwater flow and transport consists in finding a good approximation of the highly heterogeneous reality by a REV concept. No major problem is encountered for groundwater flow simulations when the high contrast in hydraulic conductivity can be given to the cells/elements of the model. The Darcy’s law is applied in terms of specific flow rate, through the REV. When considering transport, it is often assumed that the calibrated field of hydraulic conductivity should be kept unchanged. Consequently, ‘physically non acceptable’ values of the effective porosity are often needed to obtain a match between modelled and measured breakthrough curves. The model becomes, to some extent, a black-box model. [less ▲]

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See detailEffective Production of the Biodiesel Additive STBE by a Continuous Flow Process
Monbaliu, Jean-Christophe ULg; Winter, Marc; Chevalier, Bérengère et al

in Bioresource Technology (2011), 102

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See detailEffective resolution of racemic pirlindole at the preparative scale
De Tullio, Pascal ULg; Ceccato, A.; Liégeois, Jean-François ULg et al

in Chirality (1999), 11

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See detailEffective spin model for interband transport in a Wannier-Stark lattice system
Plötz, Patrick; Schlagheck, Peter ULg; Wimberger, Sandro

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (2011), 63

We show that the interband dynamics in a tilted two-band Bose-Hubbard model can be reduced to an analytically accessible spin model in the case of resonant interband oscillations. This allows us to ... [more ▼]

We show that the interband dynamics in a tilted two-band Bose-Hubbard model can be reduced to an analytically accessible spin model in the case of resonant interband oscillations. This allows us to predict the revival time of these oscillations which decay and revive due to inter-particle interactions. The presented mapping onto the spin model and the so achieved reduction of complexity has interesting perspectives for future studies of many-body systems. [less ▲]

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See detailEffective stress method to be used in beam finite elements to take local instabilities into account
Franssen, Jean-Marc ULg; Cowez, Baptiste; Gernay, Thomas ULg

in Proceedings of the 11th IAFSS Symposium (2014, February)

In the fire situation, Bernoulli beam finite elements are the workhorse used in numerical calculation model for simulating the behaviour of the structure. Such finite elements treat all sections as class ... [more ▼]

In the fire situation, Bernoulli beam finite elements are the workhorse used in numerical calculation model for simulating the behaviour of the structure. Such finite elements treat all sections as class 1 (stocky) sections whatever the slenderness of the plates that make the section, allowing the development of a full plastic stress distribution in the section which leads to complete plastic redistribution along the members in the structure. This type of element is thus not adapted for modeling structures that contain slender sections of class 2, 3 or 4. This document presents a new approach to take into account local instabilities in slender sections using beam finite elements. The new approach is based on an effective constitutive law of steel. The effective law is not symmetrical with respect to tension and compression because, in tension, the stress-strain relationship is not modified whereas, in compression, the stress-strain relationship is modified. [less ▲]

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See detailEffective temperature of ions in traveling wave ion mobility spectrometry
Morsa, Denis ULg; Gabelica, Valérie ULg; De Pauw, Edwin ULg

in Analytical Chemistry (2011), 83(14), 5775-5782

Traveling wave ion mobility spectrometers (TW IMS) operate at significantly higher fields than drift tube ion mobility spectrometers. Here we measured the fragmentation of the fragile p ... [more ▼]

Traveling wave ion mobility spectrometers (TW IMS) operate at significantly higher fields than drift tube ion mobility spectrometers. Here we measured the fragmentation of the fragile p-methoxybenzylpyridinium ion inside the TW ion mobility cell of the first-generation SYNAPT HDMS spectrometer. The ion’s vibrational internal energy was quantified by a vibrational effective temperature Teff,vib, which is the mean temperature of the ions inside the cell that would result in the same fragmentation yield as observed experimentally. Significant fragmentation of the probe ion inside the TW IMS cell was detected, indicating that field heating of the ions takes place in TW IMS. For typical small molecule IMS conditions, Teff,vib = 555 ± 2 K. The variations of the effective temperature were studied as a function of the IMS parameters, and we found that Teff,vib decreases when the wave height decreases, when the pressure increases, or when the wave speed increases. The energy transfer efficiency of argon is higher than for He, N2 or CO2. Teff,vib being directly related to the ion speed inside the TW IMS, our results also provide new insight on the ion movement in TW IMS. We also discuss the influence of field heating of ions for calibration and structural studies in TW IMS. [less ▲]

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See detailEffective treatment of Jo-1-associated polymyositis with T-cell-depleted autologous peripheral blood stem cell transplantation.
Baron, Frédéric ULg; Ribbens, Clio ULg; Kaye, O. et al

in British Journal of Haematology (2000), 110(2), 339-342

A patient with Jo-1 antibody-associated polymyositis (Jo-1 PM) had a Karnofsky score of 40% and severe muscle, liver and lung damage that was refractory to standard therapy. The female patient received an ... [more ▼]

A patient with Jo-1 antibody-associated polymyositis (Jo-1 PM) had a Karnofsky score of 40% and severe muscle, liver and lung damage that was refractory to standard therapy. The female patient received an autologous T-cell-depleted haematopoietic stem cell transplant (HSCT) after myeloablative conditioning. The transplant procedure was complicated by severe adult respiratory distress syndrome (ARDS) and adenovirus-associated haemorrhagic cystitis as well as cytomegalovirus (CMV) reactivation. The patient's creatinine phosphokinase (CPK) and alanine transaminase (ALT) values were normal on day 21. The patient's strength has improved remarkably and her dyspnoea is subjectively improved. At 15 months after the transplant, the patient was well with a Karnofsky score of 80% and had been off any therapy, including steroids, for 14 months. [less ▲]

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See detaileffective use of dolomitic material in Mbuji-Mayi region
Matamba Jibikila, Raphaël ULg

Conference (2012, September 12)

En vue d'une utilisation efficace de matériaux dolomitiques du supergroupe de Mbuji-Mayi (RD Congo), une caractérisation méticuleuse de chaque faciès de matériau s'impose. Cela permettrait une bonne ... [more ▼]

En vue d'une utilisation efficace de matériaux dolomitiques du supergroupe de Mbuji-Mayi (RD Congo), une caractérisation méticuleuse de chaque faciès de matériau s'impose. Cela permettrait une bonne gestion de ressources en définissant pour chaque faciès, des applications optimales et durables. [less ▲]

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See detailEffectiveness analysis of resistance and tolerance to infection
Detilleux, Johann ULg

in Genetics, Selection, Evolution (2011)

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See detailEffectiveness and tolerability of pegylated interferon alfa2b in combination with ribavirin for treatment of chronic hepatitis C: the PegIntrust study
Van Vlierberghe, H.; Adler, M.; Bastens, B. et al

in Acta Gastro-Enterologica Belgica (2010), 73

Background and study aims : Large international clinical trials conducted in the past 5 years rapidly improved the treatment of chronic hepatitis C; however, it is unclear whether the advances seen in ... [more ▼]

Background and study aims : Large international clinical trials conducted in the past 5 years rapidly improved the treatment of chronic hepatitis C; however, it is unclear whether the advances seen in clinical trials are being paralleled by similar improvements in routine clinical practice. PegIntrust is a Belgian community based trial evaluating the sustained virological response. Patients and Methods : Observational study of 219 patients receiving pegylated interferon alfa-2b (1.5 μg/kg/wk) and weight-based ribavirin (800-1200 mg/day) for 48 weeks. Primary study end point was sustained virological response (SVR), defined as undetectable HCV RNA 6 months after the completion of treatment. Results : In total, 108 patients (49.3 %) had undetectable HCV RNA at the end of therapy, 91 (41.6%) attaining SVR. Of the 111 patients without an end-of-treatment response, 28 were non-responders, and 21 had virological breakthrough. In total, 134 patients attained early virological response (EVR); 88 (65.7%) of those patients attained SVR. In contrast, 82 (96.5 %) of the 85 patients who did not attain EVR also did not attain SVR. Age, fibrosis score and baseline viral load were identified as important predictors of treatment outcome. The most frequently reported serious adverse events resulting in treatment discontinuation were anemia (n = 10), fatigue/asthenia/malaise (n = 6) and fever (n = 3). Conclusion : Our data indicate that treatment of chronic hepatitis C with PEG-IFN alfa-2b plus weight-based ribavirin results in favourable treatment outcomes in a Belgian cohort of patients treated in community- based clinical practice. [less ▲]

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See detailEffectiveness of a semi-intensive multidisciplinary outpatient rehabilitation program in chronic low back pain
Demoulin, Christophe ULg; Grosdent, Stéphanie ULg; Capron, Lucile et al

in Joint Bone Spine (2010), 77

Objectives: To evaluate the efficacy of a semi-intensive multidisciplinary outpatient program complying with the requirements of the Belgian National Institute for Health and Disability Insurance and ... [more ▼]

Objectives: To evaluate the efficacy of a semi-intensive multidisciplinary outpatient program complying with the requirements of the Belgian National Institute for Health and Disability Insurance and intended for patients with chronic low back pain. Methods: Weincluded 262 patients with nonspecific chronic low back pain, amongwhom136 (73women and 63 men) with a mean pain duration of 11.3 years completed the outpatient program (36 sessions each lasting 2 h). The program consisted of education about back-sparing techniques, interventions by an occupational therapist and psychologist, and physical reconditioning. Three sessions (sessions 1, 18, and 36) were used to evaluate pain intensity, functional impairment, kinesiophobia, cognitive knowledge, knowledge of appropriate spinal movement technique, and physical performance (trunk muscle strength and endurance, mobility of the pelvis and lumbar spine, and aerobic capacity). Results: All study variables were significantly improved at study completion compared to baseline: pain intensity was decreased by 44%, functional impairment by 40%, and kinesiophobia by 11% whereas knowledge was improved by 59%, back-sparing technique by 95%, trunk muscle strength by 40% on average, trunk extensor muscle endurance by 90%, mobility by 8%, and aerobic capacity by 18%. Conclusions: A semi-intensive multidisciplinary outpatient program was beneficial in patients with chronic low back pain. Careful patient selection and increased patient involvement in the program may help to improve adherence. [less ▲]

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See detailEffectiveness of a video training programme used to improve error identification and feedback processes by physical education student teachers
Cloes, Marc ULg; Premuzak, Jean

in International Journal of Physical Education (1995), 32(3), 4-10

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See detailEffectiveness of an acute pain service inception in a general hospital
Bardiau, Françoise ULg; Braeckman, M.M.; SEIDEL, Laurence ULg et al

in Journal of Clinical Anesthesia (1999), 11(7), 583-589

STUDY OBJECTIVES: To assess the effects of an Acute Pain Service (APS) inception on postoperative pain management in a general teaching hospital using pain indicators as performance measures. DESIGN: Open ... [more ▼]

STUDY OBJECTIVES: To assess the effects of an Acute Pain Service (APS) inception on postoperative pain management in a general teaching hospital using pain indicators as performance measures. DESIGN: Open, prospective, nonrandomized, observational study. SETTING: Postanesthesia Care Unit, surgical wards of University Hospital Center of Charleroi. PATIENTS: 1304 patients in the pre-APS inception phase and 671 patients after its implemention who have undergone various types of surgery (orthopedics, gynecology, urology, neurosurgery, stomatology, ear, nose, and throat, ophthalmic, abdominal, vascular-thoracic, plastic, and maxillofacial). INTERVENTIONS: An APS, nurse-based, anesthesiologist-supervised model was devised, based on the concept that postoperative pain relief can be greatly improved by providing in-service training for surgical nursing staff and optimal use of systemic analgesics. MEASUREMENTS AND MAIN RESULTS: Postoperative pain was assessed using a visual analog scale (VAS) every 4 hours for 72 hours in the two phases. Analgesic consumption was registered at the same time. Time-related VAS scores were summarized using several pain indicators. There was an overall improvement in the pain scores after APS inception. The differences were most pronounced, around 50%, in patients undergoing vascular, maxillofacial, gynecologic, and urologic surgeries, and stomatology. Regular administration of paracetamol and nonsteroidal antiinflammatory drugs decreased morphine consumption in the second phase. CONCLUSION: This study validates the benefits of a formal APS, using continuous monitoring of rest pain intensity and analgesic consumption in the postoperative period. Results not only support previous research findings but also offer outcome-based tools to evaluate current practices as compared with desired outcomes. [less ▲]

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