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See detailCalculation Method for Design of Reinforced Concrete Columns under Fire Conditions
Dotreppe, Jean-Claude ULg; Franssen, Jean-Marc ULg; Vanderzeipen, Yves

in ACI Structural Journal (1999), 96(1), 9-18

This paper presents a simple model for the calculation of the fire resistance of reinforced concrete columns. It has been developed on the base of extensive numerical simulations and has been calibrated ... [more ▼]

This paper presents a simple model for the calculation of the fire resistance of reinforced concrete columns. It has been developed on the base of extensive numerical simulations and has been calibrated on the base of a large data base of full scale experimental test results [less ▲]

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See detailCalculation of a Tunnel Cross Section Subjected to Fire
Schneider, U.; Schneider, M.; Franssen, Jean-Marc ULg

in Acta Polytechnica (2009), 49(1/2009), 44-55

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See detailCalculation of autocorrelation functions for electronic spectra
Dehareng, Dominique ULg

in Chemical Physics (1984), 84

The autocorrelation function C(t) associated with the vibrational motion in the A 2Pi u state of N2+ is calculated by three different methods. The classical method is based on classical trajectory ... [more ▼]

The autocorrelation function C(t) associated with the vibrational motion in the A 2Pi u state of N2+ is calculated by three different methods. The classical method is based on classical trajectory calculations and provides good results except for secondary maxima appearing in the experimental autocorrelation function and resulting from interference effects. In the semiclassical method, the wavefunction is expanded in a basis of frozen gaussian functions. The secondary maxima are reproduced and the result is quite satisfactory. The superposition procedure consists in an expansion of the wavefunction in the eigenfunctions of the A state of N2+ and leads to a very simple formula for the autocorrelation function C(t). The secondary maxima are accounted for and the calculated function agrees very well with experimental results. [less ▲]

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See detailCalculation of bovine haemoglobin oxygen saturation by algorithms integrating age, haemoglobin content, blood pH, partial pressures of oxygen and carbon dioxide in the blood, and temperature.
Detry, Benoit; Cambier, Carole ULg; Frans, A. et al

in Veterinary Journal (2003), 165(3), 258-265

In human and veterinary medicine, arterial and venous haemoglobin oxygen saturations are often used to estimate the severity of a disease and to guide therapeutic decisions. In veterinary medicine ... [more ▼]

In human and veterinary medicine, arterial and venous haemoglobin oxygen saturations are often used to estimate the severity of a disease and to guide therapeutic decisions. In veterinary medicine, haemoglobin oxygen saturation (SO(2)) is usually calculated using a blood gas analyser and algorithms developed for humans. It is possible, therefore, that the values obtained in animals may be distorted, particularly in animals with a high haemoglobin oxygen affinity, like young calves. In order to verify this hypothesis, we compared the arterial (SaO(2)) and venous (SvO(2)) haemoglobin oxygen saturations calculated using three different algorithms, and the oxygen exchange fraction (OEF) at the tissue level, which is the degree of haemoglobin desaturation between arterial and venous blood (SaO(2)-SvO(2)), with the values obtained from the whole bovine oxygen equilibrium curve (OEC) determined by a reference method. The blood gas analysers underestimated SvO(2) values; consequently, the OEF was overestimated (by about 10%). Two methods of reducing these errors were assessed. As the haemoglobin oxygen affinity decreases during the first month of life in calves a relationship between PO(2) at 50% haemoglobin saturation (P50) and age was established in order to correct the calculated values of venous and arterial SO(2), taking into account the estimated position of the OEC. This method markedly reduced the error for SvO(2) and OEF. Secondly, the SO(2) was calculated using a mathematical model taking into account the age of the animal and the specific effects of pH, PCO(2), and temperature on the bovine OEC. Using this method, the mean difference between the OEF values calculated using the mathematical model and those calculated by the reference method was close to zero. The errors produced by blood gas analysers can thus be minimised in two ways: firstly, by simply introducing a P50 estimated from the age of the calf into the analyser before the measurement; and secondly, by calculating the SO(2) using a mathematical model applied to the bovine OEC. [less ▲]

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See detailCalculation of Eddy Currents and Associated Losses in Electrical Steel Laminations
Gyselinck, Johan; Vandevelde, Lieven; Melkebeek, Jan et al

in IEEE Transactions on Magnetics (1999), 35(3), 1191-1194

Starting from the well known analytical formula for the eddy current losses in electrical steel laminations, saturation and edge effects are studied by means of 1D and 2D finite element models of a single ... [more ▼]

Starting from the well known analytical formula for the eddy current losses in electrical steel laminations, saturation and edge effects are studied by means of 1D and 2D finite element models of a single lamination. A novel method for directly including the laminated core energy dissipation in a time stepped 2D model of a complete (rotating) machine is proposed. By way of example the method is applied to a tooth model with enforced flux waveforms. [less ▲]

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See detailCalculation of inner shell transitions in Mn+
Quinet, Pascal ULg; Hibbert, A

in Journal of Physics : B Atomic Molecular & Optical Physics (1996), 29

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See detailCalculation of internal forces in axially and rotationally restrained beams under natural fire
Hanus, François ULg

Master of advanced studies dissertation (2008)

When a constituent of a frame is subjected to fire, the thermal dilatation and bowing of this element is limited by the action of the surrounding frame. The reduction of steel mechanical properties and ... [more ▼]

When a constituent of a frame is subjected to fire, the thermal dilatation and bowing of this element is limited by the action of the surrounding frame. The reduction of steel mechanical properties and restrained thermal deformations induce a new distribution of internal forces in the frame. Generally, the stability of structures is calculated by the use of recommended temperature-time curves that do not considered the cooling phase of the fire. After being submitted to high compressive forces and experiencing significant plastic deformations, heated elements become in tension. As it was observed experimentally, the failure of bolts due to an excess of tensile forces may occur during the cooling phase of the fire. That is the reason why a research project on the design of connections subjected to natural fire (COSSFIRE) has been funded by the Research Fund for Coal and Steel (RFCS). The objective of this project is to provide experimental data and to propose guidelines for designing the joints including both the heating and cooling phases. This work describes a part of the contribution of the University of Liège in the project COSSFIRE. It is focused on the determination of the internal forces experienced by axially and rotationally restrained beams submitted to a natural fire. This preliminary step is essential for an optimised design of connections in similar conditions. This work is subdivided three parts. Firstly, some experimental tests have been modelled numerically with the homemade finite element software SAFIR in order to validate it and the models used to analyse this type of problem. Secondly, a set of parametrical analyses have been performed in order to better understand the influence of several factors on the induced internal forces and provide some reference results for the last part of the work. Finally, some simplified methods, based on Wang’s method, have been defined to allow determining the internal forces in a given case without requiring any numerical simulation in finite element packages. [less ▲]

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See detailCalculation of mechanical properties of polymeric foams with closed cell structure produced on the basis of neoprene
Pyka, Grzegorz; Wevers, Martine; Kerckhofs, Greet ULg et al

Conference (2009)

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See detailCalculation of optical absorption spectra of hydrogenated Si clusters: Bethe-Salpeter equation versus time-dependent local-density approximation
Benedict, L. X.; Puzder, A.; Williamson, A. J. et al

in Physical Review. B : Condensed Matter (2003), 68(8), 85310-1-85310-85310-885310-85310-8

We present calculations of the optical absorption spectra of clusters SiH 4, Si 10H 16, Si 17H 36, Si 29H 24, and Si 35H 36, as determined from two different methods: the Bethe-Salpeter equation (BSE ... [more ▼]

We present calculations of the optical absorption spectra of clusters SiH 4, Si 10H 16, Si 17H 36, Si 29H 24, and Si 35H 36, as determined from two different methods: the Bethe-Salpeter equation (BSE) with a model dielectric function, and the time-dependent density-functional theory within the adiabatic local-density approximation (TDLDA). Single-particle states are obtained from local-density approximation (LDA) calculations and, for the BSE calculation, a quasiparticle gap correction is provided by quantum Monte Carlo calculations. We find that the exchange-correlation kernel of the TDLDA has almost no effect on the calculated spectra, while the corresponding attractive part of the electron-hole interaction of the BSE produces enhanced absorptive features at low energies. For the smallest cluster SiH 4, the two methods produce markedly different results, with the TDLDA spectra appearing closer to the experimental result. The gross features of the TDLDA and BSE spectra for larger clusters are however similar, due to the strong repulsive Coulomb kernel present in both treatments [less ▲]

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See detailCalculation of spacer compression for bundle lines under short-circuit.
Lilien, Jean-Louis ULg; papailiou, Konstantin

in IEEE Transactions on Power Delivery (2000), 15(N°2), 839-845

Short-circuit tests results and proposal of a new method to improve Manuzio formula on bundle conductors spacer compression.

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See detailCalculation of temperature in fire-exposed bare steel structures: Comparison between ENV 1993-1-2 and EN 1993-1-2
Franssen, Jean-Marc ULg

in Fire Safety Journal (2006), 41(2), 139-143

A comparison is made between the formula presented in ENV 1993-1-2 and EN 1993-1-2 for calculating temperature in bare steel structures subjected to fire. The ratio between the radiative energy considered ... [more ▼]

A comparison is made between the formula presented in ENV 1993-1-2 and EN 1993-1-2 for calculating temperature in bare steel structures subjected to fire. The ratio between the radiative energy considered in each formula is first calculated for 377 commercially available sections. The evolution of the steel temperature is then calculated in 4 different representative sections. On the basis of these comparisons and taking into account the fact that the load-bearing capacity has to be ensured in steel members, it does not appear that significant modifications in the safety level have been introduced from the ENV to the EN version of Eurocode 3. (C) 2005 Elsevier Ltd. All rights reserved. [less ▲]

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See detailCalculation of the Imaginary Part of the Nucleon-Nucleus Optical-Model Potential
Cugnon, Joseph ULg

in Nuclear Physics A (1973), 208

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See detailCalculation of the random-incidence scattering coefficients of a sine-shaped surface
Embrechts, Jean-Jacques ULg; De Geetere, L.; Vermeir, G. et al

in Acta Acustica United with Acustica (2006), 92(4, JUL-AUG), 593-603

Random-incidence scattering coefficients obtained by measurement in reverberation chambers (ISO 17497-1) for a particular sine-shaped surface are compared with theoretical results. Holford-Urusovskii's ... [more ▼]

Random-incidence scattering coefficients obtained by measurement in reverberation chambers (ISO 17497-1) for a particular sine-shaped surface are compared with theoretical results. Holford-Urusovskii's method and a hybrid plane wave decomposition - FEM method are applied to an infinite sine-shaped surface having the same profile, while the 3D BEM gives numerical results for the finite-size surface. Perfect rigidity (Neumann boundary condition) is assumed in all computations. The validity of the computations is compared and discussed with regard to the approximations involved. Finally, the measured and calculated values of the scattering coefficients are compared. A good correspondence is found, in particular concerning the overall dependence on frequency. Small deviations have however been observed, at low as well as at high frequencies. They will be explained by uncertainties in the measurements and discretisation errors in the calculations. [less ▲]

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See detailCalculation of the scattering coefficient of a sine-shaped surface by solving the Helmholtz integral
Embrechts, Jean-Jacques ULg; De Geetere, L.; Vermeir, G.

in Proceedings of the Institute of Acoustics (2003), 25(5), 67-74

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See detailCalculation of the scattering coefficient of a sine-shaped surface by using the BEM method
De Geetere, L.; Embrechts, Jean-Jacques ULg; Vermeir, G.

in Proceedings of the Institute of Acoustics (2003), 25(5), 75-83

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See detailCalculation of Thermoelectric Properties from First-Principles
Xu, Bin ULg; Verstraete, Matthieu ULg

Poster (2012, July)

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See detailCalculation of third order joint acceptance function for line-like structures
Blaise, Nicolas ULg; Canor, Thomas ULg; Denoël, Vincent ULg

in Proceedings of the XIII Conference of the Italian Association for Wind Engineering (2014, June 24)

Detailed reference viewed: 49 (13 ULg)