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See detailA reinforcement learning based discrete supplementary control for power system transient stability enhancement
Glavic, M.; Ernst, Damien ULg; Wehenkel, Louis ULg

in Engineering Intelligent Systems for Electrical Engineering and Communications (2005), 13(2 Sp. Iss. SI), 81-88

This paper proposes an application of a Reinforcement Learning (RL) method to the control of a dynamic brake aimed to enhance power system transient stability. The control law of the resistive brake is in ... [more ▼]

This paper proposes an application of a Reinforcement Learning (RL) method to the control of a dynamic brake aimed to enhance power system transient stability. The control law of the resistive brake is in the form of switching strategies. In particular, the paper focuses on the application of a model based RL method, known as prioritized sweeping, a method proven to be suitable in applications in which computation is considered to be cheap. The curse of dimensionality problem is resolved by the system state dimensionality reduction based on the One Machine Infinite Bus (OMIB) transformation. Results obtained by using a synthetic four-machine power system are given to illustrate the performances of the proposed methodology. [less ▲]

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See detailAccurate photometric light curves of the lensed components of Q2237+0305 derived with an optimal image subtraction technique: Evidence for microlensing in image A
Moreau, O.; Libbrecht, C.; Lee, D. W. et al

in Astronomy and Astrophysics (2005), 436(2), 479-492

Using an optimal image subtraction technique, we have derived the V and R light curves of the four lensed QSO components of Q2237+0305 from the monitoring CCD frames obtained by the GLITP collaboration ... [more ▼]

Using an optimal image subtraction technique, we have derived the V and R light curves of the four lensed QSO components of Q2237+0305 from the monitoring CCD frames obtained by the GLITP collaboration with the 2.6m NOT telescope in 1999/2000 (Alcalde et al. 2002). We give here a detailed account of the data reduction and analysis and of the error estimates. In agreement with Wozniak et al. (2000a,b), the good derived photometric accuracy of the GLITP data allows to discuss the possible interpretation of the light curve of component A as due to a microlensing event taking place in the deflecting galaxy. This interpretation is strengthened by the colour dependence of the early rise of the light curve of component A, as it probably corresponds to a caustics crossing by the QSO source. [less ▲]

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See detailNon-thermal radio emission from O-type stars. I. HD168112
Blomme, Ronny; Van Loo, S.; De Becker, Michaël ULg et al

in Astronomy and Astrophysics (2005), 436(3), 1033-1040

We present a radio lightcurve of the O5.5 III(f(+)) star HD 168112, based on archive data from the Very Large Array (VLA) and the Australia Telescope Compact Array (ATCA). The fluxes show considerable ... [more ▼]

We present a radio lightcurve of the O5.5 III(f(+)) star HD 168112, based on archive data from the Very Large Array (VLA) and the Australia Telescope Compact Array (ATCA). The fluxes show considerable variability and a negative spectral index, thereby confirming that HD 168112 is a non-thermal radio emitter. The non-thermal radio emission is believed to be due to synchrotron radiation from relativistic electrons that have been Fermi accelerated in shocks. For HD 168112, it is not known whether these shocks are due to a wind-wind collision in a binary system or to the intrinsic instability of the stellar wind driving mechanism. Assuming HD 168112 to be a single star, our synchrotron model shows that the velocity jump of the shocks should be very high, or there should be a very large number of shocks in the wind. Neither of these is compatible with time-dependent hydrodynamical calculations of O star winds. If, on the other hand, we assume that HD 168112 is a binary, the high velocity jump is easily explained by ascribing it to the wind-wind collision. By further assuming the star to be an eccentric binary, we can explain the observed radio variability by the colliding-wind region moving in and out of the region where free-free absorption is important. The radio data presented here show that the binary has a period of between one and two years. By combining the radio data with X-ray data, we find that the most likely period is similar to 1.4 yr. [less ▲]

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See detailLa parité linguistique au sein du conseil des ministres
Reuchamps, Min ULg

Master's dissertation (2005)

Since 1970, the Belgian Constitution requires that the federal Council of Ministers be staffed by an equal number of Dutch-speaking and French-speaking ministers, with the possible exception of the Prime ... [more ▼]

Since 1970, the Belgian Constitution requires that the federal Council of Ministers be staffed by an equal number of Dutch-speaking and French-speaking ministers, with the possible exception of the Prime Minister. This thesis explores the constitutional rule of linguistic parity at the highest level of the state. Using the existing “model of points” and the author’s own “model of the weight of ministerial portfolios”, the study analyses the last twenty-three federal Governments (1970-2007) and shows that both Flemish and Francophone communities benefit from the parity: the former because it usually receives an extra minister –the Prime Minister– as well as more Secretaries of State and ensures a similar protection for its minority in Brussels; the latter because it enjoys a symbolic as well as a political guarantee of equal representation. Above all, the Council of Ministers is not only numerically well-balanced but also –and chiefly– politically well-balanced. [less ▲]

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See detailOpen Linking et OpenURL
Mottet, Philippe ULg

in Cahiers de la Documentation = Bladen voor Documentatie (2005), 59(2), 35-47

Les notions d’Open Linking, d’OpenURL, de sensibilité au contexte ou de copie appropriée sont largement répandues désormais dans le monde de l’information scientifique, même si on ne sait pas toujours ... [more ▼]

Les notions d’Open Linking, d’OpenURL, de sensibilité au contexte ou de copie appropriée sont largement répandues désormais dans le monde de l’information scientifique, même si on ne sait pas toujours précisément ce qui se cache sous cette terminologie un peu mystérieuse. Un système d’Open Linking permet, sur Internet et dans un cadre documentaire, de relier entre elles toutes les informations relatives à un sujet particulier grâce à des adresses URL/URI qui portent le nom d’OpenURL. Ces liens OpenURL sont créés dynamiquement à la suite de re-cherches bibliographiques et permettent de rebondir vers d’autres ressources électroniques proposant des in-formations complémentaires liées à la référence de départ et dont l’accès est autorisé pour l’utilisateur. La norme ANSI/NISO Z39.88 définit la syntaxe des liens OpenURL ainsi que les métadonnées, identifiants et protocoles d’échange de communication qui peuvent y être incorporés. [less ▲]

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See detailFast contingency filtering based on linear voltage drop estimates
Otomega, Bogdan; Van Cutsem, Thierry ULg

(2005, June)

This paper deals with the filtering of harmless contingencies in voltage stability and security analyses. In many systems, a post-contingency load flow allows to identify the contingencies with severe ... [more ▼]

This paper deals with the filtering of harmless contingencies in voltage stability and security analyses. In many systems, a post-contingency load flow allows to identify the contingencies with severe impact on voltage stability, as causing either divergence or large voltage drops. However, for filtering purposes, accurate voltage drops need not be computed; linear estimates obtained from sensitivity formulas are appropriate. For a given contingency, the method used in this paper solves a sparse linear system to update the phase angles, assuming constant voltage magnitudes. Then, assuming constant active power flows in the branches, a second sparse system is solved to update the voltage magnitudes. This yields better accuracy than one full load flow iteration while retaining the sparse structure of a decoupled formulation. For contingency analysis, the incidents are filtered by comparing the voltage drops to a threshold. For secure power margin computations, the same procedure is used after stressing the system in the specified direction. The method has been tested on a real system where it has been found to combine simplicity of implementation, quality of filtering and computational efficiency. [less ▲]

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See detailQuasi steady-state models for long-term voltage and frequency dynamics simulation
Grenier, Marie-Eve; Lefebvre, Daniel; Van Cutsem, Thierry ULg

(2005, June)

The Quasi Steady-State (QSS) approximation of long-term dynamics relies on time-scale decomposition and consists of replacing faster phenomena by their equilibrium conditions, in order to reduce the ... [more ▼]

The Quasi Steady-State (QSS) approximation of long-term dynamics relies on time-scale decomposition and consists of replacing faster phenomena by their equilibrium conditions, in order to reduce the complexity of the whole model and increase the computation efficiency of time simulations. This paper describes the extension of a QSS model extensively used in long-term voltage stability studies, to readily incorporate the frequency dynamics that takes place over the same time scale. This extended QSS model relies on a common-frequency assumption. Its advantages, limitations and possible improvements are discussed through simulation results on the Hydro-Québec system, where it has been compared to full time scale simulations. Disturbances with an impact on either frequency or voltages are considered and the coupling between these two aspects of long-term dynamics is briefly discussed. [less ▲]

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See detailL’enseignement en gestion des risques naturels
Ozer, Pierre ULg

Article for general public (2005)

D’ici l’an 2025, 80% de la population mondiale résidera dans les pays en développement et, d’après les estimations, pas moins de 60% de cette population sera extrêmement vulnérable aux inondations ... [more ▼]

D’ici l’an 2025, 80% de la population mondiale résidera dans les pays en développement et, d’après les estimations, pas moins de 60% de cette population sera extrêmement vulnérable aux inondations, tempêtes violentes, tremblements de terre, etc. [...] [less ▲]

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See detailLe QUEEN MARY 2, le plus grand paquebot au monde
René-Pierre Saint-M'Leux, René-Pierre; Marchal, Jean ULg; Hage, André ULg et al

in Journal des Ingénieurs (Le) (2005), n°95

Le Queen Mary 2 est un paquebot qui détient de nombreux records. C’est le plus grand, le plus haut mais aussi le plus cher bateau pour passagers que l’humanité n’ait jamais construit. En effet, les ... [more ▼]

Le Queen Mary 2 est un paquebot qui détient de nombreux records. C’est le plus grand, le plus haut mais aussi le plus cher bateau pour passagers que l’humanité n’ait jamais construit. En effet, les chiffres qui le caractérisent sont éloquents. Le navire fait 345 m de long, 45 m de large, 62 m de haut, possède 13 ponts, pèse 65 000 tonnes et peut accueillir à son bord plus de 4400 passagers. Il peut naviguer à plus de 29 noeuds (45 km/h), tout en gardant une manoeuvrabilité remarquable. Le Queen Mary 2 est une véritable ville flottante. Il dispose de restaurants, d’une discothèque, d’une salle des douanes, de boutiques et même d’une piste d’athlétisme. Le coût de sa construction s’est élevé à plus de 538 millions €. Il n’a fallu que deux années pour le construire. Plus de 800 entreprises et 20 000 ouvriers se sont mobilisés aux chantiers de St- Nazaire pour lui donner le jour. Il y a plusieurs étapes dans la construction d’un navire. Le chantier commence par la réception, le découpage et l’assemblage des tôles nécessaires à la formation de la structure de la coque. Ces tôles sont ensuite soudées pour constituer des ensembles appelés panneaux. A ce stade, on commence à installer une partie des réseaux électriques et des conduits divers. L’étape suivante est la construction puis l’assemblage des blocs qui sont soudés les uns aux autres jusqu’à former des parties entières du navire. La dernière étape est celle de l’armement, plus communément appelé l’habillage. Elle intervient quand le navire a acquis sa silhouette définitive. C’est la phase où l’on apporte au bateau tous les équipements nécessaires à son utilisation. C’est à ce stade qu’est intervenue une société liégeoise, Disteel Cold [less ▲]

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See detailComparison of the Huygens mission and the SM2 test flight for Huygens attitude reconstruction
Sarlette, Alain ULg; Perez-Ayucar, Miguel; Witasse, Olivier et al

Conference (2005, June)

The Huygens probe is the ESA’s main contribution to the Cassini/Huygens mission, carried out jointly by NASA, ESA and ASI. It was designed to descend into the atmosphere of Titan on January 14, 2005 ... [more ▼]

The Huygens probe is the ESA’s main contribution to the Cassini/Huygens mission, carried out jointly by NASA, ESA and ASI. It was designed to descend into the atmosphere of Titan on January 14, 2005, providing surface images and scientific data to study the ground and the atmosphere of Saturn’s largest moon. In the framework of the reconstruction of the probe’s motions during the descent based on the engineering data, additional information was needed to investigate the attitude and an anomaly in the spin direction. Two years before the launch of the Cassini/Huygens spacecraft, in May 1995, a test probe called SM2 (Special Model 2) was dropped in the Earth’s atmosphere from the balloon launch site of Kiruna, Sweden, to verify proper operation during the descent and especially the parachute deployment sequence. It featured a flight standard structure and DCSS (Descent Control SubSystem) and, unlike the Huygens probe, was fully instrumented to monitor the orientation of the descent module (3-axes accelerometers and gyroscopes). We describe how a comparison between the SM2 test flight and the Huygens mission provides some useful information about the Huygens probe’s behavior. After discussing the spin direction, we focus on the tip and tilt. The final conclusions of this comparison at the time of writing are still of qualitative nature, but the results are a starting point for better interpretation of the engineering data in terms of attitude to derive the probe’s orientation. [less ▲]

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See detailHuygens attitude reconstruction based on flight engineering parameters
Perez-Ayucar, Miguel; Sarlette, Alain ULg; Couzin, Patrice et al

Conference (2005, June)

Huygens is ESA’s main contribution to the joint NASA/ESA/ASI Cassini/Huygens mission to Saturn and its largest moon Titan. The Probe, delivered to the interface altitude of 1270 km above the surface by ... [more ▼]

Huygens is ESA’s main contribution to the joint NASA/ESA/ASI Cassini/Huygens mission to Saturn and its largest moon Titan. The Probe, delivered to the interface altitude of 1270 km above the surface by NASA/JPL Cassini orbiter, entered the dense atmosphere of Titan on 14 January 2005 and landed on the surface after a descent under parachute of slightly less than 2.5 hours. Huygens continued to function after landing for more than 3 hours. Data was transmitted and successfully recovered by Cassini continuously during the parachute descent and for 72 minutes on the surface. Although the Huygens attitude reconstruction based on the flight engineering parameters was not foreseen during the development phase (no gyros were included), a rough descent under parachute and indications of an anomaly in the probe spin direction make the engineering dataset valuable in the frame of the ADRS (Huygens Attitude Determination and Reconstruction Subgroup) as a complement to the scientific measurements. In addition, several scientific teams have a strong interest in understanding the orientation of the probe for interpreting their data, as DISR (Descent Imager and Spectral Radiometer) and HASI-PWA (Huygens Atmospheric Structure Instrument-Permeability, Wave and Altimetry). In this paper we describe the engineering parameters used for the Probe attitude reconstruction (Clausen et al., 2002), namely the radio link AGC (Automatic Gain Control), RASU and CASU (Radial and Central Accelerometer Sensor Units) and RAU (Radar Altimeter Unit). We explain the methodology applied to indirectly infer the attitude information from the measurements of these sensors. We also discuss and present the reconstructed information related to attitude: spin rate and azimuthal position (during the atmospheric descent), and landing orientation. Tip and tilt implications are still being worked at the time of writing. Preliminary data on their behavior is presented. [less ▲]

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See detailCharacterization of the spin and attitude of the ESA Huygens probe during its descent onto Titan using the engineering dataset
Sarlette, Alain ULg

Master's dissertation (2005)

The Huygens probe is the ESA’s main contribution to the Cassini-Huygens mission, carried out jointly by the ESA, the NASA and the ASI. It was designed to descent into the atmosphere of Titan, Saturn’s ... [more ▼]

The Huygens probe is the ESA’s main contribution to the Cassini-Huygens mission, carried out jointly by the ESA, the NASA and the ASI. It was designed to descent into the atmosphere of Titan, Saturn’s largest moon, on January 14, 2005, providing surface images of the farthest object a man-made probe has ever landed on. Its main purpose was to study Titan’s atmosphere during the descent phase. Of course, priority has been given to the scientific instruments for data recovery but a small engineering dataset was also sent back to Earth. The goal of the present work was, using these engineering data, to characterize the instantaneous orientation of the Huygens probe during its descent, in order to allow correct analysis of the scientific data. The methods used concern evaluation of reduced accelerometer data, analysis of the telecommunication link’s power level using the accurately known antenna gain pattern and a comparison between the Huygens mission and the more fully instrumented SM2 test probe which was dropped in the Earth’s atmosphere in 1995. Some basic dynamic modelization has also been done to investigate likely behaviours and try to identify consistent approximations. In addition to this report, the results of my work include Excel r files containing probe orientation (support) data as well as a MATLAB r routine which allows to compute a probe’s azimuth from the (manually pre-processed) telemetry link gain and the positioning dataset. A user-friendly program for the visualization of the evolution of all involved variables - including a 3D probe orientation display - was also planned, but could not be finished since a complete characterization of the probe’s attitude (tilt-related motions) was not achieved yet before writing the present report. As a whole bunch of people spread over the world were working on the subject of the probe’s orientation using different information, the conclusions of all teams had to be compared. This was continually done by e-mail while working on the subject; a final meeting on April 22 & 23, 2005 was meant to clarify the situation before publishing first official results. [less ▲]

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See detailOptimal synthesis of mechanisms using time-varying dimensions and natural coordinates
Collard, Jean-François; Fisette, Paul; Duysinx, Pierre ULg

in Herskowitz, José (Ed.) Proceedings of the 6th World Congress of Structural and Multidisciplinary Optimization (WCSMO6) (2005, June)

This paper presents a simple approach to optimize the dimensions and the positions of 2D mechanisms for path or function-generator synthesis. The proposed method is particularly adapted to assembled ... [more ▼]

This paper presents a simple approach to optimize the dimensions and the positions of 2D mechanisms for path or function-generator synthesis. The proposed method is particularly adapted to assembled mechanisms since time-varying dimensions always satisfy the assembly conditions which may represent a real difficulty when dealing with closed-loop mechanisms. The objective is to minimize the strain energy of the bars - considered as flexible - of the mechanism when this one follows perfectly the desired path. Two optimization strategies are developed and criticized. The first one is based on separated optimizations of design parameters and point coordinates. The second one is more global and is performed in two stages : multiple local synthesis are needed first to find the initial point coordinates, and then a global synthesis stage is undertaken to find both the best dimensions and coordinates. The use of natural coordinates is also particularly interesting since the only non linear functions to optimize are distance functions, and the objective function is rather well-conditioned for a gradient-based optimizer. The question of finding the global optimum is addressed and discussed. Since a standard genetic algorithm may fail to find it, a different approach is proposed: exploring the design space to find several local optima among which the designer will choose the most relevant one taking other design constraints into account. A simple technique is applied which consists in running multiple optimization processes starting from uniformly-distributed initial dimensions (full-factorial design of experiments) across the parameter space. Three applications are presented: a simple four-bar path synthesis to illustrate the optimization strategies, a four-bar steering linkage synthesis for function generation – Ackermann relation to highlight the limits of both strategies, and eventually a six-bar steering mechanism to explore the design space and find different local optima. [less ▲]

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See detailContrôle d'un turboréacteur au banc d'essai sur base d'une modélisation en régime transitoire
Thomas, Jean-Philippe ULg

Master's dissertation (2005)

Le service de Turbomachines et Propulsion de l'Université de Liège dispose depuis plusieurs années d'un turboréacteur de laboratoire. Celui-ci consiste en un outil à vocation pédagogique très précieux, et ... [more ▼]

Le service de Turbomachines et Propulsion de l'Université de Liège dispose depuis plusieurs années d'un turboréacteur de laboratoire. Celui-ci consiste en un outil à vocation pédagogique très précieux, et c'est dans ce cadre que ce travail fut réalisé. L'objectif majeur de cette étude était la synthèse et l'application d'un contrôleur digital analogue aux systèmes en usage dans l'aviation civile et militaire. Pour atteindre ce but, plusieurs étapes furent nécessaires. Avant cette entreprise, le banc d'essai disposait d'une mesure de la poussée, effet utile du moteur, fortement parasitée par l'ajout de divers dispositifs au cours des années. Cette mesure étant une information importante, notamment en vue d'une modélisation, et l'effet régulé, il fut nécessaire d'améliorer le système existant. Ceci fut réalisé par une démarche technique complète. Un étalonnage du dispositif fut effectué et montra une pleine satisfaction de l'objectif. L'étape suivante fut la modélisation du moteur, pré-requis à toute étude ultérieure. Par une prise en compte des particularités de celui-ci, cette modélisation montra, après un recalage sur base de mesures prises au banc d'essai, une très bonne qualité de prédiction en régime stationnaire. Son extension au régime transitoire permit de modéliser précisément la dynamique liée à la vitesse de rotation. Celle des autres grandeurs fut par contre quantitativement déficiente mais qualitativement cohérente, en traduisant correctement le comportement physique de chacune. Il fut dès lors possible d'exploiter ce modèle pour la synthèse d'un régulateur. Le contrôleur devait répondre à deux objectifs: la diminution du temps de réponse et le respect des limites physiques du moteur. Ceci fut réalisé par la synthèse d'un régulateur comprenant une série de boucles SISO (Single Input Single Output): l'une gérant le contrôle sur la poussée et les autres garantissant chacune le respect d'une limite. L'utilisation de ce dispositif sur le modèle permit la satisfaction des objectifs, y compris en présence de bruit de mesure. La dernière étape du travail devait être l'application de ce contrôleur au banc d'essai. Celui-ci révéla cependant une telle inadaptation à un contrôle précis et rapide que l'objectif dû être orienté vers un contrôle plus simple, éloigné de la théorie précédente, qui autorisa néanmoins un suivi de consigne satisfaisant. Cette démarche permit malgré tout de mettre en exergue les déficiences du banc d'essai en vue d'une amélioration future conséquente, afin de permettre l'application de la théorie développée et d'ouvrir une porte vers un approfondissement du contrôle. [less ▲]

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See detailUne position d'expert: "grand ensemblier"
Semal, Nathalie ULg

Conference (2005, June)

La mise en oeuvre de la norme ISO 14001 ne constitue pas un face à face entre le texte normatif et son usager, l'entreprise. Elle est le plus souvent accompagnée par des experts du conseil en management ... [more ▼]

La mise en oeuvre de la norme ISO 14001 ne constitue pas un face à face entre le texte normatif et son usager, l'entreprise. Elle est le plus souvent accompagnée par des experts du conseil en management environnemental, qui définissent leur position comme celle d'un "grand ensemblier". L'objectif de la communication est d'explorer cette métaphore. Leurs modes d'intervention contribue à insérer la démarche de l'entreprise dans un réseau de relations multiples et hétérogènes. [less ▲]

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See detailAn interior point method based optimal power flow
Capitanescu, Florin ULg; Glavic, Mevludin; Wehenkel, Louis ULg

(2005, June)

This paper deals with the solution of an optimal power flow (OPF) problem by the interior point method (IPM). The latter is a very appealing approach to this nonlinear programming problem due to its speed ... [more ▼]

This paper deals with the solution of an optimal power flow (OPF) problem by the interior point method (IPM). The latter is a very appealing approach to this nonlinear programming problem due to its speed of convergence and ease of handling inequality constraints. Two interior point algorithms are presented and compared: the pure primal-dual and the predictor-corrector. Several implementation aspects of these IPM algorithms are also discussed. The OPF is formulated in rectangular coordinates which confers some significant advantages because generally its objective and constraints are quadratic functions. Among the large variety of OPF objectives, emphasis is put on two classical ones: the minimization of generation cost and the minimization of transmission active power losses. The solution obtained by both algorithms proves to be robust for the two OPF sub-problems (optimization of active power flows and reactive power flows) as well as for a full OPF applied to the former objective, which is unanimously recognized as the hardest problem to solve. Finally, numerical results on three test systems ranging from 60 to 300 buses are provided. [less ▲]

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See detailThe Critical Neighbourhood Range for Asymptotic Overlay Connectivity in Dense Ad Hoc Networks
Calomme, Sandrine; Leduc, Guy ULg

in Challenges in Ad Hoc Networking (2005, June)

We define, for an overlay built on top of an ad hoc network, a simple criterion for neighbourhood: two overlay nodes are neighbours if and only if there exists a path between them of at most R hops, and R ... [more ▼]

We define, for an overlay built on top of an ad hoc network, a simple criterion for neighbourhood: two overlay nodes are neighbours if and only if there exists a path between them of at most R hops, and R is called the (overlay) neighbourhood range. A small R may result in a disconnected overlay, while an unnecessarily large R would generate extra control traffic. We are interested in the minimum R ensuring overlay connectivity, the so-called critical R. We derive a necessary and sufficient condition on R to achieve asymptotic connectivity of the overlay almost surely, i.e. connectivity with probability 1 when the number of overlay nodes tends to infinity, under the hypothesis that the underlying ad hoc network is itself asymptotically almost surely connected. This condition, though asymptotic, sheds some light on the relation linking the critical R to the number of nodes n, the normalized radio transmission range r and the overlay density D (i.e., the proportion of overlay nodes). This condition can be considered as an approximation when the number of nodes is large enough. Since r is considered as a function of n, we are able to study the impact of topology control mechanisms, by showing how the shape of this function impacts the critical R. [less ▲]

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See detailProspective issues for error detection
Blavier, Adelaïde ULg; Rouy, Emmanuelle ULg; Nyssen, Anne-Sophie ULg et al

in Ergonomics (2005), 48(7), 758-781

Error detection has not received much attention from the scientists since human error has been shown as the main cause of accident in complex systems. However, reducing the consequences of error depends ... [more ▼]

Error detection has not received much attention from the scientists since human error has been shown as the main cause of accident in complex systems. However, reducing the consequences of error depends largely on error detection. The goal of this paper is to synthesize the existing scientific knowledge on error detection, mostly based on studies conducted in laboratory or self reporting and to complete it through the analysis of a corpus of cases collected in a complex system: anaesthesia, in order to better describe how this knowledge can be used to improve our understanding of error detection modes. We used an anaesthesia accident reporting system we developed and organized at two Belgium University Hospitals to collect information about the error detection patterns. Results show that detection of errors principally occurred through standard check. We found significant relationships between the type of error, the type of error detection pattern, and the training level of the anaesthetist who committed the error. [less ▲]

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See detailApplication of a novel oscillatory flow screening micro-reactor to a biotransformation in a two-phase medium
Vicente, A.; Reis, N.; Nobre, C. et al

in Biochemical engineering : frontiers and advances in biotechnology, biological and biomolecular engineering : abstracts”. [S.n. : s.l.] (2005, June)

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