Contingency ranking with respect to overloads in very large power systems taking into account uncertainty, preventive, and corrective actions

in IEEE Transactions on Power Systems (2013)

This paper deals with day-ahead security management with respect to a postulated set of contingencies, while taking into account uncertainties about the next day generation/load scenario. In order to help ... [more ▼]

This paper deals with day-ahead security management with respect to a postulated set of contingencies, while taking into account uncertainties about the next day generation/load scenario. In order to help the system operator in decision making under uncertainty, we aim at ranking these contingencies into four clusters according to the type of control actions needed to cover the worst uncertainty pattern of each contingency with respect to branch overload. To this end we use a fixed point algorithm that loops over two main modules: a discrete bi-level program (BLV) that computes the worst-case scenario, and a special kind of security constrained optimal power flow (SCOPF) which computes optimal preventive/corrective actions to cover the worst-case. We rely on a DC grid model, as the large number of binary variables, the large size of the problem, and the stringent computational requirements preclude the use of existing mixed integer nonlinear programming (MINLP) solvers. Consequently we solve the SCOPF using a mixed integer linear programming (MILP) solver while the BLV is decomposed into a series of MILPs. We provide numerical results with our approach on a very large European system model with 9241 buses and 5126 contingencies. [less ▲]

Les Initiatives populaires de solidarité internationale en Wallonie et à Bruxelles : une autre manière de coopérer avec le Sud ?

in Wintgens, Sophie; Grandjean, Geoffrey (Eds.) Acteurs émergents. Perspectives pour la gouvernance mondiale (2013)

Dans le contexte actuel d’harmonisation de l’aide au développement en vue du renforcement de son efficacité, leitmotiv de l’injonction à la professionnalisation du secteur, cette contribution s’attache à ... [more ▼]

Dans le contexte actuel d’harmonisation de l’aide au développement en vue du renforcement de son efficacité, leitmotiv de l’injonction à la professionnalisation du secteur, cette contribution s’attache à questionner les spécificités des Initiatives Populaires de Solidarité Internationale (IPSI) en régions wallonne et bruxelloise au regard des ONG de Développement (ONGD) agréées par la Direction Générale de la coopération au Développement (DGD). Les IPSI sont des associations dont l’objet social principal est la solidarité internationale mais qui ne sont pas subsidiées de manière récurrente par les pouvoirs publics et fonctionnent donc majoritairement sur fonds propres. Elles résultent de l’engagement bénévole de leurs membres, ceux-ci exerçant ces activités solidaires en-dehors ou en sus de leurs occupations professionnelles officielles. Face aux ONGD, sous-champ professionnel qui se définit comme tel et dont les modalités d’accès sont contrôlées par la DGD, les projets menés par les IPSI questionnent les stratégies de développement actuelles des acteurs non gouvernementaux et la place de ces différents acteurs dans le champ des relations Nord-Sud. Ainsi, après avoir défini la professionnalisation dans le cadre de la coopération belge au développement, nous dresserons des pistes quant au regard que les ONGD portent sur les IPSI et inversement, sur les éléments mis en avant par ces dernières pour justifier leurs pratiques dans le champ de la solidarité internationale. [less ▲]

IDENTIFICATION AND DETERMINATION OF ALKALOIDS IN FUMARIA SPECIES FROM ROMANIA

in Digest Journal of Nanomaterials and Biostructures (2013), 8(2), 817-824

The neural correlates of recollection and familiarity during aging

Poster (2013)

Chronic exercise differentially impacts perceptual or motor inhibition as a function of age: a cross-sectional study

Poster (2013)

Le rôle de la qualité de la trace mnésique en oubli dirigé: une comparaison de participants jeunes et âgés lors de la procédure item

Conference (2013)

Hemodynamic comparison of restrictive mitral valve annuloplasty and mitral valve replacement for ischemic mitral regurgitation

in Circulation (2013)

Cross-Border Loss Compensation: State and Critique of the Judicature

in Richelle, Isabelle; Traversa, Edoardo; Schön, Wolfgang (Eds.) Allocating Taxing Powers within the European Union (2013)

- Addresses key issues for the allocation of taxing powers in the European Union - Looks at fundamental questions of direct taxation - Covers a broad range of aspects such as limited tax liability, losses ... [more ▼]

- Addresses key issues for the allocation of taxing powers in the European Union - Looks at fundamental questions of direct taxation - Covers a broad range of aspects such as limited tax liability, losses or transfer pricing The contributions to this volume try to overcome the traditional approach of the judicature of the European Court of Justice regarding the application of the fundamental freedoms in direct taxation that is largely built on a non-discrimination test. In this volume, outstanding authors cover various aspects of the national and international tax order when European law meets domestic taxation. This includes testing traditional pillars of income taxation – ability-to-pay, source and residence, abuse of law, arm’s length standard – with respect to their place in the emerging European tax order as well as substantial matters of co-existence between different tax systems that are not covered by the non-discrimination approach such as mutual recognition, cross-border loss compensation or avoidance of double taxation. The overarching goal is to flesh out the extent to which a substantive “allocation of taxing powers” within the European Union is on its way to a convincing overall framework and to stretch the discussion “beyond discrimination”. [less ▲]

How adaptation strategies of crops could counteract climate change effects? The case of four catchments in Wallonia, Belgium.

in Geophysical Research Abstracts (2013), 15

A sharp increase in extreme heat and drought stress is projected in Belgium by the end of the 21st century, with the potential to significantly reduce crops’ yields under current agricultural practices ... [more ▼]

A sharp increase in extreme heat and drought stress is projected in Belgium by the end of the 21st century, with the potential to significantly reduce crops’ yields under current agricultural practices. This contribution uses an agro-hydrological model in order to assess the potential effects of climate evolution on crop development, yield, and water balance for the main agricultural productions in the Meuse catchment. Erosion risk is also evaluated. We show that grasslands and maize yield decrease and yield variability increases under climate change scenarios. The leaf area index study permits to put in emphasis the earlier start of the vegetation due to warmer climate. It appears that all the sensitive stages occur earlier in the season and that crops are negatively affected by summer drought stress. The better understanding of crops development under evolving climate allows us to propose some changes in agricultural practices and to assess their effectiveness. We evaluate different strategies of adaptation in agricultural practices in order to reduce the potential negative effects of climate change on grasslands and maize production. Adaptation strategies proposed are advanced sowing and harvesting date, introduction of a cover crop for maize and advance in the cutting dates for grasslands. In the particular case of the Vesdre catchment, shifting the growth period of maize permits to avoid the water-deficit period and allow increased yield. This shift makes it possible to introduce a cover crop that will drastically reduce winter soil erosion. For grassland, the adjustment of the cutting dates favored the first cut and the earlier start of the vegetation. The second cut is less profitable due to summer drought stress. The vulnerability assessments focused on the main rotation encountered in the cultivated areas and in the difference in the cover type of these crops. [less ▲]

Middle Palaeolithic Blade Industries and Early Upper Palaeolithic with Carinated Bladelet Cores: New Data from Kulbulak (Uzbekistan)

Conference (2013)