Statistical study of passive portfolio management of risky assets

In this paper we consider the problem of creating the optimal investment portfolio. We reveal the concept of the securities portfolio and highlight the most significant parameters of its management.We prove the need of diversification. We implement classical Markowitz portfolio theory. Also we consider the features of passive portfolio management

Plaidoyer universitaire pour le rail

[Chapeau] Le réseau ferré en Wallonie s’apparentera bientôt à un train touristique reliant deux gares Calatrava plutôt que d’assurer à chacun le droit à sa mobilité

Governing multicultural Brussels: paradoxes of a multi-level, multi-cultural, multi-national urban anomaly

Updating our earlier work on Brussels as the paradigm of a multi-level, multi-cultural, multi-national city, and in the context of Brussels’s recent troubled emergence as the epicentre of violent conflict between radical political Islam and the West, this paper sets out the paradoxical intersection of national (i.e. Flemish and Francophone), non-national and ethnic minority politics in a city placed as a multi-cultural and multi-national ‘urban anomaly’ at the heart of linguistic struggle of the two dominant Belgian communities. Brussels is one of the three Regions of the Belgian federal model alongside Flanders and Wallonia. It is also an extraordinarily diverse and cosmopolitan city, in which a mixed language Belgian population lives alongside very high numbers of resident non-nationals, including European elites, other European immigrant workers, and immigrants from Africa and Asia. After laying out the complex distribution of power and competences within the Belgian federal structure, we explore whether these structures have worked over the years to include or exclude disadvantaged ethnic groups. To better understand these processes, we introduce our view of the multi-level governance perspective

Sciences, technologies et société : Guide pratique en 250 questions

Nous vivons incontestablement dans une société où les sciences et les technologies jouent un rôle essentiel. Étant donné le nombre grandissant de questions cruciales, possédant un ou plusieurs aspects technoscientifiques, il est nécessaire que chacun puisse se faire une idée, personnelle, mais justifiée. Mais, entre le spécialiste, le technicien et le citoyen, une étape est généralement manquante. Lorsqu’on essaye d’en savoir plus sur une technologie donnée ou un problème scientifique complexe pour essayer d’effectuer des calculs d’ordres de grandeur, on trouve peu de données utiles. C’est le point de départ de cet ouvrage : associer des connaissances suffisantes de notions fondamentales de sciences à des données techniques afin d’en savoir plus sur une technologie donnée ou un problème scientifique complexe C’est donc au travers de 250 questions et réponses que le lecteur pourra appréhender des thématiques aussi diverses que le bâtiment, l’informatique, les énergies ou encore les transports. Ce livre s’adresse à plusieurs catégories de lecteurs. D’abord, au citoyen désireux de se faire une opinion sur certains thèmes à caractère technoscientifique. Au curieux aussi, qui veut savoir sur quoi reposent différentes technologies, quels sont leurs liens et implications avec la société. Aux enseignants, qui trouveront des données numériques, des formules de base pour illustrer leur cours de sciences. La volonté de cet ouvrage est de démontrer qu’il est possible d’appréhender des problèmes de société majeurs, à partir de notions scientifiques vues dans le secondaire. N’est-ce pas une voie à suivre pour recréer une dynamique nouvelle dans l’enseignement des sciences, et pour montrer aux enseignants et aux jeunes l’utilité des cours de sciences ? Ce livre s’adresse aussi à tous ceux qui ont mission d’informer le public. Ils trouveront ici des données, des raisonnements utiles pour, selon leurs propres sources, réévaluer certains chiffres officiels, analyser certains discours techniques ou politiques à l’aide de faits scientifiques et techniques. La plupart des réponses aux 250 questions qui suivent sont donc accessibles au plus grand nombre, ce qui fait de cet ouvrage un guide pratique à l’usage de tous !3e éditio

GNSS meteorology and impact on NRT position

peer reviewedThe analysis of GNSS signal and the use a dense network of ground-based stations allow to measure tropospheric parameters that can be used for near real-time (NRT) meteorological applications (e.g. monitoring of the delay of the neutral atmosphere and the detection of blobs of water vapour). On the other hand, the meteorological activity can impact GNSS positioning solutions. For this reason, NRT indicators of the tropospheric activity related to the disturbance of GNSS signal are required. Using a dense network of GNSS stations, this study presents a new NRT indicator based on the double differences of the ionosphere-free combination. To validate this indicator, the impact of severe weather conditions on RTK positioning solutions is shown

A multicentre survey of antimicrobial resistance in Gram-negative isolates from Belgian intensive care units in 1994-1995

The aim of this prospective study was to evaluate the distribution and antibiotic susceptibility of aerobic Gram-negative bacilli isolated from patients in intensive care units in 18 Belgian hospitals during 1994 and 1995. A standardised method (i.e. the E-test) was used in each center to determine the minimum inhibitory concentrations of 12 major antibiotics against 1435 consecutive, non duplicate, Gram-negative isolates (close to 100 strains per hospital) during a period of 6 months. The isolates were mainly isolated from the lower respiratory tract (57.4%), urinary tract (17.7%), pus (7.9%) or blood specimens (7.8%) and were mainly P. aeruginosa (20.3%), E. coli (19.9%) and Enterobacter spp. (12.6%). Overall inducible Enterobacteriaceae (IE) accounted for 29.8% of all isolates, and E. aerogenes was the most frequently isolated species in this group (27.6%). The overall susceptibility rate (all species confounded) was about 70% to piperacillin, ticarcillin-clavulanic acid and ceftriaxone, 78% to piperacillin-tazobactam; 87% both to ceftazidime and to ciprofloxacin; and 90% to imipenem. Widespread resistance was observed in several IE species to third generation cephalosporins, broad-spectrum penicillins and to ciprofloxacin. By contrast, imipenem and the aminoglycosides still retained excellent activity against most multiresistant species. Although there were wide differences between hospitals in the frequencies of resistance to most antibiotics, these were not related to the types (general vs. university) of hospitals or to the number of beds. Some variations were however observed in the distribution of bacterial species: the prevalence of inducible Enterobacteriaceae was significantly higher in university than in general hospitals and in hospitals located in Brussels and in Wallonia than in the Flanders. Overall few trends in resistance rates were observed in comparison to a similar survey performed in 1991.SCOPUS: ar.jinfo:eu-repo/semantics/publishe