Approximation Algorithms for Multi-Dimensional Vector Assignment Problems

E-print/Working paper (2013)

We consider a special class of axial multi-dimensional assignment problems called multi-dimensional vector assignment (MVA) problems. An instance of the MVA problem is defined by $m$ disjoint sets, each ... [more ▼]

We consider a special class of axial multi-dimensional assignment problems called multi-dimensional vector assignment (MVA) problems. An instance of the MVA problem is defined by $m$ disjoint sets, each of which contains the same number $n$ of $p$-dimensional vectors with nonnegative integral components, and a cost function defined on vectors. The cost of an $m$-tuple of vectors is defined as the cost of their component-wise maximum. The problem is now to partition the $m$ sets of vectors into $n$ $m$-tuples so that no two vectors from the same set are in the same $m$-tuple and so that the total cost of the $m$-tuples is minimized. The main motivation comes from a yield optimization problem in semi-conductor manufacturing. We consider two classes of polynomial-time heuristics for MVA, namely, hub heuristics and sequential heuristics, and we study their approximation ratio. In particular, we show that when the cost function is monotone and subadditive, hub heuristics, as well as sequential heuristics, have finite approximation ratio for every fixed $m$. Moreover, we establish better approximation ratios for certain variants of hub heuristics and sequential heuristics when the cost function is monotone and submodular, or when it is additive. We provide examples to illustrate the tightness of our analysis. Furthermore, we show that the MVA problem is APX-hard even for the case $m=3$ and for binary input vectors. Finally, we show that the problem can be solved in polynomial time in the special case of binary vectors with fixed dimension $p$. [less ▲]

Image de l'autre, lieux communs et stéréotypes: Français et Belges francophones au milieu du XXe siècle

E-print/Working paper (2013)

Fast-evolving weather for the coolest of our two new substellar neighbours

E-print/Working paper (2013)

We present the results of an intense photometric monitoring in the near-infrared (~0.9 microns) with the TRAPPIST robotic telescope of the newly discovered binary brown dwarf WISE J104915.57-531906.1, the ... [more ▼]

We present the results of an intense photometric monitoring in the near-infrared (~0.9 microns) with the TRAPPIST robotic telescope of the newly discovered binary brown dwarf WISE J104915.57-531906.1, the third closest system to the Sun at a distance of only 2 pc. Our twelve nights of photometric time-series reveal a quasi-periodic (P = 4.87+-0.01 h) variability with a maximal peak-peak amplitude of ~11% and strong night-to-night evolution. We attribute this variability to the rotational modulation of fast-evolving weather patterns in the atmosphere of the coolest component (~T1-type) of the binary. No periodic signal is detected for the hottest component (~L8-type). For both brown dwarfs, our data allow us to firmly discard any unique transit during our observations for planets >= 2 Rearth. For orbital periods smaller than ~9.5 h, transiting planets are excluded down to an Earth-size. [less ▲]

Retour au travail après une longue absence...

E-print/Working paper (2013)

When does the Market feel it? Magnitude, speed and persistence of market reactions to of cross-listings

E-print/Working paper (2013)

Compte rendu de Claude Simon: Situations

E-print/Working paper (2013)

Compte rendu du passionnant ouvrage dirigé par Paul Dirkx et Pascal Mougin au sujet de Claude Simon. Esquisse de réflexion sur la clôture du texte.

FAO Training in Crop Yield Forecasting. Crop Yield Forecasting Methodology Enhancement – Remote sensing. Erevan 21 - 25 January 2013.

E-print/Working paper (2013)

Power point presentation of the FAO training "Crop Yield Forecasting Methodology Enhancement – Remote sensing", held in Erevan, Armenia, 21 - 25 January 2013 at ARMSTATEHYDROMET. The main objective of ... [more ▼]

Power point presentation of the FAO training "Crop Yield Forecasting Methodology Enhancement – Remote sensing", held in Erevan, Armenia, 21 - 25 January 2013 at ARMSTATEHYDROMET. The main objective of this training was the improvement of the Crop Yield Forecasting System (CYFS) in Armenia by introducing a new approach for satellite data integration (use of TIMESAT software and METOP AVHRR NDVI images). This training was held in the framework of the "EC/FAO Programme on Information Systems to Improve Food Security Decision-Making in the European Neighbourhood Policy (ENP) East Area GCP/GLO/275/EC". [less ▲]

Warm Spitzer Occultation Photometry of WASP-26b at 3.6{\mu}m and 4.5{\mu}m

E-print/Working paper (2013)

We present new warm Spitzer occultation photometry of WASP-26 at 3.6{\mu}m and 4.5{\mu}m along with new transit photometry taken in the g,r and i bands. We report the first detection of the occultation of ... [more ▼]

We present new warm Spitzer occultation photometry of WASP-26 at 3.6{\mu}m and 4.5{\mu}m along with new transit photometry taken in the g,r and i bands. We report the first detection of the occultation of WASP-26b, with occultation depths at 3.6{\mu}m and 4.5{\mu}m of 0.00126 +/- 0.00013 and 0.00149 +/- 0.00016 corresponding to brightness temperatures of 1825+/-80K and 1725+/-89K, respectively. We find that the eccentricity of the orbit is consistent with a circular orbit at the 1{\sigma} level with a 3{\sigma} upper limit of e < 0.04. According to the activity-inversion relation of Knutson et al. (2010), WASP-26b is predicted to host a thermal inversion. The brightness temperatures deduced from the eclipse depths are consistent with an isothermal atmosphere, although it is within the uncertainties that the planet may host a weak thermal inversion. The data are equally well fit by atmospheric models with or without a thermal inversion. We find that variation in activity of solar-like stars does not change enough over the time-scales of months or years to change the interpretation of the Knutson et al. (2010) activity-inversion relation, provided that the measured activity level is averaged over several nights. Further data are required to fully constrain the thermal structure of the atmosphere because the planet lies very close to the boundary between atmospheres with and without a thermal inversion. [less ▲]

Lettre d’information trimestrielle du projet Développement d’Alternatives Communautaires à l’Exploitation Forestière Illégale

E-print/Working paper (2013)

L’écriture au présent de Thierry Horguelin

E-print/Working paper (2013)

Les notations prises sur le vif par Thierry Horguelin portent un regard singulier sur notre quotidien.

La pratique des inventaires multi-ressources dans les forêts communautaires, ou comment rendre la foresterie communautaire inaccessible aux villageois

E-print/Working paper (2013)

Des inventaires trop complexes imposés aux populations locales risquent de freiner considérablement l'appropriation des futures forêts communautaires gabonaises. La présente fiche technique compare les ... [more ▼]

Des inventaires trop complexes imposés aux populations locales risquent de freiner considérablement l'appropriation des futures forêts communautaires gabonaises. La présente fiche technique compare les avantages et inconvénients des inventaires par poches, des inventaires d'exploitation habituellement réalisés dans les Forêts Communautaires camerounaises et une approche plus simple par normes proposée par l'équipe rédactionnelle. [less ▲]

A Learning Procedure for Sampling Semantically Different Valid Expressions

E-print/Working paper (2013)

La tolérance est coûteuse. On essaye l'intolérance ?

E-print/Working paper (2013)

Le texte a servi à présenter une conférence à des étudiants de bacheliers pédagogiques. Il rappelle, sur un ton informel, mais en essayant d'être rigoureux, la place et l'importance de la tolérance dans ... [more ▼]

Le texte a servi à présenter une conférence à des étudiants de bacheliers pédagogiques. Il rappelle, sur un ton informel, mais en essayant d'être rigoureux, la place et l'importance de la tolérance dans toute conception raisonnable de la vie en société. Il rappelle notamment que si la tolérance n'est pas une vertu "flamboyante", elle constitue un préalable indispensable à d'autres modalités plus exigeantes du vivre ensemble [less ▲]

The agyieus pillar, Egyptian legal papyri, and the cult of Arsinoe Philadephos in the streets of Alexandria

E-print/Working paper (2013)

This paper is divided into two sections. The first aims to offer a thorough discussion of the agyieus and of types of altar for Arsinoe Philadelphos as well as of the offerings devoted to her in the ... [more ▼]

This paper is divided into two sections. The first aims to offer a thorough discussion of the agyieus and of types of altar for Arsinoe Philadelphos as well as of the offerings devoted to her in the Ptolemaic kingdom. The second explores the relationship that exists between the agyieus and the creation of cultic double names of Arsinoe in the streets of Alexandria. By combining the evidence on Arsinoe’s altars with a set of legal papyri attesting her divine names in Alexandria, I argue that in the Ptolemaic capital, the agyieis had a twofold function. They served firstly, as cult places for Arsinoe and secondly, as city landmarks. I will also argue that the second function of the agyieis, as city landmarks, survived the Ptolemaic cult of the Philadelphos and was ultimately preserved in long-lasting toponyms. [less ▲]

From Alexander to the Theoi Adelphoi: Foundation and Legitimation of a Monarchy (332-246 BC)

E-print/Working paper (2013)

The book focuses on the first century of the Macedonian rule over Egypt in order to study how the Ptolemies had their power legitimated in Africa and in the broader Mediterranean context. Literary sources ... [more ▼]

The book focuses on the first century of the Macedonian rule over Egypt in order to study how the Ptolemies had their power legitimated in Africa and in the broader Mediterranean context. Literary sources, inscriptions, papyri, and iconography, both Greek and Egyptian, are used to set an interdisciplinary approach to the topic. Major attention is paid to the social contexts where power legitimating motifs originate and spread as well as to the further history of there themes in later tradition. The book comprises Introduction, 3 sections and 5 chapters. Section I: From Alexander to the Ptolemies. Chapter I: Alexander in Egypt. Focus is on the role of Siwah in the perspective of the Greek, Macedonian, and Egyptian legitimation of Alexander's power in Egypt; particular attention is paid to how legitimating traditions are used and reshaped to the purpose of broadening the limits of Macedonian kingship by depicting Alexander as a Greek hero and as the heir of Pharaohs. Chapter II: In the name of Alexander. The chapter discusses the career of Ptolemy I and his strategies to legitimate his personal power in Egypt and then to establish a new dynasty. Section II: The Political Use of Religious Festivals under Ptolemy II. Chapter III: The Ptolemaia. The chapter discussed the festival Ptolemaia from the point of view of the interaction between political networks and religion. Chapter IV: Anatomy of a Festival: The Grand Procession of Ptolemy II. Focus is on the creation of a political and religious legitimating representation of the dynasty through the scenes of the procession. Detailed discussion of specific traits of Hellenistic religion is provided, especially concerning Dionysus. Section III: Shaping the dynastic couple Chapter V: The Theoi Adelphoi. The political and religious interaction between Ptolemy II and Arsinoe II are discussed to provide a study of the creation of the royal couple as a leading motif in the representation of the dynasty. [less ▲]

L'atelier du réalisateur ou l'usine à répliques. Citations iconographiques chez Luis Buñuel : Francisco de Goya (et d'autres) dans "Belle de jour"

E-print/Working paper (2013)

L’appropriation discursive et pratique du concept de développement durable par des GACEURS et des bénévoles/travailleurs du commerce équitable, vers un imaginaire critique partagé ?

E-print/Working paper (2013)

Ce Working Paper interroge l’existence d’un référentiel critique et argumentatif commun à des initiatives d’Economie Sociale du secteur alimentaire. En utilisant l’appareillage théorique de la « ... [more ▼]

Ce Working Paper interroge l’existence d’un référentiel critique et argumentatif commun à des initiatives d’Economie Sociale du secteur alimentaire. En utilisant l’appareillage théorique de la « sociologie des épreuves », les propos de GACEURS et de bénévoles/salariés du commerce équitable sont analysés afin de voir si le concept de Développement Durable porte en lui un projet sociétal, un référentiel fédérateur, apte à mobiliser des consom’acteurs autour de revendications partagées. L’analyse met en évidence un corpus critique commun articulé autour de quatre axes, dont trois relèvent bien du développement durable, mais nuance ses conclusions au vu de la faiblesse de la grammaire argumentative construite, et des contradictions qui la parcourent. [less ▲]

A Photometric Study of the Hot Exoplanet WASP-19b

E-print/Working paper (2012)

Context: When the planet transits its host star, it is possible to measure the planetary radius and (with radial velocity data) the planet mass. For the study of planetary atmospheres, it is essential to ... [more ▼]

Context: When the planet transits its host star, it is possible to measure the planetary radius and (with radial velocity data) the planet mass. For the study of planetary atmospheres, it is essential to obtain transit and occultation measurements at multiple wavelengths. Aims: We aim to characterize the transiting hot Jupiter WASP-19b by deriving accurate and precise planetary parameters from a dedicated observing campaign of transits and occultations. Methods: We have obtained a total of 14 transit lightcurves in the r'-Gunn, IC, z'-Gunn and I+z' filters and 10 occultation lightcurves in z'-Gunn using EulerCam on the Euler-Swiss telescope and TRAPPIST. We have also obtained one lightcurve through the narrow-band NB1190 filter of HAWK-I on the VLT measuring an occultation at 1.19 micron. We have performed a global MCMC analysis of all new data together with some archive data in order to refine the planetary parameters and measure the occultation depths in z'-band and at 1.19 micron. Results: We measure a planetary radius of R_p = 1.376 (+/-0.046) R_j, a planetary mass of M_p = 1.165 (+/-0.068) M_j, and find a very low eccentricity of e = 0.0077 (+/-0.0068), compatible with a circular orbit. We have detected the z'-band occultation at 3 sigma significance and measure it to be dF_z'= 352 (+/-116) ppm, more than a factor of 2 smaller than previously published. The occultation at 1.19 micron is only marginally constrained at dF_1190 = 1711 (+/-745) ppm. Conclusions: We have shown that the detection of occultations in the visible is within reach even for 1m class telescopes if a considerable number of individual events are observed. Our results suggest an oxygen-dominated atmosphere of WASP-19b, making the planet an interesting test case for oxygen-rich planets without temperature inversion. [less ▲]

Les investisseurs institutionnels dans les Maisons de luxe familiales belges: entre diabolisation et sacralisation

E-print/Working paper (2012)

Abstract : Belgian family luxury Houses are increasingly confrontated to a problem of independence caused by the growing influence of great financial groups and of private investment funds, on the one ... [more ▼]

Abstract : Belgian family luxury Houses are increasingly confrontated to a problem of independence caused by the growing influence of great financial groups and of private investment funds, on the one hand, and by a problem of image due to their Belgian origin, on the other hand. Nevertheless, their growing need for internationalization in order to counter the threats of the market and to seize opportunities leads them to concede one part of their control to institutional investors. The interest of this research is to study the potential impact, as perceived by the leaders of Belgian luxury Houses, of the venue of public institutional investors in their capital structure. We show that this perceived impact oscillates between sacralization and diabolisation of public institutional investors. [less ▲]

Is dark matter made of mirror matter? Evidence from cosmological data

E-print/Working paper (2012)

We present new fast numerical simulations of cosmic microwave background and large scale structure in the case in which the cosmological dark matter is made entirely or partly of mirror matter. We ... [more ▼]

We present new fast numerical simulations of cosmic microwave background and large scale structure in the case in which the cosmological dark matter is made entirely or partly of mirror matter. We consider scalar adiabatic primordial perturbations at linear scales in a flat Universe. The speed of the simulations allows us for the first time to use Markov Chain Monte Carlo analyses to constrain the mirror parameters. A Universe with pure mirror matter can fit very well the observations, equivalently to the case of an admixture with cold dark matter. In both cases, the analyses show a clear indication of the presence of a consistent amount of mirror dark matter, 0.05 < Ω_{mirror} h^2 < 0.12. [less ▲]

Multi-period vehicle loading with stochastic release dates

E-print/Working paper (2012)

This paper investigates a multi-period vehicle loading problem with stochastic information regarding the release dates of items to be transported. The deterministic version of the problem can be ... [more ▼]

This paper investigates a multi-period vehicle loading problem with stochastic information regarding the release dates of items to be transported. The deterministic version of the problem can be formulated as a large-scale set covering problem. Several heuristic algorithms are proposed to generate decision policies for the stochastic optimization model over a long rolling horizon. The resulting policies have been extensively tested on instances which display the main characteristics of the industrial case-study that motivated the research. The tests demonstrate the benefits of the multi-period stochastic model over simple myopic strategies. A simple and efficient heuristic is shown to deliver good policies and to be robust against errors in the estimation of the probability distribution of the release dates. [less ▲]

Evading death by vacuum

E-print/Working paper (2012)

Quantum Mechanics and Quantum Field Theory have forced a reappraisal of the vacuum's exact nature. This is specially true in the Standard Model of particle interactions, where spontaneous symmetry ... [more ▼]

Quantum Mechanics and Quantum Field Theory have forced a reappraisal of the vacuum's exact nature. This is specially true in the Standard Model of particle interactions, where spontaneous symmetry breaking of the electroweak symmetry by the vacuum is mandatory for elementary particles to acquire masses. The mechanism implemented with one scalar doublet leads to a simple vacuum structure at current energies. But, the open possibility that there might be two scalar doublets, enriches the vacuum structure, allowing for the possibility that we might now be in a metastable state, which we dub the panic vacuum. Current experiments at LHC are probing the Higgs particle predicted as a result of the spontaneous symmetry breaking. Remarkably, these experiments may also be useful to dispel the panic vacuum, as we show in a simple model with two doublets and a softly broken U(1) symmetry. [less ▲]

Les Jourdain de la réflexivité : Du bon usage des incidents diplomatiques

E-print/Working paper (2012)

Deregulation of Oxytocin and Vasopressin in Williams Syndrome: A New Model For Exploring Neurogenetics and Neurobiology of Human Social Behavior

E-print/Working paper (2012)

Risk Horizon and Expected Market Returns

E-print/Working paper (2012)

The paper proposes an equilibrium asset pricing model that accounts of the incomplete information on returns distribution and investors' preferences. Only moments up to order four of unknown unconditional ... [more ▼]

The paper proposes an equilibrium asset pricing model that accounts of the incomplete information on returns distribution and investors' preferences. Only moments up to order four of unknown unconditional distribution can be observed, and the model does not impose that portfolio diversi fication or moments preference should hold. Using Chebyshev-type of inequalities, an intuitive risk measure (risk horizon) is introduced with reference to the speed of convergence of a security's mean return to its expectations. By an arbitrage argument, this risk measure is related to the horizon of treasury securities in a system of equations that allows the calibration of the model parameters using term structure information. In particular, the expected return on the market portfolio can be endogenously estimated inside this system. The model calibration on U.S. market data provides plausible parameters estimates and interesting cyclical patterns in the time series of the expected return. The empirical relevance of these estimates is examined with tests of statistical and economic predictive ability for stock excess returns. The results provide signi ficant evidence on the added value of the estimates when compared to popular predictors found in the literature (see a.o. Lettau and Ludvigson, 2001; Rapach and Wohar, 2006; Goyal and Welch, 2008). [less ▲]

NEW CHALLENGES FOR 21ST CENTURY COMPETITION AUTHORITIES

E-print/Working paper (2012)

This paper discusses challenges for competition authorities in the 21st century. Those challenges were identified on the basis of a statistical review of the articles published since January 2011 in five ... [more ▼]

This paper discusses challenges for competition authorities in the 21st century. Those challenges were identified on the basis of a statistical review of the articles published since January 2011 in five major antitrust law journals. The assumption underlying this literature review is that the topics that statistically attract the most the attention from contemporary antitrust scholars are those that will likely constitute the main challenges for 21st century competition authorities. [less ▲]

Lettre d'information trimestrielle N°7 Projet Dacefi

E-print/Working paper (2012)

Conditional asset allocation: Does Market-Wide Liquidity Matter?

E-print/Working paper (2012)

This paper investigates the effect of market-wide liquidity on optimal portfolio allocations across US equity portfolios sorted by size and book-to-market characteristics. In particular, we consider a ... [more ▼]

This paper investigates the effect of market-wide liquidity on optimal portfolio allocations across US equity portfolios sorted by size and book-to-market characteristics. In particular, we consider a single-period investor with a relative risk aversion of 5, and use the nonparametric approach of Brandt (1999) to directly express optimal portfolio weights as functions of market-wide liquidity innovations. We find, first, that the effect of market-wide liquidity is a decreasing function of investment horizon. Second, this effect is stronger in allocations in the small stock portfolio and gets weaker as we move towards the large stock portfolio. Third, conditional allocations in risky asset(s) decrease and exhibit shifts towards more liquid and less risky assets as market-wide liquidity worsens. Overall, our results show that allocations based on market-wide liquidity as a signal capture many phenomena that have been identified by researchers in the US market, such as the so-called “flight-to-safety”, flight-to-quality” and “flight-to-liquidity” episodes. Furthermore, in an out-of-sample test, results demonstrate the superior performance of a strategy based on market-wide liquidity compared to a benchmark strategy. [less ▲]

Les chemins de l’… sont pavés de bonnes intentions

E-print/Working paper (2012)

C’est un fait connu : « Les Liégeois ont été plus que tous les ans domptés. Néanmoins, ils ont toujours relevé leurs crestes » Citation de Michel de L’Hospital, 1558, gravée au fronton du bâtiment de la ... [more ▼]

C’est un fait connu : « Les Liégeois ont été plus que tous les ans domptés. Néanmoins, ils ont toujours relevé leurs crestes » Citation de Michel de L’Hospital, 1558, gravée au fronton du bâtiment de la Cité Administrative de Liège. [less ▲]

Social Security, Ageing and Economic Integration

E-print/Working paper (2012)

The economic and environmental feasibility of biogas buses in Liege

E-print/Working paper (2012)

Every day, many of the students at the University of Liege have to drive to the Sart-Tilman village in order to attend their courses. These movements require many journeys that are responsible for the ... [more ▼]

Every day, many of the students at the University of Liege have to drive to the Sart-Tilman village in order to attend their courses. These movements require many journeys that are responsible for the emission of harmful particles which have a negative impact on climate or human health. The objective of this paper is therefore to analyze the economic and environmental feasibility of using biogas buses for public transport in Liege. The idea of implementing biogas buses is based on the proposed recycling of organic waste by the company INTRADEL, which manages and treats waste in the region. The project is also in line with the willingness of the city of Liege to demonstrate its commitment to environmental issues. The advantages and disadvantages of biogas buses are developed and compared with those of the current diesel bus fleet of the city. The main conclusion of this study is that, while internalizing external costs due to pollution, the use of biogas buses becomes an attractive option compared with classical diesel buses. Nevertheless, it requires investment and might lead to resistance to change. However, it remains a good solution for the reduction of CO2 emissions that are responsible for the greenhouse effect caused by human beings. It is also a good opportunity to market the city, especially within the framework of the application to host the International Exhibition in 2017. [less ▲]

De nieuwe fiscale antimisbruikregel en de gevolgen voor vermogensplanning

E-print/Working paper (2012)

COSMOGRAIL XII: Time delays and 9-yr optical monitoring of the lensed quasar RX J1131-1231

E-print/Working paper (2012)

We present the results from 9 years of optically monitoring the gravitationally lensed z=0.658 quasar RX J1131-1231. The R band light curves of the 4 individual images of the quasar are obtained using ... [more ▼]

We present the results from 9 years of optically monitoring the gravitationally lensed z=0.658 quasar RX J1131-1231. The R band light curves of the 4 individual images of the quasar are obtained using deconvolution photometry, for a total of 707 epochs. Several sharp quasar variability features strongly constrain the time delays between the quasar images. Using three different numerical techniques, we measure these delays for all possible pairs of quasar images, while always processing the 4 light curves simultaneously. For all three methods, the delays between the 3 close images A, B and C are compatible with being 0, while we measure the delay of image D to be 91 days, with a fractional uncertainty of 1.5% (1 sigma), including systematic errors. Our analysis of random and systematic errors accounts in a realistic way for the observed quasar variability, fluctuating microlensing magnification over a broad range of temporal scales, noise properties, and seasonal gaps. Finally, we find that our time delay measurement methods yield compatible results when applied to subsets of the data. [less ▲]

Wanted ! Avez-vous vu ces plantes ? La conservation des plantes messicoles dans le cadre du Programme Agroenvironnemental wallon

E-print/Working paper (2012)

Afin de mener à bien un projet de conservation des plantes messicoles menacées, la Faculté AgroBioTech de Gembloux appelle à diffuser vos observations de terrain au DEMNA

Les Wallons du Wisconsin

E-print/Working paper (2012)

In the middle of the XIXe century, thousands of Walloon left Belgium to settle in Wisconsin, more than 3100 miles away.

Ecaussinnes 2012 - Spring Blues Festival

E-print/Working paper (2012)

Compte-rendu du Spring Blues Festival d'Ecaussinnes, le 19 mai 2012

Do Mutual Fund Investors Still Trust Standard Risk-Adjusted Performance Measures?

E-print/Working paper (2012)

We study the relationship between the past performance of mutual funds and their capital flows (i.e. their subscriptions and redemptions). Testing the most traditional risk-adjusted performance measures ... [more ▼]

We study the relationship between the past performance of mutual funds and their capital flows (i.e. their subscriptions and redemptions). Testing the most traditional risk-adjusted performance measures, we identify the ones which best explain the flows of US equity mutual funds. [less ▲]

Traffic Situation Assessment and Intervention Strategy of a Collision Avoidance System based on Galileo Satellite Positioning

E-print/Working paper (2012)

Nowadays, collision avoidance systems (CAS) are an intensive research topic since the majority of all traffic accidents are collisions that are caused due to inattention or unadjusted driving behavior of ... [more ▼]

Nowadays, collision avoidance systems (CAS) are an intensive research topic since the majority of all traffic accidents are collisions that are caused due to inattention or unadjusted driving behavior of the driver. Up to date prototypic CAS are based on on-board environmental sensors, such as camera or radar systems, that scan the vehicle's surrounding environment in order to assess the situation's hazardousness. The functionality of the used sensors under varying environmental conditions and the limited sensor covering area require an enormous effort to ensure a reliable detection of obstacles, and thus limit the application of the systems. In order to expand the operating field of such systems, a Galileo-based CAS will be developed within the project ‘Galileo above’ (application centre for ground based traffic). This advanced driver assistance system (ADAS) detects surrounding vehicles that are on collision course and reacts autonomously, if the driver does not intervene to avoid the crash. For this purpose the system initiates an emergency stop and/or an emergency steering maneuver. For the development of the CAS the Galileo test centre automotiveGATE in Aldenhoven, Germany will be used. On this test area pseudolites will be installed which provide Galileo-like navigation signals. Thus, the development respectively tuning of Galileo-based vehicle systems will be enabled, so as to have them available on the market when the Galileo satellite system reaches its full operational capability (FOC). The focus of this paper is on the traffic situation assessment and intervention strategy of the CAS. This includes the perception and analysis of the driving situation, the detection of potential collision situation, the definition of an adequate system reaction and the planning of an evasion trajectory. Furthermore, an outlook on the model predictive control for longitudinal and/or lateral control (braking and/or steering maneuver) will be presented. [less ▲]

Extensions of superalgebras of Krichever-Novikov type

E-print/Working paper (2012)

An explicit construction of central extensions of Lie superalgebras of Krichever-Novikov type is given. In the case of Jordan superalgebras related to the superalgebras of Krichever-Novikov type we ... [more ▼]

An explicit construction of central extensions of Lie superalgebras of Krichever-Novikov type is given. In the case of Jordan superalgebras related to the superalgebras of Krichever-Novikov type we calculate a 1-cocycle with coefficients in the dual space. [less ▲]

Briefe an Casanova

E-print/Working paper (2012)

D'une Internationale à l'autre : enquête sur les socialistes européens et le monde des affaires

E-print/Working paper (2012)

Rossano Rosi: triangle amoureux et paternité

E-print/Working paper (2012)

Compte rendu du roman de Rossano Rosi Stabat Pater paru aux Impressions nouvelles en mars 2012.

Newsletter n° 5 - DACEFI 2

E-print/Working paper (2012)

Motionless Memory and Slow Remembering. Towards an Historiographic Understanding of the Imperceptible Movement in 48 by Susana de Sousa Dias

E-print/Working paper (2012)

Heinrich Rickert's Philosophy of History And Its Reception 1896-1936: An Annotated Bibliography

E-print/Working paper (2012)

Annotated bibliography of the main philosophical texts which testify the reception of Heinrich Rickert's much-discussed view on historical sciences from 1896 to 1936.

How to optimally load a set of containers into an aircraft

E-print/Working paper (2012)

Le design du système de contrôle de gestion dans les PMI tunisiennes: une modélisation contingente

E-print/Working paper (2012)

A l'heure actuelle, il existe relativement peu de recherches qui traitent du système de contrôle de gestion des PME, spécialement dans le contexte tunisien, malgré leur importance économique. La présente ... [more ▼]

A l'heure actuelle, il existe relativement peu de recherches qui traitent du système de contrôle de gestion des PME, spécialement dans le contexte tunisien, malgré leur importance économique. La présente communication vise dès lors à élaborer un modèle théorique expliquant le design du système de contrôle de gestion dans les PMI tunisiennes, au départ d'une analyse de la littérature portant spécifiquement soit sur les PMI tunisiennes, soit sur le système de contrôle de gestion de la PME. Cette étude est réalisée en privilégiant deux angles d'analyse particulièrement importants au vu du contexte tunisien, à savoir la taille de l'entreprise et son positionnement sur le cycle de vie. [less ▲]

Les enjeux prospectifs wallons à la lumière d’un dispositif participatif

E-print/Working paper (2012)

La prospective a souvent recours à la démarche participative. Fréquemment, dans son travail analytique, le prospectiviste fait intervenir les acteurs concernés par le système qu'il examine, que ceux-ci ... [more ▼]

La prospective a souvent recours à la démarche participative. Fréquemment, dans son travail analytique, le prospectiviste fait intervenir les acteurs concernés par le système qu'il examine, que ceux-ci opèrent dans ce système ou qu’ils possèdent une expertise particulière par rapport à celui-ci. Dans la majorité des cas, cette intervention s’effectue au cours de l’exercice prospectif. Le présent working paper expose un autre type de situation : l’intervention et la participation des acteurs se placent ici en amont du travail prospectif, au moment de la délimitation des enjeux et des thématiques à considérer dans le cadre du développement d’un programme de recherche. L'expérience présentée par les auteurs, bien qu’elle recoure à l’utilisation d’un outil relativement classique en prospective, à savoir le Delphi, revêt un aspect original. Développée auprès de deux publics distincts, des équipes de recherche d’une part et des membres de l’administration wallonne, d’autre part, elle a permis d’identifier un certain nombre d’enjeux prospectifs majeurs pour la Wallonie et de définir des objets de recherche en rapport avec ces derniers. L'identification et la présentation de ces enjeux fait l’objet du présent texte. Dans un premier temps, celui-ci se propose de décrire le processus d’identification de ces enjeux et, dans un second temps, d’expliciter la nature de ceux-ci. [less ▲]

Measuring Downside and Extreme Risk Allocation in Equity Hedge Funds

E-print/Working paper (2012)

Dynamic Trading Strategies of Equity Hedge Funds: Empirical evidence on how they adapt to market conditions

E-print/Working paper (2012)