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See detailDetermining fine population structure using iterative pruning
Chaichoompu, Kridsadakorn ULg; Yazew, Fentaw Abegaz; Tongsima, Sissades et al

Poster (2017, July 10)

SNP-based information is used in several existing clustering methods to detect shared genetic ancestry or to identify population substructure (Price et al. 2006, Raj et al. 2016). Here, we present an ... [more ▼]

SNP-based information is used in several existing clustering methods to detect shared genetic ancestry or to identify population substructure (Price et al. 2006, Raj et al. 2016). Here, we present an unsupervised clustering algorithm called the iterative pruning method to capture population structure (IPCAPS). Our method supports ordinal data which can be applied directly to SNP data to identify fine-level population structure and it is built on the iterative pruning Principal Component Analysis (ipPCA) algorithm (Intarapanich et al. 2009). The IPCAPS involves an iterative process using multiple splits based on multivariate Gaussian mixture modeling of principal components and Clustering EM estimation as in Lebret et al. (2015). In each iteration, rough clusters and outliers are also identified using our own method called RubikClust. The fixation index (FST) is known to measure a distance between populations and FST = 0.001 may be said to be genetically distinct among the European populations (Tian et al. 2008, Huckins et al. 2014). To observe fine-level population structure using FST, we examined simulated scenarios of one population, 500-8,000 individuals, 5,000-10,000 independent SNPs in HWE (Balding and Nichols 1995), with 100 replicates for each scenario. The simulated SNPs were encoded as additive coding and there was no missing genotype generated. We introduced negative control by subjecting individuals to be separated into two groups using kmeans. We observed that FST values of divided groups were lower than 0.0008, which can be defined as the minimum FST to detect fine-level population structure. To evaluate the performance of our method, we tested different simulated data sets of 2-3 populations, 250 individuals per population, 10,000 independent SNPs in HWE, and FST=[0.0008,0.005], with 100 replicates for each data set. For real-life data sets, we applied the IPCAPS to Thai (Wangkumhang et al. 2013) and HapMap populations. Our method showed that a population classification accuracy was superior to the ipPCA in simulated scenarios of extremely subtle structure (FST=[0.0009,0.005]). In case of the Thai population, results to detect fine-level structure were obtained as well as in case of the HapMap populations. We are convinced that the IPCAPS has a potential to detect fine-level structure and it will be important in molecular reclassification studies of patients once underlying population structure has been removed. [less ▲]

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See detailDimensions adaptatives des fonctionnements pervers et psychopathiques : une approche étho-phénoménologique
Englebert, Jérôme ULg

Conference (2017, July 10)

Notre objectif est de discuter des diagnostics du fonctionnement psychologique pervers et de la personnalité psychopathique. Si les versions récentes du DSM (IV et 5) ignorent ces diagnostics, la pratique ... [more ▼]

Notre objectif est de discuter des diagnostics du fonctionnement psychologique pervers et de la personnalité psychopathique. Si les versions récentes du DSM (IV et 5) ignorent ces diagnostics, la pratique clinique suggère de conserver ces deux entités présentant une finesse psychopathologique plus grande et un pouvoir discriminatif plus important que la personnalité antisociale. Nous souhaitons interroger les dimensions intrinsèquement adaptatives de ces deux entités, mais aussi relever leurs différences sur le continuum de l’adaptation. Nous chercherons, en effet, à démontrer que le principe d'adaptation est une dimension centrale et commune aux deux entités, mais qui « se joue » de façons différentes pour chacune. Le pervers est hyper-adapté à son interlocuteur tout en présentant des moments paradoxaux d'inadaptation. Le psychopathe, avec sa faculté de chosification de l'alter ego et ses compétences émotionnelles paradoxales, présente une adaptation plus solitaire. Dans une perspective inspirée des paradigmes éthologique et phénoménologique, nous tenterons de cerner les différences essentielles entre ces deux modes d’être-au-monde. [less ▲]

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See detailH0LiCOW - I. H0 Lenses in COSMOGRAIL's Wellspring: program overview
Suyu, S. H.; Bonvin, V.; Courbin, F. et al

in Monthly Notices of the Royal Astronomical Society (2017), 468

Strong gravitational lens systems with time delays between the multiple images allow measurements of time-delay distances, which are primarily sensitive to the Hubble constant that is key to probing dark ... [more ▼]

Strong gravitational lens systems with time delays between the multiple images allow measurements of time-delay distances, which are primarily sensitive to the Hubble constant that is key to probing dark energy, neutrino physics and the spatial curvature of the Universe, as well as discovering new physics. We present H0LiCOW (H[SUB]0[/SUB] Lenses in COSMOGRAIL's Wellspring), a program that aims to measure H[SUB]0[/SUB] with <3.5 per cent uncertainty from five lens systems (B1608+656, RXJ1131-1231, HE 0435-1223, WFI2033-4723 and HE 1104-1805). We have been acquiring (1) time delays through COSMOGRAIL and Very Large Array monitoring, (2) high-resolution Hubble Space Telescope imaging for the lens mass modelling, (3) wide-field imaging and spectroscopy to characterize the lens environment and (4) moderate-resolution spectroscopy to obtain the stellar velocity dispersion of the lenses for mass modelling. In cosmological models with one-parameter extension to flat Λ cold dark matter, we expect to measure H[SUB]0[/SUB] to <3.5 per cent in most models, spatial curvature Ω[SUB]k[/SUB] to 0.004, w to 0.14 and the effective number of neutrino species to 0.2 (1σ uncertainties) when combined with current cosmic microwave background (CMB) experiments. These are, respectively, a factor of ˜15, ˜2 and ˜1.5 tighter than CMB alone. Our data set will further enable us to study the stellar initial mass function of the lens galaxies, and the co-evolution of supermassive black holes and their host galaxies. This program will provide a foundation for extracting cosmological distances from the hundreds of time-delay lenses that are expected to be discovered in current and future surveys. [less ▲]

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See detailProbing the atmosphere of a sub-Jovian planet orbiting a cool dwarf
Sedaghati, Elyar; Boffin, Henri M. J.; Delrez, Laetitia et al

in Monthly Notices of the Royal Astronomical Society (2017), 468

We derive the 0.01 $\mu$m binned transmission spectrum, between 0.74 and 1.0 $\mu$m, of WASP-80b from low resolution spectra obtained with the FORS2 instrument attached to ESO's Very Large Telescope. The ... [more ▼]

We derive the 0.01 $\mu$m binned transmission spectrum, between 0.74 and 1.0 $\mu$m, of WASP-80b from low resolution spectra obtained with the FORS2 instrument attached to ESO's Very Large Telescope. The combination of the fact that WASP-80 is an active star, together with instrumental and telluric factors, introduces correlated noise in the observed transit light curves, which we treat quantitatively using Gaussian Processes. Comparison of our results together with those from previous studies, to theoretically calculated models reveals an equilibrium temperature in agreement with the previously measured value of 825K, and a sub-solar metallicity, as well as an atmosphere depleted of molecular species with absorption bands in the IR ($\gg 5\sigma$). Our transmission spectrum alone shows evidence for additional absorption from the potassium core and wing, whereby its presence is detected from analysis of narrow 0.003 $\mu$m bin light curves ($\gg 5\sigma$). Further observations with visible and near-UV filters will be required to expand this spectrum and provide more in-depth knowledge of the atmosphere. These detections are only made possible through an instrument-dependent baseline model and a careful analysis of systematics in the data. [less ▲]

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See detailFranz Brentano vol 1. Sources and Legacy
Boccaccini, Federico ULg; Antonelli, Mauro

Book published by Routledge (2017)

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See detailBrentano and the Primacy of Mental Act
Boccaccini, Federico ULg

in Boccaccini, Federico; Antonelli, Mauro (Eds.) Franz Brentano vol. 2. Intentionality and Philosophy of Mind (2017)

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See detailFranz Brentano. Vol. 2. Intentionality and Philosophy of Mind
Boccaccini, Federico ULg; Antonelli, Mauro

Book published by Routledge (2017)

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See detailFranz Brentano. Vol. 3. Metaphysics, Logic, Epistemology
Boccaccini, Federico ULg; Antonelli, Mauro

Book published by Routledge (2017)

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See detailFranz Brentano vol 4. Ethics, Aesthetics, Religion
Boccaccini, Federico ULg; Antonelli, Mauro

Book published by Routledge (2017)

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See detailOptimising workforce and energy costs by exploiting production flexibility
Cuvelier, Thibaut ULg; Louveaux, Quentin ULg

Conference (2017, July)

In a world where the electricity prices become more and more volatile, notably due to renewable energies, the industry is suffering from cost variations never seen before, especially when electro ... [more ▼]

In a world where the electricity prices become more and more volatile, notably due to renewable energies, the industry is suffering from cost variations never seen before, especially when electro-intensive. Nevertheless, the plants can significantly reduce this impact: some electro-intensive factories could shift their production to time periods where the electricity is cheaper, resulting in large savings. At the same time, the grid operator can remunerate this consumption adaptation as a flexibility service. Our research goal is to optimise the operations of a factory around this flexibility. We compute a production plan that adapts to price forecasts, but also flexibility levers that adjust this plan to react to unexpected price changes. We propose the unifying concept of reservoir to provide sufficiently good models for the plant's processes. Nevertheless, this methodology implies to have frequent production plan changes, which directly impacts the workers, as they may be asked to follow barely predictable schedules. This has a significant detrimental effect on their quality of life. As a consequence, the human aspect of flexibility must also be considered: we seek for production plans that consider both workforce and energy costs, and we then assign workers to work shifts while ensuring their well-being. This HR orientation is the most innovative contribution of this research project. [less ▲]

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See detailA Receding Horizon Approach to Incorporate Frequency Support into the AC/DC Converters of a Multi-Terminal DC Grid
Papangelis, Lampros ULg; Panciatici, Patrick; Debry, Marie-Sophie et al

in Electric Power Systems Research (2017)

This paper proposes a novel control scheme for provision of frequency support among asynchronous AC areas through HVDC grids. It is based on local controllers, each acting on a voltage source converter ... [more ▼]

This paper proposes a novel control scheme for provision of frequency support among asynchronous AC areas through HVDC grids. It is based on local controllers, each acting on a voltage source converter, using local measurements only, and supporting frequency of the adjacent AC area after a significant disturbance. The new discrete control is combined with the existing DC voltage droop technique. The formulation, inspired of Receding Horizon Control, enables providing to the AC area the desired frequency support, while at the same time taking into account various constraints, such as maintaining the DC voltage between secure operating limits. Examples obtained from a test system with a five-terminal DC network connecting two asynchronous areas demonstrate the effectiveness and robustness of the proposed control scheme in various scenarios, with emphasis on component failures. [less ▲]

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See detailReinforcement Learning for Electric Power System Decision and Control: Past Considerations and Perspectives
Glavic, Mevludin ULg; Fonteneau, Raphaël ULg; Ernst, Damien ULg

in The 20th World Congress of the International Federation of Automatic Control, Toulouse 9-14 July 2017 (2017, July)

In this paper, we review past (including very recent) research considerations in using reinforcement learning (RL) to solve electric power system decision and control problems. The RL considerations are ... [more ▼]

In this paper, we review past (including very recent) research considerations in using reinforcement learning (RL) to solve electric power system decision and control problems. The RL considerations are reviewed in terms of speci c electric power system problems, type of control and RL method used. We also provide observations about past considerations based on a comprehensive review of available publications. The review reveals the RL is considered as viable solutions to many decision and control problems across di erent time scales and electric power system states. Furthermore, we analyse the perspectives of RL approaches in light of the emergence of new-generation, communications, and instrumentation technologies currently in use, or available for future use, in power systems. The perspectives are also analysed in terms of recent breakthroughs in RL algorithms (Safe RL, Deep RL and path integral control for RL) and other, not previously considered, problems for RL considerations (most notably restorative, emergency controls together with so-called system integrity protection schemes, fusion with existing robust controls, and combining preventive and emergency control). [less ▲]

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See detailFreeplay-induced limit cycle oscillation mitigation using linear and nonlinear tuned vibration absorbers
Verstraelen, Edouard ULg; Kerschen, Gaëtan ULg; Dimitriadis, Grigorios ULg

in Proceeding of the IFASD 2017 Conference (2017, July)

Structural nonlinearities such as freeplay in control surface bearings and actuators or in connections between wings and external payloads sometimes lead to aeroelastic limit cycle oscillations at ... [more ▼]

Structural nonlinearities such as freeplay in control surface bearings and actuators or in connections between wings and external payloads sometimes lead to aeroelastic limit cycle oscillations at airspeeds lower than the linear flutter speed of the aircraft. In parallel, numerous studies demonstrated the potential of linear and nonlinear tuned vibration absorbers to increase the flutter speed of linear and continuously hardening aeroelastic systems such as two-degree- of-freedom wings or long span bridges. In this work, the effect of linear and nonlinear tuned vibration absorbers is studied on a wing with pitch plunge and control surface deflection degrees of freedom and with freeplay in pitch. Depending on the tuning of the linear absorber, the linear flutter speed of the system can be increased by 10% or the onset of limit cycle oscillations due to the freeplay can be delayed by 7.7% and their amplitude can be significantly decreased. The addition of cubic hardening forces on the absorber can further decrease the limit cycle amplitude in a limited airspeed range at the cost of an increase in limit cycle amplitude in another airspeed range. Conversely, the addition of a freeplay hardening force on the absorber can decrease the limit cycle amplitude without any detrimental effect. [less ▲]

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See detailThe grammaticalization of Russian taxonomic nouns
Kolyaseva, Alena ULg

Conference (2017, July)

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See detailWEATHERING ON THE DEVONIAN SLATES AND CHARACTERIZATION OF A BENTONITE LAYER IN THE WESTERWALD (GERMANY)
Fontaine, François ULg; Hamaekers, Helen; Hoffmann, Andreas et al

Conference (2017, July)

The Westerwald region is one of the largest and oldest clay mining areas of Germany. Those deposits were formed during the Eocene and Oligocene as a result of the weathering, erosion and redeposition of ... [more ▼]

The Westerwald region is one of the largest and oldest clay mining areas of Germany. Those deposits were formed during the Eocene and Oligocene as a result of the weathering, erosion and redeposition of Devonian rocks. During the Miocene, intense volcanic activities led to a large basalt cover, protecting the clays from the erosion. The two main goals of this study are first to improve the knowledge on the weathering processes of the Devonian slates that led to the current setting of those clay deposits by studying the mineralogical and chemical composition of the clays with depth. The second goal is to characterize a bentonite layer underneath the Miocene basalt cover using quantitative X-ray diffraction, chemical analysis, BET, cation exchange capacity and scanning electron microscope. A 20 meter deep quarry mining the Devonian bedrock in southern Westerwald has been sampled on its entire depth. The XRD results show no significant variations of the mineralogy with depth, except for the phyllosilicates. The minerals of the < 2 μm fraction are illite, kaolinite, smectite and mixed-layers minerals (vermiculite-chlorite and illite-chlorite). The proportions of the minerals in the mixed-layers chlorite-vermiculite vary with depth. At the bottom of the quarry, the proportion of vermiculite is very low while in the top, the proportion of vermiculite is higher. This is explained by the degree of the weathering, logically more intense at the top of the quarry. Trace elements compositions are currently being investigated. A 3 meter thick greenish to brownish bentonite layer has been found in the eastern part of the Westerwald region. The XRD performed on different samples of this bentonite shows a relatively heterogeneous composition: montmorillonite (60-80%), kaolinite (5-12%), illite (0-7%), goethite (2-15%), talc (0-10%), K-feldspars (0-7%), plagioclase (0-4%) and traces of amphibole and pyroxene. This bentonite is probably the result of the weathering of volcanic ashes. Since there are not many outcrops of this bentonite layer, its spatial distribution is studied by drilling. [less ▲]

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See detailSpecular sets
Berthé, Valérie; De Felice, Clelia; Delecroix, Vincent et al

in Theoretical Computer Science (2017), 684

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See detailStable isotopes reveal effects of environmental changes on ecological niches of Iphimediidae amphipods
Michel, Loïc ULg; d'Udekem d'Acoz, Cédric; Frederich, Bruno ULg et al

Poster (2017, July)

When faced with environmental changes, organisms are expected to have some intrinsic ability to adapt through ecological plasticity. However, this process is still poorly understood in many Antarctic ... [more ▼]

When faced with environmental changes, organisms are expected to have some intrinsic ability to adapt through ecological plasticity. However, this process is still poorly understood in many Antarctic invertebrates. Here, we focused on Iphimediidae amphipods, as this widely distributed family shows important ecological diversity. In total, 248 amphipods (19 species) from two widely different zones (the West Antarctic Peninsula, or WAP, and Adélie Land, AL) were studied to elucidate how environment can influence ecological niche parameters. Ecological niches were explored using stable isotope ratios of carbon and nitrogen and the SIBER approach (Jackson et al., 2011). The isotopic niche of the whole amphipod assemblage was wider in WAP than in AL. This was true for both total (proxy of the whole range of resources exploited by animals) and the core (proxy of the most commonly used resources) isotopic niches. The ratio between total and core isotopic niches was smaller in WAP than in AL (4.13 vs. 5.74), suggesting that in WAP, animals commonly use a greater relative percentage of the resources to which they have access. Niche modelling at the specific level revealed that this trend was not found in all taxa. For example, niches of Gnathiphimedia sexdentata and Iphimediella microdentata were bigger in WAP than in AL, following the general pattern. On the other hand, niches of Echiniphimedia echinata and E. hodgsoni had the same width in both areas. Moreover, relative niche overlap between these two species was much higher in WAP (42%) than in AL (20%). Our results indicate that the widely different environmental conditions encountered by the animals in these two zones clearly influence their ecology. Overall, Iphimediidae amphipods tend to exploit more resources in WAP, i.e. in the zone where impacts of global change (temperature increase, sea ice cover decrease) are the strongest. Niche overlap between some closely related (i.e. congeneric) species was also more important in WAP. Ultimately, environmental changes in this region might reinforce these trends, which might lead to competition and perturb amphipod community structure. This research was funded by the Belgian Federal Science Policy Office (BELSPO) in the framework of the vERSO and RECTO projects. [less ▲]

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See detailThe role of Gender, Race, and Class in Transnational Political Movements: Mexican and Colombian Women Engaging in Homeland Politics from Europe’s Capital
Lara-Guerrero, Larisa; Vivas Romero, Maria ULg

Conference (2017, June 30)

Drug trafficking is a mounting security problem in Latin America, specifically for the primary producers of narcotics in the region: Mexico and Colombia. The security concern from both countries has ... [more ▼]

Drug trafficking is a mounting security problem in Latin America, specifically for the primary producers of narcotics in the region: Mexico and Colombia. The security concern from both countries has triggered the political and social mobilization of Mexican and Colombian migrants from abroad many of them from the Global City of Brussels. This paper unpacks the motivations and dynamics behind transnational political activism organized by Mexican and Colombian women living in Brussels. By integrating and revising insights from social movements theories, political transnationalism from migration studies and intersectionality studies, this paper elaborates on the role of migrant women organizing and sustaining transnational political movements to change the political conditions of their countries of origin. The ethnographic evidence presented in this paper reveals the importance to recognize the individual level in the analysis of transnational movements. Women are cognitive actors with political ideals and emotions whose political activism is highly influenced by social categorizations such as gender, race, class, and generation. [less ▲]

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