ORBi Collection: Mathematics
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ASSESSMENT OF THE PROPORTIONAL ODDS ASSUMPTION IN LONGITUDINAL STUDIES WITH MISSING ORDINAL OUTCOME DATA
http://hdl.handle.net/2268/171631
Title: ASSESSMENT OF THE PROPORTIONAL ODDS ASSUMPTION IN LONGITUDINAL STUDIES WITH MISSING ORDINAL OUTCOME DATA
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<br/>Author, co-author: Donneau, Anne-Françoise; Mauer, Murielle; Lambert, Philippe; Lesaffre, EmmanuelSIMULATION-BASED COMPARATIVE PERFORMANCE OF MULTIPLE IMPUTATION METHODS FOR INCOMPLETE LONGITUDINAL ORDINAL DATA
http://hdl.handle.net/2268/171630
Title: SIMULATION-BASED COMPARATIVE PERFORMANCE OF MULTIPLE IMPUTATION METHODS FOR INCOMPLETE LONGITUDINAL ORDINAL DATA
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<br/>Author, co-author: Donneau, Anne-Françoise; Mauer, Murielle; Lambert, Philippe; Molenberghs, GeertOlympiades mathématiques belges - Recueil de questions - Tome 8 (2011-2014)
http://hdl.handle.net/2268/171618
Title: Olympiades mathématiques belges - Recueil de questions - Tome 8 (2011-2014)
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<br/>Author, co-author: Dupont, Pascal; Sebille, MichelDouble sweep preconditioner for optimized Schwarz methods applied to the Helmholtz problem
http://hdl.handle.net/2268/171464
Title: Double sweep preconditioner for optimized Schwarz methods applied to the Helmholtz problem
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<br/>Author, co-author: Vion, Alexandre; Geuzaine, ChristopheHomology and Cohomology Computation in Finite Element Modeling
http://hdl.handle.net/2268/171459
Title: Homology and Cohomology Computation in Finite Element Modeling
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<br/>Author, co-author: Pellikka, M.; Suuriniemi, S.; Kettunen, L.; Geuzaine, ChristopheA non-overlapping quasi-optimal optimized Schwarz domain decomposition algorithm for the Helmholtz equation
http://hdl.handle.net/2268/171452
Title: A non-overlapping quasi-optimal optimized Schwarz domain decomposition algorithm for the Helmholtz equation
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<br/>Author, co-author: Boubendir, Yassine; Antoine, Xavier; Geuzaine, ChristopheA DDM double sweep preconditioner for the Helmholtz equation with matrix probing of the DtN map
http://hdl.handle.net/2268/171451
Title: A DDM double sweep preconditioner for the Helmholtz equation with matrix probing of the DtN map
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<br/>Author, co-author: Vion, Alexandre; Bélanger-Rioux, R.; Demanet, L.; Geuzaine, Christophe
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<br/>Commentary: 2013Robustness and efficiency of multivariate coefficients of variation
http://hdl.handle.net/2268/171391
Title: Robustness and efficiency of multivariate coefficients of variation
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<br/>Author, co-author: Aerts, Stéphanie; Haesbroeck, Gentiane; Ruwet, Christel
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<br/>Abstract: The coefficient of variation is a well-known measure used in many fields to compare the variability of a variable in several populations. However, when the dimension is greater than one, comparing the variability only marginally may lead to controversial results. Several multivariate extensions of the univariate coefficient of variation have been introduced in the literature. In practice, these coefficients can be estimated by using any pair of location and covariance estimators. However, as soon as the classical mean and covariance matrix are under consideration, the influence functions are unbounded, while the use of any robust estimators yields bounded influence functions.
While useful in their own right, the influence functions of the multivariate coefficients of variation are further exploited in this talk to derive a general expression for the corresponding asymptotic variances under elliptical symmetry. Then, focusing on two of the considered multivariate coefficients, a diagnostic tool based on their influence functions is derived and compared, on a real-life dataset, with the usual distance-plot.Management of night-only electricity meters
http://hdl.handle.net/2268/171081
Title: Management of night-only electricity meters
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<br/>Author, co-author: Merciadri, Luca
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<br/>Abstract: In this Master’s thesis, the influence of PhotoVoltaic (PV) panels on the distribution network
is explained and related available solutions are also mentioned. We focus on a solution which
consists of optimally using flexible loads. We consider a price signal with two settings: off-
peak tariff and on-peak tariff. Some suitable loads are connected to specific electricity meters,
called ‘night-only meters,’ which allow the consumption of power only in off-peak periods. We
describe the meters’ characteristics and the suitable loads. We also discuss the aspects related
to the practical implementation. Historically, off-peak periods were located during the night
and on-peak periods during the day. Changing the assignment of off-peak periods is an easy
method for distribution system operators to access to the flexibility of small consumers. This
solution can be implemented quickly as the infrastructure needed already exists.
We propose a mixed-integer linear model to assign optimally the off-peak hours so as to
maximize a social welfare. This welfare gathers together the cost of electricity, the financial
losses due to energy curtailments of PV installations and the loads’ wellbeing. Our model
considers automatic tripping of inverters and constraints of the electrical distribution networks.
We target night-only meters, but an extension to dual-hourly meters is also presented.
The results compare the application of the classical pattern against the optimal one for
summer and winter days, the influence of the available variable power for a summer day, and
the use of a monthly-optimal pattern against the classical one for a summer month. The new
disposition of off-peak hours can reduce by 50% the PV energy curtailed in the summer, and can
also help reducing the power flow going through the High-Voltage (HV)/Medium-Voltage (MV)
transformer. The document ends by a cost analysis comparing the homes’ money gains in two
main cases: classical pattern and monthly-optimal one, for a summer month. For each case, the
Distribution System Operator (DSO) either refunds curtailments or not. Four different types
of homes are considered: with or without night-only meters, with or without PV. This analysis
allows to know rapidly who earns money and who looses money by getting plausible values of
electricity bills.Proposition d’ingénierie pour l’étude de la proportionnalité par confrontation à la non-proportionnalité via des manipulations
http://hdl.handle.net/2268/171045
Title: Proposition d’ingénierie pour l’étude de la proportionnalité par confrontation à la non-proportionnalité via des manipulations
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<br/>Author, co-author: Lambrecht, Pauline; Henry, ValérieHigher Symmetries of the conformal Laplacian
http://hdl.handle.net/2268/170910
Title: Higher Symmetries of the conformal Laplacian
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<br/>Author, co-author: Radoux, FabianLaTeX, un peu, beaucoup (2. L'aspect terre-à-terre de la question)
http://hdl.handle.net/2268/170451
Title: LaTeX, un peu, beaucoup (2. L'aspect terre-à-terre de la question)
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<br/>Author, co-author: Dupont, Pascal; Henry, Valérie; Sebille, MichelThe number of structures compatible with any given correlation function
http://hdl.handle.net/2268/170357
Title: The number of structures compatible with any given correlation function
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<br/>Author, co-author: Gommes, CédricIdentifying codes in vertex-transitive graphs
http://hdl.handle.net/2268/170304
Title: Identifying codes in vertex-transitive graphs
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<br/>Author, co-author: Gravier, Sylvain; Parreau, Aline; Rottey, Sara; Storme, Leo; Vandomme, Elise
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<br/>Abstract: We consider the problem of computing identifying codes of graphs and its fractional relaxation. The ratio between the optimal integer and fractional solutions is between 1 and 2 log(|V|) where V is the set of vertices of the graph. We focus on vertex-transitive graphs for which we can compute the exact fractional solution. There are known examples of vertex-transitive graphs that reach both bounds. We exhibit infinite families of vertex-transitive graphs with integer and fractional identifying codes of order |V|^a with a in {1/4, 1/3, 2/5}. These families are generalized quadrangles (strongly regular graphs based on finite geometries). They also provide examples for metric dimension of graphs.LaTeX, un peu, beaucoup (4. Les "équations" et leurs styles)
http://hdl.handle.net/2268/170300
Title: LaTeX, un peu, beaucoup (4. Les "équations" et leurs styles)
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<br/>Author, co-author: Dupont, PascalLaTeX, un peu, beaucoup (3. Le béhaba)
http://hdl.handle.net/2268/170297
Title: LaTeX, un peu, beaucoup (3. Le béhaba)
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<br/>Author, co-author: Dupont, PascalSur les quantifications équivariantes en supergéométrie de contact
http://hdl.handle.net/2268/169770
Title: Sur les quantifications équivariantes en supergéométrie de contact
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<br/>Author, co-author: Nibirantiza, AboubacarHigher Symmetries of the conformal Laplacian
http://hdl.handle.net/2268/169171
Title: Higher Symmetries of the conformal Laplacian
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<br/>Author, co-author: Radoux, FabianLongitudinal quality of life data: a comparison of continuous and ordinal approaches
http://hdl.handle.net/2268/168899
Title: Longitudinal quality of life data: a comparison of continuous and ordinal approaches
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<br/>Author, co-author: Donneau, Anne-Françoise; Mauer, Murielle; Coens, C; Bottomley, A; Albert, AdelinFree Group and Recognizability
http://hdl.handle.net/2268/168800
Title: Free Group and Recognizability
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<br/>Author, co-author: Raskin, Julien
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<br/>Abstract: It is well known that recognizability has many algebraic properties. For example, a subset $L$ of the free monoid $\Sigma^*$ is recognizable if and only if there exists a finite monoid $M$, a subset $P$ of $M$ and a morphism $f : \Sigma^* \to M$ such that $L = f^{-1}(P)$. These properties allow us to easily define a concept of recognizability in non-free monoids or even in other algebraic structures, such as groups.
Our aim is to study the recognizable subsets of the free group $F_X$ generated by $X$. A classical construction of the latter shows that it can be seen as a subset of the free monoid $(X \cup X')^*$, where $X'$ is a set of formal inverses of elements of $X$, endowed with an ad hoc operation. When $X$ is finite, it appears that $F_X$ is a recognizable language of this monoid. It is then natural to wonder if there is a link between recognizability in $F_X$ and recognizability in $(X \cup X')^*$. We show that every recognizable language of $F_X$ is recognizable in $(X \cup X')^*$, and that we can define a class of automata that recognize the recognizable languages of $F_X$.