21,487 research outputs found
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Marion most bold : feminine transgression in the greenwood
In my project, I focus on the role and depiction of women found in the Robin Hood greenwood: specifically, those of Maid Marian. Maid Marian rarely appears in early Robin Hood texts, and especially not in a capacity in which she herself speaks, so it is striking that today she has become almost as synonymous with the greenwood in Robin Hood tales as the man himself. Indeed, one of the rare instances in which Marian plays a lead role occurs in the seventeenth-century ballad “Robin Hood and Maid Marian,” which appears in only one manuscript, after the original Robin Hood ballads of the Middle Ages, and does not seem to have been popular. This seventeenth-century ballad allots Maid Marian an agency typically reserved only for Robin’s merry men. Though I agree that Marian exhibits certain transgressive behaviors, especially in “Robin Hood and Maid Marian,” by the end of Robin Hood texts—medieval, early modern, or otherwise—though the space of the greenwood allows a certain level of freedom for the men in the texts, the “good” women in the Robin Hood texts remain noble ladies who still act as they ought to even though they live outside the confines of civilized society. The same social rules of urban society continue to apply to them, and even in the few cases where the women get to demonstrate more traditionally masculine qualities, they still must end up back in their proper role at the end of the Robin Hood ballad or play.Englis
Simple permutations poset
This article studies the poset of simple permutations with respect to the
pattern involvement. We specify results on critically indecomposable posets
obtained by Schmerl and Trotter to simple permutations and prove that if
are two simple permutations such that then there
exists a chain of simple permutations such that - or 2
when permutations are exceptional- and . This
characterization induces an algorithm polynomial in the size of the output to
compute the simple permutations in a wreath-closed permutation class.Comment: 15 page
Noise in superconductor-quantum dot-normal metal structures in the Kondo regime
We consider a N-dot-S junction in the Kondo regime in the limit where the
superconducting gap is much smaller than the Kondo temperature. A
generalization of the floating of the Kondo resonance is proposed and many body
corrections to the average subgap current are calculated. The zero frequency
noise is computed and the Fano factor sticks to the value 10/3 for all voltages
below the gap. Implications for finite frequency noise are briefly discussed
Exact calculation of current correlations and admittance in the fractional quantum Hall regime
In this work, we focus on the finite frequency current-current correlations
between edge states in a fractional quantum Hall two dimensional gas and on
their relations to the quantum admittance. Using a refermionization method, we
calculate these quantities within the same framework. Our results apply
whatever the values of backscattering amplitude, frequency, voltage and
temperature, allowing us to reach different regimes. Auto-correlations and
cross-correlations exhibit distinct frequency dependencies that we discuss in
detail.Comment: 4 pages, 7 figure
Extension of the SAEM algorithm for nonlinear mixed models with two levels of random effects
This article focuses on parameter estimation of multi-levels nonlinear mixed
effects models (MNLMEMs). These models are used to analyze data presenting
multiple hierarchical levels of grouping (cluster data, clinical trials with
several observation periods,...). The variability of the individual parameters
of the regression function is thus decomposed as a between-sub ject variability
and higher levels of variability (for example within-sub ject variability). We
propose maximum likelihood estimates of parameters of those MNLMEMs with two
levels of random effects, using an extension of the SAEM-MCMC algorithm. The
extended SAEM algorithm is split into an explicit direct EM algorithm and a
stochastic EM part. Compared to the original algorithm, additional sufficient
statistics have to be approximated by relying on the conditional distribution
of the second level of random effects. This estimation method is evaluated on
pharmacokinetic cross-over simulated trials, mimicking theophyllin
concentration data. Results obtained on those datasets with either the SAEM
algorithm or the FOCE algorithm (implemented in the nlme function of R
software) are compared: biases and RMSEs of almost all the SAEM estimates are
smaller than the FOCE ones. Finally, we apply the extended SAEM algorithm to
analyze the pharmacokinetic interaction of tenofovir on atazanavir, a novel
protease inhibitor, from the ANRS 107-Puzzle 2 study. A significant decrease of
the area under the curve of atazanavir is found in patients receiving both
treatments
Estimation in the partially observed stochastic Morris-Lecar neuronal model with particle filter and stochastic approximation methods
Parameter estimation in multidimensional diffusion models with only one
coordinate observed is highly relevant in many biological applications, but a
statistically difficult problem. In neuroscience, the membrane potential
evolution in single neurons can be measured at high frequency, but biophysical
realistic models have to include the unobserved dynamics of ion channels. One
such model is the stochastic Morris-Lecar model, defined by a nonlinear
two-dimensional stochastic differential equation. The coordinates are coupled,
that is, the unobserved coordinate is nonautonomous, the model exhibits
oscillations to mimic the spiking behavior, which means it is not of
gradient-type, and the measurement noise from intracellular recordings is
typically negligible. Therefore, the hidden Markov model framework is
degenerate, and available methods break down. The main contributions of this
paper are an approach to estimate in this ill-posed situation and nonasymptotic
convergence results for the method. Specifically, we propose a sequential Monte
Carlo particle filter algorithm to impute the unobserved coordinate, and then
estimate parameters maximizing a pseudo-likelihood through a stochastic version
of the Expectation-Maximization algorithm. It turns out that even the rate
scaling parameter governing the opening and closing of ion channels of the
unobserved coordinate can be reasonably estimated. An experimental data set of
intracellular recordings of the membrane potential of a spinal motoneuron of a
red-eared turtle is analyzed, and the performance is further evaluated in a
simulation study.Comment: Published in at http://dx.doi.org/10.1214/14-AOAS729 the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
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The Rise of Asian American Cinema
This project won second place in the 2017 Signature Course Information Literacy Award. The award recognizes exemplary student work that achieves the learning outcomes of the Signature Course information literacy requirement, that students will be able to create and execute a research strategy, critically evaluate information, and use citations. This paper was self-nominated for the award by Stephanie Adeline, with support from Dr. Charlotte Canning and Dr. Paul Bonin-Rodriguez. It was submitted in their Spring 2016 Signature Course, “Arts, Your Money, and the Nation.” This project was chosen because Stephanie made smart use of sources, and evolved her search technique as she worked on this paper and better understood the information she needed. Her way of connecting art and money necessitated a wide variety of sources. As her professors said “…[Stephanie’s] paper draws on comparative methodologies and makes use of media studies, cultural studies, Asian studies, international relations and history…[drawing on] an expansive body of work from scholarly books and journals in communications, anthropology, and media studies, as well as extensive newspaper articles and the primary readings of the films themselves.”Canning, CharlotteBonin-Rodriguez, PaulUT Librarie
Out-of-equilibrium Kondo Effect in a Quantum Dot: Interplay of Magnetic Field and Spin Accumulation
We present a theoretical study of low temperature nonequilibrium transport
through an interacting quantum dot in the presence of Zeeman magnetic field and
current injection into one of its leads. By using a self-consistent
renormalized equation of motion approach, we show that the injection of a
spin-polarized current leads to a modulation of the Zeeman splitting of the
Kondo peak in the differential conductance. We find that an appropriate amount
of spin accumulation in the lead can restore the Kondo peak by compensating the
splitting due to magnetic field. By contrast when the injected current is
spin-unpolarized, we establish that both Zeeman-split Kondo peaks are equally
shifted and the splitting remains unchanged. Our results quantitatively explain
the experimental findings reported in KOBAYASHI T. et al., Phys. Rev. Lett.
104, 036804 (2010). These features could be nicely exploited for the control
and manipulation of spin in nanoelectronic and spintronic devices.Comment: 6+ pages; 3 figures; final versio
Using NLP to build the hypertextuel network of a back-of-the-book index
Relying on the idea that back-of-the-book indexes are traditional devices for
navigation through large documents, we have developed a method to build a
hypertextual network that helps the navigation in a document. Building such an
hypertextual network requires selecting a list of descriptors, identifying the
relevant text segments to associate with each descriptor and finally ranking
the descriptors and reference segments by relevance order. We propose a
specific document segmentation method and a relevance measure for information
ranking. The algorithms are tested on 4 corpora (of different types and
domains) without human intervention or any semantic knowledge
Adapting a general parser to a sublanguage
In this paper, we propose a method to adapt a general parser (Link Parser) to
sublanguages, focusing on the parsing of texts in biology. Our main proposal is
the use of terminology (identication and analysis of terms) in order to reduce
the complexity of the text to be parsed. Several other strategies are explored
and finally combined among which text normalization, lexicon and
morpho-guessing module extensions and grammar rules adaptation. We compare the
parsing results before and after these adaptations
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