3,603 research outputs found
Changes of scale in the study of the evolution of the genetic variance through selection in Tribolium castaneum
International audienc
CHANGES OF SCALE IN THE STUDY OF THE EVOLUTION OF THE GENETIC VARIANCE THROUGH SELECTION IN TRIBOLIUM CASTANEUM
Sparse Linear Models applied to Power Quality Disturbance Classification
Power quality (PQ) analysis describes the non-pure electric signals that are
usually present in electric power systems. The automatic recognition of PQ
disturbances can be seen as a pattern recognition problem, in which different
types of waveform distortion are differentiated based on their features.
Similar to other quasi-stationary signals, PQ disturbances can be decomposed
into time-frequency dependent components by using time-frequency or time-scale
transforms, also known as dictionaries. These dictionaries are used in the
feature extraction step in pattern recognition systems. Short-time Fourier,
Wavelets and Stockwell transforms are some of the most common dictionaries used
in the PQ community, aiming to achieve a better signal representation. To the
best of our knowledge, previous works about PQ disturbance classification have
been restricted to the use of one among several available dictionaries. Taking
advantage of the theory behind sparse linear models (SLM), we introduce a
sparse method for PQ representation, starting from overcomplete dictionaries.
In particular, we apply Group Lasso. We employ different types of
time-frequency (or time-scale) dictionaries to characterize the PQ
disturbances, and evaluate their performance under different pattern
recognition algorithms. We show that the SLM reduce the PQ classification
complexity promoting sparse basis selection, and improving the classification
accuracy
On Fabry P\'erot Etalon based Instruments. I. The Isotropic Case
Here we assess the spectral and imaging properties of Fabry P\'erot etalons
when located in solar magnetographs. We discuss the chosen configuration
(collimated or telecentric) for both ideal and real cases. For the real cases,
we focus on the effects caused by the polychromatic illumination of the filter
by the irregularities in the optical thickness of the etalon and by deviations
from the ideal illumination in both setups. We first review the general
properties of Fabry P\'erots and we then address the different sources of
degradation of the spectral transmission profile. We review and extend the
general treatment of defects followed by different authors. We discuss the
differences between the point spread functions (PSFs) of the collimated and
telecentric configurations for both monochromatic and (real)
quasi-monochromatic illumination of the etalon. The PSF corresponding to
collimated mounts is shown to have a better performance, although it varies
from point to point due to an apodization of the image inherent to this
configuration. This is in contrast to the (perfect) telecentric case, where the
PSF remains constant but produces artificial velocities and magnetic field
signals because of its strong spectral dependence. We find that the unavoidable
presence of imperfections in the telecentrism produces a decrease of flux of
photons and a shift, a broadening and a loss of symmetrization of both the
spectral and PSF profiles over the field of view, thus compromising their
advantages over the collimated configuration. We evaluate these effects for
different apertures of the incident beam.Comment: 20 pages 22 figures 2 Appendice
JPL Ephemeris Tapes E9510, E9511, and E9512
The first issue of JPL Ephemeris Tapes is described. These tapes carry the positions and velocities of the planets and of the Moon, plus nutations and nutation rates in longitude and obliquity, together with second and fourth modified differences, for the interval December 30, 1949, to January 5, 2000
Simulation of the gas density distribution in the accelerator of the ELISE test facility
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Undying Protests: On Collective Action and Practices of Resistance against Feminicide in Ciudad Juárez
This dissertation project examines the wave of protests and practices of resistance that emerged in response to feminicide—the murder, with state impunity, of women and girls because they are female—in the northern cities of Ciudad Juárez and Chihuahua, Mexico. Its goal is to show how those women who live under extreme regimes of violence contest it since far too often social scientific studies that examine gender-based violence in northern Mexico have sough to understand its social, economic, and political roots. While this is indeed a significant contribution, this study aims to reflect politically on the innovative responses to the increasing normalization of violence and the injurious effects of global capitalism by drawing from the insights of political theory, feminist theory, violence studies and human rights scholarship, which I place in a sustained conversation with anti-feminicide activism. Whereas Ciudad Juárez is commonly described as the world’s capital of women’s dead bodies, this dissertation offers a fresh contribution to the existing femicide/feminicide literature by de-centering the overemphasis on violence in order to propose that we rethink the present context of the city from the standpoint of the protests and practices of resistance. I argue that collective activism in Ciudad Juárez not only offers a powerful critique against the state institutions that produce a systematic culture of impunity, but, more significantly, it represents a concerted effort to find more democratic solutions and alternatives to the problem of generalized violence. Thus, throughout this dissertation I will show that the anti-feminicide protests and practices of resistance developed in Juárez offer new forms of social and political organization that seek to repair state violence while generating global awareness about the persistent problem of feminicide. Therefore, I contend that the anti-feminicide struggle can be better understood through the analysis of four crucial practices: maternal activism, a practice that I term the funeralization of the city, human rights discourse and practice, and the ethics of care. I approach these practices as moments of interruption whereby those women who are more vulnerable to gender-based violence raise awareness about that vulnerability in order to redress it
The action of the sex linked barring gene on Spanish chickens with gold plumage
International audienc
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