680 research outputs found
Methods and Tools for decentralized on farm breeding
This technical booklet describes the possible experimental designs and statistical methods of analysis that can be carried out, according to the objectives and the experimental constraints of the breeding program
nd the farmers’ group. The way to identify and select the most relevant devices and methods is based on a decision tree
Results of a self-triggered prototype system for radio-detection of extensive air showers at the Pierre Auger Observatory
We describe the experimental setup and the results of RAuger, a small
radio-antenna array, consisting of three fully autonomous and self-triggered
radio-detection stations, installed close to the center of the Surface Detector
(SD) of the Pierre Auger Observatory in Argentina. The setup has been designed
for the detection of the electric field strength of air showers initiated by
ultra-high energy cosmic rays, without using an auxiliary trigger from another
detection system. Installed in December 2006, RAuger was terminated in May 2010
after 65 registered coincidences with the SD. The sky map in local angular
coordinates (i.e., zenith and azimuth angles) of these events reveals a strong
azimuthal asymmetry which is in agreement with a mechanism dominated by a
geomagnetic emission process. The correlation between the electric field and
the energy of the primary cosmic ray is presented for the first time, in an
energy range covering two orders of magnitude between 0.1 EeV and 10 EeV. It is
demonstrated that this setup is relatively more sensitive to inclined showers,
with respect to the SD. In addition to these results, which underline the
potential of the radio-detection technique, important information about the
general behavior of self-triggering radio-detection systems has been obtained.
In particular, we will discuss radio self-triggering under varying local
electric-field conditions.Comment: accepted for publication in JINS
Europium(II) Compounds: Simple Synthesis of a Molecular Complex in Water and Coordination Polymers with 2,2'-Bipyrimidine Mediated Ferromagnetic Interactions
International audienceReaction between EuCl2 and 2,2'-bipyrimidine (bpm) in de-oxygenated water afforded a cationic molecular complex [EuCl(bpm)2(H2O)4][Cl]∙H2O (1). When performed in an organic solvent such as THF or methanol, the same reaction yielded a 3-dimensional coordination polymer of formula [EuCl2(bpm)(MeOH)0.5] (2) in which both bpm and the chloride ions act as linkers between the Eu(II) ions. Upon replacing Cl- by I-, two coordination polymers of formula {[Eu(bpm)2(H2O)3][I]2*0.5bpm}∞ (3) and {[Eu(I)(bpm)(MeOH)]- [I]}∞ (4) were obtained from reaction in water and methanol, respectively. All these compounds were characterized by X-ray crystallography. Investigations of the magnetic properties revealed a weak antiferromagnetic coupling in 2, while 3 and 4 showed a weak ferromagnetic coupling at low temperature
Methods and tools for decentralized on farm breeding
This technical booklet describes the possible experimental designs and statistical methods of analysis that can be carried out, according to the objectives and the experimental constraints of the breeding program and the farmers’ group. The way to identify and select the most relevant devices and methods is based on a decision tree
Decisiveness of Stochastic Systems and its Application to Hybrid Models (Full Version)
In [ABM07], Abdulla et al. introduced the concept of decisiveness, an
interesting tool for lifting good properties of finite Markov chains to
denumerable ones. Later, this concept was extended to more general stochastic
transition systems (STSs), allowing the design of various verification
algorithms for large classes of (infinite) STSs. We further improve the
understanding and utility of decisiveness in two ways. First, we provide a
general criterion for proving decisiveness of general STSs. This criterion,
which is very natural but whose proof is rather technical, (strictly)
generalizes all known criteria from the literature. Second, we focus on
stochastic hybrid systems (SHSs), a stochastic extension of hybrid systems. We
establish the decisiveness of a large class of SHSs and, under a few classical
hypotheses from mathematical logic, we show how to decide reachability problems
in this class, even though they are undecidable for general SHSs. This provides
a decidable stochastic extension of o-minimal hybrid systems.
[ABM07] Parosh A. Abdulla, Noomene Ben Henda, and Richard Mayr. 2007.
Decisive Markov Chains. Log. Methods Comput. Sci. 3, 4 (2007).Comment: Full version of GandALF 2020 paper (arXiv:2001.04347v2), updated
version of arXiv:2001.04347v1. 30 pages, 6 figure
Continental hydrosystem modelling: the concept of nested stream–aquifer interfaces
International audienceCoupled hydrological-hydrogeological models, emphasising the importance of the stream–aquifer interface, are more and more used in hydrological sciences for pluri-disciplinary studies aiming at investigating environmental is-sues. Based on an extensive literature review, stream–aquifer interfaces are described at five different scales: local [10 cm– ∼ 10 m], intermediate [∼ 10 m–∼ 1 km], watershed [10 km 2 – ∼ 1000 km 2 ], regional [10 000 km 2 –∼ 1 M km 2 ] and conti-nental scales [> 10 M km 2 ]. This led us to develop the con-cept of nested stream–aquifer interfaces, which extends the well-known vision of nested groundwater pathways towards the surface, where the mixing of low frequency processes and high frequency processes coupled with the complexity of geomorphological features and heterogeneities creates hy-drological spiralling. This conceptual framework allows the identification of a hierarchical order of the multi-scale con-trol factors of stream–aquifer hydrological exchanges, from the larger scale to the finer scale. The hyporheic corridor, which couples the river to its 3-D hyporheic zone, is then identified as the key component for scaling hydrological pro-cesses occurring at the interface. The identification of the hy-porheic corridor as the support of the hydrological processes scaling is an important step for the development of regional studies, which is one of the main concerns for water practi-tioners and resources managers. In a second part, the modelling of the stream–aquifer in-terface at various scales is investigated with the help of the conductance model. Although the usage of the temperature as a tracer of the flow is a robust method for the assess-ment of stream–aquifer exchanges at the local scale, there is a crucial need to develop innovative methodologies for as-sessing stream–aquifer exchanges at the regional scale. After formulating the conductance model at the regional and inter-mediate scales, we address this challenging issue with the de-velopment of an iterative modelling methodology, which en-sures the consistency of stream–aquifer exchanges between the intermediate and regional scales. Finally, practical recommendations are provided for the study of the interface using the innovative methodology MIM (Measurements–Interpolation–Modelling), which is graphi-cally developed, scaling in space the three pools of methods needed to fully understand stream–aquifer interfaces at vari-ous scales. In the MIM space, stream–aquifer interfaces that can be studied by a given approach are localised. The ef-ficiency of the method is demonstrated with two examples. The first one proposes an upscaling framework, structured around river reaches of ∼ 10–100 m, from the local to the wa-tershed scale. The second example highlights the usefulness of space borne data to improve the assessment of stream– aquifer exchanges at the regional and continental scales. We conclude that further developments in modelling and field measurements have to be undertaken at the regional scale to enable a proper modelling of stream–aquifer exchanges from the local to the continental scale
Data Augmenting Contrastive Learning of Speech Representations in the Time Domain
Contrastive Predictive Coding (CPC), based on predicting future segments of
speech based on past segments is emerging as a powerful algorithm for
representation learning of speech signal. However, it still under-performs
other methods on unsupervised evaluation benchmarks. Here, we introduce
WavAugment, a time-domain data augmentation library and find that applying
augmentation in the past is generally more efficient and yields better
performances than other methods. We find that a combination of pitch
modification, additive noise and reverberation substantially increase the
performance of CPC (relative improvement of 18-22%), beating the reference
Libri-light results with 600 times less data. Using an out-of-domain dataset,
time-domain data augmentation can push CPC to be on par with the state of the
art on the Zero Speech Benchmark 2017. We also show that time-domain data
augmentation consistently improves downstream limited-supervision phoneme
classification tasks by a factor of 12-15% relative
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