4,436 research outputs found
Machine translation technologies used in online translation industry
The article gives an overview of such machine translation technologies as Rule-based Machine Translation, Statistical Machine Translation, Hybrid Machine Translation as well as of Translation Memory. Peculiarities of their implementation in online translators by different specialized IT companies are also consideredye
Peculiarities of machine translation technologies implementation in major on-line translators: comparative study
The article considers the main existing machine translation technologies and their application in on-line translators by PROMT, Google and Yandex as well as their advantages and disadvantages in terms of output texts qualityye
Light elements in massive single and binary stars
We highlight the role of the light elements (Li, Be, B) in the evolution of
massive single and binary stars, which is largely restricted to a diagnostic
value, and foremost so for the element boron. However, we show that the boron
surface abundance in massive early type stars contains key information about
their foregoing evolution which is not obtainable otherwise. In particular, it
allows to constrain internal mixing processes and potential previous mass
transfer event for binary stars (even if the companion has disappeared). It may
also help solving the mystery of the slowly rotating nitrogen-rich massive main
sequence stars.Comment: 10 pages, 8 figures, to appear in proc. IAU-Symp. 268. C. Charbonnel
et al., eds
Stereotypical risks and threats in the youth’s opinion (diachronic comparative aspect)
The paper reveals the structure of associative fields of words-stimuli "danger", "risk", "threat", fixed in 1988-90 (the materials of "Russian Association Dictionary") and in 2015 (the results of authors’ associative experiment). The obtained results demonstrate the structural stability of these fields diachronically on the one hand and explicit redistribution of "association vectors" within them on the other on
On the relation of Voevodsky's algebraic cobordism to Quillen's K-theory
Quillen's algebraic K-theory is reconstructed via Voevodsky's algebraic
cobordism. More precisely, for a ground field k the algebraic cobordism
P^1-spectrum MGL of Voevodsky is considered as a commutative P^1-ring spectrum.
There is a unique ring morphism MGL^{2*,*}(k)--> Z which sends the class
[X]_{MGL} of a smooth projective k-variety X to the Euler characteristic of the
structure sheaf of X. Our main result states that there is a canonical grade
preserving isomorphism of ring cohomology theories MGL^{*,*}(X,U)
\tensor_{MGL^{2*,*}(k)} Z --> K^{TT}_{- *}(X,U) = K'_{- *}(X-U)} on the
category of smooth k-varieties, where K^{TT}_* is Thomason-Trobaugh K-theory
and K'_* is Quillen's K'-theory. In particular, the left hand side is a ring
cohomology theory. Moreover both theories are oriented and the isomorphism
above respects the orientations. The result is an algebraic version of a
theorem due to Conner and Floyd. That theorem reconstructs complex K-theory via
complex cobordism.Comment: LaTeX, 18 pages, uses XY-pi
A multigroup diffusion solver using pseudo transient continuation for a radiation-hydrodynamic code with patch-based AMR
We present a scheme to solve the nonlinear multigroup radiation diffusion
(MGD) equations. The method is incorporated into a massively parallel,
multidimensional, Eulerian radiation-hydrodynamic code with adaptive mesh
refinement (AMR). The patch-based AMR algorithm refines in both space and time
creating a hierarchy of levels, coarsest to finest. The physics modules are
time-advanced using operator splitting. On each level, separate level-solve
packages advance the modules. Our multigroup level-solve adapts an implicit
procedure which leads to a two-step iterative scheme that alternates between
elliptic solves for each group with intra-cell group coupling. For robustness,
we introduce pseudo transient continuation (PTC). We analyze the magnitude of
the PTC parameter to ensure positivity of the resulting linear system, diagonal
dominance and convergence of the two-step scheme. For AMR, a level defines a
subdomain for refinement. For diffusive processes such as MGD, the refined
level uses Dirichet boundary data at the coarse-fine interface and the data is
derived from the coarse level solution. After advancing on the fine level, an
additional procedure, the sync-solve (SS), is required in order to enforce
conservation. The MGD SS reduces to an elliptic solve on a combined grid for a
system of G equations, where G is the number of groups. We adapt the partial
temperature scheme for the SS; hence, we reuse the infrastructure developed for
scalar equations. Results are presented. (Abridged)Comment: 46 pages, 14 figures, accepted to JC
Visual clues act as a substitute for haptic feedback in robotic surgery
Objective: The lack of haptic feedback (HF) in robotic surgery is one of the major concerns of novice surgeons to that field. The superior visual appearances acquired during robotic surgery may give clues that make HF less important. Methods: We surveyed 52 individuals on their perception of HF during robotic surgery. The first group of 34 surgically inexperienced people used the da Vinci robot for their first time (drylab). The second group included 8 laparoscopic surgeons with experience up to a fifth robotic operation. The third group included 10 surgical experts with substantial experience (150-650 robotic cases). Visual analog assessment was made of perception of HF, how much HF was missed, how much the absence of HF impaired the operators' level of comfort. Robotic experts were asked if complications have occurred as a result of a lack of HF. Results: Of the first group, 50% reported the perception of HF, as did 55% of the second group and 100% of the third group (difference between group 1 and group 3: p<0.05). The first group missed HF for 6.5; the second group for 4.3, and the third group for 4 (difference between groups 1 and 3: p<0.05). The surgical experts claimed to have missed HF for 7.2 s when they first started robotic surgery (Difference to now: p<0.05). The lack of HF caused discomfort for the first group of 4; for the second group of 4,4, and for the third group of 2,6. One complication was reported by the robotic experts as resulting from the lack of HF. Conclusions: The data support the conclusion that even beginners quickly experience the perception of HF when performing robotic surgery. With more experience, perception of HF and the level of comfort with robotic surgery increases significantly. This perception of HF makes "real” HF less important and demonstrates that its importance is overestimated by novices in robotic surger
Progrès récents de l'Imagerie par Résonance Magnétique (IRM) chez le nouveau-né. Recent advances in newborn MRI
International audienceAbstractThe accurate morphological exploration of the brain is a major challenge in neonatology that advances in magnetic resonance imaging (MRI) can now provide. MRI is the gold standard if an hypoxic ischemic pathology is suspected in a full term neonate. In prematures, the specific role of MRI remains to be defined, secondary to US in any case. We present a state of the art of hardware and software technical developments in MRI. The increase in magnetic field strength (3 tesla) and the emergence of new MRI sequences provide access to new information. They both have positive and negative consequences on the daily clinical data acquisition use. The semiology of brain imaging in full term newborns and prematures is more extensive and complex and thereby more difficult to interpret. The segmentation of different brain structures in the newborn, even very premature, is now available. It is now possible to dissociate the cortex and basal ganglia from the cerebral white matter, to calculate the volume of anatomical structures, which improves the morphometric quantification and the understanding of the normal and abnormal brain development. MRI is a powerful tool to analyze the neonatal brain. The relevance of the diagnostic contribution requires an adaptation of the parameters of the sequences to acquire and of the image processing methods.RésuméL’exploration morphologique fine du cerveau est un enjeu majeur en néonatalogie que les avancées de l’imagerie par résonance magnétique (IRM) permettent actuellement. L’IRM est l’examen de choix devant une suspicion de pathologie anoxo-ischémique à terme. Chez le prématuré, la place précise de l’IRM reste à définir, toujours en seconde intention après l’échographie transfontanellaire (ETF). Nous dressons un panorama des évolutions techniques récentes matérielles et logicielles, en IRM. L’augmentation de l’intensité des champs magnétiques (3 teslas) et l’apparition de nouvelles séquences donnent accès à de nouvelles informations. Elles ont des conséquences positives et négatives sur l’acquisition des données en utilisation clinique quotidienne. La sémiologie de l’imagerie cérébrale du nouveau-né et du prématuré est désormais plus riche, plus complexe et donc d’interprétation plus difficile. La segmentation des différentes structures cérébrales devient accessible chez le nouveau-né, même grand prématuré. Il est aujourd’hui possible de dissocier le cortex et les noyaux gris de la substance blanche cérébrale, de calculer des volumes de structures anatomiques, ce qui améliore la quantification morphométrique et la compréhension du développement cérébral normal et pathologique. L’IRM est un outil inégalable et puissant pour l’analyse du cerveau du nouveau-né, dont la pertinence de l’apport diagnostique requiert une adaptation des paramètres des séquences à acquérir et des méthodes de traitement d’images
Neonatal brain MRI: how reliable is the radiologist’s eye?
International audienceAbstractIntroductionWhite matter (WM) analysis in neonatal brain magnetic resonance imaging (MRI) is challenging, as demonstrated by the issue of diffuse excessive high signal intensity (DEHSI). We evaluated the reliability of the radiologist'eye in this context.MethodsThree experienced observers graded the WM signal intensity on axial T2-weighted 1.5T images from 60 different premature newborns on 2 occasions 4 weeks apart with a semi-quantitative classification under identical viewing conditions.ResultsThe intra- and inter-observer correlation coefficients were fair to moderate (Fleiss’kappa between 0.21 and 0.60). ConclusionThis is a serious limitation of which we need to be aware, as it can lead to contradictory conclusions in the challenging context of term-equivalent age brain MRI in premature infants. These results highlight the need for a semiautomatic tool to help in objectively analyzing MRI signal intensity in the neonatal brain
Equation of state SAHA-S meets stellar evolution code CESAM2k
We present an example of an interpolation code of the SAHA-S equation of
state that has been adapted for use in the stellar evolution code CESAM2k. The
aim is to provide the necessary data and numerical procedures for its
implementation in a stellar code. A technical problem is the discrepancy
between the sets of thermodynamic quantities provided by the SAHA-S equation of
state and those necessary in the CESAM2k computations. Moreover, the
independent variables in a practical equation of state (like SAHA-S) are
temperature and density, whereas for modelling calculations the variables
temperature and pressure are preferable. Specifically for the CESAM2k code,
some additional quantities and their derivatives must be provided. To provide
the bridge between the equation of state and stellar modelling, we prepare
auxiliary tables of the quantities that are demanded in CESAM2k. Then we use
cubic spline interpolation to provide both smoothness and a good approximation
of the necessary derivatives. Using the B-form of spline representation
provides us with an efficient algorithm for three-dimensional interpolation.
The table of B-spline coefficients provided can be directly used during stellar
model calculations together with the module of cubic spline interpolation. This
implementation of the SAHA-S equation of state in the CESAM2k stellar structure
and evolution code has been tested on a solar model evolved to the present. A
comparison with other equations of state is briefly discussed. The choice of a
regular net of mesh points for specific primary quantities in the SAHA-S
equation of state, together with accurate and consistently smooth tabulated
values, provides an effective algorithm of interpolation in modelling
calculations. The proposed module of interpolation procedures can be easily
adopted in other evolution codes.Comment: 8 pages, 5 figure
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