997 resultados para Translation dictionaries


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Santamaría, José Miguel; Pajares, Eterio; Olsen, Vickie; Merino, Raquel; Eguíluz, Federico (eds.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Santamaría, José Miguel; Pajares, Eterio; Olsen, Vickie; Merino, Raquel; Eguíluz, Federico (eds.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Santamaría, José Miguel; Pajares, Eterio; Olsen, Vickie; Merino, Raquel; Eguíluz, Federico (eds.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Santamaría, José Miguel; Pajares, Eterio; Olsen, Vickie; Merino, Raquel; Eguíluz, Federico (eds.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Santamaría, José Miguel; Pajares, Eterio; Olsen, Vickie; Merino, Raquel; Eguíluz, Federico (eds.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Santamaría, José Miguel; Pajares, Eterio; Olsen, Vickie; Merino, Raquel; Eguíluz, Federico (eds.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Santamaría, José Miguel; Pajares, Eterio; Olsen, Vickie; Merino, Raquel; Eguíluz, Federico (eds.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Eterio Pajares, Raquel Merino y José Miguel Santamaría (eds.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Eterio Pajares, Raquel Merino y José Miguel Santamaría (eds.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Raquel Merino Álvarez, José Miguel Santamaría, Eterio Pajares (eds.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

More and more users aim at taking advantage of the existing Linked Open Data environment to formulate a query over a dataset and to then try to process the same query over different datasets, one after another, in order to obtain a broader set of answers. However, the heterogeneity of vocabularies used in the datasets on the one side, and the fact that the number of alignments among those datasets is scarce on the other, makes that querying task difficult for them. Considering this scenario we present in this paper a proposal that allows on demand translations of queries formulated over an original dataset, into queries expressed using the vocabulary of a targeted dataset. Our approach relieves users from knowing the vocabulary used in the targeted datasets and even more it considers situations where alignments do not exist or they are not suitable for the formulated query. Therefore, in order to favour the possibility of getting answers, sometimes there is no guarantee of obtaining a semantically equivalent translation. The core component of our proposal is a query rewriting model that considers a set of transformation rules devised from a pragmatic point of view. The feasibility of our scheme has been validated with queries defined in well known benchmarks and SPARQL endpoint logs, as the obtained results confirm.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The field of cavity-optomechanics explores the interaction of light with sound in an ever increasing array of devices. This interaction allows the mechanical system to be both sensed and controlled by the optical system, opening up a wide variety of experiments including the cooling of the mechanical resonator to its quantum mechanical ground state and the squeezing of the optical field upon interaction with the mechanical resonator, to name two.

In this work we explore two very different systems with different types of optomechanical coupling. The first system consists of two microdisk optical resonators stacked on top of each other and separated by a very small slot. The interaction of the disks causes their optical resonance frequencies to be extremely sensitive to the gap between the disks. By careful control of the gap between the disks, the optomechanical coupling can be made to be quadratic to first order which is uncommon in optomechanical systems. With this quadratic coupling the light field is now sensitive to the energy of the mechanical resonator and can directly control the potential energy trapping the mechanical motion. This ability to directly control the spring constant without modifying the energy of the mechanical system, unlike in linear optomechanical coupling, is explored.

Next, the bulk of this thesis deals with a high mechanical frequency optomechanical crystal which is used to coherently convert photons between different frequencies. This is accomplished via the engineered linear optomechanical coupling in these devices. Both classical and quantum systems utilize the interaction of light and matter across a wide range of energies. These systems are often not naturally compatible with one another and require a means of converting photons of dissimilar wavelengths to combine and exploit their different strengths. Here we theoretically propose and experimentally demonstrate coherent wavelength conversion of optical photons using photon-phonon translation in a cavity-optomechanical system. For an engineered silicon optomechanical crystal nanocavity supporting a 4 GHz localized phonon mode, optical signals in a 1.5 MHz bandwidth are coherently converted over a 11.2 THz frequency span between one cavity mode at wavelength 1460 nm and a second cavity mode at 1545 nm with a 93% internal (2% external) peak efficiency. The thermal and quantum limiting noise involved in the conversion process is also analyzed and, in terms of an equivalent photon number signal level, are found to correspond to an internal noise level of only 6 and 4 times 10x^-3 quanta, respectively.

We begin by developing the requisite theoretical background to describe the system. A significant amount of time is then spent describing the fabrication of these silicon nanobeams, with an emphasis on understanding the specifics and motivation. The experimental demonstration of wavelength conversion is then described and analyzed. It is determined that the method of getting photons into the cavity and collected from the cavity is a fundamental limiting factor in the overall efficiency. Finally, a new coupling scheme is designed, fabricated, and tested that provides a means of coupling greater than 90% of photons into and out of the cavity, addressing one of the largest obstacles with the initial wavelength conversion experiment.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present work appertains to a series of investigations in the field of trophodynamics of water bodies conducted by the department of hydrobiology ”Mosrybvtuza” under the leadership of Prof. Director N.S. Gaevska. Usually with quantitative collections of benthos ostracoda are hardly taken account of. But with the employment of special methods it is possible to be convinced that they are encountered in massive numbers. The role of ostracods in the nutrition of fish is recognised as important by many authors. On the question of the feeding of ostracods, in the literature there are only the fragmentary indications about the occurrence in the gut of ostracods of algae (diatoms, desmids) and detritus. The study of the feeding of ostracods was conducted both by the method of dissecting the guts of ostracods taken from natural waters, and by the method of feeding ostracods under laboratory conditions with a variety of food objects. Moreover, with a view to revision of obtained quantitative data, for determination of food requirements of ostracods the respiration method was applied.