15,640 research outputs found
Self-referenced fibre-optic sensor for liquid detection and/or measurement
The optical technology developed by the Spanish University Carlos III of Madrid is related with carrying out measurements on liquid tanks. It allows detecting the liquid level using light, in an intrinsically safe way, without the risk of explosion of the electronic type techniques. We are looking for the collaboration of companies devoted to the development of instrumentation systems, specifically instrumentation for the storage and distribution of flammable liquids, fuel tanks manufacturers, as well as instrumentation for aircrafts and vehicles.Contrato Programa de Comercialización e Internacionalización. Sistema Regional de Investigación Científica e Innovación Tecnológica. (Comunidad de Madrid; Universidad Carlos III de Madrid
NUESTRA HISTORIA APENAS COMIENZA… UNIDAD ACADÉMICA PROFESIONAL ACOLMAN
La Universidad en su misión de llevar el conocimiento, ciencia y tecnología a otras
zonas, visualiza la creación de un nuevo espacio académico que atienda las
demandas e interés de la población mexiquense, al instaurar un nuevo campus en
nuestra entidad. A solicitud del Presidente del H. Ayuntamiento del Municipio de
Acolman Lic. Vicente Anaya Aguilar (2012-2015), se realizó el estudio de factibilidad
permitiendo identificar las necesidades de la población, y es así como Secretaria de
Docencia, somete al H. Consejo Asesor Universitario el proyect
Distance-based kernels for real-valued data
We consider distance-based similarity measures for real-valued vectors of interest in kernel-based machine learning algorithms. In particular, a truncated Euclidean similarity measure and a self-normalized similarity measure related to the Canberra distance. It is proved that they are positive semi-definite (p.s.d.), thus facilitating their use in kernel-based methods, like the Support Vector Machine, a very popular machine learning tool. These kernels may be better suited than standard kernels (like the RBF) in certain situations, that are described in the paper. Some rather general results concerning positivity properties are presented in detail as well as some interesting ways of proving the p.s.d. property.Peer ReviewedPostprint (author's final draft
Ring Resonators with Sagnac Loops for Photonic Processing in DWDM Backbone Networks
In this paper, optical configurations based on ring resonators (RR) with an internal Sagnac (SG) loop in the feedback path, are analyzed in terms of their amplitude response and dispersive properties for filtering and chromatic dispersion managing in digital transmission systems over amplified single- mode fiber (SMF) spans in DWDM backbone networks. Design issues for the architecture as regards quadratic dispersion and magnitude distortion are provided. The RR+SG compound filter provides frequency tunability of the amplitude and dispersion peaks by adjusting a coupling coefficient of an optical coupler, with no need for using integrated thermo-optic nor current- injection based phase shifters. The configuration can be employed as an additional structure for a general RR-based design and synthesis architecture, allowing bandwidth increase of dispersion compensators and flexibility. The performance of a compound filter consisting of a two RR in series stage and a RR+SG filter are reported as a more compact and effective solution for existing multi-channel SMF backbone links operating at high bit rates. Design guidelines of an integrated ring resonator based on polymer technology for showing feasibility of the proposal is reported.This work was partially supported by Spanish CICYT (TEC2006-13273-C03-03-MIC), European project NoE
EPhoton/One+, CAM (FACTOTEM-CM:S-0505/ESP/000417), FENIS-CCG06-UC3MITIC-0619.Publicad
Radio-frequency ring resonators for self-referencing fiber-optic intensity sensors
A theoretical and experimental study of radiofrequency ring resonators (RR) for referencing and improving the sensitivity of fiber-optic intensity sensors (FOS) is
reported. The separation between lead and transducer losses in the FOS is solved by converting the light intensity fluctuations to be measured into RR losses that produce
high amplitude variations in the proximity of the RR resonance frequencies. Two different self-referencing techniques are developed. Via the definition of the measurement parameter RM , sensor linearity and sensitivity are analyzed. A calibration
using an optical attenuator is reported to validate the model.Publicad
CWDM self-referencing sensor network based on ring resonators in reflective configuration
A new scalable self-referencing sensor network with low insertion losses implemented in Coarse Wavelength Division Multiplexing (CWDM) technology is reported. It allows obtaining remote self-referenced
measurements with a full-duplex fibre downlead up to 35 km long, with no need for optical amplification. Fibre Bragg gratings (FBG) are used in order to achieve a reflective configuration, thus increasing the sensitivity of the optical transducers. Low-cost off-the-shelf devices in CWDM technology can be used to implement and scale the network. Ring resonator (RR) based
incoherent interferometers at the measuring points are used as selfreferencing
technique. A theoretical analysis of power budget of the topology is reported, with a comparison between the proposed network and a conventional star topology. Finally, the new configuration has been experimentally demonstrated.This work has been supported by CICYT:TIC2003-03783, UC3M:FAVICOBIS and CAM:FACTOTEM-CM (S-0505/ESP/000417).Publicad
Minimal formulation of the linear spatial analysis of capillary jets: Validity of the two-mode approach
A rigorous and complete formulation of the linear evolution of harmonically stimulated
capillary jets should include infinitely many spatial modes to account for arbitrary exit
conditions [J. Guerrero et al., J. Fluid Mech. 702, 354 (2012)]. However, it is not rare to
find works in which only the downstream capillary dominant mode, the sole unstable one,
is retained, with amplitude determined by the jet deformation at the exit. This procedure
constitutes an oversimplification, unable to handle a flow rate perturbation without jet
deformation at the exit (the most usual conditions). In spite of its decaying behavior, the
other capillary mode (subdominant) must be included in what can be called a “minimal
linear formulation.” Deformation and mean axial velocity amplitudes at the jet exit are the
two relevant parameters to simultaneously find the amplitudes of both capillary modes.
Only once these amplitudes are found, the calculation of the breakup length may be
eventually simplified by disregarding the subdominant mode. Simple recipes are provided
for predicting the breakup length, which are checked against our own numerical simulations.
The agreement is better than in previous attempts in the literature. Besides, the limits of
validity of the linear formulation are explored in terms of the exit velocity amplitude, the
wave number, the Weber number, and the Ohnesorge number. Including the subdominant
mode extends the range of amplitudes for which the linear model gives accurate predictions,
the criterion for keeping this mode being that the breakup time must be shorter than a
given formula. It has been generally assumed that the shortest intact length happens for the
stimulation frequency with the highest growth rate. However, we show that this correlation
is not strict because the amplitude of the dominant mode has a role in the breakup process
and it depends on the stimulation frequency.Ministerio de Economía, Industria y Competitividad, Spain, under Contract No. FIS2014-25161Junta de Andalucía under Contract No. P11-FQM-791
Novel tuneable filter based on MZ and an amplified ring resonator for OFDM networks
IEEE Lasers and Electro-Optics Society. 1999 Annual Meeting. 8-11 November 1999. San Francisco, CAA novel reconfigurable fibre based tuneable filter is proposed. The module relies on a cascaded connection of Mach-Zehnders and an amplified fibre ring resonator. MHz range adjustable FHWM bandwidths and high crosstalk are achieved.Publicad
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