86,513 research outputs found
Emerging Applications of Whispering Gallery Mode Photonic Resonators
No full textWhispering Gallery Mode photonic resonators are emerging as key building blocks in many application fields especially because their resonant frequency is very sensitive to the variation of any physical or geometrical parameter. The basic properties and the applications of these resonators are discussed in this paper, with a specific attention to three very important application fields, i.e. Space, health-care, and environment monitoring
System test of a new optoelectronic gyro based on an InP ring resonator with a Q factor of one million
No full textExperimental countermeasures to reduce the backscattering noise in an InP hybrid optical gyroscope
No full textMiniaturization of the currently available medium- and high-performance angular velocity sensors is crucial for aerospace and defense industry. To face this technological challenge, we are investigating a new gyro, called gyroscope-on-chip (GoC), based on the InP photonic integrated circuits technology. The sensor we refer includes a passive ring resonator with a Q greater than one million and several optical/optoelectronic components all monolithically integrated on a single InP chip. Recent progress on the demonstration of the GoC is reported in this paper. In particular, the configuration of the readout circuit and the countermeasures against the backscattering noise are discussed
Reconfigurable optical beamformer with graphene-based fine-tunable optical delay line
No full textAn integrated graphene-based fine-tunable optical delay line in silicon nitride has been designed. A high optical delay time up to 920 ps has been calculated with a device footprint A ~ 4 mm2. The device includes two graphene-based Mach-Zehnder interferometer (MZI) switches and two vertically-stacked microring resonators. Graphene capacitors have been integrated in the optical delay line to exploit the electro-optic effect aiming at fast tuning (response time of few nanoseconds) with a low power dissipation. Such performance, together with optical loss α < 27 dB, makes this device suitable for beam-steering up to 20 radiating elements, with an angle of ±20° in the azimuth direction, of a tile in a phased-array antenna included in an X-band SAR
Impiantistica frigorifera innovativa con fluidi frigorigeni naturali
No full textNella seguente nota vengono esposte le linee programmatiche del progetto nazionale di ricerca sulle
“Tecnologie innovative sulla frigoconservazione con fluidi refrigeranti naturali”e l’attività finora
svolta dalle unità operative afferenti al progetto. Pertanto, dopo una sintetica introduzione sugli
effetti prodotti dall’emissione di fluidi refrigeranti sull’ambiente, sono stati riepilogati i regolamenti
emessi dagli accordi internazionali stipulati fra i vari Stati ed i limiti imposti dalla legislazione
europea sull’uso dei gas fluorurati.
Il progetto di ricerca ha previsto la costruzione ed il monitoraggio di tre impianti frigoriferi pilota
che utilizzano i due gas naturali di maggiore interesse e cioè l’anidride carbonica e l’aria.
Sono stati, quindi, esposti i criteri generali di progettazione degli impianti e la loro definizione
costruttiva, nonché le metodiche con cui si ritiene di valutarne l’efficienz
System test of an optoelectronic gyroscope based on a high Q-factor InP ring resonator
No full textThe experimental results of the system test of an optical resonant passive gyroscope based on a high Q-factor ring resonator in InP technology are reported. The open loop configuration based on the phase modulation was preferred among the analyzed configuration options, especially because it is potentially suitable for the monolithic integration of the entire sensor on a single chip. The setup components are described with a special emphasis on a custom digital readout board based on a field-programmable gate array. The board processes the input signals according to the proportional-integral algorithm which has been implemented through an optimized firmware. For the system test, the sensor rotation has been simulated using two properly driven acousto-optic modulators. The results reported here prove the gyro functionality and are a good starting point for the full development of the sensor
Rigorous design of an ultra-high Q/V photonic/plasmonic cavity to be used in biosensing applications
No full textA hybrid device based on a 1D PhC dielectric cavity vertically coupled to a plasmonic slot is proposed for use in biosensing applications. Under efficient coupling conditions between the Bloch mode in the 1D PhC dielectric cavity and the surface plasmon polaritons mode in the metal slot, an ultra-high Q/V ratio (similar to 10(7)(lambda/n)(-3)) has been achieved with a remarkable resonance transmission T (=47%), due to high spectral and spatial confinement in the cavity. The rigorous design process of the cavity, including the influence of geometrical and physical parameters on its performance, has been carried out using the 3D Finite Element Method. A strong light-matter interaction was observed, making the photonic-plasmonic cavity suitable for biosensing and, in particular, for optical trapping of living matter at nanoscale, such as proteins and DNA sections, as required in several biomedical applications. (C) 2015 Elsevier Ltd. All rights reserved
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
No full textNewspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
Also By The Same Author: AKTiveAuthor, a Citation Graph Approach to Name Disambiguation
No full textThe desire for definitive data and the semantic web drive for inference over heterogeneous data sources requires co-reference resolution to be performed on those data. In particular, name disambiguation is required to allow accurate publication lists, citation counts and impact measures to be determined. This paper describes a graph-based approach to author disambiguation on large-scale citation networks. Using self-citation, co-authorship and document source analyses, AKTiveAuthor clusters papers, achieving precision of 0.997 and recall of 0.818 over a test group of eight surname clusters
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