1,721,109 research outputs found
Promuovere le potenzialità degli studenti con DSA. Scuola secondaria e università a 10 anni dalla Legge 170
No full textStatistical modelling of spads for time-of-flight lidar
Full text linkTime-of-Flight (TOF) based Light Detection and Ranging (LiDAR) is a widespread technique for distance measurements in both single-spot depth ranging and 3D mapping. Single Photon Avalanche Diode (SPAD) detectors provide single-photon sensitivity and allow in-pixel integration of a Time-to-Digital Converter (TDC) to measure the TOF of single-photons. From the repetitive acquisition of photons returning from multiple laser shots, it is possible to accumulate a TOF histogram, so as to identify the laser pulse return from unwelcome ambient light and compute the desired distance information. In order to properly predict the TOF histogram distribution and design each component of the LiDAR system, from SPAD to TDC and histogram processing, we present a detailed statistical modelling of the acquisition chain and we show the perfect matching with Monte Carlo simulations in very different operating conditions and very high background levels. We take into consideration SPAD non-idealities such as hold-off time, afterpulsing, and crosstalk, and we show the heavy pile-up distortion in case of high background. Moreover, we also model non-idealities of timing electronics chain, namely, TDC dead-time, limited number of storage cells for TOF data, and TDC sharing. Eventually, we show how the exploit the modelling to reversely extract the original Li-DAR return signal from the distorted measured TOF data in different operating conditions
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“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
Inclusion & Beyond: facilitating academic success and job placement of university students with SLD
No full text60-channel High-resolution Counter Array For High-speed Continuous Long-term Data Acquisition
No full textAppropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
SISTEMA E METODO PER LA RIVELAZIONE, LOCALIZZAZIONE E SEGNALAZIONE DI EVENTI DI SINGOLO FOTONE E DI COINCIDENZA TEMPORALE DI ALMENO DUE FOTONI
No full textMulti-Channel SPAD Chip for Silicon Photonics with Multi-Photon CoIncidence Detection
Full text linkWe present the design and characterization of a microelectronic chip consisting of 32 independent single-photon counting and multi-photon time-coincidence channels, based on Single Photon Avalanche Diodes (SPADs). The chip aims at easing the assembly together with Silicon Photonics substrates and chips, for a broad spectrum of quantum applications. The chip provides not only 32 independent pulse outputs for multi-channel single-photon counting, but it features other two operation modalities. For single-photon applications, the chip provides the single-hit digital address of the channel detecting the photon among the 32 ones. For multi-photon applications, the chip provides an event-driven pulse every time more than n photons (n selectable between 2 and 4) concurrently trigger different channels. Each detection channel consists of 4 independent SPADs with different diameter (5 μm, 10 μm, 20 μm, and 50 μm), to easily match the waveguides and collection efficiency
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