fondazione bruno kessler

About: fondazione bruno kessler is a facility organization based out in Trento, Italy. It is known for research contribution in the topics: Silicon photomultiplier & Detector. The organization has 1145 authors who have published 4730 publications receiving 94404 citations. The organization is also known as: Trentino Institute of Culture.

Development and Alignment of a Domain-Specific Ontology for Question Answering

Abstract: With the appearance of Semantic Web technologies, it becomes possible to develop novel, sophisticated question answering systems, where ontologies are usually used as the core knowledge component. In the EU-funded project, QALL-ME, a domain-specific ontology was developed and applied for question answering in the domain of tourism, along with the assistance of two upper ontologies for concept expansion and reasoning. This paper focuses on the development of the QALL-ME ontology in the tourism domain and its alignment with the upper ontologies - WordNet and SUMO. The design of the ontology is presented in the paper, and a semi-automatic alignment procedure is described with some alignment results given as well. Furthermore, the aligned ontology was used to semantically annotate original data obtained from the tourism web sites and natural language questions. The storage schema of the annotated data and the data access method for retrieving answers from the annotated data are also reported in the paper.

Compact SPAD-Based Pixel Architectures for Time-Resolved Image Sensors

Abstract: This paper reviews the state of the art of single-photon avalanche diode (SPAD) image sensors for time-resolved imaging. The focus of the paper is on pixel architectures featuring small pixel size ( 20%) as a key enabling technology for the successful implementation of high spatial resolution SPAD-based image sensors. A summary of the main CMOS SPAD implementations, their characteristics and integration challenges, is provided from the perspective of targeting large pixel arrays, where one of the key drivers is the spatial uniformity. The main analog techniques aimed at time-gated photon counting and photon timestamping suitable for compact and low-power pixels are critically discussed. The main features of these solutions are the adoption of analog counting techniques and time-to-analog conversion, in NMOS-only pixels. Reliable quantum-limited single-photon counting, self-referenced analog-to-digital conversion, time gating down to 0.75 ns and timestamping with 368 ps jitter are achieved.

Classification of hyperspectral data using extended attribute profiles based on supervised and unsupervised feature extraction techniques

Abstract: The classification of remote sensing data based on the exploitation of spatial features extracted with morphological and attribute profiles has been recently gaining importance. With the development of efficient algorithms to construct the profiles for large datasets, such methods are becoming even more relevant. When dealing with hyperspectral imagery, the profiles are traditionally built on the first few principal components computed from the data. However, it needs to be determined if other feature reduction approaches are better suited to create base images for the profiles. In this article, we explore the use of profiles based on features derived from three supervised feature extraction techniques (i.e. Discriminant Analysis Feature Extraction, Decision Boundary Feature Extraction and Non-parametric Weighted Feature Extraction) and two unsupervised feature-extraction techniques (i.e. Principal Component Analysis (PCA) and Kernel PCA) in classification and compare the classification accuracies obtaine...

Comparison Between Different Sound Source Localization Techniques Based on a Real Data Collection

Abstract: Comparing the different sound source localization techniques, proposed in the literature during the last decade, represents a relevant topic in order to establish advantages and disadvantages of a given approach in a real-time implementation. Traditionally, algorithms for sound source localization rely on an estimation of time difference of arrival (TDOA) at microphone pairs through GCC-PHAT When several microphone pairs are available the source position can be estimated as the point in space that best fits the set of TDOA measurements by applying global coherence field (GCF), also known as SRP-PHAT, or oriented global coherence field (OGCF). A first interesting analysis compares the performance of GCF and OGCF to a suboptimal LS search method. In a second step, Adaptive Eigenvalue Decomposition is implemented as an alternative to GCC-PHAT in TDOA estimation. Comparative experiments are conducted on signals acquired by a linear array during WOZ experiments in an interactive-TV scenario. Changes in performance according to different SNR levels are reported.

CGC factorization for forward particle production in proton-nucleus collisions at next-to-leading order

Abstract: Within the Color Glass Condensate effective theory, we reconsider the next-to-leading order (NLO) calculation of the single inclusive particle production at forward rapidities in proton-nucleus collisions at high energy. Focusing on quark production for definiteness, we establish a new factorization scheme, perturbatively correct through NLO, in which there is no ‘rapidity subtraction’. That is, the NLO correction to the impact factor is not explicitly separated from the high-energy evolution. Our construction exploits the skeleton structure of the (NLO) Balitsky-Kovchegov equation, in which the first step of the evolution is explicitly singled out. The NLO impact factor is included by computing this first emission with the exact kinematics for the emitted gluon, rather than by using the eikonal approximation. This particular calculation has already been presented in the literature [1, 2], but the reorganization of the perturbation theory that we propose is new. As compared to the proposal in [1, 2], our scheme is free of the fine-tuning inherent in the rapidity subtraction, which might be the origin of the negativity of the NLO cross-section observed in previous studies.