M. C. Maccarone

Mathematical Morphology Based on Fuzzy Operators

A vision procedure may be considered as the repeated application of image operators until the vision goal is reached. The type of these operators and the spaces on which they are defined and act depends on the specific problem and on what we are searching on the image. Morphological operations, as filtering, edge detection, skeletonizing, and so on, are mainly required at low and medium levels of the vision procedure, where local and global knowledge is used to enhance the image information content, before a final decision about the image is taken.

Features selection and `possibility theory'

Abstract A method is presented that uses both ‘cluster analysis’ and ‘possibility theory’ to select the most significant variables in multidimensional data. The method is applied to a set of biomedical data from electron spin resonance spectroscopy measurements on patients with a brain injury.

Detection of 33.8 Millisecond X-Ray Pulsations in SAX J0635+0533

We revisited the BeppoSAX observation of SAX J0635+0533, which was suggested as a possible counterpart to the gamma-ray source 2EG J0635+0521. We have discovered a 33.8 ms pulsation from the source and derived an improved position, consistent with the location of the Be star proposed as a binary companion. We interpret the periodicity as the spin period of a neutron star in a binary system with a Be companion.

Fuzzy mathematical morphology to analyse astronomical images

Traditionally, astronomical data are represented by images. X- and gamma-ray telescopes have been designed in order to produce images in these ranges of energy. Data are characterized by low signal embedded in structured background. The paper introduces a new approach, based on fuzzy-morphology, to restore and retrieve structural properties of such images. Experimental results are shown on astronomical images in order to evaluate the methodologies introduced.<<ETX>>

PDB: a pictorial database oriented to data analysis

The paper describes a new pictorial database oriented to image analysis, implemented inside the MIDAS data analysis system. Pictorial databases need expressive data structures in order to represent a wide class of information from the numerical to the visual. The model of the database is relational; however, a full normalization is not achievable, owing to the complexity of the visual information. The paper reports the general design and notes on the software implementation. Preliminary experiments show the performance of the pictorial database.

An Approach to Random Images Analysis

The study of random images requires new approaches, as a matter of fact that their meaning is strongly dependent from the context of the research field and the classical techniques for shape analysis are not sufficient. Aim of the paper is the definition of an “open” knowledge based system for the analysis of problems dealing with such kind of image data.

The INAF ASTRI Project in the framework of CTA

The ASTRI project aims to develop, in the framework of the Cherenkov Telescope Array, an end-to-end prototype of the small-size telescope, devoted to the investigation of the energy range ~ 1-100 TeV. The proposed design is characterized by two challenging but innovative technological solutions which will be adopted for the first time on a Cherenkov telescope: a dual-mirror Schwarzschild-Couder configuration and a modular, light and compact camera based on Silicon photo-multipliers. Here we describe the prototype design, the expected performance and the possibility to realize a mini array composed by a few such telescopes, which shall be placed at the final CTA Southern Site.

The absolute calibration strategy of the ASTRI SST-2M telescope proposed for the Cherenkov Telescope Array and its external ground-based illumination system

ASTRI is the end-to-end prototype for the CTA small-size class of telescopes in a dual-mirror configuration (SST-2M) proposed by the Italian National Institute of Astrophysics (INAF) in the framework of the Cherenkov Telescope Array. ASTRI SST-2M has been installed at the Serra La Nave Astrophysical Observatory on Mount Etna (Sicily) and its Performance Verification Phase will start in autumn 2016. For the relative pixel calibration and gain monitoring, the ASTRI SST-2M camera is equipped with an internal illumination device, while an external, portable, illumination system, placed at a few km distance from the telescope, will be used for the absolute end-to-end calibration of the telescope spectral response. Moreover analysis of signals induced in the camera pixels by the night sky background (diffuse emission and reference stars) will be used to monitor the long term evolution of the telescope calibration. We present an overview of the ASTRI SST-2M absolute calibration strategy and the external illuminating device that will be used for its spectral calibration

Fusion of experimental data

Abstract The integration of information from various sensory systems is one of the most difficult challenges in understanding both perception and cognition. For example, the problem of auditory-visual integration is a correspondence problem between perceived auditory and visual scenes. Two main questions arise when designing data analysis systems: what is the useful information to be integrated?, and what are the integration rules? The problem of integrating information becomes relevant whenever: (a) the same kind of data are detected by spatially distributed sensors; (b) heterogeneous data are detected by different sensors; (c) heterogeneous distributed data are involved. General problems concerning the integration of experimental data are reviewed. The case of the BeppoSAX X-ray astronomical satellite is given as an example.

Suitability of a content-based retrieval method in astronomical image databases

Abstract Indexing and retrieval methods based on the image content are required to effectively use information from large repositories of digital images. Usually, the way to search for data and images in astronomical archives is via textual queries expressed in terms of constraints on observation parameters. In this paper we present a method for automatic extraction of images by using shape descriptions based on local symmetry. The proposed indexing methodology has been developed and tested inside JACOB, a prototypal system for content-based video database querying.