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2003 Article Unknown

Preliminary results on the foraging ecology of Balearic shearwaters (Puffinus mauretanicus) from bird-borne data loggers
Aguilar J. S., Benvenuti S., Dall'Antonia L., Mcminn-grivè M., Mayol-serra J.
A data logger devised and manufactured by our research team in order to study the homing routes of carrier pigeons was subsequently modified to study the homing and foraging strategies of breeding marine birds. Recent versions of the data logger, equipped with a flight sensor and depth meter or saltwater switch, were used in a study of the foraging strategies of chick-rearing Balearic shearwaters (Puffinus mauretanicus) in the framework of the project LIFE-Puffinus financed by the Balearic Government amd the EU. Due to low recapture rates (only 3 out of 6 tagged birds were recovered), only preliminary data from a small sample are available. Data loggers have recorded data on the pattern of nest attendance (including departure time to foraging trips and return time) and the diurnal pattern of flight and dive activity (including depth and duration of dives). Despite the small sample size, the results show that our data loggers can successfully be applied to the study of the breeding biology and foraging ecology - including the diving pattern-of Balearic shearwaters and similar speciesSource: Scientia marina 67 (2003): 129–134.

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2003 Article Unknown

Skewed alpha-stable distributions for modelling textures
Kuruoglu E. E, Zerubia J.
In this letter, we introduce a novel family of texture models which provide alternatives to texture models which are based on Gaussian distributions. In particular, we introduce linear textures generated with a member of the alpha-stable distribution family which is a generalisation of the Gaussian distribution. The new family of texture models is capable of representing both impulsive and unsymmetric (skewed) image data which cannot be accommodated by the Gaussian model. We present new techniques for texture model estimation and we demonstrate the success of the techniques on synthetic data.Source: Pattern recognition letters 24 (2003): 339–348.

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2003 Article Unknown

SAR image denoising via Bayesian wavelet shrinkage based on heavy-tailed modeling
Achim A., Tsakalides P., Bezerianos A.
Synthetic aperture radar (SAR) images are inherently affected by multiplicative speckle noise, which is due to the coherent nature of the scattering phenomenon. This paper proposes a novel Bayesian-based algorithm within the framework of wavelet analysis, which reduces speckle in SAR images while preserving the structural features and textural information of the scene. First, we show that the subband decompositions of logarithmically transformed SAR images are accurately modeled by alpha-stable distributions, a family of heavy-tailed densities. Consequently, we exploit this a priori information by designing a maximum a posteriori (MAP) estimator. We use the alpha-stable model to develop a blind speckle-suppression processor that performs a non-linear operation on the data and we relate this non-linearity to the degree of non-Gaussianity of the data. Finally, we compare our proposed method to current state-of-the-art soft thresholding techniques applied on real SAR imagery and we quantify the achieved performance improvement.Source: IEEE transactions on geoscience and remote sensing 41 (2003): 1773–1784.

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2003 Article Unknown

Source separation in astrophysical maps using independent factor analysis
Kuruoglu E. E., Bedini L., Paratore M. T., Salerno E., Tonazzini A.
A microwave sky map results from a combination of signals from various astrophysical sources, such as cosmic microwave background radiation, synchrotron radiation and galactic dust radiation. To derive information about these sources, one needs to separate them from the measured maps on different frequency channels. Our insufficient knowledge of the weights to be given to the individual signals at different frequencies makes this a difficult task. Recent work on the problem led to only limited success due to ignoring the noise and to the lack of a suitable statistical model for the sources. In this paper, we derive the statistical distribution of some source realizations, and check the appropriateness of a Gaussian mixture model for them. A source separation technique, namely, independent factor analysis, has been suggested recently in the literature for Gaussian mixture sources in the presence of noise. This technique employs a three layered neural network architecture which allows a simple, hierarchical treatment of the problem. We modify the algorithm proposed in the literature to accommodate for space-varying noise and test its performance on simulated astrophysical maps. We also compare the performances of an expectation-maximization and a simulated annealing learning algorithm in estimating the mixture matrix and the source model parameters. The problem with expectation-maximization is that it does not ensure global optimization, and thus the choice of the starting point is a critical task. Indeed, we did not succeed to reach good solutions for random initializations of the algorithm. Conversely, our experiments with simulated annealing yielded initialization-independent results. The mixing matrix and the means and coefficients in the source model were estimated with a good accuracy while some of the variances of the components in the mixture model were not estimated satisfactorily.Source: Neural networks 16 (2003): 479–491.

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2003 Article Unknown

Reversal of visual impairment in patients with retinis pigmentosa after administration of glutathione peroxidase enzyme
Ammannati P., Giordani R., Chimenti M.
The glutathione peroxidase enzyme (GPX) administration effects have been studied in patients with retinitis pigmentosa (RP). RP at present is defined as a degenerative, progressive and irreversible one. It was found that in RP patients there was a decrease of GPX level in respect to normal subjects. Moreover in rabbits it was shown that retrobulbar administration of GPX prevents the abolition of the electroretinogram due to previous administration of an oxidant agent as AgNO. On the basis of the results obtained, it was hypothesized that a deficit of reducing enzyme of the pentose phosphate pathway may binder the regeneration of the pigment modified by the oxidation process due to light that hits the retina. This process can bring to a pathological increase of the epithelial pigmentation. It was decided to investigate the potential effect of the replacement therapy with GPX administration. The number of patients is 7636 and their cumulative data are reported. The treatment was administration of one I.U. of GPX in retrobulbar fat, for three consecutive days each month, for three consecutive months, in each eye. We measured the visual acuity, the peripheral retinal fields and ERG before and after therapy. After completion of therapy over the 90% of the patients showed a significant clinical improvement, confirmed by the measured parameters. The amelioration for visual acuity ranged from 1/10 (R.E.) to no variation (L.E.) to 68% in both eyes. ERG, extinct in about 98% the patients, presented an improvement from a normal morphology with a very reduced voltage to a normal voltage and morphology. These results have been stable for the 6 years of follow-up. The results support the hypothesis that a deficit of GPX may play an important role in the pathophysiology of RP. These results conduct to consider that the pentose phosphate pathway is essential for the retina correct metabolism and function.Source: Atti della Fondazione "Giorgio Ronchi" 2 (2003): 187–195.

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2003 Article Unknown

Una Stella nel Battistero di Pisa
Tarabella L.
A computer analysis on the reverberation characteristics of Pisa Baptistery and the studies about the symmetries of the Monuments of the whole Piazza dei Miracoli in Pisa by the american mathematician David Speiser, led to the discovery of a suggestive reference frame used for designing and building the Baptistery: everthing here is based on the golden number, the regular pentagon and, finally, a star.Source: Ricerca e Futuro (2003): 29–32.

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2003 Article Unknown

Quando l'astrofisica chiede aiuto all'informatica. L'analisi dei dati astrofisici ha bisogno della ricerca informatica più avanzata
Salerno E.
L'elaborazione statistica dei segnali sia avvia ad assumere un ruolo chiave nello studio del nostro Universo. Molti problemi dell'astrofisica sono infatti legati alla possibilità di discriminare tra teorie in competizione nell'affascinante impresa di comprenderne la nascita, l'evoluzione e il destino, e un loro aspetto comune è che l'informazione utile si deve estrarre da insiemi di dati di dimensione enorme e affetti da notevoli errori. Dal punto di vista informatico si tratta di 'data mining', ossia di ricerca di informazione nascosta. Un caso in cui oggi si deve ricorrere a tecniche di data mining è rappresentato dallo studio della radiazione cosmica di fondo.Source: Ricerca e Futuro 21 (2003): 21–22.

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2003 Conference object Unknown

Pozitif alfa-kararli olasilik yogunluk fonksiyonu icin analitik bir yaklastirma
Kuruoglu E. E.
Bu makelede, genelde analitik bir ifadeye sahip olmayan pozitif alpha-kararli olasilik yogunluk fonksiyonu icin analitik bir yaklastirma 'oneriyoruz. 'Onerdigimiz yaklastirma, pozitif alpha-kararli rastsal degiskenlerin Pearson ve diger bir pozitif alpha-kararli dagilima c'oz'umlenmesine dayanmakta. Bu c'oz'umleme herhangi bir pozitif alpha-kararli dagilimin birer Pearson karisimi seklinde ifade edilebilmesini saglamakta.Source: Sinyal Isleme ve Iletisim Uygulamalari Kurultayi, SIU'03 (Turkish National Signal Processing Conference), Istanbul, 18-20 June 2003

See at: siu2003.eng.ku.edu.tr | CNR People


2003 Conference object Unknown

The OBJECT-ORIENTED pureCMusic FRAMEWORK
Tarabella L.
The Object-Oriented pureCMusic (OO-pCM) framework gives the possibility to write a piece of music in terms of an algorithmic-composition-based program (also controlled by data streaming from external controllers) and of synthesis algorithms. Everything is written following the C language syntax and compiled into machine code that runs at CPU speed. The framework provides a number of functions for sound processing, for generating complex events and for managing external data coming from standard Midi controllers and/or other special gesture interfaces.Source: Understanding and Creating Music, N.3, Caserta, 1-11 December 2003

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2003 Conference object Unknown

The pCM framework for realtime sound and music generation
Tarabella L.
This programming framework gives the possibility to write a piece of music in terms of synthesis algorithms, score and management of data streaming from external interfaces. The pCM framework falls into the category of the 'embedded music language' and has been implemented under the Metrowerks' Code Warrior C-compiler. I started to write a very basic library of functions for sound processing and for driving the gesture interfaces realized at cART project of CNR, Pisa. In the long run the library became a very efficient, stable and powerful framework based on pure C programming, that is 'pure-C-Music', or pCM.Source: XIV Colloquium on Musical Informatics (XIV CIM 2003), N.14, pp. 145–149, Florence, 8-9-10 May 2003

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2003 Conference object Unknown

Özilintili imgelerin markoff rastgele alanlari yardimi ile ayristirilmasi
Tonazzini A., Bedini L., Kuruoglu E. E., Salerno E.
Bu makalede g'ur'ult'ul'u imgelerin bau gi msi z bilec senlerine ayri lmasi problemini c c'ozmeyi amac cli yor. Kaynak ayri c sti rma problemini bau gi msi z bilec sen ayri c sti rma yaklac si mi c cerc cevesinde ele alarak bir Bayes kestirim algoritmasi gelic stiriyoruz. Bu teknik ile Bayes formulasyonunun 'onsel bilgiyi kullanma yetisinden imgelerdeki 'ozilintiyi modellemede ve ayri c sti rma ic slemine dahil etmekte yararlani lmaktadi r. Bir enc cok sonsal (MAP) kestirim tekniu gi ve hem kari c si m matrisini hem kaynaklari kestiren tavlama benzetimine dayanan bir algoritma 'oneriyoruz. c Cec sitli yapay ve gerc cek imgelerle yapti gu i mi z deneyler, 'ozilintileri hesaba katan bir kaynak modelinin g'ur'ult'uye karc si dayani kli li u gi artti rdi u gi ni g'osteriyor.Source: Sinyal Isleme ve Uygulamalari Kurultayi, SIU 2003 (Turkish Signal Processing Conference), Istanbul, 18-20 Giugno 2003

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2003 Conference object Unknown

An innovative telemedicine platform of services for healthcare provision in restrictive and closed environments
Di Bona S, La Manna R, Fontanelli R
In this paper we present the HUMAN (Health throUgh teleMAtics for Inmates) Project that aims to develop an innovative umbrella of health services in detention environments in order to improve the inmates' healthcare provision and to provide an efficient, effective and secure support to the everyday activity of the medical staff. A Web-enabled Decision support system has been designed in order to overcome the problems related to the large amount of clinical data to be managed for each inmate, which usually implies an inadequate and discontinuous healthcare provision. The decision support system has been integrated with smart environments (prison cells), tailored on the health requirements of inmates with special needs, such as disabled or elderly persons. Furthermore interoperability and security aspects have been accurately analysed and faced. The first results obtained show the positive impact of these ICT services for the Prison environment and the entire society and the effectiveness of the approach proposed. The modules developed are implemented for validation in two European detention structures.Source: International Conference on Politics and Information Systems: Technologies and applications (PISTA'03), pp. 313–318, Orlando, 31 July - 2 August 2003

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2003 Conference object Unknown

Analytical representation for positive alpha-stable densities
Kuruoglu E. E.
In this paper, we present an analytical approximation to positive a-stable probability distribution functions, which in general do not possess a compact analytical form. Our approximation is based on decomposing a positive a-stable random variable into a product of a Pearson and another positive stable random variable. This decomposition allows one to approximate any positive stable pdf as a mixture of Pearson densities, hence providing an analytical representation. This representation allows one to employ maximum likelihood estimation and Bayesian techniques in the presence of positive a-stable noise or signals. The efficiency of the decomposition is demonstrated by simulation studies.Source: International Conference on Acoustics, Speech, and Signal Processing, 2003 - ICASSP'03, pp. 729–732, Hong Kong, 6-10 April 2003

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2003 Conference object Unknown

Blind separation of auto-correlated images from noisy mixtures using MRF models
Tonazzini A., Bedini L., Kuruoglu E., Salerno E.
This paper deals with the blind separation and reconstruction of source images from mixtures with unknown coefficients, in presence of noise. We address the blind source separation problem within the ICA approach, i.e. assuming the statistical independence of the sources, and reformulate it in a Bayesian estimation framework. In this way, the flexibility of the Bayesian formulation in accounting for prior knowledge can be exploited to describe correlation within the individual source images, through the use of suitable Gibbs priors. We propose a MAP estimation method and derive a general algorithm for recovering both the mixing matrix and the sources, based on alternating maximization within a simulated annealing scheme. We experimented with this scheme on both synthetic and real images, and found that a source model accounting for correlation is able to increase robustness against noise.Source: 4th International Symposium on Independent Component Analysis and Blind Signal Separation (ICA 2003), pp. 675–680, Nara, Japan, 1-4 April 2003

See at: CNR People | www.kecl.ntt.co.jp


2003 Part of book or chapter of book Unknown

Interazione e Gestualità
Tarabella L.
The term 'interaction' has been introduced in the computer music community for labeling the new approach for making electro-acoustic music in respect to the classic off-line post-production approach to compose. However, in the wider world of contemporary art which makes use of technology, 'interactivity' is commonly used and more popular for what concerns multimedia installations. The meaning is toward the interaction between people from public and the installation itself rather than between the artist/performer and a computer system. So, in order to avoid misunderstandings that often arise, the ' gesturally-controlled real-time interactive computer music' or more simply 'gesture controlled performance' has been introduced. Interactive electro-acoustic music proposes a complete new scenario not even for the new sound palettes introduced but, rather, for the new kind of relationships experienced by the audience between what-is-going-on-on-stage and the final musical result.Source: edited by Vassallo S.; Di Brino A.. Pisa: ETS, 2003

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2003 Other Unknown

Applications of independent component analysis in communications, image processing and geophysics
Kuruoglu E. E., Sankur B.
The project aims at unifiying the expertise of researchers in ISTI-CNR, Bogazici University, Izmir Institute of Technology and Istanbul Technical University on source separation techniques and exchange expertise for application in areas such as image separation, face recognition, geophysical signal separation, biomedical signal processing, telecommunications, astrophysics, textile engineering, etc. The application areas that are explored are vast and we aim to develop a unifying framework of techniques effective for all areas.

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2003 Other Unknown

An identification system of musical tones
Bertini G., Di Salvo V. G.
The aim of this paper is to present a system for the automatic identification of musical tones from a monophonic music melody in progress, among available alternatives of a library of the same previously recorded tones. This study was born by the demand to have a tool based on a comparison criterion to measure the fidelity of reproduction of some musical tones during a musical piece in execution. The algorithm is realized in two main distinct steps. At first, digital processing techniques are used with the purpose to obtain a pattern vectors from the original waveform. Thanks to the analysis techniques of Short-Time Fourier Transform, it has been possible to extract these patterns, so that they could to reflect precise energy-dependent features of the original signal, relevant to the identification. This resulting patterns are, subsequently, elaborated using the Theory of the Least Squares Optimal Filtering. The Least Squares Criterion is, here, regarded as purely deterministic, that is there is no presumed knowledge of the statistical properties. Therefore the algorithm has several desirable features. There is no upper limit on the frequency search range, so the algorithm is suited for high-pitched tones. The algorithm is relatively simple and may be implemented efficiently and with low latency on DSP processors. A preliminary investigation of the problem was developed in cooperation between the Norwegian University of Science and Technology of Trondheim and the National Research Council of Pisa, in Italy, in the framework of a stage at NTNU within the European Project 'Mosart' (2003).

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2003 Other Unknown

Application of minimum coherence criterion for blind source separation
Ballatore P., Bedini L.
The Blind Source Separation (BSS) is performed using multiple observations of mixtures of dependent or independent astrophysical sources of diffuse microwave radiation. Two separation methods are used and compared: (a)FastICA, which are already been used for similar astrophysical data, (b) the minimum coherence criterion. Results show that both methods give better results in the case of independence aming the sources that in the case of dependence. In particular, in the case of the data sets considered, method (b) (newly applied to similar astrophysical data) generally gives better source estimates than method (a), especially in the case of correlated sources, where FastICA is not optimal because of its assumption of orthogonality among the sources.

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2003 Other Unknown

CSS - Cascading Style Sheets
Martinelli M.
Introduzione a CSS

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2003 Other Unknown

IFATEST v.0.0: manuale del programmatore
Salerno E.
IFATEST è un codice in Fortran 90 per la sperimentazione di un algoritmo di analisi ai fattori indipendenti (IFA) ispirato a quello presentato da Attias in [1]. Lo scopo di questo algoritmo è quello della separazione cieca di segnali ottenuti da misture istantanee rumorose di sorgenti indipendenti. La variante qui proposta [2] prevede l'uso di una strategia di annealing simulato piuttosto che l'algoritmo Expectation-Maximization proposto da Attias per l'apprendimento del modello dati. I potenziali vantaggi di questa strategia consistono nell'indipendenza della soluzione dalla stima iniziale e in una maggiore robustezza nei confronti del rumore. I primi risultati ottenuti [2] vanno verso una conferma di queste aspettative. Un altro sicuro vantaggio dell'annealing simulato sull'approccio di Attias è che le eventuali informazioni a priori su alcuni dei parametri incogniti del problema possono essere inserite facilmente nella strategia di ottimizzazione. In questa prima stesura del codice non è sfruttata la possibilità di trattare rumore non stazionario, che, in base ad opportune approssimazioni, può essere un vantaggio dell'approccio IFA sugli algoritmi proposti in precedenza per la separazione cieca di sorgenti [2, 3]. Il codice qui presentato non ha limitazioni sul numero massimo di sorgenti e canali di misura da trattare (salvo, ovviamente, limitazioni di memoria e di tempo di elaborazione) e consente di variare con estrema facilità i parametri del modello che devono venire considerati incogniti, i valori dei parametri da considerare noti e la stima iniziale della soluzione. Anche lo schema di annealing può essere facilmente modificato.

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