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2017 Article Unknown

Variance analysis of unbiased complex-valued lp-norm minimizer
Chen Y., So H. C., Kuruoglu E. E., Yang X. L.
Parameter estimation from noisy complex-valued measurements is a significant topic in various areas of science and engineering. In this aspect, an important goal is finding an unbiased estimator with minimum variance. Therefore, variance analysis of an estimator is desirable and of practical interest. In this paper, we concentrate on analyzing the complex-valued â,,"p-norm minimizer with pâ?¥1. Variance formulas for the resultant nonlinear estimators in the presence of three representative bivariate noise distributions, namely, α-stable, Student's t and mixture of generalized Gaussian models, are derived. To guarantee attaining the minimum variance for each noise process, optimum selection of p is studied, in the case of known noise statistics, such as probability density function and corresponding density parameters. All our results are confirmed by simulations and are compared with the Cramér-Rao lower bound.Source: Signal processing (Print) (2017): 17–25. doi:10.1016/j.sigpro.2016.12.018
DOI: 10.1016/j.sigpro.2016.12.018

See at: DOI Resolver | CNR People | www.sciencedirect.com


2017 Article Open Access OPEN

The information capacity of the genetic code: is the natural code optimal?
Kuruoglu E. E, Arndt P. F.
We envision the molecular evolution process as an information transfer process and provide a quantitative measure for information preservation in terms of the channel capacity according to the channel coding theorem of Shannon. We calculate Information capacities of DNA on the nucleotide (for non-coding DNA) and amino acid (for coding DNA) level using various substitution models. We extend our results on coding DNA to a discussion about the optimality of the natural codon-amino acid code. We provide the results of an adaptive search algorithm in the code domain and demonstrate the existence of a large number of genetic codes with higher information capacity. Our results support the hypothesis of an ancient extension from a 2-nucleotide codon to the current 3-nucleotide codon code to encode the various amino acids.Source: Journal of theoretical biology 419 (2017): 227–237. doi:10.1016/j.jtbi.2017.01.046
DOI: 10.1016/j.jtbi.2017.01.046

See at: MPG.PuRe Open Access | MPG.PuRe Open Access | DOI Resolver | CNR People | www.sciencedirect.com


2017 Article Unknown

Advanced infrared technology and applications 2015
Moroni D., Raimondi V, Sakagami T.
Source: Measurement science & technology (Print) 28 (2017). doi:10.1088/1361-6501/aa59be
DOI: 10.1088/1361-6501/aa59be

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2017 Report Unknown

SEMEOTICONS - Model final tuning
Colantonio S., Coppini G., Zuccalà C. V.
In this document, we outline the advisable actions to be taken into account for further development of the Wize Mirror. In particular, it emerged that some technological improvement of data acquisition procedures might be useful to enhance the Wize Mirror usage in a general setting such as at home. As far as the semantic integration performed by the Virtual Individual Model (VIM), no specific adjustment seems advisable at present. In fact, the VIM and the Wellness Index (WI) were able to describe the user status coherently with clinical and psychological characterisation of the volunteers enrolled in validation campaign.Source: SEMEOTICONS - Deliverable D6.4, 2017, 2017
Project(s): SEMEOTICONS via OpenAIRE

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2017 Article Unknown

Lip segmentation based on Lambertian shadings and morphological operators for hyper-spectral images
Danielis A., Giorgi D., Larsson M., Stromberg T., Colantonio S., Salvetti O.
Lip segmentation is a non-trivial task because the colour difference between the lip and the skin regions maybe not so noticeable sometimes. We propose an automatic lip segmentation technique for hyper-spectral images from an imaging prototype with medical applications. Contrarily to many other existing lip segmentation methods, we do not use colour space transformations to localise the lip area. As input image, we use for the first time a parametric blood concentration map computed by using narrow spectral bands. Our method mainly consists of three phases: (i) for each subject generate a subset of face images enhanced by different simulated Lambertian illuminations, then (ii) perform lip segmentation on each enhanced image by using constrained morphological operations, and finally (iii) extract features from Fourier-based modeled lip boundaries for selecting the lip candidate. Experiments for testing our approach are performed under controlled conditions on volunteers and on a public hyper-spectral dataset. Results show the effectiveness of the algorithm against low spectral range, moustache, and noise.Source: Pattern recognition 63 (2017): 355–370. doi:10.1016/j.patcog.2016.10.007
DOI: 10.1016/j.patcog.2016.10.007
Project(s): SEMEOTICONS via OpenAIRE

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2017 Article Unknown

The SENSEable Pisa project: citizen-participation in monitoring acoustic climate of Mediterranean city centres
Vinci B., Tonacci A., Caudai C., De Rosa P., Nencini L., Pratali L.
The concept of urban sustainability and liveability closely depends on multi-level approaches to environmental issues. The ultimate goal in the field of noise management is to involve citizens and facilitate their participation in urban environmental decisions. The SENSEable Pisa project, based on the concept of Real-Time City and Smart City, presents an acoustic urban monitoring system based on a low-cost data acquisition method for a pervasive outdoor noise measurement. The system is based on the use of noise sensors located on private houses in the centre of Pisa, which provide a good model for the current acoustic climate of Mediterranean city centres. In this study, SENSEable acquisitions show a strong anthropogenic component not revealed by public strategic maps. The anthropogenic component, commonly known as movida, becomes increasingly critical in Mediterranean cities, therefore, it is necessary to explore methods highlighting this new source and to adopt strategies for the creation of reliable noise pollution maps.Source: Clean (Weinh., Internet) (2017). doi:10.1002/clen.201600137
DOI: 10.1002/clen.201600137

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2017 Article Open Access OPEN

Bayesian Volterra system identification using reversible jump MCMC algorithm
Karakus O., Kuruoglu E. E., Altinkaya M. A.
Volterra systems have had significant success in modelling nonlinear systems in various real-world applications. However, it is generally assumed that the nonlinearity degree of the system is known beforehand. In this paper, we contribute to the literature on Volterra system identification (VSI) with a numerical Bayesian approach which identifies model coefficients and the nonlinearity degree concurrently. Although this numerical Bayesian method, namely reversible jump Markov chain Monte Carlo (RJMCMC) algorithm has been used with success in various model selection problems, our use is in a novel context in the sense that both memory size and nonlinearity degree are estimated. The aforementioned study ensures an anomalous approach to RJMCMC and provides a new understanding on its flexible use which enables trans-structural transitions between different classes of models in addition to transdimensional transitions for which it is classically used. We study the performance of the method on synthetically generated data including OFDM communications over a nonlinear channel.Source: Signal processing (Print) 141 (2017): 125–136. doi:10.1016/j.sigpro.2017.05.031
DOI: 10.1016/j.sigpro.2017.05.031

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2017 Article Unknown

Algae through the looking glass
Coltelli P., Barsanti L., Evangelista V., Gualtieri P.
Microalgae are one of the most suitable subjects for testing the potentiality of light microscopy and image analysis, because of the size of single cells, their endogenous chromaticity, and their metabolic and physiological characteristics. Microscope observations and image analysis can use microalgal cells from lab cultures or collected from water bodies as model to investigate metabolic processes, behavior/reaction of cells under chemical or photic stimuli, and dynamics of population in the natural environment in response to changing conditions. In this paper we will describe the original microscope we set up together with the image processing techniques we improved to deal with these topics. Our system detects and recognizes in-focus cells, extracts their features, measures cell concentration in multi-algal samples, reconstructs swimming cell tracks, monitors metabolic processes, and measure absorption and fluorescent spectra of subcellular compartments. It can be used as digital microscopy station for algal cell biology and behavioral studies, and field analysis applications.Source: Microscopy research and technique (Print) 80 (2017): 486–494. doi:10.1002/jemt.22820
DOI: 10.1002/jemt.22820

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2017 Article Open Access OPEN

Envisat RA-2 individual echoes: a unique dataset for a better understanding of inland water altimetry potentialities
Abileah R., Scozzari A., Vignudelli S.
The exploitation of synthetic aperture properties in nadir-looking radars is opening new scenarios in the framework of satellite radar altimetry. Both recent and upcoming missions including Cryosat-2, Sentinel-3, Sentinel-6 and SWOT take benefit from the coherent processing of radar data, aimed at improving range measurements in particular contexts, such as ice, open ocean, coastal zone, and even inland waters. This work investigates the possibilities offered by current and future satellite radar altimetry missions for the study of inland water bodies, probing into the peculiarities of the expected radar returns and their potential usage. In this regard, signals collected by the RA-2 instrument (Radar Altimeter 2) onboard the Envisat mission offer an unprecedented possibility, even with a relatively low pulse repetition frequency, to analyze the peculiarities of actual signals for detecting and ranging small water surfaces. In particular, the RA-2 instrument offers a global archive of Individual Echoes (IEs), collected at the native sampling rate of 1795 Hz, in addition to the 18 Hz data obtained by incoherent averaging, which are typically delivered to the users as standard products. RA-2 shares with future radar platforms such as Sentinel-6 a continuous and interleaved working modality, as was recommended by the scientific community in designing next missions' requirements. This is a further reason to consider the usage of RA-2 IEs as particularly attractive. Whilst only available for a small percentage of the earth's surface, sufficient IE data exist to study the height retrieval capability of these echoes, in particular for what concerns small water bodies, where we show that enough coherence is exhibited for focusing relatively narrow surfaces and range them correctly. A peculiar aspect of this work lies in the assumption that most of the returned echoes (in RA-2 IEs) are specular. A theoretical framework is developed according to this assumption, which is validated by investigating real RA-2 data and observing their related specular features. In particular, we discuss how specular echoes are expected to be very common in inland altimetry, and are most often associated with small to medium size lakes and rivers. This paper illustrates the expected electromagnetic behavior of specular water targets by exploiting the classical radar cross-section (RCS) theory for specular surfaces. Results from the model are compared with real IE data in three selected case studies, regarding two rivers of variable width and one flood plain, in order to check different hydrological regimes. The model very closely matches the data in all cases, making the results of this validation activity very promising. In particular, we demonstrate the feasibility of using satellite radar altimetry in rivers much smaller than what was considered possible until nowSource: Remote sensing (Basel) 9 (2017): 605. doi:10.3390/rs9060605
DOI: 10.3390/rs9060605

See at: Remote Sensing Open Access | Remote Sensing Open Access | DOI Resolver | CNR People | www.mdpi.com


2017 Report Unknown

OSIRIS - Satellite SAR imagery processing for vessel kinematics estimation
Reggiannini M.
Navigating vessels detection, identification and kinematics parameters estimation are relevant tasks concerning maritime surveillance and monitoring. One way to perform such operations is to process maps captured by Synthetic Aperture Radar (SAR) sensors installed on board of satellite constellations orbiting around earth-centered trajectories. Navigating vessels leave traces of their motion in the form of wake patterns on the water surface. Wakes are visible in high resolution SAR maps and bear information related to the kinematic variables of the vessel motion. A proper processing of the wake system allows to estimate the orientation of the vessel motion and the velocity module. This information can be exploited in the implementation of decision procedures dedicated to the control of maritime traffic. This document describes the design and implementation of software procedures with the purpose of estimating the motion parameters of a navigating vessel, through the processing of the wake pattern generated by the vessel itself.

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2017 Conference object Unknown

Nonlinear model selection for PARMA processes using RJMCMC
Karakuå? O., Kuruoglu E. E., Altinkaya M. A.
Many prediction studies using real life measurements such as wind speed, power, electricity load and rainfall utilize linear autoregressive moving average (ARMA) based models due to their simplicity and general character. However, most of the real life applications exhibit nonlinear character and modelling them with linear time series may become problematic. Among nonlinear ARMA models, polynomial ARMA (PARMA) models belong to the class of linear-in-the-parameters. In this paper, we propose a reversible jump Markov chain Monte Carlo (RJMCMC) based complete model estimation method which estimates PARMA models with all their parameters including the nonlinearity degree. The proposed method is unique in the manner of estimating the nonlinearity degree and all other model orders and model coefficients at the same time. Moreover, in this paper, RJMCMC has been examined in an anomalous way by performing transitions between linear and nonlinear model spaces.Source: EUSIPCO 25th European Signal Processing Conference, Kos, Greece, 28 August - 2 September 2017

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2017 Conference object Unknown

Medicina e telemedicina sulle montagne italiane
Pratali L., Martinelli M.
Stato dell'arte della telemedicina in montagna e il caso del progetto europeo e-Rés@mont.Source: XIX Congresso della Società Italiana di Medicina di Montagna, in congiunzione con International Mountain Summit 2017, Bressanone, Italy, 13-14 ottobre 2017

See at: CNR People | www.societaitalianamedicinadimontagna.it


2017 Article Open Access OPEN

One-day ahead wind speed/power prediction based on polynomial autoregressive model
Karakus O., Kuruoglu E. E., Altinkaya M. A.
Wind has been one of the popular renewable energy generation methods in the last decades. Foreknowledge of power to be generated from wind is crucial especially for planning and storing the power. It is evident in various experimental data that wind speed time series has non-linear characteristics. It has been reported in the literature that nonlinear prediction methods such as artificial neural network (ANN) and adaptive neuro fuzzy inference system (ANFIS) perform better than linear autoregressive (AR) and AR moving average models. Polynomial AR (PAR) models, despite being non-linear, are simpler to implement when compared with other non-linear AR models due to their linear-in-the-parameters property. In this study, a PAR model is used for one-day ahead wind speed prediction by using the past hourly average wind speed measurements of Ce?me and Bandon and performance comparison studies between PAR and ANN-ANFIS models are performed. In addition, wind power data which was published for Global Energy Forecasting Competition 2012 has been used to make power predictions. Despite having lower number of model parameters, PAR models outperform all other models for both of the locations in speed predictions as well as in power predictions when the prediction horizon is longer than 12 h.Source: IET renewable power generation (Print) 11 (2017): 1430–1439. doi:10.1049/iet-rpg.2016.0972
DOI: 10.1049/iet-rpg.2016.0972

See at: DSpace@IZTECH Open Access | DOI Resolver | CNR People | www.scopus.com


2017 Report Unknown

OSIRIS - Features DataBase
Martinelli M., Tampucci M., Righi M., Salerno E.
The Features DataBase is part of the activity in the OSIRIS Project and it is a support for the classification algorithm in order to recognize the vessel class from a satellite image.

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2017 Conference object Unknown

Servizio di teleconsulto medico innovativo e-Rés@mont
Pratali L., Martinelli M.
La presentazione illustra i risultati del sistema di teleconsulto medico durante la fase estiva del progetto e-Rés@mont.Source: Conferenza finale del progetto e-Rés@mont, Courmayeur, Italy, 7/12/2017

See at: CNR People | www.fondazionemontagnasicura.org


2017 Article Unknown

Restoration of ancient documents using sparse image representation
Hanif M., Tonazzini A.
Archival, ancient manuscripts constitute a primary carrier of information about our history and civilisation process. In the recent past they have been the object of intensive digitisation campaigns, aimed at their preservation, accessibility and analysis. At ISTI-CNR, the availability of the diverse information contained in the multispectral, multisensory and multiview digital acquisitions of these documents has been exploited to develop several dedicated image processing algorithms. The aim of these algorithms is to enhance the quality and reveal the obscured contents of the manuscripts, while preserving their best original appearance according to the concept of "virtual restoration". Following this research line, within an ERCIM "Alain Bensoussan" Fellowship, we are now studying sparse image representation and dictionary learning methods to restore the natural appearance of ancient manuscripts affected by spurious patterns due to various ageing degradations.Source: ERCIM news 111 (2017): 30–31.

See at: ercim-news.ercim.eu | CNR People


2017 Conference object Unknown

Making use of continuous measurements for change detection purposes: an application to water distribution networks
Scozzari A., Brozzo G.
The monitoring and control of industrial processes often requires the capability to identify particular patterns in a set of acquired measurements. One of the most recurrent applications consists in the detection of changes and the related minimization of false alarms. This requirement is true also when dealing with natural systems. The monitoring of a natural resource usually involves the identification of a set of parameters, which are considered as representative of its underlining processes, in order to extract useful information about its current status and its expected behavior. This work is focused on the water resources destined to the drinkable water distribution, paying attention to two particular aspects: i) the need for a suitable metric to detect anomalous values in the assessment of water quality indicators; ii) the experimentation of a simplified data-driven strategy to estimate natural variations of one or more indicators, in order to mitigate false alarms. This paper proposes a preliminary investigation and a selected case study, in order to exemplify one practical implementation of the proposed approach. The possible application to a context of low-cost distributed sensors is also briefly discussed.Source: I2MTC 2017 - IEEE International Instrumentation and Measurement Technology Conference, Torino, Italy, 22-25 May 2017
DOI: 10.1109/I2MTC.2017.7969738

See at: DOI Resolver | ieeexplore.ieee.org | CNR People


2017 Conference object Unknown

Effects of climate change on groundwater: observed and forecasted trends on Italian systems
Doveri M., Menichini M., Provenzale A., Scozzari A.
Groundwater represents the main source of water supply at global level. In Italy, as well as in most European countries, water needs are mainly covered by groundwater exploitation. The reliance on this resource is continuously growing, given the key role that groundwater plays for mitigating the climate change/variability and for addressing the significant increase in the global water demand. Despite this, and unlike surface waters, groundwater bodies have not been widely studied, and there is a general paucity of quantitative information, especially in relation to climate change. Although groundwater systems are more resilient to climate change than surface waters, they are affected both directly and indirectly. The estimation of the entity of these effects is mandatory for a reliable management of this crucial resource. The analysis of hydro-meteorological data over a few decades highlights that also the Italian territory is experiencing a change of the climate regime. Besides the increase of mean annual temperature, observed in particular since the early 1980s, longer and more frequent drought periods have been registered, as well as an increase of extreme events characterized by heavy rainfall. It is also noticeable a decrease in total rainfall, that is much more evident in the period from January to June. In addition to the reduced yearly inputs from precipitation, such trends determine also a lower snow accumulation and earlier snow melt in mountain areas, a general increase of evapotranspiration rates and an increased runoff fraction of the effective rainfall amount. As flood hydrographs of several major Italian rivers (e.g., Po, Brenta and Arno rivers) confirm, evident effects concern surface water resources. The main observed phenomena consist in the decline of mean annual discharge, the increase of extreme events with high discharge concentrated in short periods, and longer and earlier periods of low base flow. Impacts on groundwater recharge are not well understood. However, data analysis at specific Italian sites indicate that they are actually occurring. Here we discuss the results of the analysis of the data provided by a set of groundwater monitoring sites, not affected by artificial water extraction. Data refer to flowrates in spring and water levels from piezometers, and they are representative of different typologies of aquifers, such as karst, fractured and unconsolidated, located in mountain and foothills areas of central and northern Italy. Both flowrates and water levels indicate a decline of groundwater yields in these systems over the last two decades. This trend is much more evident when focusing on the periods of high level conditions (i.e. maximum effect of infiltrated water), thus demonstrating the reduction of recharge. The more attenuated trend observed by analyzing low level periods (i.e. at the end of dry periods) testifies the buffer role of aquifers, which partially compensate the general reduction by releasing water from storage reserves. A tendency to consume more recharge water through sudden and short flow rate peaks is also observed for karst systems, as a consequence of the increased occurrence of storm events. Furthermore, data were elaborated in order to study possible empirical relationships between meteorological parameters and groundwater quantity indices, in the wider framework of a research concerning the estimation of the performance of groundwater systems under specific climate scenarios.Source: EGU 2017 - General Assemblies of the European Geosciences Union, Vienna, Austria, 23-28 April 2017

See at: meetingorganizer.copernicus.org | CNR People


2017 Conference object Unknown

How the availability of free satellite data can improve the observation of critical infrastructures: a proposed application to landfills for municipal solid wastes
Scozzari A., Masetti G., Raco B., Battaglini R.
Landfills for Municipal Solid Wastes (MSW) produce about 20% of the total anthropogenic methane released to the atmosphere. As a consequence, these infrastructures require a systematic and efficient monitoring. Various techniques have been proposed until now for the estimation of biogas production and its release, by using more or less direct measurements, mostly characterised by a low or completely absent invasivity. During the last 13 years, observational data about a MSW disposal site located in Tuscany (Italy) have been collected on a regular basis, consisting in direct measurements of gas flux with the accumulation chamber method, combined with infrared radiometry performed in situ with portable radiometers. The availability of free Landsat imagery and the more recent availability of ASTER data (freely available since April 2016) open new monitoring possibilities, in addition to the in situ measurements described above. In particular, we present the preliminary results of a study about the usability of low resolution thermal infrared scenes to build timeseries describing the overall status of a waste disposal site. This work discusses the possibility to complement in situ measurements with satellite observations, taking benefit from the high revisit time with respect to the timings of in situ campaigns.Source: EGU 2017 - General Assemblies of the European Geosciences Union, Vienna, Austria, 23-28 April 2017

See at: meetingorganizer.copernicus.org | CNR People


2017 Conference object Unknown

Considerazioni sulle caratteristiche di amplificatori acustici economici nei confronti delle protesi acustiche
Bertini G., Magrini M., Riccobaldi M.
The presence on the market of acoustic amplifiers (defined as Personal Sound Amplifier Products - PSAPs and usually similar aesthetically to hearing aids) unaccompanied by adequate information, can attract the attention of people with hearing problems, creating confusion in the sector and doubts about their actual technical performance. The aim of our investigation was to carry out suitable measurements regarding the electroacoustic characteristics of several typical models of these devices, usually not supplied with the PSAPs. The work includes some considerations on possible problems as a resulting from their use by people with hearing loss.Source: Associazione Italiana di Acustica - 44° Convegno Nazionale, Pavia, Italy, 7-9 giugno 2017

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