University Gdannunzio

Pescara, Italy

University Gdannunzio

Pescara, Italy
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Masciotta M.-G.,University of Minho | Ramos L.F.,University of Minho | Lourenco P.B.,University of Minho | Vasta M.,University Gdannunzio
Mechanical Systems and Signal Processing | Year: 2017

Structural monitoring and vibration-based damage identification methods are fundamental tools for condition assessment and early-stage damage identification, especially when dealing with the conservation of historical constructions and the maintenance of strategic civil structures. However, although the substantial advances in the field, several issues must still be addressed to broaden the application range of such tools and to assert their reliability. This study deals with the experimental validation of a novel method for non-destructive damage identification purposes. This method is based on the use of spectral output signals and has been recently validated by the authors through a numerical simulation. After a brief insight into the basic principles of the proposed approach, the spectral-based technique is applied to identify the experimental damage induced on a masonry arch through statically increasing loading. Once the direct and cross spectral density functions of the nodal response processes are estimated, the system's output power spectrum matrix is built and decomposed in eigenvalues and eigenvectors. The present study points out how the extracted spectral eigenparameters contribute to the damage analysis allowing to detect the occurrence of damage and to locate the target points where the cracks appear during the experimental tests. The sensitivity of the spectral formulation to the level of noise in the modal data is investigated and discussed. As a final evaluation criterion, the results from the spectrum-driven method are compared with the ones obtained from existing non-model based damage identification methods. © 2016 Elsevier Ltd


Schifano F.,University of Hertfordshire | Schifano F.,St George's, University of London | Martinotti G.,University Gdannunzio | Cunniff A.,University of Edinburgh | And 3 more authors.
American Journal on Addictions | Year: 2012

We set out to examine the impact of treatment for heroin dependence on drug use, injecting behavior, health problems, criminality, and physical and mental health over 18 months among heroin-dependent Londoners. A total of 100 heroin users were recruited for this longitudinal prospective cohort study with repeated measures (T0 as baseline, T1 after 9 months, and T2 after 18 months). The psychiatric evaluation and assessment of drug abuse levels were determined by the CIDI and the EuropASI. Additional evaluations included the WHO-DAS II for disability assessment and the UCLA-SSI for social support. The number of days of heroin use in the 30 days previous to each single assessment significantly reduced over time (p < .001). Similar reduction levels were observed for cocaine (p<.05), benzodiazepines (p<.001), and polydrug abuse (p<.001), but not for cannabis and alcohol. The number of injecting occasions reduced in parallel, with increase in days in work and reduction of money spent for drug acquisition activities and money obtained from criminal/illegal activities. The number of subjects experiencing suicidal ideation reduced over time (p<.05). In line with previous suggestions, significant reductions in drug use, criminality, psychopathology, and injecting behavior following treatment exposure for heroin dependence were observed. It is, however, of concern that alcohol and cannabis misuse levels remained unchanged. Copyright © American Academy of Addiction Psychiatry.


Masciotta M.-G.,University of Minho | Ramos L.F.,University of Minho | Lourenco P.B.,University of Minho | Vasta M.,University Gdannunzio | De Roeck G.,Catholic University of Leuven
Mechanical Systems and Signal Processing | Year: 2016

The present paper focuses on a damage identification method based on the use of the second order spectral properties of the nodal response processes. The explicit dependence on the frequency content of the outputs power spectral densities makes them suitable for damage detection and localization. The well-known case study of the Z24 Bridge in Switzerland is chosen to apply and further investigate this technique with the aim of validating its reliability. Numerical simulations of the dynamic response of the structure subjected to different types of excitation are carried out to assess the variability of the spectrum-driven method with respect to both type and position of the excitation sources. The simulated data obtained from random vibrations, impulse, ramp and shaking forces, allowed to build the power spectrum matrix from which the main eigenparameters of reference and damage scenarios are extracted. Afterwards, complex eigenvectors and real eigenvalues are properly weighed and combined and a damage index based on the difference between spectral modes is computed to pinpoint the damage. Finally, a group of vibration-based damage identification methods are selected from the literature to compare the results obtained and to evaluate the performance of the spectral index. © 2015 Elsevier Ltd. All rights reserved.


Marietti M.,University Gdannunzio | Testa D.,University of Warwick
European Journal of Combinatorics | Year: 2012

We introduce and study the notions of conical and spherical graphs. We show that these mutually exclusive properties, which have a geometric interpretation, provide links between apparently unrelated classical concepts such as dominating sets, independent dominating sets, edge covers, and the homotopy type of an associated simplicial complex. In particular, we solve the problem of characterizing the forests whose dominating sets of minimum cardinality are also independent. To establish these connections, we prove a formula to compute the Euler characteristic of an arbitrary simplicial complex from a set of generators of its Stanley-Reisner ideal. © 2012 Elsevier Ltd.


Sepe V.,University of Chieti Pescara | Spacone E.,University of Chieti Pescara | Verazzo C.,University Gdannunzio
COST ACTION C26: Urban Habitat Constructions under Catastrophic Events - Proceedings of the Final Conference | Year: 2010

This paper presents the early results of thework carried out by a group of researchers in support of the reconstruction efforts in the municipality of Poggio Picenze (near L'Aquila), where the April 6, 2009 L'Aquila earthquake severely damaged the historical center. The research group is interdisciplinary and includes structural engineers, architectural designers, city planners, architectural conservation experts, geologists and industrial designers. The main objectives of the proposed activities are to define reference guidelines for the conservation, rehabilitation, and safety enhancement of the built environment of the historical center of Poggio Picenze. These guidelines are the results of consultations with the regional reconstruction authorities, that supervise the postemergency activities in the L'Aquila region. Together with the local authorities, the reconstruction scenarios consider the gradual old town reopening within a more general scheme of social and economic revitalization of the town and the surrounding areas. The following pages present the results of the first year of work, that was basically spent gathering information regarding the town before the earthquake and the damage assessment primarily in the historical center. © 2010 Taylor & Francis Group, London.


Biasone A.,Valagro SpA | Cianci G.,Valagro SpA | Di Tommaso D.,Valagro SpA | Piaggesi A.,Valagro SpA | D'Alessandro N.,University Gdannunzio
Journal of Chromatography A | Year: 2013

Among the commercial ethylenediamine-N,N'-bis(2-hydroxy)phenylacetic acid/iron(III) derivatives, ethylenediamine-N,N'-bis(2-hydroxy-5-sulphophenylacetic) acid/iron(III) (EDDHSA/Fe) represents one of the promising chelates for the treatment of chlorotic plants. Industrial synthesis of EDDHSA/Fe leads to relevant amounts of o,o-EDDHSA condensation products (o,o-EDDHSAcps) and other secondary products that might have important relevance from the agronomic point of view. However, their chemical structures have remained unknown to date. Analysis of iron complexes by ion-pair reversed-phase chromatography, coupled with electrospray tandem mass spectrometry revealed the presence of the meso-o,o-EDDHSA/Fe, rac-o,o-EDDHSA/Fe, o,p-EDDHSA/Fe regioisomers, the hydroxyl derivative of o,o-EDDHSA/Fe, and the three main EDDHSA condensation products chelating the iron(III) (EDDHSAcps/nFe). However, the chromatographic peaks of EDDHSAcps/Fe are not well resolved due to the large numbers of stereoisomers and the poor efficiency of the ion-pair reversed-phase separation method. An alternative chromatographic method is based on porous graphitic carbon (PGC) separation after pre-column decomplexation of the chelates with trifluoracetic acid, which was developed to allow detection of EDDHSA stereo/regioisomers, EDDHSAcps, and low-molecular-weight by-products. This extensive PGC-HPLC-ESI-MS/MS investigation provides quantitative determination of meso-o,o-EDDHSA, rac-o,o-EDDHSA and o,p-EDDHSA, in addition to characterisation of EDDHSAcps and the low-molecular-weight by-products. PGC separation coupled to a triple quadrupole ESI-MS detector allowed characterisation of free ligands using collision-induced dissociation experiments in positive and negative ionisation mode, providing comparative evaluation of EDDHSAcps in three commercial samples. For detection, the PGC-HPLC-ESI-MS/MS is the best method according to the limit of quantification and limit of detection (picomolar and sub-picomolar detection, respectively) for determination of meso-EDDHSA and rac-o,o-EDDHSA. Synthesis, purification and quantification of o,o-EDDHSA and o,p-EDDHSA by 1H-nuclear magnetic resonance are also reported. © 2013 Elsevier B.V.


Currently the therapeutic gold standard for medium and low rectal tumours is the "en-bloc" excision of the rectum and total mesorectal excision (TME) preserving the autonomous nerve plexus. In very distal tumours, complex procedures such as very low anterior resections and intersphincteric resections are used where possible. These procedures can avoid incapacitating operations such as abdominoperineal amputation. The possibilities to perform these procedures even by laparoscopic means, with regard to it's advantages, are still under evaluation. The authors describe their own clinical experiences using such methods. From 2005 to 2010, we performed by laparoscopic procedure 3 anterior resections and 3 inter-sphincteric resections for cancer of the low rectum . Medium age of patients was 70 years (range 52-80 years) and male to female ratio was 4/2. Mean operative time was 260 min ( range 220 - 360 min). No laparoscopic procedure was converted to the traditional open surgery. We noted 2 anastomotic leakages of which one required re-operation. Two patients were classified T2 (1 N0 and 1 N1); four patients T3 (3 N0 and 1 N2). In all the cases, resection margins were free. The mean distance from the anal verge was 3,8 cm (range 2,8 - 6 cm). In a mean followup of 48 months ( range 6-54 months), 1 patient developed hepatic metastasis and no local recurrence was noted. Two patients had urinary retention, resolved spontaneously. One patient presented erectile dysfunction. At 12 months from the operation, one patient had slight incontinence for gas and liquids. We believe that total mesorectal resection, even associated with sphincter preserving procedures, such as intersphincteric resection, in case of very low rectal tumours, can also be performed by laparoscopic approach with the same oncological and surgical principles of open surgery. However it is necessary to have broad based studies and randomised clinical trials in order to confirm the safety of such procedure and the results obtained.


Eboli M.,University Gdannunzio
Intelligent Systems Reference Library | Year: 2015

This contribution focuses on the methodology applied in papers that investigate the dynamics of contagion in financial networks using numerical simulations. In these papers, a propagation of losses and defaults in a financial system is modeled as a direct balance-sheet contagion (a.k.a. counterparty contagion), that is the direct transmission of losses from financially distressed debtors to their creditors. The researchers in this field perform their simulations with three different methods: (i) basic linear threshold algorithms, (ii) the graph-theoretic approach, where contagion is modeled as a propagation process in directed and weighted graphs, (iii) the lattice-theoretic approach, where contagion is modeled as a ‘fictitious default algorithm’, that computes the vector of payments that clears a net of financial obligations. Some of the results obtained by this stream of literature raised doubts about the assumptions used in such simulations. We discuss this issue and present some methodological recommendations that may improve the realism and the generality achievable in numerical investigations of financial contagion. © Springer International Publishing Switzerland 2015.


Campli P.,University Gdannunzio
Leibniz International Proceedings in Informatics, LIPIcs | Year: 2011

In this paper a general framework (based on soft constraints) to model and solve the fair allocation problem is proposed. Our formal approach allows to model different allocation problems, ranging from goods and resources allocation to task and chore division. Soft constraints are employed to find a fair solution by respecting the agents's preferences; indeed these can be modeled in a natural fashion by using the Semiring-based framework for soft constraints. The fairness property is considered following an economical point of view, that is, taking into account the notions of envy-freeness (each player likes its allocation at least as much as those that the other players receive, so it does not envy anybody else) and efficiency (there is no other division better for everybody, or better for some players and not worse for the others).


PubMed | University Gdannunzio
Type: Journal Article | Journal: Il Giornale di chirurgia | Year: 2011

Currently the therapeutic gold standard for medium and low rectal tumours is the en-bloc excision of the rectum and total mesorectal excision (TME) preserving the autonomous nerve plexus. In very distal tumours, complex procedures such as very low anterior resections and intersphincteric resections are used where possible. These procedures can avoid incapacitating operations such as abdominoperineal amputation. The possibilities to perform these procedures even by laparoscopic means, with regard to its advantages, are still under evaluation. The authors describe their own clinical experiences using such methods.From 2005 to 2010, we performed by laparoscopic procedure 3 anterior resections and 3 inter-sphincteric resections for cancer of the low rectum . Medium age of patients was 70 years (range 52-80 years) and male to female ratio was 4/2. Mean operative time was 260 min ( range 220 - 360 min). No laparoscopic procedure was converted to the traditional open surgery. We noted 2 anastomotic leakages of which one required re-operation. Two patients were classified T2 (1 N0 and 1 N1); four patients T3 (3 N0 and 1 N2). In all the cases, resection margins were free. The mean distance from the anal verge was 3,8 cm (range 2,8 - 6 cm). In a mean followup of 48 months ( range 6-54 months), 1 patient developed hepatic metastasis and no local recurrence was noted. Two patients had urinary retention, resolved spontaneously. One patient presented erectile dysfunction. At 12 months from the operation, one patient had slight incontinence for gas and liquids.We believe that total mesorectal resection, even associated with sphincter preserving procedures, such as intersphincteric resection, in case of very low rectal tumours, can also be performed by laparoscopic approach with the same oncological and surgical principles of open surgery. However it is necessary to have broad based studies and randomised clinical trials in order to confirm the safety of such procedure and the results obtained.

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