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Bari, Italy

The Polytechnic University of Bari is a university located in Bari, Italy. It was founded in 1990 and is organized in 3 Faculties. Wikipedia.

Introduction and objective: In computer aided diagnosis (CAD) tools searching for colonrectal polyps and based on three dimensions virtual colonoscopy (3DVC) using computed tomography (CT) images, the reduction of the occurrence of false-positives (FPs) still represents a challenge because they are source of unreliability. Following an encouraging previous supervised approach Bevilacqua et al., Three-dimensional Virtual Colonoscopy for Polyps Detection by Supervised Artificial Neural Networks D.-S. Huang et al. (Eds.): ICIC, LNBI 6840, Springer-Verlag, Berlin Heidelberg, (2011), pp. 596-603, the aim of this work is to discuss, in details, how the adopted strategies, designed and tested on an initial reduced data set, reveals good performance and robustness in terms of FPs reduction on an enlarged cohort of new cases. Materials and methods: At the beginning, materials consisted only in 10 different polyps, diagnosed, by expert radiologists, in 6 different patients, scanning 16 rows helical CT multi slices with a resolution of 1. mm. Moreover from those 10 polyps only 7 polyps were initially used for the analysis, excluding 2 tumors with diameter bigger than 1. cm, and one polyp hardly recognizable due to fecal stool. In this paper, thanks to a new accurate phase of collecting data, materials grow impressively and then consist in total of 43 polyps all useful for the study. The whole data set was merged by using the former data set of colonrectal exams from the clinical operative unit called "Sezione di Diagnostica per Immagini" of Di.M.I.M.P. of Policlinico of Bari and the new ones coming from two new collaborations: the Oncology department of Faculty of Medicine of University of Pisa participating, as the former, to the IMPACT study (Italian Multicenter Polyps Accuracy CTC Study) Regge, Linear and nonlinear feedforward neural network classifiers: a comprehensive understanding, J. Intell. Syst., 9 (1) 1999, 1-38 and, more recently, the operative unit of radiology of the "Istituto Tumori Giovanni Paolo II" of Bari. Starting from computed tomography colonography (CTC) images, several volumes were scanned by means of three different supervised artificial neural networks (ANNs) architectures based on error back propagation training algorithm Huang and Ma, Linear and nonlinear feedforward neural network classifiers: a comprehensive understanding, J. Intell. Syst., 9 (1) 1999, 1-38. All the training sets were built by using polyps and non-polyps sub-volume samples, whose dimensions were correlated to the volume of the polyps to be detected. Results: The performance of the best ANN architecture, trained by using a training set of 27 sessile polyps from the new 43 available dataset, were evaluated in terms of FPs and false-negatives and compared to the results shown in Bevilacqua et al., Three-dimensional Virtual Colonoscopy for Polyps Detection by Supervised Artificial Neural Networks D.-S. Huang et al. (Eds.): ICIC, LNBI 6840, Springer-Verlag, Berlin Heidelberg, (2011), pp. 596-603 where a cross validation strategy was used to overcome the small number of the old available dataset Huang, The bottleneck behaviour in linear feedforward neural network classifiers and their breakthrough, J. Comput. Sci. Technol., 14 (1) 1999, 34-43. Good performances in terms of generalization and robustness of the previous work, are then shown by the fact that the free-response operator characteristic analysis do not change significantly thanks to the enlargement of the available data. Conclusions: This testing determined that the supervised ANN approach is consistent and reveals good performance; at the same time it is fairly intuitive that it is necessary to train a method by using polyps and non-polyps samples and that, for this reason, the overall performance could be improved by a larger dataset diagnosed by expert radiologists. © 2012 Elsevier B.V. Source

Foti D.,Polytechnic of Bari
Composite Structures

In the present paper the results of some tests performed on concrete specimens reinforced with fibers made from waste polyethylene terephthalate (PET) bottles are reported. The fibers have been obtained by simply cutting the bottles; the fibers are then added to the mix concrete or they are used as discrete reinforcement of specimens and little beams in substitution of steel bars. The tests are to be considered as an approach to a more extensive investigation on the use of PET as a reinforcing material for concrete and masonry structures. The results that have been obtained are very interesting, especially regarding the adherence between PET and concrete, suggesting a possible use of this material in the form of flat or round bars, or networks for structural reinforcement. © 2012 Elsevier Ltd. Source

Messeni Petruzzelli A.,Polytechnic of Bari | Savino T.,University of San Marino
Long Range Planning

This study investigates the impact of searching and recombining old components in the development of successful innovations. Specifically, we identify the main characteristics of old components that contribute to enhance the value of innovations, as well as the mechanisms underlying their recombination. To this aim, we conduct an in-depth case study of the innovation process, characterizing the Danish haute cuisine chef René Redzepi, whose restaurant Noma was voted the best restaurant in the world in the 2010, 2011, and 2012 San Pellegrino Awards. Our analysis reveals that searching and recombining components across time may be beneficial for the success of an innovation, especially when they are culturally close to the inventor and relatively unexploited in the specific industry. Moreover, the positive contribution of old components is enhanced when they are recombined with other geographically proximate elements and when new techniques and solutions are employed. © 2012 Elsevier Ltd. Source

Carbone G.,Polytechnic of Bari | Pierro E.,University of Basilicata

Very recently, both experimental and theoretical investigations have shown that microstructured surfaces covered with mushroom-shaped micropillars present strongly enhanced adhesive properties if compared to flat surfaces made of the same material. However, different geometries lead to different adhesive performance, and finding the optimal solution has become of utmost importance. This paper presents on which physical basis the optimal mushroom pillar shape should be sought, and it provides a relatively simple methodology to achieve the result. Calculations demonstrate that the adhesive performance of the pillar strongly depends on the geometry of the terminal plate. The best performance is achieved when the ratio s/Ri between the plate thickness (s) and the pillar internal radius (Ri) is close to 0.2-0.3, and the ratio R e/Ri is larger than 2, where Re is the external radius of the plate. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

One of the main difficulties, when dealing with landslide structural vulnerability, is the diagnosis of the causes of the crack pattern. This is also due to the excessive complexity of models based on classical structural mechanics that makes them inappropriate especially when there is the necessity to perform a rapid vulnerability assessment at the territorial scale. This is why in this article a new approach for the rapid diagnosis of crack patterns of masonry buildings subjected to landslide-induced settlements is proposed. This approach is based on the Load Path Method, recently applied to the interpretation of the behavior of masonry buildings subjected to landslide-induced settlements. © 2016 Taylor & Francis. Source

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