2,378 research outputs found

    Analysis of tide measurements in a Sicilian harbour

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    Designing of ports and coastal protection works as well as planning of coastal human activities require knowledge of tidal oscillations. The latter vary noticeably from site to site and present an “astronomic” component, which is roughly periodic, and a “meteorological” component which is usually considered as random. In this paper, the tidal oscillations observed in a Sicilian harbour in the period 1999-2009 are analysed statistically, in order to recognize a probability distribution which allows one to predict the highest tidal levels. First, the measurements are used to obtain, for each year, the astronomic tide by the harmonic analysis by the software package T_TIDE. The difference between the observed tide and the astronomic tide, indicated as “noise”, is imputed to meteorological factors and treated by a statistical approach. The noise imputable to sea storms moving onshore is divided from that imputable to storms moving offshore. Several probability distributions are then considered for each noise and it is established that each noise closely follows the Weibull extreme value distribution better than other distributions

    Storm sewer pressurization transient – an experimental investigation

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    Pipe pressurization is examined experimentally by 144 laboratory experiments in a circular tilting pipe between two tanks, in which the transient was triggered by sudden closing of the downstream tank outlet. The experiments cover ranges of values of slope, velocity and filling ratio of the open-channel flow not explored in previous studies. Situations involving considerable air quantity and consequent intense pressure oscillations were also reproduced. Two different pressurization patterns, defined as “smooth” and “abrupt”, were observed, but only the abrupt pattern produced intense pressure oscillations. The comparison among all the abrupt pressurization surges showed how the oscillations changed in starting time, intensity and duration as the pipe slope, the flow rate and the free-surface flow filling ratio varied. The experimental results also stressed the major role of entrapped air in determining the oscillation characteristics, showing that oscillations were actually produced by the pulsating of large air pockets during their migration along the pipe and their release through the upstream manhole

    Flow hydraulic characteristics determining the occurrence of either smooth or abrupt sewer pressurization

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    Laboratory experiments showed that pipe pressurization consequent on a drastic reduction in the downstream discharge can occur either by a gradual rising of the free-surface (“smooth” pressurization) or by propagation of a front filling the whole cross-section (“abrupt” pressurization). This study examines the free-surface flow characteristics that determine smooth or abrupt pressurization pattern through a theoretical approach using dimensionless variables. A critical flow rate value, which separates the pressurization patterns, exists for any given pipe diameter. For flow rates higher than this specific value, only abrupt pressurization occurs. For lower flow rates, either smooth or abrupt pressurization can take place; smooth pressurization occurs when the free-surface flow depth falls within a specified range, depending on the flow rate itself and the pipe diameter, whereas abrupt pressurization occurs when the depth falls outside this range. The comparison with actual uniform-flow conditions allows one to predict the pressurization pattern and the related pipe surcharge (in the case of abrupt pressurization). The analysis also shows that, in practice, severe surcharges can be expected even in the case of only partial reduction of the downstream discharge

    SEM-EDX and SEM-CL to Characterize Lapis Lazuli from Different Provenances

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    Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011

    Random wave run-up with a physically-based Lagrangian shoreline model

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    n the present paper the run-up of random waves was calculated by means of a numerical method. In situ measurements based on a video imaging technique have been used for the validation of the present numerical model. The on-site run-up measurements have been carried out at Lido Signorino beach, near Marsala, Italy,along a transect, normal to the shore. A video camera and a linear array of rods have been used to obtain field data. Numerical simulations with a 1DH Boussinesq-type of model for breaking waves which takes into account the wave run-up by means of a Lagrangian shoreline model have been carried out. In such simulations random waves of given spectrum have been propagated in a numerical flume having the same beach slope of the measured transect. The comparison between registered and estimated run-up underlined an acceptable agreement. Indeed, the numerical model tends to underestimate the actual R2%, with the maximum underestimate being less than 24%, which is a reasonable error in many cases of engineering interest

    Your Friends Mention It. What About Visiting It? A Mobile Social-Based Sightseeing Application

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    In this short poster paper, we present an application for suggesting attractions to be visited by users, based on social signal processing technique

    Esophageal motility changes after thyroidectomy; possible associations with postoperative voice and swallowing disorders: preliminary results.

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    Objective Swallowing and voice impairment are common after thyroidectomy. We evaluated short-term functional changes in esophageal motility in a series of patients who had undergone total thyroidectomy. Several studies have investigated these symptoms by means of interviews or questionnaires. Study Design Prospective study. Setting Academic research. Materials and Methods Thirty-six consenting patients were prospectively recruited. Eligibility criteria were thyroid volume ≤60 mL, benign disease, and age between 18 and 65 years. Exclusion criteria were previous neck surgery, severe thyroiditis, hyperthyroidism, and pre- or postoperative vocal cord palsy. Voice impairment score, swallowing impairment score, lower esophageal sphincter pressure, esophageal motility, upper esophageal pressure, and coordination were evaluated preoperatively and 30 to 45 days after surgery. Results Postoperative swallowing impairment (appearance or worsening of dysphagia) was found in 20% of patients and voice impairment in more than 30%. Both preoperative and postoperative esophageal motility were similar. All patients showed an average decrease of 25% in upper esophageal pressure, although the pressure was within normal range. Swallowing alterations were associated with upper esophageal incoordination (P < .03), and proximal acid reflux was significantly associated with voice impairment (P < .02). Conclusion After uncomplicated thyroidectomy, decreased upper esophageal pressure may explain both pharyngeal (dysphagia) and laryngeal (vocal impairment) exposure to acid. In the future, proton pump inhibitor therapy protocols should be evaluated

    Age determination and authentication of ceramics: advancements in the thermoluminescence dating laboratory in Torino (Italy)

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    13Classified as an absolute dating method, thermoluminescence (TL) is a well-established radiation-based technique for the age determination and authentication of ceramic materials. Specifically, this method allows the determination of the time elapsed since kiln firing (or later fire events) by evaluating the luminescent emission of ceramics under heating at high temperatures. This paper provides a comprehensive presentation of the TL laboratory developed over the last decade at the Physics Department of the University of Torino. The laboratory was set up in collaboration with TecnArt S.r.l. and is also currently operating within the cultural heritage network of the National Institute of Nuclear Physics (INFN-CHNet). More than 10 years of experience in the field has resulted in improvements in procedures, with the development of customised alpha- and beta-irradiation systems and the optimisation of sampling approaches and chemical pre-treatment. Thanks to TecnArt S.r.l., the laboratory has been employed for dating and authenticating hundreds of archaeological sites and artworks, some of which are discussed in this work and compared, when possible, with radiocarbon dating.openopenGuidorzi, Laura; Fantino, Fulvio; Durisi, Elisabetta; Ferrero, Marco; Re, Alessandro; Vigorelli, Luisa; Visca, Lorenzo; Gulmini, Monica; Dughera, Giovanni; Giraudo, Giuseppe; Angelici, Debora; Panero, Elisa; Lo Giudice, AlessandroGuidorzi, Laura; Fantino, Fulvio; Durisi, Elisabetta; Ferrero, Marco; Re, Alessandro; Vigorelli, Luisa; Visca, Lorenzo; Gulmini, Monica; Dughera, Giovanni; Giraudo, Giuseppe; Angelici, Debora; Panero, Elisa; Lo Giudice, Alessandr

    A multipurpose X-ray fluorescence scanner developed for in situ analysis

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    Abstract: Over the time, instrument transportability has become more and more important, especially in Cultural Heritage, as often artworks cannot be moved from their site, either because of the size or due to problems with permission issues, or simply because moving them to a laboratory is physically impossible, as e.g. in the case of mural paintings. For this reason, the INFN-CHNet, the network for Cultural Heritage studies of the Italian National Institute of Nuclear Physics (INFN), has developed an XRF scanner for in situ analyses. The instrument is the result of a wide collaboration, where different units of the network have been developing the diverse parts, then merged in a single system. The XRF scanner has been designed to be a four-season and green instrument. The control/acquisition/analysis software has been fully developed by our group, using only open-source software. Other strong points of the system are easiness of use, high portability, good performances and ultra-low radiation dispersion, which allows us to use even when the public can be present. It can run both with mains or on batteries, in the latter case with a maximum runtime longer than 10 h. It has a very low cost, when compared to commercial systems with equivalent performances, and easily replaceable components, which makes it accessible for a much wider portion of the interested community. The system has been thought and designed as an open system, suitable for further development/improvements, that can result interesting for non-conventional XRF analysis. The CHNet XRF scanner has proved to be really very well suited for applications in the Cultural Heritage field, as testified by the many recent applications. This paper describes the present version of our instrument and reports on the tests performed to characterise its main features.Fil: Taccetti, F.. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Castelli, L.. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Czelusniak, C.. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Gelli, N.. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Mazzinghi, A.. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Palla, L.. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Ruberto, C.. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Censori, C.. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Lo Giudice, A.. Università di Torino; Italia. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Re, A.. Università di Torino; Italia. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Zafiropulos, D.. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Arneodo, F.. New York University Abu Dhab; Emiratos Arabes UnidosFil: Conicella, V.. New York University Abu Dhab; Emiratos Arabes UnidosFil: Di Giovanni, A.. New York University Abu Dhab; Emiratos Arabes UnidosFil: Torres, R.. New York University Abu Dhab; Emiratos Arabes UnidosFil: Castella, F.. Universidad Nacional de San Martín. Instituto de Investigaciones sobre el Patrimonio Cultural; ArgentinaFil: Mastrangelo, Noemi Elisa. Universidad Nacional de San Martín. Instituto de Investigaciones sobre el Patrimonio Cultural; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gallegos, D.. Universidad Nacional de San Martín. Instituto de Investigaciones sobre el Patrimonio Cultural; ArgentinaFil: Tascon, Marcos. Universidad Nacional de San Martín. Instituto de Investigaciones sobre el Patrimonio Cultural; Argentina. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Marte, F.. Universidad Nacional de San Martín. Instituto de Investigaciones sobre el Patrimonio Cultural; ArgentinaFil: Giuntini, L.. Università degli Studi di Firenze; Itali
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