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Palermo, Italy

Milazzo A.,University of Palermo
Composite Structures | Year: 2012

An equivalent single-layer model for the dynamic analysis of magnetoelectroelastic laminated plates is presented. The electric and magnetic fields are assumed to be quasi-static and the first-order shear deformation theory is used. The formulation of the model provides for a preliminary fulfillment of the electro-magnetic governing equations, which allows to determine the electric and magnetic potential as functions of the mechanical variables. Then, by using this result, the equations of motion are written leading to the problem governing equations. They involve the same terms of the elastic dynamic problem weighted by effective stiffness coefficients, which take the magneto-electro-mechanical couplings into account. Additional terms, exclusively arising in force of the piezoelectric and piezomagnetic behavior, appear. The electromagnetic inputs are treated as equivalent external distributed axial forces and bending moments. Free and forced vibrations solutions for simply-supported plates are presented to validate the model by comparing the present results with benchmark solutions found in the literature. © 2012 Elsevier Ltd. Source

Orecchio S.,University of Palermo
Atmospheric Environment | Year: 2011

This study investigates PAHs indoor emissions from burning decorative candle in an indoor environment because emissions from burning wax in home have rarely been addressed. A total of 12 air samples were collected during the entire burning period of the decorative candles. Particulate and gaseous PAHs emissions were simultaneously measured by passing effluent through a filter (to collect particulate-phase PAHs), a cold trap and ORBO 43 tubes (to capture gaseous-phase PAHs). Analysis involved ultrasound extraction, followed by gas chromatography-mass spectrometry (GC-MS).The measured total PAHs concentration (particulate + aqueous phase + gas phases) for the candles, reported as mass of PAHs emitted/mass of candle burning, was between 2.3 and 49.8 μg kg-1 and mean 15 μg kg-1. Considering the volume of sampled air, the concentrations of total PAHs ranged from 7 ng m-3 to 267 ng m-3. Concentrations of B[a]P emitted by candles ranged from 0.1 to 7.5 ng m-3, while total carcinogenic PAHs, expressed as B[a]eq, ranged from 0.2 to 10.7 ng m-3. The values of all the isomeric indices calculated in this research are in good agreement to literature data for emissions from high temperature processes. © 2011 Elsevier Ltd. Source

Lupo T.,University of Palermo
Quality and Reliability Engineering International | Year: 2014

The present paper proposes a design approach for a statistical process control (SPC) procedure implementing a c control chart for non-conformities, with the aim to minimize the hourly total quality-related costs. The latter take into account the costs arising from the non-conforming products while the process is in-control and out-of-control, for false alarms, for assignable cause locations and system repairs, for sampling and inspection activities and for the system downtime. The proposed economic optimization approach is constrained by the expected hourly false alarms frequency, as well as the available labor resource level. A mixed integer non-linear constrained mathematical model is developed to solve the treated optimization problem, whereas the Generalized Reduced Gradient Algorithm implemented on the solver of Microsoft Excel is adopted to resolve it. In order to illustrate the application of the developed procedure, a numerical analysis based on a 2V5-1 fractional factorial design scheme, to investigate on the influence of several operating and costs parameters, is carried out, and the related considerations are given. Finally, the obtained results show that only few parameters have a meaningful effect on the selection of the optimal SPC procedure. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2013 John Wiley & Sons, Ltd. Source

Lupo T.,University of Palermo
Quality and Reliability Engineering International | Year: 2014

In an attempt to improve the effectiveness of statistical process control (SPC) procedures, a variety of adaptive schemes has been developed in the last decades. However, considering control charts for attributes, relatively few works about adaptive schemes have been proposed, and most of them were proposed only recently. The common characteristic of those schemes is that one or more chart parameters are allowed to adaptively vary during the SPC operations according to the sampling information history, typically the current point plotted on the chart. In this way, the adaptive schemes are smarter than the related static ones, but they are also more complicated in terms of implementation. The purpose of the present work is to evaluate and compare the economic performance of the main adaptive schemes of a control chart for attributes, in order to derive conclusions on their relative effectiveness. In particular, the analysis is focused on the c chart that is used to monitor the total nonconformities number in an inspection unit. A numerical comparative study, based on a 2V5-1 fractional factorial design scheme, to investigate on the influence of several operating and costs parameters, is carried out, and the related considerations are given. The obtained results show that the chart parameter having the most impact on the economic performance is the sampling interval. Therefore, in most cases, the use of a c chart with adaptive sampling intervals is the better choice than other adaptive schemes, which are also more complicated in terms of implementation. Copyright © 2013 John Wiley & Sons, Ltd. Source

Mercadante S.,University of Palermo
The Lancet Oncology | Year: 2010

In recent years, a growing interest in palliative care and in routes of administration other than oral have prompted more aggressive measures to improve the efficacy of analgesic interventions in patients with difficult pain conditions. This review provides an overview of the use of intravenous morphine to control pain in patients with cancer. Intravenous morphine has been increasingly used in different clinical situations-including breakthrough pain, poor pain control with escalating doses of oral opioids, retitrating patients with acute pain, treating patients with long-standing poor pain control and unpredictable needs, and optimising opioid therapy to prevent incident pain associated with bone metastases. Although intravenous administration requires supervision, it has considerable advantages, since direct administration into the circulation provides a rapid and predictable effect that is independent of absorption problems. IV morphine is advantageous in specific clinical situations and should be part of armamentarium of all physicians treating pain in patients with cancer. © 2010 Elsevier Ltd. Source

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