Search results for "Opera"
showing 10 items of 8665 documents
Helical Shift Mechanics of Rubber V-Belt Variators
2011
A very common configuration of V-belt variators for motorcycles considers the correction of the belt tensioning depending on the resistant torque by means of suitable helical-shaped tracks allowing the driven half-pulleys to close/open. The theoretical model for belt-pulley coupling is rather complex for this configuration, where one half-pulley may run in advance and the other one behind with respect to the belt, and requires the repeated numerical solution of a strongly nonlinear differential system by a sort of shooting technique, until all the operating conditions are fulfilled (angular contact extent, torque, and axial force). After solving the full equations, the present study develop…
A Multi-Objective Design Approach for the c Chart Considering Taguchi Loss Function
2013
The present paper proposes a multi-objective design approach for the c chart, considering in the optimization process of the chart parameters both the statistical and the economic objectives. In particular, the minimization of the hourly total quality related costs is the considered objective to carry out the economic goal, whereas the statistical objective is reached by the minimization the out-of-control average run length of the chart. A mixed integer non-linear constrained mathematical model is formulated to solve the treated multi-objective optimization problem, whereas the Pareto optimal frontier is described by the e-constraint method. In order to show the employment of the proposed …
Comparing the Economic Effectiveness of Various Adaptive Schemes for the c Chart
2013
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. Th…
An Effective Double Sampling Scheme for thecControl Chart
2013
In the present paper is developed a statistical process control inspection procedure based on a new simple-to-implement and effective double sampling scheme for the c control chart, aimed at the minimization of the number of inspected observation units and warranting fixed levels for the type I and II error risks. In particular, the formulations of the false alarm risk α, the power P of the chart, and the expected number of inspected observation units for the developed inspection procedure are given, whereas a macro of Microsoft Excel is adopted to solve the tackled problem. In order to illustrate the application of the developed approach and to investigate on the influence of several opera…
Economic Design Approach for an SPC Inspection Procedure Implementing The Adaptive C Chart
2013
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 dev…
Artesanías evanescentes de la Edad del Hierro en la península Ibérica
2020
El proyecto «Madera, hueso, marfil, asta y concha. ¿Artesanías marginales o marginadas?» (HAR2013-45770-P) (2014-2017) se inició como continuidad de los proyectos de investigación desarrollados sobre la flora y la fauna de los iberos (2004-2012). En él se recogen útiles y adornos realizados en materias orgánicas de origen animal y vegetal de época ibérica que han pasado desapercibidos para la investigación. Por falta de financiación se han tratado menos a fondo las materias primas vegetales y malacológicas. Por su parte, para las materias duras animales se han analizado las cadenas operativas al completo (tratamiento, elaboración y consumo), los objetos elaborados, las formas de transmisión…
Piezas de hueso, asta, cuerno y marfil en época ibérica. De su elaboración a su interpretación
2019
Este trabajo tiene como objetivo principal analizar y dar visibilidad a los objetos elaborados sobre materias duras de origen animal (hueso, asta, cuerno y marfil) de época ibérica (s. VI – s. I a. C.). La revisión de los objetos se ha centrado en los recuperados en espacios de hábitat con el objetivo de documentar posibles lugares de elaboración de este tipo de artesanías dentro de los poblados iberos. Los artefactos han sido estudiados desde perspectivas múltiples. Así, en primera instancia todos los objetos han sido analizados anatómica y taxonómicamente con la finalidad de documentar qué especies animales y qué partes anatómicas se emplearon para su manufactura. Se han considerado tanto…
Patrimonio culturale a rischio. Una risposta dall'Europa. Il Progetto Polirisk - Politiques comparées: patrimoine, aménagement et risques naturels
2008
CD multimediale della rivista "Complessità e sostenibilità. Il territorio e l'architettura, 2008". L'articolo descrive il Progetto Polirisk, uno dei 12 sottoprogetti della Opération Cadre Régionale Noé – Patrimoine et Prévention des Risques Naturels, finanziata dalla Commissione Europea all’interno del Programma di Iniziativa Comunitaria (PIC) Interreg IIIC Sud per il periodo 2006-2008. Le regioni che compongono il partenariato, diretto dal Consiglio Regionale Provence-Alpes-Côte-d’azur (France), chef de file del progetto, vedono riunita una significativa parte dell’Europa attorno al tema della prevenzione del patrimonio culturale e ambientale dai rischi naturali: l’Attica dell’Est per la G…
Risk management in the banking industry
2016
El negocio bancario está altamente regulado porque las instituciones financieras captan ahorro público y tienen riesgos específicos y complejidades que hacen que sus estados financieros sean opacos y difíciles de analizar por el público en general (Petrella y Resti, 2013; Morgan, 2001). Para entender y monitorear los riesgos específicos en las empresas del sector financiero, el regulador estadounidense diseñó el sistema de evaluación CAMELS, que es comúnmente utilizado por los reguladores de todo el mundo para evaluar la solidez de las instituciones financieras y para evaluar el nivel de riesgo de los bancos (Office of the Comptroller of the Currency, 2013). Los riesgos que este enfoque eva…
Circulating Levels of Ferritin, RDW, PTLs as Predictive Biomarkers of Postoperative Atrial Fibrillation Risk after Cardiac Surgery in Extracorporeal …
2022
Postoperative atrial fibrillation (POAF) is the most common arrhythmia after cardiac surgery in conventional extracorporeal circulation (CECC), with an incidence of 15–50%. The POAF pathophysiology is not known, and no blood biomarkers exist. However, an association between increased ferritin levels and increased AF risk, has been demonstrated. Based on such evidence, here, we evaluated the effectiveness of ferritin and other haematological parameters as POAF risk biomarkers in patients subjected to cardiac surgery. We enrolled 105 patients (mean age = 70.1 ± 7.1 years; 70 men and 35 females) with diverse heart pathologies and who were subjected to cardiothoracic surgery. Their blood sample…