Sound insulation is measured for diffuse incidence too. Then, 3 Â 3 m sonic crystal noise barriers are installed in the Laboratory of the University of Bologna and sound insulation and sound reflection measurements are performed according to the mentioned active standards for normal incidence. Since the target frequency range for traffic noise spectrum is centred at around 1000 Hz, a finite element based parametric investigation is performed to design unit cells capable of generating band gaps in the one-third octave bands ranging from 800 Hz to 1250 Hz. Diffuse field measurements in laboratory are also done for comparison purposes. The aim of this work is to perform free-field measurements over a real-sized sample in order to window out all diffraction components and to verify the points of strength and weakness of the application of standardised measurements to sonic crystals. In most of the reference literature, sound insulation and reflection properties of sonic crystals are measured or a diffuse sound field or in a direct sound field including the top and side edge diffraction effects together with the transmitted (or reflected) components. This work presents sound insulation and sound reflection measurements conducted over sonic crystal noise barriers according to the European standards EN 1793-2, EN 1793-5 and EN 1793-6. The main resonances and noise levels are correctly estimated by the models implemented in MANATEE ® simulation software, and the calculation time does not exceed a few minutes on a single laptop including harmonics up to 20 kHz in the worst case. This model is validated by comparing simulation results to experimental results on several electrical machines at variable speed, including surface permanent magnet (SPMSM), interior permanent magnet (IPMSM) and squirrel cage induction machines (SCIM). In the second part, a new coupling of electrical, electromagnetic and vibro-acoustic models based on analytical and semi-analytical modeling techniques is presented. In the first part, some numerical methods for the prediction of electromagnetic noise are analyzed and compared to other calculation methods (analytical, semi-analytical and hybrid methods). Microsoft Windows SharePoint Services 2.-This paper presents a new multiphysic model and simulation environment for the fast calculation and analysis of acoustic noise and vibration levels due to Maxwell forces in variable-speed rotating electrical machines. Microsoft SQL Server 2005 (9.0) Workgroup Microsoft SQL Server 2005 (9.0) Developer Microsoft Windows Essential Business Server 2008 Microsoft Windows Small Business Server 2008 Microsoft Windows Server 2008 Standard Edition Microsoft Windows Server 2008 R2 Standard Edition Microsoft Windows Server 2008 R2 Enterprise Edition Microsoft Windows Server 2008 R2 Datacenter Edition Microsoft Windows Server 2008 Enterprise Edition Microsoft Windows Server 2008 Datacenter Edition Microsoft Windows XP Media Center Edition Recuperación Clave de Reserva Recupera Claves de Producto Para más de +2500 Productos de Software Puede guardar llaves del producto como la Etiqueta Archivo Txt Delimitado (.txt), Cuaderno de ejercicios de Excel (.xls), Coma de CSV Delimitada (.csv), Base de datos de Acceso (.mdb), Página Web (.html) o Datos XML (.xml) archivo, Letra o Copia a la Tabilla con sujetapapeles.
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