Search results for "metrica"
showing 10 items of 196 documents
Multiparametric-MRI evaluation of cervical nodes in patients with head and neck squamous cell carcinoma (HNSCC)
The stenopaeic slit: an analytical expression to quantify its optical effects in front of an astigmatic eye.
2001
The stenopaeic slit is a trial case accessory used in subjective refraction, especially when high astigmatism is present. In spite of its simplicity, the effect of the slit when it is not oriented along one of the principal meridians of the examined eye is difficult to predict, even in terms of classical geometrical optics. In this paper, the optical principles of the slit are considered with full details in the theoretical framework of the dioptric power space. An analytical expression to obtain the residual refractive error when a stenopaeic slit is placed in front of an astigmatic eye at any orientation is deduced. In the light of these results, some aspects of the clinical procedure are…
Influence of some relevant process parameters on the dimensional accuracy in incremental forming: a numerical and experimental investigation
2004
Abstract As known, incremental forming is a flexible and innovative sheet metal forming process which allows complex shape shells forming without the need for any die. For these reasons, incremental forming is nowadays suggested for rapid prototyping and customised products. The present paper is focused on material formability in incremental forming and, in particular, on the evaluation and compensation of elastic springback. The latter significantly modifies the imposed shape. For this purpose, a deeper assessment of the process was developed following three different approaches. First of all, a wide experimental investigation on the influence of some relevant process parameters was develo…
Enhanced modulation strategy for 7-level voltage waveform in asymmetrical 5-level Cascaded H-Bridge Inverters
2022
The CHBMI performance optimization can be reached both with hardware and software solutions. Generally, asymmetrical configurations allow the extension of the voltage levels number and the implementation of an innovative modulation strategy allows for improving the performance in terms of harmonic distortion and conversion efficiency. This work is devoted to the development of a modulation strategy that allows improving the performance of an asymmetrical single-phase five-level Cascaded H-Bridge Inverter generating a 7-level voltage waveform. Thus, a digital approach and corresponding digital functions are presented. Subsequently, the impact of the dead time and the influence on the voltage…
ANALISI BIOMETRICA DI VARIETA’ DI MORUS ALBA AI FINI DELLA IDENTIFICAZIONE E CLASSI- FICAZIONE
2014
Per gli storici c’è ancora una polemica circa l’origine ed il tempo della prima introduzione del gelso in Italia. Molti sono d’accordo che le due principali specie di gelso (Morus alba e M. nigra) provengono dall’Asia, la prima dalla Persia e la seconda dal lontano est. Sembra, comunque, che sia stato il gelso nero (Morus nigra) il primo ad essere adattato e coltivato per i suoi frutti, non solo a fini alimentari ma anche per scopi medicinali dai Greci e dai Romani (Bertelli Bargamaschi, 1994). Il gelso bianco, originario della Cina, è stato introdotto in occidente assieme al baco da seta nel XII secolo. La grande importanza del gelso bianco derivava infatti dal fatto che questo era un alim…