94,176 research outputs found
Shunt-connected microstrip radial stubs
No full textRadial line stubs provide an interesting alternative to low-impedance conventional straight stubs. They are useful as filter elements in both series and shunt configurations. The planar circuit analysis previously performed (F. Giannini et al. ; ibid. , vol. MTT-32, no. 12, pp. 1652-1655, 1984) for a series-connected radial stub is extended to the shunt configuration. Theoretical and experimental results are presented to verify the equivalent model for the shunt-connected radial stub
Topology optimization of MEMS resonators with target eigenfrequencies and modes
No full textsponsorship: Daniele Giannini and Francesco Braghin acknowledge the financial support of STMicroelectronics, Switzerland (grant code 081/16CR) . They also thank the AMG R&D team of STMicroelectronics, who pro-vided the industrial insight and expertise that greatly assisted the research. Daniele Giannini acknowledges the partial financial support received in the framework of the ERC Starting Grant 714591 VirBA-cous. Niels Aage acknowledges the support of the Villum Foundation as part of the InnoTop project. (STMicroelectronics, Switzerland|081/16CR, ERC|714591, Villum Foundation)status: Publishe
Guglielmo Giannini e il teatro agitprop liberale
No full textF. Perrelli, Guglielmo Giannini and the Liberal Agitprop Theatre
This essay through the analysis of Il ragionier Ventura (1947) demonstrates how Guglielmo Giannini’s dramaturgy could construct an unusual model of liberal agitprop play, absolutely unique in the panorama of twentieth-century political theatre
SCIENZA E FILOSOFIA: PER UN LINGUAGGIO COMUNE NEL TERZO MILLENNIO
No full textThe foundation (or refoundation) of a flexible and multifunctional Lògos for shaping a common language should be the main object of an ambitious project for the third millennium. We urge to imagine a platform in which science and philosophy are complicated. We need to construe a heuristic scaffolding to think in new ways an allegiance in which science and philosophy can find a new intimacy. In this interview Lucio Pastore and Gianluca Giannini discuss some crucial themes on the frontier between philosophical investigation and scientific innovations (with particular regard to life sciences)
An approach to harmonic load- and source-pull measurements for high-efficiency PA design
No full textHigh-efficiency power-amplifier design requires numerous efforts to investigate both input and output harmonic terminations effects. A simplified theoretical approach to clarify the relevance of such terminations is presented here, and design criteria to improve efficiency for high-frequency applications are briefly discussed. An advanced active load/source-pull test-bench has been used to validate theoretical harmonic tuning techniques, characterizing an active device. The adopted optimization strategy is presented, together with measured results obtained with a medium-power 1-mm MESFET at 1 GHz. Input second harmonic impedances effects are stressed, showing a drain efficiency spread between 37%-49% for a fixed input power level, corresponding to 1-dB compression. Finally, as predicted by the presented theory, after input second harmonic tuning, further improvements are obtained, increasing fundamental output load resistive part, demonstrating an additional drain efficiency enhancement, which reaches a level of 55% at 1-dB compression
Europa, idea di umanità e visione della storia in Karl Jaspers
No full textNella prospettiva filosofica di Karl Jaspers appare centrale la sua visione della storia, nel suo nesso dinamico tra dimensione individuale e tensione universale. Strettamente congiunta alla visione della storia appare le nozioni di Europa e di umanità (fortemente collegate alla centralità della libertà), decisive ai fini non solo del passato ma del futuro stess
On the class-F power amplifier design
No full textPower-amplifier class-F operation is investigated and revised, evidencing the fundamental importance of the harmonic-generating mechanism and the limitations imposed by the device input and output nonlinearities on the ideal class-F behavior. Closed-form expressions are derived for the major design quantities, together with the optimum fundamental and third-harmonic loading of the active device. A design procedure, making use of the derived expressions, is presented and the deviations from the ideal behavior are discussed. Sample designs, making use of a fall nonlinear device model and commercial analysis software, are carried out to demonstrate the effectiveness of the analysis and the design procedure. It is shown, both analytically and using commercial nonlinear simulations, that blind application of commonly used, idealized class-F harmonic terminations can cause unexpected detrimental results. (C) 1999 John Wiley & Sons, Inc
Il parlato dei mass media: analisi multilingue del parlato dei telegiornali
No full textThe results of experimental surveys carried out on a corpus of spoken Italian on
both radio and television show unequivocally that the rhythmic-prosodic
characteristics of the speech used on radio and television news programmes have
changed radically over the past fifty years. Several studies show certain marked
changes that indicate a well-defined direction. It must be pointed out that the
changes involved do not relate to the text of the utterance, but to the way it is
delivered (articulation rate, speech rate, fluency, silence percentage and tonal
range). Do the rhythmic/prosodic changes relate only to Italian, or, because of mass
means of communication, are they true of other languages? Do different language
systems share the same model of rhythmic/prosodic patterns? Can we be said to be
approaching a global type of speech? The results of this experimental research
carried out on television information speech in Italian, English, French, Slovenian
and Japanese show a surprising parallelism in the development of these languages.
In fact, the television news speech of the 1960‟s and up to the mid-1970‟s, compared
with television news today, shows less speech rate, longer pauses, a lower level of
fluency, an intonation trend which is less varied, and minimum differences in rate of
articulation. In particular, the data reveal that recent television news, in all the
languages analysed, are characterised by a drastic diminishing of the percentage of
silence as compared to past ones. Fluency too, though in a different way, shows a
net increase in today‟s television news. Another interesting fact common to all the
television news broadcasts is the stability of the articulation rate. The fact is that the
television news is read by professionals, the articulation positioning must be
precise, the target audiences must be reached and the speaker must be clear and
unambiguous
Theory and experimental results of a class F AB-C doherty power amplifier
No full textThe aim of this paper is to present a closed-form formulation suitable for a direct computer-aided design synthesis of a Doherty amplifier employing a Class F design strategy for the Main (or Carrier) device. For this purpose, starting from a simplified model for the adopted active devices, the behavioral analysis of the Class F Doherty amplifier is carried out as a function of the input signal. A particular emphasis is dedicated to put into evidence the differences existing when a simple tuned load harmonic termination is considered. The theoretical aspects are deeply discussed and an experimental validation is also provided
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