Ultrasonic motors have been exploited mainly in low power and low duty cycle applications. In aerospace and automotive applications, there is also the need for motors able to provide high torque but ...employed at very low duty cycle. In this work numerical simulations and experimental measurements carried out on a high power ultrasonic motor are presented. The proposed motor is composed of a annular shaped stator and two light cone shaped rotors. The rotors are pressed in contact to the borders of the inner surface of the stator by means of an opportune pre-stress system. A travelling rotating wave is generated in the stator by two and four Bolted Langevin Transducers, opportunely placed on the lateral surface of the stator. Each transducer is designed to excite in the ring radial nonaxisymmetric modes. The effective generation of the travelling wave in the stator, with both two and four driving transducers, has been accurately simulated with a FEM software. A prototype of the motor has been constructed and experimentally characterized. Comparisons between simulation and measurements have shown a satisfactory agreement. The improvement of motor performances achieved by increasing the number of driving transducers is analyzed and discussed.
We treat an inverse electrical conductivity problem which deals with the reconstruction of nonlinear electrical conductivity starting from boundary measurements in steady currents operations. In this ...framework, a key role is played by the Monotonicity Principle, which establishes a monotonic relation connecting the unknown material property to the (measured) Dirichlet-to-Neumann operator (DtN). Monotonicity Principles are the foundation for a class of non-iterative and real-time imaging methods and algorithms. In this article, we prove that the Monotonicity Principle for the Dirichlet Energy in nonlinear problems holds under mild assumptions. Then, we show that apart from linear and \(p\)-Laplacian cases, it is impossible to transfer this Monotonicity result from the Dirichlet Energy to the DtN operator. To overcome this issue, we introduce a new boundary operator, identified as an Average DtN operator.
Success and pitfall of anticlotting therapy Fiori, Patrizia; Allegorico, Lia; Capaldo, Guglielmo ...
Journal of the neurological sciences,
October 2021, 2021-10-00, Letnik:
429
Journal Article
Wrong or right decision making? Fiori, Patrizia; Allegorico, Lia; Capaldo, Guglielmo ...
Journal of the neurological sciences,
October 2021, 2021-10-00, Letnik:
429
Journal Article
Abstract Inverse problems, which are related to Maxwell’s equations, in the presence of nonlinear materials is a quite new topic in the literature. The lack of contributions in this area can be ...ascribed to the significant challenges that such problems pose. Retrieving the spatial behavior of some unknown physical property, from boundary measurements, is a nonlinear and highly ill-posed problem even in the presence of linear materials. Furthermore, this complexity grows exponentially in the presence of nonlinear materials. In the tomography of linear materials, the Monotonicity Principle (MP) is the foundation of a class of non-iterative algorithms able to guarantee excellent performances and compatibility with real-time applications. Recently, the MP has been extended to nonlinear materials under very general assumptions. Starting from the theoretical background for this extension, we develop a first real-time inversion method for the inverse obstacle problem in the presence of nonlinear materials. The proposed method is intendend for all problems governed by the quasilinear Laplace equation, i.e. static problems involving nonlinear materials. In this paper, we provide some preliminary results which give the foundation of our method and some extended numerical examples.
Neuron specific enolase in a SARS CoV2 patient Fiori, Patrizia; Allegorico, Lia; Capaldo, Guglielmo ...
Journal of the neurological sciences,
October 2021, 2021-10-00, 20211001, Letnik:
429
Journal Article
Abstract
We treat an inverse electrical conductivity problem which deals with the reconstruction of nonlinear electrical conductivity starting from boundary measurements in steady currents ...operations. In this framework, a key role is played by the Monotonicity Principle, which establishes a monotonic relation connecting the unknown material property to the (measured) Dirichlet-to-Neumann operator (DtN). Monotonicity Principles are the foundation for a class of non-iterative and real-time imaging methods and algorithms. In this article, we prove that the monotonicity principle for the Dirichlet Energy in nonlinear problems holds under mild assumptions. Then, we show that apart from linear and
p
-Laplacian cases, it is impossible to transfer this monotonicity result from the Dirichlet Energy to the DtN operator. To overcome this issue, we introduce a new boundary operator, identified as an average DtN operator.
Binomial Measures and their Approximations Calabrò, Francesco; Esposito, Antonio Corbo; Perugia, Carmen
Real analysis exchange,
01/2011, Letnik:
37, Številka:
1
Journal Article
Recenzirano
In this paper we consider the properties of a family of probability (continuous and singular) measures, which will be called Binomial measures because of their relationship with the binomial model in ...probability. These measures arise in many applications with different notations. Many properties in common with Lebesgue measure hold true for this family, sometimes unexpectedly. PUBLICATION ABSTRACT
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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