Wealth distribution in presence of debts. A Fokker--Planck description

We consider here a Fokker--Planck equation with variable coefficient of diffusion which appears in the modeling of the wealth distribution in a multi-agent society. At difference with previous studies, to describe a society in which agents can have debts, we allow the wealth variable to be negative. It is shown that, even starting with debts, if the initial mean wealth is assumed positive, the solution of the Fokker--Planck equation is such that debts are absorbed in time, and a unique equilibrium density located in the positive part of the real axis will be reached

Condensation phenomena in nonlinear drift equations

We study nonnegative, measure-valued solutions to nonlinear drift type equations modelling concentration phenomena related to Bose-Einstein particles. In one spatial dimension, we prove existence and uniqueness for measure solutions. Moreover, we prove that all solutions blow up in finite time leading to a concentration of mass only at the origin, and the concentrated mass absorbs increasingly the mass converging to the total mass as time goes to infinity. Our analysis makes a substantial use of independent variable scalings and pseudo-inverse functions techniques

Acquired ptosis associated with oculomotor and contralateral facial nerve synkinesis: the first reported case

Evidence of oculomotor nerve (ON) synkinesis is a common occurrence following both acquired and congenital III nerve palsy. It is generally accepted that aberrant regeneration is the likely aetiology of synkinesis in acquired III nerve palsy, following intracranial aneurysm, trauma, compressive neoplasms, cavernous sinus thrombosis and basilar meningitis

The Equivalence of Fourier-based and Wasserstein Metrics on Imaging Problems

We investigate properties of some extensions of a class of Fourier-based probability metrics, originally introduced to study convergence to equilibrium for the solution to the spatially homogeneous Boltzmann equation. At difference with the original one, the new Fourier-based metrics are well-defined also for probability distributions with different centers of mass, and for discrete probability measures supported over a regular grid. Among other properties, it is shown that, in the discrete setting, these new Fourier-based metrics are equivalent either to the Euclidean-Wasserstein distance $W_2$, or to the Kantorovich-Wasserstein distance $W_1$, with explicit constants of equivalence. Numerical results then show that in benchmark problems of image processing, Fourier metrics provide a better runtime with respect to Wasserstein ones.Comment: 18 pages, 2 figures, 1 tabl

Partial Discharges in Electrical Machines for the More Electric Aircraft—Part I: A Comprehensive Modeling Tool for the Characterization of Electric Drives Based on Fast Switching Semiconductors

This paper proposed a modelling approach for the comprehensive analysis of high-frequency challenges in electrical drives designed for aerospace applications, in particular the overvoltage at the machine terminals and the voltage distribution within windings. After a separate description of the models for the estimation of these insulation stress sources, the combined model was detailed. The main benefit of developing a combined, flexible and comprehensive tool is that both overvoltage at machine terminals and uneven voltage distribution can be calculated simultaneously, without neglecting the voltage overshoot when estimating the voltage distribution (and vice versa). In fact, an accurate calculation of the terminal overvoltage is necessary to provide a good estimation of the voltage within winding turns since its waveform shape can be quite different with respect to the converter output, even with cables of a few meters. A case study based on a real aerospace application was considered to investigate the model validity and accuracy. Experimental results were performed on a complete system comprising a SiC-based converter, a connecting cable and a machine stator, proving the simulation model accuracy in terms of peak voltages of both the line-to-line terminal voltage and the turn voltage distribution across the first turns, which are the most relevant quantities for the sake of this study as well as for the investigations of the subsequent companion papers. In the forthcoming papers, the effects of different rise times and cable lengths on the inception of partial discharges will be investigated through fast parametric simulation carried out using the proposed combined model. The feasibility of using conventional insulation systems for aircraft applications using SiC drives fed by a ±270 V DC bus voltage will be discussed, with the aim of signaling and finding solutions to improve the overall reliability

Improving Harmonic Measurements with Instrument Transformers: a Comparison Among Two Techniques

The measurement of harmonics is essential in modern power systems in order to perform distortion level assessment, disturbances source detection and mitigation, etc. In this context, the role of Instrument Transformers (ITs) is crucial, as they are key elements in every power systems measuring instrument. However, inductive ITs, which are still the most widely used, suffer from both a filtering behavior due to their dynamics and from nonlinear effects due to their iron core. The target of this paper is to deeply analyze the performance of two digital signal processing techniques, recently proposed in literature, aimed at mitigating their nonlinear behavior: they are SINDICOMP and the compensation of harmonic distortion through polynomial modeling in the frequency domain. Their performance in improving the measurement of voltage harmonics are analyzed through numerical simulations, by adopting waveforms that can be typically encountered in power systems during normal operating conditions

Intermediate asymptotics beyond homogeneity and self-similarity: long time behavior for [formula]

"Vegeu el resum a l'inici del document del fitxer adjunt"

Structural elements made with highly flowable UHPFRC: Correlating computational fluid dynamics (CFD) predictions and non-destructive survey of fiber dispersion with failure modes

Structural design with highly flowable Fibre Reinforced Concrete has to duly take into account the preferential alignment of fibers, which can be governed through the rheological properties of the fluid mixture and the casting process and by the geometry of the structure. The possibility of predicting the fiber alignment, by tailoring the casting process, and of non-destructively monitoring it, can foster more efficient structural applications and design approaches. Focusing on UHPFRC slabs with pre-arranged casting defects, the flow-induced alignment of the fibers has been predicted by means of a suitable CFD modelling approach and hence monitored via a non-destructive method based on magnetic inductance properties of the fiber reinforced composite. The comparison between the assessed data on the fiber orientation and the crack patterns as visualized by image analysis supports the effectiveness of casting flow modelling and non-destructive fiber dispersion monitoring in supporting the structural design of elements made with highly flowable fiber reinforced cementitious composites

Transducer Arrays Over A²B Networks in Industrial and Automotive Applications: Clock Propagation Measurements

Advanced automotive applications like Active Noise Cancellation (ANC) and Individual Listening Zones (ILZ) require a high number of transducers (i.e., microphones, accelerometers, and loudspeakers) usually arranged as arrays. Transducer arrays are widely employed in several applications besides automotive field, such as teleconferencing systems, industrial and civil monitoring of noise and vibrations. Automotive Audio Bus ( $\text{A}^{2}\text{B}$ ) is an audio transport protocol that solves the latest requirements of automotive and industrial fields. $\text{A}^{2}\text{B}$ allows transporting up to 32 channels in a multi-node daisy chain network and guarantees synchronization and low deterministic latency. This paper aims to develop a clock propagation model of an $\text{A}^{2}\text{B}$ network composed by transducer arrays. This model will be useful to evaluate the impact of the bus on the array performance. Firstly, a theoretical description of the $\text{A}^{2}\text{B}$ protocol and jitter analysis is provided. It follows a description of the jitter measures carried out on the clocks distributed along the $\text{A}^{2}\text{B}$ network. Lastly, latency introduced by nodes of the network is investigated

Biocontrol of Penicillium nordicum Growth and Ochratoxin A Production by Native Yeasts of Dry Cured Ham

Twelve yeast strains isolated from the surface of Italian typical dry-cured hams, belonging to D. hansenii, D. maramus, C. famata, C. zeylanoides and H. burtonii species, and previously selected for their ability to grow in dry-cured ham-like substrates, were screened for antagonistic activity against a toxigenic strain of P. nordicum and inhibition of ochratoxin A (OTA) biosynthesis. On average, yeast inhibitory activity was lowered by increasing fungal inoculum and enhanced by NaCl presence. In the assay conditions, H. burtonii and C. zeylanoides were the most effective, both in inhibiting P. nordicum growth and OTA production. D. hansenii was the species with the lowest inhibitory activity, especially in the absence of salt. OTA production dropped from the range < LOD − 5000 ppb in P. nordicum control plates to the range < LOD − 200 ppb in yeast-added plates. OTA production increased in the presence of NaCl in P. nordicum control plates, while salt enhanced inhibition against OTA production in yeast-added plates