Design of a Low-Power VLSI Macrocell for Nonlinear Adaptive Video Noise Reduction

A VLSI macrocell for edge-preserving video noise reduction is proposed in the paper. It is based on a nonlinear rational filter enhanced by a noise estimator for blind and dynamic adaptation of the filtering parameters to the input signal statistics. The VLSI filter features a modular architecture allowing the extension of both mask size and filtering directions. Both spatial and spatiotemporal algorithms are supported. Simulation results with monochrome test videos prove its efficiency for many noise distributions with PSNR improvements up to 3.8 dB with respect to a nonadaptive solution. The VLSI macrocell has been realized in a 0.18 m CMOS technology using a standard-cells library; it allows for real-time processing of main video formats, up to 30 fps (frames per second) 4CIF, with a power consumption in the order of few mW

TRPA1 mediates aromatase inhibitor-evoked pain by the aromatase substrate androstenedione

Aromatase inhibitors (AI) induce painful musculoskeletal symptoms (AIMSS), which are dependent upon the pain transducing receptor TRPA1. However, as the AI concentrations required to engage TRPA1 in mice are higher than those found in the plasma of patients, we hypothesized that additional factors may cooperate to induce AIMSS. Here we report that the aromatase substrate androstenedione, unique among several steroid hormones, targeted TRPA1 in peptidergic primary sensory neurons in rodent and human cells expressing the native or recombinant channel. Androstenedione dramatically lowered the concentration of letrozole required to engage TRPA1. Notably, addition of a minimal dose of androstenedione to physiologically ineffective doses of letrozole and oxidative stress byproducts produces AIMSS-like behaviors and neurogenic inflammatory responses in mice. Elevated androstenedione levels cooperated with low letrozole concentrations and inflammatory mediators were sufficient to provoke AIMSS-like behaviors. The generation of such painful conditions by small quantities of simultaneously administered TRPA1 agonists justifies previous failure to identify a precise link between AIs and AIMSS, underscoring the potential of channel antagonists to treat AIMSS

Closed Loop Electronic Fuel Injection for S.I. Engines

A new self-adaptive electronic injection system is presented. Both the theory of operation and the development of an experimental prototype are discussed in detail. Finally, experimental results are reported to demonstrate the validity of the system

Sistema di iniezione elettronica per motori ad A.C. con controllo del rapporto di miscela per retroazione

Vengono illustrati sia le caratteristiche realizzative che i risultati sperimentalii relativi ad un sistema di iniezione elettronica per motori ad accensione comandata, caratterizzato dal controllo del rapporto combustibile-aria mediante retroazìone e viene mostrata una particolare versione della strategia di controllo. Essendo la ricerca focalizzata soprattutto sul dispositivo di retroazione, per semplicità si è preferito, anziché costruire ex-novo l’intero apparato di iniezione, basarsi su quello montato all’origine sul motore FIAT 132/2000 utilizzato per la sperimentazione. Tale apparato, opportunamente modificato, è stato interfacciato con un microprocessore che effettua i calcoli necessari per ottenere il controllo voluto. I risultati sperimentali riguardano sia il funzionamento del motore, sia quello del sistema elettronico

Sistema di iniezione elettronica per motori ad accensione comandata

Il presente trovato si riferisce ad un sistema di iniezione elettronica per motori ad accensione comandata, il quale è caratterizzato dal fatto che il rapporto combustibile-aria viene regolato mediante retroazione al fine di ottenere il massimo rendimento in ogni condizione di funzionamento del motore o la massima potenza ad ogni regime di rotazione dello stesso

Metodo per ottimizzare il rapporto combustibile-aria mediante retroazione, su motori ad iniezione elettronica ed A.C.

In questo lavoro vengono presentati i risultati degli studi fin qui condotti nell’ambito di una ricerca, che ha per obiettivo la realizzazione di un sistema dì iniezione elettronica per motori ad accensione comandata, caratterizzato dalla correzione continua, mediante retroazione, del rapporto combustibile-aria, al fine di ottimizzare il rendimento o la potenza. In particolare viene illustrato il metodo di ottimizzazione scelto e viene descritto il sistema elettronico, già realizzato sotto forma di prototipo sperimentale, che ne esegue l’algoritmo di calcolo

Mixed-signal design of a digital input power amplifier for automotive audio applications

With reference to digital input power amplifier for automotive audio applications, the paper presents an exhaustive exploration of the huge mixed-signal space to find optimal trade-offs among different cost-junctions: distortion, efficiency, circuit complexity and sensitivity. Different architectural solutions are modelled and compared in a Simulink/Spice framework. All building blocks (i.e. oversampling filter, noise shaping, type of PWM modulation, type of feedback, power stage, LC filter) are optimized considering the whole system performance. A novel mixed-signal scheme is finally derived and prototyped

Mixed-Signal Architectures for High-Efficiency and Low-Distortion Digital Audio Processing and Power Amplification

The paper addresses the algorithmic and architectural design of digital input power audio amplifiers. A modelling platform, based on a meet-in-the-middle approach between top-down and bottom-up design strategies, allows a fast but still accurate exploration of the mixed-signal design space. Different amplifier architectures are configured and compared to find optimal trade-offs among different cost-functions: low distortion, high efficiency, low circuit complexity and low sensitivity to parameter changes. A novel amplifier architecture is derived; its prototype implements digital processing IP macrocells (oversampler, interpolating filter, PWM cross-point deriver, noise shaper, multilevel PWM modulator, dead time compensator) on a single low-complexity FPGA while off-chip components are used only for the power output stage (LC filter and power MOS bridge); no heatsink is required. The resulting digital input amplifier features a power efficiency higher than 90% and a total harmonic distortion down to 0.13% at power levels of tens of Watts. Discussions towards the full-silicon integration of the mixed-signal amplifier in embedded devices, using BCD technology and targeting power levels of few Watts, are also reported