MV-algebras freely generated by finite Kleene algebras

If V and W are varieties of algebras such that any V-algebra A has a reduct U(A) in W, there is a forgetful functor U: V->W that acts by A |-> U(A) on objects, and identically on homomorphisms. This functor U always has a left adjoint F: W->V by general considerations. One calls F(B) the V-algebra freely generated by the W-algebra B. Two problems arise naturally in this broad setting. The description problem is to describe the structure of the V-algebra F(B) as explicitly as possible in terms of the structure of the W-algebra B. The recognition problem is to find conditions on the structure of a given V-algebra A that are necessary and sufficient for the existence of a W-algebra B such that F(B) is isomorphic to A. Building on and extending previous work on MV-algebras freely generated by finite distributive lattices, in this paper we provide solutions to the description and recognition problems in case V is the variety of MV-algebras, W is the variety of Kleene algebras, and B is finitely generated--equivalently, finite. The proofs rely heavily on the Davey-Werner natural duality for Kleene algebras, on the representation of finitely presented MV-algebras by compact rational polyhedra, and on the theory of bases of MV-algebras.Comment: 27 pages, 8 figures. Submitted to Algebra Universali

Microwave Active Filter Design

A simplified method for the project and design of microwave active filters is presented here. The presented design is based on the use of an active inductor that emulates an inductor behavior by implementing a passive variable phase- and amplitude-compensating network and amplifiers, forming a gyrator-C architecture. This method can be applied with success for the design of bandpass filters with very high performances in terms of integration and application from a few hundreds of MHz to tens of GHs with filter high dynamic range and frequency tuning capability

An IC architecture for RF Energy Harvesting systems

In this work we present an IC architecture for RF energy harvesting. The system has been designed with a 0.18μm CMOS SMIC technology and optimized at 900MHz. Simulation results have confirmed that the integrated system handles an incoming power typically ranging from -25 dBm to 20 dBm by rectifying the variable input signals into a DC voltage source with an overall efficiency up to 50%. The chip area estimation for the proposed system is as low as 3x3mm2

A GPU based multidimensional amplitude analysis to search for tetraquark candidates

The demand for computational resources is steadily increasing in experimental high energy physics as the current collider experiments continue to accumulate huge amounts of data and physicists indulge in more complex and ambitious analysis strategies. This is especially true in the fields of hadron spectroscopy and flavour physics where the analyses often depend on complex multidimensional unbinned maximum-likelihood fits, with several dozens of free parameters, with an aim to study the internal structure of hadrons. Graphics processing units (GPUs) represent one of the most sophisticated and versatile parallel computing architectures that are becoming popular toolkits for high energy physicists to meet their computational demands. GooFit is an upcoming open-source tool interfacing ROOT/RooFit to the CUDA platform on NVIDIA GPUs that acts as a bridge between the MINUIT minimization algorithm and a parallel processor, allowing probability density functions to be estimated on multiple cores simultaneously. In this article, a full-fledged amplitude analysis framework developed using GooFit is tested for its speed and reliability. The four-dimensional fitter framework, one of the firsts of its kind to be built on GooFit, is geared towards the search for exotic tetraquark states in the $B^0 \rightarrow J/\psi K \pi$ decays and can also be seamlessly adapted for other similar analyses. The GooFit fitter, running on GPUs, shows a remarkable improvement in the computing speed compared to a ROOT/RooFit implementation of the same analysis running on multi-core CPU clusters. Furthermore, it shows sensitivity to components with small contributions to the overall fit. It has the potential to be a powerful tool for sensitive and computationally intensive physics analyses.Comment: Replaced with the published version. Added the journal reference and the DO

Enhancing selectivity in photocatalytic formation of p-anisaldehyde in aqueous suspension under solar light irradiation via TiO2 N-doping

The photocatalytic partial oxidation of 4-methoxybenzyl alcohol to the corresponding aldehyde (p-anisaldehyde) was performed under simulated solar irradiation by using home prepared N-doped TiO2 catalysts. The photocatalysts were prepared by a sol–gel method, using TiCl4 as TiO2 precursor and NH4Cl, urea or NH4OH as N-doping sources. A commercial TiO2 (Degussa P25) was also used for comparison aims. The prepared catalysts were characterized by BET specific surface area, XRD, ESEM and UV-vis spectroscopy. The reactivity results show that (i) the doped catalysts are predominantly amorphous, and they show selectivity values far higher than those of the corresponding undoped ones and of well crystallized catalysts – even if the last ones show a higher activity – and (ii) exploitation of solar light significantly increases the reaction selectivity. In addition, different light sources were also used in order to investigate the effect of radiation wavelength ranges on the reactivity and selectivity to aldehyde

Electronic Interface for Lidar System and Smart Cities Applications

This work deals with the design of a new readoutelectronics for silicon photomultipliers sensors. The so-calledSiPMs sensors are an emerging technology currentlydiffusing in many applications and, among them, in thedefinition of a new generation of LIDAR systems. Thelatter, nowadays have a primary role in the evolutionprocess that is involving Smart Cities, being an enablingtechnology in different fields. The solution here proposed isrealized at electronic level with a 150 nm technology processfrom LFoundry and results provide a feasibledemonstration of the capability of the proposed designapproach to be employed in practical application

Noise analysis and optimization of VCII-based SiPM interface circuit

AbstractRecently, second generation voltage conveyor (VCII)-based transimpedance amplifiers (TIAs) have begun to find their way in different applications, among which, silicon photomultipliers (SiPMs) interfacing circuitry. There are many advantages which make VCII-based TIAs attractive over conventional circuits: the intrinsic low impedance at VCII current input Y port is very helpful to mitigate the effect of high value sensor capacitance and provides fast response time; the achieved bandwidth is high and due to current mode operation; the circuits enjoy the low-voltage low-power features. As signal-to-noise ratio is a crucial parameter in SiPMs interface circuit applications, here we consider the noise specifications and optimization of VCII-based SiPM interface circuits. The noise model of VCII is introduced and equivalent noise of a VCII-based interface circuit is derived. Methods to optimize trade-offs existing between key parameters including power consumption, gain and noise performance are discussed. Simulation results are also provided showing a considerable reduction of two orders of magnitude in most of the noise performances when compared to the previous work while preserving other performance parameters

Advanced Computational Methods for Oncological Image Analysis.

The Special Issue "Advanced Computational Methods for Oncological Image Analysis", published for the Journal of Imaging, covered original research papers about state-of-the-art and novel algorithms and methodologies, as well as applications of computational methods for oncological image analysis, ranging from radiogenomics to deep learning [...]