Papers by Ermanno Di Zitti
An Optimized AC/DC Buck-Boost Converter for Wind Energy Harvesting Application
2019 IEEE International Conference on Environment and Electrical Engineering and 2019 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe), 2019
The need for low cost power sources was always the scope of researchers, especially for applicati... more The need for low cost power sources was always the scope of researchers, especially for applications such as Wireless sensor networks (WSN), where the maintenance and replacement of energy storage units is costly. In this sense, energy harvesting (EH) is more reliable and cheaper due to its unlimited availability. Though, the environment conditions are usually unpredictable, which requires a specialized circuit to be used with the energy harvesters to ensure the efficient power transfer and to adapt to the variable conditions. The proposed system is a specialized EH circuit for the fluttering wind harvester. It consists of an AC/DC buck-boost converter, controlled by a low power microcontroller which adapts the performance according the variable wind conditions, giving an edge over commercial circuits for the same purpose.
Langmuir-Blodgett films of pyrrole derivatives: electrical characterization by microelectronic test structures for sensor applications
Film di Langmuir-Blodgett di Poli-Alchil-Pirroli per Sensori e Dispositivi Molecolari
Characterization of a cellular array of dipoles for molecular information processing
AIP Conference Proceedings, 1992
ABSTRACT A physical system consisting of a lipid monolayer surrounded by a set of electrodes is d... more ABSTRACT A physical system consisting of a lipid monolayer surrounded by a set of electrodes is defined and proposed as a plausible example of a molecular circuit for information processing. The lipid monolayer is characterized as a cellular array of electric dipoles, where each dipole lying on the monolayer plane represents the head of a lipid molecule. Each dipole experiences the effects of the electric field generated by both the surrounding dipoles and the electrodes. The electrodes' contribution to the electric field is calculated through a proper discretization of their charge densities. According to this model the dipoles of the cellular array play the role of neurodes whose state is described by the dipole orientations on the plane, and a cellular automation can be defined once the orientation values have been properly discretized. The electrodes act as input- and output-signal sources. it is shown that the simple system considered here, i.e., a two-port system, is characterized by a nonlinear voltage transfer curve, with a switching threshold associated with a state transition of the cellular array. These results can be considered as a first step toward of more realistic structures useful in information processing, e.g., molecular cellular automata and neutral networks.
Simulating neural networks on concurrent architectures
International Journal of Radiation Applications and Instrumentation. Part C. Radiation Physics and Chemistry, 1988
Recombmnatlon centers introduced by irradiation with 12 MeV electrons In large area silicon dlode... more Recombmnatlon centers introduced by irradiation with 12 MeV electrons In large area silicon dlodes with p-l-n structure are studied with the Deep Level Transient Spectroscopy technique KEYWORDS Semiconductor diode, electron-induced defects~ defect levels, defect annealing, electron irradiation, capture cross-sectlon, recovered charge, recovery time, forward voltage drop.
SPM Investigation of Thiolated Gold Nanoparticle Patterns Deposited on Different Self-Assembled Substrates
NATO Science Series II: Mathematics, Physics and Chemistry, 2005
We present the results of a Scanning Probe Microscopy (SPM) investigation of ordered nanosized me... more We present the results of a Scanning Probe Microscopy (SPM) investigation of ordered nanosized metallo-organic structures. Our aim is to investigate the organization and stability of thiolated gold nanoparticles in a compact pattern when deposited onto gold substrates functionalized with self-assembled monolayers made from two molecules that differ essentially in their terminating group: 1,4-benzenedimethanethiol and 4-methylbenzylthiol. The dodecanethiol capped gold-nanoparticles
Physica E: Low-dimensional Systems and Nanostructures, 2008
The ability to control the spatial arrangement of molecular nanocrystals is of fundamental import... more The ability to control the spatial arrangement of molecular nanocrystals is of fundamental importance for the fabrication of nanoscale devices. In this work, we report on experimental procedures to control the formation of 50 nm, organically capped, gold nanoparticles by tuning the deposition conditions. We found the parameters which lead to the formation of different domain structures, from threedimensional aggregates to two-dimensional structures, to even isolated particles.
Efficient emulation of neural networks on concurrent architectures for optimization problems
IEEE International Symposium on Circuits and Systems
ABSTRACT Specific optimization problems can be solved with high efficiency by neural network mode... more ABSTRACT Specific optimization problems can be solved with high efficiency by neural network models, due to their intrinsic massive parallelism. The emulation of neural algorithms on concurrent architectures can preserve their computational power. The authors illustrate and discuss the implementation of Hopfield networks for the solution of the traveling salesman problem on 2-D meshes of transputers. The investigations are concentrated both on the computational efficiency and on the quality of solutions (global-local minima issue)
Assembly of carbon nanotubes onto arrays of microfabricated test patterns for the design of nanoelectronic devices
4th IEEE Conference on Nanotechnology, 2004.
This paper addresses some key issues to look over an efficient strategy to integrate carbon nanot... more This paper addresses some key issues to look over an efficient strategy to integrate carbon nanotube devices in electronic structures. Proper microfabricated test patterns have been designed to deposit in a controlled way single wall nanotube ropes between different couples of source and drain electrodes, providing a common back gate for current modulation. Nanotubes have been fabricated by the laser
Mapping linear algebra algorithms into array processors: a case study
ICASSP-88., International Conference on Acoustics, Speech, and Signal Processing
ABSTRACT A general methodology, based on the concept of folding, for mapping wavefront algorithms... more ABSTRACT A general methodology, based on the concept of folding, for mapping wavefront algorithms into processor square meshes of fixed size has been implemented on a mesh of INMOS transputers, programmed in OCCAM, for the multiplication of matrices of arbitrary size. Different implementations of the code are considered and compared. The computational costs are analyzed in detail. The method and the performances of the system used are compared with other more standard solutions
A method for programming matrix algorithms in array processors
[Proceedings] COMPEURO 88 - System Design: Concepts, Methods and Tools
ABSTRACT A method for mapping uniformly distributed (wavefront like) algorithms into processor sq... more ABSTRACT A method for mapping uniformly distributed (wavefront like) algorithms into processor square meshes of fixed size, which is based on the concept of folding, is applied to matrix computation (matrix multiplication and LU decomposition). Array processors programmed in Occam are considered. The programming methodology, which can be automated, is analyzed in detail
A linear rotation based solution of large systems on a transputer array
Microprocessors and Microsystems, 1995
ABSTRACT The concurrent solution of large linear systems of equations on processor meshes of fixe... more ABSTRACT The concurrent solution of large linear systems of equations on processor meshes of fixed size has been considered taking into account the basic requirements of computational efficiency and stability. A linear rotation based algorithm has been studied as a robust solution of linear problems well suited to be implemented on parallel architectures because of its regular computational structure. The exploitation of the intrinsic parallelism of the algorithm and the application of partitioning techniques have addressed a locally parallel globally sequential parallelization strategy. The method has been experimentally evaluated on different sized arrays of transputers, demonstrating that high computational efficiency can be achieved.
A behavioural simulator and its use for the validation of hypercube architectures
Microprocessing and Microprogramming, 1988
ABSTRACT The synthesis of software algorithms and their hardware implementation require the use o... more ABSTRACT The synthesis of software algorithms and their hardware implementation require the use of efficient CAD tools providing detailed simulations and performance analysis. This paper presents a new behavioural simulator whose functional model is characterized by strict and non-strict functions, and by the concept of static and dynamic instances defined at different hierarchical levels of the structural description. Then, an extensive application of the simulator for the study of hypercube architectures is described.
High efficiency solution of triangular system equations on a 2-D array of transputers
Microprocessing and Microprogramming, 1989
ABSTRACT A method, based on the concept of folding, for partitioning wavefront algorithms on 2-D ... more ABSTRACT A method, based on the concept of folding, for partitioning wavefront algorithms on 2-D meshes of Transputers of fixed size, has been applied to the solution of triangular system equations. When the size of the matrix is much larger than the size of the mesh of processors, high efficiency (η ≧ 0.7) is achieved independently of the number of processors (linear speed-up).
IEE Proceedings G Circuits, Devices and Systems, 1990
A functional/behavioural simulator is described, in which the system to be simulated is modelled ... more A functional/behavioural simulator is described, in which the system to be simulated is modelled by defining its hierarchy and by specifying the descriptive function of the behaviour of its components. The functional model, based on the definition of strict and nonstrictfunctions, makes it possible to introduce and formally justify a simulation mechanism for safe sequencing of concurrent events in the presence of zero-delay components. Static and dynamic component instances are allowed, and the system can be simulated at different hierarchical levels, specified by the user for each component. The simulation algorithm is based on an event-driven mechanism and has been implemented in the language C.
Size variation of nickel nanocrystals passivated with alkyl amines on thermolytic reduction
We report the size control of nickel nanoparticles (NiNPs) through thermolytic reduction. The NiN... more We report the size control of nickel nanoparticles (NiNPs) through thermolytic reduction. The NiNP size was found to be varying from mono to bimodal distribution as a function of the reaction temperature and time with a narrow size distribution of 2 to 20 nm. The NiNP size and shape have been followed by employing two different lipophilic alkaylamine ligands either
Scanning tunneling microscopy imaging of organic layers on graphite
Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1992
Organic monolayers of dotriacontane and tetracosanoic acid physisorbed on graphite have been stud... more Organic monolayers of dotriacontane and tetracosanoic acid physisorbed on graphite have been studied by scanning tunneling microscopy at the liquid-solid interface. A high degree of two-dimensional ordering appeared for both the organic compounds observed : the molecules were arranged on graphite in stripelike lamellae of various shape and length. Experimental conditions for high contrast imaging are discussed.
Ultra short pulse propagation modeling in nonlinear dispersive GaAs structures addressing the finite difference time domain simulation method
AIP Conference Proceedings, 2012
ABSTRACT The ultra-short pulse propagation in Gallium Arsenide (GaAs) structures can be modeled t... more ABSTRACT The ultra-short pulse propagation in Gallium Arsenide (GaAs) structures can be modeled through the Piecewise Linear Recursive Convolution (PLRC) technique in the context of the Finite-Difference Time-Domain (FDTD) solution of Maxwell's equations. Our model is based on a Lorentzian formulation of dispersive media, taking into account the Raman, Kerr and Two-Photon Absorption nonlinearities. Soliton propagation in the presence of nonresonant nonlinear effects with fast time response in semiconductors is investigated.
Hybrid Nanostructures: Organic Interconnections and Device Applications
2006 1st International Conference on Nano-Networks and Workshops, 2006
Silicon technology is rapidly progressing toward device sizes in the range of 10 nm. The evolutio... more Silicon technology is rapidly progressing toward device sizes in the range of 10 nm. The evolution rate of silicon technology in next decades will require the use of new materials and processes to develop revolutionary CMOS devices. Organic nanostructures onto semiconductors or metals may provide interesting solutions to address the technological issues of nanoscale devices. In particular, technologies and devices based on organic nanostructures such as carbon nanotubes, semiconductor or metallic nanoparticles, DNA-templated nanowires may supply solutions for on-chip interconnections. The aim of this work is to present recent results on hybrid nanostructures based on gold nanoparticles stabilized by organic coating. Particular emphasis is devoted to the problem of the interconnections at the nanoscale. The resulting hybrid devices are suitable to develop single electron transistors and memories
Uploads
Papers by Ermanno Di Zitti