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This paper describes IMPREAL 2.0, a system developed in LabVIEW that automates the acquisition of voltage impulse waveforms from digital oscilloscopes and implements the mathematical procedures described in the new standards from the International Electrotechnical Commission IEC 60060:2010. The system controls commercial digital oscilloscopes and is able to automatically calculate the time and amplitude parameters of lightning impulses (LI), switching impulses, chopped LI, and oscillating impulses (lightning and switching) waveforms, generating test reports tailored for the needs of the calibration and tests labs. The estimated uncertainty due to the software processing is also presented here, following the guidelines defined by standard IEC 61083-2:2013.

This paper proposes a new technique based on the employment of genetic algorithms to solve the inverse biomagnetic problem. The biomagnetic measurements analyzed in this paper were performed on isolated rabbit hearts and acquired by a 16-Channel SQUID system. The developed method focused on defining the single equivalent current dipole that best fits the experimental data. The genetic algorithm is used to determine the position, angle and magnitude of the current dipole, attempting to minimize the error between the experimental magnetic field map and the one obtained by using the estimated current dipole.

CMOS technology miniaturization limits have promoted research on new alternatives which can keep the technologically advanced level of the last decades. Quantum-dot cellular automata (QCA) is a new technology in the nanometer scale that has been considered as one of these alternatives. QCA have a large potential in the development of circuits with high space density and low heat dissipation and allow the development of faster computers with lower power consumption. Differently from conventional technologies, QCA do not codify information by means of electric current flow, but rather by the configuration of electrical charges in the interior of the cells. The Coulomb interaction between cells is responsible for the flow of information. This paper proposes the use of computational intelligence techniques in the simulation and in the automatic synthesis of QCA circuits. The first results show that these techniques may play an important role in this research area since they are capable of simulating efficiently and fast, synthesizing optimized circuits with a reduced number of cells. Such optimization reduces the possibility of failures and guarantees higher speed

The International Electrotechnical Commission (IEC) issued in 2010 a revision of the family of standards IEC 60060, describing, among other requirements, how to calculate the various amplitude and time parameters used to evaluate high voltage impulse waveforms. However, the standards are not clear in some aspects, especially when describing tail chopped lightning impulses. This paper aims at describe in detail how to properly estimate the time parameters of such impulses.

It is often challenging to supply high alternating currents at high frequency to inductive loads, because it demands very high voltages at the load terminals. Usually, in such a scenario, the use of large, heavy and expensive high-voltage/power active devices is mandatory. However, the set of requirements of an ongoing project, demanding portability, low cost and electrical efficiency, led to the necessity of working on that issue. An original method that enables the use of low-voltage active devices and a low-voltage source to supply high currents to inductive loads is described. The basic principle used was the reduction of the equivalent impedance seen by the active devices at the desired frequency, leading to lower terminal voltages. Further adaptations were made, including measures to improve power dissipation and protection from transients. The respective developed electronic circuit is shown and experimentally analysed.

The construction of new Ultra High Voltage laboratories requires more studies about standards for equipment as well as for testing and measurement techniques. Currently, the analysis of tail chopped lightning impulse waveforms is possible only by prior application of a full reference lightning impulse, creating difficulties for testing and processing of waveforms. A new method for evaluating the relevant parameters of tail chopped waveforms has been previously developed and this paper studies the effect of the overshoot in this alternative method.

With a more realistic vision of a possible limit for miniaturization of components with conventional CMOS technology, a new technology has surfaced -molecular electronics which, from the bottom-up approach, aims at the construction of electrical devices to implement computation using individual or small collections of molecules, offering an alternative way to build nanoscale circuits. These circuits have the potential to reduce device size and fabrication costs by several orders of magnitude relative to conventional CMOS. Recently, some mechanisms have been considered as a basis to molecular electronic systems design. Two terminal molecular devices that work as diodes have been synthesized, with similar behavior to rectifying and tunnel diodes. In this article, a study on the synthesis of molecular circuits is presented, integrating simulated molecular devices as the molecular Tour-Reed diode based on the evolvable hardware (EHW) paradigm.

Over the last decade, giant magnetoimpedance (GMI) sensors have been intensively studied as a new possibility for measuring ultra-weak magnetic fields. Presented is a newly developed method that allows the enhancement of the impedance phase sensitivity of GMI sensors and, consequently, increases the sensitivity of phase-based GMI magnetometers. The electronic circuit that implements the proposed method is presented and discussed, and the obtained experimental results indicating its effectiveness are shown.

This manuscript presents and describes an automated system for the evaluation of the dynamic performance of high-voltage measurement systems, according to the requirements of the standard IEC 60060-2/2010. The system was developed in LabVIEW and controls the acquisition, measurement and analysis of step response tests of measurement systems, automatically calculating the relevant amplitude and time parameters.

Giant Magnetoimpedance (GMI) magnetometers are one of the most recent families of magnetic transducers, being characterized by their potential to achieve high sensitivities. The sensitivity of magnetic transducers is directly related to the sensitivity of its sensor elements. Thus, optimizing the sensitivity of these sensor elements is a critical part of the magnetometers development chain. This paper describes an automatic characterization system designed for the measurement of the electrical impedance of Giant Magneto- Impedance samples. The measurement uncertainties of the system were verified and discussed. The high speed of measurement attained with the use of this system, implemented in LabVIEW, allows for the rapid determination of the optimal operational point of GMI magnetometers.