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The study and modeling of EMC are becoming more critical than ever due to the ubiquitous presence of electronic circuits in all aspects of our lives. Specifically, it is crucial to extend these studies to the new frequencies that, in a few years, will be a reality in modern telecommunications systems, such as 5G and its derived technologies. A specific critical field where the proper EMI shielding has been ensured to avoid EMC problems is the electric autonomous vehicles (EAVs). The huge number of electronics systems in new vehicles will dramatically extend the demands on the EMI shielding solutions used to attenuate the radiated emissions that could affect circuits in the vehicle. Metals or metal alloys are the most common EMI shielding materials since they demonstrate adequate shielding capacity against EMI. However, polymers have become up-and-coming materials for EMI shielding with the characteristics of lightweight, flexibility, cost-effective, easy processing, and resistance to corrosion. Consequently, it is necessary to develop EMI shielding materials based on polymers, plastic materials, and fiber composites that ensure compliance with the different standards that regulate 5G and the proper operation of possible systems susceptible to the intentional and unintended signals generated by this new technology. This contribution focuses on characterizing different composite structures' performance based on fibers combined with conductive materials in terms of shielding effectiveness, covering the 5G sub-6 GHz frequency range.

Typically, low-noise structures tend to have a low number of elements; however, the constant search of better performance and improvement in Low-Noise Amplifiers (LNA) has led to much more intricate designs, and therefore to an increment in the number of components. This work suggests another option: returning to basic and efficient topologies and focus on the optimization methodology to solve the problem and achieve better results. Also, unsophisticated structures mean a higher degree of control over the circuit, and, hence, the reduced number of components enables methods unsuitable for more complex LNAs. An inductorless single-ended gm-enhanced common-gate LNA shows the advantages of this design strategy, obtaining competitive performance. The paper includes the analytical expressions of the topology, and all simulations and statistical analyses use complete technology models provided by manufacter.for accurate results.

This paper aims to assess the economic feasibility for urban microgrids in Australia and Brazil. A real case study from Monash University microgrid is assessed for Melbourne/Australia and a hypothetical similar project is analyzed for Rio de Janeiro/Brazil, considering the economic, technical and regulatory differences between those cities. An economic model was built to assess the economic feasibility of five scenarios that simulate different configurations of the microgrid for each city. Finally, a deep analysis of the results is presented to justify the counter-intuitive conclusion.

The performance of a Near Field Communication (NFC) antenna may be diminished when it is placed close to any conductive surface such as a metallic case or a battery. This degradation is caused due to the stray magnetic field created by the eddy currents induced on the surface, which is opposite to the intended field generated by the NFC antenna. One of the first solutions that come to mind to designers when facing this problem is the use of high permeability magnetic shielding based on sintered ferrite sheets. This is a good approach but something that is not generally taken into account is that these materials introduce an additional inductance to the NFC antenna. If the permeability of the material is too high (respecting the necessary value for solving the problem), this additional inductance results in shifting the resonance frequency to lower values than the desired (13.56 MHz). Thereby this contribution focuses on the analysis of a ferrite-polymer composite magnetic shielding that provides lower relative permeability (µr = 25) at the communication frequency. This approach is more effective against the presence of a metallic element when there is a gap of some millimeters between the conductive surface and the NFC antenna. Therefore, different thicknesses of the same ferrite-polymer material are evaluated and the effect of introducing this kind of shielding between the conductive surface and the NFC antenna is analyzed from the standpoint of the loop antenna equivalent circuit. The results presented are based on the Smith Chart measurement as well as a simulation model that corroborates the results obtained experimentally.

This work proposes a new approach to design a simple and effective LNA reaching very competitive results in 1.2V 65-nm standard CMOS technology. The proposed design uses a transconductance enhancement technique to achieve 2.3 dB of noise figure at the 5 GHz band. The paper exposes the advantages of a reduced number of devices in the circuit and analyses the topology. Simulations with complete technology models and statistical analysis are presented for more precise results.

Sleeve ferrite core is an EMI suppressor widely used to reduce the conductive and radiated electromagnetic noise in cables. The interconnection of different electronic systems through cables is becoming more difficult due to the hard restrictions related to EMC compliance requirements. Thereby, the research of new solutions able to provide a great attenuation ratio in a wide frequency band is a challenge. This contribution focuses on analyzing and comparing the performance of a novel sleeve ferrite solution based on a nanocrystalline (NC) structure with several materials with different compositions. This component is able to provide a high initial permeability value at the same time that maintains it up to some tens of megahertz. In terms of dimensions, NC suppressors can provide the same effectiveness than other materials with more reduced dimensions. The analysis of the impedance dependence of a sleeve ferrite core with its dimensions has been carried out. Five ceramic materials with different initial permeabilities from 380 up to 5000 has been compared with the NC core through representing their impedance traces. The results presented shows that NC provides the higher impedance throughout the frequency range of 1-500 MHz when it is compared with ceramic cores with the same dimensions.

This paper focus on the study of dynamic resistance $(\mathrm{R}_{\mathrm{dyn}})$ over commercial Gallium Nitride High Electromobility Transistors (GaN HEMTs) devices. The first part shows a study of the main mechanism causing $\mathrm{R}_{\mathrm{dyn}}$ , showing that depending on the structure, stress time, voltage applied and switching conditions, the $\mathrm{R}_{\mathrm{dyn}}$ can suffer a relevant increase. Also, it is demonstrated how the use of soft-switching conditions can alleviate trapping effects. Finally, due to the interest over these devices for future space applications, the effects of gamma radiation over the $\mathrm{R}_{\mathrm{dyn}}$ has been studied.

The reduction of embedded portable devices involves a magnetic field interference problem when it integrates Near Field Communication (NFC) due to the presence of conductive surfaces such as ground planes, batteries or metallic enclosures. This contribution is focused on analyzing the ability of an innovative magnetic shielding based on flexible sintered ferrite sheets (FSFS) with the aim of improving the performance of that kind of systems. Thereby, a NFC emitter antenna is characterized when it is close to a conductive surface through an electromagnetic (EM) scanner. The EM scanner composed by a matrix of near field probes that make it possible to determine the effectiveness of the FSFS. The performance analysis is carried out through comparing the power emitted by the antenna with and without placing the FSFS between the antenna and the metallic plane. The results obtained show the ability of this component to shield the communication area from the conductive surface, preserving the original transmitted signal without reducing the communication performance.

Wide bandgap devices such as GaN HEMTs are a promising technology in the field of Power Electronics. Due to the physical properties of the Gallium nitride and the device design, they can outperform their Silicon counterparts for the design of highly efficient power switching converters. However, its design should face certain effects that can diminish its performance. One of such effect is the degradation mechanism known as dynamic onresistance (dynamic RON,), being its mitigation one of the main objectives in the design of the device. In this paper, a circuit is proposed for assessing if this effect is present in GaN transistors in power electronics applications. The circuit allows testing the GaN HEMTs with different stress voltages and times maintaining the desired current level, and allows for repeating the test in successive switching pulses, with adjustable switching frequency and duty cycle, always with the same current, mimicking a real power electronics application, This work was supported in part by the Spanish Government under the Project MINECO-FEDER ESP2015-68117-C2-1-R,in part by the scholarship CEICE-GVA-ACIF-2016-330

Face image analysis continues as an ongoing challenge in biometrics and image processing due to the state variations of facial elements. In this context, the mouth-state plays a fundamental role because its impact on the perception of facial gestures. Current work on mouth-state detection is mainly focused on the creation of classifiers derived from large training datasets. This technique requires extensive training sessions and its results entirely rely on the quality of datasets and learning methods. This paper describes an original approach for detecting mouth-state to support the ICAO standard for face image validation. The proposed approach reduces the error margins by considering face proportions for image segmentation and estimates the magnitude of mouth aperture by conducting an analysis of skin color. Experimentation demonstrates improvements by 21% on the correct detection of mouth-state by slightly affecting the processing time in comparison to the classifiers approach.

Balancing services are used for maintaining the continuous balance between generation and load in the system and keep the frequency stable on its nominal value. The demand for balancing services is increasing with the growing penetration of wind generation into the electricity industry. It is clearly seen that a major challenge of the coming environment for the electricity market is reducing the procurement cost of balancing services. This paper presents a probabilistic spot market model based on integration of day-ahead spot market and the real-time balancing market which aims to trade off preventive actions in the day-ahead spot market with corrective actions in the real-time balancing market. The proposed model is formulated as a bi-level optimization problem. To solve it, the inner optimization problem (reflecting the real-time balancing market) was substituted by its equivalent Karush-Kuhn-Tucker optimality conditions. Conventional spot market model is used as a benchmark in this study. The proposed and conventional spot market designs are applied to modified Nordic 32-bus example system. Comparison of results point out the benefits of the proposed approach over the traditional model.

When a flexible fuzzy rule structure such as those with antecedent in conjunctive normal form is used, the interpretability of the obtained fuzzy model is significantly improved. However, some important problems appear related to the interaction among this set of rules. Indeed, it is relatively easy to get inconsistencies, lack of completeness, redundancies, etc. Mostly these properties are ignored or mildly faced. This paper, however, focuses on the design of a multiobjective genetic algorithm that properly considers all these properties thus ensuring an effective search space exploration and generation of highly legible and accurate fuzzy models.