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The power electronic transformer (PET) or solid-state transformer (SST) is a key technique in the future distribution grid. One of PET's future possible application is the soft normally open points (SNOP) to handle the power and voltage challenge brought by the renewable energy sources. In this paper, a PET-based three-terminal medium-voltage SNOP topology is proposed. The topology consists of three cascade H-bridge (CHB) stages and a multiactive bridge (MAB) stage. The dc voltage control strategy for the proposed PET-SNOP is studied. Two strategies – the CHB+CHB+CHB strategy and CHB+MAB strategies are developed from the existing strategies but they both have some drawbacks. In order to overcome the drawbacks, a novel dc voltage control strategy—CHB×3+MAB strategy is proposed, which combines the advantages and avoids the drawbacks of these two strategies, moreover, it also brings more flexibility and robustness to the dc voltage control. The effectiveness of the proposed PET-SNOP topology as well as the proposed CHB×3+MAB dc voltage control strategy is verified by both simulation and experiment results. [ABSTRACT FROM AUTHOR]

In this paper, we report an integrated soft and transparent visuo-haptic interface, which is compatible with flexible devices and wearable gadgets. The visuo-haptic interface is composed of a touch-sensitive visual display based on polymer waveguides and a dielectric elastomer microactuators (DEMA) array. The touch-sensitive visual display, formed via continuative multistep photolithography, is a multilayered structure with a tactile-sensing layer stacked onto a visual-imaging layer. The dual-functional layer is thin (total thickness: <200 μm) and transparent (transmittance: as high as 90%). The DEMA forming a unit cell of the array is designed as multiple three-dimensional structures with silver nanowires (AgNWs) compliant electrode. When an electric voltage is applied across compliant electrodes formed on the sides, individual microactuators expand directly in an upward direction. Thanks to the vertically deformable design, the DEMA produces programmable large normal forces up to about 30 times of thresholds at a localized area. An output force response of the DEMA is reversible, fast (<1 ms delay), durable (output force degradation: <8% during a million cycles), and large enough to be used in human tactile interfaces. Due to the synergetic benefits from the functional layers, the visuo-haptic interface allows demonstration of programmable tactile response with visual information while being intimately attached on human skin. [ABSTRACT FROM AUTHOR]

PM2.5 is an important global air pollution issue. PM2.5 causes various problems on the environment and human health. Even though PM2.5 of the outdoor air is eliminated by particulate air filters, the chemicals adsorbed on the filtered PM2.5 can be outgassed and introduced into the semiconductor manufacturing facilities and processes, thus causing defects on the semiconductor chips by producing particles and haze as airborne molecular contamination. Therefore, estimating the amount of the outgassing from PM2.5 is a very important factor to control gaseous contaminants in the semiconductor industry. In this paper, the PM2.5 samples at different PM2.5 mass loadings were collected in Xi’an, China and evaluated using the soft X-ray radiolysis method for determining the relation between the outgassing and the PM2.5 mass loading. The PM2.5 samples were also analyzed by several methods for quantifying organic and elemental carbons, water soluble ions, and organic compounds in the PM2.5 samples. The outgassing measured by the soft X-ray method increased linearly with the PM2.5 mass loading, and the chemical analyses explained that the organic carbon (OC) was dominantly detected by the soft X-ray method in the current study. Moreover, the sampling location of the PM2.5 affected on the organic compounds of the PM2.5. [ABSTRACT FROM AUTHOR]

Numerical experiments are carried out on a low-energy (2.2 kJ) Mather-type Egyptian Atomic Energy Authority-Plasma Focus (EAEA-PF1) to investigate the optimum combination of all electrode system dimensions and gas pressure for maximum argon soft X-ray (SXR) yield, $Y_{\mathrm {SXR}}$ , using Lee Model RADPF5.15. This paper aims to finalize the first step prior to building an automated method of optimization that could be applied when a low-energy dense plasma focus is designed or need to be reconfigured, for this purpose, and to assist further research efforts in this field. The second part of the study deals with the investigation of the role of changing outer electrode radius “b” and the outer to inner radii ratio “c” on plasma focus (PF) parameters such as ion density, pinch duration, and column length and how are these, consequently, related to the maximum SXR yield. It is shown that lower radius ratio values (typically less than 2) are favored over higher ones, for argon SXR yield, and unlike most of the low-energy PF devices that are designed for this purpose. It is also shown that inductance and pinch current are only affected by the dimension of inner electrode radius, while the ion density, pinch duration, and focus volume are also affected by the change of outer electrode radius. [ABSTRACT FROM AUTHOR]

Cross-layer reliability is becoming the preferred solution when reliability is a concern in the design of a microprocessor-based system. Nevertheless, deciding how to distribute the error management across the different layers of the system is a very complex task that requires the support of dedicated frameworks for cross-layer reliability analysis. This paper proposes SyRA, a system-level cross-layer early reliability analysis framework for radiation induced soft errors in memory arrays of microprocessor-based systems. The framework exploits a multi-level hybrid Bayesian model to describe the target system and takes advantage of Bayesian inference to estimate different reliability metrics. SyRA implements several mechanisms and features to deal with the complexity of realistic models and implements a complete tool-chain that scales efficiently with the complexity of the system. The simulation time is significantly lower than micro-architecture level or RTL fault-injection experiments with an accuracy high enough to take effective design decisions. To demonstrate the capability of SyRA, we analyzed the reliability of a set of microprocessor-based systems characterized by different microprocessor architectures (i.e., Intel x86, ARM Cortex-A15, ARM Cortex-A9) running both the Linux operating system or bare metal in the presence of single bit upsets caused by radiation induced soft errors. Each system under analysis executes different software workloads both from benchmark suites and from real applications. [ABSTRACT FROM AUTHOR]

This paper shows the correlation of the characteristic Ne soft X-ray (SXR) signal pulse with computed dynamics of the plasma focus using doped neon in Ne (97.5%)/Kr (2.5%) admixtures. The Lee model code is coupled with a specifically designed correlation excel template. The results show that typically, the characteristic Ne SXR pulse signal starts after the start of the reflected shock (RS) and before the beginning of the pinch. Specifically, in the illustrated shot, the RS phase starts at $3.375~\mu \text{s}$ while the pinch phase starts at $3.384~\mu \text{s}$. The characteristic Ne SXR signal pulse starts at $3.377~\mu \text{s}$ , which is 2 ns after the start of the RS and 7 ns before the pinch starts. There is a consistent trend of Ne SXR correlation with the computed dynamics in the Ne doped with Kr admixtures up to a doping level of 2.5%. [ABSTRACT FROM AUTHOR]

This paper presents a new topology for a fully bidirectional soft-switching solid-state transformer (S4T). The minimal topology, featuring 12 main devices and a high-frequency transformer, does not use an intermediate dc voltage link, and provides sinusoidal input and output voltages. The S4T can be configured to interface with two- or multiterminal dc, single- or multiphase ac systems. An auxiliary resonant circuit creates zero-voltage-switching conditions for main devices from no-load to full-load, and helps manage interactions with circuit parasitic elements. The modularized structure allows series and/or parallel stacking of converter cells for high-voltage and high-power applications. [ABSTRACT FROM PUBLISHER]