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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]

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]

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]

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]

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]

Ar divergent gas-puff ${Z}$ -pinch discharge with reversed polarity was performed. Spectroscopic and spatial properties of K-shell and L-shell radiations emitted from highly ionized Ar ions were investigated. It was confirmed that L-shell radiation was spreading in the axial direction, whereas K-shell radiation was emitted from a small spot. The spot size of K-shell radiation was measured, and the diameter of the spot was $34 \pm 9~\mu \text{m}$. Small creatures were observed using the K-shell radiation emitted from the spot. Repetitive and intense point radiation source with limited spectrum was realized by the divergent gas-puff ${Z}$ -pinch. [ABSTRACT FROM AUTHOR]

A compact pulse power system has been developed and successfully tested for soft X-ray lasing at 46.9 nm in argon plasma generated by fast capillary discharge scheme. The system has been designed with the aim to generate high current with a high rate of rise in the gas-filled ceramic (Al2O3) capillary (radius 1.4 mm and length 150 mm). The electrical parameters for the compact system were fixed using circuit simulation and the setup design was optimized using electrostatic field simulation software. A 10-stage 100–400 kV, 6-nF Marx generator is used to pulse charge the 3.2 nF, 35-nH water filled coaxial capacitor. The improvement in the output laser energy has been observed due to faster rise time of discharge current. The highest current observed was 70 kA, achieving a rate of rise of current $\sim 2\times 10^{12}$ A/s in 97 mm long, 2.8 mm inner diameter capillary. We strongly believe that the performance of the system is suitable for study of discharge plasmas from gasses other than the argon for exploring recombination-based X-ray lasing at wavelengths shorter than 46.9 nm. [ABSTRACT FROM AUTHOR]

Measured current waveforms at different neon pressures from two different plasma focus (PF) devices, namely, NX2 and NX1 are used for analysis using the Lee code. The model parameters of mass ( fm and $f_{{\text {mr}}} ) and current ( f\text {c} and f\mathrm {cr} ) in axial and radial phase, respectively, are obtained by fitting the computed current waveform to the measured current waveform for each pressure over a range of pressures in neon. The results show that the value of fm and f\mathrm {mr} ranges from 0.07 to 0.12 and 0.09 to 0.20, respectively, over the pressure range 1.0–5.0 Torr for NX2, whereas for NX1 it ranges from 0.020 to 0.024 and 0.048 to 0.08, respectively, over the pressure range 7.5–12 Torr. In all cases, the values of fc and f\mathrm {cr} are fixed at 0.7. Comparison of computed and measured soft X-ray (SXR) yield using fit model parameters for both devices shows good agreement. An important finding is that despite the noticeable variation of mass factors over the whole pressure range, a representative set of model parameters is found for each machine which may be taken as fixed over the range of pressures producing a good yield. In particular, for a high-performance PF using conventional electrode structure the representative set is: fm = 0.075 , fc \,\, = \,\, 0.7 , f\mathrm {mr} =0.1 , and f\mathrm {cr}= \,\, 0.7 . This is valuable information for neon SXR design purposes. [ABSTRACT FROM PUBLISHER]

Large format arrays of transition edge sensor (TES) are crucial for the next generation of X-ray space observatories. Such arrays are required to achieve an energy resolution of ΔE< 3 eV full-width-half-maximum (FWHM) in the soft X-ray energy range. We are currently developing X-ray microcalorimeter arrays as a backup option for the X-IFU instrument on board of ATHENA space telescope, led by ESA and foreseen to be launched in 2031. In this contribution, we report on the development and the characterization of a uniform 32 × 32 pixel array with (length × width) 140 × 30 μm2 TiAu TESs, which have a 2.3 μm thick Au absorber for X-ray photons. The pixels have a typical normal resistance Rn = 121 m Ω and a critical temperature Tc ~ 90 mK. We performed extensive measurements on 60 pixels out of the array in order to show the uniformity of the array. We obtained an energy resolutions between 2.4 and 2.6 eV (FWHM) at 5.9 keV, measured in a single-pixel mode at AC bias frequencies ranging from 1 to 5 MHz, with a frequency domain multiplexing (FDM) readout system, which is developed at SRON/VTT. We also present the detector energy resolution at X-ray with different photon energies generated by a modulated external X-ray source from 1.45 keV up to 8.9 keV. Multiplexing readout across several pixels has also been performed to evaluate the impact of the thermal crosstalk to the instrument's energy resolution budget requirement. This value results in a derived requirement, for the first neighbour, that is less than 1 × 10−3 when considering the ratio between the amplitude of the crosstalk signal to an X-ray pulse (for example at 5.9 keV). [ABSTRACT FROM AUTHOR]

This article presents a prototype 22.4 μm pixel pitch global shutter (GS) wide dynamic range (WDR) soft X-ray CMOS image sensor (sxCMOS). Backside-illuminated (BSI) pinned photodiodes with a 45-μm thick Si substrate were introduced for low noise and high radiation hardness to high energy photons. Two-stage lateral overflow integration capacitor (LOFIC) and voltage domain memory bank with high-density Si trench capacitors were introduced for WDR and for GS. The developed sxCMOS achieved maximum 21.9 Me− full well capacity with a single exposure 129 dB dynamic range by GS operation. Over 70% quantum efficiency (QE) toward soft X-ray was successfully achieved. The developed prototype sxCMOS is a step forward toward a 4 M pixel detector system to be utilized in next-generation synchrotron radiation facilities and X-ray free-electron lasers. [ABSTRACT FROM AUTHOR]

Back-thinned silicon detectors offer a high response over a very broad spectrum for direct detection by providing an efficient optical path into the sensing silicon avoiding front face structures manufactured from metal, polysilicon, nitrides, and oxides that may absorb the incident light before reaching the sensing silicon. We have tested two CCDs with different back-surface shallow p+ implant thicknesses (basic and enhanced) at the M4 line (wavelength between 40 and 400 nm) at Physikalisch-Technische Bundesanstalt (PTB)’s Metrology Light Source in Berlin. This characterization in the ultraviolet spectral range extends the soft X-ray quantum efficiency (QE) data set previously acquired with the exact same devices. Due to the short absorption depth and the scope for many types of interactions of the device materials with ultraviolet photons, QE measurement and stability of the device against extended exposure in the UV are of ongoing interest. Therefore, QE measurements have been carried out before and after exposures to quantify any change in behavior. To allow characterization of the passivation processes only, the devices have no antireflection coating. The measured QE of the standard back-thinned CCD is below 10% between 70 and 370 nm. An average additional 5% efficiency is achieved in the enhanced device within the same range. At the limits of the measured spectrum, toward soft X-rays or toward the visible range, the QE increases and the difference between the standard and the enhanced process is reduced as the photon absorption length increases beyond the immediate back-surface. The measured QE after long high-flux exposures at 200 nm shows remarkable improvement. [ABSTRACT FROM AUTHOR]

The measured current waveforms of PF1000 plasma focus operating in neon are first fitted to the computed currents using the Lee model for the pressures of 0.5 and 0.8 torr. The fitting fixes the model parameters. The code is then run to study and to optimize the soft X-ray yield from (~352 kJ) PF1000 device. The maximum characteristic soft X-ray (H-like and He-like lines) yield of 4.2 kJ is found to occur at the pressure of 0.85 torr, with the pinch duration of 207 ns and with an all-line yield of 4.8 kJ. Maximum compression (corresponding to smallest pinch radius) of 0.585 cm with the duration of 224 ns is obtained at 1 torr with the greatest all-line yield of 7.1 kJ but a lower characteristic soft X-ray yield of 3.2 kJ. Detailed computation results indicate that the maximum compression (minimum pinch radius) at 1 torr is attributed to two mechanisms: thermodynamics specific heat ratio effects and radiative losses. [ABSTRACT FROM PUBLISHER]

Magnitnoe Obzhatie (MAGO)/magnetized target fusion (MTF) thermonuclear experiments executed with a goal of producing the target plasma heated up to temperatures of hundreds of electronvolts, intended for subsequent compression by an imploding liner accelerated by explosion products, are reviewed. In MAGO/MTF experiments, plasma chambers were used consisting of two or three compartments connected by narrow nozzles: acceleration cylinder compartment and deceleration/fusion compartments (cylindrical or hemispherical). A technology of plasma chamber laboratory conditioning is described. Neutron and soft X-ray pulses are presented and obtained in experiments with chambers powered by an explosive magnetic generator. Irrespective of the chamber geometry and number of compartments, the X-ray pulse consists of a highly intensive peak with a duration of 1~\mu \texts and more than a 10- \mu \texts -long low-intensity tail. The neutron pulse is time coincident with the X-ray peak. Yields up to 10^13 neutrons were detected in experiments with two-compartment chambers. Three-compartment chambers with an intermediate compartment are believed to be more promising for the compression. The results are described of the latter MAGO-IX experiment, the only successful experiment with the three-compartment chamber, in which the yield of 2\times 10^12 neutrons was detected in the third compartment and the yield in the middle compartment was many times lower. [ABSTRACT FROM AUTHOR]

The six-phase Lee model code was developed to compute the anomalous resistance phase (RAN) following the pinch phase in a plasma focus (PF) discharge. One important method to check such modeling is to look at the soft X-ray (SXR) emission time profile and to correlate this to the PF dynamics. A two-channel filtered SXR spectrometer coupled with an Excel-based analytical template was recently developed to speed up the correlation process. Using this system, we have determined that the neon PF typically operates in a normal (N) mode in which it emits characteristic He-like H-like neon line SXR (in a photon energy window of 900–1550 eV) reproducibly and efficiently. The characteristic neon line SXR pulse straddles the pinch duration starting strongly 10 ns before the start of the pinch, then diminishes through the 10-ns pinch and tails off into the subsequent RAN1 phase. We present the correlated time profiles of shots operating in the efficient N mode as well as, for comparison, poor shots, which are distinctly different in SXR time profiles. The profiles indicate the difference in dynamics of normal and poor shots. Statistics are presented as well as comparison of the yields from the numerical experiments and measurements. In the series that were studied the proportion of N-mode operation ranges from 70% in one series to 80% in another series over pressure range 1–4 torr. At 2 torr, it was found that 90% recorded the normal N profile. The results reinforce the view that while the Lee Model code incorporates the correct physics in its sequence of phases, refinement is needed to extend the radiative phase to the period before the pinch. [ABSTRACT FROM PUBLISHER]

Schottky barrier diode (SBD) radiation detectors have been fabricated on n-type 4H-SiC epitaxial layers and evaluated for low energy x- and \gamma-rays detection. The detectors were found to be highly sensitive to soft x-rays in the 50 eV to few keV range and showed 2.1 % energy resolution for 59.6 keV gamma rays. The response to soft x-rays for these detectors was significantly higher than that of commercial off-the-shelf (COTS) SiC UV photodiodes. The devices have been characterized by current-voltage (I–V) measurements in the 94–700 K range, thermally stimulated current (TSC) spectroscopy, x-ray diffraction (XRD) rocking curve measurements, and defect delineating chemical etching. I-V characteristics of the detectors at 500 K showed low leakage current (<2 nA at 200 V) revealing a possibility of high temperature operation. The XRD rocking curve measurements revealed high quality of the epitaxial layer exhibiting a full width at half maximum (FWHM) of the rocking curve \sim3.6 arc sec. TSC studies in a wide range of temperature (94–550 K) revealed presence of relatively shallow levels (\sim0.25 eV) in the epi bulk with a density \sim 7\times 10^13 cm^-3 related to Al and B impurities and deeper levels located near the metal-semiconductor interface. [ABSTRACT FROM PUBLISHER]