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In this paper, we report the characterization and modeling of multi-finger gate all around (GAA) nanowire (NW) FETs (NWFETs) from dc to 14 GHz. The self-heating effect (SHE) in NWFETs is investigated experimentally using the small-signal output conductance (${g}_{{\text {ds}}}$) technique. The frequency-dependent complex thermal impedance, ${Z}_{{\text {th}}}({f})$ , is extracted by fitting an ${n}$ th-order thermal network with the experimental data. We show that the temperature rise $\Delta {T}$ (=85 °C) due to SHE is significant in short-channel silicon on insulator (SOI) NWFETs. Finally, we have evaluated the RF figure of merit (FOM) for these NWFETs as ${f}_{T}$ (=70 GHz) and ${f}_{\text {max}}$ (=80 GHz). We also report the RF performance metric sensitivity on temperature, $\partial {f}_{\text {max}}/\partial {T}_{{\text {amb}}}$ ($\approx -0.104$ GHz/K). The reported BSIM-CMG compact model shows a good correlation with the measurement data. [ABSTRACT FROM AUTHOR]

In this paper, an array wire-to-wire surface dielectric barrier discharge (DBD) structure is used to generate large-scale plasma by bipolar nanosecond pulse power in atmospheric air. The quantity of electrodes can be adjusted from 1 to 10 for varying discharge area. The applied voltage and discharge current are measured, the discharge images are captured, and optical emission spectra (OES) are collected. The discharge power, discharge area, and OES intensity for a single group of/and whole structure are calculated. The vibrational and rotational temperatures are simulated by the OES of N2 (C-B, $\Delta \nu =-2$), and the effects of the quantity of electrodes on discharge current, discharge power, discharge area, OES intensity, and vibrational and rotational temperatures are investigated. The results show that the discharge current has two main peaks during single applied pulse voltage, and decays in a fluctuant type. As the quantity of electrodes increases, the peak value of discharge current increases and the decaying time from peak value to zero around becomes longer. The discharge power, discharge area, and OES intensity have increasing tendencies, and those of the single group of wires decrease. In addition, when the quantity of electrodes increases, the vibrational temperature increases first and then decreases, and the rotational temperature varies in a fluctuant type. [ABSTRACT FROM AUTHOR]

In previous work, the performance of a compact and cost-effective point-of-care (PoC) device based on the increase relative optical power (IROP) methodology is reported and it is determined the enhancement in comparison with standard high-resolution spectrometry in terms of limit of detection. This paper describes a new label-free IROP-based biomedical device capable of working with low concentration of reagents and low sample volume per measurement in order to be used for screening different steps necessary in immunoassay optimization. This new approach significantly improves the sensing performance in terms of read-out signal ($\Delta $ IROP) per nanometer of biofilm in comparison with our previous work. This improvement is achieved due to the implementation of a laser as light source of the optical read-out system and the redesign of Fabry–Perot transducers by optimizing their reflectivity response and reducing their sensing area. For demonstrating the screening capability of this new PoC device in several immunoassays steps and methodologies, a C-reactive protein detection assay was carried out as a potential application and assay model. It is remarkable that only $10~\mu \text{L}$ of sample was used per measurement. This label-free IROP-based device complies an easy-to-use and cost-effective tool for immunoassays optimization in terms of performance, reagents cost, and measuring time. [ABSTRACT FROM AUTHOR]

For decades, power system stabilizers paired with high initial response automatic voltage regulators have served as an effective means of meeting sometimes conflicting system stability requirements. Driven primarily by increases in power electronically-coupled generation and load, the dynamics of large-scale power systems are rapidly changing. Electric grids are losing inertia and traditional sources of voltage support and oscillation damping. The system load is becoming stiffer with respect to changes in voltage. In parallel, advancements in wide-area measurement technology have made it possible to implement control strategies that act on information transmitted over long distances in nearly real time. In this paper, we present a power system stabilizer architecture that can be viewed as a generalization of the standard $\Delta \omega$ -type stabilizer. The control strategy utilizes a real-time estimate of the center-of-inertia speed derived from wide-area measurements. This approach creates a flexible set of trade-offs between transient and small-signal response, making synchronous generators better able to adapt to changes in system dynamics. The phenomena of interest are examined using a two-area test case and a reduced-order model of the North American Western Interconnection. To validate the key findings under realistic conditions, we employ a state-of-the-art co-simulation platform to combine high-fidelity power system and communication network models. The benefits of the proposed control strategy are retained even under pessimistic assumptions of communication network performance. [ABSTRACT FROM AUTHOR]

Self-heating in fully depleted silicon-on-insulator (FDSOI) metal–oxide–semiconductor field-effect transistors (MOSFETs) is experimentally studied using the gate resistance thermometry technique, in a wide temperature range from 300 down to 4.2 K. We demonstrate that below 160 K, the channel temperature increase ($\Delta {T}$) due to self-heating starts to deviate significantly from the linear variation with the dissipated power, leading to an apparent power dependent thermal resistance. This power dependence is interpreted in terms of temperature dependent thermal conductivity. The thermal resistance dependence on the active device temperature (${T}_{\text {Device}}$) indicates that the former one is mainly driven by the thermal conductivity of the oxide layer. Moreover, based on this dependence we reconstructed the channel temperature increase for each dissipated power and ambient temperature, and we found that the calculated values were in a good agreement with the experimental ones. Results indicate that even at low temperatures, thermal resistance does not depend significantly on the silicon channel thickness (ranging from 7 up to 24 nm), whereas the buried-oxide thinning (145 and 25 nm) strongly reduces the magnitude of the thermal resistance. Finally, this paper intends to fill the gap of experimental data concerning self-heating in advanced FDSOI transistors at low temperatures, revealing limitations and perspectives that should be taken into account for future work. [ABSTRACT FROM AUTHOR]

In this paper, we report measurements in Colorado and Utah of the disturbed very-low-frequency (VLF) signals from the NML Navy transmitter in North Dakota during the 2017 solar eclipse. Using an occultation mask of solar fluxes together with detailed chemistry and VLF propagation simulations, we quantify the D-region response to the eclipse, in terms of electron density variation, as well as the expected signatures of VLF transmitter signals. The VLF measurements, including an anomalous amplitude enhancement recorded in UT, can be quantitatively explained using the Wait and Spies ionospheric profile with a sharpness parameter of $\beta = 0.3$ km−1 above ~55 km and an increase in the D-region ionosphere height of $\Delta h' \simeq 8$ km. This sharpness parameter is consistent with previously reported rocket measurements and first-principles calculations. The best-fit results suggest a reduction of D-region electron density by ~90% during the eclipse in the D-region, implying an occultation of Lyman- $\alpha $ by nearly 99%. This finding agrees with detailed calculations of time-dependent obscuration factors utilizing the He 30.4-nm images from Solar Dynamics Observatory as a proxy for the distribution of Lyman- $\alpha $ across the solar disk and limb. Moreover, the present results show that subionospheric VLF propagation is sensitive to the sharpness parameter of the electron density profile in the D-region. Previously reported first-principles simulations have shown that the sharpness parameter is mostly controlled by the background concentration of minor neutral species. Thus, the VLF technique can be likely used to remotely sense these neutral species at and below the effective reflection altitudes of VLF waves. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) is an enabling technology for electric vehicles (EV), as it eliminates driver intervention during charging. Major challenges to the adoption of WPT systems include coil misalignment and large air-gap WPT, both of which degrade the transfer efficiency. To address these issues, this article presents a compact WPT charger for the rear of an EV, capable of correcting lateral misalignment $\Delta$ x using two integrated electromagnetic coils. The air-gap $\Delta$ y is reduced due to the rear placement of the charging pads. The variation in $\Delta$ y, however, increases due to vehicle parking accuracy, which impacts the operation of the electromagnetic coils. This article proposes a closed-loop three-stage position-correcting control algorithm capable of detecting the impedance and resonant frequency of the system, which, in conjunction with the electromagnetic coils, results in improved vehicle alignment. The experimental prototype achieves a peak dc–dc efficiency of 90.1% at 5 kW WPT. With $\Delta$ y = 50 mm, the electromagnetic coils laterally align the pads within 1.75 s and correct $\Delta$ x as large as 240 mm. The position-correcting control was successfully demonstrated in four parking scenarios with the charging pads being corrected to within a 10-mm radius of perfect alignment. [ABSTRACT FROM AUTHOR]

The additional microwave radiation from underground rock mass (lithosphere) that is caused by tectonic activity and alternating crustal stress has been shown to be a detectable electromagnetic signal via satellite remote sensing. However, the emission of microwave radiation produced inside the lithosphere will be affected by its overburden matter, such as sand, soil, water, and vegetation, and this effect is unknown. In this article, we use a C-band microwave radiometer to detect the variations in the microwave brightness temperature ($T_{B}$) of rock samples in the process of axial loading. For the rock samples, the surface was bare and covered with dry sand or humid sand. The experimental detection illustrates that the dry sand unexpectedly allows more stress-associated additional radiation ($\Delta T_{B}$) to be received by the radiometer, while humid sand shows significant extinction of $\Delta T_{B}$. Both the radiative transfer theory and the stress-activated positive hole hypothesis are applied to interpret the mechanisms of the effect of dry and humid sand layers on $\Delta T_{B}$. The outflow of stress-activated positive holes is from inside the loaded rock, and hence their accumulation beneath the surface of the sand layer is expected to reduce the local dielectric permittivity of sand, thereby making the detected $\Delta T_{B}$ by the microwave radiometer to be larger than that extrapolated theoretically in accordance with radiative transfer theory. This article is valuable for understanding the diverse $T_{B}$ anomalies that have been observed prior to tectonic earthquakes, and it facilitates the evaluation of the potential application of $\Delta T_{B}$ to seismic monitoring and earthquake prediction. [ABSTRACT FROM AUTHOR]

The proposed fully integrated digital-intensive system on chip (SoC) allows dual-mode protocols of Bluetooth low energy (BLE) 5.0 and IEEE802.15.4 with extended-range wireless connectivity and ad hoc mesh networks for Internet-of-Things (IoT) systems in wireless sensor networks. The SoC fully integrates a dc–dc converter, LDOs, a digitally controlled crystal oscillator (DCXO), a PHY, a microcontroller (MCU), a security engine, an SRAM, and an eFlash memory. A triple-supply configuration and low-voltage circuit design enable the SoC to be applied for a wide range of battery-powered systems energy-efficiently and to extend battery lifetime. The TRX employs a low insertion-loss on-die TRX switch with impedance matching circuits, a pseudodifferential current-mode class-D PA with HD2 calibration, a low-IF RX architecture with fast AGC algorithm and complex CT- $\Delta \Sigma $ ADCs, and a low-power all-digital phase-locked loop (ADPLL) with fast settling injection LDOs and an LMS-based two-point direct frequency modulation structure. The TRX implemented in a 28-nm CMOS process achieves an output power of +10 dBm with a calibrated HD2 of −63 dBc while consuming 45 mW and sensitivities of −98 dBm in 2-Mb/s BLE and −102 dBm in 256-kb/s IEEE802.15.4 at ${10}^{-3}$ BER while consuming 6 mW. [ABSTRACT FROM AUTHOR]

Compact polarimetry is a dual-polarization hybrid imaging mode and provides partially backscatter characteristics of scatterers. The compact polarimetric (CP) synthetic aperture radar (SAR) measures the combinations of fully polarimetric (FP) scattering coefficients, which is dependent on the transmit-wave polarization state. The backscattered wave is fully described by a 2-D complex scattering vector, in which the dual-channel polarization ratio represents the vector nature for describing target polarimetric properties. However, due to the dependence of CP measurements on the transmit wave, the complex channel ratio is explained differently for the same scatterers under different observation modes, e.g., the channel ratio ρ = ± j under the left circular mode and ρ = ±1 under the linear π/4 mode for the canonical trihedral and dihedral scatterers. The explanation diversity is inconvenient for the use of CP data, resulting in nonunified target decomposition algorithms. In this study, first, we propose a new formalism method for the general CP SAR mode, such that all CP mode observables are described based on the same standard for target scattering characterization. This provides potential for developing unified CP decomposition algorithms. Then, based on this formalism, a polarization ratio-based scattering characterization method is proposed, which is mathematically equal to the FP ΔαB/αB method but without any scattering assumption. Theoretical analyses and discussions are provided. Experiments show that the proposed method is efficient for compact polarimetric scattering interpretation. [ABSTRACT FROM AUTHOR]