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In this article, the observer-based $\mathcal {L}_{2}-\mathcal {L}_{\infty }/ \mathcal {H}_{\infty }$ mixed control issue for uncertain nonlinear plants in the presence of measurement outliers is investigated under interval type-2 (IT2) Takagi–Sugeno (T–S) fuzzy approach. Through using lower and upper membership functions, the uncertainties that exist in nonlinear systems can be captured efficaciously. For the sake of reducing the effect of abrupt abnormal signals that disturb the measurements utilized for the purpose of state estimation, a novel fuzzy observer is designed via utilizing the adaptive saturation of output errors. After that, sufficient conditions are derived to ensure the exponential stability with a mixed $\mathcal {L}_{2}- \mathcal {L}_{\infty }/\mathcal {H}_{\infty }$ performance level of considered systems on the basis of Lyapunov stability theory. Finally, the usefulness of the new designed control approach is confirmed through two demonstrative simulation examples.

A model for the peak frequency in the imaginary part of ${Y}_{{22}}$ (Im( ${Y}_{{22}}{))}$ based on the bias for gallium nitride (GaN) high electron mobility transistors (HEMTs) is investigated while considering both self-heating (SH) and Poole–Frenkel (PF) (electric field) effects. The peak frequency of Im( ${Y}_{{22}}{)}$ corresponds to the emission time constant of the trap in the GaN layer. In this study, ${Y}_{{22}}$ for GaN HEMTs were measured for low frequencies at which the traps respond by significantly changing not only drain voltage ( ${V}_{\text {DS}}{)}$ but also gate voltage ( ${V}_{\text {GS}}{)}$ . Because the vector network analyzer used ac with an extremely small power of −20 dBm as a signal for sensing the trap, the trap properties can be measured at a fixed dc bias. In this model, the SH effect is introduced to replace the ambient temperature in the conventional Arrhenius equation by simulating the lattice temperature. The PF effect introduces the apparent activation energy, based on the simulated electric field at the channel under the gate field edge of the drain side. The electric field is related to the voltage between the gate and drain. This model is consistent with the experimental data for a wide range of transistor biases, i.e., from the ${V}_{\text {GS}}$ near the pinch-off voltage to the ON-state condition, and the ${V}_{\text {DS}}$ in the saturation region at ambient temperatures between 23 °C and 160 °C. Furthermore, using this model, we confirmed that the PF effect dominates at a low ${V}_{\text {GS}}$ of −2 V near the pinch-off.

An effective overmoded circuit is proposed to support efficient interaction with two beams for the development of high power extended interaction oscillators (EIOs) toward sub-terahertz (THz) and higher frequency. The circuit design focuses on the effect of the frequency-determining parameter on mode characteristics of the $\mathrm{TM}_{{1} {n}}$ sequence. Frequency equivalence between $\mathrm{TM}_{{1} {n}}$ modes with different ${n}$ supports the mode selection for two-beam interaction. Accordingly, the TM13 mode is selected to duplicate the dispersion relation around the axial mode of $2\pi $ and ohmic loss of conventional TM11 mode used in conventional single-beam circuits. On this basis, the overmoded circuit is formed with two beams based on the TM13 mode. In order to verify its effectiveness, a 0.22-THz EIO is designed with the overmoded circuit and, most importantly, the effect of the uniformity of two beams on the EIO performance is simulated. When the current of one beam is assumed to be constant and that of another beam is increased, the power is increased linearly and then tends to be saturation. This shows good capability of the EIO in interacting with nonuniform two beams, which is critical for its stable operation. Simulation results have shown the achievement of the average power of 0.22-THz wave over 1.26 kW with double beams at 23 kV and each current of 0.2 A.

Conventionally, silver (Ag) electrodes for organic thin-film transistors (OTFTs) are prepared by evaporated method at high temperature. In this work, we report a new methodology to fabricate the Ag source/drain electrodes of flexible OTFTs arrays by chemically plated technique on polyimide substrate at room temperature. The indacenodithiophene-co-benzothiadiazole (IDT-BT) OTFTs with chemically plated electrodes obtain the saturation mobility of 0.25 cm $^{2}\text{V}^{-1}\text{s}^{-1}$ . Furthermore, compared with high-temperature thermal evaporation method, the subthreshold swing of the IDT-BT OTFTs decreases from 1.97 to 0.89 V/dec with chemically plated Ag source/drain electrodes. The smaller threshold voltage and contact resistance are also obtained, owing to the change of work function. The bending tests indicate that the electrical properties of the devices maintain unchanged during tensile bending at a radius up to 1.4 mm. Moreover, the electrical property of the devices remains stable at a tensile bending cycle of 1000 cycles at a radius of 2.5 mm. This proposed methodology has great potential for flexible and wearable electronic devices.

In this letter, the carrier mobility of amorphous InGaZnO (a-IGZO) thin-film transistor (TFT) was remarkably enhanced by the introduction of nitrogen and the formation of Zn3N2, in which the saturation field-effect mobility ( $\mu _{\text {sat}}$ ) was 61.6 cm2/Vs. Annealing temperature plays a key role on the enhancement of carrier mobility. When the annealing temperature was increased to 400 °C, $\mu _{\text {sat}}$ was reduced to 4.1 cm2/Vs, which was proposed to be due to the formation of defective ZnxNy based on X-ray photoelectron spectroscopy results. In addition, the a-IGZO TFT with enhanced mobility did not exhibit persistent photoconductivity behavior. The high carrier mobility could expand the application of a-IGZO TFTs to functional circuits in active-matrix displays.

A modified Poisson–Boltzmann model (PBEm) can be successfully used to determine the binding strength parameter, i.e., (Henry constant, K), for the protein adsorbent interaction in ion-exchanger columns. Lysozyme has been employed as a standard protein for the adsorption in a mesoporous silica adsorbent. The density of aminoacid groups and silanol groups were used as inputs to calculate the protein charge density as a function of pH, salt concentration, and type of salt. Using the electrostatic potential provided as solving the PBEm with the protein charge surface and silanol wall as boundaries conditions, we calculated the K through the potential of mean force to describe the whole set of experimental data. The unique estimated parameter in this work was the volumetric accessible surface area from isotherm data for different electrolyte conditions. The results show that the protocol applied includes a pH and ionic strength dependence in the Langmuir isotherm. A sensibility test with different anions ( $$\text {Cl}^{-}$$ , $$\text {Br}^{-}$$ , and $$\text {I}^{-}$$ ) showed an agreement with the Hofmeister series for the protein/adsorbent interaction. A modification in the electrolyte concentration and pH can change the behavior of the isotherm profile for a fixed value of saturation capacity, independently calculated for spheres packed in cylinders. The calculations provide here can be helpful for the optimization of the best condition for protein adsorption.

This paper presents the design of a low-power electrocardiogram (ECG) readout system suitable for use in recording ECG from dry electrodes. To minimize the system’s overall power consumption, we employ a very high gain (69 dB) along with a discrete-time signal-folding technique to prevent signal saturation in the amplification stage to reduce the required resolution of the analog-to-digital converter (ADC) to only 8 bits. Fabricated in a standard 0.18- $\mu {\mathrm {m}}$ CMOS process with an active area of 1.07 mm2, the proposed readout system exhibits an input impedance exceeding $1~{\mathrm {G}} \Omega$ in a bandwidth of 0.5-150 Hz, an overall input-referred noise of $2.9~\mu {\mathrm {V}}_{{\mathrm {rms}}}$ , an input range of 12.5 mVpp, while consuming a total current of $4.5~\mu \text{A}$ from a 1.2-V supply voltage.

In this work, the biosorption behavior of acid red 27 (AR27) dye using Eichhornia crassipes leaves (LECs) in a packed-bed column was investigated by varying relevant operational parameters and assessment of mathematical models. Results showed that the zero-charge point of LECs was 2.37 and that optima pH and volumetric flux of the influent solution for AR27 biosorption were 2.0 and $$56.5\ \hbox {L}/\hbox {m}^{2}\cdot \hbox {h}$$ 56.5 L / m 2 · h , respectively. The maximum specific and volumetric biosorption capacities were observed at influent AR27 concentrations and with LEC bed heights ranging between 50 and 400 mg/L and 2 and 8 cm, respectively. It was also found that if LEC bed height was increased and volumetric flux and AR27 concentration of the influent solution decreased, service and saturation time increased. Modeling results revealed that the Thomas, bed depth service time, Yoon–Nelson, dose-response, and logistic models accurately described the dynamic performance of the packed-bed column in terms of pH, AR27 concentration, and volumetric flux of influent AR27 solution, as well as that of LEC bed height. The findings revealed that LECs exhibited remarkable potential for the biosorption of AR27 from aqueous solutions in a packed-bed column and could potentially be useful for the treatment of AR27-laden wastewater.

Trapped foam saturation ( $$S_{{\text{g}}}^{{\text{t}}}$$ ), apparent viscosity ( $$\mu { }_{{{\text{app}}}}^{{\text{f}}}$$ ), and the limiting capillary pressure of foam ( $$P_{{\text{c}}}^{*}$$ ) are the common indices used to describe foam strength in porous media. They are linearly intercorrelated when they are obtained from a single porous medium. However, $$P_{{\text{c}}}^{*}$$ is inversely correlated with $$S_{{\text{g}}}^{{\text{t}}}$$ and $$\mu { }_{{{\text{app}}}}^{{\text{f}}}$$ , when obtained from porous media with different pore structures. This paper investigates these contradictions and presents a new insight. Here, the three indices were obtained from 12 different rock samples with multiple steady-state foam injection coreflood experiments. The pore properties of the rock samples were measured with high-resolution synchrotron X-ray microtomography 3D imaging, pore network analysis, and nuclear magnetic resonance (NMR) relaxometry. Pore aspect ratio was found to offer opposing effects on $$P_{{\text{c}}}^{*}$$ relative to $$S_{{\text{g}}}^{{\text{t}}}$$ and $$\mu_{{{\text{app}}}}^{{\text{f}}}$$ , resulting in an inverse relationship between them. Hence, $$S_{{\text{g}}}^{{\text{t}}}$$ or $${\mu }_{{{\text{app}}}}^{{\text{f}}}$$ may not be an absolute index of foam strength. Rather, mobile-trapped foam ratio (ranging from 0 to 1) appears to be a more appropriate index as it correlates linearly with $$P_{{\text{c}}}^{*}$$ . A mobile-trapped foam ratio near zero indicates a very weak foam while a ratio of unity indicates a very strong foam. The ratio also correlates strongly with NMR relaxation time, making NMR log a promising tool for predicting foam strength in reservoir rocks. The graphical interpretation technique used to obtain these ratios is presented. This technique also allowed foam stability to be evaluated based on the ability of the trapped lamellae to withstand shear force during prolonged liquid flow. Based on these, different combinations of strength and stability of foam in porous media were identified namely strong and stable; strong and unstable; weak and stable, and weak and unstable foam.

This article presents results on flexible high-temperature polycrystalline silicon (FHTPS) thin-film transistor (TFT) fabricated on metal foils. Metal foils eliminate processing temperature constraints which are rather stringent on flexible TFT devices fabricated on plastics and allow high-temperature post-crystallization annealing (PCA). The source/drain (S/D) area of the devices was doped by diffusion with a spin-coated solid source at high temperatures and this process also functioned as PCA to improve the quality of the active undoped area. Solid-phase crystallized TFTs with diffused S/D at 800 °C demonstrate saturation mobility ( $\mu _{SAT}$ ) of 103 cm2/ $\text{V}\cdot \text{s}$ , an ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ratio of close to 106, a subthreshold swing (SS) of 498 mV/dec, and a threshold voltage ( ${V}_{TH}$ ) of 4.9 V. Technology computer-aided design (TCAD) simulations reveal that parasitic resistance accounts for most of the performance variations of devices diffused at different temperatures when the devices are turned on, and defect density is dominant in the subthreshold and the off regimes. The performance of the fabricated devices suffered only slight changes after 10 000 cycles of bending with 7 mm radius showing their mechanical robustness.

Metal-insulator-semiconductor field-effect transistors (MISFETs) with high-k HfNx multilayer gate dielectrics fabricated with Si surface flattening process were investigated. The Si surface flattening process was carried out by Ar/1.0%H2 annealing for 30 min. A higher $\text{I}_{\mathrm{ on}}/{\mathrm{ I}}_{\mathrm{ off}}$ current ratio was obtained by increasing the number of HfNx gate dielectric layers while its characteristics such as drain current, saturation mobility and subthreshold swing (SS) are not markedly degraded. This is attributed to the thicker gate dielectrics. Furthermore, it is found that these characteristics are found to be effectively improved by Si surface flattening process.

A model for evaluating thecontours of the A15 layer in $\rm Nb_{3}Sn$ wires is proposed. These borders, crucial for the correct assessment of the layer current density $ J_c$ and the volume layer pinning force $ F_p (B)$ are in fact non trivial to assess in some cases from scanning electron microscopy (SEM) polished surface images, eventually leading to non-negligible discrepancies between independent measurements reporting the same $ m-H$ or $ I_c$ values. A self-reliant method from magnetometry based (Bean) models is proposed, allowing the outer ( $ r_o$ ) and inner ( $ r_i$ ) contours of the A15 phase to be assessed. The magnetic moment of short samples of a prototype powder in tube (PIT) wire with artificial pinning centres (APC) was measured between 6.5 T ( $ H_0$ ) and 6.95 T at 4.2 K in a superconducting quantum interference device (SQUID) magnetometer, allowing the calculation of $r_{o}$ from the initial slope of $ dm/dH$ . Then, the derived function for the remanent magnetic moment $\rm m_{rem}$ is fit to the experimental data in order to derive $ r_i$ , under the condition that the saturation moment exactly matches the experimental value.

We demonstrated amber InGaN $47\times 47\,\,\mu \text{m}^{{2}}$ micro-light-emitting diodes ( $\mu $ LEDs) with the peak wavelength of 606 nm and full-width at maximum (FWHM) of 50 nm at 20 A/cm2. The amber $\mu $ LEDs exhibited a 33-nm blue-shift of the peak wavelength and obtain broader FWHMs to approximately 56 nm at 5 to 100 A/cm2. The peak on-wafer external quantum efficiency was 0.56% at 20 A/cm2. The characteristic temperature was 50–80 K at 20 to 60 A/cm2 but increased to 120–140 K at 80 to 100 A/cm2. The strong increase in the characteristic temperature from 60 to 80 A/cm2 could mainly be attributed to the saturation of the Shockley-Read-Hall non-radiative recombination at high current densities.

In this article, we present a surface-potential-based approach to model the bias-dependent effective velocity observed in AlGaN/GaN high-electron-mobility transistors (HEMTs) due to optical phonon scattering. Our model precisely reproduces the progressive decrease in the saturation velocity in GaN HEMTs with increasing gate voltages, as reported in the literature, which is predominantly due to the scattering of electrons, forming the high-density two-dimensional electron gas (2DEG), by optical phonons at high overdrive voltages. We show that this dependence differs from the traditional mobility degradation models in terms of its impact on the device current–voltage ( ${I}$ – ${V}$ ) characteristics and illustrate how the inclusion of a velocity saturation model also provides the model users with an additional handle for parameter extraction. The model is explicit and, by virtue of its Simulation Program with Integrated Circuit Emphasis (SPICE) compatibility, is readily implemented in the industry-standard Advanced SPICE Model for HEMTs (ASM-HEMTs) model and has been validated against experimental dc ${I}$ – ${V}$ and RF S-parameter measurements of an in-house GaN device.

For a group of users in $V$ where everyone observes a component of a discrete multiple random source, the process that users exchange data so as to reach omniscience, the state where everyone recovers the entire source, is called communication for omniscience (CO). We first consider how to improve the existing complexity $O(|V|^2 \cdot \text{SFM}(|V|)$ of minimizing the sum of communication rates in CO, where $\text{SFM}(|V|)$ denotes the complexity of minimizing a submodular function. We reveal some structured property in an existing coordinate saturation algorithm: the resulting rate vector and the corresponding partition of $V$ are segmented in $\alpha$, the estimation of the minimum sum-rate. A parametric (PAR) algorithm is then proposed where, instead of a particular $\alpha$, we search the critical points that fully determine the segmented variables for all $\alpha$ so that they converge to the solution to the minimum sum-rate problem and the overall complexity reduces to $O(|V| \cdot \text{SFM}(|V|))$. For the successive omniscience (SO), we consider how to attain local omniscience in some complimentary user subset so that the overall sum-rate for the global omniscience still remains minimum. While the existing algorithm only determines a complimentary user subset in $O(|V| \cdot \text{SFM}(|V|))$ time, we show that, if a lower bound on the minimum sum-rate is applied to the segmented variables in the PAR algorithm, not only a complimentary subset, but also an optimal rate vector for attaining the local omniscience in it are returned in $O(|V| \cdot \text{SFM}(|V|))$ time., Comment: 8 pages, 3 figures

In recent years $\beta $ -Ga2O3 thin films and crystals have gained attention as excellent candidates for transparent and high-power applications due to its wide band gap (4.6 – 4.9 eV) and large breakdown field (~8 mV/cm). However, $\beta $ -Ga2O3 single crystals and highly crystalline $\beta $ -Ga2O3 thin films require high temperature, long processing times and, often, expensive tools that limit integration with other technologies. Amorphous Ga2O3 has not been studied as intensely as $\beta $ -Ga2O3 and mostly metal-semiconductor-metal (MSM) structures and diodes using this material have been reported. In this paper, we discuss a simple and economical method to fabricate thin film transistors (TFTs) based on un-doped amorphous Ga2O3 thin films deposited at room temperature by magnetron sputtering. Control of the Ga2O3 thin films resistivity over a wide range is demonstrated by controlling the deposition power and pressure. The TFTs show a threshold voltage ( $\text{V}_{{\mathrm {T}}}$ ) of 0.92 V, saturation mobility ( $\mu _{{\mathrm {sat}}}$ ) of 0.511 cm2/ $\text{V}\cdot \text{s}$ and subthreshold slope (SS) of 83.62 mV/dec. More importantly, these devices have been evaluated as phototransistors, which has not been intensely studied yet. The phototransistors tested under DUV radiation exhibited a rejection ratio UV-Visible of 103 and responsivity of $10^{2}\text{A}$ /W ( $\text{V}_{{\mathrm {G}}} =0$ V) and 104 A/W ( $\text{V}_{{\mathrm {G}}} =6$ V), gain of 103, specific detectivity of 1015 Jones and a photosensitivity of 107.

In this paper, titanium nitride nanoparticles were prepared in three methods; in the first method, titanium nitride nanoparticles were prepared by the ball milling method; in the second and third methods, the nanoparticles were synthesized by the sol–gel and the co-precipitation methods. The samples were characterized by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), UV–Vis and Fourier transform infrared spectroscopies, and scanning electron microscopy (SEM), for the study of structural, chemical composition, and linear optical properties, respectively. Moreover, using scanning electron microscopy (SEM), the surface morphology of the samples was investigated. The XRD results showed the effect of calcination in ammonia atmosphere at 1000 °C, obtaining the pure TiN structure. However, because of oxidation in the ambient atmosphere, the titanium oxide phase was created, which was found by EDS spectroscopy and led to the creation of $${\text {TiN}}_{1-x}{\text {{O}}}_{x}$$ alloy with two bandgap energy. The nonlinear optical properties of TiN nanoparticles were studied via the Z-scan technique. The nonlinear optical behavior was found as a function of input pump power and concentration of the TiN nanoparticles. Moreover, the nonlinear optical behavior of the TiN nanoparticles shifts from inverse saturation absorption to saturation absorption with the increase in intensity. Overall, the results showed that the TiN nanoparticles give new potentials in nonlinear optical applications.

A phenomenological all region drain current model for boron (B) or nitrogen (N) substitution-doped bottom gated graphene field effect transistor (GFET) is developed. In this work, a self-consistent approach is utilized to obtain appropriate potential-charge relation. The effects of substitution doping such as shift in Dirac point with significant nonzero bandgap, change in carrier sheet density and mobility are explicitly captured in this model. In addition to that the semiclassical diffusive mobility is modeled extensively as a function of two predominant parameters such as interaction parameter ( ${r}_{s}$ ) and impurity concentration ( ${n}_{i}$ ). The proposed drain current model and diffusive mobility model are predicting an excellent agreement with experimental data from fabricated B-doped bottom gated GFET. B/N substitution-doped bottom gated GFETs completely suppress the bipolar behavior and exhibit significant reduction in OFF-current. And, the ON/ OFF-ratio has been enhanced significantly from 1 to $8\times 10^{4}$ as compared from undoped to 25% B-doped GFET, which makes B/N-doped GFETs well-suitable in digital applications. Also, B/N-doped GFETs enhance the saturation behavior which is highly desirable in analog/RF applications. Hence, B/N substitution doping in graphene fulfill the requirement of GFET in both analog/RF and digital applications.

Near-optimization is as sensible and important as optimization for both theory and applications. This paper concerns the near-optimal control of an avian influenza model with saturation on heterogeneous complex networks. Firstly, the basic reproduction number $ \mathcal{R}_{0} $ is defined for the model, which can be used to govern the threshold dynamics of influenza disease. Secondly, the near-optimal control problem was formulated by slaughtering poultry and treating infected humans while keeping the loss and cost to a minimum. Thanks to the maximum condition of the Hamiltonian function and the Ekeland's variational principle, we establish both necessary and sufficient conditions for the near-optimality by several delicate estimates for the state and adjoint processes. Finally, a number of examples presented to illustrate our theoretical results.

The electrical characteristics of simulated vertical gallium nitride (GaN) nanowire (NW) vacuum field emission diodes (VFEDs) and GaN NW vacuum field emission transistors (VFETs) with flat- and sharp-tip GaN NW field emitters (FEs) are presented by investigating their dependence on geometry and material parameters. For a flat-tip GaN NW VFED, the turn-on voltage ( ${V}_{\text{TO}}$ ) was decreased by decreasing the GaN NW diameter ( ${D}$ ), the anode to emitter distance ( ${d}$ ), the work function of the anode metal ( $\varphi _{\text{M}}$ ), or by increasing the GaN NW height ( ${h}$ ). Variations in doping concentration ( ${N}_{\text{D}}$ ) of the GaN NW do not impact ${V}_{\text{TO}}$ . The sharp-tip GaN NW VFEDs exhibited decreased ${V}_{\text{TO}}$ as the degree of sharpness ( ${d}_{\text{sh}}$ ) was increased from 0 to $0.5~\mu \text{m}$ . The saturation emitter current density ( ${J}_{\text{sat}}$ ) was only affected by variations in ${N}_{\text{D}}$ , and was increased for increased ${N}_{\text{D}}$ . The transfer ( ${I}_{\text{DS}}$ – ${V}_{\text{GS}}$ ) characteristics of sharp-tip VFETs exhibited reduced threshold voltage ( ${V}_{\text{TH}}$ ), increased transconductance ( ${G}_{\text{m, max}}$ ), and ON-/ OFF-current ratio, compared with the flat-tip ones. The output ( ${J}_{\text{DS}}$ – ${V}_{\text{DS}}$ ) characteristics of both types of devices showed nonlinear behavior at the low ${V}_{\text{DS}}$ regime.

In this letter, we propose a comprehensive benchmarking method to simultaneously address mobility enhancement and density-of-states bottleneck in advanced field-effect-transistors (FETs) with novel high-mobility (high- $\mu$ ) channel materials, where we focused on conventional covalent bonding semiconductors with pure and partially ionic character. This method relies only on the measured extrinsic transconductance of a long-channel FET in the saturation regime together with the source resistance, yielding the product of the effective mobility ( $\mu _{{eff}}$ ) and effective gate capacitance ( ${C}_{g\_{}{{eff}}}$ ). We tested this method in In x Ga1– x As quantum-well high-electron-mobility transistors (HEMTs) with various indium mole fractions, such as 0.53, 0.7, 0.8 and 1, as well as in Si n-FETs. We found that the In x Ga1– x As HEMTs with $\mu _{{eff}}$ over 10,000 cm2/ $\text{V}\cdot \text{s}$ at 300 K provided more than 20 times greater $\mu _{{eff}} \times {C}_{g\_{}{{eff}}}$ than Si n-FETs. More specifically, the product initially improved as ${x}$ increased, then showed a peak value of $10,300\,\,\mu \text{F}\cdot \text{V}^{-1}\cdot \text{s}^{-1}$ at ${x}$ of around 0.8, and degraded slightly beyond that composition. To verify the validness of the proposed method, we separately measured and analyzed ${C}_{g\_{}{{eff}}}$ and $\mu _{{eff}}$ using the split-CV technique, showing excellent agreement with the ones from the proposed method.

Conventionally, the multi-phase self-excited induction generators (SEIGs) have been analysed either with resistive or static resistive-inductive loads. This endeavor proposes a simple six-phase SEIG (6 $\phi$ -SEIG) topology feeding induction motors (IMs). Shunt and series capacitances provide excitation current and load voltage compensation for 6 $\phi$ -SEIG. A stationary reference frame dual dq model including non-linear saturation and cross coupling effects is integrated with IM loads for simulating 6 $\phi$ -SEIG-IM set. Sub-synchronous resonance (SSR) is associated with series compensated SEIGs. A series capacitance 2.5 times the excitation capacitance causes SSR in studied 6 $\phi$ -SEIG as starting of IMs is attempted from its terminals. SSR induces low frequency oscillations and spikes load voltage and current amplitudes. A method to overcome SSR is proposed by evaluating a critical value of series capacitance ( $C_{se,cr}$ ). Equipped with $C_{se,cr}$ and excitation capacitance the 6 $\phi$ -SEIG successfully sustains starting, no-load build-up and rated load operation of IMs. A comparison with its equivalent 3 $\phi$ counterpart reveals that 6 $\phi$ -SEIG manages reactive power more efficiently as its optimum capacitance requirement reduces by 1.9 to 3.75 times, it incurs 0.4% to 2.8% lesser %THDs in output parameters and exhibits greater operational flexibility. Experimental results are obtained on an open end winding induction machine operated as SEIG.

In this article, a nonlinear capacitance model for a large-signal compact model of partially depleted (PD) silicon-on-insulator (SOI) transistors is proposed. When the transistors are operated in the saturation and triode region, the gate–source capacitance ( $C_{\mathrm {gs}}$ ) and the gate–drain capacitance ( $C_{\mathrm {gd}}$ ) change with the gate–source voltage ( $V_{\mathrm {GS}}$ ) nonlinearly. $C_{\mathrm {gs}}$ will emerge a significant compression phenomenon in the triode region. This capacitance model adds a hyperbolic tangent function to the conventional model’s function to characterize this phenomenon. Besides, the nonlinear drain current model is obtained on the basis of a unified empirical model. To validate this improved large-signal equivalent circuit model, two different transistors are manufactured in a commercial 180-nm body-contact (BC) PD-SOI process. On-wafer measurement is implemented to obtain the experimental data. Then the calculated results of the model are compared with the measurement data. The relative root-mean-square-error (RRMSE) is less than 6.59% for output power, 9.03% for power-added efficiency (PAE), and 2.72% for the gain respectively.

To realize an ultralow-power, low-noise amplifier for bio-potential recording, we investigate three design techniques. The first technique uses a noise-efficient squeezed inverter (SQI) stage biased at the supply of the $2{V} _{\mathrm{ DSAT}}$ saturation limit. The challenge of interfacing the SQI stage with such a low supply is addressed by proposing a new capacitively-coupled chopper instrumentation amplifier (CCIA) with a low-noise DC servo loop (L-DSL) and an embedded ripple reduction loop (E-RRL). The second technique is reducing the high noise contribution of the conventional DSL. The proposed L-DSL reduces the input-referred noise (IRN) by removing the charge dividing effect. The proposed E-RRL inserted inside the gain stage cancels the offset and achieves a ripple suppression without loading the output. The CCIA is implemented using a $0.18~\mu \text{m}$ CMOS process. The measured results show that the L-DSL successfully creates a sub-Hz high-pass corner needed to block the electrode offset. The E-RRL achieves a ripple suppression of 39 dB. The CCIA achieves 32 nV/ $\surd $ Hz noise density, which is slightly increased to 38 nV/ $\surd $ Hz when the L-DSL is enabled. The integrated noise over 800 Hz bandwidth is 0.9 and 1.1 $\mu \text{V}_{\mathrm{ rms}}$ without and with the L-DSL, respectively. The mid-band gain of 39.6 dB is achieved by consuming $0.52~{\mu }\text{W}$ . These results correspond to a favorable noise efficiency factor (NEF) of 2.1 and a power efficiency factor (PEF) of 1.2.

We report a wavelength-tunable high-repetition-rate passively Q-switched fluoride fiber laser around $3~\mu \text{m}$ by using Ti3C2Tx MXene as saturable absorber (SA). The Ti3C2Tx MXene was synthesized by selectively etching aluminum layers in Ti3AlC2. The modulation depth, non-saturation loss and saturation fluence of the SA at 2866 nm were measured to be 43.10%, 25.16%, and 0.50 mJ /cm2, respectively. By introducing the Ti3C2Tx SA into a Ho3+/Pr3+ -codoped fluoride fiber, stable Q-switched pulses with a continuously tuning range of 30.8 nm (2868.4 nm-2899.2 nm) were achieved. The repetition rate was as high as 215.3 kHz with an output power of 142 mW at the wavelength of 2879.0 nm. Such compact mid-infrared Q-switched laser source with a high repetition rate is of great importance in various applications such as medicine, high-resolution photoacoustic microscopy, and remote sensing. Our work indicates that the Ti3C2Tx MXene is a promising broadband light modulator for pulsed laser sources around $3~\mu \text{m}$ .

This study aims to calculate cementation factor and water saturation exponent for fourdifferent lithological formations from different oil fields in south of Iraq and compare theresults with typical values of these reservoir parameters. The formations that being selectedfor this study are: Yamama Formation in West Quran (WQ-60 well), Zubair Formation insouth Rumaila (Ru-64 well), Nahr Umr Formation in Luhais oil field (Lu-5 well), andMishrif Formation in Tuba oil field (Tu-4 well). The cementation factor for clasticformations (Zubair and Nuhr Umr) was calculated via Wyllie (1949) and He (2005)empirical equations. It is found that the value of this parameter is estimated to be 1.1 and1.90 m for the Zubair formation using Wyllie equation and is equal to 2.4 and 1.6 m forNahr Umr Formation according to the He equation. For the carbonate formations (Yamamaand Mishrif), the cementation factor was estimated using Borai (1987) and Focke andMunn (1987) equations. This parameter was equal to 1.3 for both formations according toFocke and Munn (1978) and estimated to be 1.95 and 1.98 for Yamama and Mishrifformations according to equation developed by the Borai. The calculated saturationexponent was 2.5, 2, 2.21 and 0.5 in Zubair, Nahr Umr, Mishrif, and Yamama formations,respectively. The new calculated values were then applied in the Archi equation to estimatewater saturation. The obtained results were compared with that calculated in laboratory(from core). Results showed that Wyille equation is better than the He equation. The finalresult confirmed that Wyllie equation is more accurate than He equation for calculatingcementation factor in sandstone, while Borai equation was more accurate than Focke andMunn equations for the cementation factor in limestone rocks.

The isothermal equilibrium method was used to study the stable phase equilibria of the quinary system Li+, K+, Mg2+//Cl‒, $${{{\text{B}}}_{{\text{4}}}}{\text{O}}_{7}^{{2 - }}$$ –H2O at 273 K. The solubility data of each component in this system were measured through experiments, and the isothermal phase diagram of this system was also drawn. For the identification of the equilibrium solid phases of the invariant points, X-ray diffraction characterization was used. The projection surface of the stable phase diagram of the quinary system Li+, K+, Mg2+//Cl‒, $${{{\text{B}}}_{{\text{4}}}}{\text{O}}_{7}^{{2 - }}$$ ‒H2O at 273 K was drawn under the saturation condition of MgB4O7. The simplified dry-salt diagram has carnallite (KCl·MgCl2·6H2O) and lithium carnallite (LiCl·MgCl2·7H2O), and it contains eleven univariate solubility curves, five invariant points and seven crystallization regions corresponding to K2B4O7·4H2O, Li2B4O7·3H2O, KCl, MgCl2·6H2O, and LiCl·2H2O and double salts carnallite (KCl·MgCl2·6H2O) and lithium carnallite (LiCl·MgCl2·7H2O). In the quinary system, by comparing the area of each crystalline phase zone, lithium chloride is a highly soluble salt, therefore, in the solubility diagram, in comparison with magnesium tetraborate, it corresponds to the smallest crystallization area.

The natural soil-forming process is currently significantly impacted by human activities. Intense agricultural production intensifies the weathering and transformation processes of soil clay minerals, which were inherited from rocks and contain much potassium available to plants. A positive balance of vermiculite is a reliable diagnostic criterion of soil depletion in potassium, and therefore, monitoring of the content of this mineral is necessary to regulate soil fertility. A new method is proposed for quantitative determination of vermiculite in soils. The method is based on the ability of 2 : 1 clay minerals to selectively adsorb and fix Cs+. The procedure includes the saturation of soil exchange complex with Cs+ labeled with 137Сs. To do this, the sample is washed with CsCl solution with a trace level of 137Cs. After oven-drying at 110°C, which results in partial Cs+ fixation in the crystal lattice, the exchangeable Cs+ is replaced by $${\text{N}}{{{\text{H}}}_{4}}^{ + }$$ . The activity concentration of the fixed 137Сs is then determined by gamma spectrometry. Given a known ratio of Cs+ content to 137Cs activity concentration, the vermiculite quantity in soils is calculated from the ratio of the fixed Cs+ amount to the vermiculite interlayer exchange capacity, which is assumed to be 154 mg-equiv/100 g. Vermiculite content was determined in samples of arable soils, which have been collected in different climate zones of the European part of Russia. Among the soils, the lowest vermiculite content was found in soddy-podzolic soil (2.3 g/kg) and the highest one was detected in chernozems (26.9–28.6 g/kg). It is shown that vermiculite is also present in coarse fractions of soils (with particle size >1 µm). Among all soil samples, the highest content of vermiculite in coarse fractions was found in sandy soddy-podzolic soil (20.8% of the total content in soil), whereas this value in loamy and clay soils varied between 2.1 and 5.4%.

An ultralow-power direct-conversion Bluetooth-low-energy (BLE) receiver (RX) front-end that employs current-reuse and subthreshold techniques is presented. A stacked and self-biased low-noise amplifier (LNA) with active balun consumes $400~\mu \text{W}$ and achieves a noise figure (NF) of 3.2-dB and a high gain (programmable from 18 to 31 dB), meeting the system specifications over the process, supply voltage, and temperature (PVT) variations. The RX front-end has a measured integrated NF of 5.2 dB from 50 KHz to 1 MHz that corresponds to a sensitivity of −95.1 dBm. At an RX gain of 47 dB, IIP3 was measured at −19.7 dBm. The LC VCO operates at twice the carrier frequency with a tuning range of 4.55 to 5.15 GHz in an integer-N phase-locked loop (PLL). An ultralow-power CML divider is used to generate the LO $I/Q$ . The integrated phase noise (IPN) of the LO at 2.4 GHz is 0.83° with spot phase noise of −119.9 dBc/Hz at 3 MHz frequency offset. The PLL is entirely placed inside the VCO inductor resulting in an overall die area reduction of 8%. A 6- $\mu \text{W}$ automatic dc offset-calibrator avoids saturation of consecutive baseband blocks. Multiple $\mu \text{W}$ -level feedback control loops are used in the design to make it robust over PVT variations. The RX front-end prototype is implemented in a 40-nm LP CMOS process and occupies a silicon area of 0.7 mm 2.

We examined the effects of four stressors, irradiance, temperature, desiccation, and salinity on the photosynthesis of a red alga, Agarophyton vermiculophyllum (= Gracilaria vermiculophylla, Gracilariales, Rhodophyta) from its native distributional range in Hokkaido and Kagoshima, Japan. Photosynthesis–irradiance (P–E) curves at 8, 16, and 28°C showed that the maximum net-photosynthetic rates (NPmax) and saturation irradiance (Ek) were highest at 28°C for both strains. Gross-photosynthesis determined at 8–40°C at 200 μmol photons m-2 s-1 showed that the maximum gross-photosynthetic rate (GPmax) occurred at 25.3°C for Hokkaido and 28.0°C for Kagoshima ( $$ {T}_{opt}^{GP} $$ ), which is almost consistent with the summer-time seawater temperature at each habitat. The temperature responses (4–40°C) of effective quantum yields (ΔF/Fm') of photosystem II during 7-day exposures were similar to that of oxygenic photosynthesis and the optimum temperature ( $$ {T}_{opt}^{\varDelta F/ Fm\prime } $$ ) was 20.0°C for Hokkaido and 30.1°C for Kagoshima. In the desiccation experiment, the ΔF/Fm' decreased with decreasing absolute water content (AWC); nevertheless, for samples with an AWC above 20%, ΔF/Fm' retuned to initial levels after subsequent 1-day rehydration in seawater, suggesting relatively strong tolerance to desiccation. This alga also showed a broad range of tolerance to salinity ranging from 20 to 60 psu in 7-day exposures, and the ΔF/Fm' tolerated 0 psu at 3-day exposure. The adaptations of A. vermiculophyllum from its native range in Japan to relatively high irradiance, a broad range of temperature, and strong osmotic (desiccation and salinity) tolerance explain its potentially high invasive capacity.

The apparent saturation of aggressive Moore’s law scaling of semiconductor technologies is pushing the boundaries of traditional packaging and integration schemes to accommodate the ever-growing data bandwidth and heterogeneity demands. In this article, we demonstrate the silicon-interconnect fabric (Si-IF) technology as a superior alternative to conventional printed circuit boards (PCBs) to enhance system scaling. The Si-IF is a silicon-based, package-less, fine-pitch, highly scalable, heterogeneous integration platform to assemble and integrate massive wafer-scale systems. In this technology, dielets are closely assembled on the Si-IF at small interdielet spacings ( $\leq 50~\mu \text{m}$ ) using fine-pitch ( $\leq 10~\mu \text{m}$ ) die-to-substrate interconnects allowing for tight integration on a system-level package. To achieve these fine-pitch interconnects, a novel assembly technique using solder-less direct metal–metal [copper–copper (Cu–Cu)] thermal compression bonding was developed. Using this process, sub-10- $\mu \text{m}$ -pitch interconnects with a low specific contact resistance of $\leq 0.7~\Omega \cdot \mu \text{m}~^{\mathrm{ 2}}$ and high shear force of 90 N for 4-mm 2 dies were successfully demonstrated. Moreover, these fine-pitch interconnects combined with the small interdie spacing provide a large number of parallel short links ( $\leq 500~\mu \text{m}$ ) with low loss (≤2 dB) for interdielet communication that is comparable to on-chip connections. Consequently, simple buffers can transfer data between dies using a Simple Universal Parallel intERface for chips (SuperCHIPS) protocol at low link latency ( $23\times $ higher data bandwidth, 3– $65\times $ lower latency, and 5– $40\times $ lower energy per bit compared to existing integration schemes.

Division property-based integral attack is the generalization of integral property developed by blending saturation attack and higher-order differential attack. This attack is considered as a chosen-plaintext attack because the cryptanalyst generates a multiset of plaintext which possesses a certain division property. However, in real-world applications, it is required to find the division property of a given multiset which turns the attack into a known-plaintext attack. The problem, finding the division property of a given multiset $$\mathbb {X}$$ of size $$|\mathbb {X}|$$ with each element of n-bit, when solved on a classical computer has the time complexity of $$O(n2^n|\mathbb {X}|)$$ (fixed in both average and worst cases). In this paper, a better and comparable algorithm using quantum computing is presented along with its quantum oracle designs that can find the correct division property of a multiset in the average case time complexity of $$O \left( \log (n)2^n\sqrt{|\mathbb {X}|} \right) $$ and worst case time complexity of $$O\left( \log (n) 2^n|\mathbb {X}| \right) $$ using $$\left( n + \lceil \log |\mathbb {X}|\rceil + p \right) $$ -qubits, where p are the precision qubits required by the quantum counting subroutine.

Spin-spin interaction induced magnetization and susceptibility contributed by spins of the BiO6 octahedra in bismuthates have been calculated. Different disordered forms of exchange integral have been used with the help of a set of parameters in a model form. Using spins of Bi $\left (|\vec {S}|=\frac {3}{2}\right )$ and O $\left (|\vec {S}|=1\right )$ , we have calculated the magnetization and susceptibility numerically within the framework of the mean field theory (MFT). Low upper critical fields in bismuthates and the saturation spin dipole moment of the octahedra are related. The variation of the susceptibility with T exhibits a peak at a temperature Tm. An upturn in the experimental susceptibility as a function of T in the normal state has been explained by our numerical results.

The relaxation of tensile strain in fully depleted (FD) strained silicon-on-insulator (SSOI) by means of ion implantation is experimentally demonstrated in this work. This could enable SiGe p-channel field-effect transistors (pFETs) with high compressive strain (after ion implantation and Ge condensation) to be formed together with Si n-channel field-effect transistors (nFETs) with high tensile strain on the same substrate. From simulations in advanced technology node, 0.8% strain of nFETs and −0.9% strain of pFETs in fin structures can provide saturation drain current and peak ${G}_{\text {m}}$ enhancements of ~20%–30%. ${f}_{\text {T}}$ and ${f}_{\text {max}}$ benefit greatly from strain across the entire range of ${V}_{\text {G}}$ , with their peak values increasing significantly, thus allowing SSOI devices to meet 5G targets. In addition, forward back-bias shifts ${f}_{\text {T}}$ and ${f}_{\text {max}}$ curves toward lower $\boldsymbol \vert {V}_{\text {G}}\boldsymbol \vert $ , enabling reduced power consumption at the same high performance and providing better linearity. Hence, the ability to form highly strained nFETs and pFETs together on a common FD-SSOI substrate paves the way for it to become the ultimate high-performance complementary metal-oxide-semiconductor (CMOS) platform for 5G RF and logic circuits. The relaxation of the tensile strain is demonstrated and documented in Part I. A novel Comb-like device architecture to further enhance the SSOI electrical and RF performance is provided in Part II.

In this work, we study the intrinsic connection between target quality and performance of sputtered In-Sn-Zn-O (ITZO) thin-film transistors. Using a dense target, the ITZO device overall performance can be improved synergistically. The optimized device exhibits a steep subthreshold swing of 0.13 V/decade, a high on/off current ratio of $2.47\times 10^{{8}}$ , a threshold voltage of −0.03 V, a saturation field-effect mobility ( $\mu _{{FE}}$ ) of 36.1 cm2/Vs, and a small threshold voltage shift ( $\Delta ~{V} _{{th}}$ ) of −0.55 V under negative bias stress (−20 V, 3600 s). In contrast, the $\mu _{{FE}}$ shows a reverse trend to $\Delta {V} _{{th}}$ when using a target with a relatively small density and poor crystallinity. In this case, although the amount of oxygen vacancy in the films can be reduced for better stability via increasing the sputtering power, the film density observably drops due to serious preferential sputtering, leading to smaller $\mu _{{FE}}$ .

This manuscript is concerned with the Keller-Segel-Stokes system (⋆) { n t + u ⋅ ∇ n = Δ n − ∇ ⋅ ( n F ( | ∇ c | 2 ) ∇ c ) , c t + u ⋅ ∇ c = Δ c − c + n , u t = Δ u + ∇ P + n ∇ Φ , ∇ ⋅ u = 0 , under no-flux/no-flux/Dirichlet boundary conditions in smoothly bounded three-dimensional domains, with given suitably regular functions F and Φ. Here in accordance with recent developments in the literature on refined modeling of chemotactic migration, the introduction of suitably decaying F is supposed to adequately account for saturation mechanisms that limit cross-diffusive fluxes near regions of large signal gradients. In the context of such nonlinearities which suitably generalize the prototype given by F ( ξ ) = K F ( 1 + ξ ) − α 2 , ξ ≥ 0 , with K F > 0 , known results addressing a fluid-free parabolic-elliptic simplification of (⋆) have identified the value α c = 1 2 as critical with regard to the occurrence of blow-up in the sense that some exploding solutions can be found when α 1 2 , whereas all suitably regular initial data give rise to global bounded solutions when α > 1 2 . The intention of the present study consists in making sure that the latter feature of blow-up prevention by suitably strong flux limitation persists also in the more complex framework of the fully coupled chemotaxis-fluid system (⋆). To achieve this, as a secondary objective of possibly independent interest the manuscript separately establishes some conditional bounds for corresponding fluid fields and taxis gradients in a fairly general setting that particularly includes the subsystem of (⋆) concerned with the evolution of ( c , u , P ) . These estimates relate respective regularity features to certain integrability properties of associated forcing terms, as in the context of (⋆) essentially represented by the quantity n. The application of this tool to the specific problem under consideration thereafter facilitates the derivation of a result on global existence of bounded classical solutions to (⋆) for widely arbitrary initial data actually within the entire range α > 1 2 , and by means of an argument which appears to be significantly condensed when compared to reasonings pursued in previous works concerned with related problems.

We report one-volt TiO2 thin film transistors (TFTs) with a low-temperature fabrication process. The TFTs with the 300 °C-annealed TiO2 channel exhibit a high on/off current ratio ( $\text{I}_{ \mathrm{\scriptscriptstyle ON}}/\text{I}_{ \mathrm{\scriptscriptstyle OFF}})$ of $5.4\times 10^{7}$ , a low subthreshold swing (SS) of 75 mV/dec and a saturation field effect mobility ( $\mu _{{\mathrm {sat}}}$ ) of 2.13 cm $^{2}\cdot V^{-1}\cdot s^{-1}$ under an ultra-low voltage of 1 V. In contrast, the TFTs with the 200 °C-annealed TiO2 channel show no appreciable currents. Such a distinct conductivity difference is attributed to the crystallinity transformation of stoichiometric TiO2, the charge transport of which can be well explained by the multiple-trapping-and-release (MTR) model. The channel/dielectric interfaces of these one-volt TiO2 TFTs are further investigated by transmission electron microscopy (TEM), multi-frequency ( ${f}$ ) capacitance-voltage (C-V), and conductance-voltage (G-V) measurements. The interface trap density ( $\text{D}_{{\mathrm {it}}}$ ) values of $\sim 5\times 10^{12}$ cm $^{-2}\cdot {\mathrm {eV}}^{-1}$ obtained from both C-V and G-V measurements are in good agreement, suggesting a high-quality channel/dielectric interface. These one-volt TiO2 TFTs show a great potential in emerging applications, such as foldable displays and wearable sensors, where a battery-powered operation is required.

We determined the effects of irradiance, temperature, and desiccation on the photosynthesis of a brown alga, Sargassum muticum (Fucales), from its native distributional range in Japan by using a pulse amplitude modulation (PAM)-chlorophyll fluorometer and optical dissolved oxygen sensors. Photosynthesis–irradiance curves at three temperatures (8, 20, and 28°C) showed that the maximum net photosynthetic rates (NPmax) and saturation irradiance were highest at 28°C. Gross photosynthesis determined at 8–36°C (every four increments) and 300 μmol photons m−2 s−1 showed that the maximum gross photosynthetic rate (GPmax) occurred at 19.5°C ( $$ {T}_{\mathrm{opt}}^{\mathrm{GP}} $$ ), which is consistent with the seawater temperature at its peaked abundance in Japan. The maximum quantum yields (Fv/Fm) of photosystem II (PSII) during the 72-h temperature exposures were above 0.60 at 8–28°C but dropped at higher temperatures. Continuous exposure (12 h) to irradiance of 200 (low) and 1000 (high) μmol photons m−2 s−1 at three temperatures showed remarkable decline in the effective quantum yields (ΔF/Fm') of PSII under high irradiance at 8°C only; the Fv/Fm measured after 12-h dark acclimation also did not recover to initial values, signifying its sensitivity to photoinhibition at 8°C. Furthermore, the alga exhibited tolerance to 2 h of desiccation with 80% of water loss from the thallus, and ΔF/Fm' recovered after 24 h of rehydration in seawater, suggesting potential of photosynthetic recovery of this alga at such low hydration threshold. In conclusion, the adaptation of S. muticum to relatively high irradiance, to broad range of temperature (8–28°C), and to desiccation explains its potentially high invasive capacity.

We report the fluorine (F) doping effect on zinc oxide (ZnO) thin-film transistor (TFT) fabricated by spray pyrolysis on spray-coated zirconia alumina oxide (ZAO) gate insulator. F doping was performed by NF3 plasma treatment on ZnO thin film. The ZnO film shows ${C}$ -axis-aligned hexagonal structure, which remains unchanged by F doping. The photoluminescence (PL) spectra and X-ray photoelectron spectroscopy (XPS) show a reduction in oxygen-related defects by F doping. Valance band edge XPS spectra show the shift of Fermi energy level from 2.46 to 3.12 eV which reveals that the more carriers are generated in the conduction band and defect states are reduced. The F-doped ZnO (F:ZnO) TFT exhibits the saturation mobility of 31.59 cm2V−1s−1, the subthreshold swing of 238mV/dec, ON/ OFF current ratio of ~108, and zero hysteresis voltage. The F:ZnO TFT also shows significant improvement of threshold voltage shift ( $\Delta \text{V}_{TH}$ ) under negative/positive gate bias stress compared to pristine ZnO. The enhancement of mobility and stability is attributed to the substitution of oxygen (O) and passivation of oxygen vacancies ( ${V}_{o}$ ) by F in ZnO. Therefore, it is expected that F doping is an effective method to improve the performance and stability of solution-processed oxide TFTs.

In this article, a new metal-semiconductor field-effect transistor (MESFET) is introduced by amending the carrier distribution in the active regions of the device for radio frequency applications (RF). A quasi-two-dimensional material beta gallium oxide ( ${\beta }$ -Ga2O3) semiconductor is used as a fundamental material. To amend the carrier distribution, a tunnel diode (TD- ${\beta }$ GO) is employed at the bottom of the source and the channel regions in the buried oxide (BOX) layer of MESFET. In our work, parameters such as the breakdown voltage, the self-heating effect, the kink effect, the parasitic capacitance, the power gains, the noise figure, and the carrier’s concentration are obtained and compared with the conventional structure. As a result of employing the tunnel diode, the TD- ${\beta }$ GO MESFET has better characteristics in comparison with the C- ${\beta }$ GO MESFET though the drain current at the saturation region in the TD- ${\beta }$ GO structure is reduced.

This brief presents a new design methodology of single-chip reconfigurable CMOS RF power amplifier (PA) supporting both dual-band and multi-power-mode operation. The proposed architecture utilizes a novel switched-capacitor based output network to facilitate differential signal combining and impedance transformation at two widely separated frequency bands. It can offer three distinct output power levels (saturation) to be selected for multi-power-mode applications. Besides, closed-form explicit equations are readily available for the evaluation of component values. For verification, a PA operating at 1.8/2.6 GHz (non-concurrent), with three distinct saturation power levels (21, 23, 26 dBm) and peak efficiency of about 30%, is designed and fabricated using $0.35~{\mu }\text{m}$ CMOS process.

The dynamic inverter using amorphous indium-gallium-zinc oxide thin-film transistors (a-IGZO TFTs) is revealed to be more robust to tensile strain than the static inverter that is most widely used in TFT circuits. The results with the inverters can be reasonably extended to NAND or NOR gates, because all of them are commonly composed of pull-up and pull-down networks. The experimental results after tensile bending up to 20 000 times with a bending radius of 1.5 mm show that $\Delta \text{V}_{{\text {OH}}}$ and $\Delta \text{V}_{{\text {OL}}}$ in the dynamic inverter decrease to 85% and 0% of those in the static inverter, respectively. Also, while the power consumption of the static inverter increases by 36%, which is tens of $\mu \text{A}$ , the dynamic inverter maintains low-power consumption, which is tens of nA. It is also worth noting that ratioed design and TFT operation in the saturation region make the circuit more sensitive to tensile strain than ratio-less design and TFT operation in the triode region.

In this article, we demonstrate normally-OFF p-GaN gate high electron mobility transistors (HEMTs) on Si with an ultrahigh breakdown voltage ( ${V}_{BR}$ ) and excellent saturation drain current. Benefiting from the optimized material growth of high-resistivity buffer, effective Al2O3 surface passivation with suppressed OFF-state leakage current, and proper management of the electric field on the p-GaN gate edge, the device with a gate–drain distance of $18.5~\mu \text{m}$ exhibits a ${V}_{BR}$ of 1344 V at ${I}_{D}$ of $1~\mu \text{A}$ /mm with grounded substrates, the highest among all the reported normally-OFF GaN-on-Si transistors. Well-restored high-density 2-D electron gas and efficient gate modulation enable the device with a high ${I}_{DS,max}$ of 450 mA/mm and a low specific ON-resistance of 3.92 $\text{m}\Omega \cdot $ cm2. Moreover, a large threshold voltage of 1.6 V (at ${I}_{D}$ of $10~\mu \text{A}$ /mm) and a steep subthreshold slope of 66 mV/dec have been achieved, with negligible threshold voltage shift upon long-term forward gate stress at 150 °C. These results illustrate the great potential of p-GaN gate HEMTs on Si for beyond 600-V applications.

This paper investigates the event-based fault detection (FD) problem for a category of discrete-time interval type-2 fuzzy systems with measurement outliers. For the sake of decreasing the utilization of limited communication bandwidth, an event-based mechanism is introduced. Based on the saturation function technique, a novel event-based FD observer is first designed to reduce the influence of outliers in the dynamic systems. Then, on the basis of Lyapunov stability theory, sufficient conditions are provided to ensure that the error system satisfies the \begin{document}$ \mathcal{H}_{\infty} $\end{document} performance and the \begin{document}$ \mathcal{H}_{\infty} $\end{document} fault performance in different cases, respectively. In contrast to the existing event-based FD results, the false alarm, which is induced by measurement outliers, can be effectively avoided by the designed FD observer with saturation function. Lastly, some simulation results are given to verify the effectiveness of the method presented in this paper.

In this study, we report high-performance amorphous Ga2O3 metal-oxide (AMO) thin film transistor (TFT) using an low-temperature solution-process coupling with In alloy engineering. In doping can lower the activation temperature of gallium oxide and increase the oxygen vacancy concentration to further activate the device. The optical bandgap of IGO film can be changed from 5.3 to 4.25 eV with the In doping concentration ( $\text{C}_{\mathrm{ In}}$ ) increasing from 0 % to 50 %. All TFTs with IGO channels exhibit n-type transistor characteristics and the evolution of their key electrical parameters with the In-dopant is well elucidated by the structural and morphological characterization. With the increase of $\text{C}_{\mathrm{ In}}$ , the performance of the device becomes better. Finally, a saturation field-effect mobility of 3.63 cm2V−1s−1, a current on/off ratio of 106, and a threshold voltage of 2.5 V are achieved by the In0.5Ga0.5O ( $\text{C}_{\mathrm{ In}}= 50$ %) based device. The In0.5Ga0.5O TFT also demonstrates good bias stress stability. Under the action of 20 V and −20 V gate bias for 3000 s, the ${\Delta }\text{V}_{\mathrm{ TH}}$ is +2.27 V and −1.95 V, respectively.

We performed a quantitative study using a trap-limited conduction method to correlate the density of localized states with the performance of Sm2O3- and HfO2-gated metal-oxide thin-film transistors (TFTs) fabricated at room temperature. We found that TFT performance with a Sm2O3 gate dielectric exceeds that with a HfO2 gate dielectric. Sm2O3-gated TFTs with an In-Ga-Zn-O (In-Zn-O) channel show a saturation mobility of 57.1 (114.9) cm $^2$ V $^{-1}$ s $^{-1}$ , effective threshold voltage of 0.9 (1.6) V, and subthreshold swing of 0.116 (0.256) Vdec $^{-1}$ . Based on a trap-limited conduction model, the improved performance correlates with the lower density of localized states in the tail and deep regions. A lower density of tail states leads to higher mobility, and the lower density of deep states tends to reduce both the threshold voltage and the subthreshold swing. Using semi-empirical quantum chemistry simulations, we show that the decrease in the number of localized states is associated with the inherent characteristics of Sm cations, due to their lower electropositivity and larger ionic radius compared to Hf, which leads to less ionic distortion in the channel.

The low-temperature annealing process has a critical impact on the electrical performance of thin-film transistors (TFTs). This paper reports significant performance enhancements of TFTs using a femtosecond laser pre-annealing (FLA)-based preparation method. The solution-processed In2O3 films were fabricated by FLA at various laser irradiation times and then annealed on a hot-plate at 230 °C. When the FLA time was set to 30 s, the device exhibited high saturation mobility of 10.03 ± 0.64 cm2/Vs, $I_{\mathrm {on}}/I_{\mathrm {off}}$ of $3.4\times 10^{5}$ , low $V_{\mathrm {TH}}$ of 0.14 ± 0.64 V, and small SS of 1.44 ± 0.37 V/dec. The FLA process improved the formation of M-O lattices effectively, which led to an improvement in mobility. Furthermore, the gate-bias-stress stability and time-dependent environmental stability were improved considerably by the FLA process. These results show that high-performance In2O3 TFTs can be prepared at low temperatures using FLA-centered annealing technology. This work suggests that the FLA preparation method has tremendous potential for the fabrication of low-cost, high performance, and flexible TFT devices.

The high prevalence of the world’s population diagnosed with diabetes mellitus, with a significant number suffering from diabetic foot ulcer (DFU), has always been a global concern over the years. The rapid rise of this disease in the last decades is deemed increasingly alarming as it has left deleterious effects not only on affected patients but also on the society and nation. This paper aims to develop a reliable diagnostic tool to address the tremendous need for coordinated and efficient DFU management via prediction of transcutaneous oxygen saturation ( $\text{S}_{\mathrm {t}}\text{O}_{2}$ ) and relative blood perfusion ( $\tau$ ) in the affected limb. This system integrates the use of a multispectral imaging and laser speckle contrast imaging technique for two-dimensional (2D) mapping of tissue oxygen and blood perfusion level in ulcerated foot. Longitudinal study revealed a slightly higher mean $\text{S}_{\mathrm {t}}\text{O}_{2}$ and $\tau $ level in healed ulcer than in impaired healing, despite the data indicating no statistical significance between these two groups $\left ({{p-\textrm {value}>0.05} }\right)$ . It was observed that a mean $\text{S}_{\mathrm {t}}\text{O}_{2}$ of at least 70 % and $\tau $ value of 1.5 ( $\times 10^{3}$ ) are necessary during the proliferative phase to ensure progressive healing. Based on these findings, this study concluded that high tissue oxygenation and perfusion levels are pivotal to ensure progressive wound healing. This work provides a rationale for evaluating the healing outcomes of skin grafting procedures in diabetic ulcers based on observation of quantitative changes in blood perfusion and tissue oxygen level during its revascularization phase.

A monolithic two-section InGaAs/GaAs double quantum wells (DQWs) mode-locked laser (MLL) emitting at 1.06~\mu \text{m} is demonstrated. Stable mode locking operation is achieved up to 80 °C. The fundamental repetition rate is at 9.51 GHz with a signal-to-noise ratio (SNR) of more than 55 dB, and up to the fourth harmonic at 38.04 GHz is observed. The characteristic temperature ( T_{0} ) of the laser and the influences of absorber bias voltage on T_{0} have been systematically investigated. From our findings, T_{0} shows a two-segment feature, and is slightly affected by the absorber bias voltage for photon saturation. National Research Foundation (NRF) Published version This work was supported in part by Finance science and technology project of Hainan Province under Grant ZDYF2020036, in part by the National Natural Science Foundation of China under Grant 61964007, Grant 61774024, Grant 61864002, and Grant 62064004; in part by the Hainan Provincial Natural Science Foundation of China under Grant 2018CXTD336; in part by the National Research Foundation of Singapore under Grant NRF-CRP12-2013-04; in part by the National Key Research and Development Project under Grant 2017YFB0405100; in part by the Jilin Province Science and Technology Development Plan under Grant 20190302007GX; and in part by the Young Talents Science and Technology Innovation Project of Hainan Association for Science and Technology under Grant QCXM201810.

$${\text{MgFe}_{2}\text {O}_{4}}$$ and $$\text {ZnFe}_{2}\text {O}_{4}$$ nanoparticles have shown relatively good biocompatibility and high superparamagnetic hyperthermia value, on par with the well-studied $$\text {Fe}_{3}\text {O}_{4}$$ nanoparticles. However, different studies have reported different values of hyperthermia on both the compounds. To elucidate which compound is superior hyperthermia compound, well-crystallined and narrow size distributed $$\text {MgFe}_{2}\text {O}_{4}$$ and $$Z\text {nFe}_{2}\text {O}_{4}$$ spherical nanoparticles (16 nm diameter) were synthesized by solvothermal reflux method and studied their magnetic hyperthermia values under identical conditions. To further enhance superparamagnetic hyperthermia in $$\text {MgFe}_{2}\text {O}_{4}$$ and $$\text {ZnFe}_{2}\text {O}_{4}$$ nanoparticles, hydrodynamic diameter of nanoparticles were reduced by completely removing the long chain oleic acid surfactant monolayer on nanoparticles and ligated short chain zwitterionic dopamine sulfonate surfactant on bare nanoparticles. These nanoparticles show good aqueous colloidal stability with zeta potential of − 32 mV. The study reveals that $$\text {MgFe}_{2}\text {O}_{4}$$ nanoparticles shows higher hyperthermia value (265 W/g) than that (216 W/g) of $$\text {ZnFe}_{2}\text {O}_{4}$$ nanoparticles at 1 mg/mL concentration under 35.33 kA/m and 316 kHz field parameters. This is high value at 1 mg/mL concentration compared to literature. High hyperthermia value arises from higher saturation mass magnetization (45.5 emu/g) of $$\text {MgFe}_{2}\text {O}_{4}$$ than that (36.5 emu/g) of $$\text {ZnFe}_{2}\text {O}_{4}$$ nanoparticles. High saturation magnetization of $$\text {MgFe}_{2}\text {O}_{4}$$ results from the preferential tetrahedral sites occupation of nonmagnetic $${\text {Mg}^{2+}}$$ due to small ionic radii than $${\text {Zn}^{2+}}$$ ions. If tetrahedral magnetic sublattice is occupied by more nonmagnetic cations, the net ferrimagnetic moment increases. The samples were characterized by X-ray diffraction, infrared spectra, thermogravimetry analysis, differential scanning calorimetry, field emission scanning electron microscope, zeta potential, vibrating sample magnetometer, calorimetric hyperthermia methods.