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For single crystal diamond (SCD) to gain practical use in technical applications including solid state electronics, thin (< $1 ~\mu \text{m}$), doped epitaxial SCD layers with very low (<1 nm) surface roughness are required. Conventional SCD chemical mechanical polishing (CMP) processes are insufficient to meet the requirements of such applications because the material removal rate (MRR) is often characterized inappropriately, and the material removal uniformity is seldom considered. In this study, chemical vapor deposition (CVD) growth of two lightly boron doped (p-) epilayers was performed on 3° misoriented (100) high pressure high temperature substrates of 4.5 x $4.5 mm^{2}$ area. A subsequent 8-hour oxidative CMP process utilizing potassium permanganate and a novel self-leveling holder design decreased the average surface roughness from 3.83 nm and 1.57 nm to 0.20 nm and 0.16 nm for the two samples, respectively. MRRs were determined by evaluating five circular wear monitor structures in each sample by atomic force microscopy before and after the CMP process. The average MRRs were found to be 38.6 nm/hr and 37.3 nm/hr for the two samples. The purpose of this study is to demonstrate a CMP process suitable for polishing thin SCD epilayers to meet the needs of solid-state electronics applications. [ABSTRACT FROM AUTHOR]

The 245th ECS Meeting is set to take place in San Francisco from May 26-30, 2024. This gathering will bring together scientists, engineers, and researchers from various sectors to exchange research and engage in discussions on electrochemical and solid state science and technology. The event will offer a wide range of activities, including technical programming, oral presentations, poster sessions, panel discussions, tutorial sessions, short courses, professional development workshops, and exhibits. Attendees will also have the opportunity to explore the vibrant city of San Francisco, renowned for its iconic landmarks, cultural diversity, and distinct neighborhoods. The document further provides details on notable speakers, short courses, and special events that will be featured at the meeting. Additionally, it presents a comprehensive list of divisions and sessions that will cover specific topics within various fields, such as nanocarbons, corrosion, sensors, and energy conversion. [Extracted from the article]

An intriguing phenomenon of electrically active defect generation is observed in homoepitaxial β-Ga2O3 films exposed to reverse bias at elevated temperatures. In particular, heating samples up to 675 K in the course of deep level transient spectroscopy measurements, i.e., with the reverse bias and voltage pulsing applied, resulted in the generation of three new levels at ∼1, ∼1.5, and ∼2 eV below the conduction band edge (labeled as E3*, E5, and E6). The corresponding defects exhibit different thermal stabilities; E5 and E6 show stability, while E3* demonstrates a remarkable metastability—it can be generated, annealed out, and regenerated in the course of sequential temperature cycles. Combining a number of annealing tests and using different types of epitaxial materials, the levels were systematically investigated, and the most credible scenario behind the phenomenon is the evolution of already existing defect configurations provoked by the applied temperature and bias. [ABSTRACT FROM AUTHOR]

[Display omitted] • All-printed solid-state micro-supercapacitors with MWCNTs and PEDOT:PSS. • Controlled PEDOT to PSS ratio, resulting in a four-fold increase in conductivity. • Synergy of polar solvent & temperature enhance dielectric screening, PSS segregation. • Achieved 97.5% decrease in charge transfer resistance & increased areal capacitance. • 99.7% capacitance retention (6,000 cycles), and stability (10,000 bending cycles) All solid-state micro-supercapacitors (S-MSCs) are pivotal for modern wearables as they offer rapid energy storage and release, with seamless integration into small, lightweight wearables. Developing all printed S-MSCs is a cost-effective alternative to traditional S-MSCs and can potentially revolutionize wearable energy storage technologies. This manuscript presents an innovative, substrate-friendly approach to enhance the conductivity and electrochemical performance of screen-printed electrodes for S-MSCs using multi-walled carbon nanotubes (MWCNTs): PEDOT:PSS (poly(3,4-ethylene dioxythiophene): poly(styrene sulfonate)) composite ink. By incorporating various polar solvents into the ink formulation and optimizing printing and drying parameters, a four-fold increase in conductivity (5.5 × 103 S/m) was achieved. The synergy of polar solvent addition and temperature treatment on the dielectric screening, preferential solvation, and partial segregation of PSS were identified as the principal reason behind this enhancement. The optimally formulated ink was employed to create supercapacitor electrodes, demonstrating hybrid capacitive behavior with both liquid and gel electrolytes. An impressive 97.5 % decrease in charge transfer resistance (R CT) and a corresponding increase in areal capacitance and energy density were observed for these supercapacitors due to the segregation of PEDOT and PSS achieved by the synergistic effect. All printed S-MSCs were also fabricated with an impressive areal capacitance of 9.82 mF/cm2 @ 60 µA/cm2 and areal energy density of 1.964 µWh/cm2 at an areal power density of 63 µW/cm2. The fabricated S-MSCs exhibited impeccable capacitance retention of 99.7 % after 6,000 operation cycles and impressive stability upto 10,000 bending cycles, making them promising energy storage solutions for flexible and wearable devices. [ABSTRACT FROM AUTHOR]

Charge transport in a naphthalene π-stack system can exhibit switching because of variation in its redox state. We study this phenomenon in a molecular π-stack with the aim of obtaining insight into the charge transport in DNA solid-state devices. The model molecular π-stack is based on the structure of naphthalene tetracarboxylic diimide (NTCDI), which is assembled by molecular layer epitaxy (MLE). MLE enables controllable growth of two-dimensional organic frameworks featuring ordered π-stacked arrays of aromatic molecules. These molecular stacks are grown in the in-plane direction with respect to the surface and are bonded covalently to the inorganic semiconducting substrate. In this system, the reduced NTCDI acceptors form redox polarons in which the charge is shared over several molecules within the π-stack. We study the experimental conditions that are required to sustain efficient transport in this redox-capable NTCDI molecular π-stack. The transport in this redox-active system follows the behavior of the polarons. Polaron transport occurs below the HOMO–LUMO gap in a molecular system, for which either ln I ∼ −E−2/3 or I ∼ E (linear regime). We also study the case of redox blockade for the NTCDI molecular π-stack. We demonstrate that the same model (i.e., ln I ∼ −E−2/3) is applicable for transport through DNA molecules positioned between nano-electrodes. Studying the transport in a molecular π-stack enables elucidation of the phenomenon of conductivity switching, which may be responsible for the discrepancies among different transport experiments with DNA solid-state devices. We propose a generalized-effective-medium approach to describe the redox polaron transport in a molecular stack, an approach that is based on a fully compensated semiconductor model. [ABSTRACT FROM AUTHOR]

A meta-generalized gradient approximation (meta-GGA) level screened hybrid functional is developed for the solid-state electronic structure calculations. Assessment of the proposed functional for the solid-state lattice constants and bandgaps indicates that it is quite efficient in describing those properties. Specifically, the improvement in the bandgap performance of the presently proposed meta-GGA level screened hybrid functional is noticeable. From the construction point of view, the present screened hybrid functional is one step forward to the density functional screened hybrid functional rung by adding extra ingredients in its functional form. The most appealing feature of the present screened functional is that it is constructed upon an accurate semilocal functional by adopting a simple modification on the top of that functional. [ABSTRACT FROM AUTHOR]

A device concept of an electrocaloric solid-state refrigeration is presented in this paper. The core component of the device is flexural mode composite actuators, each of which is comprised of an electrocaloric layer and an elastic substrate layer bonded together. The composite actuators have an electric field induced temperature change due to the electrocaloric effect and also have large electric field induced flexural deformation due to the converse piezoelectric effect, which enables the device to bend to contact with the heat source (or heat sink) for transferring heat. An analytical model is derived by considering multi-physical couplings for an edge-clamped circular composite device, which can accurately predict the temperature change of the device as compared with the indirect approach derived from the Maxwell relation. The model shows that the temperature change is a combinatorial result from the couplings of thermal, electric, and mechanical field in the device. Moreover, the model sheds light on exploring the optimization of the solid-state refrigeration device and indicates that different thickness ratios and radius ratios of the composite actuators have a large influence on the cooling performance of the refrigerator. [ABSTRACT FROM AUTHOR]

Inherent symmetry of a quantum system may protect its otherwise fragile states. Leveraging such protection requires testing its robustness against uncontrolled environmental interactions. Using 47 superconducting qubits, we implement the one-dimensional kicked Ising model, which exhibits nonlocal Majorana edge modes (MEMs) with ℤ2 parity symmetry. We find that any multiqubit Pauli operator overlapping with the MEMs exhibits a uniform late-time decay rate comparable to single-qubit relaxation rates, irrespective of its size or composition. This characteristic allows us to accurately reconstruct the exponentially localized spatial profiles of the MEMs. Furthermore, the MEMs are found to be resilient against certain symmetry-breaking noise owing to a prethermalization mechanism. Our work elucidates the complex interplay between noise and symmetry-protected edge modes in a solid-state environment. [ABSTRACT FROM AUTHOR]

Ceramic materials are widely used as base material for composite film and high frequency resistor because of their better insulating behavior. So, a good and careful study of dielectric and conductivity parameters are required for ceramic material. Polycrystalline ceramic (Bi0.9La0.1)(Fe0.5Ti0.5)O3 (referred as BLaFTO-10 in this communication) was successfully synthesized by traditional solid state reaction method. Structural analysis done with XRD characterization, which confirms the single-phase formation of the compound at room temperature. Scanning electron microscopy is used to examine the morphological study which confirms the polycrystalline nature of the sample. EDX study confirms the formation of compound and presence of all element in the as prepared sample. In this paper focus is made on the study of dielectric measurement, conductivity and impedance analysis in a wide range of frequency (1 kHz to 1 MHz) and temperature (250C - 5000C). Ac conductivity follows the universal Jonscher's power law. Dielectric spectrum reveals the high values of dielectric permittivity and low value of tangent loss. These interesting features could be utilized for electronic applications. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of the oxygen precursor flow supplied during metalorganic chemical vapor deposition (MOCVD) of Al2O3 films on the forward bias behavior of Al2O3/GaN metal-oxide-semiconductor capacitors. The low oxygen flow (100 sccm) delivered during the in situ growth of Al2O3 on GaN resulted in films that exhibited a stable capacitance under forward stress, a lower density of stress-generated negative fixed charges, and a higher dielectric breakdown strength compared to Al2O3 films grown under high oxygen flow (480 sccm). The low oxygen grown Al2O3 dielectrics exhibited lower gate current transients in stress/recovery measurements, providing evidence of a reduced density of trap states near the GaN conduction band and an enhanced robustness under accumulated gate stress. This work reveals oxygen flow variance in MOCVD to be a strategy for controlling the dielectric properties and performance. [ABSTRACT FROM AUTHOR]

Thermite multilayered films have the potential to be used as local high intensity heat sources for a variety of applications. Improving the ability of researchers to more rapidly develop Micro Electro Mechanical Systems devices based on thermite multilayer films requires predictive modeling in which an understanding of the relationship between the properties (ignition and flame propagation), the multilayer structure and composition (bilayer thicknesses, ratio of reactants, and nature of interfaces), and aspects related to integration (substrate conductivity and ignition apparatus) is achieved. Assembling all these aspects, this work proposes an original 2D diffusion-reaction modeling framework to predict the ignition threshold and reaction dynamics of Al/CuO multilayered thin films. This model takes into consideration that CuO first decomposes into Cu2O, and then, released oxygen diffuses across the Cu2O and Al2 O3 layers before reacting with pure Al to form Al2O3. This model is experimentally validated from ignition and flame velocity data acquired on Al/CuO multilayers deposited on a Kapton layer. This paper discusses, for the first time, the importance of determining the ceiling temperature above which the multilayers disintegrate, possibly before their complete combustion, thus severely impacting the reaction front velocity and energy release. This work provides a set of heating surface areas to obtain the best ignition conditions, i.e., with minimal ignition power, as a function of the substrate type. [ABSTRACT FROM AUTHOR]

A theory has been developed for the waveguiding characteristics of dual-tunable multiferroic magnonic crystals (MCs). The crystals are constructed as periodically width-modulated microwave transmission slot-lines placed in between thin ferrite and ferroelectric films. Dispersion characteristics of the spin-electromagnetic waves (SEWs) in the investigated periodic waveguiding structure were derived using the method of approximate boundary conditions and the coupled-mode approach. The transmission-loss characteristics (TLCs) were calculated by the transfer-matrix method. The results show that the TLCs of the structures consist of pass-bands and stop-bands. The stop-bands are due to Bragg reflections in the structure. The magnetic and electric fields control the stop-band frequencies. The ferroelectric film polarization produced with the application of control voltage to the slot-line electrodes reduces its dielectric permittivity and provides up-shift of the stop-band frequencies. The most effective electric tuning is achieved in the area of the maximum hybridization of SEWs. As a result, the investigated multiferroic MCs combine the advantages of thin-film planar topology and dual tunability of magnonic band-gaps. [ABSTRACT FROM AUTHOR]

We review the conventional measuring standard for dc Hall measurements in van der Pauw configuration with particular focus on the challenges arising from a small Hall signal compared to sizable offset voltages, which is a typical scenario for many material systems, particularly low-mobility thin films. We show that the conventional approach of using a simple field-reversal technique is often unsuited to obtain reliable results, and present an improved correction scheme to extend the accessible measurement range to mobility values well below 1 cm2/(V s). We discuss procedures to limit the impact of temperature fluctuations and long stabilization times for highly resistive materials. We further address potential sources of error due to the presence of grain boundaries in polycrystalline specimen and due to multi-carrier conduction, both of which might yield low apparent Hall mobilities significantly underestimating the actual mobility. [ABSTRACT FROM AUTHOR]

An efficient two dimensional T-A formulation based approach is proposed to calculate the electromagnetic characteristics of tape stacks and coils made of second generation high temperature superconductors. In the approach, a thin strip approximation of the superconductor is used in which the superconducting layer is modeled as a 1-dimensional domain. The formulation is mainly based on the calculation of the current vector potential T in the superconductor layer and the calculation of the magnetic vector potential A in the whole space, which are coupled together in the model. Compared with previous T-based models, the proposed model is innovative in terms of magnetic vector potential A solving, which is achieved by using the differential method, instead of the integral method. To validate the T-A formulation model, it is used to simulate racetrack coils made of second generation high temperature superconducting (2G HTS) tape, and the results are compared with the experimentally obtained data on the AC loss. The results show that the T-A formulation is accurate and efficient in calculating 2G HTS coils, including magnetic field distribution, current density distribution, and AC loss. Finally, the proposed model is used for simulating a 2000 turn coil to demonstrate its effectiveness and efficiency in simulating large-scale 2G HTS coils. [ABSTRACT FROM AUTHOR]

High coercivity CoFe2O4 (CFO) thin films with large-area are very desirable for applications. Here, we report La0.7Sr0.3MnO3 (LSMO) layer decoration effects on coercivity in CFO thin films by solution processing. With LSMO layer decoration, the coercivity increases initially and then decreases with increasing LSMO layer thickness. Strain induced by the mismatched thermal expansion coefficient and magnetostrictive coefficient as well as the interfacial magnetic exchange coupling between CFO and LSMO are investigated. The room temperature out-of-plane and in-plane coercivity reached 7.6 and 4.9 kOe, respectively, are obtained, which are the highest values in solution derived CFO thin films. The improved coercivity is beneficial for applications and provides a facile route to enhance coercivity of CFO thin films through surface modification by soft magnetic layers. [ABSTRACT FROM AUTHOR]

This work investigates the role of microstructure on radiation-induced changes to the functional response of ferroelectric thin films. Chemical solution-deposited lead zirconate titanate thin films with columnar and equiaxed grain morphologies are exposed to a range of gamma radiation doses up to 10 Mrad and the resulting trends in functional response degradation are quantified using a previously developed phenomenological model. The observed trends of global degradation as well as local rates of defect saturation suggest strong coupling between ferroelectric thin film microstructure and material radiation hardness. Radiation-induced degradation of domain wall motion is thought to be the major contributor to the reduction in ferroelectric response. Lower rates of defect saturation are noted in samples with columnar grains, due to increased grain boundary density offering more sites to act as defect sinks, thus reducing the interaction of defects with functional material volume within the grain interior. Response trends for measurements at low electric field show substantial degradation of polarization and piezoelectric properties (up to 80% reduction in remanent piezoelectric response), while such effects are largely diminished at increased electric fields, indicating that the defects created/activated are primarily of low pinning energy. The correlation of film microstructure to radiation-induced changes to the functional response of ferroelectric thin films can be leveraged to tune and tailor the eventual properties of devices relying on these materials. [ABSTRACT FROM AUTHOR]

Current-voltage, capacitance-voltage-frequency characteristics, and impedance spectroscopy (IS) under conditions of reverse and forward bias are reported in Au/CdS/porous GaAs/GaAs devices. By comparing the C-V and C-f measurements, a possible existence of two depletion layers in our structure is discussed. In contrast to the typically expected parallel association of resistive and capacitive elements, an equivalent circuit is extracted from impedance plots, which employs the constant phase element and accounts for trap states and frequency dispersion. IS makes it possible not only to clarify the contribution of additional capacitive component due to the porous GaAs/GaAs interface by using an appropriate equivalent circuit model analysis but also to estimate a more reliable capacitance value of every junction in the structure. [ABSTRACT FROM AUTHOR]

The effect of a photostimulated solid state reaction was investigated in Mn doped SrTiO3 samples. Light irradiation was performed by either halogen or UV lamps in order to study the effect of the spectral composition, and the results were compared with samples prepared at the same temperatures in a conventional furnace. The obtained samples were studied by X-ray diffraction for structural characterization and by Electron Paramagnetic Resonance, which provides microscopic information about the local environment as well as the valence state of Mn ions. It was found that light irradiation significantly enhances the solid state reaction rate compared to synthesis in the conventional furnace. Moreover, it was observed that UV lamp irradiation is much more effective compared to halogen lamps. This indicates that the absorption of light with energy larger than the materials band gap plays an important role and points towards the nonthermal mechanism of the photostimulated solid state reaction. [ABSTRACT FROM AUTHOR]

The effect of a photostimulated solid state reaction was investigated in Mn doped SrTiO3 samples. Light irradiation was performed by either halogen or UV lamps in order to study the effect of the spectral composition, and the results were compared with samples prepared at the same temperatures in a conventional furnace. The obtained samples were studied by X-ray diffraction for structural characterization and by Electron Paramagnetic Resonance, which provides microscopic information about the local environment as well as the valence state of Mn ions. It was found that light irradiation significantly enhances the solid state reaction rate compared to synthesis in the conventional furnace. Moreover, it was observed that UV lamp irradiation is much more effective compared to halogen lamps. This indicates that the absorption of light with energy larger than the materials band gap plays an important role and points towards the nonthermal mechanism of the photostimulated solid state reaction. [ABSTRACT FROM AUTHOR]

A meander-like magnetic sensing element based on the giant magnetoimpedance (GMI) effect was prepared by using optical lithography and sputtering deposition techniques. The structure of the sensing element consists of layers of Permalloy (Py=Ni81Fe19), titanium (Ti), and copper (Cu) with composition [Py(100nm)/Ti(6nm)]4/Cu(400nm)/[Py(100nm)/Ti(6nm)]4. The GMI was investigated at room temperature under applied magnetic fields (H) varying in the range of ±4.0 kOe in both longitudinal and transversal geometries. The amplitude Iac and frequency f of the ac electrical current were varied in the range of 0.35-6.50mA and 0.1-20MHz, respectively. The overall dc electrical resistance of the sensing element was found to be 45.6 Ω. The sensing element yielded a GMI of 53.5% for H≃ 5.0Oe and f⊧ 7.0MHz, and the corresponding maximum average sensitivity of about 5 Ω/Oe. The sensing element was used for measuring the local Earth magnetic field (Hlocal=0.26±0.03Hlocal=0.26±0.03 Oe) yielding a value close to the one measured by using a Hall sensor probe (=0.23±0.01=0.23±0.01Oe). GMI sensors are being used in applications such as accelerometers, magnetometers, biomagnetism, magnetic compasses, traffic control, non-destructive analysis, and virus and cancer cell detection. [ABSTRACT FROM AUTHOR]

Anisotropic charge transport properties in organic semiconducting thin films of Boron Sub Phthalocyanine Chloride (Sub-Pc) have been studied by admittance spectroscopy applying a bias voltage parallel and perpendicular to the substrate. Sub-Pc long ordered structures confined in different directions induce anisotropic carrier mobility in films. The film with a thickness of 11nm exhibited carrier mobilities three orders higher along the substrate than perpendicular to it. Furthermore, AFM, Kelvin Probe, and UV-Vis spectroscopic studies corroborated the established mobilitystructure relationship. [ABSTRACT FROM AUTHOR]

We constructed a new type of light-weight, nanocarbon based thin film material having good mechanical properties, thermal stability, and electromagnetic shielding efficiency. Our method, 3D printing combined with hot pressing, is a cheap and industrially upscalable process. First a sandwich structure was created by layer-to-layer deposition of alternating 100 lm thick nanocarbon containing plastic layers and 100 lm thick pristine plastic layers, repeated as building blocks. The 3D printed samples were hot pressed to obtain thin films of 10-30 lm thickness. We used a commercial nanocarbon 3D printing filament (Black Magic). TEM investigations revealed the nanocarbon filler to be a mixture of graphene sheets, short carbon nanotubes, fishbone nanotubes, graphitic nanoparticles, and carbon black. Small-angle X-ray scattering and X-ray diffraction studies showed some amorphization of the nanocarbon filler as a consequence of the hot pressing. The nanoindentation hardness, nanoscratch hardness, and Young's modulus increase gradually by increasing the number of layers in the films, due to an increase of the amount of nanocarbon filler. Microwave absorption also increases continuously with the number of nanocarbon layers, reaching 40% for 3 nanocarbon layers. We demonstrate that unlike most conventional composites loaded with nanocarbons having pronounced dielectric properties, when the real part of permittivity Re(e) is much higher than its imaginary part Im(e) at high frequencies, a combination of 3D printing and hot pressing allows the fabrication of composites with Re e ≈ Im e in a very broad frequency range (0.2-0.6 THz). Our new 3D printed—hot pressed thin films may compete with the CVD graphene sandwiches in electromagnetic shielding applications because of their easier processability and low cost. [ABSTRACT FROM AUTHOR]

• A series of four trifluorinated complexes of Eu(III) were synthesized and characterized spectroscopically. • The emission spectra of complexes exhibit hyperintense peak at about 612 nm which is significant for their red emission. • Judd Ofelt parameters provide information about structural and chemical environment around central trivalent ion. • The band gap values show their semiconducting characteristics are responsible for their applications in photonic devices. This article presents the preparation and characterization of a series of four tris-β-diketonate Eu(III) complexes with formulation of [Eu(tfaa) 3 (L) n ], tfaa denotes the 1,1,1-trifluoroacetylacetone, L to monodentate or bidentate neutral ligand with nitrogen and oxygen as donor atom and n can be 1 and 2. The characterization of synthesized complexes was done using infrared spectroscopy, thermo-gravimetric analysis and proton NMR spectroscopy. UV–vis absorption, photoluminescence as well as time-resolved luminescence spectroscopies were also employed to examine the spectroscopic features of ternary complexes. The proton NMR and IR spectral information has suggested the bonding of organic moieties to the Eu(III) ion. The chemical shift obtained for the protons of primary and secondary moieties are shifted in an opposite direction. The band gap values (optical and electronic) suggest the semiconducting nature of prepared europium complexes. The trivalent ion centered emission is shown by all the prepared complexes on excitation under UV-light. The hypersensitive peak situated at about 612 nm responsible for red emission is corresponding to 5D 0 →7F 2 transition and found to be sensitive to the chelating environment present at around emissive ion. Red emanating europium materials have acquired significant utilization in OLEDs, flat panel displays and solid state electronics. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of pulse electron spin resonance (ESR) spectroscopy at microwave frequencies above 100 GHz is rather challenging and expensive due to the low output power of modern high-frequency solid state electronics. However, there is a number of scientific problems that require spin relaxation measurements at THz frequencies. The rapid scan ESR is an alternative technique that does not require high microwave power and still provides information on the spin relaxation times. The method takes advantage of fast sweeps of the excitation microwave frequency over the ESR line. When the frequency sweep reaches a sufficiently high rate, distinct oscillations (also called wiggles) appear in the ESR spectrum. These oscillations bear information about T2 electron spin relaxation time, which can be extracted via fitting the rapid scan spectrum using the modified Bloch equations. In this Perspective Letter, we introduce the recent advances in this technique and discuss the future steps necessary to make the THz rapid scan ESR a convenient and easy to use tool. [ABSTRACT FROM AUTHOR]

Solid state transformer (SST) is designed as a power transmission device between AC grids and DC grids. However, the power fluctuation causes unbalanced power sharing among dual active bridge (DAB) converters and large voltage fluctuations on dc buses. Here, an adaptive virtual impedance control (AVIC) strategy is proposed to improve the balance performance of SST. Adaptive virtual impedance controller gets the same dynamic response for DAB converters, which matches dynamic impedance of DAB converters. Thereby the power balance can be achieved even the load changes. Meanwhile, an adaptive feedforward control scheme is proposed to reduce the influence of load fluctuation on DC bus voltage. The adaptive feedforward scheme also considers the parameter mismatch, thereby the balance of SST will not be destroyed. Moreover, the balanced power sharing achieved by adaptive controller eliminates the difference between actual transmission power and compensation power in each rectifier, which further suppresses the intermediate capacitor voltage fluctuations. Finally, simulation and StarSim experimental results verified the correctness and effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

Fuzzy theory is the optimal method for predicting the state of an entity in dynamic situations. The fuzzy theory incorporates different linguistic variables and membership functions for estimating the state of the entity through the enforcement of the fuzzy inference engine. In MANETs, the prediction of path stability is determined to be potentially identified by deriving the benefits of fuzzy theory since it is a suitable candidate for identifying the state of the path in dynamic conditions. Fuzzy theory is more significant in exploring different possible states under path stability determination than the Gray and Markov chains. This paper presents the Adaptive Fuzzy Logic Inspired Path Longevity Factor-Based Forecasting Model(AFLIPLFFM) for accurate prediction of path stability to improve the throughput and Packet delivery ratio in the network. The AFLIPLFFM scheme first computes the IPR of mobile nodes. It then uses it as input to the fuzzy inference engine for computing the output as path stability based on the formulation of IF-THEN-based rules for triangular membership function. It also inherited the merits of the triangular membership function and Mamdani Fuzzy Inference Engine for accomplishing the objective of path stability prediction. [ABSTRACT FROM AUTHOR]

Samarium titanate (Sm2Ti2O7) is a perovskite layered structure (PLS) material with high Curie temperature (TC ​≥ ​1247 ​°C). Sm2Ti2O7 (STO) powders were synthesized by solid state reaction method by calcining the constituent powders at 1100 ​°C for 2 ​h. The average crystallite size of calcined STO powder was measured to be 61 ​nm. Circular discs of STO samples were sintered between the temperature range 1250–1450 ​°C with a soaking time of 2 ​h and sintered density was highest (>96.35% Th.) for the samples sintered at 1450 ​°C. The direct current electrical resistivity linearly decreased from 1013 to 106 ​Ω.cm during its increase in temperature from 100 to 900 ​°C. The activation energy of the STO samples were 0.38 ​± ​0.01 ​eV (Ea1) and 1.77 ​± ​0.01 ​eV (Ea2) at temperature ranges 100 to 400 ​°C and 500 to 900 ​°C, respectively. Hence, samarium titanate is a promising sensor material for high-temperature applications. [ABSTRACT FROM AUTHOR]