Active anti-islanding schemes that are based on the injection of harmonic currents, such as the measurement of the impedance at a specific frequency or similar techniques, have been proposed for anti-islanding protection in photovoltaic (PV) systems...
This paper proposes a novel brushless synchronous machine topology that utilizes stator sub-harmonic magnetomotive force (MMF) for desirable brushless operation. The sub-harmonic MMF component that is used in this novel topology is one fourth of the...
This paper proposes a novel sub-harmonic mixing topology. Based on the proposed topology and the precise three-dimensional electromagnetic model of the Schottky barrier diode; a novel 183 GHz solid-state sub-harmonic mixer is designed and measured. B...
Piecewise-type nonlinearities, such as clutch dampers in a torsional system, induce complex nonlinear dynamic behaviors that resemble super- and sub-harmonic responses. This study focuses on investigating the sub-harmonic responses induced by piecewi...
To effectively reduce the requirement of Local Oscillator (LO) power, this paper presents the design and measurement of a biased sub-harmonic mixer working at the center frequency of 0.67 THz in hybrid integration. Two discrete Schottky diodes were p...
In this paper, a 560 GHz terahertz sub-harmonic mixer using a new half-global design method is reported. This method combines the advantages of the subdivision design method and the global design method, and greatly enhances the abilities of the opti...
This paper presents a new high-efficient three-phase brushless wound rotor synchronous machine (BL-WRSM) based on a sub-harmonic field excitation technique. In the proposed machine topology, the stator is equipped with two different three-phase windi...
A compact broadband monolithic sub-harmonic mixer is presented in a 70 nm GaAs Technology for millimeter wave wireless communication application. The proposed mixer adopts a novel multi-line coupler structure; where the two-sided coupling energy of r...
A filter-free, image-reject, sub-harmonic downconverted RoF link is proposed based on a dual-polarization quadrature phase-shift keying (DP–QPSK) modulator. At the remote antenna unit, the receiving radio frequency signal is applied to the uppe...
In this paper, a high-performance 0.34 THz sub-harmonic mixer combining two-stage reduced matching technology with an improved active circuit model is established and analyzed. The mixer’s improved active circuit model is realized by decomposin...
This paper presents a topology for the brushless operation of a wound-rotor synchronous machine based on the subharmonic excitation technique by using two sets of multi-pole windings on the armature as well as on the rotor. The armature windings cons...
This paper presents the design of terahertz 2× and 4× sub-harmonic down-mixers using Schottky Barrier Diodes fabricated in standard 0.13 μm SiGe BiCMOS technology. The 340 GHz sub-harmonic mixers (SHMs) are designed based on anti-parallel-diode-pairs...
Baroclinic wave resonance, particularly Rossby waves, has attracted great interest in ocean and atmospheric physics since the 1970s. Research on Rossby wave resonance covers a wide variety of phenomena that can be unified when focusing on quasi-stati...
Aggregated Norton’s equivalent models, with parallel impedance and current injection at different harmonic frequencies are used to model the distribution grid in harmonic studies. These models are derived based on measurements and/or prior know...
In response to economic and environmental challenges like sea-level rise, salinity intrusion, groundwater extraction, sand mining, and sinking delta phenomena, the demand for solutions to adapt to changing conditions in riverine environments has incr...
This paper offers a novel dual-mode double stator wound rotor synchronous machine for variable speed applications. The proposed motor integrates the benefits of both the traditional wound rotor synchronous machine (WRSM) and brushless wound rotor syn...
This paper proposes a vibration reduction method for fractional slot concentrated winding (FSCW) permanent magnet synchronous motors (PMSMs) by applying a four-layer winding configuration. The radial electromagnetic force (REF), particularly its low...
A wide-bandwidth current-controller is required for the fast charging and discharging of applications containing super capacitors. To accomplish this, peak current mode is generally used due to the speed of its response characteristics. On the other...
A pressure sensor, located for four months in the middle of a 1275 m-long taut deep-ocean mooring in 2380 m water depth above a seamount with sub-surface top-buoys and seafloor anchor-weight, demonstrates narrow-band spectral peaks of deterministic w...
In this paper, a high-efficiency GaN Doherty power amplifier (DPA) for 5G applications in the N78 sub-6 GHz band is introduced. The theoretical analysis of the matching networks for the peak and carrier transistors is presented, with a focus on the i...
This paper studies discontinuous quasilinear sub-elliptic systems associated with Hörmander’s vector fields under controllable and natural growth conditions. By a new
In this study, sub-harmonic displacement of nonlinear oscillations with parametric excitation is solved using a simulation method called the Differential Transformation Method (DTM). We employed this method to derive solutions of nonlinear oscillatio...
This paper proposes an optimal design method to suppress critical harmonics and improve the power factor by using passive power filters (PPFs). The main objectives include (1) minimizing the total harmonic distortion of voltage and current, (2) minim...
Subsynchronous oscillation (SSO) is a critical issue for the direct-drive permanent magnet synchronous generator (D-PMSG) based wind farm integrated to a weak onshore AC grid. To analyze the mechanism of the SSO phenomenon of D-PMSG based wind farm,...
In this paper, we present and compare two different full-band WR3.4 Sub-Harmonic Mixers (SHMs), featuring traditional GaAs and the novel low-barrier InGaAs discrete diodes. In this study, an Active Multiplier Chain (AMC) is used as a Local Oscillator...
Nonlinear optics is an important area of photonics research for realizing active optical functionalities such as light emission, frequency conversion, and ultrafast optical switching for applications in optical communication, material processing, pre...
8 September 2022
Sub-Saharan Africa (SSA) has a significant proportion of populations living in urban slum conditions, where exposure to multiple environmental stressors and social inequalities is ubiquitous. This commentary synthesizes commonalities in recent enviro...
Many borate crystals feature nonlinear optical properties that allow for efficient frequency conversion of common lasers down into the ultraviolet spectrum. Twinning may degrade crystal quality and affect nonlinear optical properties, in particular i...
The angular non-critical phase-matching (A-NCPM) second-harmonic-generation (SHG) properties of RE1xRE21−xCOB (RE1, RE2 = Y, Gd, La, Tm, Sm, and Nd) type mixed crystals including NCPM wavelength and conversion efficiency were detailedly investi...
Here, we study the possibility of exquisitely selective harmonic generation based on the concept of charge transfer plasmons (CTPs) in bridged nanoparticle assemblies. By choosing plasmonic dimer nanoantenna, as a fundamental member of the nanocluste...
Carbon-containing plasma is an attractive medium for generation of harmonics of laser pulses in the extreme ultraviolet range. We ablate two metal carbide (B4C and Cr3C2) nanoparticles and silicon carbide (SiC) nanoparticles and generate harmonics af...
Crystals of Ba2Zn(BO3)2 were grown by the top-seeded solution growth (TSSG) method. The optimum flux system for growing Ba2Zn(BO3)2 crystals was 2BaF2:2.5B2O3. The transmission spectra of a (100)-orientated crystal indicated an absorption edge of 230...
Graphene on different substrates, such as SiO
This paper presents an extensive review of nonlinear response-based radar systems. Nonlinear radars are generally used for clutter suppression purposes. These radars detect the nonlinear response generated by diodes and transistors are used as a tag...
Real-driving emissions (RDE) testing with portable emissions measurement systems (PEMS) during the type approval and in-service conformity of light-duty vehicles was recently introduced in the European Union legislation. In this paper, three PEMS wer...
With the increase in computational resources, parallel computation in neutron transport codes is inherent since it allows simulations with high spatial-angular resolution. Among the different methodologies available for the solution of the neutron tr...
We report the preparation of a 780.2 nm and 852.3 nm laser device based on single-pass periodically poled magnesium-oxide-doped lithium niobate (PPMgO:LN) bulk crystals and diode-laser-seeded fiber amplifiers. First, a single-frequency continuously t...
The stability and mechanical and thermodynamic properties of Al11RE3 intermetallics (RE = Sc, Y and lanthanide La-Lu) have been investigated by combining first-principles and Debye model calculations. It was found that the formation enthalpies of the...
In the past twenty years, the basic investigation of innovative Non-Linear Optical (NLO) crystals has received significant attention, which has built the crucial heritage for the use of NLO materials. Fundamental research is essential given the scarc...
The interval analysis is famous for its ability to deal with uncertain data. This method is useful for addressing models with data that contain inaccuracies. Different concepts are used to handle data uncertainty in an interval analysis, including a...
The niobium oxide dihalides have recently been identified as a new class of van der Waals materials exhibiting exceptionally large second-order nonlinear optical responses and robust in-plane ferroelectricity. In contrast to second-order nonlinear pr...
Nonlinear diffuse femtosecond-pulse reflectometry is introduced as a powerful experimental tool for the unambiguous characterization of polar and non-polar point symmetry groups of harmonic upconversion nanoparticles. Using intense ultrashort 40 femt...
The molecular laser-induced plasma (LIP) produced during the ablation of silver sulfide (Ag2S) was used as a medium for high-order harmonic generation in the extreme ultraviolet range. The role of LIP formation, the plasma components, and the geometr...
This paper demonstrates a significant increase in the efficiency of second-harmonic generation in a suspension of lithium niobate (LiNbO3) particles during freezing at nano and picosecond pum pulse durations. The amplification is caused by the format...
Gallium Arsenide (GaAs) Schottky technology stands out for its superior performance in terms of conversion loss for terahertz mixers at room temperatures, which establishes it as a dominant solution in receivers for high-data-rate wireless communicat...
The study of biharmonic submanifolds in Euclidean spaces was introduced in the middle of the 1980s by the author in his program studying finite-type submanifolds. He defined biharmonic submanifolds in Euclidean spaces as submanifolds whose position v...
A novel method for the direction of arrival (DOA) estimation of coherent signals under a space–time–coding metasurface (STCM) is proposed in this paper. Noticeably, the STCM can replace multi-channel arrays with a single channel, which ca...
The spectral quality of magnetic resonance spectroscopic imaging (MRSI) can be affected by strong magnetic field inhomogeneities, posing a challenge for 3D-MRSI’s widespread clinical use with standard scanner-equipped 2nd-order shim coils. To o...
Transition metal dichalcogenides (TMDs) are drawing significant attention due to their intriguing photoelectric properties, and these interesting properties are closely related to the number of layers. Obtaining layer-controlled and high-quality TMD...
Time-dependent second-harmonic generation (TD-SHG) is an emerging sensitive and fast method to qualitatively evaluate the interface quality of the oxide/Si heterostructures, which is closely related to the interfacial electric field. Here, the TD-SHG...
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