Third-order Component Research Articles

Laboratory study of energy transformation characteristics in breaking wave groups

The spilling-breaking waves that appear in chirped wave packets are studied in a two-dimensional wave channel. These waves are produced by superposing waves with gradually decreasing frequencies. The analysis focuses on the nonlinear characteristics, energy variation, and energy transformation during the evolution and breaking of wave groups. Ensemble empirical mode decomposition is used to analyze the non-breaking and breaking energy variations of the intrinsic mode functions (IMFs). It is found that the third-order IMF component is a source of non-breaking energy dissipation and the second-order IMF, which represents a short wave group with a relatively higher energy content, is a primary source of the energy loss caused by wave breaking. Additionally, the findings reveal that among the three waves preceding the maximum crest, the wave closest to the maximum crest carried most of the energy. When wave breaking occurs, the energy dissipation caused by the wave breaking primarily originates from that wave. After wave breaking, whether it is the first breaker or subsequent breakers, the main energy dissipation occurs in a frequency range higher than the dominant frequency. This energy loss plays a significant role in increasing the energy of free waves. Moreover, a potential link between the number of carrier waves and wave breaking phenomena has been found. As the number of carrier waves increased, both the nonbreaking and breaking energy dissipation rates exhibited an overall increasing trend. The amount of nonbreaking energy dissipation was generally more than twice the breaking energy dissipation rate. For wave groups with more carrier waves, the modulation instability plays a significant role in generating larger waves. Furthermore, an analysis of the dominant frequency variations of the wave group before wave breaking suggests that wave breaking is not a sufficient condition for a frequency downshift in the wave spectra.

Occupational stress as a mediator between organisational intelligence traits and digital government service quality: a triangulation design approach

PurposeThis paper aims to examine the mediating role of occupational stress in addressing the missing link between organisational intelligence (OI) traits and digital government service quality and propose relevant strategies in sustaining the digital government service quality whilst enhancing the psychological well-being of the service providers.Design/methodology/approachThis paper utilises a triangulation design approach to interpret the findings of the study and propose pertinent strategies. Firstly, we examined the mediating role of occupational stress in addressing the link between OI traits, and digital government service quality. Next, we examined the priority factors of OI traits and occupational stress to sustain the quality of digital government services via the Importance-Performance Map Analysis (IPMA). These findings were cross-examined with the code’s percentage generated from participants’ open-ended survey feedback on aspects that requires improvement in sustaining service quality.FindingsIn principle, occupational stress mediates the relationship between OI traits at the third-order component level and digital service quality. Analysis at the lower component level shows that the mediation effect of occupational stress is only significant in the presence of employee-oriented OI traits and “Alignment and Congruence”. Accordingly, the IPMA exhibited the importance of “Job engagement”, “Alignment and Congruence” and “Occupational Stress” in sustaining service quality. Conversely, code’s percentage analysis demonstrated the role of other insignificant traits such as “Leadership” and Appetite for Change and Knowledge Deployment’ in ensuring the sustainability of digital service quality.Originality/valueBy integrating the Organisational Model of Stress with Public Service-Dominant Logic, this paper rejuvenates the stressors utilised in a traditional work setup and widens the perspective of individual job performance to organisational level performance, to reflect the context of today’s public service delivery. We triangulated the outcome from mediation analysis, IPMA as well as open-ended feedback analysis and propose prioritisation on the aspects of “Employee-oriented traits”, “Psychological Well-being”, “Alignment and Congruence”, “Leadership” and “Appetite for Change and Knowledge Deployment” aspects for sustaining digital government service quality. Considering the significance of occupational stress in sustaining service quality in both quantitative and qualitative analysis, this paper also takes the approach of proposing a stress intervention program at the individual and organisational levels to manage the psychological well-being of the service providers.

The mediating role of occupational stress: a missing link between organisational intelligence traits and digital government service quality

PurposeThis paper aims to examine the mediating role of occupational stress in addressing the missing gap between organisational intelligence (OI) traits and digital government service quality.Design/methodology/approachBy employing multistage cluster sampling, a total of 394 responses from the Malaysian service providers at federal government agencies were obtained. For data analysis, the partial least square structural equation modelling (PLS-SEM) approach with a disjoint two-stage approach was employed to assess the proposed higher-order model. The analysis was carried out to examine how occupational stress mediates the relationship between OI traits at each component level and digital service quality.FindingsOccupational stress mediates the relationship between OI traits at the third-order component level and digital service quality. At the second-order component level, only the employee-oriented OI traits exhibit a significant indirect effect on the digital government service quality. Narrowing down to the first order component level, two OI traits, namely “Alignment and Congruence”, and “Heart” demonstrate significant indirect effects in the mediation analysis.Originality/valueBy incorporating the organisational model of stress (OMS) with public service-dominant logic (PSDL), this paper takes an approach to revitalise the stressors and individual-level performance used in a traditional work setting. Precisely, it examines how digital service quality is influenced by today's high-performing public organisation stressors (OI traits) along with non-technical element (occupational stress). More importantly, digital government service quality was examined from a less emphasised perspective, namely the supply side or service providers’ standpoint in sustaining the digital government service performance.

Parameter Determination of Coupled and Decoupled Admittance Matrix Methods of the Norton Equivalent Model for an Air Extractor

Context: Studies carried out in low voltage networks have explored the modeling of linear single-phase loads (such as motors) and non-linear ones (such as those based on power electronics). However, induction motors exhibit non-linear characteristics between voltage and current due to the saturation of their magnetic parts. Therefore, it is necessary to study induction motors in the frequency domain with a model that allows reviewing the characteristic nonlinearity of their voltage-current interaction. Methodology: This article presents the frequency domain modeling of a single-phase induction motor used as a silent air extractor (127 V, 60 Hz, 66 W), which presents a capacitive behavior (fp = 0,93 in leading) and harmonic distortion due to a third-order component (7,0%) when fed with a pure sinusoidal voltage of 127 V. Results: This work establishes the parameters of two approaches to the Norton equivalent model (coupled and decoupled admittance matrix) which are used to estimate the distorted current signal and the values ​​of consumed active and non-active power. The results show comparisons errors of P, Q, THDi, and NRMSE indices of less than 7, 4, 14, and 3%, respectively. Conclusions: The parameters of the Norton equivalent model estimated for the single-phase induction motor allow calculating the current signal with a high degree of precision. This signal exhibits nonlinear characteristics and a capacitive behavior due to the permanent presence of a capacitor aiding the start and operation of the engine.

An optimal zero‐sequence voltage injection‐based common‐mode voltage reduction pulse‐width modulation for the reduction of common‐mode voltages in both amplitude and third‐order component

An optimal zero-sequence voltage injection-based common-mode voltage reduction pulse-width modulation (CMVRPWM) for the reduction of common-mode voltages (CMVs) in both amplitude and third-order component is proposed in this paper. On the basis of general symmetrical switching patterns of CMVRPWM, a constrained mathematical programming model is established with the objective of optimizing the volt-second value of CMV in each switching period. By solving the mathematical model, the limitation of the CMV amplitude and the reduction of third-order harmonic in CMV can be achieved simultaneously, contributing to better CMV suppression and common-mode filter design in the applications of two-level voltage source inverters (2L-VSIs). The optimal zero-sequence voltage under the given target is obtained, and the calculation method of the switching pattern and modulation wave is studied. Simulation and experimental results show that the proposed method can restrict the CMV amplitude within one-sixth of the DC bus voltage, and the third-order component in CMV is effectively reduced compared with the conventional methods.

High-performance dual-band radio-over-fiber link for future 5G radio access applications

For the fronthaul between the baseband unit and the remote radio unit (RRU), radio over fiber (RoF) is promising to replace the Common Public Radio Interface in beyond fifth-generation and the sixth-generation wireless communication systems. The weight, size, and power consumption of the RRU can be greatly reduced, along with easy support for the millimeter-wave band. In this paper, a dual-band RoF link is proposed, where flexible switching between high-frequency (28 GHz) and low-frequency (3.5 GHz) RF channels is realized through polarization control. Single-sideband modulation is performed on 28 GHz signals to avoid periodic power fading during long-distance fiber transmission. By adjusting the DC bias, the third-order intermodulation distortion component in the 3.5 GHz signal is suppressed, and the spur-free dynamic range (SFDR) is improved. Experimental results show a channel isolation of above 43 dB. The link gain of the 28 GHz signal channel is flat, and the SFDR of the 3.5 GHz signal channel can reach 118.6 d B ⋅ H z 4 / 5 . In the case of RF vector signal transmission, the adjacent channel power ratio of the 3.5 GHz signal channel is optimally up to 48 dB, and the error vector magnitude is 2.9%.

General Bi-Tri Logic SPWM for Current Source Converter With Optimized Zero-State Replacement

This article proposes an optimized zero-state replacement (ZSR) method for general bi-tri logic SPWM (BTSPWM) to deal with the common-mode voltage (CMV) issue. The BTSPWM can transform the well-developed modulation strategies for voltage source converters (VSCs) into current source converter (CSC) system through the logic translation, which can utilize the analysis concepts developed for VSC. With BTSPWM, all- <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> gating signals can be generated through the logic translation, which should be replaced with the redundant zero-states to avoid open-circuit, which provides the flexibility for ZSR. Existing ZSR strategies are mainly focused on switching time minimization while the CMV excited by the replaced zero-states is not considering. To address the CMV issue, optimized ZSR methods for general BTSPWM are proposed to address the CMV while not influence the regular PWM features. With the proposed methods, both the CMV peak value and the third-order component can be effectively reduced. Moreover, the proposed method can be easily applied to a parallel CSC system due to the inherent modularity. The performances of the proposed methods have been experimentally verified on both single and parallel CSC systems.

Third-order intercepts and nonlinear distortion level investigation for pre and post multilayer pHEMTs

Investigation of the third-order intercept point, IP3 and nonlinear distortion level, NDL for pre-and post-multilayer processed GaAs pHEMTs has been accomplished by employing two-tone intermodulation distortion measurements. The third-order intercept point is a biasing, input power, frequency-dependent term, particularly related to the fundamental and third-order intermodulation distortion component and the study extended from low to high temperatures. The main findings are that the output referenced OIP3 decreased while the input referenced IIP3 increased with frequency at peak transconductance condition and the study further extended to multi-bias operation condition. Within the measured temperature range, the IP3 and NDL modified significantly following the behaviour of IMD3 distortion. This investigation of IP3 is utilized to measure how much distortion is created and referring this to the antenna input gives a straightforward strategy to decide whether or not the spec can be met. On the other hand, analysis of NDL is vital for choosing the most excellent biasing alternative with the entryway measurements of the device to create a compromise agreeing to the desired utilization.

A Resistive Degeneration Technique for Linearizing Open-Loop Amplifiers

This brief presents a linearization technique for open-loop amplifiers. It utilizes the exponential ${V}{-}{I}$ transfer of MOS transistors in weak-inversion together with a weak form of resistive degeneration. By using a specific relationship between the input transconductance and the source degeneration resistance, the amplifier is shown to have a significant reduction ( $\sim 50\times $ ) in its third-order distortion component. Based on this linearization principle, two amplifier topologies are proposed by implementing the degeneration in (a) pseudo-differential and (b) common-mode configuration. The pseudo-differential degeneration scheme allows the amplifier to achieve more than 80dB linearity for 150mV $_{\text {pp-diff}}$ input swing at the expense of 35% lower power-efficiency. The common-mode degeneration eliminates this power penalty but exhibits ~10dB worse linearity. To ensure an optimal linearity over process variation, a foreground calibration scheme is used to detect the nonlinearity. The nonlinearity correction is done by adjusting the bias current of the amplifier. The proof-of-concept amplifiers are constructed on a stripboard to demonstrate the effectiveness of the proposed linearization technique. With an input signal of 50mV $_{\rm pp{-}diff}$ , the two topologies achieve −105dB and −95dB HD3, respectively, improving the linearity of the state-of-the-art open-loop amplifiers by at least 30dB.

A Virtual Space Vector Modulation Technique for the Reduction of Common-Mode Voltages in Both Magnitude and Third-Order Component

A virtual space vector modulation technique reducing both magnitude and third-order harmonic component of the common-mode voltage (CMV) in a two-level voltage-source inverter (VSI) is proposed in this paper. The presented method employs a set of virtual space vectors constructed from original stationary space vectors to conduct modulation. Since the created virtual vectors have the lowest instantaneous and zero average CMVs, both the magnitude and third-order harmonic component of the generated CMV are reduced, contributing to better overall CMV performance and common-mode filter design in VSI applications. Three variants of the proposed modulation method using different virtual space vector combinations are presented. The concept of the virtual space vector modulation technique demonstrated with two-level inverter in this paper can also be extended to multilevel inverters. Simulation and experimental results, as well as comparisons with existing methods are provided to verify the proposed technique.

Bit Error Probability in the Presence of Third-Order Intermodulation Distortion Component from Power Amplifier of Different Mobile Systems

This paper presents an evaluation of the bit error probability in the presence of the third-order intermodulation distortion (IMD) component generated by power amplifiers for the purpose of investigating the interference among different mobile systems. This paper derives a probability density function (PDF) for the third-order IMD component since the derivation of the bit error probability in the presence of the third-order IMD component requires the PDF of the third-order IMD component. This paper concludes that the PDF of the third-order IMD component has different stochastic properties from those of thermal noise. The PDF of the third-order IMD component should be taken into account as well as that of thermal noise when deriving the bit error probability in the presence of the third-order IMD component.

Four tests of fit for the beta-binomial distribution

Tests based on the Anderson–Darling statistic, a third moment statistic and the classical Pearson–Fisher X 2 statistic, along with its third-order component, are considered. A small critical value and power study are given. Some examples illustrate important applications.

Modified elliptically polarized light Z-scan method for studying third-order nonlinear susceptibility components

The normal elliptically polarized light Z-scan method is modified by adding a quarter-wave plate and an analyzer before the detector. The normalized transmittance formulas of modified elliptically polarized light Z-scan are obtained for media with negligible nonlinear absorption. Compared with normal linearly and elliptically polarized light Z-scan methods, an increase of sensitivity by a factor of larger than 4 is achieved for the real part of third-order susceptibility component's measurements using this modified elliptically polarized light Z-scan method. The analytical results are verified by studying the real part of independent susceptibility components of CS(2) liquid. Moreover, the potential application for cross-polarized wave generation is discussed.

Optical second-harmonic and reflectance-anisotropy spectroscopy of clean and hydrogen-terminated vicinal Si(001) surfaces

Spectroscopic second-harmonic generation (SHG) and reflectance-anisotropy spectroscopy are used to probe a single-domain reconstructed stepped Si(001) surface off cut 6&#xb0; toward [110] before and after dissociative adsorption of H2 at the DB step edges. The reflectance-anisotropy spectrum and the first- and third-order Fourier components of the SHG azimuthal anisotropy exhibit broad step-induced resonant peaks near 3.1 eV that are quenched in approximate proportion to H2 dosage, suggesting that they all share a common origin in the essential electronic resonance of the DB steps. Analysis with a simplified bond-hyperpolarizability model suggests that hydrogen termination redistributes oscillator strength from the chemically active nearly vertical step dangling bond into three underlying bonds, suggesting the latter may be related to the third-order Fourier component of the SHG response.

Linearization technique using bipolar transistor at 5 GHz low noise amplifier

A CMOS low noise amplifier (LNA) used in wireless communication systems, such as WLAN and CDMA, must have low noise figure, high linearity, and sufficient gain. Several techniques have been proposed to improve the linearity of CMOS LNA circuits. The proposed low noise amplifier achieves high third-order input intercept point (IIP3) using multi-gated configuration technique, by using two transistors, the first is the main CMOS transistor, and the second is bipolar transistor in TSMC 0.18 m technology. Bipolar transistor is used to cancel the third-order component from MOS transistor to fulfill high linearity operation. This work is designed and fabricated in TSMC 0.18 m CMOS process. At 5 GHz, the proposed LNA achieves a measurement results as 16 dBm of IIP3, 10.5 dB of gain, 2.1 dB of noise figure, and 8 mW of power consumption.

Perturbative Wilson loops from unquenched Monte Carlo simulations at weak couplings

Perturbative expansions of several small Wilson loops are computed through next-to-next-to-leading order in unquenched lattice QCD, from Monte Carlo simulations at weak couplings. This approach provides a much simpler alternative to conventional diagrammatic perturbation theory, and is applied here for the first time to full QCD. Two different sets of lattice actions are considered: one set uses the unimproved plaquette gluon action together with the unimproved staggered-quark action; the other set uses the one-loop-improved Symanzik gauge-field action together with the so-called ``asqtad'' improved-staggered quark action. Simulations are also done with different numbers of dynamical fermions. An extensive study of the systematic uncertainties is presented, which demonstrates that the small third-order perturbative component of the observables can be reliably extracted from simulation data. We also investigate the use of the rational hybrid Monte Carlo algorithm for unquenched simulations with unimproved-staggered fermions. Our results are in excellent agreement with diagrammatic perturbation theory, and provide an important cross-check of the perturbation theory input to a recent determination of the strong coupling $\alpha_{\bar{\rm MS}}(M_Z)$ by the HPQCD collaboration.

Tuning of laser pulse shapes in grating-based compressors for optimal electron acceleration in plasmas.

The temporal shape (rise time, fall time, skewness) of 50-200-fs Ti:sapphire laser pulses has been controlled by appropriate adjustment of a grating-pair compressor. It was found that the skewness of the laser pulse envelope is particularly sensitive to the third-order component of the spectral phase. Introducing such a third-order phase offset by detuning the grating pair relative to the optimum pulse compression settings allowed the generation of skewed pulses. As an example of an application, these skewed pulses were used to optimize a laser-plasma electron accelerator.

Nonlinear electrostatic emittance compensation in kA, fs electron bunches.

Nonlinear space-charge effects play an important role in emittance growth in the production of kA electron bunches with a bunch length much smaller than the bunch diameter. We propose a scheme employing the radial third-order component of an electrostatic acceleration field, to fully compensate the nonlinear space-charge effects. This results in minimal transverse root-mean-square emittance. The principle is demonstrated using our design simulations of a device for the production of high-quality, high-current, subpicosecond electron bunches using electrostatic acceleration in a 1 GV/m field. Simulations using the GPT code produce a bunch of 100 pC and 73 fs full width at half maximum pulse width, resulting in a peak current of about 1.2 kA at an energy of 2 MeV. The compensation scheme reduces the root-mean-square emittance by 34% to 0.4pi mm mrad.

A Higher Order Analysis of the Factor Structure of the Myers-Briggs Type Indicator

This study examined the higher order factor structure of Form G of the Myers-Briggs Type Indicator (MBTI; K. C. Briggs & I B. Myers, 1987). A third-order component analysis of a sample (N = 926) found 2 higher order components. This higher order analysis contributes to the research literature pertaining to the generalized structure of the personality measure.

A Third-Order Component Analysis of the Myers-Briggs Type Indicator

This study examined the factor structure of Form G of the Myers-Briggs Type Indicator (MBTI). A third-order component analysis of a sample (n = 486) yielded three higher order components. Because this is the first third-order analysis of the MBTI reported in the psychological literature, these findings contribute to the research literature pertaining to the generalized structure of the popular personality instrument.