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This paper aims to present two hysteresis-control algorithms designed for medium-frequency, direct-current, resistance-spot-welding (MFDC RSW) systems. The first proposed control algorithm (MSCHC) eliminates the short switching cycles that can occur when using the existing hysteresis-control algorithms. This control minimises the number of switching cycles that are needed to generate the selected welding current. The welding-current ripple can be high when using this control algorithm. Therefore, a second algorithm (HCRR) is presented that reduces the welding-current ripple by half.

The proposed hysteresis controllers consist of the transformer’s magnetic-flux-density hysteresis regulator and a welding-current hysteresis regulator. Therefore, the welding current must be measured and the saturation of the iron core must be detected. The proposed hysteresis controller supplies the inverter with the signals needed to generate the supply voltage for the RSW transformer, which then generates the selected welding current.

The proposed MSCHC algorithm produces the smallest possible number of switching cycles needed to generate the selected welding current. The high welding-current ripple can be reduced if the number of switching cycles is increased. The observed number of switching cycles and the welding-current ripple change if the welding resistance and/or inductance change.

The number of switching cycles can be minimised when using the first proposed control algorithm (MSCHC), and so the switching power losses can be minimised. If the welding-current ripple produced by the first control algorithm is unacceptable, the second control algorithm (HCRR) can reduce it by increasing the number of switching cycles.

This paper examines the relationships between bank switching and both customer vulnerability and consumer-oriented policies (financial education and disclosure practices).

The analysis employs microdata from the Special Eurobarometer on Financial Products and Services, for 24 European nations. It carries out a probit estimation on the factors explaining propensity of bank switching, focusing on three characteristics associated with customer vulnerability: an advanced age, low educational attainment and residence in a rural or a relatively poor region.

The authors report that the probability of bank switching is significantly lower for three groups of vulnerable customers: the elderly, the less educated and those living in deprived regions. Further the authors identify that national financial education policies and disclosure practices have no significant effects on bank switching.

Based on these results, the authors propose more targeted policies recognising customers' heterogeneity are required to increase bank switching behaviour.

This paper exploits a unique source of information on bank switching behaviour and customer characteristics across European nations. These data are complemented with information about consumer financial education policies and disclosure practices from the World Bank and geographical, market and regulatory factors at the regional and national levels. The paper contributes to two academic areas. First, it presents further evidence on heterogeneity of bank customer switching behaviour, addressed at improving the understanding of customer vulnerability in banking services. Second, it examines the efficacy of consumer-oriented policies (financial literacy and disclosure practices) in encouraging bank switching.

The purpose of this paper is to describe the application of low‐glitch current cell in a digital to analog converter (DAC) to reduce the clock‐feedthrough effect and achieve a low power consumption.

A low‐glitch current switch cell is applied in a ten‐bit two‐stage DAC which is composed of a unary cell matrix for six most significant bits and a binary weighted array for four least significant bits (LSBs). The current cell is composed of four transistors to neutralize the clock‐feedthrough effect and it enables DAC to operate in good linearity and low power consumption. The prototype DAC is being implemented in a 0.35μm complementary metal‐oxide semiconductor process. The reduction in glitch energy and power consumption has been realized by preliminary experiment and simulation.

Compared to conventional current cell, more than 15 per cent reduction of glitch energy has been obtained in this work. The DAC is estimated that differential nonlinearity is within 0.1 LSB and the maximum power consumption is 68 mW at the sampling frequency of 100 MHz.

Comparison with other conventional work indicates that the current cell proposed in this paper shows much better performance in terms of switching spike and glitch, which may come from the extra dummy transistor in cell and reduce the clock‐feedthrough effect.

Recent years have witnessed the increasingly fierce competition amongst smartphone brands. Hence, smartphone firms urge to prevent current consumers from switching to maintain market position. Based on the push–pull–mooring (PPM) framework, this study aims to explore the drivers of users' intentions to switch from their current smartphone brands.

Based on previous literature and the characteristics of the smartphone purchase, this study identified one pushing, two pulling and five mooring factors. Online questionnaires were collected to test hypotheses using the structural equation modelling approach. An additional netnography study provides further support to the hypotheses.

Results show that regret is a push factor that enhances consumers' switching intentions. Moreover, two pull factors, subjective norms and alternative attractiveness positively influence consumers' switching intentions. Finally, switching costs, emotional commitment and brand community engagement are mooring factors that negatively affect brand-switching intention, whereas consumers' variety seeking has a positive effect.

This study enriches the brand switching literature and offers significant implications for customer retention.

This study aims to drive the induction machine system with a low switching frequency.

An unconventional inverter control strategy – field-oriented predictive control (FOPC) – is presented. The strategy limits current distortion by setting a boundary circle. The voltage vector, which could keep current trajectories in boundary, is selected to obtain a low switching frequency.

A dual simulation step technique is developed to investigate the influence of sampling frequency on current distortion control and switching frequency. Current control distortion can be improved, i.e. reduced, by increasing the sampling frequency; however, the switching frequency will also increase. Such a law is discovered by the dual simulation step technique and finally verified by experiments.

A new predictive control method, FOPC, is derived from the rotor filed coordinate machine model and presented in this paper. FOPC circumvents derivative calculations, and thus avoids high-frequency noise amplification.

This paper aims to present an analysis of a hybrid high‐voltage switch based on the parallel connection of IGBT and IGCT. The proposed configuration combines the advantages of both semiconductors, resulting in substantially reduced power losses. Such energy efficient switches could be used in high‐power systems where the requirements of high switching frequency or decreased cooling systems are a major concern.

The operation principle of the switch is described and simulated. The power dissipation is estimated at different operation conditions. Further, the implementation possibilities of the proposed switch configuration in a three‐level NPC inverter are analysed. The operation with the proposed PWM control algorithm is simulated and inverter power loss distribution is estimated.

According to estimations, the proposed hybrid switch configuration allows the reduction of total losses in semiconductors by at least 50 percent. If two of these switches are used in a three‐level NPC inverter as outer switches, the total losses of the inverter are reduced by 27 percent, at the same time the losses in the most stressed semiconductor device are reduced by a factor of 2.25. Therefore, achieving higher power density is possible.

The proposed switch configuration is intended for high‐power (>500 KVA) industrial, marine and railway traction systems, such as FACTS and high power variable frequency AC drives.

The paper presents the novel energy‐efficient high‐voltage switch based on the parallel connection of commercially available IGBTs and IGCTs.

Multi‐level diode‐clamped inverters have the challenge of capacitor voltage balancing when the number of DC‐link capacitors is three or more. On the other hand, asymmetrical DC‐link voltage sources have been applied to increase the number of voltage levels without increasing the number of switches. The purpose of this paper is to show that an appropriate multi‐output DC‐DC converter can resolve the problem of capacitor voltage balancing and utilize the asymmetrical DC‐link voltages advantages.

A family of multi‐output DC‐DC converters is presented in this paper. The application of these converters is to convert the output voltage of a photovoltaic (PV) panel to regulate DC‐link voltages of an asymmetrical four‐level diode‐clamped inverter utilized for domestic applications. To verify the versatility of the presented topology, simulations have been directed for different situations and results are presented. Some related experiments have been developed to examine the capabilities of the proposed converters.

The three‐output voltage‐sharing converters presented in this paper have been mathematically analysed and proven to be appropriate to improve the quality of the residential application of PV by means of four‐level asymmetrical diode‐clamped inverter supplying highly resistive loads.

This paper shows that an appropriate multi‐output DC‐DC converter can resolve the problem of capacitor voltage balancing and utilize the asymmetrical DC‐link voltages advantages and that there is a possibility of operation at high‐modulation index despite reference voltage magnitude and power factor variations.

This study aims to propose a mathematical model for stacked multicell converters (SMCs), to be exploited in the analytic determination of natural voltage balancing dynamics of the flying-capacitor (FC) stacked multicell multilevel converters, i.e. investigations of the start-up behavior, dynamic response, and natural voltage balancing phenomenon.

The crux of the proposed strategy is based on the closed-form analytic solution derivation for the switching functions used in the switching of the SMCs operated under phase disposition (PD) and phase shifted carrier (PSC) pulse width modulation (PD-PSC-PWM) technique. Hence, the suggested approach develops an analytic solution for the Fourier series and associated Fourier coefficients pertinent to the switching functions of the SMCs by obtaining the switching instants of the PD-PSC-PWM modulator in terms of Kapteyn series when the frequency of the triangular carrier waveform (fc) and that of the sinusoidal reference waveform (fr) have an integer ratio, i.e. f _c  · f _r −1=k, k∈N.

This approach results into a model, first order differential equation based model, which can be readily developed for the SMCs with any number of levels expediting the investigation of their performance. Furthermore, by an experimental scrutiny conducted on a 4×2-cell-nine-level topology of an SMC, it is inferred that under PD-PSC-PWM modulation technique, FC voltages balance naturally for higher number of stacks and cells, therefore the natural balancing exist for high-level SMCs.

Despite the sophistication of the proposed methodology and mathematical model, this study presents an alternative approach with high potential of applicability for derivation of the multilevel converter mathematical model exploiting the Kapteyn (Bessel-Fourier) series.

Numeric computation results of the proposed analytic model for the SMCs and the simulation results as well as investigational measurements taken from 2×2-cell-five-level and 4×2-cell-nine-level experimental set-ups are presented in order to substantiate the suggested approach, derived model, and verification of natural balancing.

This article and its innovations are original.

The issue is which third-party logistics to engage, and escalating customer complaints about service quality of third-party logistics (3PL) enhances the tendency of online retailers to switch to another 3PL. The current study seeks to investigate the factors influencing the satisfaction and switching intention of 3PL services among online sellers in Malaysia.

Applying a purposive sampling method, data were gathered via an online survey among online sellers. Initially, the system gathered 418 respondents, but only 311 were useable for further analysis. Since we operationalised the measures as composites, a combination of reflective and formative measurement in the study and the study focuses on explanatory and predictive purposes, partial least squares structural equation modelling with SmartPLS 4 was applied to test the model developed.

The results indicated that conflict handling had a positive effect on satisfaction, and satisfaction had a negative relationship with the switching intention of 3PL among the online retailers. Moreover, satisfaction and customer relationship management sequentially mediated conflict handling and switching intention, whereas CRM strengthens the negative relationship between satisfaction and switching intention.

The respondents only limit to the online sellers in Malaysia which based on purposive sampling method, thus the findings cannot be generalised to another countries.

The study offers insightful information for the managers of the 3PL in crafting a better policy to avoid switching behaviour among their customers. The conflict between customers and providers is unavoidable since consumers have unlimited demand and businesses have limited resources. The findings also benefit online sellers and 3PL service providers to create attractive marketing strategies for business sustainability.

The study developed a new model for the 3PL studies using the S-O-R model in introducing conflict handling and customer relationship management as the stimulus, customer's satisfaction as an organism and switching intention as a response. The study introduced single and sequential mediators also contributes to the S-O-R theory to predict the switching intention among the online sellers towards the 3PL providers. Another important contribution, customer relationship management, was confirmed to play a moderating role to influence the relationship between satisfaction and switching intention.

The purpose of this study is to design a more flexible and larger range of the dimming circuit that achieves the independence of multiple LED strings drive and can time-multiplex the power circuit.

The state-space method is used to model the BUCK circuit working in Pseudo continuous conduction mode, analyze the frequency characteristics of the system transfer function and design the compensation network. Build a simulation platform on the Orcad PSPICE platform and verify the function of the designed circuit through the simulation results. Use Altium Designer 16 to draw the printed circuit board, complete the welding of various components and use the oscilloscope, direct current (DC) power supply and a signal generator to verify the circuit function.

A prototype of the proposed LED driver is fabricated and tested. The measurement results show that the switching frequency can be increased to 1 MHz, Power inductance is 2.2 µH, which is smaller than current research. The dimming ratio can be set from 10% to 100%. The proposed LED driver can output more than 48 W and achieve a peak conversion efficiency of 91%.

The proposed LED driver adopts pulse width modulation (PWM) dimming at a lower dimming ratio and adopts DC dimming at a larger dimming ratio to realize switching PWM dimming to analog dimming. The control strategy can be more precise and have a wide range of dimming.