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The purpose of this paper is to present, a novel boost‐active clamp bridge single stage high‐frequency zero voltage soft‐switching‐pulse width modulation (ZVS‐PWM) inverter, which converts the utility frequency AC power into high‐frequency AC power with an embedded controller. This single stage high‐frequency inverter is composed of a single‐phase diode bridge rectifier, a non‐smoothing filter, a boost‐active clamp bridge type ZVS‐PWM high‐frequency inverter, and an induction‐heated load with planar type litz wire working coil assembly. Also, the paper discusses how to extend the soft‐switching operation ranges and improve power conversion efficiency.

The proposed converter is simulated and it is implemented using embedded controller.

It was found that the single stage high‐frequency induction heating (IH) inverter using boosted voltage function can eliminate the DC and low‐frequency components of the working coil current and reduce the power dissipation of the circuit components and switching devices.

The paper shows that the PWM HF inverter is preferred for IH, since it has reduced switching losses and switching stresses. The paper can be extended to PC‐based wireless control, which can be part of a distributed control system in major industrial heating systems.

Although unfavorable pricing errors (UPEs) cost customers billions of dollars each year, research has not yet examined customers’ reactions to UPEs. This paper aims to fill this gap by examining customers’ reactions to UPEs in terms of frequency, magnitude and the interaction between frequency and magnitude. Also, this study explores the moderated mediating role of price consciousness.

Three experimental studies were conducted to examine customers’ reactions to UPEs in terms of frequency, magnitude and the interaction between frequency and magnitude. PROCESS Model 6 and 84 along with multivariate regression analysis and MANOVA were used to test the hypotheses.

The results show that high-frequency and high-magnitude UPEs lead to increased perceived deception and dissatisfaction, resulting in a higher negative attitude toward the grocery store, decreased re-patronage intentions and increased negative word-of-mouth (NWOM). Also, results show that regardless of customers’ price consciousness level, customers display negative reactions when encountering UPEs.

This paper only investigates UPEs in the brick and mortar setting; future studies should examine UPEs in different settings.

The findings show that UPEs can cause significant problems for grocery stores. Thus, managers should take precautionary measures (e.g. constantly checking shelves) to ensure that the advertised price and the checkout price match.

This paper represents the first attempt to empirically examine the relationship between UPEs frequency and magnitude, on the one hand, and perceived deception, dissatisfaction, customer attitude, re-patronage intentions, NWOM and price consciousness on the other.

This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

Since consumers are being provided with ever‐increasing amounts of information, there is an increasing need to study the way in which they handle purchasing information. Investigates the effect of buy‐frequency on one theory of consumer decision making: Perceived Risk Theory. Survey data from 100 consumers revealed that in general perceived risk decreased as buy‐frequency increased, but only for high‐value products and services and not as much as expected. High‐value services showed considerably less risk decrease as buy‐frequency increased than did high‐value products, possibly due to their heterogeneity. Experienced purchasers place more emphasis on pre‐purchase product trial and purchasing well‐known brands for high‐value goods and store image and brand loyalty for low‐value goods, than inexperienced purchasers. Discusses the implications for perceived risk measurement as well as retailing.

The purpose of this study illustrates the morphing effects around a large-scale high-lift configuration of the Airbus A320 with two elements airfoil-flap in the take-off position. The flow around the airfoil-flap and the near wake are analysed in the static case and under time-dependent vibration of the flap trailing-edge known as the dynamic morphing.

Experimental results obtained in the subsonic wind tunnel S1 of Institut de Mécanique des Fluides de Toulouse of a single wing are discussed with high-fidelity numerical results obtained by using the Navier–Stokes multi-block (NSMB) code with advanced turbulent modelling able to capture the predominant instabilities and coherent structure dynamics. An explanation of the dynamic time-dependent grid deformation is provided, which is used in the NSMB code to simulate the flap’s trailing-edge deformation in the morphing configuration. Finally, power spectral density is performed to reveal the coherent wake structures and their modification because of the morphing.

Frequency of vibration and amplitude of deformation effects are investigated for different morphing cases. Optimal morphing regions at a specific frequency and a slight deformation were able to attenuate the predominant natural shear-layer frequency and to considerably decrease the width of the von Kármán vortices with a simultaneous increase of aerodynamic performances.

The new concept of future morphed wings is proposed for a large scale A320 prototype at the take-off position. The dynamic morphing of the flap’s trailing-edge is simulated for the first time for high-lift two-element configuration. In addition, the wake analysis performed helped to show the turbulent structures according to the organised eddy simulation model.

The purpose of this paper is to study the high-frequency impacts of fast switching wide-bandgap transistors on electronic and motor designs. The high-frequency power converters, dedicated to driving high-speed motors, require specific models to design predictively electronic and motors.

From magnetic and electric models, the high-frequency parasitic elements for both electronics and motor are determined. Then, high-frequency circuit models accounting for of parasitic element extractions are built to study the wide bandgap transistors commutations and their impacts on motor windings.

The results of the models, for electronics and motors, are promising. The high-frequency commutation cell study is used to optimize the layouts and to improve the commutation behaviours and performances. The impact of the switching speed is highlighted on the winding voltage susceptibility. Then, the switching frequency and commutation rapidity can be both optimized to increase the performance of motor and electronics. The electronic model is validated by experimentations.

The method can be only applied to the existing motor and electronic designs. It is not taken into account in an automized global high-frequency optimizer.

Helped by magnetic and electric FEA calculations where the parasitic element extractions are performed. The switching frequency and commutation rapidity can be both optimized to increase the performance of motor and electronics.

The purpose of this study is to present the state of the art for fiber Bragg grating (FBG) acceleration sensing technologies from two aspects: the principle of the measurement dimension and the principle of the sensing configuration. Some commercial sensors have also been introduced and future work in this field has also been discussed. This paper could provide an important reference for the research community.

This review is to present the state of the art for FBG acceleration sensing technologies from two aspects: the principle of the measurement dimension (one-dimension and multi-dimension) and the principle of the sensing configuration (beam type, radial vibration type, axial vibration type and other composite structures).

The current research on developing FBG acceleration sensors is mainly focused on the sensing method, the construction and design of the elastic structure and the design of a new information detection method. This paper hypothesizes that in the future, the following research trends will be strengthened: common single-mode fiber grating of the low cost and high utilization rate; high sensitivity and strength special fiber grating; multi-core fiber grating for measuring single-parameter multi-dimensional information or multi-parameter information; demodulating equipment of low cost, small volume and high sampling frequency.

The principle of the measurement dimension and principle of the sensing configuration for FBG acceleration sensors have been introduced, which could provide an important reference for the research community.

The purpose of this paper is to provide novel insights into arts consumption behaviour and patterns of communication displayed by arts consumers using Peterson’s theoretical framework, and to identify differences in the use of communication channels across arts segments.

The authors conducted an a priori market segmentation study, with two variables serving as segmentation criteria, namely, the frequency of and the variety of arts events attended. The authors tested for differences in communication patterns.

Four segments were created: low-frequency univores, low-frequency multivores, high-frequency multivores and high-frequency omnivores. They differ in their communication patterns and online behaviours, including their online activities before and after attending arts events. Printed materials and e-mail newsletters were the most effective communication channel for raising awareness of all arts consumers.

Understanding these communication patterns can help arts marketers to increase the attendance of low-frequency segments and broaden the variety of arts events attended by the univore and multivore segments. The generalisability of the findings is limited as the survey was conducted among online Australian arts consumers only.

The paper adds the dimension of arts consumption frequency to the taxonomy of omnivores and univores proposed by Peterson, which is based on the variety of consumed arts only. The paper contributes to communication and arts marketing literature by identifying key differences in communication patterns across segments of arts consumers and the most promising communication channels to engage them.

Bellows-type fluid viscous damper can be used to isolate micro vibration in high-precision satellites. The conventional model cannot describe hydraulic stiffness in the medium- and high-frequency domain of this damper. A simplified analytical model needs to be established to analyze hydraulic stiffness of the damping element in this damper.

In this paper, a bellows-type fluid viscous damper is researched, and a simplified model of the damping element in this damper is proposed. Based on this model, the hydraulic stiffness and damping of this damper in the medium- and high-frequency domains are studied, and a comparison is made between the analytical model and a finite element model to verify the analytical model.

The results show that when silicone oil has low viscosity, a model that considers the influence of the initial segment of the damping orifice is more reasonable. In the low-frequency domain, hydraulic stiffness increases quickly with frequency and remains stable when the frequency increases to a certain value; the stable stiffness can reach 106 N/m, which is much higher than the main stiffness. Excessive dynamic stiffness in the high-frequency domain will cause poor vibration isolation performance. Adding compensation bellows to the end of the original isolator may be an effective solution.

A model of the isolator containing the compensation bellows can be derived based on this analytical model. This research can also be used for dynamic modeling and vibration isolation performance analysis of a vibration isolation platform based on this bellows-type fluid viscous damper.

This paper proposed a simplified model of damping element in bellows-type fluid viscous damper, which can be used to analyze hydraulic stiffness in this damper and it was found that this damper showed stable hydraulic stiffness in the medium- and high-frequency domains.

The purpose of this study is to investigate what type of knowledge enhances the frequency of strategic renewal for organizations operating in high velocity environments. It also investigates whether strategic renewal frequency is beneficial, rather than harmful in such environments.

The study followed a two-step data collection process involving pilot interviews and an on-site survey data collection procedure. The authors first conducted face-to-face pilot interviews with 16 fashion retailers lasting 30 min to 2 h. They then tested their hypotheses by using a sample of 152 South Korean fashion retailers, as the fashion industry is a prototypical high velocity environment.

Firms that have a higher rate of strategic renewal frequency outperform those with a lower one. Moreover, the frequency of strategic renewal mitigates the ill effects of lack of legitimacy not imbued by a franchisor’s backing. Finally, firms can increase the frequency of their strategic renewal efforts by accessing knowledge from their main customers more efficiently.

The results of this study provide a refined picture of the role of knowledge acquisition efficiency and strategic renewal frequency in the pursuit of competitive advantage in high velocity environments.