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This study aims to solve the problem that both the speed and the required driving power of electric vehicles (EVs) will change during the dynamic wireless charging (DWC) process, making it difficult to charge EVs with a constant power considering the overall efficiency of DWC system, the numbers of EVs and the power supply capacity. Therefore, this paper proposes the power control and efficiency optimization strategies for multiple EVs.

The wireless power charging system for multiple loads with a structure of double-sided LCC compensation topology is established. The expressions of optimal transmission efficiency and optimal equivalent impedance are derived. Taking the Tesla Model 3 as an example, a method to determine the number of EVs allowed by one transmitter coil and the overall charging power is proposed considering EV speed, power supply capacity, safe braking distance and overall efficiency. Then, the power control strategy, which can adapt to the changes of EV speed and the efficiency optimization strategy under different numbers of EVs are proposed.

In this paper, a method to determine the numbers of EVs allowed by one transmitter coil and the overall charging power is proposed considering EVs speed, power supply capacity, safe braking distance and overall efficiency. The accuracy of the charging power is good enough and the overall efficiency reaches a maximum of 91.79% when the load resistance changes from 5Ω to 20Ω.

In this paper, the power control and efficiency optimization strategy of DWC system for multiple EVs are proposed. Specifically, a method of designing the number of EVs and charging power allowed by one transmitter coil considering the factors of EV speed, power supply capacity, safe braking distance and overall efficiency is designed. The overall efficiency of the experiment reaches a maximum of 91.79% after adopting the optimization strategy.

Detecting O₂ gas in a confined space at room temperature is particularly important to monitor the work process of precision equipment. This study aims to propose a miniaturized, low-cost, mass-scale produced O₂ sensor operating around 30°C.

The O₂ sensor based on lanthanum fluoride (LaF₃) solid electrolyte thin film was developed using MEMS technology. The principle of the sensor was a galvanic cell H₂O, O₂, Pt | LaF₃ | Sn, SnF₂ |, in which the Sn film was prepared by magnetron sputtering, and the LaF₃ film was prepared by thermal resistance evaporation.

Through pretreatments, the sensor’s response signal to 40% oxygen concentration was enhanced from 1.9 mV to 46.0 mV at 30°C and 97.0% RH. Tests at temperatures from 30°C to 50°C and humidity from 32.4% RH to 97.0% RH indicated that the output electromotive force (EMF) has a linear relationship with the logarithm of the oxygen concentration. The sensitivity of the sensor increases with an increase in both humidity and temperature in the couple mode, and the EMF of the sensor follows well with the Nernst equation at different temperatures and humidity.

This research could be applied to monitor the oxygen concentration below 25% in confined spaces at room temperature safely without a power supply.

The relationship between temperature and humidity coupling and the response of the sensor was obtained. The nano-film material was integrated with the MEMS process. It is expected to be practically applied in the future.

The purpose of this study is to investigate the main effect of top executive smog risk perception on green innovation and to examine the mediating role of corporate social responsibility (CSR) in the positive relationship between smog risk perception and green innovation along with the moderating role of smog knowledge.

A theoretical framework is developed based on the upper echelons theory to argue that top executive smog risk perception can be closely related to green innovation. Hierarchical analysis is conducted using a sample of eight firms in China.

Hypothesis testing indicates that physical health risk perception and mental health risk perception positively affect green innovation, and that these effects are positively mediated by CSR. In addition, smog knowledge moderates the relationship between physical health risk perception and green innovation.

The findings extend current studies on green innovation by highlighting the role of top executives’ perceptions beyond studying top executives’ attributes. The findings suggest that top executives should actively respond to smog pollution and fulfill CSR.

Previous studies have suggested that top executives’ demographic characteristics are the determining factors of green innovation. This empirical paper fills a gap in the literature by exploring the impact of top executive smog risk perception on green innovation within the framework of the upper echelons theory.

When solving the cogging torque of complex electromagnetic structures, such as consequent pole hybrid excitation synchronous (CPHES) machine, traditional methods have a huge computational complexity. The notable feature of CPHES machine is the symmetric range of field-strengthening and field-weakening, but this type of machine is destined to be equipped with a complex electromagnetic structure. The purpose of this paper is to propose a hybrid analysis method to quickly and accurately solve the cogging torque of complex 3D electromagnetic structure, which is applicable to CPHES machine with different magnetic pole shapings.

In this paper, a hybrid method for calculating the cogging torque of CPHES machine is proposed, which considers three commonly used pole shapings. Firstly, through magnetic field analysis, the complex 3D finite element analysis (FEA) is simplified to 2D field computing. Secondly, the discretization method is used to obtain the distribution of permeance and permeance differential along the circumference of the air-gap, taking into account the effect of slots. Finally, the cogging torque of the whole motor is obtained by using the idea of modular calculation and the symmetry of the rotor structure.

This method is applicable to different pole shapings. The experimental results show that the proposed method is consistent with 3D FEA and experimental measured results, and the average calculation time is reduced from 8 h to 4 min.

This paper proposes a new concept for calculating cogging torque, which is a hybrid calculation of dimension reduction and discretization modules. Based on magnetic field analysis, the 3D problem is simplified into a 2D issue, reducing computational complexity. Based on the symmetry of the machine structure, a modeling method for discretized analytical models is proposed to calculate the cogging torque of the machine.

In recent years, the ongoing development and rapid popularization of mobile devices, not only has brought new forms of lifestyle but also has boomed a wide array of service contents, allowing users to engage in entertainment, study and other daily activities, in addition to business transactions. To explore the factors that affect users' continued use of mobile app software, this paper aims to take into account the utilitarian value and privacy, as well as security factors and intends to propose an integrated research model based on the information systems success (ISS) model.

The data for this study were collected via an online survey questionnaire. A total of 190 valid responses were used to examine the hypotheses in the research model. The casual model was assessed using partial least squares techniques.

The results indicated that the three quality factors (information quality, system quality and service quality) in the ISS model significantly affected satisfaction and utilitarian value. Private and security have significant negative association with utilitarian value. The results also showed that private and security did not significantly affect satisfaction. The findings also provide some directions for further research.

The results show that user's continued use of mobile app software depends upon the perceived utilitarian value and satisfaction. The quality characteristics are the three critical factors that would affect the perceived utilitarian value and satisfaction. Compared to information quality and service quality, system quality has a higher degree of positive impact, which indicates that users are more concerned about the immediate download ability and ease-of-use provided by the system. Furthermore, the research also finds that privacy and security concerns have a negative influence on the utilitarian value, showing that in the context of task-oriented IS, the perceived risk of privacy and security during the process of using mobile app software services, will negatively affect users’ perception of utilitarian value. The insights provided by this study can help mobile app developers optimize design and marketing strategies.

This study provides a better understanding of how the factors in the theories influence the continuance usage intention of life style mobile applications.

This study aims to improve the robot’s performance during interactions with human and uncertain environments.

A joint stiffness model was established according to the molecular current method and the virtual displacement method. The position and stiffness coordination controller and fuzzy adaptive controller of variable stiffness joint are designed, and the principle prototype of variable stiffness joint is built. The position step and trajectory tracking performance of the variable stiffness joint are verified through experiments.

Experimental test shows that the joint stiffness can be quickly adjusted. The accuracy of position and trajectory tracking of the joint increases with higher stiffness and decreases with increasing frequency. The fuzzy adaptive controller performed better than the position and stiffness coordination controller in controlling the position step and trajectory tracking of the variable stiffness joint.

A hybrid flux adjustment mechanism is proposed for the components of variable stiffness robot joints, which reduces the mass of the output end of variable stiffness joints and the speed of joint stiffness adjustment. Aiming at the change of system controller performance caused by the change of joint stiffness, a fuzzy adaptive controller is proposed to improve the position step and trajectory tracking characteristics of variable stiffness joints.

This paper aims to present ball bearings with a composite structure based on the bionics principle and shows the comparison between five types of different structures.

By means of the finite element method, the stress and other parameters between different structures are compared and verified. Finally, the comprehensive parameters of different structures are evaluated by the analytic hierarchy process method.

The evaluation of the comprehensive parameters of five types of structures is shown here.

The value of this paper is calculated and compared to the parameters of five types of different structures, and the parameter score evaluation of each structure is given. Different structures can be selected according to different parameter requirements, which to provide a theoretical basis for the design of ball bearings.

The peer review history for this article is available at: https://publons.com/publon10.1108/ILT-10-2019-0413

Nanocomposites represent a new prospective branch in the huge field of polymer materials science and technology. It has been shown that an overall enhancement of properties of polymers can be achieved under certain conditions by the addition of nanoparticles. To examine the influence of microstructure on the tribological performance of nanocomposites, different ways of compounding were used in this study. It was found that the friction and wear behavior of polymeric nanocomposites under sliding environment was rather sensitive to the dispersion states of the nanoparticles. When the microstructural homogeneity of the nanocomposites was improved, their wear resistance could be increased significantly. The present work demonstrates the importance of TiO₂‐nanoparticles dispersion in an epoxy resin matrix, on the materials’ tribological properties, when sliding against a smooth steel counterpart.

Examine the effects of sudden environmental disasters on the advancement of both renewable and conventional energy technologies.

Utilizing panel data from 31 Chinese provinces spanning 2011 to 2022, the SEM (Spatial Error Model) dual fixed model is utilized to examine the impact of sudden environmental disasters on energy technologies.

The findings reveal that: (1) Sudden environmental disasters exert a markedly positive influence on the Innovation of Renewable Energy Technologies (IRET), while their impact on conventional energy technologies is positively non-significant. (2) Sudden environmental disasters not only significantly enhance innovation in local renewable energy technologies but also extend this positive influence to neighboring regions, demonstrating a spatial spillover phenomenon. (3) Research and Development (R&D) funding serves as a partial mediator in the relationship between sudden environmental disasters and renewable ETI. In contrast, Foreign Direct Investment (FDI) exhibits a masking effect.

Consequently, the study advocates for intensified efforts in post-disaster reconstruction following abrupt environmental events, an elevation in the quality of foreign direct investments, and leveraging research funding to catalyze innovation in renewable energy technologies amid unforeseen environmental crises.

The impact on both the environment and operator health is significant. As high-alumina silica glass finds applications in smart devices such as curved mobile phone screens, the grinding of complex curved surfaces necessitates cleaner and more efficient cooling and lubrication methods to enhance processing quality and improve grinding yield rates. This study aims to focus on grinding high-alumina silica glass using micro-lubrication technology and compares its performance with traditional cutting fluid cooling methods.

In the fabrication of mobile phone cover plates composed of high-alumina silicon glass, the incorporation of micro-lubrication grinding technology was undertaken, with the conventional cutting fluid cooling approach serving as the benchmark control group for comparative analysis.

The results indicate that increasing the spray pressure of micro-lubrication within a specific range contributes to reducing grinding surface roughness. At a grinding speed ranging from 25 to 35 m/s, using micro-lubrication can effectively replace the traditional cutting fluid cooling method, resulting in glass surfaces with roughness levels between 0.22 and 0.26. However, at grinding speeds exceeding 35 m/s, the insufficient pressure of the micro-lubricant mist hinders most of the oil mist from entering the grinding zone, leading to inferior cooling performance compared to cutting fluid cooling. Notably, at a grinding speed of 35 m/s, micro-lubrication demonstrates better effectiveness in suppressing chipping during glass grinding compared to traditional cutting fluid cooling methods.

Through the application of micro-lubrication grinding technology, a marked improvement in the grinding quality of high-alumina silicon mobile phone cover plate glass can be achieved, leading to a reduction in surface roughness, a decrease in processing defects and ultimately satisfying the demands for high-precision and high-quality fabrication of such cover plates.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2024-0297