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The purpose of this paper is to study conducted electromagnetic interference (EMI) of the high-low voltage DC/DC converter based on GaN high-electron-mobility transistors (HEMTs) in electric vehicle, and design EMI filters to suppress the conducted EMI.

The conducted EMI propagation model is established through simulation and analysis studying the influences of parasitic parameters, operation mode, output power and near-field capacitive coupling effects on conducted EMI of the DC/DC converter and comparing the suppression effects of EMI filters with different topologies to select the best EMI filter.

It is shown that parasitic parameters, operation mode, output power and near-field capacitive coupling effects can affect the conducted EMI of the DC/DC converter, and EMI filters of the CLC topology can effectively suppress the conducted EMI below the limit of CISPR 25.

Analysis of conducted EMI and design of EMI filters greatly facilitate further explorations and studies on EMI problems of the high-low voltage DC/DC converter based on GaN HEMTs.

In response to internationalization and globalization, especially in higher education, universities in non-English-speaking countries have implemented English as a medium of instruction (EMI). The purpose of this study is to assess the satisfaction of students in terms of dimensions of EMI courses and examine the relationship between student motivation, engagement, and satisfaction with EMI courses.

By using a quantitative approach based on structured questionnaires of 437 Vietnamese undergraduate students, this study applied hierarchical regression analysis to examine the relationship between student motivation, engagement, and satisfaction with EMI courses.

Students have a relatively positive perception of the EMI courses that they have taken. In particular, they were most satisfied with teachers' teaching characteristics and least satisfied with students' learning characteristics. The study also confirmed that cognitive and emotional engagement have mediating effects on the relationship between motivation and students' satisfaction with EMI courses.

This study suggests that both educational institutions and teachers in non-speaking English countries should pay more attention to motivational factors to engage students in learning and ensure that they are satisfied with EMI courses.

The paper seeks to provide a commentary on Michailova and Jormanainen's viewpoint entitled “Knowledge transfer between Russian and Western firms: whose absorptive capacity is in question?”(CPoIB, Vol. 7 No. 3).

The paper offers a critical analysis of issues regarding knowledge transfer and absorptive capacity in the context of business interactions between Russian and Western firms.

Based on the author's 25 years of experience in knowledge transfer between Western and Russian counterparts (managers, companies and researchers), the generic concepts “knowledge”, “Western” and “Russian” no longer provide meaningful points of reference for actual knowledge transfer.

Research so far has failed to develop the tools for realistic assessment of current Russian and Western absorptive capacity and has provided inadequate explanations for the hurdles, resistances and other barriers still entailed in the process of knowledge transfer between the two sides. This commentary suggests that the basic assumptions behind the scholarly literature about knowledge transfer between Western and Russian interactants should be examined carefully and that research should focus on identifying the factors that facilitate as well as the factors that impede effective knowledge transfer. The scholarly conversation on the topic needs to continue, particularly through genuine collaboration between Russians and Westerners and between researchers and practitioners.

It is recommended that a system is needed for establishing and sustaining effective knowledge transfer which would both enrich understanding of how such transfer actually works and articulate specific behavorial guidelines that will help each side to transfer their relevant knowledge and increase their own absorptive capacity more effectively.

The commentary challenges some existing views and practices and outlines new directions in relation to both research and practice regarding knowledge transfer between Russian and Western firms.

The frequency simulation and optimisation of electromagnetic compatibility (EMC) filter is often computation time consuming. The purpose of this paper is to propose an approach for easy and fast modelling and optimization of power electronics structures.

The paper proposes an approach for easy and fast modelling and optimization of power electronics structures. It focuses on the EMC filter design. To achieve this task time simulation, FFT and automatic frequency modelling are combined.

An automatic frequency modelling is proposed and also gives automatically the model gradients. Therefore, the model can be used to optimize the EMC filter, but also can help in choosing its topology. Several optimization algorithms are used and compared.

The power electronics load is supposed to be a set of predefined harmonic sources, obtained by time simulation + FFT before the optimisation process.

The frequency model allows for the rapid designing and comparing of several structures or modelling hypothesis with regard to the parasitic elements and circuit imperfections.

The frequency model is automatically generated, and sizing criteria on the component (e.g. inductors, capacitor) can be added in an analytical form, for example, to deal with volume or mass criteria.

As a result of the ongoing globalization and commercialization of higher education, English is increasingly being used as the language of instruction in universities across the globe. Despite the growing popularity of English-medium instruction (EMI) for academic subject instruction in Kazakhstan, there is limited research on regional university undergraduate students' attitudes towards learning EMI. This article explores a case study of a chemistry undergraduate program in Kazakhstan, where EMI is used. This study seeks to identify beliefs related to EMI, student attitudes and the challenges faced when studying science in English.

Qualitative data were collected using open-ended questionnaires and semi-structured interviews with individuals selected using purposive sampling, which were then triangulated using classroom observations. The study employed a thematic analysis methodology to examine the gathered data, which included transcripts from interviews, audio logs from classroom observations and survey responses.

Following an in-depth look at the main themes, there were a variety of codes that made more sense when arranged in one of the four primary groups. These categories primarily focused on the possible obstacles that may be encountered when adopting EMI in Kazakhstan's higher education institutions. They are as follows: linguistic, managerial, cultural and emotional.

The results of this study will contribute to the development of improved EMI policies and practices that are more comprehensive, equitable and efficient.

Shipping courses contain much technical and specialist knowledge and present particular challenges for English medium instruction (EMI). This paper aims to investigate both student perceptions of the importance and satisfaction level of EMI in shipping courses in higher education in Taiwan and the perceptions of expert stakeholders through qualitative interviews.

Importance-performance analysis (IPA) is used to gather data on participants’ perceptions of what is (un)important and (un)satisfactory. Based on past studies, four dimensions with 20 items were developed and 121 effective questionnaires were collected. Further, qualitative interviews with expert stakeholders (n = 9) are undertaken to gather data to contextualize and complement the quantitative student data.

Findings show students attributed high importance but low satisfaction to items such as course learning objectives and students’ English level, and low importance and high satisfaction to items such as electronic teaching platform and relevance of subject to practice. Factor analysis and cluster analysis were used to divide samples into three groups. Qualitative interview results confirm many of the quantitative findings but also show where some quantitative findings require more attention or investment when delivering EMI programmes.

Questionnaire samples focus on university students. Other related field samples (e.g. EMI teachers, shipping teachers, English teachers, etc.) could be surveyed and compared in future studies. Qualitative interviews could also be expanded to other stakeholders such as government policymakers.

The findings of IPA in the shipping courses and the qualitative interviews can be used for both teaching design and implementation in related courses by university lecturers and other stakeholders (e.g. policy and decision-makers). Such approaches can enhance students’ learning motivation and teaching performance.

This paper provides important guidance and diagnosis for how to introduce English teaching in shipping courses. Related courses can be further applied in higher education to popularize and promote EMI teaching in shipping and related fields.

EMI has seldom been studied in the context of shipping courses in the past. This paper adopts IPA method and qualitative interviews to complement previous studies and address gaps in recent research. It is expected that the research findings could be adapted and applied in other fields.

Present 3D electromagnetic simulators have high accuracy, but they are time and memory expensive. Because of that, fast and simple expression for impedance is also necessary for initial inductor design. In this paper new efficient method for total impedance calculation of ferrite electromagnetic interference (EMI) suppressor is given. By using an algorithm, it is possible to predict correctly all variations of electrical characteristics introduced by varying geometry parameters of EMI suppressor.

The starting point for calculation of electrical characteristics of EMI suppressor is Greenhouse theory. Greenhouse decomposed inductor into its constituent segments. Basically, all segments of conductive layer are divided into parallel filaments having small, rectangular cross sections. The self‐ and mutual‐inductance were calculated using the concept of partial inductance. Total impedance of EMI suppressor is calculated taking care of dimension of chip size, material that are used and geometry of conductive layer.

The Simulator for Planar Inductive Structures (SPIS™) simulates effects of ferrite materials and geometrical parameters of planar inductive structures. With proposed software tool, designers can predict performance parameters quickly and easily before costly prototypes are built. SPIS™ software offers substantially reduced time to market, and increases device performance. The computed impedances, given by our software tool are compared with measured data and very good agreement was found.

Applied flexible efficient methods for impedance calculation of EMI suppressor are able to significantly increase the speed design of multilayer suppressors for universal series bus, low‐voltage differential signaling and in other high‐speed digital interfaces incorporated in notebooks and personal computers, digital cameras and scanners. Also, ferrite suppressors have been successfully employed for attenuating EMI in switching power supplies, electronic ignition systems, garage door openers, etc.

The paper presents realized structures of ferrite EMI suppressors. New geometries of conductive layer are proposed. In addition, using simple model of inductor, the paper develops a CAD simulation tool SPIS™ for calculation of electrical characteristics of EMI suppressors with different geometry of conductive layer.

The purpose of this paper is to provide a theoretical platform for studying the characteristic of random carrier frequency (RCF) modulation and analyze the related parameters in terms of electromagnetic interference (EMI) suppressing.

In this paper, the expression of the amplitude of switching voltage power spectra under the RCF mode is presented. According to the expression, the effectiveness of related parameters on EMI mitigation is discussed. Theoretical predictions are confirmed with a closed‐loop boost converter which power is 7.5 W and nominal switching frequency is 200 KHz. Finally, special attention has been paid to output voltage ripple.

Under RCF scheme, with increasing of random degree, the spectrum of switching voltage is dispersed, so the power spectrum density amplitude of switching voltage falls, and then the level of EMI is lowered. This theory shows that the voltage power spectrum density attains maximum when d=0.5, so in the spread spectrum modulation, the duty cycle of 0.5 should be avoided in terms of conducted EMI mitigation.

The analytical expression of switching voltage power spectra under the RCF mode is presented, providing a theoretical platform for the related research. The selection of duty cycle has effect on EMI level is put forward for the first time. Voltage ripple is discussed in close‐loop circuit.

The purpose of this paper is to develop a novel technique for the pre-design of a printed circuit board (PCB) of a DC-DC power converters where the placement of electric components can cancel the electromagnetic emissions through subtractive coupling and in this sense to minimize the stray magnetic and electric fields at a specific location. For this work the location of interest is a current transducer used for control purposes positioned in the center of a DC-DC Cuk converter board as a constrain.

The methodology of design is based on the development of an interface software platform through MatLab script coding which interconnects the solution of a numerical analysis software and an optimization technique. The numerical analysis software is based on finite element calculations where quasi-static field analysis are performed to calculate the radiated electric and magnetic fields. The optimization technique is conducted by genetic algorithms (GAs).

The results for the proposed procedure for PCB design show a significant reduction in radiated electromagnetic (EM) field at the susceptible device in the PCB. Even when the optimization procedure is applied only for the sensor center, the field reduction is extended for a wide region around the sensor. The proposed technique not only reduces the fundamental field component but also all the harmonic contents for the electromagnetic field. It is demonstrated that it is possible to cancel the emissions by means of varying the location and orientation of the passive elements avoiding the utilization of electromagnetic interference filters and complex modulations.

The novelty of the design procedure falls in the fitness function programming where an interface software platform is built through MatLab scripting to connect a 3D-FE analysis and the GA. The finite element analysis address the radiated EM calculation while the GA focus in the minimization of it. This computational platform has the flexibility to be easily adapted for the PCB design of any power electronic converter where the radiated EM compliance is required as well as extended to perform emissions minimization outside or/and inside the PCB.

The purpose of this paper is to deal with the design of passive filter for power electronics voltage inverters used in aircraft electrical drives (a permanent magnet synchronous machine fed by a six-phase voltage inverter with PMW control), using optimization for both sizing and sensibility analyses.

The approach is generic. An aid allows to modify easily the frequency model and so to check various study cases, and to carry out the filter optimization for different topologies or control strategies.

The approach is generic. An aid allows to modify easily the frequency model and so to check various study cases, and to carry out the filter optimization for different topologies or control strategies.

The power electronics load is supposed to be a set of predefined harmonic sources, obtained by experiment or time simulation plus fast fourier transformation before the optimization process.

The problem has numerous constraints on the components, mainly technological constraints. The volume is minimized, respecting electromagnetic standards and an electro magnetic interference filter prototype has been made.

The frequency model is automatically generated. A complex aircraft application has been studied thanks to the approach. Several sensibility analyses have been carried out. An EMC filter has been sized and an experimental prototype has been made, comforting the sizing by optimization.