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The purpose of this paper is to study the insulation structure optimization method of multiwinding high-frequency transformer (HFT).

This paper takes 100 kW, 10 kHz multiwinding HFT as the research object. First, the distribution of electric field strength within the core window of multiwinding HFT with different winding configurations is simulated by the electrostatic field finite element method. The symmetrical hybrid winding structure with minimum electric field strength is selected as the insulation design. To reduce the electric field strength at the end region of the winding, the electrostatic ring and angle ring are designed based on the response surface method.

The optimal results show that the maximum electric field strength can be reduced by 15.4%, and the low voltage stress can be achieved.

The above research provides guidance and basis for the optimal design of insulation structure of multiwinding HFT.

The purpose of this paper is to study the multi-objective optimization design method of high-power high-frequency magnetic-resonance air-core transformer (ACT).

First, this paper studies the interleaved winding technology, the process of modeling and simulation, the calculation method of high-frequency loss of Litz wire and the design of magnetic shielding in detail. Second, the multi-objective optimization design process of high-frequency magnetic-resonance ACT is established by parametric scanning method and orthogonal experiment method.

An ACT model of 2 kV/100 kW/81.34 kHz was designed. The efficiency, weight power density and volume power density are 99.61%, 21.6 kW/kg and 5.1 kW/kg, respectively. Finally, the multi-physical field coupling simulation method is used to calculate the port excitation voltages and currents and temperature field of ACT. The maximum temperature of the ACT is 95.5 °C, which meets the design requirements.

The above research provides guidance and basis for the optimization design of high-power high-frequency magnetic-resonance ACT.

Because the nanocrystalline core is widely used in power electronic equipment, and the excitation waveform of its working mode is complex, the vibration at medium and high frequencies cannot be ignored. Therefore, this study aims to study the vibration mechanism of nanocrystalline strip and the vibration characteristics of nanocrystalline magnetic ring under different excitation waveforms.

First, the electromagnetic vibration mechanism between nanocrystalline strips is analyzed by finite element analysis, and the force of the magnetic ring with and without air gap is compared and analyzed. Then, the vibration of nanocrystalline magnetic ring under different excitation waveforms such as sine wave, triangular wave, symmetric rectangular wave and asymmetric rectangular wave is analyzed by experimental method. The acceleration time domain waveform measured by the experiment is analyzed by fast Fourier transform, and the vibration is analyzed according to the spectrum.

Because of the increase of magnetic flux leakage, the volume force density and the Maxwell force on the surface of the nanocrystalline magnetic ring will increase after the air gap is opened, resulting in the intensification of vibration. Under symmetric/asymmetric rectangular wave excitation, the vibration acceleration varies with the duty cycle. Due to the influence of harmonic excitation, the relationship between the main frequency of vibration and the excitation frequency is not two times, and its multiple decreases with the increase of excitation frequency.

The research and analysis of this paper can promote the application of new magnetic materials in electrical equipment in small and medium-sized and medium- to high-frequency fields.

This chapter describes the journey of four social entrepreneurs in the Malaysian landscape. The objectives of the case study are to provide a description of the social entrepreneurship development in Malaysia and to illustrate how social entrepreneurs start their ventures, and mobilise change within this landscape. Primary data was collected through a survey and indepth interviews. Four social entrepreneurs participated in this study. The findings show that the Malaysian social entrepreneurship landscape is thriving and supportive, giving many opportunities for individuals to establish social enterprises. The indepth interviews revealed that the social entrepreneurs were motivated to start their social enterprises after being exposed to various socio-economic problems of diverse communities. They leveraged on their strength, both technical and business to create social enterprises. Digitalisation is a major enabler for the social enterprises where ICT tools are used to create solutions to optimise socio-economic impact. Training, coaching and mentoring are also widely used to empower the target beneficiaries. All the social entrepreneurs are deeply aware of the sustainable developmental goals (SDGs) and have strategically incorporated the relevant SDGs into their business model to guide impact measurement. This case study contributes to the field by providing insights on the what drives the ‘selfless side’ of an individual to start a social enterprise, and how do social enterprises leverage on available resources to grow and sustain their ventures. It also provides insights on how to pilot and scale social enterprises.

This research deals with the critical factors of quality and their significance to perceived security as an effort to build a formidable loyalty of customers in a technology driven service environment. The primary purpose of this study is to investigate the key contributing elements of functional and service quality on perceived security and to further analyze its impact on customer satisfaction and loyalty.

A hypothesized structure model is proposed and justified using the data collected in the manufacturing and telecommunication service sectors in South Korea through survey with total 647 respondents. To clarify the reliability of model and validity of the proposed hypothesis, AMOS 24.0 software was utilized. Furthermore, two moderating variables were adopted for the depth understanding.

This study reveals that service quality dominantly influences the level of perceived security due to its characteristics that are mostly formed on the stage of customer-contact activity. This study further provides a strategic methodology for manufacturing and telecommunication firms to foster sustainable growth by focusing on perceived security during the service delivery process.

This finding is particularly important as Ontact technology becomes increasingly critical during the COVID-19 pandemic. It is worthwhile noting that the research outcome of this study may, in turn, trigger the trust issue that need to be combined with quality in the era of Industry 4.0.

This paper aims to investigate cross-gender effects of gender stereotypes in advertising. More specifically, it proposes that the negative effects found in studies of women’s reactions to stereotyped female portrayals should hold across gender portrayal and target audience gender.

In two experimental studies, the effects of stereotyped portrayals (vs non-stereotyped portrayals) across gender are compared.

The results show that advertising portrayals of women and men have a presumed negative influence on others, leading to higher levels of ad reactance, which has a negative impact on brand-related effects across model and participant gender, and for gender stereotypes in terms of physical characteristics and roles.

Whereas previous studies have focused on reactions of women to female stereotypes, the current paper suggests that women and men alike react negatively to stereotyped portrayals of other genders.

The results indicate that marketers can benefit from adapting a more mindful approach to the portrayals of gender used in advertising.

The addition of a cross-gender perspective to the literature on gender stereotypes in advertising is a key contribution to this literature.

The purpose of this paper is to provide a more expansive recounting of the process of fieldwork, taking place over a number of years in diverse locations, in order to show how research design develops through the process of field research, as well as to highlight the complexity of fieldwork, especially issues of access, identity, and power.

The paper is based on the author's fieldwork experiences in Sierra Leone, working from and expanding upon fieldnotes from time in the field. Reflexive, autoethnographic personal narratives of fieldwork experiences are juxtaposed with theoretical writing about ethnographic observation and qualitative research.

The expansive discussion of the process of fieldwork and the development of the research project through time demonstrates and explicates the complexity and temporal dimensions of qualitative field research. Issues of access, identities, and power/privilege are also crucial aspects of the fieldwork process.

This paper shows the importance of acknowledging and articulating the development of fieldwork and research design over time and in different places. It also discusses the complexity of fieldwork due to issues of access, identity, and power. Its claims are limited by its focus on one case, the author's fieldwork.

This piece will help members of society better understand the process of qualitative fieldwork. Given its format and writing style, this piece can be easily read and understood by interested members of the public.

This paper provides narratives and commentary that provide a more complete picture of the practice of field research and the development of research design over the course of time and in diverse locations. This will be valuable to researchers, especially those preparing for field experiences for the first time or for their first time in a particular field, as well as students interested in learning about qualitative fieldwork practices.

Examines the fifthteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Examines the thirteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.