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The purpose of this paper is to study the pipe-type electromagnetic induction heating device under power frequency condition.

To reduce eddy current loss and improve heating efficiency, the structure of a pipe-type power-frequency electromagnetic heating device was optimized. Based on the maximum load flow formula, a parallel excitation winding structure is designed, and the distribution of electromagnetic field under four different powers is analyzed by simulation. Four heating modes were proposed according to the structure of diversion ring, inner wall and outer wall. Two heating modes with better heating effect were obtained by comprehensively considering the factors such as magnetic field distribution, thermal power and energy consumption.

The double-wall structure of the pipe-type electromagnetic heating device can make the heat source distribution more uniform, and the use of power-frequency power supply can increase security, the installation of diversion ring can make the heating more sufficient and the heating efficiency of the two heating methods selected according to the structural performance is more than 90%.

In view of the medium or high frequency of pipe-type electromagnetic heating device, it is necessary to configure high power electronic frequency conversion drive system, and eddy current can only be produced on the tube wall, resulting in uneven distribution of heat sources. A pipe-type power-frequency electromagnetic heating device with double-wall structure was proposed.

Dielectric barrier discharge (DBD) is widely used in the treatment of skin disease, surface modification of material and other fields of electronics. The purpose of this paper is to design a high-performance power supply with a compact structure for excimer lamps in electronics application.

To design a high-performance power supply with a compact structure remains a challenge for excimer lamps in electronics application, a current-source type power supply in a single stage with power factor correction (PFC) is proposed. It consists of an excitation voltage generation unit and a PFC unit. By planning the modes of the excitation voltage generation unit, a bipolar pulse excitation voltage with a high rising and falling rate is generated. And a high power factor (PF) on the AC side is achieved by the interaction of a non-controlled rectifier and two inductors.

The experimental results show that not only a high-frequency and high-voltage bipolar pulse excitation voltage with a high average rising and falling rate (7.51GV/s) is generated, but also a high PF (0.992) and a low total harmonic distortion (5.54%) is obtained. Besides, the soft-switching of all power switches is realized. Compared with the sinusoidal excitation power supply and the current-source power supply, the proposed power supply in this paper can take advantage of the potential of excimer lamps.

A new high-performance power supply with a compact structure for DBD type excimer lamps is proposed. The proposed power supply can work stably in a wide range of frequencies, and the smooth regulation of the discharge power of the excimer lamp can be achieved by changing the switching frequency. The ideal excitation can be generated, and the soft switching can be realized. These features make this power supply a key player in the outstanding performance of the DBD excimer lamps application.

How to successfully drive open innovation (OI) has become an important issue. However, the existing literature on the determinants of OI focuses on organizational and situational factors, while the “human side” of it remains poorly understood. To address such problem, this paper examines the impact of two core qualities of CEOs – CEO power and social capital – on three representative OI modes from a micro-level perspective.

This paper uses the data of 4,213 firm-year observations from Chinese A-share listed companies. A panel logit model is used to test the hypotheses, and the author also uses clustering robust standard errors to ensure the robustness of the model.

A powerful CEO can drive the firm's adoption of technology, organization and market-oriented OI, and different types of social capital have a differential impact on such relationship. Specifically, the CEO's political social capital has a negative moderating effect, while his/her stronger business social capital can enhance the positive relationship between CEO power and various types of OI activities, as well as mitigate the negative effect of political social capital.

This paper echoes the call for more attention to be paid to the microfoundations of OI and provides theoretical implications for research on the convergence of OI and strategic leadership.

The coal-fired power plants have been confronted with new operation challenge since the unified carbon trading market was launched in China. To make the optimal decision for the carbon emissions and power production has already been an important subject for the plants. Most of the previous studies only considered the market prices of electricity and coal to optimize the generation plan. However, with the opening of the carbon trading market, carbon emission has become a restrictive factor for power generation. By introducing the carbon-reduction target in the production decision, this study aims to achieve both the environmental and economic benefits for the coal-fired power plants to positively deal with the operational pressure.

A dynamic optimization approach with both long- and short-term decisions was proposed in this study to control the carbon emissions and power production. First, the operation rules of carbon, electricity and coal markets are analyzed, and a two-step decision-making algorithm for annual and weekly production is presented. Second, a production profit model based on engineering constraints is established, and a greedy heuristics algorithm is applied in the Gurobi solver to obtain the amounts of weekly carbon emission, power generation and coal purchasing. Finally, an example analysis is carried out with five generators of a coal-fired power plant for illustration.

The results show that the joint information of the multiple markets of carbon, electricity and coal determines the real profitability of power production, which can assist the plants to optimize their production and increase the profits. The case analyses demonstrate that the carbon emission is reduced by 2.89% according to the authors’ method, while the annual profit is improved by 1.55%.

As an important power producer and high carbon emitter, coal-fired power plants should actively participate in the carbon market. Rather than trade blindly at the end of the agreement period, they should deeply associate the prices of carbon, electricity and coal together and realize optimal management of carbon emission and production decision efficiently.

This paper offers an effective method for the coal-fired power plant, which is struggling to survive, to manage its carbon emission and power production optimally.

This study aims to offer a hybrid stand-alone system for electric vehicle (EV) charging stations (CS), an emerging power scheme due to the availability of renewable and environment-friendly energy sources. This paper presents the analysis of a photovoltaic (PV) with an adaptive neuro-fuzzy inference system (ANFIS) algorithm, solid oxide fuel cell (SOFC) and a battery storage scheme incorporated for EV CS in a stand-alone mode. In previous studies, either the hydrogen fuel of SOFC or the irradiance is controlled using artificial neural network. These parameters are not controlled simultaneously using an ANFIS-based approach. The ANFIS-based stand-alone hybrid system controlling both the fuel flow of SOFC and the irradiance of PV is discussed in this paper.

The ANFIS algorithm provides an efficient estimation of maximum power (MP) to the nonlinear voltage–current characteristics of a PV, integrated with a direct current–direct current (DC–DC) converter to boost output voltage up to 400 V. The issue of fuel starvation in SOFC due to load transients is also mitigated using an ANFIS-based fuel flow regulator, which robustly provides fuel, i.e. hydrogen per necessity. Furthermore, to ensure uninterrupted power to the CS, PV is integrated with a SOFC array, and a battery storage bank is used as a backup in the current scenario. A power management system efficiently shares power among the aforesaid sources.

A comprehensive simulation test bed for a stand-alone power system (PV cells and SOFC) is developed in MATLAB/Simulink. The adaptability and robustness of the proposed control paradigm are investigated through simulation results in a stand-alone hybrid power system test bed.

The simulation results confirm the effectiveness of the ANFIS algorithm in a stand-alone hybrid power system scheme.

This study aims to investigate the cause of high-order wheel polygonization in a plateau high-speed electric multiple unit (EMU) train.

A series of field tests were conducted to measure the vibration accelerations of the axle box and bogie when the wheels of the EMU train passed through tracks with normal rail roughness after re-profiling. Additionally, the dynamic characteristics of the track, wheelset and bogie were also measured. These measurements provided insights into the mechanisms that lead to wheel polygonization.

The results of the field tests indicate that wheel polygonal wear in the EMU train primarily exhibits 14–16 and 25–27 harmonic orders. The passing frequencies of wheel polygonization were approximately 283–323 Hz and 505–545 Hz, which closely match the dominated frequencies of axle box and bogie vibrations. These findings suggest that the fixed-frequency vibrations originate from the natural modes of the wheelset and bogie, which can be excited by wheel/rail irregularities.

The study provides novel insights into the mechanisms of high-order wheel polygonization in plateau high-speed EMU trains. Futher, the results indicate that operating the EMU train on mixed lines at variable speeds could potentially mitigate high-order polygonal wear, providing practical value for improving the safety, performance and maintenance efficiency of high-speed EMU trains.

Using elements of Bourdieu’s (1986) capitals framework as an underpinning conceptual architecture, this paper theorises the role of symbolic capital in resourcing a specific example of socially entrepreneurial behaviour.

This paper relies on data collected via a qualitative variant of the critical incident technique.

The analysis resulted in three focal themes: power (a dynamic of cooperation rather than domination), age (youth as a means of legitimation) and temporality (as both lever and conduit).

These themes further current understanding of socially entrepreneurial behaviour and potentially catalyse additional questioning and investigation specific to the construct of symbolic capital in this context.

The insights offered in the paper may assist those tasked with supporting success (policymakers and practitioners) in the social entrepreneurship domain.

Relatively little is known about the operationalisation of capitals in the context of social entrepreneurship, and even less about symbolic capital specifically. Particular emphasis is given to moving beyond a focus on the simple mechanics of capital exchange and conversion.

The purpose of this study is to explore how the South African government has used accounting technologies to manage the pervasive issue of racial inequality.

Premised on Foucault’s notion of governmentality, we conducted a qualitative case study. Publicly available archival data are used to determine the extent to which accounting techniques have helped to shape policy responses to racial inequality.

We show that accounting techniques and calculations give visibility to the problems of government and help design a programme to solve racial inequality. The lived experiences and impacts of racism in the workplace have been problematised, turned into statistics, and used to rationalise the need for ongoing government intervention in solving the problem. These processes underpin the development of the scorecard system, which measures the contributions firms have made towards minimising racial inequalities.

This study augments the existing body of Foucauldian literature by illustrating how power dynamics can be counteracted. We show that in governmental processes, accounting can exhibit a dual role, and these roles are not always subordinate to the analysis of political realities. The case of B-BBEE reveals the unintended consequences of utilising accounting to control the conduct of individuals or groups.

This study aims to quantify and prioritize the main causes of lean wastes and to apply reduction methods by employing better waste cause identification methodologies.

We employed fuzzy techniques for order preference by similarity to the ideal solution (FTOPSIS), fuzzy analytical hierarchy process (FAHP), and failure mode effect analysis (FMEA) to determine the causes of defects. To determine the current defect cause identification procedures, time studies, checklists, and process flow charts were employed. The study focuses on the sewing department of a clothing industry in Addis Ababa, Ethiopia.

These techniques outperform conventional techniques and offer a better solution for challenging decision-making situations. Each lean waste’s FMEA criteria, such as severity, occurrence, and detectability, were examined. A pairwise comparison revealed that defect has a larger effect than other lean wastes. Defects were mostly caused by inadequate operator training. To minimize lean waste, prioritizing their causes is crucial.

The research focuses on a case company and the result could not be generalized for the whole industry.

The study used quantitative approaches to quantify and prioritize the causes of lean waste in the garment industry and provides insight for industrialists to focus on the waste causes to improve their quality performance.

The methodology of integrating FMEA with FAHP and FTOPSIS was the new contribution to have a better solution to decision variables by considering the severity, occurrence, and detectability of the causes of wastes. The data collection approach was based on experts’ focus group discussion to rate the main causes of defects which could provide optimal values of defect cause prioritization.

Nanotechnology (NT) advancements in personal protective textiles (PPT) or personal protective equipment (PPE) have alleviated spread and transmission of this highly contagious viral disease, and enabled enhancement of PPE, thereby fortifying antiviral behavior.

Review of a series of state of the art research papers on the subject matter.

This paper expounds on novel nanotechnological advancements in polymeric textile composites, emerging applications and fight against COVID-19 pandemic.

As a panacea to “public droplet prevention,” textiles have proven to be potentially effective as environmental droplet barriers (EDBs).

PPT in form of healthcare materials including surgical face masks (SFMs), gloves, goggles, respirators, gowns, uniforms, scrub-suits and other apparels play critical role in hindering the spreading of COVID-19 and other “oral-respiratory droplet contamination” both within and outside hospitals.

When used as double-layers, textiles display effectiveness as SFMs or surgical-fabrics, which reduces droplet transmission to <10 cm, within circumference of ∼0.3%.

NT advancements in textiles through nanoparticles, and sensor integration within textile materials have enhanced versatile sensory capabilities, robotics, flame retardancy, self-cleaning, electrical conductivity, flexibility and comfort, thereby availing it for health, medical, sporting, advanced engineering, pharmaceuticals, aerospace, military, automobile, food and agricultural applications, and more. Therefore, this paper expounds on recently emerging trends in nanotechnological influence in textiles for engineering and fight against COVID-19 pandemic.