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The purpose of this paper is to track the maximal power of wind energy conversion system (WECS) and enhance the search capability for WECS maximum power point tracking (MPPT).

The hybrid technique is the combination of tunicate swarm algorithm (TSA) and radial basis function neural network.

TSA gets input parameters from the rectifier outputs such as rectifier direct current (DC) voltage, DC current and time. From the input parameters, it enhances the reduced fault power of rectifier and generates training data set based on the MPPT conditions. The training data set is used in radial basis function. During the execution time, it produces the rectifier reference DC side voltage that is converted to control pulses of inverter switches.

Finally, the proposed method is executed in MATLAB/Simulink site, and the performance is compared with different existing methods like particle swarm optimization algorithm and hill climb searching technique. Then the output illustrates the performance of the proposed method and confirms its capability to solve issues.

The purpose of this research is to study how compliance evaluation becomes performed in practice. Compliance evaluation is a common practice among organizations that need to evaluate their posture against a set of criteria (e.g. a standard, legislative framework and “best practices”). The results of these evaluations have significant importance for organizations, especially in the context of information security and continuity. The author argues that how these evaluations become performed is not merely a “social” activity but shaped by the materiality of the evaluation criteria

The authors adopt a sociomaterial practice-based view to study the compliance evaluation through in situ participant observations from compliance evaluation workshops to evaluate organizational compliance against a information security and business continuity criteria. The empirical material was analyzed to construct vignettes that serve to illustrate the practice of compliance evaluation.

The research analysis shows how the information security and business continuity criteria themselves partake in the compliance evaluations by operating through (ventriloqually) the evaluators on three strata: the material, the textual and the structural. The author also provides a conceptualization of a hybrid agency.

This research contributes to lack of studies on the organizational-level compliance. Further, the research is an original contribution to information security and business continuity management by focusing on the practices of compliance evaluation. Further, the research has theoretical novelty by adopting the ventriloqual agency as a hybrid agency to study the sociomateriality of a phenomenon.

This study aims to advance knowledge in international management research about how researchers’ cultural identity in fieldwork encounters may be grounded in the choice of language in multicultural and multilingual projects.

The study is based on critical reflections on the experience of two co-authors as Chinese nationals conducting research in overseas Chinese multinational corporations (MNCs) in developing economies.

Drawing on social identity theory, the authors demonstrate that the cultural identity and cultural insider/outsider positionality of both the researcher and research participants can be shaped by language, translation and other artefacts in cross-cultural interviews, constantly being shifted, managed and renegotiated during qualitative interviewing. This study highlights the politics of language which, when combined with other forms of power relations, such as the researcher’s perceived status, economic development of the MNCs’ home country and the participants’ organisational hierarchy, affect power distribution between the researcher and participants. Researchers often need to move from being an “insider” to an “outsider” and often to an “in-betweener” at different stages in an interview interaction to balance power.

This study contributes to international debates about the complex interplay of languages, politics and identity in multilingual and multicultural qualitative research. In contributing to these literatures, the authors focus on the relatively under-researched Chinese MNCs in other developing countries including Mongolia and Tanzania. Recommendations for researcher training and reflexivity are proposed.

By focusing on the perspective of politicians, this paper aims to question the change brought about by local government financial statements for accountability. It applies the Burns and Scapens’ (2000) framework of accounting change to explore politicians’ routines when using the accrual accounting information and which type of change was induced by financial statements on financial accountability to politicians and citizens.

Considering that accounting reforms take time to unfold their effects, this paper studies two countries that have 11 years of difference in the reform implementation and thus a different accounting maturity. A qualitative research approach was used based on 55 semistructured interviews in five Finnish and six German municipalities with 25 councilors from Finland and 30 from Germany.

Councilors with a longer period of time to adjust to the accounting reforms seem to have developed more routines in using financial statements to assess the financial situation and performance. The change induced in accountability to politicians is partly formal and more evolutionary than revolutionary. The complexity of financial statements can lead to regressive change, especially in financially distressed local governments. As for accountability to citizens, a real change is not observed, reflecting a regressive type of change.

The study contributes to the empirical studies on financial accountability in the public sector context by analyzing the use of financial statements in two-way accountability relations from the perspective of politicians. Thereby, the paper adopts a transnational comparative approach and draws on old institutional economics.

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.

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.

Despite South Africa’s ailing electrical grid, substantial renewable energy (RE) integration is planned for the country. As grid-integrated RE affects all grids differently, this study aims to develop an adaptable grid code-guided renewable power plant (RPP) control real-time simulation testbed, tailored to South African grid code requirements to study grid-integrated RE’s behaviour concerning South Africa’s unique conditions.

The testbed is designed using MATLAB’s Simulink and live script environments, to create an adaptable model where grid, RPP and RPP guiding grid codes are tailorable. This model is integrated with OPAL-RT’s RT-LAB and brought to real-time simulation using OPAL-RT’s OP4510 simulator. Voltage, frequency and short-circuit event case studies are performed through which the testbed’s abilities and performance are assessed.

Case study results show the following. The testbed accurately represents grid code voltage and frequency requirements. RPP point of connection (POC) conditions are consistently recognized and tracked, according to which the testbed then operates simulated RPPs, validating its design. Short-circuit event simulations show the simulated wind farm supports POC conditions relative to short-circuit intensity by curtailing active power in favour of reactive power, in line with local grid code requirements.

To the best of the authors’ knowledge, this is the first design of an adaptable grid code-guided RPP control testbed, tailored to South African grid code requirements in line with which RPP behavioural and grid integration studies can be performed.

Through Bourdieusian sociology, this study aims to interpret a globalized symbolic environment ward by the States and dominated by organizations through the States’ Nobilities enticing and the Euro-American influences disseminated by the cultural circuit of capitalism in the inculcation and incorporation of a class habitus conniving with this logic of domination.

This study has developed a theoretical essay based on the contributions of Bourdieusian sociology to discuss and understand the following concepts and their respective relationships: symbolic environment, globalization, organizations, State, State Nobility, Euro-American influences, cultural circuit of capitalism and class habitus.

The arguments built throughout this theoretical essay recognized how class habitus on environment contributes to organizations establishing themselves as a space that consolidates and replicates the domination logic. As indicated, the State Nobility is an intermediary element between dominant organizations and the State, as dominated.

This theoretical essay signals that less harmful alliances between organizations, the State Nobility and the State could culminate in social, environmental and economic scenarios provided with more inclusion, diversity and preservation.

This study presents an in-depth conceptual analysis to hold power structures responsible as direct and indirect drivers of environmental problems, with their different proportions and severity levels, affecting the planet.

This study proposes an alternative lens to debate and question how much the results presented by the contemporary world order compensate (if in any way) the damage that invades and deteriorate environmental assets.

To prevent the coil from burning or getting damaged, it is necessary to estimate the duration of its operation as long as its temperature does not exceed the permissible limit. This paper aims to investigate the effect of switching on the thermal behavior of impregnated and nonimpregnated windings. Also, the safe operating time for each winding is determined.

The power loss of the winding is expressed as a function of the winding specifications. Using homogenization techniques, the equivalent thermal properties for the homogenized winding are calculated and used in a proposed thermal equivalent circuit for winding modeling and analysis. The validity and accuracy of the proposed model are determined by comparing its analysis results and simulation and measurement results.

The results show that copper windings have better thermal behavior and lower temperature compared to aluminum windings. On the other hand, by impregnating or increasing the packing factor of the winding, the thermal behavior is improved. Also, by choosing the right duty cycle for the winding current source, it is possible to prevent the burning or damage of the winding and increase its lifespan. Comparing the measurement results with the analysis results shows that the proposed equivalent circuit has an error of less than 4% in the calculation of the winding center temperature.

In this paper, the effect of temperature on the electrical resistance of the coil is ignored. Also, rectangular wires were not investigated. Research in these topics are considered as future work.

By calculating the thermal time constant of the winding, its safe operation time can be calculated so that its temperature does not exceed the tolerable value (150 °C). The proposed method analyzes both impregnated and nonimpregnated windings with various schemes. It investigates the effects of switching on their thermal behavior. Additionally, it determines the safe operating time for each type of winding.

Estimation of solar cell parameters, mathematical modeling and the actual performance analysis of photovoltaic (PV) cells at various ecological conditions are very important in the design and analysis of maximum power point trackers and power converters. This study aims to propose the analysis and modeling of a simplified three-diode model based on the manufacturer’s performance data.

A novel technique is presented to evaluate the PV cell constraints and simplify the existing equation using analytical and iterative methods. To examine the current equation, this study focuses on three crucial operational points: open circuit, short circuit and maximum operating points. The number of parameters needed to estimate these built-in models is decreased from nine to five by an effective iteration method, considerably reducing computational requirements.

The proposed model, in contrast to the previous complex nine-parameter three-diode model, simplifies the modeling and analysis process by requiring only five parameters. To ensure the reliability and accuracy of this proposed model, its results were carefully compared with datasheet values under standard test conditions (STC). This model was implemented using MATLAB/Simulink and validated using a polycrystalline solar cell under STC conditions.

The proposed three-diode model clearly outperforms the earlier existing two-diode model in terms of accuracy and performance, especially in lower irradiance settings, according to the results and comparison analysis.