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The aim of this paper is to provide a simple yet accurate and efficient geometric method for thermal homogenization of impregnated and non-impregnated coil winding technologies based on the concept of thermal resistance.

For regular windings, the periodic microscopic cell in the winding space is identified. Also, for irregular windings, the average microscopic cell of the winding is determined. An approximation is used to calculate the thermal resistance of the winding cell. Based on this approximation, the winding insulation is considered as a circular ring around the wire. Mathematical equations are obtained to calculate the equivalent thermal resistance of the cell. The equivalent thermal conductivity of the winding is calculated using equivalent thermal resistance of the cell. Winding thermal homogenization is completed by determining the equivalent thermal properties of the cell.

The thermal pattern of different windings is simulated and compared with the results of different homogenization methods. The results show that the proposed method is applicable for a wide range of windings in terms of winding scheme, packing factor and winding insulation. Also, the results show that the proposed method is more accurate than other winding homogenization methods in calculating the equivalent thermal conductivity of the winding.

In this paper, the change of electrical resistance of the winding with temperature and thermal contact between the sub-components are ignored. Also, liquid insulators, such as oils, and rectangular wires were not investigated. Research in these topics is considered as future work.

Unlike other homogenization methods, the proposed method can be applied to non-impregnated and irregular windings. Also, compared to other homogenization methods, the proposed method has a simpler formulation that makes it easier to program and implement. All of these indicate the efficiency of the proposed method in the thermal analysis of the winding.

This paper aims to introduce an alternative for modeling levitation forces between NdFeB magnets and bulks of high-temperature superconductors (HTS). The presented approach should be evaluated through two different formulations and compared with experimental results.

The T-A and H-Ï• formulations are among the most efficient approaches for modeling superconducting materials. COMSOL Multiphysics was used to apply them to magnetic levitation models and predict the forces involved.The permanent magnet movement is modeled by combining moving meshes and magnetic field identity pairs in both 2D and 3D studies.

It is shown that it is possible to use the homogenization technique for the T-A formulation in 3D models combined with mixed formulation boundaries and moving meshes to simulate the whole device’s geometry.

The case studies are limited to the formulations’ implementation and a brief assessment regarding degrees of freedom. The intent is to make the simulation straightforward rather than establish a benchmark.

The H-ϕ formulation considers the HTS bulk domain as isotropic, whereas the T-A formulation homogenization approach treats it as anisotropic. The originality of the paper lies in contrasting these different modeling approaches while incorporating the external magnetic field movement by means of the Lagrangian–Eulerian method.

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.

Intumescent coatings are nowadays a dominant passive system used to protect structural materials in case of fire. Due to their reactive swelling behaviour, intumescent coatings are particularly complex materials to be modelled and predicted, which can be extremely useful especially for performance-based fire safety designs. In addition, many parameters influence their performance, and this challenges the definition and quantification of their material properties. Several approaches and models of various complexities are proposed in the literature, and they are reviewed and analysed in a critical literature review.

Analytical, finite-difference and finite-element methods for modelling intumescent coatings are compared, followed by the definition and quantification of the main physical, thermal, and optical properties of intumescent coatings: swelled thickness, thermal conductivity and resistance, density, specific heat capacity, and emissivity/absorptivity.

The study highlights the scarce consideration of key influencing factors on the material properties, and the tendency to simplify the problem into effective thermo-physical properties, such as effective thermal conductivity. As a conclusion, the literature review underlines the lack of homogenisation of modelling approaches and material properties, as well as the need for a universal modelling method that can generally simulate the performance of intumescent coatings, combine the large amount of published experimental data, and reliably produce fire-safe performance-based designs.

Due to their limited applicability, high complexity and little comparability, the presented literature review does not focus on analysing and comparing different multi-component models, constituted of many model-specific input parameters. On the contrary, the presented literature review compares various approaches, models and thermo-physical properties which primarily focusses on solving the heat transfer problem through swelling intumescent systems.

The presented literature review analyses and discusses the various modelling approaches to describe and predict the behaviour of swelling intumescent coatings as fire protection for structural materials. Due to the vast variety of available commercial products and potential testing conditions, these data are rarely compared and combined to achieve an overall understanding on the response of intumescent coatings as fire protection measure. The study highlights the lack of information and homogenisation of various modelling approaches, and it underlines the research needs about several aspects related to the intumescent coating behaviour modelling, also providing some useful suggestions for future studies.

Weak repeatability is observed in handcrafted keypoints, leading to tracking failures in visual simultaneous localization and mapping (SLAM) systems under challenging scenarios such as illumination change, rapid rotation and large angle of view variation. In contrast, learning-based keypoints exhibit higher repetition but entail considerable computational costs. This paper proposes an innovative algorithm for keypoint extraction, aiming to strike an equilibrium between precision and efficiency. This paper aims to attain accurate, robust and versatile visual localization in scenes of formidable complexity.

SiLK-SLAM initially refines the cutting-edge learning-based extractor, SiLK, and introduces an innovative postprocessing algorithm for keypoint homogenization and operational efficiency. Furthermore, SiLK-SLAM devises a reliable relocalization strategy called PCPnP, leveraging progressive and consistent sampling, thereby bolstering its robustness.

Empirical evaluations conducted on TUM, KITTI and EuRoC data sets substantiate SiLK-SLAM’s superior localization accuracy compared to ORB-SLAM3 and other methods. Compared to ORB-SLAM3, SiLK-SLAM demonstrates an enhancement in localization accuracy even by 70.99%, 87.20% and 85.27% across the three data sets. The relocalization experiments demonstrate SiLK-SLAM’s capability in producing precise and repeatable keypoints, showcasing its robustness in challenging environments.

The SiLK-SLAM achieves exceedingly elevated localization accuracy and resilience in formidable scenarios, holding paramount importance in enhancing the autonomy of robots navigating intricate environments. Code is available at https://github.com/Pepper-FlavoredChewingGum/SiLK-SLAM.

The purpose of this study is to examine both the responses of auditees to corporate governance audit (CGA) regulation and the practices of CGA auditors.

The study used a mixed method. Content analysis of 200 annual and CGA reports was carried out for 13 years, from 2008 to 2021, split into voluntary disclosure and mandatory disclosure periods. Quantitative analysis was also conducted using Kruskal–Wallis and Dunn's tests. Data gathered were interpreted through the lens of isomorphism and Oliver's (1991) strategic responses to institutional processes.

The study revealed that in the voluntary disclosure period, auditees responded mainly with acquiescence, motivated by mimetic isomorphic pressure. In the mandatory disclosure period, auditee responses ranged from acquiescence to dismissal of corporate governance regulation (i.e. coercive isomorphic pressure). Auditor reporting of CGA findings was found to be heterogeneous, suggesting that normative and mimetic isomorphism did not homogenize auditor practices.

The absence of uniform auditee responses to CGA regulation during the mandatory disclosure period suggests that the purpose of mandating the regulation has not yet been achieved and may signal inadequate coercive isomorphic pressure from the Financial Reporting Council of Nigeria (FRCN). Similarly, heterogeneous reporting of CGA findings by corporate governance auditors inhibits the comparability of audit findings, limiting their value for information users.

This study examines corporate governance auditor practices and auditee responses to corporate governance audit regulation.

This study aims to investigate the nature of management accounting (MA) change and the institutional pressures driving the change using the context of an emerging economy – Bangladesh.

The study collected data from 20 listed companies in Bangladesh through in-depth interviews. It uses the typology of MA change proposed by Sulaiman and Mitchell (2005) in identifying the nature and extent of MA change executed during the preceding three years. A modified version of Granlund and Lukka’s (1998) model is used to identify and explain the impact of institutional and economic pressures on MA change.

This study finds that MA changes have taken place in the Bangladeshi listed companies in the forms of modification, addition and replacement during the preceding three years. The findings also showed that mimetic and coercive pressures influence the adoption of new MA techniques or changes in the existing MAP. The impact of economic forces (specifically the advancement of operating technology and competition intensity) on MA change is also well evident.

This study focuses on the typology of MA change and the institutional forces affecting the MA change, which have rarely been addressed in the context of an emerging and developing economy.

Business models (BMs) are becoming increasingly crucial for value creation in the healthcare sector. The study explores the conceptualization and application of BM concepts within the healthcare sector and investigates their evolution in emerging economies (EEs) and developed economies (DEs). This study aims to uncover these two contexts' shared characteristics and unique variances through a comparative analysis.

The paper systematically investigates and consolidates the literature on healthcare by employing the antecedents, decisions and outcomes (ADO) framework and finally examines 71 shortlisted articles published between 2003 and 2022.

The recognition of the BM within healthcare is increasing, both in EEs and DEs. EEs prioritize value creation and capture through cost efficiency, while DEs focus on innovation. Key theories employed include a resource-based view, the network theory and the theory of innovation. Case studies are commonly used as a methodology. Further research is needed to explore the decisions and outcomes of BMs.

The study adopts stringent filtration and keyword criteria, potentially excluding relevant research. Future researchers are encouraged to broaden their selection criteria to encompass a more extensive range of relevant studies.

Beyond comparing and highlighting gaps in BMs between EEs and DEs, benchmarking DE's healthcare business models (HBMs) helps healthcare organizations in EEs align their practices, mitigate risks and establish efficient healthcare systems tailored to their specific contexts. The study adopts stringent filtration and keyword criteria, potentially excluding relevant research. Future researchers are encouraged to broaden their selection criteria to encompass a more extensive range of relevant studies.

The study analyzes HBMs using an SLR framework perspective and provides practical implications for academicians and practitioners to enhance their decision-making.

This article provides an overview and analysis of 50 years of European policies, actions, and challenges to align its higher education and research, as well as lessons learned from this for similar initiatives elsewhere.

The study builds on a comprehensive overview and study of policy documents and scholarly literature to identify by decade the main policies and actions and the related challenges towards a European Higher Education and Research Area.

The findings make clear the key rationales, challenges, shifts and lessons to be learned from 50-year European policies for the alignment of higher education.

Its value lies in the historical overview and analysis of current initiatives, in particular the European Universities Initiative (EUI), to provide a historical and geographical context, which might give insight for similar initiatives elsewhere.

A significant number of studies suggest that both international cooperation (IC) and English proficiency (EP) greatly assist internationalization of higher education (IHE). Yet, more evidence is required to confirm their relationship. Hence, this paper intends to investigate whether any association prevails between IC and EP, and if so, how both domains facilitate IHE.

This study employed a qualitative approach to examine how IC and EP potentially influence each other, as well as the way they shape IHE.

The main key finding reported in this study is that IC plays a significant role in internationalization efforts, with English serving as a critical medium.

The findings suggest that although IC can positively influence EP and the overall level of IHE, the newly built undergraduate institutions (NBUIs) in China should be careful not to fall into the dual traps of number-crunching and income-generation instruments. NBUIs in China may consider changing their IC strategies and seek to join some authoritative or high-reputation networks in other developing countries to expand their horizons.

This study contributes to the literature on IHE by exploring the connections between IC and EP and how they affect IHE, thus providing insights into advancing institutional internationalization. It is achieved through expanding institutions' IC or joining international networks while overcoming linguistic barriers.