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This paper aims to achieve an optimal design for distribution transformers considering cost and power losses. Particle swarm optimization (PSO) algorithm is used as an optimization tool for minimizing the objective functions of design procedure which are cost and electrical and iron losses.

In this paper, distribution transformer losses are considered as operating costs. Also, transformer construction cost which depends on the amount of iron and copper in the structure is assumed as its initial cost. In addition, some other important constraints such as appropriate ranges of transformer efficiency, voltage regulation, temperature rise, no-load current, and winding fill factor are investigated in the design procedure. The PSO algorithm is applied to find optimum amount of needed copper and iron for a typical distribution transformer. Moreover, transformer impedance considered as a constraint to achieve an acceptable voltage regulation in the design process.

It is shown that the proposed design procedure provides a simple and effective approach to estimate the flux and current densities for minimizing the active part cost and active power losses which means reduction in amount of transformer total owning cost (TOC).

The methodology advances a proposal for reducing distribution transformers costs using PSO algorithm. The approach considers the aforementioned constraints and TOC to minimize the active part cost and maximize the efficiency. It is demonstrated that a designed transformer will not be optimum when the transformer losses over years are not considered in design procedure. Finally, the results prove the effectiveness of the proposed procedure in designing cost-effective distribution transformers from its initial cost until its whole life.

The purpose of this paper is to give a comprehensive description of various safety factors that need to be determined while assessing the short‐circuit strength of transformers.

Factors of safety are divided into two categories: radial and axial. Some of the latest approaches in assessing the strength are elaborated.

Six major sets of calculations are identified: three each for radial and axial electromagnetic forces. Corresponding factors of safety are defined and calculated for practical transformers. These factors are related to the strength and stability aspects of windings.

The work gives pointers for further research at appropriate places while highlighting the challenges involved in the assessment of the short‐circuit strength.

The presented overview of the factors of safety can be a useful guide for the practicing transformer engineers.

The main contribution of the reported work is in highlighting the intricacies associated with the subject of short‐circuit strength of power transformers. It can serve as a reference document for future research works in the area since the procedures are outlined for calculating the factors of safety through six case studies.

Previous research suggests that women receive less critical attention and acclaim in popular music. The authors expect that gender differences in the amount and content of media discourse about popular musicians occur because music critics draw on the cultural frame of gender as a primary tool for critical evaluation. In order to explore the role of gender as a frame through which aesthetic content is evaluated, the authors conduct detailed content analyses of 53 critical reviews of two versions of the popular album 1989 – the original released by Taylor Swift in 2014 and a cover version released by Ryan Adams less than a year later. Despite Swift’s greater popularity and prominence, the authors find that reviews of her version of the album are more likely to focus on her gender and sexuality; less likely to describe her as emotionally authentic; and more likely to use popular aesthetic criteria in evaluating her music. By contrast, Ryan Adams was more likely to be seen by critics as emotionally authentic and to be described using high art aesthetic criteria and intellectualizing discourse. The authors address the implications of the findings for persistent gender gaps in many artistic fields.

This paper aims to give a perspective about the variety of techniques which are available and are being further developed in the area of coupled field formulations, with selective bibliography and practical examples, to help postgraduate students, researchers and designers working in design or analysis of electrical machinery.

This paper reviews the recent trends in coupled field formulations. The use of these formulations for designing and non‐destructive testing of electrical machinery is described, followed by their classifications, solutions and applications. Their advantages and shortcomings are discussed.

The paper gives an overview of research, development and applications of coupled field formulations for electrical machinery based on more than 160 references. All landmark papers are classified. Practical engineering case studies are given which illustrate wide applicability of coupled field formulations.

Problems which continue to pose challenges to researchers are enumerated and the advantages of using the coupled‐field formulation are pointed out.

This paper gives a detailed description of the application of the coupled field formulation method to the analysis of problems that are present in different electrical machines. Examples of analysis of generators and transformers with this formulation are presented. The application examples give guidelines for its use in other analyses.

The coupled‐field formulation is used in the analysis of rotational machines and transformers where reference data are available and comparisons with other methods are performed and the advantages are justified. This paper serves as a guide for the ongoing research on coupled problems in electrical machinery.

This study aims to investigate the combined use of System Dynamics (SD) applications in Enterprise Engineering (EE) research and practice. SD application in EE is becoming widely accepted as a tool to support decision-making processes and for capturing relationships within enterprises.

A systematic literature review (SLR) is conducted using a standard SLR method to provide a comprehensive review of existing literature. The search was conducted on ten platforms identifying 30 publications which were analysed through the use and development of a codebook.

The SLR showed that 90% of the result set consisted of peer-reviewed academic conferences and journal papers. The SLR identified a highly dispersed author set of 83 authors. Amongst these authors, Vinay Kulkarni was an active author who has co-authored up to four publications in this research area. The analysis further revealed that the combined use of SD applications and EE is an emerging research area that still needs to develop in maturity. While all phases of EE have received attention, the current research work is more focused on the design phase. The important gap between model development and implementation is identified.

The study elucidates the existing status of interdisciplinary research combining techniques from the SD and EE disciplines, suggesting future research topics that combine the strengths of these existing disciplines.

The purpose of this paper is to apply a 3D methodology to assess the heating hazard on transformer covers and present a practical tool to design amagnetic inserts arrangement.

A practical 3D methodology linking an electromagnetic analytical formulation with thermal finite element method is used for computation. Such methodology allows the evaluation of the temperature on metallic device elements heated by electromagnetic induction. This is a 3D problem which in the case of power transformers becomes especially difficult to apply due to the discretization requirement into the thin skin depth penetration compared to big machine dimensions.

From the numerical solution of the temperature field, decisions on dimensions and different amagnetic inserts arrangements can be taken to avoid hot spots on transformer covers.

Some parameters presented in the model as heat exchange coefficients and material properties are difficult to determine from formulae or from the literature. The accuracy of the results strongly depends on the proper identification of those parameters, which the authors adjust based on measurements.

Differing from previous works found in the literature, which focus their results in power loss computation methods, this paper evaluates losses in terms of temperature distribution, which is easier to measure and validate over transformer covers. Moreover, an experimental work is presented where the temperature distribution is measured over a steel cover plate and a cover plate with amagnetic insert.

This chapter elucidates the wage differential between male and female informal workers in urban labour market by using employment and unemployment survey 61st (2004–2005) round, 68th (2011–2012), and Periodic Labour Force Survey 2019–2020 data of National Sample Survey Office (NSSO) unit level data. This study found that gender inequality not only increased during getting job but also persists after getting job during wage distribution. Based on the Oaxaca–Blinder (OB) decomposition, it is revealed that gender wage inequality is more in the labour market due to the labour market discrimination, that is, unexplained components. Hence, this study helps researcher, policy makers and government to fix the gender wage discrimination issues exist in the Indian labour market. This will enhance economic growth through the rise of the women labour force participation.

The simplified modeling of many physical processes results in a second-order ordinary differential equation (ODE) system. Often the damping of these resonating systems cannot be defined in the same simplified way as the other parameters due to the complexity of the physical effects. The purpose of this paper is to develop a mathematically stable approach for damping resonances in nonlinear ODE systems.

Modifying the original ODE using the eigenvalues and eigenvectors of a linearized state leads to satisfying results.

An iterative approach is presented, how to modify the original ODE, to achieve a well-damped solution.

The method can be applied for every physical resonating system, where the model complexity prevents the determination of the damping.

The iterative algorithm to modify the original ODE is novel. It can be used on different fields of the physics, where a second-order ODE is describing the problem, which has only measured or empirical damping.

With economic reforms increasing market competition, greater efficiency and productivity of factors of production, particularly of the workforce, have become important prerequisites for firms' growth and survival. Consequently, designing appropriate strategies to motivate the workforce in this direction appears as a critical aspect of human resource management. However, an important issue is if increase in wages, salaries, and other benefits can necessarily result in the desired outcomes. This chapter will examine this aspect. Estimating long-term trends in share of wages, salaries, and total emoluments in major industries, it is found that while the share of wages, salaries, and total emoluments has increased in recent years, such changes are not reflected in higher productivity. It is, therefore, suggested that, in addition to higher wages, salaries, and other benefits, enhancing efficiency and productivity of human resources requires adequate emphasis on human aspects as well.