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Presents an approach to determine sources of cogging torque harmonics in permanent magnet electrical machines on the basis of variations of air‐gap magnetic flux density with time and space. The magnetic flux density is determined from the two‐dimensional (2D) finite element model and decomposed into the double Fourier series through the 2D fast Fourier transform (FFT). The real trigonometric form of the Fourier series is used for the purpose to identify those space and time harmonics of magnetic flux density whose involvement in the cogging torque is the greatest relative contribution. Carries out calculations for a symmetric permanent magnet brushless machine for several rotor eccentricities and imbalances.

Synchronous Reluctance (SynRel) motors are known to suffer from excessive torque ripples. The classical way to avoid this drawback of the motor is skewing the slots. This paper aims to provide an analytic estimation of the best skew angle to minimize the ripples in such SynRel motors with tooth windings. The approach used in this paper consists of the minimization of the spectral components of the magnetic energy that cause these oscillation torques. The method was validated by means of a multi-slice finite element model (FEM).

An analytic model, based on permeance theory, is derived to analyse the electromagnetic phenomena taking place inside of the motor. This model allows the identification of the causes underlying the torque ripple production. Based on this understanding, the most suitable skew angle can be determined. The analytic method, together with the best skew angle, is validated by means of an FEM of a SynRel machine.

A method to determine the optimum skew angle for a SynRel machine is presented. It depends on the wave-number of the magnetic waves producing the torque ripple. It is twice the one typically chosen for induction machines.

The proposed approach allows improving on the design methodology for the production of smoothly running SynRel machines.

The methodology utilized in this paper is based on the relationship between the mechanical torque and the magnetic energy stored in the motor (virtual work law). From this, the best skew angle to eliminate the magnetic energy causing torque ripple can be determined. It, therefore, proposes an effective alternative to the common use of inductance models to determine such angles.

This paper aims to present an analytical method, which combines the complex permeance (CP) and the superposition concept, to predict the air-gap magnetic field distribution in surface-mounted permanent-magnet (SMPM) machines with eccentric air-gap.

The superposition concept is used twice; first, to predict the magnetic field distribution in slot-less machine with eccentric air-gap, the machine is divided into a number of sections. Then, for each section, an equivalent air-gap length is determined, and the magnetic field distribution is predicted as a concentric machine model. The air-gap field in the slot-less machine with eccentricity can be combined from these concentric models. Second, the superposition concept is used to find the CP under eccentricity fault. At this end, the original machine is divided into a number of sections which may be different from the one for slot-less magnetic field prediction, and for each section, the CP is obtained by equivalent air-gap length of that section. Finally, the air-gap magnetic field distribution is predicted by multiplying the slot-less magnetic field distribution and the obtained CP.

The radial and tangential components of the air-gap magnetic flux density are obtained using the proposed method analytically. The finite element analysis is used to validate the proposed method results, showing good agreements with the analytical results.

This paper addresses the eccentricity fault impact upon the air-gap magnetic field distribution of SMPM machines. This is done by a combined analysis of the complex permeance (CP) method and the superposition concept. This contrasts to previous studies which have instead focused on the subdomain method.

The purpose of this paper is to minimize the torque pulsation in Halbach array permanent magnet synchronous machines (PMSMs).

Because of its specific structure, the cogging torque influences the main part of the torque pulsation in a Halbach array PMSM. In this paper, first it is shown that the conventional magnet skewing method does not have a significant effect on the torque pulsation in this motor, and then an improved skewing method with fewer skewing steps is proposed. In this method permanent magnet segments are placed sinusoidally, with two‐step skewing along the rotor. Generalization with different combinations of slots and poles is considered for a Halbach array PMSM.

Using a detailed finite element method (FEM) it was found that with the proposed technique the cogging torque factor is reduced to as low as 8 percent, while the average value of the torque is maintained near the machine nominal average torque.

Halbach array PMSMs are very good candidates for high dynamic performance applications such as aerospace applications due to their high acceleration and deceleration features. This technique also resolves the mechanical vibration and acoustic noise issues, which are caused by torque pulsation and significantly affect machine performance.

The originality of this paper lies in the FEM results. Since Halbach array PMSMs have a special structure it was shown that the conventional skewing method does not work well for this machine. The new proposed technique has a significant effect on the torque pulsation.

The purpose of this paper is to shed light on the formal and informal governance mechanisms of state-owned enterprises operating in a post-transitional economy of Poland.

The study combines legal analysis of Polish regulations in force, review of literature on the Poland’s institutional legacy, and a statistical analysis, based on a data set of 204 management board members, 180 external supervisory board members, and 114 state officials supervising Polish SOEs in 2011.

Legally designed relationships among the management board, supervisory board, and the state treasury, represented by the minister and ministry officials, constitute the key formal governance mechanisms in Polish SOEs. They are, however, complemented by relationships between SOEs and their stakeholders and distorted by other informal phenomena, including informal noninstitutional behavior, mechanisms grounded in cognitive and normative institutions, and perception of the relationship structure by the actors themselves. As a result, key corporate governance actors differ in their perception of governance influences upon SOEs.

This study contributes to policymaking by helping authorities gain a better understanding of the governance challenges in SOEs.

This paper is one of the first and few empirical studies investigating the issue of formal and informal governance mechanisms in SOEs in post-transitional economies of CEE.

The research investigates the impact of concrete design methods on performance, emphasizing environmental sustainability. The study compares the modified Bolomey method and Abrams’ law in designing concretes. Significant differences in cement consumption and subsequent CO2 emissions are revealed. The research advocates for a comprehensive life cycle assessment, considering factors like compressive strength, carbonation resistance, CO2 emissions, and cost. The analysis underscores the importance of evaluating concrete not solely based on strength but also environmental impact. The study concludes that a multicriteria approach, considering the entire life cycle, is essential for sustainable concrete design, addressing durability, environmental concerns, and economic factors.

The study employed a comprehensive design and methodology approach, involving the formulation and testing of 20 mixed concretes with strengths ranging from 25 MPa to 45 MPa. Two distinct design methods, the modified Bolomey method (three equations method) and Abrams’ law, were utilized to calculate concrete compositions. Laboratory experiments were conducted to validate the computational models, and subsequent analyses focused on assessing differences in cement consumption, compressive strength, CO2 emissions, and concrete resistance to carbonation. The research adopted a multidisciplinary perspective, integrating theoretical analysis, laboratory testing, and life cycle assessment to evaluate concrete performance and sustainability.

Conclusion from the study includes substantial variations (56%–112%) in cement content, depending on the calculation method. Abrams' law proves optimal for compressive strength (30 MPa–45 MPa), while the three equations method yields higher actual strength (30%–51%). Abrams' law demonstrates optimal cement use, but concrete designed with the three equations method exhibits superior resistance to aggressive environments. Cement content exceeding 450 kg/m³ is undesirable. Concrete designed with Abrams' law is economically favorable (12%–30% lower costs). The three equations method results in higher CO2 emissions (38–83%), emphasizing the need for life cycle assessment.

This study’s originality lies in its holistic evaluation of concrete design methods, considering environmental impact, compressive strength, and cost across a comprehensive life cycle. The comparison of the traditional Abrams' law and the three equations method, along with detailed laboratory tests, contributes novel insights into optimal cement use and concrete performance. The findings underscore the importance of a multicriteria approach, emphasizing sustainability and economic viability. The research provides valuable guidance for engineers and policymakers seeking environmentally conscious and economically efficient concrete design strategies, addressing a critical gap in the field of construction materials and contributing to sustainable infrastructure development.

Social marketing theories have habituated to a theoretical and methodological focus that is criticised for being myopic and stigmatising. Following recommendations to redirect focus theoretically, the purpose of this paper is to apply an observational methodology to understanding how project stakeholders interact to examine whether consideration of stakeholders can identify factors facilitating or impeding farming practice change.

More than 48 events involving as many as 150 people including project stakeholder meetings, one-on-one consultations and annual events were observed over more than 100 h by between one and five researchers. Field notes were gathered, and thematic coding focussed on understanding how stakeholders facilitated or impeded practice change.

Observations identified limited provision of information about the project by on ground project stakeholders to targeted individuals (farmers). On the rare occasions where information sharing was observed, communication was delayed making it difficult for individuals to connect actions with outcomes observed. Participating stakeholders did not freely support delivery of activities needed for individual practice change.

This study indicates the value of wider process and outcome assessment encompassing stakeholders to identify factors impeding and facilitating farming practice change.

Approaches that centre attention on individuals fail to acknowledge the inputs, activities and outputs delivered by project stakeholders within a system of change. By redirecting evaluation focus, shared responsibility is gained and stigmatisation of one stakeholder group can be avoided.

This study demonstrates how observations can be used to redirect focus to consider actions and interactions occurring between on ground project stakeholders. A stakeholder evaluation approach extends monitoring and evaluation focus beyond individuals targeted for behaviour change. Implications, limitations and future research directions are outlined.

The U.N.’s perseverance in fostering sustainable industrialisation has not rendered the expected results in the long run. Despite that the scope of SDG9 is reasonably well defined and communicated, there is much more to be done to make it a reality. Achievements on SDG9 have not been as positive as they might have. It should be noted that there is no trustworthy source of information that indicates with certainty the progress towards the 2030 agenda. The purpose of this chapter is to examine factors involved in the SDG9 reporting and other critical issues necessary to understand the progress and how we are progressing towards SDG9. From this point on, data for our debate come from several sources. Still, the primary outcomes come from the 2017 High-level Political Forum on Sustainable Development, the Sustainable Development Goals Report 2020, the 2020 Voluntary National Reviews (VNRs) independent assessment, and other Sustainable Development Goals (SDGS) reports as well as scientific literature. Unfortunately, there appears to be a lack of reliable SDG9 information available, and what exists is hard to find. In general, information sources often offer qualitative information, and quantitative data are scarce. This situation is especially the case for the documents presented in the chapter, which provided a few statistics disaggregate data, making it challenging to analyse in-depth. The debate here presented does not seek to be a fully comprehensive assessment of their content. The analysis is not designed to interpret or replace the referenced documents, either. Instead, it is intended to illustrate the difficult task of measuring the progress towards SDG9.

Family businesses must be examined within the cultural contexts in which they are bred, nourished, and grown. According to Chrisman, Chua, and Steier (2003), family businesses are launched for reasons other than the desire for dollars and cents (or rupees and yen). In fact, the authors note, “Family businesses… bring together so starkly the economic and non-economic realities of organizational life…” (2003, p. 442). Calls for family business research that extend beyond traditional geographical boundaries to include global comparisons have been issued by Hoy (2003) and others. Fortunately, recent developments in cultural assessment and measurement methodology have provided tools to enable a better understanding of families and family businesses vis-à-vis the use of regional clusters and comparative lenses (Gupta & Hanges, 2004). Gupta and Hanges (2004) note three clusters of the Catholic ethic: Southern (or Latin) Europe, Latin America, and Eastern Europe. As shown in Table 1, more than three-fourths of the population in these clusters follows the Catholic faith. In this study, we examine the spirit of family business in these three clusters.