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In semi-analytical modeling of spoke-type permanent-magnet (PM) machines (STPMM), the saturation effect is usually neglected (i.e. iron parts are considered to be infinitely permeable) and the PM magnetization is assumed tangential (i.e. magnetization pattern is considered to be tangential-parallel). This paper aims to present an improved two-dimensional (2D) subdomain technique for STPMM with the PM magnetization orientation in quasi-Cartesian coordinates by using hyperbolic functions considering non-homogeneous Neumann boundary conditions (BCs) in non-periodic regions and by applying the interfaces conditions (ICs) in both directions (i.e. t- and θ edges ICs).

The polar coordinate system is transformed into a quasi-Cartesian coordinate system. The rotor and stator regions are divided into primary subdomains, and a partial differential equation (PDE) is assigned to each subdomain. In the PM region, the magnetization orientation is considered in the equations. By applying BCs, the general solution of the equations is determined, and by applying the ICs, the corresponding coefficients are determined.

Using the proposed coordinate system, the general solution of PDEs and their coefficients can mathematically be simplified. The magnetic field and non-intrinsic unbalanced magnetic forces (UMF) calculations have been performed for three different values of iron core relative permeability (200, 800 and ∞), as well as different magnetization orientation values (135 and 80 degrees). The semi-analytical model based on the subdomain technique is compared with those obtained by the 2D finite-element analysis (FEA). Results disclose that the PM magnetization angle can affect directly the performance characteristics of the STPMM.

A new model for prediction of electromagnetic performances in the STPMM takes into account magnetization direction, and soft magnetic material relative permeability in a pseudo-Cartesian coordinate system by using subdomain technique is presented.

The purpose of this study is to investigate the factors facilitating and influencing the adoption of DevOps practices specifically tailored to mobile software development, with a focus on understanding the influence of mobile-specific requirements on DevOps integration.

The study employs a qualitative methodology, including a literature review, exploratory case research and partial quantitative assessments through DORA metrics and survey applications. This approach, guided by the Technology-Organization-Environment (TOE) framework, prioritizes in-depth insights into the adoption of DevOps practices and explores strategies for integrating DevOps in mobile software development.

The research identifies several key themes specific to Mobile DevOps adoption, including tool integration issues, testing complexities, deployment challenges and security concerns. These findings underscore the necessity for tailored DevOps solutions that can effectively address the unique demands of mobile software development. The study also proposes actionable strategies to overcome these challenges, thereby enhancing the efficiency, quality and security of mobile applications.

The insights gained from this study provide valuable guidance for practitioners in the mobile software development sector. By understanding and addressing the specific challenges of Mobile DevOps, organizations can improve their DevOps practices and achieve better outcomes in terms of project delivery speed, quality and security. For example, implementing robust testing strategies, investing in compatible tools and developing well-defined rollback procedures can significantly enhance Mobile DevOps effectiveness. Furthermore, incorporating continuous security measures and improving cross-functional collaboration can lead to more secure and efficient mobile application deployments.

This study offers valuable starting points for researching Mobile DevOps in real-world settings, based on insights from practical DevOps implementations in a single-case organization. Organizations can use this information to compare their own DevOps approaches with those of the studied organization, and can facilitate self-assessment and improvement.

This study contributes to the limited literature on Mobile DevOps adoption and proposing actionable strategies. By incorporating the TOE framework, it provides a comprehensive guide that enhances understanding and management of DevOps practices throughout the mobile application development lifecycle and offers significant value to practitioners and researchers alike.

The purpose of this paper is to understand the context of major projects and their management from an OM perspective; the authors provide a foundation for exploring how the body of work on lean production (the “old” theory) can contribute to the development of major projects (the “new” context). In doing so, it extends the prevailing economic approach to major projects (best described as “predict and provide”) and posits the development of an alternative approach based on extending the lean production logic to this new context (referred to as “predict and prevent”).

The paper investigates the scope for adopting lean practices in context of major project. To this effect the authors review the current state of both lean thinking and major project management, and use “Universal Credit” as an exploratory case study to illustrate and verify the arguments in practice.

Two main findings are proposed: first, the authors demonstrate the inherent performance challenge of major projects in OM terms, which the authors argue presents significant scope for the application of OM concepts to improve major project performance. Second, using lean thinking as framing, the authors identify three distinct process levels and common wastes in major projects, and identify five principles how lean could improve the delivery of major projects.

Major projects present an untapped area for OM research; based on the exploratory case the authors propose ways how OM concepts can be applied to this new context. Further research will be needed to validate and generalise.

Major projects, including organisational transformations, IT-enabled change, major events and large infrastructure projects, constitute a large proportion of economic activity. Despite their prominence, however, they are also commonly associated with low success rates. This paper provides one route for exploring how a successful set of principles could be applied to improving their performance.

This work translates a popular set of ideas from OM to strengthening a relatively neglected context within OM. An agenda for further research is suggested to support the development of this application.

The purpose of this study is to measure the gap and compare the quality of services provided by the Central Library of the University of Tehran and Allameh Tabataba'i University and identify the components of service that need improvement in these libraries.

In this study, a descriptive survey method is used for data collection. The study sample contains 205 people selected out of 31,000 members of Tehran University and 100 people out of 15,000 members at Allameh Tabataba'i University. The LibQual tool is used to measure different levels of users' perceptions of library service quality.

Based on the findings of the study, the level of service received at the University of Tehran was higher than the minimum expected level, and at Allameh Tabataba'i University, the level of service received was lower than the minimum level of expected, which indicates users' satisfaction at this index at the University of Tehran and users' dissatisfaction at Allameh Tabataba'i University. In the index of information control and library as a place in Tehran University, the level of service received was higher than the minimum level and in Allameh Tabataba'i University, the level of service received was lower than the minimum level, which indicates the satisfaction of users in this index at the University of Tehran and users' dissatisfaction at Allameh Tabataba'i University.

Service quality, or quality of service, is the measurement and comparison of the size of service provided with users' expectations. The following principles illustrate the dimensions of service quality: Quality of service is much more difficult to measure than the quality of goods. The quality of service is based on users' expectations. Quality of service varies in status, meaning that the quality of a service is measured against the customer's initial expectations of that service (Parasuraman et al., 1985).

Being the first performance evaluation, community synchronization, economic justification, user satisfaction and customer orientation are the values of the present study.

This paper aims to investigate the effects of boriding on the structural, mechanical and tribological properties of CoCrW dental alloy manufactured by the method of selective laser melting.

In this study, CoCrW alloy samples that are used in dentistry were manufactured by the method of laser melting, and boriding treatment was made on the samples at 900°C and 1,000°C for 1, 4 and 8 h. The structural, mechanical and tribological effects of boriding on the samples were analyzed using X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, microhardness and an abrasion test device.

According to the results, the best outcomes in terms of abrasion strength and hardness were obtained in the sample that was subjected to boriding at 1,000°C for 4 h.

This study produced CoCrW alloys, which are fundamental biomaterials that are used in dentistry, by a different production method called selective laser melting and improved their surface characteristics by boriding.

The purpose of this study is to extract the response of the simultaneous low-velocity impact of multiple impactors on a porous functionally graded (FG) aluminum plate.

To design a porous FG structure, a series of functions are applied using the porosity coefficient, and mechanical properties including Young’s modulus, shear modulus and the density of the porous structure are presented as a function of the axis placed in the direction of the plate thickness. The first-order shear deformation theory of the plate is used. To simulate the contact process between each impactor and the plate, a nonlinear Hertz contact force is considered for that impactor independently.

ABAQUS finite element software is used for the verification process of the theorical equations. The effects of porous function type, radius and initial velocity of impactor are investigated for the simultaneous impact of five impactors on porous FG aluminum plate with a simply supported boundary condition. Histories of contact force and displacement of the impactor placed in the center of the beam are analyzed in detail with the changes of the mentioned parameters.

Due to the advantages of porous aluminum plate such as high energy absorption and low weight, such structures may be subjected to the simultaneous impact of multiple impactors, which is studied in this research.

Supply of food from the early stages of societies was one of the most important needs of humans. Sustainable supply of food is a demand in modern societies. The agri-food market grows as the population rises every year. The increase in the demand side of the market is more than the growth of the supply side. The rate of using technology in the supply side is increasing rapidly. By using technology in some parts, the efficiency of production improved and caused more production while resources are the same. Availability of resources in different areas causes different ways of production and nurturing innovative technologies to maintain food security. Water, soil, climate change, and growth of population are drivers of using technology in food security. To depict the role of different technologies in the food industry, the authors have reviewed the role of the most important technologies in this field. Knowing the trends of changes in the industry will help to focus on the most important questions and solutions. Having a share in the global food market requires the major use of technology in production processes. In this chapter, the authors will review the most important trends of technology absorption in the food industry.

Financial anxiety has become a global concern and a growing research area with significant potential to contribute to the behavioral and personal finance literature. Despite this, the literature is fragmented and inconsistent. Prior studies vary greatly in the breadth of definitions and measures of financial anxiety. There has been no systematic evaluation of literature on financial anxiety antecedents, consequences, and coping strategies. This systematic review fills this gap.

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched Scopus and Web of Science and identified 55 eligible studies published between 2009 and 2024.

Financial anxiety is defined and measured differently in different research domains. We identified several antecedents, including socio-demographic factors (e.g. gender, age, ethnicity, income, employment, racial background, and language proficiency), personality traits, compulsive and impulsive buying behavior, depression or other mental issues, family health issues, and the COVID-19 pandemic and consequences of financial anxiety, including psychological and psychic health, societal and personal relations, financial behavior and well-being, and job-related outcomes. In addition, the literature presents six financial anxiety coping strategies (self-imposed coping mechanisms, spiritual and theological resources, increased financial capability, social and family support, seeking professional help, and language proficiency training). Several future research directions are presented.

This review represents the first systematic compilation and evaluation of the research findings on financial anxiety.

In this work, the effect of porosity volume fraction, porosity types, material grading index, variable disk profiles and aspect ratio on disk performance was studied by performing limit elastic speed analysis of functionally graded porous rotating disks (PFGM) under thermo-mechanical loading.

The composition change was varied by employing the power law function. The thermo-mechanical properties of PFGM such as Young's modulus and yield strength were estimated using modified rule of mixture, for density and coefficient of thermal expansion rule of mixture was used. The even and uneven distribution of porosity in a disk was taken as uniform, symmetrical, inner maximum and outer maximum. The problem was then solved with the help of the variational principle and Galerkin's error minimization theory.

The research reveals that the grading parameter, disk geometry and porosity distribution have a significant impact on the limit elastic speed in comparison to the aspect ratio.

The study determines a range of operable speeds for porous and non-porous disk profiles that the industry can utilize to estimate structural performance.

A finite element investigation was conducted to validate the findings of the present study. Limit elastic analysis of porous FG disks under thermo-mechanical loading has not been studied before.

This paper aims to propose a new unified and non-ideal switch model for analysis of switching circuits.

The model has a single unified structure that includes all possible states (on, off) of the switches. The analysis with the proposed switch model requires only one topology and uses the single system equation regardless of states of switches. Moreover, to improve accuracy, the model contains the on-state resistance and capacitive effect of switches. The system equations and the states of switches are updated by control variables, used in the model.

There are no restrictions on circuit topology and switch connections. Switches can be internally and externally controlled. The non-ideal nature of the model allows the switch to be modeled more realistically and eliminates the drawbacks of the ideal switch concept. After modeling with the proposed switch model, a linear circuit is obtained. Two examples related to switching circuits are included into the study. The results confirm the accuracy of the model.

This paper contributes a different switch model for analysis of switching converters to the literature. The main advantage of the model is that it has a unified and non-ideal property. With the proposed switch model, the transient events, like voltage spikes and high-frequency noises, caused by inductor and capacitor elements at switching instants can be observed properly.