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Improperly fitted parameters for the Jiles–Atherton (JA) hysteresis model can lead to non-physical hysteresis loops when ferromagnetic materials are simulated. This can be remedied by including a proper physical constraint in the parameter-fitting optimization algorithm. This paper aims to implement the constraint in the meta-heuristic simulated annealing (SA) optimization and Nelder–Mead simplex (NMS) algorithms to find JA model parameters that yield a physical hysteresis loop. The quasi-static B(H)-characteristics of a non-oriented (NO) silicon steel sheet are simulated, using existing measurements from a single sheet tester. Hysteresis loops received from the JA model under modified logistic function and piecewise cubic spline fitted to the average M(H) curve are compared against the measured minor and major hysteresis loops.

A physical constraint takes into account the anhysteretic susceptibility at the origin. This helps in the optimization decision-making, whether to accept or reject randomly generated parameters at a given iteration step. A combination of global and local heuristic optimization methods is used to determine the parameters of the JA hysteresis model. First, the SA method is applied and after that the NMS method is used in the process.

The implementation of a physical constraint improves the robustness of the parameter fitting and leads to more physical hysteresis loops. Modeling the anhysteretic magnetization by a spline fitted to the average of a measured major hysteresis loop provides a significantly better fit with the data than using analytical functions for the purpose. The results show that a modified logistic function can be considered a suitable anhysteretic (analytical) function for the NO silicon steel used in this paper. At high magnitude excitations, the average M(H) curve yields the proper fitting with the measured hysteresis loop. However, the parameters valid for the major hysteresis loop do not produce proper fitting for minor hysteresis loops.

The physical constraint is added in the SA and NMS optimization algorithms. The optimization algorithms are taken from the GNU Scientific Library, which is available from the GNU project. The methods described in this paper can be applied to estimate the physical parameters of the JA hysteresis model, particularly for the unidirectional alternating B(H) characteristics of NO silicon steel.

The aim of this study is to identify the travel constraints of people with special needs (PwSN) and the strategies used to overcome them. The article also intends to analyze the differences in travel constraints and negotiation strategies according to the type of disability and/or special need.

A qualitative study was conducted in which a sample of PwSN (people with disabilities – mobility, sensory and cognitive – seniors and people with food allergies) were interviewed in depth.

PwSN face a wide range of constraints when engaging in tourism activities. These constraints are very diverse and influence people with different intensity and have to be overcome using different negotiation strategies. However, differences in the constraints were observed according to the type of special needs.

One of the most significant practical implications of this research is the need for raising awareness regarding human diversity among tourism stakeholders. It is critical to link sectoral policies that are reflected in the social and business reality, creating public–private partnerships to raise the sharing of knowledge, equipment and services. By addressing the constraints that prevent PwSN from traveling, the tourism sector can create more opportunities for them to participate in social activities, improving their quality of life and contributing to a more sustainable and inclusive industry.

Traveling can present significant challenges for people with special needs, which affect the quality of their tourism experience. Despite growing academic attention to this issue in recent years, research in this field has primarily focused on specific aspects of disability. This study seeks not only to identify the barriers to travel faced by people with different special needs but also to explore the negotiation strategies used to overcome these barriers and the differences according to the type of special need.

The purpose of this paper is to give a comprehensive survey on the physics-based virtual assembly (PBVA) technology in a novel perspective, to analyze current drawbacks and propose several promising future directions.

To provide a deep insight of PBVA, a discussion of the developing context of PBVA and a comparison against constraint-based virtual assembly (CBVA) is put forward. The core elements and general structure are analyzed based on typical PBVA systems. Some common key issues as well as common drawbacks are discussed, based on which the research trend and several promising future directions are proposed.

Special attention is paid to new research progresses and new ideas concerning recent development as well as new typical systems of the technology. Advantages of PBVA over CBVA are investigated. Based on the analysis of typical PBVA systems and the evolution of PBVA, the core elements of the technology and the general structure of its implementation are identified. Then, current PBVA systems are summarized and classified. After that, key issues in the technology and current drawbacks are explored in detail. Finally, promising future directions are given, including both the further perfecting of the technology and the combination with other technologies.

The PBVA technology is put into a detailed review and analysis in a novel way, providing a better insight of both the theory and the implementation of the technology.

The purpose of this paper is to reveal how mental models inherited from offline retailing have impeded both the theory and practice of online retailing, and to suggest fruitful areas of research in online retailing.

The mental models of physical retail suggest physical constraints of various sorts, and yet for the most part, the constraints acting upon the e‐tailer are instead logical, symbolic and cognitive.

Researchers in e‐tailing could benefit from pursuing a set of interesting issues including assortment, customer‐to‐customer value creation, site design and structure, and the importance of network topology.

There are many new topics in retailing that can be explored by marketers, as long as we are willing to jettison some of our cherished terminology and ways of thinking. In effect, online, the retailing mix becomes human‐centric, rather than focusing on physical components.

The skill sets needed to set up an e‐tailing presence are substantially different than those required for offline retailing.

The paper takes an unconventional view of the retailing literature, literature that goes back to the foundation of marketing as an academic discipline.

This purpose of this study is to structure complex problems to be solved with greater efficiency, optimising the relationship between root causes (RC) relevance of the problem and utilisation of human resources to treat them, minimising the use of manpower in problem-solving activity and thus contributing to greater productivity within organisations.

The authors built an approach under the concepts of theory of constraints and multiattribute and multiobjective decision-making methods that were applied in a real complex problem of the low development of Brazilian space industry, by theoretical perspective. Also, the authors submitted it in a simulation environment to assess in which situations it is successful considering number of problem’s RC, system complexity and number of people in the system.

The approach was successful on the real case, finding the optimal relationship between the RC relevance and the number of people involved to treat them. For certain complex problem inputs configurations, simulation results reveal that the approach is reliable obtaining more than 95% chance of success in finding the optimal relationship, when comparing with traditional prioritising methods.

This approach introduces an unprecedented way to locate and evaluate non-physical constraints within a system, which is used to determine RC relevance, as well as an unprecedented way of defining a single optimal solution for structuring a problem, considering the relevance of RC and the use of human resources. The approach is useful for organisations in general which often need managing complex problems with few resources.

The purpose of this paper is to present a dual-mode online optimization method (OOM) for trajectory tracking of the redundant manipulators. This method could be used to resolve the problem of the kinematics redundancy effectively when the manipulator moves in a limited space or its movements go through a singular point.

In the proposed method, the physical limits of the manipulator in the torque level is considered as inequality constraints for the optimal scheme. Besides, a dual-mode optimal scheme is developed to yield a feasible input in each control period during the path tracking task of the manipulator, especially when it moves under the limited space or around the singular point. Then, the scheme is formulated as a quadratic programming; the computationally efficient quadratic programming solver based on interior method is formulated to solve the kinematic redundancy problem.

The traditional pseudo inverse method (PIM) for the kinematic resolution to the redundant manipulator has some limitations, such as slow computation speed, unable to take joint physical limits into consideration, etc. Relatively, the OOM could be used to conquer the deficits of the PIM method. Combining with the dual-mode optimal scheme and considering the physical constraints in the torque level, the online method proposed in this paper is more robust and efficient than the existing method.

In this paper, dual-mode OOM is first proposed for the resolution of the kinematics redundancy problem. Specific design of its model and the discussion of its performance are also presented in this paper.

The purpose of this paper is to present a comprehensive descriptive analysis of the sequential application of the Theory of Constraints (TOC) five‐step focusing process in improving the effectiveness of a service process that was limiting the performance of the entire service system.

The five‐step approach is schematically presented with each step being described and evaluated relative to its role in effective constraint management. A detailed example provides additional insights and nuances into its use in managing the constraint within a banking organization's subsystem, namely, the loan application and approval process. This hypothetical, realistic, and comprehensive illustration iterates through several cycles of the five‐step focusing process to demonstrate how managers are able to address different types of constraints.

The paper provides a detailed description on how each of the five‐steps can be used to improve the organization's performance relative to its stated goal by focusing management's attention on the system's (or an aligned subsystem's) leverage or control point. Major types of constraints include physical or capacity limitations and restrictive policies. Constraints may be located either internal or external to the process or system being managed.

Various managerial implications are discussed including: the relevance and utility of applying the TOC five‐step focusing process in services; advantages associated with utilizing this structured approach for continuous improvement in services; and some strategic issues associated with the placement of the ubiquitous system constraint.

Although the successful application of the five‐step focusing process has been well documented in improving manufacturing processes, this paper provides an illustrative tutorial which details its application in effectively managing a service process.

Theory of Constraints (TOC), though a well-established process improvement methodology in manufacturing, is still a novel philosophy for healthcare and an exhaustive review of literature is needed to summarize the key findings of various researchers. Such a review can provide a direction to the researchers and academicians interested in exploring the application of TOC in the healthcare sector. This paper aims to review the existing literature of TOC tools and techniques applied to the healthcare environment, and to investigate motivating factors, benefits and key gaps for identifying directions for future research in the domain of healthcare.

In this paper, different electronic repositories were searched using multiple keywords. The current study identified 36 articles published between January 1999 to mid-2021 to conceptualize and summarize the research questions used in the study. Descriptive analysis along with pictorial representations have been used for better visualization of work.

This paper presents a thorough literature review of TOC in healthcare and identifies the evolution, current trends, tools used, nature of services chosen for application and research gaps and recommends future direction for research. A variety of motivating factors and benefits of TOC in healthcare are identified. Another key finding of this study is that almost all implementations listed in literature reported positive outcomes and substantial improvements in the performance of the healthcare unit chosen for study.

This paper provides valuable insight to researchers, practitioners and policymakers on the potential of TOC to improve quality of services, flow of patients, revenues, process efficiency and cost reduction in different health care settings. A number of findings and suggestions compiled in the paper from literature study can be used for diagnosing, learning and making substantial changes in healthcare. The methodologies used by different researchers were analysed and combined to propose a generic step by step procedure to apply TOC. This methodology will guide the practising managers about the appropriate tools of TOC for their specific need.

Good health is always the first desire of all men and women around the globe. The global aim of healthcare is to quickly cure more patients and ensure healthier population both today and in future. This article will work as a foundation for future applications of TOC in healthcare and guide upcoming applications in the booming healthcare sector. The paper will help the healthcare managers in serving a greater number of patients with limited available resources.

This paper provides original collaborative work compiled by the authors. Since no comprehensive systematic review of TOC in healthcare has been reported earlier, this study would be a valuable asset for researchers in this field. A model has been presented that links various benefits with one another and clarifies the need to focus on process improvement which naturally results in these benefits. Similarly, a model has been presented to guide the users in implementation of TOC in healthcare.

The purpose of this paper is to investigate how digital and physical product development can be successfully coordinated and which new product development and contextual practices are suitable for the combined digital-physical product development process.

The paper is based on a multiple-case study within one company with three digital-physical product development projects as the units of analysis. The data collection and analysis are guided by an existing research model. The case study is used deductively to illustrate the model.

When combining digital and physical development processes, one or both need to change. This may lead to sub-optimization of one or both of the processes but optimizes the combined digital-physical process. Various development and coordination practices as well as contextual measures must be put into place to improve fit to the digital-physical process characteristics and mixed materiality.

The paper illustrates the research model with case evidence and suggests tentative theory in the form of propositions. Further research needs to explore the impact of the practices and contextual measures proposed.

This research proposes a range of conditions facilitating the successful development of digital-physical products.

This paper is among the first to empirically explore the complex process of digital-physical product development. Taking a process perspective and focusing on organizational and managerial practices and the influence of context, organization theory is used as the theoretical lens.