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The fundamental period of the structure plays an important role in the seismic analysis. This study aims to analyze the modal response of dam, the two-dimensional (2D) FEM model is developed by using ANSYS 2022 R1 software.

To examine the optimized mesh size to achieve grid independence, the variable element size has been considered, and its optimal value is calculated using the technique of response surface optimization. Further, the effect of damping ratios of 5%, 8% and 10% is also considered for the free vibration analysis of the dam structure.

The results show that the natural frequencies of the dam decrease with a reduction in stiffness of the whole structure. Further, the effect of pre-stress conditions is analyzed and the study has proved that the natural frequency increases after considering the pre-stress as initial condition during modal analysis. Further, it is found that the damping has a substantial effect on frequency for higher modes of vibrations.

The study only focused on modal analysis of the gravity dam, and this study’s results can be used further to evaluate the dynamic behavior of the dam including hydrodynamic conditions.

The finite element tool is used to evaluate the modal response of gravity dam incorporating pre-stress and damping ratio along with soil–structure interaction. Moreover, to the best of the authors’ knowledge, no earlier study has been conducted to evaluate the effect of damping and pre-stress conditions on the stability and natural frequency of the system.

An electrorheological (ER) fluid consists of dielectric particles blended in a nonconducting oil. ER lubricants are often considered smart lubricants. This paper aims to examine the steady state and dynamic response of multilobe journal bearings using an ER lubricant.

Reynold’s equation has been used to describe the lubricant flow in the journal-bearing clearance space. The Bingham model is used to characterize the nonlinear behavior of the lubricant. The solution of the Reynolds equation is obtained using the Newton–Raphson method, with gaseous cavitation in the fluid film numerically addressed by applying a mass-conserving algorithm. The effects of lobe geometry and the applied electric field are investigated on film pressure profile, fluid film thickness, direct stiffness and damping parameters. The equation of motion for journal center coordinates is solved using the fourth-order Runge–Kutta method, to predict journal center motion trajectories.

Using ER lubricant combined with two-lobe journal bearing significantly improved the minimum film thickness by 49.75%, the direct stiffness parameter by 132.18% and the damping parameter by 206.3%. However, the multilobe configuration was found to negatively impact the frictional powerloss of the bearing system. In the case of multilobe configurations of journal bearings using ER lubricant, linear motion journal trajectories are observed to be reduced and exhibit increased stability.

This study presents the effect of an ER lubricant and multilobe configuration on the rotor-dynamic performance and stability analysis of hydrodynamic journal bearings.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2024-0201/

The purpose of this study is twofold. Firstly, the authors have conducted a systematic investigation considering the historical pandemic periods (1991–2021) over 30 years to identify critical factors and business failure phenomenon during pandemics to explore “what”, “why” and “how” factors contributing to business failure during the COVID-19 pandemic and secondly identified interlinks of these factors to explain the phenomenon of business failure strategically through various quantitative models.

Firstly, the critical factors were identified through previous literature and systematically reported in accordance with the PRISMA guidelines. To remove any bias in critical factor selection, Delphi method was employed. In the second phase, m-TISM approach was adopted to understand the interrelationships of the factors to develop the hierarchy levels. Lastly, MICMAC analysis was also done to evaluate the driving and dependence powers of the critical factors. For implementation of the stated methodology, expert opinion was collected to assess the critical factors based on their knowledge and experience. A total of seven experts were involved in this study.

Two major takeaways from the results of phase one were that “external environmental changes” was at the highest level and had the highest driving power as well as the lowest dependence power, while “inappropriate marketing techniques” was at the lowest level and had the highest dependence and lowest driving powers.

The ever-developing digital technologies act as a synonym to innovation and are shaping up to be the key to future-proofing any industry. However, before one can move towards developing effective strategies to mitigate any business disruptions, there is a need to assess the causes of business failures in the first place which is a major managerial implication identified through this study.

This paper can be considered as the first few studies to conduct a systematic investigation considering the historical pandemic periods (1991–2021) over 30 years to identify critical factors and business failure phenomenon during pandemics to explore “what”, “why” and “how” factors contributing to business failure during the COVID-19 pandemic and secondly identified interlinks of these factors to explain the phenomenon of business failure strategically through various quantitative models.

Metaverse is one of the technologies that has the most promise for the future. However, there is less discussion about teaching using the metaverse. It is possible that most of the educators are ignorant of the metaverse’s features and its potential uses. The objective of this chapter is to define the metaverse precisely and discusses the various applications, characteristics, and challenges of metaverse in Education. This chapter explores the pioneering efforts in leveraging the metaverse for educational purposes, highlighting key examples and their impact on the learning experience. The possible applications of metaverse and research encounters in context to education are further reviewed and then explained and included the Artificial Intelligence (AI) functions in the world of metaverse along with learning based on metaverse. Researchers in the domains of educational technology and computer science shall advance an inclusive insight of the metaverse and its potential applications in education using various metaverse techniques like gamified learning, virtual learning, etc. Also, the metaverse role in education starting from the perception of AI has been covered.

In this chapter, we describe the importance of good governance in the metaverse. It offers unlimited opportunities and presents unique governance challenges. First, we describe the concept of good governance and its relevance to the metaverse. We emphasize that the speed of metaverse adoption depends upon the presence or absence of effective governance. Recognizing the metaverse as the next iteration of the internet, we present significant governance issues. Some issues such as interoperability, security, safety, privacy, law, and digital inequality are critical governance issues in the metaverse. Next, we explore the diverse governance frameworks to ensure the implementation of policies and regulations. These frameworks include decentralized governance, cross-sector collaboration, and standards-based governance. We also describe the best practices which are essential for good governance. To materialize the concepts and principles discussed, we present a compelling case study centered on Decentraland. This insightful exploration dissects a decentralized autonomous organization (DAO)-based governance structure, offering valuable insights into the intricacies and stages of governance proposals. We acknowledge both the merits and potential drawbacks inherent to this approach. This chapter aims to offer an all-encompassing view of metaverse governance, essentially serving as a comprehensive roadmap for traversing the multifaceted landscape of this digital frontier.

As the Metaverse emerges as a prominent paradigm, Artificial Intelligence (AI) plays a pivotal role in shaping its landscape. This chapter explores the convergence of AI and the Metaverse, exploring the symbiotic relationship between these two transformative technologies. From virtual assistants to immersive experiences, AI-driven innovations are redefining how individuals interact and navigate within the Metaverse. This chapter also assesses the challenges and prospects brought about by AI in the Metaverse which is impacting both businesses and society on a broader scale.

This chapter takes on the role of the metaverse in skill development, such as skilling, reskilling, and upskilling in the digital age. Metaverse is instrumental in revolutionizing skill development in the digital age and bringing the paradigm shift in learning. This chapter will cover the capability of the metaverse to transform the ways of learning and developing skills in the evolving digital landscape. Individuals can be part of tailor-made solutions for their needs through innovative methodologies and interactive experiences. This chapter takes through real cases to get deeper insights about conventional methods that transform how an individual experiences learning to acquire skills to get exposed to the rapidly changing digital world, allowing people to customize their learning experiences to adapt their unique requirements through cutting-edge methodologies and digitally responsive encounters. It then deliberates the importance of the metaverse in the individual-led industry in a manner that allows people to reach their potential. Individuals succeed in the evolution of the metaverse dynamic by continually upskilling granted to them.

The Metaverse, an emergent Web 3.0 platform, offers users immersive virtual reality experiences. This study employs a case study approach to explore the concept of sustainability within the Metaverse. It examines the environmental, social, and economic implications of virtual interactions and the role of sustainable technologies in shaping user behavior and virtual economies. Through selected case studies, the research provides insights into the potential and challenges of integrating sustainable practices in the Metaverse, with implications for stakeholders ranging from policymakers to end-users.

In this chapter, we explore the dark side of the metaverse and the need for user protection. While the metaverse offers multiple opportunities it also poses significant risks for users, such as privacy concerns, addiction, harassment, and cyberbullying. First, we discuss the various threats that users may encounter such as online harassment, assaults, cyberbullying, hate speech, identity theft, and virtual property theft. As per the Center for Countering Digital Hate, an incident of violation occurs every seven minutes within VRChat, a popular virtual reality game. The level of misconduct in the metaverse can surpass the extent of internet harassment. Virtual reality gaming has been associated with various health issues like sleep deprivation, and insomnia as well as mental health concerns such as depression, anger, and anxiety. We examine how these issues may impact user’s physical and mental health. The sensors and devices used in the metaverse collect a vast amount of user biometric data and spatial data. Interactions between users and metaverse could be leaked. We examine different methods that improve user protection, including everyone from enhanced security protocols via the application of privacy-enhanced technology to several avatars, two-factor authentication, and user educational and awareness programs. Moreover, we explore how the newest technologies, like blockchain and artificial intelligence, play a role in making user safety more important. We finished the course with the study of the case of Second Life, the virtual reality gaming platform, and pointing out some of the problems that exist within it.