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Several effects of the atmosphere in the soldering oven on both the soldering process itself and the soldering results are discussed. Experiments have been undertaken to compare the results of soldering in air and in nitrogen containing 10,100 and 1000 ppm oxygen, in which, e.g., discolouration, wettability, solderability after reflow, solder bridging and solder‐ball formation were investigated. Unmounted FR‐4 testboards with both an RMA solder paste of known high quality and a low‐residue paste were used. Mounted test boards were used to analyse the self‐alignment of components and to compare the levels of soldering defects obtained in air and in nitrogen. The test results show that a nitrogen atmosphere containing 1000 ppm of oxygen or less is sufficiently pure to realise improved soldering conditions for most types of components. For the low‐residue paste tested, 1000 ppm is too high, but 100 ppm is sufficiently low. All effects on the soldering process will depend on the amount of oxygen in the gas. To produce an oven atmosphere of nitrogen with a very low amount of O2 (e.g., <100 ppm) is rather expensive, if this oven is to work under production conditions. Will the extra cost of investment and gas consumption be worthwhile in view of a better production yield and higher product quality? The authors explain why they do not believe this to be the case.

Isometric feature mapping (Isomap) is a very popular manifold learning method and is widely used in dimensionality reduction and data visualization. The most time-consuming step in Isomap is to compute the shortest paths between all pairs of data points based on a neighbourhood graph. The classical Isomap (C-Isomap) is very slow, due to the use of Floyd’s algorithm to compute the shortest paths. The purpose of this paper is to speed up Isomap.

Through theoretical analysis, it is found that the neighbourhood graph in Isomap is sparse. In this case, the Dijkstra’s algorithm with Fibonacci heap (Fib-Dij) is faster than Floyd’s algorithm. In this paper, an improved Isomap method based on Fib-Dij is proposed. By using Fib-Dij to replace Floyd’s algorithm, an improved Isomap method is presented in this paper.

Using the S-curve, the Swiss-roll, the Frey face database, the mixed national institute of standards and technology database of handwritten digits and a face image database, the performance of the proposed method is compared with C-Isomap, showing the consistency with C-Isomap and marked improvements in terms of the high speed. Simulations also demonstrate that Fib-Dij reduces the computation time of the shortest paths from O(N³) to O(N²lgN).

Due to the limitations of the computer, the sizes of the data sets in this paper are all smaller than 3,000. Therefore, researchers are encouraged to test the proposed algorithm on larger data sets.

The new method based on Fib-Dij can greatly improve the speed of Isomap.

The chapter provides recommendations for key communicators’ social media use during pandemic threats. Recommendations are based on findings from two sets of case studies during the 2014–2015 outbreak of Ebola in West Africa: the use by authorities in UK and Norway during the 2014–2015 West African Ebola outbreak; and the use by established media in the UK.

Metaverse, that is extended reality (XR)-based technologies such as augmented reality (AR) and virtual reality (VR), are increasingly believed to facilitate fundamental human practice in the future. One of the vanguards of this development has been the consumption domain, where the multi-modal and multi-sensory technology-mediated immersion is expected to enrich consumers' experience. However, it remains unclear whether these expectations have been warranted in reality and whether, rather than enhancing the experience, metaverse technologies inhibit the functioning and experience, such as cognitive functioning and experience.

This study utilizes a 2 (VR: yes vs no) × 2 (AR: yes vs no) between-subjects laboratory experiment. A total of 159 student participants are randomly assigned to one condition — a brick-and-mortar store, a VR store, an AR store and an augmented virtuality (AV) store — to complete a typical shopping task. Four spatial attention indicators — visit shift, duration shift, visit variation and duration variation — are compared based on attention allocation data converted from head movements extracted from recorded videos during the experiments.

This study identifies three essential effects of XR technologies on consumers' spatial attention allocation: the inattention effect, acceleration effect and imbalance effect. Specifically, the inattention effect (the attentional visit shift from showcased products to the environmental periphery) appears when VR or AR technology is applied to virtualize the store and disappears when AR and VR are used together. The acceleration effect (the attentional duration shift from showcased products to the environmental periphery) exists in the VR store. Additionally, AR causes an imbalance effect (the attentional duration variation increases horizontally among the showcased products).

This study provides valuable empirical evidence of how VR and AR influence consumers' spatial bias in attention allocation, filling the research gap on cognitive function in the metaverse. This study also provides practical guidelines for retailers and XR designers and developers.

The chapter focuses on how engaging undergraduate and graduate students at a metropolitan university through community-based experiential learning can help them make a difference in their personal relationships, in their workplaces and in their communities.

The chapter explores the University of Arkansas at Little Rock Department of Speech Communication’s integrated approach to undergraduate and graduate curriculum that focuses on four types of casing complex problems and making positive, ethical recommendations to make a difference. Specifically, the chapter explores how problem-based learning; service-learning; narrative ethnography; and research projects can be used as meaningful ways to case complex communication issues and to make ethical, theory-informed recommendations to not only do no harm but also affect positive change and promote social justice in students’ personal relationships, organizations, and communities.

Lessons learned from the programmatic approach are shared that include building a theoretical base for students to draw from, integrating case approaches into the curriculum, and engaging resistance and failure. Chapter recommendations promote using theory as a lever for learning, building meaningful relationships with stakeholders, and adopting a process orientation that embraces failure.

The chapter offers a review of four undergraduate courses and four graduate courses, with explicit applications of the four case approaches. Additionally, learning objectives, major assignment descriptions, and assessment approaches are detailed for each course.

Interest in the Electronic Word-of-Mouth (eWOM) in connection with tourism is constantly growing not only among consumers but also among theoreticians. Therefore, the objective of this chapter is to provide an overview of studies that focus on eWOM in the tourism sector using the snowball method. The article is based on a review of the literature of 60 studies that focus not only on consumer behavior in tourism and the impact of eWOM on tourism supply but also on the impact of hotel managers' responses to other consumer behavior and tourism companies. The results of the studies show that eWOM has a significant impact not only on consumer behavior but also on tourism supply. Manager responses can also strongly affect other consumer behavior in decision-making. When eWOM is distributed, consumers are influenced by their emotions, motives, and also by the websites to which they have decided to contribute. The chapter proposes further research areas for different authors.

This chapter analyzes the campaign against race norming in the 2013 National Football League (NFL) concussion settlement that caregivers of retired players designed, and it considers how their collective action throws new light on activism in sport. While there is a substantial literature on how individual athletes engage in protest, less work has focused on how families – partners, children, siblings, and parents – of athletes organize as a group to answer back to anti-Black racism in professional sport. I argue that a group of spouses used their position as caregivers to shame the NFL, the presiding judge of the settlement, Class Counsel, and even the Department of Justice into acknowledging not only individual suffering from traumatic brain injury but also of the distribution of that suffering across households. Specifically, the wives group expanded definitions of risk and damage to include not only individual illness but also family and group suffering and demanded inclusion of gendered and racialized aspects of social care. Through their campaign, the group recast what is considered protest in the world of sport and who has the ability to access an activist subjectivity.

Based on the assumption that the identity and self-understanding of an academic discipline determines how it conceptualizes different domains of social reality, including how it imports and/or exports concepts from or to other disciplines, this chapter presents some of the findings of a major ongoing comparative and cross-disciplinary study of how five key concepts within the combined fields of crisis management and reputation management are applied in three different disciplinary contexts. In this chapter, however, the focus is on just one of these concepts: the concept of reputation.