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Ultrasonic additive manufacturing (UAM) is a rapid prototyping process through which multiple thin layers of material are sequentially ultrasonically welded together to form a finished part. While previous research into the peak temperatures experienced during UAM have been documented, a thorough examination of the heating and cooling curves has not been conducted to date.

For this study, UAM weldments made from aluminum 3003‐H18 tapes with embedded Type‐K thermocouples were examined. Finite element modeling was used to compare the theoretical thermal diffusion rates during heating to the observed heating patterns. A model was used to calculate the effective thermal diffusivity of the UAM build on cooling based on the observed cooling curves and curve fitting analysis.

Embedded thermocouple data revealed simultaneous temperature increases throughout all interfaces of the UAM build directly beneath the sonotrode. Modeling of the heating curves revealed a delay of at least 0.5 seconds should have existed if heating of lower interfaces was a result of thermal diffusion alone. As this is not the case, it was concluded that ultrasonic energy is absorbed and converted to heat at every interface beneath the sonotrode. The calculated thermal diffusivity of the build on cooling was less than 1 percent of the reported values of bulk aluminum, suggesting that voids and oxides along interfaces throughout the build may be inhibiting thermal diffusion through thermal contact resistance across the interface.

This work systematically analyzed the thermal profiles that develop during the UAM process. The simultaneous heating phenomenon presented here has not been documented by other research programs. The findings presented here will enable future researchers to develop more accurate models of the UAM process, potentially leading to improved UAM bond quality.

Interest in employee mindfulness has increased dramatically in recent years, fueled by several important conceptual articles, numerous studies documenting the benefits of mindfulness for employee outcomes, and the adoption of mindfulness-based practices in many Fortune 500 organizations. Despite this growing interest, the vast majority of research on employee mindfulness has taken an intrapersonal focus, failing to appreciate the ways in which mindfulness may enhance work-related relational processes and outcomes. The authors explore possible associations between mindfulness and relationally oriented workplace phenomena, drawing from interdisciplinary scholarship examining mindfulness in romantic relationships, child–parent relationships, patient–healthcare provider relationships, and student–teacher relationships. A framework is proposed that links mindfulness to three distinct relationally oriented processes, which are expected to have downstream effects on work-related relational outcomes. The authors then take the proposed framework and discuss possible extensions to a variety of unique workplace relationships and discuss critical next steps in advancing the relational science of mindfulness.

Through a review of historically famous cases and a chronicle of neurotechnology development, this chapter discusses brain structure and brain function as two distinct yet interrelated paths to understand the relative contributions of anatomical and physiological mechanisms to the human brain–behavior relationship. From an organizational neuroscience perspective, the chapter describes over a dozen neuroimaging technologies that are classified under four groupings: morphologic, invasive metabolic, noninvasive metabolic, and electromagnetic. We then discuss neuroimaging variables that may be useful in social science investigations, and we underscore electroencephalography as a particularly useful modality for the study of individuals and groups in organizational settings. The chapter concludes by considering emerging science and novel brain technologies for the organizational researcher as we look to the future.

This chapter introduces the book’s purpose: to explore the niche technology space of Web3 and use it as a lens to reflect on the internet’s future. I’ll discuss the internet’s current state and key issues and then move into a definitional tour of Web3 and its underlying technology. The book’s core argument is presented: Web3 provides tangible social proof of what people want for the internet’s future. I’ll examine current challenges such as privacy concerns, unclear data ownership, and lack of transparency in online systems, which create power imbalances between technology controllers and users. The book argues for striving towards a more equitable and transparent digital future. This chapter serves as a starting point, offering insight into my decade-long research. It aims to familiarise readers with the case study approach and Web3 terminology used throughout the book. A chapter-by-chapter roadmap is provided to guide readers through the exploration of Web3 and its implications. Additionally, this chapter introduces my writing style and voice, preparing readers for the deeper analysis to come. While grounded in sociological knowledge, the chapter aims to make Web3 accessible and spark readers’ curiosity, encouraging them to pursue their own inquiries into this emerging field.

Greater parental monitoring is commonly associated with reduced delinquent behavior in adolescents, yet less is known about the extent to which parental monitoring behavior changes after a child is arrested for the first time. The present study examines the extent to which mothers’ monitoring behaviors (i.e., parental monitoring knowledge and effort) change in association with juvenile recidivism after their sons’ first arrest, operationalized through both youth-reported recidivism and official re-arrest records. Mother–son dyads (total N = 634) across three states were interviewed in two waves over 30 months following the youth’s first arrest. Mothers who reported both more monitoring knowledge and effort at Wave 1 had sons who self-reported less recidivism and were less likely to be re-arrested at Wave 2. Repeated sons’ re-arrests were associated with a change in mothers’ monitoring behavior, as both parental knowledge and parental effort significantly increased from Wave 1 to Wave 2 when youth have been re-arrested more than once, relative to youth who had never been re-arrested. No change in monitoring behaviors were observed in association with youth-reported recidivism, and mothers who stated an intention to change their monitoring habits at Wave 1 did not necessarily do so by Wave 2. The findings point to the ability of parents to modulate their monitoring behavior to respond to chronic juvenile offending. This provide an opportunity for practitioners to work with parents to improve their monitoring skills, to ensure rehabilitative gains that result from justice system intervention are maintained in the home via parental monitoring.

Wire + arc additive manufacturing (WAAM) uses existing welding technology to make a part from metal deposited in an almost net shape. WAAM is flexible in that it can use multiple materials successively or simultaneously during the manufacturing of a single component.

In this work, a gas metal arc welding (GMAW) based wire + arc additive manufacturing (WAAM) system has been developed to use two material successively and fabricate bimetallic additively manufactured structure (BAMS) of low carbon steel and AISI 316L stainless steel (SS).

The interface shows two distinctive zones of LCS and SS deposits without any weld defects. The hardness profile shows a sudden increase of hardness at the interface, which is attributed to the migration of chromium from the SS. The tensile test results show that the bimetallic specimens failed at the LCS side, as LCS has lower strength of the materials used.

The microstructural features and mechanical properties are studied in-depth with special emphasis on the bimetallic interface.

This chapter seeks to reassess the film GoldenEye (Campbell, 1995), and its highly successful (Impellizeri, 2010) videogame adaptation GoldenEye 007 (Rare, 1997), in light of the concept of the Hegemony of Play (Fron, Fullerton, Morie, & Pearce, 2007), which seeks to critique the dominance of the hypermasculine ‘gamer’ identity in videogame culture (a persona GoldenEye anticipates in its problematic character Boris Grishenko).

Since the gamer is bound up in the very technological materiality of videogames as a medium and an industry (Dyer-Witheford & de Peuter, 2009), central to this discussion is the significant yet highly ambivalent role technology continues to play in the Bond films, both extending and threatening (Leach, 2015; Nitins, 2010) Bond’s natural male skill and intuition (McGowan, 2010). Indeed, GoldenEye is a particularly salient study since many suggest Brosnan to be the most technologically adept (or dependent) of the Bonds (Rositzka, 2015; Willis, 2003), and I will argue that the film and game together explore just what happens when Bond’s implacable force meets the immutable technological object, providing a fascinating lens through which to read the larger technocultural shifts embodied in the transition to the immaterial economies of cognitive capitalism (Hardt & Negri, 2001) and their potential to disrupt traditional, patriarchal gender configurations (Haraway, 1991; Hayles, 2005; Plant, 1998; Wajcman, 2004).

Core to this is a critical reading of the game’s popular multiplayer mode, where exploration of whether technology can be understood to potentially level the gender playing field (Jones, 2015) or whether the fact that such technology is always already encoded as masculine (Chess, 2017) ultimately undercuts this ambition.

This chapter addresses the question of what normatively binding claims can be associated with the principle of sustainability. It proposes a theoretical reading of justice that requires a new level of morality, namely a global (spatial), intergenerational (temporal) and ecological (material) extension of the scope of responsibility. This makes it plausible that responsibility for those who are distant in space and time, as well as for nature, becomes a matter of conscience. At the same time, it is shown how the binding claims resulting from the principle of sustainability can be internalised in the course of a conscience formation and how the gap between knowledge and action in questions of sustainable development can be closed by means of an emotional underpinning. Finally, it is proposed to transfer the question of conscience to spatial units and tourism through the model of ‘Destination Conscience’ and to institutionalise the idea of ‘inner commitment’ or self-commitment. One suggestion is the creation of committees that could be a collective ethical conscience for the future issues.

This study aims to assess the pitting resistance of austenitic stainless steel welded joints fusion zone (FZ) with high density of inclusions before and after surface treatment, including potentiostatic pulse technique (PPT) and pickling.

The potentiodynamic polarization tests and critical pitting temperature tests were carried out for estimating pitting resistance. The PPT and pickling were performed as surface treatment. Scanning electron microscope (SEM) and energy dispersive spectrometer were used for characterize the microstructure and elemental distribution. Electron back-scattered diffraction (EBSD) was used to assess the portion of phases and morphology of grains.

The weld metal exhibits a higher degree of alloying compared to the base metal, and it contains d-phase and sulfur-containing inclusions. Sulfur-containing inclusions serve as initiation sites for pitting, and they diminish the pitting resistance of weld metal. Both PPT and pickling can remove sulfur-containing inclusions, but PPT causes localized dissolution of the weld metal matrix around the inclusions, while pickling does not. Because of the high density of inclusions, certain pits initiated by PPT are significantly deeper, which makes the formation of stable pitting easier. Because of the high density of inclusions, certain pits initiated by the PPT are deeper. This characteristic facilitates the progression of these initial defects into fully developed, stable pits.

Analysis of pitting initiation in shielded metal arc welding FZ with PPT and ex situ SEM tracking observation. Explanation of why the PPT surface treatment is not able to enhance the pitting resistance of stainless steel with a high inclusion density.