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To evaluate the oxide formation characteristics of tin (Sn) as a function of conditioning treatment and define a conditioning methodology that rapidly produces a tin oxide thickness and oxide species morphology similar to those formed in ambient oxidation.

Electrochemical reduction analysis and scanning electron microscopy techniques were utilized to identify tin oxide species and oxide quantities on tin samples which were subjected to a variety of conditioning methodologies.

Tin oxide species were identified and oxide quantities measured. Comparisons of tin oxide species/quantities were completed for the different conditioning methodologies used and for other industry oxide investigations. The following conclusions were reached: all conditioning methodologies produced both SnO and SnO₂ tin oxide species; steam conditioning produced the thickest oxides; the conditioning methodologies investigated were found to produce oxide thicknesses similar to those formed under ambient conditions.

Further investigation would be beneficial using this study as a foundation. Additional conditioning methodologies and a larger selection of various tin surfaces would provide a future understanding of the impact of oxide species and thickness on solderability.

The electronics industry has attempted to “predict” a surface's susceptibility to oxidation by using accelerated conditioning techniques. An understanding of the formation of tin oxidation products created by accelerated conditioning techniques could be highly beneficial to the electronics industry. The standardization and use of a realistic accelerated conditioning technique would reduce testing cycle time, increase the predictability and consistency of test results, and lower testing costs.

This paper was incorporated into an original electronics manufacturer's solderability testing/analysis procedures, and the results are being utilized by the electronics industry solderability specification task groups/committees.

The purpose of this paper is to establish greater understanding of changes in gender diversity at the undergraduate, graduate and faculty levels for a small engineering discipline, materials science and engineering (MSE), and how it may be related to different cultures across the variety of engineering disciplines.

The paper assesses publicly available data on the demographics of US MSE programs to explore expectations of correlation between increased gender diversity at the graduate level and among faculty versus undergraduate gender diversity.

The number and percentage of women increased substantially in graduate programs and within faculties whereas the percentage of women receiving bachelor's of science degrees in engineering (BSE) in MSE, and nearly all other engineering disciplines, was significantly lower in 2009 than in 2000. Diversity advances at graduate, postdoctoral and faculty levels in the interdisciplinary field of MSE, and likely other relatively young engineering disciplines, have been achieved via a continuous migration of individuals from other science and engineering disciplines as well as from international science and engineering programs.

The paper does not explore cause‐and‐effect, but rather provides a case study of trends occurring within a specific discipline. When evidence for a “leaky pipeline” is found within one generalized context (i.e. engineering), the assumption has been that every discipline (i.e. MSE, biomedical engineering) within that context has leaky pipelines that must be fixed. Given the present data, such assumptions may be inappropriate and perpetuate an understanding of how to improve gender diversity that is not helpful and, in fact, may be harmful to achieving diversity.

The paper provides an assessment of gender diversity for a smaller discipline and explores applicability of conventional pipeline models for career progression.

This paper aims to evaluate the morphology and thickness of oxides that form on the surfaces of tin whiskers. The problems related to the growth of tin whiskers are stated, and the relevance of oxide layers adhering to whiskers is discussed.

Modern laboratory methods including focused ion beam sectioning, energy dispersive spectroscopy and X-ray photoelectron spectroscopy have been used to characterise the composition of oxides present on the surfaces of 48-year-old whiskers. These very old whiskers had nucleated and grown on electronic equipment stored at ambient temperatures. They were compared to the oxide layers on newly grown 2-week-old whiskers.

A dual oxide film, consisting of stannous and stannic oxides, was found present on both the old and the new whiskers. Measurements of oxide thickness were established for both generations of whiskers and these were noted to be similar to those films present on pure, cleaned bulk tin.

Only very new and very old whiskers, and their oxide films, were the focus of this investigation. However, sufficient data were gained to predict the effect both kinds of oxide films would have during whisker bridging between conductors and the risk of short circuits. Thick oxide films (order of 30 nm) may have a greater resistance to shorting, but they will be more difficult to remove during solder dipping (with respect to whisker mitigation).

A knowledge of the oxide thickness on growing/gyrating tin whiskers will provide the electronics industry with data useful for establishing the risk of short circuits. It will also be useful during the forensic work associated with component and assembly failure analysis.

The data resulting from this study are unique. They are of value to others who may require knowledge of the morphology, composition and thickness of oxides present on tin whiskers of different vintage.

Classical definitions of motivation typically involve two main components: direction and activation. Motivated behavior is directed toward or away from particular stimuli (i.e., appetitive and aversive motivation). Furthermore, activational aspects of motivation refer to the observation that motivated behavior is characterized by substantial activity, vigor, persistence, and exertion of effort in both the initiation and maintenance of behavior. Although separate neural systems direct organisms toward distinct motivational stimuli (e.g., food, water, sex), there appears to be a common circuitry regulating behavioral activation and the exertion of effort. Mesolimbic dopamine is one of the brain systems mediating activational aspects of motivation and exertion of effort. This system integrates aspects of motivation and motor control functions involved in the instigation of action. Research on the neurobiology of effort has contributed to our understanding of the pathophysiology of neurological and psychiatric disorders that are characterized by motivational dysfunction.

The purpose of this paper is to investigate the oxidation behaviour of an immersion tin final finish after multiple reflow ageing under air and nitrogen atmospheres and to study their influence on the wetting behaviour with lead‐free solder. To design a model that describes the degradation of wetting behaviour after reflow‐cycling of the immersion tin final finish.

A special printed circuit boards (PCB) demonstrator was created to investigate the immersion tin final finish with surface analysis methods and wetting tests. The PCB samples were aged by multiple reflow‐cycling under air and nitrogen atmospheres. The tin oxide formation behaviour of immersion tin was characterised using X‐ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM) and SERA analysis.

The native oxide layer of the investigated immersion tin final finishes was approximately 7 nm on average. The TEM and XPS investigations indicated an amorphous structure of SnO and SnO₂. The solder spread test showed significantly different results for PCBs in “as received” condition compared to those after one and two times reflow ageing under a nitrogen solder atmosphere. The analysis methods revealed a slight increase in the tin oxide layer thickness and small areas with semi‐crystalline structure. Reflow ageing under an ambient solder atmosphere induced considerably thicker oxide layers, which could be observed by a yellow discoloration of the surface.

Measures to improve the wetting behaviour can be derived from the described model (i.e. use of higher tin layer thickness or protective films to reduce the tin oxidation).

A functional model for the solderability process of lead‐free solder on immersion tin PCB final finishes was derived and verified. By this, interactions between the state of the final finish and the solder can be described and potential solderability failures can be predicted.

The purpose of the present research is to address the issue by conceptualizing artificial intelligence (AI) experience quality and its dimensions, and furthermore, to empirically test the relationships among AI experience quality, positive affective reactions, AI experience satisfaction and AI-seeking intention.

The data were collected from an AI community canteen in Shanghai. They were also analyzed using exploratory and confirmatory factor analyses (EFA and CFA) and structural equation modeling (SEM).

Four primary dimensions and 15 sub-dimensions of AI experience quality for community canteens were identified. The hypothesized paths between the higher-order constructs – AI experience quality, positive affective reactions, AI experience satisfaction and AI-seeking intention – were confirmed as well.

This is the first study to synthesize AI experience quality, positive affective reactions, AI experience satisfaction and AI-seeking intention in an AI restaurant setting.

In-game advertising continues to increase in importance for both industry and academia. However, game difficulty – an important, real-world factor – has received little attention as a specific game-related factor that might impact the effectiveness of in-game advertisements. This study aims to investigate the influence of game difficulty on players’ affective response and subsequent memory of in-game ads, which were presented as either gain- or loss-framed messages.

Three experiments were conducted. Study 1 and Study 3 implemented a 2 (difficulty: easy/difficult) × 2 (ad framing: gain/loss) design. Study 2 implemented a 2 (background music: calm/stressful) × 2 (ad framing: gain/loss) design. All experiments took place in a research laboratory in which participants consented to the study, completed a pre-test questionnaire, played a video game, completed a post-test questionnaire and were debriefed.

More difficult game play led to greater negative affective response. A different game-based attribute – background music – did not influence affective response. A significant interaction in Study 1 revealed that brand recognition increased as players in a more negative affective state were exposed to the loss-framed message. The results were explained to occur via the congruency effects that game difficulty exerts on players’ affective and cognitive states.

The studies are the first to incorporate both videogame difficulty and ad framing into one study, which two real-world factors that can influence advertising’s effectiveness. Theoretical and practical implications are discussed.

The purpose of this paper is threefold. First, this study seeks to provide a framework for, and endeavor to gain, an in‐depth understanding of the decision‐making process in relation to playing or not playing massively multiplayer online role‐playing games (MMORPGs) by using qualitative data from interviewing both players and non‐players. Second, it seeks to establish a better measure and model using an ethnographic decision tree model that describes the decision‐making process of internet users. Finally, for cross‐validity purposes, it aims to verify the model using quantitative data from face‐to‐face surveys of players/non‐players in an online gaming context.

A two‐phase mixed method is adopted here. During the first phase, the decision tree development phase, to capture the concerns of internet users who are facing the choice of playing MMORPGs or not, qualitative‐based procedures are used to identify decision factors and organize them into a decision tree for better understanding a research problem. In the second phase, the decision tree verification phase, to test the predictive capability of the composite model, a quantitative‐based survey instrument, which represents the decision criteria identified in the first phase, is adopted for data collection and analysis.

The results revealed that 14 criteria, formulated as a decision tree, were identified in the model‐building phase. In the model‐testing phase, 137 decision processes were successfully predicted and 17 predictive pathways led to a decision against the factual, giving a predictive rate of 89 per cent.

The study bridges the gap between the research in online games and in decision making. At the theoretical level, the decision tree model can provide a more comprehensive and in‐depth explanation of the online games‐playing phenomenon. In practice, marketers can easily become aware of the user considerations and identify exactly what needs to be done to fulfil users' criteria for playing MMORPGs. And, from a methodological standpoint, a mixed method can help researchers improve techniques used in study for building more predictive models.

The aim of this paper is to enhance the control performance of dexterous hands, enabling them to handle the high data flow from multiple sensors and to meet the deployment requirements of deep learning methods on dexterous hands.

A distributed control architecture was designed, comprising embedded motion control subsystems and a host control subsystem built on ROS. The design of embedded controller state machines and clock synchronization algorithms ensured the stable operation of the entire distributed control system.

Experiments demonstrate that the entire system can operate stably at 1KHz. Additionally, the host can accomplish learning-based estimates of contact position and force.

This distributed architecture provides foundational support for the large-scale application of machine learning algorithms on dexterous hands. Dexterity hands utilizing this architecture can be easily integrated with robotic arms.