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To investigate the degradation of lead free solder heat‐sink attachment by thermal shock. Samples with high voiding percentages were selected for the investigation in order to get information on the significance of voids on the reliability of Sn‐Ag‐Cu heat‐sink attachment.

Through the use of X‐ray, C‐mode scanning acoustic microscopy, dye penetration, cross section and scanning electron microscopy/energy‐dispersive X‐ray tests, the degradation of Sn‐Ag‐Cu heat‐sink attachment during thermal shock cycling was evaluated.

The results showed that the Sn‐Ag‐Cu heat‐sink attachment where the area of voiding was 33‐48 per cent survived 3,000 thermal shock cycles, although degraded. The main degradation mechanism for the solder attachment was not solder fatigue but interface delamination due to Kirkendall voids at the Cu/Cu₃Sn interface. It was found that the large voids in the Sn‐Ag‐Cu heat‐sink attachment were not significantly affecting the solder joint lifetime. Big differences of intermetallic compound growth behaviour and Kirkendall voids at device/solder and solder/Cu pad interfaces are found and the reasons for this are discussed.

This work has clarified the general perception that large voids affect the thermo‐mechanical lifetime of solder joint substantially and also provides further understanding of the Sn‐Ag‐Cu heat‐sink attachment degradation mechanism.

Flip chip solder joint reliability under thermal shock stress was investigated both experimentally and by 2D finite element simulation. The results indicate that solder fatigue is the dominant failure mode and that delamination has obvious adverse effects on the solder joint lifetime. Different material/process combinations (underfill, flux, reflow atmospheres) were designed in order to understand the role of material/process factors on the solder joint lifetime and the results are discussed.

Products that have a short selling season face high uncertainty in demand. Retailers who sell such products therefore find the task of pricing and inventory challenging. Many retailers consider making these decisions as an art form and do not use quantitative models that are developed by researchers. Describes how retailers typically make pricing and inventory decisions and also reviews quantitative models that have been developed by researchers to improve on one or more of these decisions. A classification of these models is developed and how they can assist the retailer is explained. A simple explanation of two mathematical tools, Bayesian updating of information and dynamic programming, which are commonly mentioned in the literature are also given.

Flip chip on board (FCOB) solder joint reliability under thermal shock stress was investigated. With underfill materials, the solder joint lifetime was increased from 37 to 1,300/2,480 cycles depending on the particular underfill material used. Through the use of CSAM, SEM, dye penetration tests and cross sectioning, the reliability of a FCOB assembly under thermal shock stress was evaluated. Both dye penetration and SEM fracture analysis can be used to measure quantitatively the extent of crack propagation for assemblies without underfill. A new failure mechanism, PCB cracking was also observed and discussed.

The societal, economic and personal costs of aggression are indisputable. Impulsivity and childhood trauma (CT) play a role in aggression but less is known about the potential mechanisms underlying these associations. This study aimed to investigate the influence of CTs and impulsivity on aggression in the general population.

A total of 178 participants (aged 18–86, M = 30.93, SD = 14.50) including 65 men (36.5%), 110 women (61.8%), 3 participants self-identified (1.7%)(n = 2 nonbinary, n = 1 gender fluid) of the UK adult population completed an online survey. Questionnaires measured impulsivity (Short UPPS-P), adverse childhood experiences (CT Questionnaire) and aggression (Buss and Perry Aggression Questionnaire).

Emotional neglect and abuse were the most endorsed CTs (abuse and neglect). As predicted, results showed the impulsivity facet “negative urgency” was associated with the behaviour, emotions and cognitions of aggression. Findings showed a distinct effect of both impulsivity and emotional abuse on physical aggression, which may reflect a pathway in which impulsivity influences adverse childhood experiences and future violence. Types of aggression may have potentially distinct pathways. This study discusses the reasons for these observed results and future research.

The originality/value of the paper lies in the acknowledgement of the role of negative and positive urgency in behaviours related to emotional dysregulation. It also highlighted the importance of examining different types of aggression. There was a distinct effect of both impulsivity and CTs on physical aggression and hostility. Further research in larger samples should examine pathways in which impulsivity mediates the effects of adverse childhood experiences and adulthood aggression. These collective insights can help further our understanding of the role adverse and traumatic events in childhood and impulsivity has on aggression and may be relevant to tailored support and intervention strategies for individuals expressing aggressive behaviours.

In this chapter, we explore the impact of socioemotional and financial wealth on the resource management of family firms. We use MoDo, a Swedish pulp and paper firm, covering three generations of owner-managers from 1873 to 1991, to grasp the shifting emphases on socioemotional and financial wealth in the management of the company. Identifying four strategic issues of decisive importance for the development of MoDo, we analyze the organizational values that guided the management of these issues. We propose that financial and socioemotional wealth stand for two different rationalities that infuse organizational values. The MoDo case illustrates how these rationalities go hand in hand for extended periods of time, safeguarding both financial success and socioemotional endowments. However, in a situation where the rationalities are no longer in line with the development of the industry context, the conflict arising between the two rationalities may have fatal consequences for the firm in question.

Flip chip test boards with and without plasma enhanced chemical vapor deposition silicon nitride moisture barrier coatings were exposed to high humidity and temperature cycling conditions. The effect of the stress developed in these environments was investigated and evaluated. The influence of the barrier layers on the extent of underfill delamination and degradation in flip chip assemblies was inspected by C‐mode Scanning Acoustic Microscopy. The moisture barrier layers studied show their potential to enhance the reliability of flip chip assemblies in humid environments.

The purpose of this paper was to examine how mid- and upper-level police commanders' occupational perceptions shifted after the COVID-19 pandemic, upsurge in police protests, and perceived crime increases in 2020. We assess the extent to which these events altered police leaders' perceptions of stress, satisfaction, burnout and turnover intentions.

This study employs repeated cross-sectional survey data of over 900 police leaders who attended the FBI’s National Academy (FBINA) program. Respondents are distinguished by whether they attended the FBINA program before or after operations were suspended due to COVID-19. Bivariate tests were conducted to compare pre- and post-respondents' perceptions of stress, satisfaction, burnout and turnover intentions.

The findings indicate that post-pandemic respondents had higher turnover intentions than pre-pandemic respondents. The groups had no significant differences regarding stress, satisfaction and burnout perceptions.

The findings suggest that despite facing a global pandemic, police protests and perceived increases in crime, police leaders demonstrated high stability and resiliency. The data comprised law enforcement leaders who participated in the FBINA program; thus, the findings may not be generalizable to all officers.

This study is one of the first to assess changes in police leaders’ work perceptions following the COVID-19 pandemic, the rise in police protests and perceived increases in crime in 2020.

The newly emerging field of family violence has its modern origins in the early 1960s with the publication in 1962 of an article by C. Henry Kempe entitled “The Battered Child Syndrome.” This article captured the attention of professionals in medicine and the social sciences. Since that time there have been numerous articles and books dealing with the causes, treatment, and prevention of child abuse. Kempe has continued to work on child abuse and is Director of the National Center for the Prevention and Treatment of Child Abuse and Neglect in Denver. In editing books on helping the child and the family, he has collaborated with Ray E. Heifer, Professor in Pediatrics and Human Development at Michigan State University.

Online social networks are increasingly important venues for businesses to promote their products and image. However, information propagation in online social networks is significantly more complicated compared to traditional transmission media such as newspaper, radio, and television. In this chapter, we will discuss research on modeling and forecasting diffusion of virally marketed content in social networks. Important aspects include the content and its presentation, the network topology, and transmission dynamics. Theoretical models, algorithms, and case studies of viral marketing will be explored.