Search results

1 – 10 of 193
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 1 December 2005

Junling Chang, Dirk Janz, W. Kempe and Xiaoming Xie

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…

591

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Soldering & Surface Mount Technology, vol. 17 no. 4
Type: Research Article
ISSN: 0954-0911

Keywords

Access Restricted. View access options
Article
Publication date: 1 December 2003

Cheng Bo, Wang Li, Zhang Qun, Gao Xia, Xie Xiaoming and Wolfgang Kempe

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…

327

Abstract

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.

Details

Soldering & Surface Mount Technology, vol. 15 no. 3
Type: Research Article
ISSN: 0954-0911

Keywords

Access Restricted. View access options
Article
Publication date: 1 September 2000

Saroja Subrahmanyan

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…

5713

Abstract

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.

Details

Journal of Product & Brand Management, vol. 9 no. 5
Type: Research Article
ISSN: 1061-0421

Keywords

Access Restricted. View access options
Article
Publication date: 1 December 2003

Cheng Bo, Wang Li, Zhang Qun, Gao Xia, Xie Xiaoming and Wolfgang Kempe

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…

350

Abstract

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.

Details

Soldering & Surface Mount Technology, vol. 15 no. 3
Type: Research Article
ISSN: 0954-0911

Keywords

Access Restricted. View access options
Article
Publication date: 23 January 2025

Olivia Aubrey, Katy A. Jones and Elizabeth Paddock

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…

14

Abstract

Purpose

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.

Design/methodology/approach

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).

Findings

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.

Originality/value

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.

Details

Journal of Criminal Psychology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2009-3829

Keywords

Access Restricted. View access options
Book part
Publication date: 7 July 2015

Olof Brunninge and Anders Melander

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…

Abstract

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.

Details

New Ways of Studying Emotions in Organizations
Type: Book
ISBN: 978-1-78560-220-7

Keywords

Access Restricted. View access options
Article
Publication date: 1 December 2001

G. Kaltenpoth, W. Siebert, X‐M. Xie and F. Stubhan

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…

360

Abstract

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.

Details

Soldering & Surface Mount Technology, vol. 13 no. 3
Type: Research Article
ISSN: 0954-0911

Keywords

Access Restricted. View access options
Article
Publication date: 11 February 2025

Kayla Alaniz, William R. King, Joseph Schafer, William Wells and John Jarvis

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…

8

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Research limitations/implications

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.

Originality/value

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.

Details

Policing: An International Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1363-951X

Keywords

Access Restricted. View access options
Article
Publication date: 1 January 1982

Connie Moraff

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…

301

Abstract

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.

Details

Collection Building, vol. 4 no. 1
Type: Research Article
ISSN: 0160-4953

Access Restricted. View access options
Book part
Publication date: 18 July 2016

Christopher J. Quinn, Matthew J. Quinn, Alan D. Olinsky and John T. Quinn

Online social networks are increasingly important venues for businesses to promote their products and image. However, information propagation in online social networks is…

Abstract

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.

Details

Advances in Business and Management Forecasting
Type: Book
ISBN: 978-1-78635-534-8

Keywords

1 – 10 of 193
Per page
102050