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Article
Publication date: 27 September 2011

Gilad Sharon and Donald Barker

The purpose of this paper is to evaluate modeling of the reliability characteristics of the copper (Cu) used in plated through holes (PTHs) for electrical connections…

Abstract

Purpose

The purpose of this paper is to evaluate modeling of the reliability characteristics of the copper (Cu) used in plated through holes (PTHs) for electrical connections across printed circuit boards (PCBs).

Design/methodology/approach

Assessments of the Cu damage in the first three reflow cycles are performed using finite element analysis. A two‐dimensional axi‐symmetric model of a PTH on a laminate board is validated against a three‐dimensional full model and test cases. Stress and strain measurements in the inner ring of the PTH are obtained in numerical simulations.

Findings

Loads applied after the reflow cycles contribute to subsequent mechanical disconnects. Reliability assessments relying on undamaged circuits are less accurate than estimates incorporating Cu damage following three reflow cycles.

Originality/value

In order to increase the accuracy of PCB reliability predictions significantly, prior‐to‐use damage should be calculated. In this paper, a modification to the reliability analysis is proposed.

Details

Multidiscipline Modeling in Materials and Structures, vol. 7 no. 3
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 24 May 2013

Gilad Sharon, Rachel Oberc and Donald Barker

The development of micro‐electro‐mechanical systems (MEMS) for use in military and consumer electronics necessitates an analysis of MEMS component reliability. The…

Abstract

Purpose

The development of micro‐electro‐mechanical systems (MEMS) for use in military and consumer electronics necessitates an analysis of MEMS component reliability. The understanding of the reliability characteristics of SCSi within MEMS structures should be improved to advance MEMS applications. Reliability assessments of MEMS technology may be used to conduct virtual qualification of these devices more efficiently. The purpose of this paper is to create a simple, inexpensive test methodology to use the dynamic fracture strength of a MEMS device to predict its reliability, and to verify this method through experimentation.

Design/methodology/approach

The dynamic fracture strength of single crystal silicon (SCSi) was used to model MEMS devices subjected to high shock loading. Experimentation with SCSi MEMS structures was performed following the proposed test methodology. A probabilistic distribution for bending of Deep Reactive Ion Etching (DRIE) processed SCSi around the <110> directions was generated as a tool for assessing product reliability.

Findings

Post shock test inspections revealed that failures occurred along {111} planes. Additional experiments provided preliminary estimates of the fracture strength for bending of DRIE processed SCSi around the <100> directions in excess of 1.1 GPa.

Originality/value

This paper proposes a test methodology for an efficient method to assess the reliability of processed SCSi based on dynamic fracture strength.

Details

International Journal of Structural Integrity, vol. 4 no. 2
Type: Research Article
ISSN: 1757-9864

Keywords

Content available
Article
Publication date: 1 October 2002

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Abstract

Details

Library Hi Tech News, vol. 19 no. 10
Type: Research Article
ISSN: 0741-9058

Article
Publication date: 13 April 2010

Mei-Ling Wu

The purpose of this paper is to identify the critical parameters that influence ball grid array and chip size package fatigue life in a random vibration environment by…

Abstract

Purpose

The purpose of this paper is to identify the critical parameters that influence ball grid array and chip size package fatigue life in a random vibration environment by using a design of experimental (DOE) approach using simulation results.

Design/methodology/approach

The use of DOE and analysis of variation to identify the critical parameters and a response surface to generate a functional form for global modeling would be determined. Once the global modeling’s functional form was known, it can be used as boundary condition, which would be input to a local model. Knowing the critical stress, one would estimate the fatigue life from a damage model. It is the curvature of the printed wiring board in the region of the component of interest that is driving the component’s solder joint damage. The approach in this present work involves global-local modeling approaches. In the global model approach, the vibration response of the printed circuit board (PCB) will be determined.

Findings

This global model will give the response of the PCB at specific component locations of interest. This response is then fed into a local stress analysis for accurate assessment of the critical stresses in the solder joints of interest. The stresses are then fed into a fatigue damage model to predict the life.

Originality/value

The analysis proposed in this paper uses a failure type approach to damage analysis and involves global and local model approaches.

Details

Soldering & Surface Mount Technology, vol. 22 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 1 February 1995

D.B. Harris and M.G. Pecht

This paper presents the methods and results of load, deflection and electrical contact resistance experiments for reliable electronic module design using fuzz button…

Abstract

This paper presents the methods and results of load, deflection and electrical contact resistance experiments for reliable electronic module design using fuzz button technology. Both beryllium copper (BeCu) and molybdenum (Mo) fuzz button contacts were examined, as a function of wire diameter, button diameter and button density.

Details

Circuit World, vol. 21 no. 2
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 1 June 1988

C. John Langley, David P. Carlisle, Stephen B. Probst, Donald F. Biggs and Roy E. Cail

Study teams, including industry representatives, themselves experienced in the use of microcomputers in logistics, report on a survey of such use.

Abstract

Study teams, including industry representatives, themselves experienced in the use of microcomputers in logistics, report on a survey of such use.

Details

International Journal of Physical Distribution & Materials Management, vol. 18 no. 6
Type: Research Article
ISSN: 0269-8218

Article
Publication date: 23 October 2007

Fiona Rowe, Donald Stewart and Carla Patterson

The purpose of this paper is to develop a framework to demonstrate the contribution of whole school approaches embodied by the health‐promoting school approach, to the…

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Abstract

Purpose

The purpose of this paper is to develop a framework to demonstrate the contribution of whole school approaches embodied by the health‐promoting school approach, to the promotion of school connectedness, defined as the cohesiveness between diverse groups in the school community, including students, families, school staff and the wider community.

Design/methodology/approach

A cross‐disciplinary review of literature was conducted to identify strategies consistent with the health‐promoting school approach and the values and principles that promote school connectedness. The review included peer‐reviewed articles and published books and reports identified from the databases spanning the education, health, social science and science disciplines and used search terms encompassing health and mental health promotion, schools, social connectedness, belonging and attachment. The paper is also a framework of the contribution of the health‐promoting school approach to promoting school connectedness and was developed drawing on health promotion strategies at the broader community level known to foster connectedness.

Findings

The paper found that the framework developed illustrates how the health‐promoting school approach has the potential to build school connectedness through two major mechanisms: inclusive processes that involve the diversity of members that make up a community; the active participation of community members and equal “power” relationships, or equal partnerships among community members; and supportive structures such as school policies, the way the school is organised and its physical environment, that reflect the values of participation, democracy and inclusiveness and/or that promote processes based on these values.

Practical implications

In this paper the detailed mechanisms outlined in the framework provide practical strategies for health promotion practitioners and educators to use in the everyday school setting to promote school connectedness.

Originality/value

This paper draws together substantial bodies of evidence and makes a persuasive case for the contribution of the health‐promoting school approach to building school connectedness.

Details

Health Education, vol. 107 no. 6
Type: Research Article
ISSN: 0965-4283

Keywords

Article
Publication date: 15 February 2016

Shahed Imam and Crawford Spence

The purpose of this paper is to shed light on the nature of the work that financial analysts actually do in the context of the market for information and to further open…

3000

Abstract

Purpose

The purpose of this paper is to shed light on the nature of the work that financial analysts actually do in the context of the market for information and to further open up research in this area to qualitative and sociological inquiry.

Design/methodology/approach

A field study with 49 financial analysts (both buy-side and sell-side) was undertaken in order to understand the work that they actually do. This field study was theoretically informed by the sociology of Pierre Bourdieu.

Findings

The authors find, in contrast to both conventional wisdom and assumptions in prior (mostly quantitative) literature, that the primary value of sell-side analyst work lies not in the recommendations that analysts ultimately produce, but in the rich contextual information that they provide to buy-side analysts. In order to successfully provide this information, analysts have to embody large amounts of technical capital into their habitus.

Research limitations/implications

Much research in this area erroneously presumes that forecasting is the primary function of analysts. Analyst work needs to be understood as multifarious and requiring a well-developed habitus that is attuned to the accumulation of both technical and social capital. Future qualitative research might usefully explore in more detail the way in which corporate managers interact with analysts. The present study solicits the viewpoints only of the analysts themselves. The organisational context of the analysts was not explored in detail and the interviews were pre-crisis, which possibly explains why the technical capital of sell-side analysts was extolled by interviewees rather than lambasted.

Originality/value

The paper is one of few studies to look at analysts from a qualitative and sociological perspective. It both complements and extends both emerging sociological work on financial intermediaries and qualitative work on the “market for information”.

Details

Accounting, Auditing & Accountability Journal, vol. 29 no. 2
Type: Research Article
ISSN: 0951-3574

Keywords

Book part
Publication date: 21 December 2006

Jumpei Ichinosawa

Economic anthropology of bazaar-type markets for material goods has developed a model of markets under uncertain conditions through microscopic analyses of seller–buyer…

Abstract

Economic anthropology of bazaar-type markets for material goods has developed a model of markets under uncertain conditions through microscopic analyses of seller–buyer relationships. The model implies that serious lack of information makes the individuals highly risk-averse and leads to long-term, balanced clientelization. Presented in this chapter is another model of uncertain market conditions. In a bazaar-type market of interpersonal service the individuals are likely to be both chance-seekers as well as risk-averters. Such an attitude derives from a combination of unique service characteristics and uncertain market conditions. Transactions of commodified sexual services (termed here “interpersonally embedded services”) among chance-seekers in bangkok go-go bars often result in disequilibration, rather than equilibration, of the seller–buyer relationship.

Details

Choice in Economic Contexts
Type: Book
ISBN: 978-0-76231-375-4

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