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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).

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.

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.

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.

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.

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.

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.

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

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.

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.

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.

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

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.

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

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.

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.

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.

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.

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.