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Solder joint failure history has generally been assumed to follow a straight line when plotted as a lognormal or 2‐parameter Weibull distribution. Test results presented here show that a deviation from straight‐line behaviour occurs at low percentage failure probabilities. This indicates that solder joint failure history is more correctly characterised as a 3‐parameter Weibull distribution with a failure‐free period of life for true wearout failures. The solder joint failure distribution characteristic is also affected by applied strain. Lower strain, in addition to increasing median life, also improves the distribution such that the number of cycles‐to‐first‐failure is increased compared with the median cycles‐to‐failure. The ratio of cycles‐to‐first‐failure/median cycles‐to‐failure and apparent Weibull slope increases as strain decreases in a predictable manner. The effects of part elevation, part size, solder joint volume and shape, conformal coating, temperature differential, and alternative board materials are also presented with test data showing the effect of variation of these parameters.

Rigid‐flex printed wiring constructed in different multilayer configurations and with varying features is discussed. Materials used in rigid‐flex construction have widely varying properties which cause processing difficulties and thermal stress related problems which can be minimised by proper construction features. Examples of failure mechanisms due to improper construction or material usage are given. Design considerations which will avoid construction related defects are summarised.

Purpose – This chapter presents some innovative ways in which researchers can collect survey data on various types of violence against women.

Methodology/approach – The suggestions made here are drawn from over 30 years of national, international, and local survey research.

Findings – The methods described in this chapter minimize underreporting, produce theoretically relevant data, and have meaningful policy consequences.

Originality/value – The research techniques reviewed here have made many important contributions to the field and the data they uncovered have helped raise public awareness about one of the world’s most compelling social problems.