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Epoxy resin emulsions are used in water‐based coatings for surface protection of concrete and metal. An unfortunate drawback for most emulsions is their poor freeze‐thaw stability. Epoxy emulsions are indeed unstable below 0°C, ‐5°C or ‐10°C, depending on the type of resin. In this study, other factors capable of influencing the freeze‐thaw behaviour were investigated: e.g. solids content, amount and type of emulsifiers, solvents, protective colloids. Discusses methods for testing the quality of thawed emulsions as well as the physics involved in their destabilization. Freeze‐thaw performance can be improved by different means but mostly not without sacrificing resistance properties of the coating. Therefore, avoiding temperatures below 0°C is still the best advice.

This paper aims to present a tool-supported approach for visualising personas as social goal models, which can subsequently be used to identify security tensions.

The authors devised an approach to partially automate the construction of social goal models from personas. The authors provide two examples of how this approach can identify previously hidden implicit vulnerabilities and validate ethical hazards faced by penetration testers and their safeguards.

Visualising personas as goal models makes it easier for stakeholders to see implications of their goals being satisfied or denied and designers to incorporate the creation and analysis of such models into the broader requirements engineering (RE) tool-chain.

The approach can be used with minimal changes to existing user experience and goal modelling approaches and security RE tools.

This research was founded on the premise that more can be done to help improve safety in the global construction industry. Worker fatigue-impairment may be an underlying cause or major contributor to accidents. Fatigue-impairment is believed to be pervasive in construction, and research has shown it can be as concerning as alcohol-impairment. When fatigue-impairment is acknowledged as existing, there is poor understanding of its severity or how it contributes to performance and accidents. The purpose of this research was to attempt to measure fatigue-impairment in real time.

This research expanded on actual measurements of fatigue-related impairment from workers on a large construction project displaying significant fatigue-related impairment. The research identified and tested possible techniques for real-time measurement solutions to assist with this safety-related issue. 100 participants had their sleep/wake cycles monitored for a month with an actigraph to derive their on-going mental effectiveness levels by the minute. The same participants took cognitive tests over the month to compare mental performance results to the modelled mental effectiveness levels.

Performance results from cognitive tests were compared with modelled mental effectiveness from actigraph-monitored sleep of 100 participants for a month each and showed significant correlation for all cognitive tests used.

This research showed that real-time surrogate measurements for fatigue-impairment in the workplace exist to assist organizations manage an important workplace hazard.

Derived from operational settings, this research developed predictive models based on simple, quick and inexpensive cognitive tests as screening techniques for workplace impairment and confirmed the need for and found a solution for fatigue monitoring in the workplace.