Reliability prediction methodologies, especially those centered on Military Handbook (MIL-HDBK) 217 and its progeny are highly controversial in their application. The use of reliability predictions in the design and operation of military applications have been in existence since the 1950's. Various textbooks, articles, and workshops have provided insight on the pros and cons of these prediction methodologies. Recent research shows that these methods have produced highly inaccurate results when compared to actual test data for a number of military programs. These inaccuracies promote poor programmatic and design decisions, and often lead to reliability problems later in development. Major reasons for handbook prediction inaccuracies include but are not limited to: 1) The handbook database cannot keep pace with the rapid advances in the electronic industry. 2) Only a small portion of the overall system failure rate is addressed 3) Prediction methodologies rely soley on simple heuristics rather than considering sound engineering design principles. Rather than rely on inaccurate handbook methodologies, a reliability assessment methodology is recommended. The reliability assessment methodology includes utilizing reliability data from comparable systems, historical test data, and leveraging subject-matter-expert input. System developers then apply fault-tree analysis (or similar analyses) to identify weaknesses in the system design. The elements of the fault tree are assessed against well-defined criteria to determine where additional testing and design for reliability efforts are needed. This assessment methodology becomes a tool for reliability engineers, and ultimately program managers, to manage the risk of their reliability program early in the design phase when information is limted.

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How can domestic housing be adapted to support people living with dementia staying in their own homes for as long as they choose? This paper describes the innovative practice of using evidence-based design personas in a building refurbishment project (Chris and Sally's House) with a multidisciplinary team of architects, ergonomists, psychologists and experts. A 100 sqm Victorian two bedroom house was adapted to help educate house builders, carers and relatives on how to better support those living with dementia to live in their own home for longer. The design principles include clear sight lines, mobility support and provision for overnight carers.

The complex needs of people with dementia can create challenges when designing care environments. A Human Factors and Ergonomics (HFE) approach to the design of dementia care environments was used to address this challenge, and support wellbeing and independence for system users. Four individual personas (Alison, Barry, Christine and David) and a couple persona (Chris and Sally) were developed to represent the needs of people living with dementia. The aim was to facilitate the exchange of information and expertise between stakeholders and improve understanding of the characteristics of system users. An evidence-based approach involved extracting information from design, dementia, and clinical literature. This was followed by an iterative persona development process and a validation exercise to review the concept, content and applications. This paper outlines the development process, describes each persona and discusses current and potential applications.

Designing care environments for people living with dementia is a complex challenge as the key stakeholder may have difficulty communicating their capabilities, limitations and preferences. This paper describes the use of evidence-based design personas in a multidisciplinary team with architects and chartered human factors specialists. Four individual personas (Alison, Barry, Christine and David) and a couple persona (Chris and Sally) were used to bring the voices of the people living with different stages of dementia to the design process. Their changing/fluctuating symptoms were communicated in two formats (wheel and matrix) within an inclusive design process to adapt a Victorian semi-detached house. The demonstrator house presents evidencebased design, adaptation and support solutions to support people living with dementia to age well at home.