Reverse mathematics of first-order theories with finitely many models

We examine the reverse-mathematical strength of several theorems in classical and effective model theory concerning first-order theories and their number of models. We prove that, among these, most are equivalent to one of the familiar systems RCA(0), WKL0, or ACA(0). We are led to a purely model-theoretic statement that implies WKL0 but refutes ACA(0) over RCA(0)

Mapping the elements of physical security towards the creation of a holistic physical security model

This study has designed a theoretical mapping of complex element relationships within the field of physical security. The main purpose of the mapping is to form individual knowledge structures for modelling and provide a relative understanding of overall risk based on different combinations of physical security arrangements. An understanding of overall risk for modelling purposes should lead to improvements in providing support for decision making within this field. The final series of knowledge structures in this study have been represented by value matrices for element pair assessments within the topic of physical security. The values that have been presented in the knowledge matrices have been gathered from expert opinion and converted to numerical data as a demonstration for a holistic approach to modelling physical security elements. A profile for each respondent and each category group has been developed to be compared for their degree of similarity with other profiles. A correlation technique provides an indication of the degree of consensus within the results

Safety and Reliability - Safe Societies in a Changing World

The contributions cover a wide range of methodologies and application areas for safety and reliability that contribute to safe societies in a changing world. These methodologies and applications include: - foundations of risk and reliability assessment and management - mathematical methods in reliability and safety - risk assessment - risk management - system reliability - uncertainty analysis - digitalization and big data - prognostics and system health management - occupational safety - accident and incident modeling - maintenance modeling and applications - simulation for safety and reliability analysis - dynamic risk and barrier management - organizational factors and safety culture - human factors and human reliability - resilience engineering - structural reliability - natural hazards - security - economic analysis in risk managemen