This paper states our position regarding the desirable properties of a discrete simulation environment and details our response to this. Following a brief introductory examination of the pre-existing art in microsimulation modelling, we describe our approach and detail its structure and use.

In this paper we present an approach to the modelling of human interaction in complex environments and its application to a security related scenario; the evacuation of a railway station subsequent to the detonation of an improvised explosive device.The intent of the experiments reported in this paper is to investigate the application of our existing software capabilities to the proof-of-concept scenario described above.Our simulation framework, Simulacron, allows the development of multiple interacting modules which address matters such as motivation, scheduling and movement, controlled both by internal goals and external influences. The ability to integrate this interaction modelling with our existing, rich palette of capabilities makes this approach to simulation building of particular interest.In this paper, we pay particular attention to the motivation module, which allows the coupling of internal characteristics with external conditions to control behaviour.Sydney's Central Station is represented in this scenario with a directed graph of some 200 locations. Through this, five thousand commuters move over the course of two simulated hours at a temporal granularity of 5 seconds. Typical run time was on the order of one hour on a consumer desktop using a single thread.Commuter behaviours, which have been selected based on actual, observed behaviours in similar circumstances, are represented by a number of states, driven by transition rules using a set of hypothetical characteristics.We report the results of several variations to the base scenario where we modify commuter and assailant characteristics. Additionally, we report on a set of simulations in which simple crowd management strategies are implemented to investigate their potential impact on the evacuation process.We conclude that the results broadly agree with expected behaviours and justify further development. This would include the incorporation of psychologically-grounded characteristics and the extension of the work to a full validation scenario.We foreshadow a range of future initiatives including a study to determine the interaction between evasion resulting from perceived assailant threat and fatality rates.The work to date has provided us with a simulation environment into which we can now introduce more experimentally derived parameter values, covering not only internal states but also allowing the introduction of passenger schedules and the incorporation of incoming and outgoing trains. The incorporation of additional features, such as: more realistic evasion, security force interdiction, multiple assailants including decoys, caring for the injured, families, biological imperatives, such as hunger, and disorientation during evacuations, is planned for the future.

In this paper, we present an extension of our novel microsimulation technique, as applied to biological infection spread, to estimate the underlying causal parameters driving an infectious process. The underlying simulation framework, Simulacron, was developed in order to understand the development and course of, response to and recovery from single and multiple threats on community populations. Such threats include a range of natural (such as disease spread in communities, fire, flood etc.) and manmade events (such as terrorism, including the use of biological agents, money laundering, smuggling as well as accidents etc.). These threats can cause serious disruption to modern society and the optimal approaches to prevention, mitigation, response and recovery are little understood. Furthermore, assumptions currently used cannot otherwise be readily tested.

This paper examines the effect of varying attack and interdiction strategies, both alone and in combination, in an urban transport hub. Particular attention is paid to the potential disruption to normal commuter services resulting from an intrusive stop and search regime.The work presented here represents a qualitative investigation in that many parameters relating to the details of the interdiction mechanisms are first-order approximations. However, the background against which the investigation is conducted has been constructed to be as realistic as possible.

The confrontation in Syria during 2013 is an ongoing cause for concern regarding the potential use of chemical and biological weapons. There have been reports of the use of chemical weapons including Sarin (BBC, 2013a) which UN chemical weapons inspectors are investigating (BBC, 2013b). If chemical weapons have been used by either side, then the potential use of biological weapons cannot be disregarded. In addition to stockpiles of chemical weapon (BBC 2013c), Syria is thought to have stockpiles of a number of biological agents including anthrax, plague, tularaemia, botulinium, smallpox and cholera (Gordon, 2007). Some groups sympathetic to Al Qaeda might also have access to some of these through their terrorist networks. Because these weapons can have a substantial impact beyond the immediate conflict zone, there are serious questions about how best to respond efficiently to their use and manage their impacts.One such concern is whether the response to an attack involving a single agent would be the same as when more than one agent is used. There are indications that infectious diseases which promote cytokine response can have a protecting effect on infection with a second disease (Graham et al., 2007, Barton et al, 2007. Plague affects the innate immune system by suppressing cytokine responses (Li et al., 2008) while smallpox activates the cytokine response (Fenner et al, 1988). Such an interaction is therefore possible with smallpox and plague in people who are infected with both diseases. While there are a number of papers on the management of both smallpox and plague (Halloran, (2002), Rani et al, (2004)), there are few, if any, which discuss infection by both agents simultaneously or the likely confounding factors that will affect outcomes in their infection control after the attack. In this paper we explore the application of microsimulation modelling of a simultaneous attack on a civilian population using plague and smallpox as an example of a simultaneous coinfection through its effect on the spread of disease and number of deaths As a basis for analysis, we have developed simulations involving a population of 1250 people based on NSW statistics for households and work. The structure of a community model of social mixing is briefly discussed, over which a multi-infection model is imposed that accounts for varying infectivity in different stages of each disease as well as confinement to home as each disease progresses. A number of simulations were run assuming 10% immunity to both diseases, to establish a baseline for each disease in the community. Further simulations were used to model the delay of the introduction of plague compared to smallpox between 0 and 35 days respectively. The strength of the immunological interaction by smallpox on plague deaths was also investigated. Each scenario was repeated 10 times to assess the variability.Our model showed the outcome is complex as the number of deaths is dependent on the delay in the release of plague and varies according to the number of people progressi...