A methodology for realistic space launch risk estimation using information-fusion-based metric

In light of the significant changes being observed in the US space industry, in terms of the increase share of commercial launches, the development of inland spaceports, and the emergence of new vehicle designs and propulsion systems, there is need to reassess launch safety. In this paper, several issues related to space launch safety are reviewed, one in particular being the use, as the main the safety metric, of the mean collective risk to the general public, also known as the expectation of casualties. A new, decision level, information-fusion-based metric is proposed, and through a detailed case study, its merit in terms of the quality and quantity of information it generates is illustrated. The need for a new metric is here advocated as a critical first step toward the necessary transition from a risk avoidance philosophy to space launch safety to a risk management philosophy

A Framework To Model Complex Systems Via Distributed Simulation: A Case Study Of The Virtual Test Bed Simulation System Using the High Level Architecture

As the size, complexity, and functionality of systems we need to model and simulate con-tinue to increase, benefits such as interoperability and reusability enabled by distributed discrete-event simulation are becoming extremely important in many disciplines, not only military but also many engineering disciplines such as distributed manufacturing, supply chain management, and enterprise engineering, etc. In this dissertation we propose a distributed simulation framework for the development of modeling and the simulation of complex systems. The framework is based on the interoperability of a simulation system enabled by distributed simulation and the gateways which enable Com-mercial Off-the-Shelf (COTS) simulation packages to interconnect to the distributed simulation engine. In the case study of modeling Virtual Test Bed (VTB), the framework has been designed as a distributed simulation to facilitate the integrated execution of different simulations, (shuttle process model, Monte Carlo model, Delay and Scrub Model) each of which is addressing differ-ent mission components as well as other non-simulation applications (Weather Expert System and Virtual Range). Although these models were developed independently and at various times, the original purposes have been seamlessly integrated, and interact with each other through Run-time Infrastructure (RTI) to simulate shuttle launch related processes. This study found that with the framework the defining properties of complex systems - interaction and emergence are realized and that the software life cycle models (including the spiral model and prototyping) can be used as metaphors to manage the complexity of modeling and simulation of the system. The system of systems (a complex system is intrinsically a system of systems ) continuously evolves to accomplish its goals, during the evolution subsystems co-ordinate with one another and adapt with environmental factors such as policies, requirements, and objectives. In the case study we first demonstrate how the legacy models developed in COTS simulation languages/packages and non-simulation tools can be integrated to address a compli-cated system of systems. We then describe the techniques that can be used to display the state of remote federates in a local federate in the High Level Architecture (HLA) based distributed simulation using COTS simulation packages

Factors Affecting The Expectation Of Casualties In The Virtual Range Toxicity Model

The Virtual Range (VR) is an environment that integrates in a seamless fashion several models to improve complex systems visualization. A complex system is a non-linear system of systems whose interactions bring together interesting emergent properties that are very difficult to visualize and/or study by using the traditional approach of decomposition. The VR Toxicity Model as described here represents the different systems that interact in the determination of the expectation of casualties (Ec) resulting from the toxic effects of the gas dispersion that occurs after a disaster affecting a Space Shuttle within 120 seconds of liftoff. We present a detailed description of the VR and the factors affecting Ec. The system will help local authorities to estimate the population at risk in order to plan for areas to evacuate and/or for the resources required to provide aid and comfort and mitigate damages in case of a disaster

FACTORS AFFECTING THE EXPECTATION OF CASUALTIES IN THE VIRTUAL RANGE TOXICITY MODEL

The Virtual Range (VR) is an environment that integrates in a seamless fashion several models to improve complex systems visualization. A complex system is a non-linear system of systems whose interactions bring together interesting emergent properties that are very difficult to visualize and/or study by using the traditional approach of decomposition. The VR Toxicity Model as described here represents the different systems that interact in the determination of the expectation of casualties (Ec) resulting from the toxic effects of the gas dispersion that occurs after a disaster affecting a Space Shuttle within 120 seconds of liftoff. We present a detailed description of the VR and the factors affecting Ec. The system will help local authorities to estimate the population at risk in order to plan for areas to evacuate and/or for the resources required to provide aid and comfort and mitigate damages in case of a disaster