Strategies for integrating models of interdependent subsystems of complex system-of-systems products

2006 Proceeding of the Thirty-Eighth Southeastern Symposium on System Theory© Copyright 2006 IEEEThe Office of Naval Research has established a need for improved design and analysis methods for the next generation of naval surface combatants. The Aerospace Systems Design Lab (ASDL) has initiated the Integrated Reconfigurable Intelligent Systems project to address design issues associated with the future systems. A goal of this program is to define preliminary approaches for developing an integrated modeling and simulation environment for complex systems. Since such systems are heterogeneous, dynamical and interdependent we suggest that a system-of-systems multidisciplinary approach is most appropriate for investigating and executing solutions. An integration methodology employing innovative techniques and a framework of tools that can be used to couple disparate models and simulations is presented. Methods for validating the final product to justify the selected approach and demonstrate a proof of concept for the integrated model are also discussed

A Feasibility Study for the Development of Air Mobility Operations within an Airport City (Aerotropolis)

Presented at the AIAA SciTech 2023 ForumThis study aims to create a simulation environment to study the feasibility of an Advanced Air Mobility (AAM) system in an airport-centric infrastructure or aerotropolis area. The environment and the study are to confirm the effectiveness of the AAM system in terms of reducing traffic congestion for road networks and the reduction in carbon emissions for transportation methods. The traffic simulation will run a baseline simulation with the currently available mobility methods and an alternative simulation with a proposed small network with close distance flights AAM system of 9 vertiports. The traffic modeling utilizes Agent-Based Modeling (ABM) to accurately models the two cases and compare trip times of the two cases. The emission modeling models the emission of carbon per mile of travel for different mobility methods and use the miles traveled from the traffic simulation to calculate the emission. The conclusion was drawn based on the two comparisons of the change in travel time and the change in emission. A small AAM system servicing a small area with short flight legs is found to be effective in both decreasing trip times and decreasing emissions and is significantly more effective when the ground mobility network is congested and not accessible

A Bibliometric Approach to Characterizing Technology Readiness Levels Using Machine Learning

Presented at the AIAA SCITECH 2023 Forum in National Harbor, Maryland.As cislunar space becomes more accessible to national space agencies and commercial entities, there is a constant need to improve the way in which space missions are planned, and development progress is tracked. A technologies stage of development, which is related to mission budget and schedule, is typically quantified using technology readiness levels (TRL). The process of determining TRL is often long and laborious, and requires the use of subject matter experts. As a part of the Georgia Institute of Technology Cislunar Architecture Initiative, this work serves to develop the early stages of an environmental scanning approach to maturity assessment that allows for the automatic determination of a technologies TRL using machine learning ordinal regression techniques with bibliometric factors. The bibliometric factors considered were: scientific publications, National Science Foundation awards, patents, and NASA Spinoff articles. Annual data on these factors was collected for 31 technologies between 1995-2015 using public APIs, and S-curves fit to the data to estimate each technologies point in the development cycle. The final model performed with an R² of 0.817, 0.812, and 0.567 on the training, validation, and test data, respectively. Additionally, a better performing model to classify a technologies technology life cycle phase was created and drawbacks to this approach discussed

A probabilistic technique for the assessment of complex dynamic system resilience

In the presence of operational uncertainty, one of the greatest challenges in systems engineering is to ensure system effectiveness, mission capability and survivability. Safety management is shifting from passive, reactive and diagnosis-based approaches to autonomous architectures that will manage safety and survivability through active, proactive and prognosis-based solutions. Resilience engineering is an emerging discipline, with alternative recommendations on safer and more survivable system architectures. A resilient system can "absorb" the impact of change due to unexpected disturbances, while it "adapts" to change, in order to maintain its physical integrity and mission capability. A framework of proposed resilience estimations is the basis for a scenario-based assessment technique, driven by modeling and simulation-based (M&S) analysis, for obtaining system performance, health monitoring, damage propagation and overall mission capability responses. For the technique development and testing, a small-scale canonical problem has been formulated, involving a reconfigurable spring-mass-damper system, in a multi-spring configuration. Operational uncertainty is introduced through disturbance factors, such as external forces with varying magnitude, input frequency, event duration and occurrence time. Case studies with varying levels of damping and alternative reconfiguration strategies return the effects of operational uncertainty on system performance, mission capability, and survivability, as well as on the "restore", "absorb", and "adapt" resilience capacities. The Topological Investigation for Resilient and Effective Systems, through Increased Architecture Survivability (TIRESIAS) technique is demonstrated for a reduced scale, reconfigurable naval cooling network application. With uncertainty effects modeled through network leak combinations, TIRESIAS provides insight on leak effects to survival times, mission capability degradations, and on resilience function capacities, for the baseline configuration. Comparative case studies were conducted for different architecture configurations, which have been generated for different total number of control valves and valve locations on the topology.PhDCommittee Chair: Mavris, Dimitri; Committee Member: Ferrese, Frank; Committee Member: German, Brian; Committee Member: Volovoi, Vitali; Committee Member: Weston, Nei