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Mutual trust is a key factor in human-human collaboration. Inspired by this social interaction, we analyze human-agent mutual trust in the collaboration of one human and (semi)autonomous multi-agent systems. In the thesis, we derive time-series human-agent mutual trust models based on results from human factors engineering. To avoid both over- trust and under-trust, we set up dynamic timing models for the multi-agent scheduling problem and develop necessary and sufficient conditions to test the schedulability of the human multi-agent collaborative task. Furthermore, we extend the collaboration between one human and multiple agents into the collaboration between multi-human network and swarm-based agents network. To measure the collaboration between these two networks, we propose a novel measurement, called fitness. By fitness, we can simplify multi-human and swarms collaboration into one-human and swarms collaboration. Cooperative control is incorporated into the swarm systems to enable several large-scale agent teams to simultaneously reach navigational goals and avoid collisions. Our simulation results show that the proposed algorithm can be applied to human- agent collaboration systems and guarantee effective real-time scheduling of collaboration systems while ensuring a proper level of human-agent mutual trust.

Designing secure cyber-physical systems (CPS) is fundamentally important. An indispensable step towards this end is to perform vulnerability assessment. This thesis discusses the design and implementation of a mission-aware CPS vulnerability assessment framework. The framework intends to accomplish three objectives including i) mapping CPS mission into infrastructural components, ii) evaluating global impact of each vulnerability, and iii) achieving verifiable results and high flexibility. In order to accomplish these objectives, a model-based analysis strategy is employed. Specifically, a CPS simulator is used to model dynamic behaviors of CPS components under different missions; the framework facilitates a bottom-up approach to traverse a holistic model of a CPS that aims at profiling relationships among all CPS components. In order to analyze the derived models, we have leveraged formal methods, including program symbolic execution, logic programming, and linear optimization. The framework first successfully identifies mission-critical components, then discovers all attack paths from system access points to mission-critical components, and finally recommends the optimized mitigation plan.

The Chattahoochee River begins in the Appalachian Mountains in northeast Georgia, flows through Atlanta, and then turns south to form the Georgia/Alabama state line. There are many dams along the river to help supply power, and many recreational areas. Most importantly, the Chattahoochee River provides 70% of metropolitan Atlanta’s drinking water. With all of these benefits, we should be protecting the river, but we are not. The water is polluted and gets more polluted the further south you go. In my photographs, I want to bring this to people’s attention. I used photographic negatives “damaged” in water to print my final photographs, hoping the resulting images would awaken viewers’ interest. I want to add my voice to that of other artists who work with water issues, such as Joe Cooks, Alex Kirkbride, and Yin Xiuzhen, and show how the shortage of clean water is not just a local problem for the city of Atlanta, but also a global problem.