The objective of this work was to assess the functional utility of new display concepts for an emergency department information system created using cognitive systems engineering methods, by comparing them to similar displays currently in use. The display concepts were compared to standard displays in a clinical simulation study during which nurse-physician teams performed simulated emergency department tasks. Questionnaires were used to assess the cognitive support provided by the displays, participants' level of situation awareness, and participants' workload during the simulated tasks. Participants rated the new displays significantly higher than the control displays in terms of cognitive support. There was no significant difference in workload scores between the display conditions. There was no main effect of display type on situation awareness, but there was a significant interaction; participants using the new displays showed improved situation awareness from the middle to the end of the session. This study demonstrates that cognitive systems engineering methods can be used to create innovative displays that better support emergency medicine tasks, without increasing workload, compared to more standard displays. These methods provide a means to develop emergency department information systems-and more broadly, health information technology-that better support the cognitive needs of healthcare providers.

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Often network users are not perfectly rational, especially when they are satisficing-rather than optimizingdecision makers and each individual's perception of the decision environment reflects personal preferences or perception errors due to lack of information. While the assumption of satisficing drivers has been used in modeling route choice behavior, this research uses a link-based perception error model to describe driver's uncertain behavior, without assuming stochasticity. In congestion-free networks, we show that the perception error model is more general than the existing bounded rationality models with satisficing drivers with special cases when the two approaches yield the same results; that is, satisficing under accurate perception is equivalent to optimizing under inaccurate perception. This motivates us to define generalized bounded rationality in route choice behavior modeling. The proposed modeling framework is general enough to capture link-specific cost-perception of drivers. We use a Monte Carlo method to estimate modeling parameter values to guarantee a certain coverage probability in comparison with the random utility model. We demonstrate how the notion of generalized bounded rationality can be used in robust multi-commodity network design problems and devise a cutting plane algorithm. We illustrate our approaches in the context of hazardous materials transportation.

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The mechanisms that underlie fascinating inter-individual interactions among animal groups have attracted increasing attention from biologists, physicists, and system scientists. There are two well-known types of interaction patterns: hierarchical and egalitarian. In the former type, individuals follow their leaders, whereas they follow their neighbors in the latter. Using high-resolution spatiotemporal data derived from the free flights of a flock of pigeons, we show that pigeon flocks actually adopt a mode that switches between the two aforementioned strategies. To determine its flight direction, each pigeon tends to follow the average of its neighbors while moving along a smooth trajectory, whereas it switches to follow its leaders when sudden turns or zigzags occur. By contrast, when deciding how fast to fly, each pigeon synthesizes the average velocity of its neighbors. This switching mechanism is promising for possible industrial applications in multi-robot system coordination, unmanned vehicle formation control, and other areas.