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Compared with a single platform, cooperative autonomous unmanned aerial vehicles (UAVs) offer efficiency and robustness in performing complex tasks. Focusing on ground mobile targets that intermittently emit radio frequency signals, this paper presents a decentralized control architecture for multiple UAVs, equipped only with rudimentary sensors, to search, detect, and locate targets over large areas. The proposed architecture has in its core a decision logic which governs the state of operation for each UAV based on sensor readings and communicated data. To support the findings, extensive simulation results are presented, focusing primarily on two success measures that the UAVs seek to minimize: overall time to search for a group of targets and the final target localization error achieved. The results of the simulations have provided support for hardware flight tests.

This paper describes how to use backstepping to develop control laws to perform trajectory tracking for a nonlinear, underactuated surface vessel. The research extends earlier backstepping designs for underactuated vessels by explaining how to select outputs when generalized forces act on the vessel. The resulting control law can correct orientation errors to track linear trajectories and can track arcs of circles with a fixed offset. The paper provides detailed derivations along with simulation results to illustrate the approach.

Compared with a single platform, cooperative autonomous unmanned aerial vehicles (UAVs) offer efficiency and robustness in performing complex tasks. Focusing on ground mobile targets that intermittently emit radio frequency signals, this paper presents a decentralized control architecture for multiple UAVs, equipped only with rudimentary sensors, to search, detect, and locate targets over large areas. The proposed architecture has in its core a decision logic which governs the state of operation for each UAV based on sensor readings and communicated data. To support the findings, extensive simulation results are presented, focusing primarily on two success measures that the UAVs seek to minimize: overall time to search for a group of targets and the final target localization error achieved. The results of the simulations have provided support for hardware flight tests.

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As medical students enter the role of physician, clinical outcomes not only rely on their mastery of clinical knowledge, but also on the effectiveness in which they can communicate with patients and family members. While students typically have numerous opportunities to practice clinical communication with adult patients, such practice in pediatric settings is limited. This study examines if simulated patient (SP) encounters strengthen third-year medical students’ communication skills during the pediatrics clerkship. During 2011-2013, three SP encounters (comprising 3 pediatric scenarios) were incorporated into a pediatrics clerkship at one United States medical school to give students a safe venue to practice advanced communication with observation and direct feedback. Third-year medical students engaged in the scenarios and received both written and oral feedback from an evaluator observing the encounter. With IRB approval, students’ self-perceived confidence and abilities at performing the advanced communication skills were measured using an eightitem, Likert scale questionnaire administered pre and post the SP encounter. Pre- and post-questionnaires (n=215; response rate, 96%) analyzed using a Wilcoxon-matched pairs signed-rank test demonstrated statistically significant increases in students’ perception of their confidence and abilities regarding their performance (P<0.05; Bonferroni correction, P<0.006). There was an increases in student confidence and self-perceived ability in: first, communicating with children and family members of young patients; second, managing confrontational situations involving parents; third, performing a thorough psychosocial history with an adolescent; and fourth, using Evidence Based Medicine to motivate parents.