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    An ‘Ethical Black Box’, Learning From Disagreement in Shared Control Systems

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    Shared control, where a human user cooperates with an algorithm to operate a device, has the potential to greatly expand access to powered mobility, but also raises unique ethical challenges. A shared-control wheelchair may perform actions that do not reflect its user’s intent in order to protect their safety, causing frustration or distrust in the process. Unlike physical accidents there is currently no framework for investigating or adjudicating these events, leading to a reduced capability to improve the shared control algorithm’s user experience. In this paper we suggest a system based on the idea of an ‘ethical black box’ that records the sensor context of sub-critical disagreements and collision risks in order to allow human investigators to examine them in retrospect and assess whether the algorithm has taken control from the user without justification

    Smart battery pack for electric vehicles based on active balancing with wireless communication feedback

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    In this paper, the concept of smart battery pack is introduced. The smart battery pack is based on wireless feedback from individual battery cells and is capable to be applied to electric vehicle applications. The proposed solution increases the usable capacity and prolongs the life cycle of the batteries by directly integrating the battery management system in the battery pack. The battery cells are connected through half-bridge chopper circuits, which allow either the insertion or the bypass of a single cell depending on the current states of charge. This consequently leads to the balancing of the whole pack during both the typical charging and discharging time of an electric vehicle and enables the fault-tolerant operation of the pack. A wireless feedback for implementing the balancing method is proposed. This solution reduces the need for cabling and simplifies the assembling of the battery pack, making also possible a direct off-board diagnosis. The paper validates the proposed smart battery pack and the wireless feedback through simulations and experimental results by adopting a battery cell emulator

    Unstable fingering patterns of Hele-Shaw flows as a dispersionless limit of the KdV hierarchy

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    We show that unstable fingering patterns of two dimensional flows of viscous fluids with open boundary are described by a dispersionless limit of the KdV hierarchy. In this framework, the fingering instability is linked to a known instability leading to regularized shock solutions for nonlinear waves, in dispersive media. The integrable structure of the flow suggests a dispersive regularization of the finite-time singularities.Comment: Published versio

    Impact of an external electron acceptor on phosphorus mobility between water and sediments

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    The present work assessed the impact of an external electron acceptor on phosphorus fluxes between water-sediment interface. Microcosm experiments simulating a sediment microbial fuel cell (SMFC) were carried out and phosphorus was extracted by an optimized combination of three methods. Despite the low voltage recorded, ∼96 mV (SMFC with carbon paper anode) and ∼146 mV (SMFC with stainless steel scourer anode), corresponding to a power density of 1.15 mW/m2 and 0.13 mW/m2, it was enough to produce an increase in the amounts of metal bound phosphorus (14% vs 11%), Ca-bound phosphorus (26% vs 23%) and refractory phosphorus (33% vs 28%). These results indicate an important role of electroactive bacteria in the phosphorus cycling and open a new perspective for preventing metal bound phosphorus dissolution from sediments.The authors are indebted and grateful to the Regional Department of Water Resources and Land Planning (Azores) and its staff. The authors also acknowledge the Grant SFRH/BPD/8052812011 from the Foundation for Science and Technology, Portugal, awarded to Gilberto Martins
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