27 research outputs found

    Probabilistic Modeling of Space Shuttle Debris Impact

    Get PDF
    On Feb 1, 2003, the Shuttle Columbia was lost during its return to Earth. As a result of the conclusion that debris impact caused the damage to the left wing of the Columbia Space Shuttle Vehicle (SSV) during ascent, the Columbia Accident Investigation Board recommended that an assessment be performed of the debris environment experienced by the SSV during ascent. A flight rationale based on probabilistic assessment is used for the SSV return-to-flight. The assessment entails identifying all potential debris sources, their probable geometric and aerodynamic characteristics, and their potential for impacting and damaging critical Shuttle components. A probabilistic analysis tool, based on the SwRI-developed NESSUS probabilistic analysis software, predicts the probability of impact and damage to the space shuttle wing leading edge and thermal protection system components. Among other parameters, the likelihood of unacceptable damage depends on the time of release (Mach number of the orbiter) and the divot mass as well as the impact velocity and impact angle. A typical result is visualized in the figures below. Probability of impact and damage, as well as the sensitivities thereof with respect to the distribution assumptions, can be computed and visualized at each point on the orbiter or summarized per wing panel or tile zone

    Artificial Cognition for Social Human-Robot Interaction: An Implementation

    Get PDF
    © 2017 The Authors Human–Robot Interaction challenges Artificial Intelligence in many regards: dynamic, partially unknown environments that were not originally designed for robots; a broad variety of situations with rich semantics to understand and interpret; physical interactions with humans that requires fine, low-latency yet socially acceptable control strategies; natural and multi-modal communication which mandates common-sense knowledge and the representation of possibly divergent mental models. This article is an attempt to characterise these challenges and to exhibit a set of key decisional issues that need to be addressed for a cognitive robot to successfully share space and tasks with a human. We identify first the needed individual and collaborative cognitive skills: geometric reasoning and situation assessment based on perspective-taking and affordance analysis; acquisition and representation of knowledge models for multiple agents (humans and robots, with their specificities); situated, natural and multi-modal dialogue; human-aware task planning; human–robot joint task achievement. The article discusses each of these abilities, presents working implementations, and shows how they combine in a coherent and original deliberative architecture for human–robot interaction. Supported by experimental results, we eventually show how explicit knowledge management, both symbolic and geometric, proves to be instrumental to richer and more natural human–robot interactions by pushing for pervasive, human-level semantics within the robot's deliberative system

    Die EntzĂĽndungen der SpeicheldrĂĽsen

    No full text

    Die Trigeminusneuralgie

    No full text

    Die Chemotherapie maligner Tumoren im Kiefer-Gesichtsbereich

    No full text

    Applying recommender systems in collaboration environments

    No full text
    Team-based organizational structures are now widely adopted for activities such as product development, customer support and process-improvement initiatives due to their increased likelihood of making better decisions and solving problems. However, team collaboration often faces pitfalls like information overload or misunderstandings due to goal misalignment. In this paper, we put forward the idea that computer-supported collaboration environments can have a positive impact on team collaboration by increasing team members\u2019 awareness, focusing attention on task execution, and fostering the frequency of interaction among team members. We study the impact of recommender systems on team processes in computer-supported collaboration environments, describing the results of two experiments that show how recommendations impact interactions in teams. Teams using recommendations spent less effort on information handling and engaged more in communication than teams without recommendations
    corecore