2,821 research outputs found

    OPTIMAL PAYLOAD DESIGN FOR THE NAVY'S FUTURE UAS

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    The Tern is a future Navy unmanned aerial system that will deploy on and launch from surface ships such as destroyers. It is designed to be capable of performing multiple types of sorties such as anti-submarine warfare; information, surveillance, and reconnaissance; and acting as a node in a communication network. Each type of sortie has different operational and physical requirements manifested in the payload onboard the Tern. There are two forms a payload can take: fixed and modular. The fixed payload is hard-wired into the Tern while the modular payload space on the Tern supports the ability to change the payloads for each sortie. Multiple possible scenarios and operational postures add another level of complexity in determining optimal payload configurations. The overarching issue that we will address in this research is the general design of the Tern payload. This design must take into account the inherent stochasticity of the situations in which the Tern will operate. While conducting a primary task within a sortie, the Tern could also be called to carry out other tasks as the situation dictates. For every possible realization of a sortie a Tern is sent on, there is an optimal payload design that addresses the possible tasks in the sortie. Consequently, each design satisfies a given measure of effectiveness with a certain expected effectiveness. The objective is to find a global payload design that maximizes responsiveness over all possible sorties and scenarios.NAVAIRhttp://archive.org/details/optimalpayloadde1094559617Ensign, United States NavyApproved for public release; distribution is unlimited

    Master of Science

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    thesisWe present a straightforward, easy-to-implement, point-based approach for animating elastoplastic materials. The core idea of our approach is the introduction of embedded space-the least-squares best fit of the material's rest state into three dimensions. Together with plastic offsets that map embedded space to rest space, the embedded space allows us to robustly estimate the deformation gradient, compute elastic forces, and account for plastic flow. We additionally introduce an estimate for the volume of a particle, opening the door for nonuniform sampling, and describe a technique to increase the robustness of point-based elastic simulation. Our approach can handle arbitrarily large elastic deformations and extreme plastic deformations. Because the approach is point-based, there is no need for complex remeshing-the corresponding operation is a simple neighborhood query in embedded space. We demonstrate our approach on a variety of examples that display a wide range of material behaviors

    Global Journalism Ethics: Widening the Conceptual Base

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    For most of its history, journalism ethics has been highly practical in aim, in theorizing, and in application. Inquiry analyzed what was occurring inside newsrooms and its scope was parochial. Starting from the premise that a parochial approach no longer serves journalism, the study of journalism, or the public of journalism, in this paper it is argued that a major task of journalism ethics is to construct a more non-parochial ethics—a global journalism ethics informed by critical work from various disciplines and cultures. The discussion presented charts the trajectory of journalism ethics over several centuries to explain the role of parochialism and the limits of theorizing in journalism ethics. This historical perspective also serves as a foundation for outlining what a future journalism ethics might look like, if we widen the conceptual base by incorporating new knowledge of media from outside journalism ethics, and by redefining journalism ethics as a global enterprise

    A Free and Undemocratic Press?

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    Papers presented for the Center for the Study of Ethics in Society Western Michigan University

    Developing 'robust performance benchmarks' for the next Australian Health Care Agreement: the need for a new framework

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    If the outcomes of the recent COAG meeting are implemented, Australia will have a new set of benchmarks for its health system within a few months. This is a non-trivial task. Choice of benchmarks will, explicitly or implicitly, reflect a framework about how the health system works, what is important or to be valued and how the benchmarks are to be used. In this article we argue that the health system is dynamic and so benchmarks need to measure flows and interfaces rather than simply cross-sectional or static performance. We also argue that benchmarks need to be developed taking into account three perspectives: patient, clinician and funder. Each of these perspectives is critical and good performance from one perspective or on one dimension doesn't imply good performance on either (or both) of the others

    Event-Based Driver Performance Assessment

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    Driving is an intermittent control task during which drivers manage their work across a number of driving and non-driving sub-tasks. The multitasking nature forces drivers to adopt situated safety margins (tolerances) in terms of time-headway (THW), time-to-collision (TTC), time-to-linecrossing (TLC), etc. Unacceptable situations (i.e. violations of safety margins defined here as events) are characterized by corrective maneuvers or actions. The frequency with which corrective actions are necessary (bandwidth), the hazard level of the situation that inspired these actions (performance), and the rate and magnitude of the responses to these situations (effort) provide a rich signature of how drivers manage their task(s). We hypothesize that drivers’ perception of performance and effort are founded in the characteristics of experienced events. This is explored by comparing driving characteristics of bus drivers who drive on the shoulder of a highway with and without the support of a haptic lateral support system (LSS). Subjective performance and effort scores extracted from a usability questionnaire and objective ones from our event-based analysis show highly significant correspondence when comparing supported versus unsupported driving. This provides validating support for the adopted event-based approach. The proposed approach offers not only sensitive metrics of driver performance and effort to evaluate ITS applications but also explanatory power by exposing the various strategically different ways drivers are affected by these systems. This method of quantifying and analyzing driver data affords new opportunities to evaluate driver responses to ITS applications

    Event-Based Driver Performance Assessment

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    Driving is an intermittent control task during which drivers manage their work across a number of driving and non-driving sub-tasks. The multitasking nature forces drivers to adopt situated safety margins (tolerances) in terms of time-headway (THW), time-to-collision (TTC), time-to-linecrossing (TLC), etc. Unacceptable situations (i.e. violations of safety margins defined here as events) are characterized by corrective maneuvers or actions. The frequency with which corrective actions are necessary (bandwidth), the hazard level of the situation that inspired these actions (performance), and the rate and magnitude of the responses to these situations (effort) provide a rich signature of how drivers manage their task(s). We hypothesize that drivers’ perception of performance and effort are founded in the characteristics of experienced events. This is explored by comparing driving characteristics of bus drivers who drive on the shoulder of a highway with and without the support of a haptic lateral support system (LSS). Subjective performance and effort scores extracted from a usability questionnaire and objective ones from our event-based analysis show highly significant correspondence when comparing supported versus unsupported driving. This provides validating support for the adopted event-based approach. The proposed approach offers not only sensitive metrics of driver performance and effort to evaluate ITS applications but also explanatory power by exposing the various strategically different ways drivers are affected by these systems. This method of quantifying and analyzing driver data affords new opportunities to evaluate driver responses to ITS applications

    Small grain forage yields at Overton for 1997-1998 and three-year means

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    Last updated: 10/19/201
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