16,067 research outputs found

    Virtual image out-the-window display system study. Volume 2 - Appendix

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    Virtual image out-the-window display system imaging techniques and simulation devices - appendices containing background materia

    Apollo Lightcraft Project

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    This second year of the NASA/USRA-sponsored Advanced Aeronautical Design effort focused on systems integration and analysis of the Apollo Lightcraft. This beam-powered, single-stage-to-orbit vehicle is envisioned as the shuttlecraft of the 21st century. The five person vehicle was inspired largely by the Apollo Command Module, then reconfigured to include a new front seat with dual cockpit controls for the pilot and co-pilot, while still retaining the 3-abreast crew accommodations in the rear seat. The gross liftoff mass is 5550 kg, of which 500 kg is the payload and 300 kg is the LH2 propellant. The round trip cost to orbit is projected to be three orders of magnitude lower than the current space shuttle orbiter. The advanced laser-driven 5-speed combined-cycle engine has shiftpoints at Mach 1, 5, 11 and 25+. The Apollo Lightcraft can climb into low Earth orbit in three minutes, or fly to any spot on the globe in less than 45 minutes. Detailed investigations of the Apollo Lightcraft Project this second year further evolved the propulsion system design, while focusing on the following areas: (1) man/machine interface; (2) flight control systems; (3) power beaming system architecture; (4) re-entry aerodynamics; (5) shroud structural dynamics; and (6) optimal trajectory analysis. The principal new findings are documented. Advanced design efforts for the next academic year (1988/1989) will center on a one meter+ diameter spacecraft: the Lightcraft Technology Demonstrator (LTD). Detailed engineering design and analyses, as well as critical proof-of-concept experiments, will be carried out on this small, near-term machine. As presently conceived, the LTD could be constructed using state of the art components derived from existing liquid chemical rocket engine technology, advanced composite materials, and high power laser optics

    Super-critical Accretion Flows around Black Holes: Two-dimensional, Radiation-pressure-dominated Disks with Photon-trapping

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    The quasi-steady structure of super-critical accretion flows around a black hole is studied based on the two-dimensional radiation-hydrodynamical (2D-RHD) simulations. The super-critical flow is composed of two parts: the disk region and the outflow regions above and below the disk. Within the disk region the circular motion as well as the patchy density structure are observed, which is caused by Kelvin-Helmholtz instability and probably by convection. The mass-accretion rate decreases inward, roughly in proportion to the radius, and the remaining part of the disk material leaves the disk to form outflow because of strong radiation pressure force. We confirm that photon trapping plays an important role within the disk. Thus, matter can fall onto the black hole at a rate exceeding the Eddington rate. The emission is highly anisotropic and moderately collimated so that the apparent luminosity can exceed the Eddington luminosity by a factor of a few in the face-on view. The mass-accretion rate onto the black hole increases with increase of the absorption opacity (metalicity) of the accreting matter. This implies that the black hole tends to grow up faster in the metal rich regions as in starburst galaxies or star-forming regions.Comment: 16 pages, 12 figures, accepted for publication in ApJ (Volume 628, July 20, 2005 issue

    Using visual analytics to develop situation awareness in astrophysics

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    We present a novel collaborative visual analytics application for cognitively overloaded users in the astrophysics domain. The system was developed for scientists who need to analyze heterogeneous, complex data under time pressure, and make predictions and time-critical decisions rapidly and correctly under a constant influx of changing data. The Sunfall Data Taking system utilizes several novel visualization and analysis techniques to enable a team of geographically distributed domain specialists to effectively and remotely maneuver a custom-built instrument under challenging operational conditions. Sunfall Data Taking has been in production use for 2 years by a major international astrophysics collaboration (the largest data volume supernova search currently in operation), and has substantially improved the operational efficiency of its users. We describe the system design process by an interdisciplinary team, the system architecture and the results of an informal usability evaluation of the production system by domain experts in the context of Endsley's three levels of situation awareness

    Automated biowaste sampling system improved feces collection, mass measurement and sampling

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    The capability of the basic automated Biowaste Sampling System (ABSS) hardware was extended and improved through the design, fabrication and test of breadboard hardware. A preliminary system design effort established the feasibility of integrating the breadboard concepts into the ABSS

    Stereo TV enhancement study Final technical report

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    Human depth perception of television displays in stereo, and nonstereo presentation

    Advanced visual rendering, gesture-based interaction and distributed delivery for immersive and interactive media services

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    The media industry is currently being pulled in the often-opposing directions of increased realism (high resolution, stereoscopic, large screen) and personalisation (selection and control of content, availability on many devices). A capture, production, delivery and rendering system capable of supporting both these trends is being developed by a consortium of European organisations including partners from the broadcast, film, telecoms and academic sectors, in the EU-funded FascinatE project. This paper reports on the latest project developments in the delivery network and end-user device domains, including advanced audiovisual rendering, computer analysis and scripting, content-aware distributed delivery and gesture-based interaction. The paper includes an overview of existing immersive media services and concludes with initial service concept descriptions and their market potential.Peer ReviewedPreprin

    Beyond visualization : designing interfaces to contextualize geospatial data

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    Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (p. 71-74).The growing sensor data collections about our environment have the potential to drastically change our perception of the fragile world we live in. To make sense of such data, we commonly use visualization techniques, enabling public discourse and analysis. This thesis describes the design and implementation of a series of interactive systems that integrate geospatial sensor data visualization and terrain models with various user interface modalities in an educational context to support data analysis and knowledge building using part-digital, part-physical rendering. The main contribution of this thesis is a concrete application scenario and initial prototype of a "Designed Environment" where we can explore the relationship between the surface of Japan's islands, the tension that originates in the fault lines along the seafloor beneath its east coast, and the resulting natural disasters. The system is able to import geospatial data from a multitude of sources on the "Spatial Web", bringing us one step closer to a tangible "dashboard of the Earth."Samuel Luescher.S.M

    Summary of investigations of light scattering in highly reflecting pigmented coatings

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    Light scattering in highly reflecting pigmented coatings - silver bromide and particle suspensions and paint film
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