223,399 research outputs found

    AI2-THOR: An Interactive 3D Environment for Visual AI

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    We introduce The House Of inteRactions (THOR), a framework for visual AI research, available at http://ai2thor.allenai.org. AI2-THOR consists of near photo-realistic 3D indoor scenes, where AI agents can navigate in the scenes and interact with objects to perform tasks. AI2-THOR enables research in many different domains including but not limited to deep reinforcement learning, imitation learning, learning by interaction, planning, visual question answering, unsupervised representation learning, object detection and segmentation, and learning models of cognition. The goal of AI2-THOR is to facilitate building visually intelligent models and push the research forward in this domain

    Research and study in system optimization techniques Second quarterly progress report, Feb. 14 - May 14, 1965

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    Systems optimization for motion stability matrix problem - predictive guidance for Thor vehicle trajector

    A3_9 Flying Thor

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    If Mjolnir can change its mass by controlling gravitons, this may explain how Thor is able to fly. By spinning Mjolnir, angular momentum is gained. Mjolnir looses mass (by manipulating gravitons) as Thor jumps, and so for momentum to be conserved, Thor is able to fly. In order for Thor to fly from the ground to thunder clouds, Mjolnir must have a change in mass of 774 kg

    THOR 2.0: Major Improvements to the Open-Source General Circulation Model

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    THOR is the first open-source general circulation model (GCM) developed from scratch to study the atmospheres and climates of exoplanets, free from Earth- or Solar System-centric tunings. It solves the general non-hydrostatic Euler equations (instead of the primitive equations) on a sphere using the icosahedral grid. In the current study, we report major upgrades to THOR, building upon the work of Mendon\c{c}a et al. (2016). First, while the Horizontally Explicit Vertically Implicit (HEVI) integration scheme is the same as that described in Mendon\c{c}a et al. (2016), we provide a clearer description of the scheme and improved its implementation in the code. The differences in implementation between the hydrostatic shallow (HSS), quasi-hydrostatic deep (QHD) and non-hydrostatic deep (NHD) treatments are fully detailed. Second, standard physics modules are added: two-stream, double-gray radiative transfer and dry convective adjustment. Third, THOR is tested on additional benchmarks: tidally-locked Earth, deep hot Jupiter, acoustic wave, and gravity wave. Fourth, we report that differences between the hydrostatic and non-hydrostatic simulations are negligible in the Earth case, but pronounced in the hot Jupiter case. Finally, the effects of the so-called "sponge layer", a form of drag implemented in most GCMs to provide numerical stability, are examined. Overall, these upgrades have improved the flexibility, user-friendliness, and stability of THOR.Comment: 57 pages, 31 figures, revised, accepted for publication in ApJ

    When Big Brother Privatizes: Commercial Surveillance, the Privacy Act of 1974, and the Future of RFID

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    RFID is a powerful new technology that has the potential to allow commercial retailers to undermine individual control over private information. Despite the potential of RFID to undermine personal control over such information, the federal government has not enacted a set of practicable standards to ensure that personal data does not become widely misused by commercial entities. Although some potential privacy abuses could be addressed by modifying RFID technology, this iBrief argues that it would be wise to amend the Privacy Act of 1974 so that corporations would have a statutory obligation to preserve individual anonymity and respect the privacy preferences of consumers

    The Official Student Newspaper of UAS

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    UAS Answers: Everybody's got one... -- URECA (If I were eligible, this notice would not exist) -- Submitting to Tidal Echoes -- Pizza with the Provost -- Annual Native Olympics -- 'Thor': The Dumb World -- Life after college: Are you ready? -- Campus Calenda

    The Evaluation of a Test Device for Human Occupant Restraint (THOR) Under Vertical Loading Conditions: Part 1 - Experimental Setup and Results

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    A series of 16 vertical tests were conducted on a Test Device for Human Occupant Restraint (THOR) - NT 50th percentile Anthropomorphic Test Device (ATD) at NASA Langley Research Center (LaRC). The purpose of the tests conducted at NASA LaRC was threefold. The first was to add vertical response data to the growing test database for THOR-NT development and validation. Second, the THOR-NT analytical computational models currently in development must be validated for the vertical loading environment. The computational models have been calibrated for frontal crash environments with concentration on accurately replicating head/neck, thoracic, and lower extremity responses. Finally, familiarity with the THOR ATD is necessary because NASA is interested in evaluating advanced ATDs for use in future flight and research projects. The THOR was subjected to vertical loading conditions ranging between 5 and 16 g in magnitude and 40 to 120 milliseconds (msec) in duration. It was also tested under conditions identical to previous tests conducted on the Hybrid II and III ATDs to allow comparisons to be made. Variations in the test setup were also introduced, such as the addition of a footrest in an attempt to offload some of the impact load into the legs. A full data set of the THOR-NT ATD will be presented and discussed. Results from the tests show that the THOR was largely insensitive to differences in the loading conditions, perhaps due in part to their small magnitudes. THOR responses, when compared to the Hybrid II and III in the lumbar region, demonstrated that the THOR more closely resembled the straight spine Hybrid setup. In the neck region, the THOR behaved more like the Hybrid III. However in both cases, the responses were not identical, indicating that the THOR would show differences in response than the Hybrid II and III ATDs when subjected to identical impact conditions. The addition of a footrest did not significantly affect the THOR response due to the nature of how the loading conditions were applied

    Ballast water management: technology choice comparing TODIM and THOR 2

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    This paper approaches the problem of ballast water treatment in ships. This has been identified as one of the four greatest threats to the world’s oceans. Solutions that have been considered for solving the problem are alternative water treatment technologies. In the case study reported in this paper three major water treatment technologies have been evaluated with the help of twenty-six criteria, quantitative as well as qualitative by using two discrete multicriteria methods, TODIM and THOR 2. The THOR 2 consists of the axiomatic evolution of the THOR method and both THOR 2 and THOR are made available through the THOR Web platform. Five groups of evaluation criteria are then considered: practicality; biological effectiveness; cost/benefit ratio; time frame for the implementation of standards; and environmental impact of the process' sub-products. In this paper a case study on choosing a ballast water treatment technology is presented. Three alternative ballast water management technologies are proposed by experts in the field and are evaluated with the help of twenty-six criteria, quantitative as well as qualitative. Each ballast water management method is described by a list of twenty-six attributes or criteria. After setting the problem in a clear way and consulting different experts, the two separate applications of both TODIM and THOR 2 are performed. What is denoted as Management Method #1 is indeed chosen as the best alternative according to both methods. The conclusion is that those two methods, although conceptually and analytically quite different, lead essentially to the same main results.  Two other applications of both TODIM and THOR have indeed confirmed the convergence of results in spite of the conceptual and technical differences between the two methods. This suggests that formulating a decision problem in a correct, clear-cut way can be at least as important as the technical characteristics of the method per se

    TORSO DEFORMATION IN FRONTAL SLED TESTS: COMPARISION BETWEEN THOR NT, THOR NT WITH THE CHALMERS SD-1 SHOULDER, AND PMHS

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    This study compares the thoracic deformation response of the 50th percentile male THOR NT frontal crash dummy and the response of the THOR modified with the SD-1 shoulder (THOR SD-1) relative to the thoracic response of eight 50th percentile male PMHS. The prototype Chalmers University SD-1 shoulder was designed to be more human-like in terms of geometry and range of motion in comparison to the standard THOR NT shoulder. The dummies and PMHS were restrained by a three-point restraint in a driver-side configuration and were subjected to a simulated 40 km/h frontal crash. The most prominent difference between the responses of the dummies and PMHS involved motion of the lower right anterior ribcage measurement site that is the farthest lateral distance from the diagonal shoulder belt. During the impact event, this site moved substantially anteriorly and away from the spine for the PMHS. The PMHS lower right “bulge out” behavior is believed to be caused by inertial loading of the ribcage, underlying organs, and soft tissue overlying the torso. The THOR SD-1 shoulder altered the shoulder belt position relative to the thoracic deflection measurement sites resulting in a different distribution of deformation for the upper measurement sites although the average upper site deformation was similar to that recorded for the standard THOR shoulder
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