324 research outputs found

    Planning and scheduling research at NASA Ames Research Center

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    Planning and scheduling is the area of artificial intelligence research that focuses on the determination of a series of operations to achieve some set of (possibly) interacting goals and the placement of those operations in a timeline that allows them to be accomplished given available resources. Work in this area at the NASA Ames Research Center ranging from basic research in constrain-based reasoning and machine learning, to the development of efficient scheduling tools, to the application of such tools to complex agency problems is described

    Operational efficiency subpanel advanced mission control

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    Herein, the term mission control will be taken quite broadly to include both ground and space based operations as well as the information infrastructure necessary to support such operations. Three major technology areas related to advanced mission control are examined: (1) Intelligent Assistance for Ground-Based Mission Controllers and Space-Based Crews; (2) Autonomous Onboard Monitoring, Control and Fault Detection Isolation and Reconfiguration; and (3) Dynamic Corporate Memory Acquired, Maintained, and Utilized During the Entire Vehicle Life Cycle. The current state of the art space operations are surveyed both within NASA and externally for each of the three technology areas and major objectives are discussed from a user point of view for technology development. Ongoing NASA and other governmental programs are described. An analysis of major research issues and current holes in the program are provided. Several recommendations are presented for enhancing the technology development and insertion process to create advanced mission control environments

    The 1990 progress report and future plans

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    This document describes the progress and plans of the Artificial Intelligence Research Branch (RIA) at ARC in 1990. Activities span a range from basic scientific research to engineering development and to fielded NASA applications, particularly those applications that are enabled by basic research carried out at RIA. Work is conducted in-house and through collaborative partners in academia and industry. Our major focus is on a limited number of research themes with a dual commitment to technical excellence and proven applicability to NASA short, medium, and long-term problems. RIA acts as the Agency's lead organization for research aspects of artificial intelligence, working closely with a second research laboratory at JPL and AI applications groups at all NASA centers

    Diurnal and nocturnal temperatures for Atlantic salmon postsmolts (Salmo salar L.) during their early marine life

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    Data storage tags (DSTs) were applied to Atlantic salmon (Salmo salar L.) smolts during their seaward migration in the spring of 2002 at a fish counting fence on Campbellton River, Newfoundland. Our objectives were to discover whether or not salmon smolts could carry DSTs and survive, whether or not useful data on thermal habitat could be obtained and interpreted, and whether or not salmon smolts moved vertically in the water column. Data were downloaded from 15 of the recovered tags and revealed the hourly water temperatures experienced by the fish for periods of 3 to 71 days. The data on the DSTs were analyzed for temperature patterns in relation to migration behavior and diurnal movement of the fish. While in the sea, the DSTs recorded night temperatures of 12.5°C, which were higher than day temperatures of 11.6°C; the record from moored recorders, however, indicated that sea temperatures actually declined at night. It is hypothesized that posts-molts avoid avian predators during daylight hours by positioning themselves deeper in the water column and that they were pursuing prey during the deeper vertical descents or ascents noted during the periods of more rapid changes in temperature

    Future applications of artificial intelligence to Mission Control Centers

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    Future applications of artificial intelligence to Mission Control Centers are presented in the form of the viewgraphs. The following subject areas are covered: basic objectives of the NASA-wide AI program; inhouse research program; constraint-based scheduling; learning and performance improvement for scheduling; GEMPLAN multi-agent planner; planning, scheduling, and control; Bayesian learning; efficient learning algorithms; ICARUS (an integrated architecture for learning); design knowledge acquisition and retention; computer-integrated documentation; and some speculation on future applications

    Building Intelligent Systems: Artificial Intelligence Research at NASA Ames Research Center

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    The goal of building autonomous, intelligent systems is the major focus of both basic and applied research in artificial intelligence within NASA. This paper discusses the components that make up that goal and describes ongoing work at the NASA Ames Research Center to achieve the goal. NASA provides a unique environment for fostering the development of intelligent computational systems; the test domains, especially Space Station systems, represent both a welldefined need, and a marvelous series of increasingly more difficult problems for testing research ideas. One can see a clear progression of systems through research settings (both within and external to NASA) to space station testbeds to systems which actually fly on space station

    Impact of aging on the auditory system and related cognitive functions: A narrative review

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    Age-related hearing loss (ARHL), presbycusis, is a chronic health condition that affects approximately one-third of the world’s population. The peripheral and central hearing alterations associated with age-related hearing loss have a profound impact on perception of verbal and non-verbal auditory stimuli. The high prevalence of hearing loss in the older adults corresponds to the increased frequency of dementia in this population. Therefore, researchers have focused their attention on age-related central effects that occur independent of the peripheral hearing loss as well as central effects of peripheral hearing loss and its association with cognitive decline and dementia. Here we review the current evidence for the age-related changes of the peripheral and central auditory system and the relationship between hearing loss and pathological cognitive decline and dementia. Furthermore, there is a paucity of evidence on the relationship between ARHL and established biomarkers of Alzheimer’s disease, as the most common cause of dementia. Such studies are critical to be able to consider any causal relationship between dementia and ARHL. While this narrative review will examine the pathophysiological alterations in both the peripheral and central auditory system and its clinical implications, the question remains unanswered whether hearing loss causes cognitive impairment or vice versa

    Preface

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    Mission-Based Serious Games for Cross-Cultural Communication Training

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    Appropriate cross-cultural communication requires a critical skill set that is increasingly being integrated into regular military training regimens. By enabling a higher order of communication skills, military personnel are able to interact more effectively in situations that involve local populations, host nation forces, and multinational partners. The Virtual Cultural Awareness Trainer (VCAT) is specifically designed to help address these needs. VCAT is deployed by Joint Forces Command (JFCOM) on Joint Knowledge Online (JKO) as a means to provide online, mission-based culture and language training to deploying and deployed troops. VCAT uses a mix of game-based learning, storytelling, tutoring, and remediation to assist in developing the component skills required for successful intercultural communication in mission-based settings

    Simulation of Radiation-Induced Damage Distribution to evaluate Models for Higher-Order Chromosome Organisation

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    The structure of chromatin at the level of the 30 nm fibre has been studied in considerable detail, but little is known about how this fibre is arranged within the interphase chromosome territory. Over the years, various polymer models were developed to simulate chromosome structure, for example the random-walk/giant-loop (RWGL) model, the multi-loop subcompartment (MLS) model, and the interconnected-fibre-loop model (Friedland et al., 1999). These models differ mainly in the size and arrangement of the chromatin loops and, correspondingly, in the predicted distribution of chromatin density within the nucleus. It occurred to us that densely ionising radiation can be used to probe the actual distribution of chromatin density in human interphase cells. In contrast to sparsely ionising radiation (e.g. X-rays), which induces DNA double-strand breaks (DSB) that are distributed randomly within the nucleus, irradiation with densely ionising accelerated ions leads to spatial clustering of DSB. This inhomogeneity in DSB localisation, together with an inhomogeneity of DNA density within the nucleus, causes an over-dispersion in the resulting distribution of DNA fragment sizes that can be detected by pulsed-field gel electrophoresis. Using the above-mentioned chromosome models, we performed computer simulations to predict the DNA fragment size distributions resulting from irradiation with accelerated ions, and compared the predicted distributions with those obtained experimentally. We found that simulations based on the MLS model, in which local variations in chromatin density are higher than in the other models, resulted in the best agreement between calculation and experiment
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