2,736 research outputs found

    Deployable platform systems development

    Get PDF
    The long range objective is to achieve technology readiness for one or more deployable platform systems by 1986. Engineering plans and approaches to meet this goal are presented in outline form

    Quantification of Cross-coupling and Motion Feedthrough for Multiaxis Controllers Used in an Air Combat Flying Task

    Get PDF
    A real-time piloted simulation of an air-to-air combat flying task using a wings-level-turn aircraft and various novel controllers was conducted. One objective is to quantify how the pilot interacts with the controllers and control modes, including: (1) controller versus aircraft response; (2) proprioceptive cross-coupling among axes of the controllers; and (3) biodynamic cross-coupling between the aircraft motions and the controllers. In order to aid in identifying the items listed above, both the target aircraft and the large amplitude multimode aerospace research simulator (LAMARS) motion system were distributed with quasi-random sums-of-sinusoids. Since the disturbances were separated in frequency, spectral analysis techniques were used to identify the three items listed. The results of the spectral analysis of controller motions from the two-axis side stick, a twist grip mounted on the side stick, a thumb button mounted on the side stick, and conventional rudder pedals are presented. Conclusions and recommendations for further research are also presented

    Cellular distribution of the prion protein in palatine tonsils of mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus nelsoni)

    Get PDF
    Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) that affects members of the Cervidae family, including deer (Odocoileus spp.), elk (Cervus Canadensis spp.), and moose (Alces alces spp.). While CWD is a neurodegenerative disease, lymphoid accumulation of the abnormal isoform of the prion protein (PrPSc) is detectable early in the course of infection. It has been shown that a large portion of the PrPSc lymphoid accumulation in infected mule deer takes place on the surface of follicular dendritic cells (FDCs). In mice, FDC expression of PrPC has been shown to be essential for PrPSc accumulation. FDCs have been shown to normally express high levels of PrPC in mice and humans but this has not been examined in natural hosts for CWD. We used double immunofluorescent labeling and confocal microscopy to determine the PrPC expression characteristics of B and T lymphocytes as well as FDCs in palatine tonsils of CWD-negative mule deer and elk. We detected substantial PrPC colocalization with all cellular phenotypic markers used in this study, not just with FDC phenotypic markers

    A preliminary look at control augmented dynamic response of structures

    Get PDF
    The augmentation of structural characteristics, mass, damping, and stiffness through the use of control theory in lieu of structural redesign or augmentation was reported. The standard single-degree-of-freedom system was followed by a treatment of the same system using control augmentation. The system was extended to elastic structures using single and multisensor approaches and concludes with a brief discussion of potential application to large orbiting space structures

    Space Shuttle Main Engine (SSME) Pogo testing and results

    Get PDF
    To effectively assess the Pogo stability of the space shuttle vehicle, it was necessary to characterize the structural, propellant, and propulsion dynamics subsystems. Extensive analyses and comprehensive testing programs were established early in the project as an implementation of management philosophy of Pogo prevention for space shuttle. The role of the space shuttle main engine (SSMF) in the Pogo prevention plans, the results obtained from engine ground testing with analysis, and measured data from STS-1 flight are discussed

    Gas Bubbles Emerging from a Submerged Granular Bed

    Full text link
    This fluid dynamics video was submitted to the Gallery of Fluid Motion for the 2009 APS Division of Fluid Dynamics Meeting in Minneapolis, Minnesota. In this video we show some results from a simple experiment where air was injected by a single nozzle at known constant flow rates in the bottom of a granular bed submerged in water. The injected air propagates through the granular bed in one of two modes. Mode 1 emergence involves small discrete bubbles taking tortuous paths through the interstitial space of the bed. Multiple small bubbles can be emitted from the bed in an array of locations at the same time during Mode 1 emergence. Mode 2 emergence involves large discrete bubbles locally fluidizing the granular bed and exiting the bed approximately above the injection site. Bead diameter, bead density, and air flow rate were varied to investigate the change in bubble release behavior at the top of the granular bed. This system is a useful model for methane seeps in lakes. Methane bubbles are released from the decomposition of organic matter in the lake bed. The initial size of the bubble determines how much of the gas is absorbed into the lake and how much of the gas reaches the surface and is released into the atmosphere. The size and behavior of the emerging bubbles may also affect the amount of vertical mixing occurring in the lake, as well as the mixing from the lake bed into the benthic layer.Comment: 2009 APS DFD Gallery of Fluid Motion Submissio

    Criminal History and LSI-R Scores of RSAT Participants in the State of Massachusetts: Impact of Offender Age on Program Completion and Rates of Offender Recidivism

    Get PDF
    The purpose of this study was to understand how offender age impacted residential substance abuse treatment (RSAT) program success in reducing rates of recidivism for offenders exiting the judicial system. Despite passing legislation in the 1980s and 1990s, which increased the penalties for certain crimes, offender recidivism remains high, with no apparent drop in the number of incarcerations and re-incarcerations, resulting in high costs and threats to the safety and quality of life experienced within communities. Social learning theory, behavioral decision theory, and biologically based theories of behavior were the theoretical foundations. Archival data collected from a RSAT grant program at between January 1, 1999 and June 6, 2001 were examined. Data related to participant scores on the Level of Service Inventory Revised (LSI-R), acquired prior to program placement and upon program completion, were compared with the number of incarcerations before and after program completion; charges for convictions already decided and/or pending convictions, age at admission(s) and age at the time of the offender\u27s first offense, and types of offenses (domestic or sexual) committed were explored in a factor analysis. Negative correlations identified included: sex offenders and their age at admission and between LSI-R scores and completing the RSAT program. Positive correlations identified included: new convictions and completing the RSAT program, age at admission to program and age of first offense, and date of first offense and sex offender variables. Implications for positive social change include reduced rates of recidivism among offenders with substance abuse problems

    Inhalation therapy in influenza

    Get PDF

    Minority Representation: A Political or Judicial Question

    Get PDF

    The 1962 Congressional Redistricting in Kentucky

    Get PDF
    corecore