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Sample records for aircraft sca handled

  1. Shuttle Carrier Aircraft (SCA) Fleet Photo

    NASA Technical Reports Server (NTRS)

    1995-01-01

    NASA's two Boeing 747 Shuttle Carrier Aircraft (SCA) are seen here nose to nose at Dryden Flight Research Center, Edwards, California. The front mounting attachment for the Shuttle can just be seen on top of each. The SCAs are used to ferry Space Shuttle orbiters from landing sites back to the launch complex at the Kennedy Space Center, and also to and from other locations too distant for the orbiters to be delivered by ground transportation. The orbiters are placed atop the SCAs by Mate-Demate Devices, large gantry-like structures which hoist the orbiters off the ground for post-flight servicing, and then mate them with the SCAs for ferry flights. Features which distinguish the two SCAs from standard 747 jetliners are; three struts, with associated interior structural strengthening, protruding from the top of the fuselage (two aft, one forward) on which the orbiter is attached, and two additional vertical stabilizers, one on each end of the standard horizontal stabilizer, to enhance directional stability. The two SCAs are under the operational control of NASA's Johnson Space Center, Houston, Texas. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back

  2. Shuttle Carrier Aircraft (SCA) Fleet Photo

    NASA Technical Reports Server (NTRS)

    1995-01-01

    NASA's two Boeing 747 Shuttle Carrier Aircraft (SCA) are seen here nose to nose at Dryden Flight Research Center, Edwards, California. The front mounting attachment for the Shuttle can just be seen on top of each. The SCAs are used to ferry Space Shuttle orbiters from landing sites back to the launch complex at the Kennedy Space Center, and also to and from other locations too distant for the orbiters to be delivered by ground transportation. The orbiters are placed atop the SCAs by Mate-Demate Devices, large gantry-like structures which hoist the orbiters off the ground for post-flight servicing, and then mate them with the SCAs for ferry flights. Features which distinguish the two SCAs from standard 747 jetliners are; three struts, with associated interior structural strengthening, protruding from the top of the fuselage (two aft, one forward) on which the orbiter is attached, and two additional vertical stabilizers, one on each end of the standard horizontal stabilizer, to enhance directional stability. The two SCAs are under the operational control of NASA's Johnson Space Center, Houston, Texas. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back

  3. Aircraft handling qualities data

    NASA Technical Reports Server (NTRS)

    Heffley, R. K.; Jewell, W. F.

    1972-01-01

    Available information on weight and inertia, aerodynamic derivatives, control characteristics, and stability augmentation systems is documented for 10 representative contemporary airplanes. Data sources are given for each airplane. Flight envelopes are presented and dimensional derivatives, transfer functions for control inputs, and several selected handling qualities parameters have been computed and are tabulated for 10 different flight conditions including the power approach configuration. The airplanes documented are the NT-33A, F-104A, F-4C, X-15, HL-10, Jetstar, CV-880M, B-747, C-5A, and XB-70A.

  4. Factors influencing aircraft ground handling performance

    NASA Technical Reports Server (NTRS)

    Yager, T. J.

    1983-01-01

    Problems associated with aircraft ground handling operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research results from tests with instrumented ground vehicles and aircraft, and aircraft wet runway accident investigation are summarized to indicate the effects of different aircraft, tire, and runway parameters. Several promising means are described for improving tire/runway water drainage capability, brake system efficiency, and pilot training to help optimize aircraft traction performance on wet runways.

  5. An Investigation of Large Aircraft Handling Qualities

    NASA Astrophysics Data System (ADS)

    Joyce, Richard D.

    An analytical technique for investigating transport aircraft handling qualities is exercised in a study using models of two such vehicles, a Boeing 747 and Lockheed C-5A. Two flight conditions are employed for climb and directional tasks, and a third included for a flare task. The analysis technique is based upon a "structural model" of the human pilot developed by Hess. The associated analysis procedure has been discussed previously in the literature, but centered almost exclusively on the characteristics of high-performance fighter aircraft. The handling qualities rating level (HQRL) and pilot induced oscillation tendencies rating level (PIORL) are predicted for nominal configurations of the aircraft and for "damaged" configurations where actuator rate limits are introduced as nonlinearites. It is demonstrated that the analysis can accommodate nonlinear pilot/vehicle behavior and do so in the context of specific flight tasks, yielding estimates of handling qualities, pilot-induced oscillation tendencies and upper limits of task performance. A brief human-in-the-loop tracking study was performed to provide a limited validation of the pilot model employed.

  6. Comparison of ScaRaB, GOES 8, Aircraft, and Surface Observations of the Absorption of Solar Radiation by Clouds

    NASA Technical Reports Server (NTRS)

    Pope, Shelly K.; Valero, Francisco P. J.; Collins, William D.; Minnis, Patrick

    2002-01-01

    Data obtained by the Scanner for Radiation Budget (ScaRaB) instrument on the Meteor 3 satellite have been analyzed and compared to satellite (GOES 8), aircraft (Radiation Measurement System, RAMS), and surface (Baseline Solar Radiation Network (BSRN), Solar and Infrared Observations System (SIROS), and RAMS) measurements of irradiance obtained during the Atmospheric Radiation Measurements Enhanced Shortwave Experiment (ARESE). It is found that the ScaRaB data covering the period from March 1994 to February 1995 (the instrument's operational lifetime) indicate excess absorption of solar radiation by the cloudy atmosphere in agreement with previous aircraft, surface, and GOES 8 results. The full ScaRaB data set combined with BSRN and SIROS surface observations gives an average all-sky absorptance of 0.28. The GOES 8 data set combined with RAMS surface observations gives an average all-sky absorptance of 0.26. The aircraft data set (RAMS) gives a mean all-sky absorptance of 0.24 (for the column between 0.5 and 13 km).

  7. STS-76 - Being Prepared for Delivery to Kennedy Space Center via SCA 747 Aircraft

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Moonrise over Atlantis following the STS-76 dawn landing at NASA's Dryden Flight Research Center, Edwards, California, on 31 March 1996. NASA 905, one of two modified Boeing 747 Shuttle Carrier Aircraft (SCA), was readied to ferry Atlantis back to the Kennedy Space Center, Florida. Delivery of Atlantis to Florida was delayed until 11 April 1996, due to an engine warning light that appeared shortly after take off on 6 April. The SCA #905 returned to Edwards with Atlantis attached only minutes after departure. The right inboard engine #3 was exchanged and the 747 with Atlantis atop was able to depart for Davis-Monthan Air Force Base for a refueling stop. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the

  8. STS-76 - Being Prepared for Delivery to Kennedy Space Center via SCA 747 Aircraft

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Moonrise over Atlantis following the STS-76 dawn landing at NASA's Dryden Flight Research Center, Edwards, California, on 31 March 1996. NASA 905, one of two modified Boeing 747 Shuttle Carrier Aircraft (SCA), was readied to ferry Atlantis back to the Kennedy Space Center, Florida. Delivery of Atlantis to Florida was delayed until 11 April 1996, due to an engine warning light that appeared shortly after take off on 6 April. The SCA #905 returned to Edwards with Atlantis attached only minutes after departure. The right inboard engine #3 was exchanged and the 747 with Atlantis atop was able to depart for Davis-Monthan Air Force Base for a refueling stop. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the

  9. STS-35 Leaves Dryden on 747 Shuttle Carrier Aircraft (SCA) Bound for Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The first rays of the morning sun light up the side of NASA's Boeing 747 Shuttle Carrier Aircraft (SCA) as it departs for the Kennedy Space Center, Florida, with the orbiter from STS-35 attached to its back. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and can be reused on future flights. Some of these orbital laboratories, like the Spacelab, provide facilities for several specialists to conduct experiments in such fields as medicine, astronomy, and materials manufacturing. Some types of satellites deployed by Space Shuttles include those involved in environmental and resources protection, astronomy, weather forecasting, navigation, oceanographic studies, and other

  10. Recent progress towards predicting aircraft ground handling performance

    NASA Technical Reports Server (NTRS)

    Yager, T. J.; White, E. J.

    1981-01-01

    Capability implemented in simulating aircraft ground handling performance is reviewed and areas for further expansion and improvement are identified. Problems associated with providing necessary simulator input data for adequate modeling of aircraft tire/runway friction behavior are discussed and efforts to improve tire/runway friction definition, and simulator fidelity are described. Aircraft braking performance data obtained on several wet runway surfaces are compared to ground vehicle friction measurements. Research to improve methods of predicting tire friction performance are discussed.

  11. STS-76 - Being Prepared for Delivery to Kennedy Space Center via SCA 747 Aircraft

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Moonrise over Atlantis: following the STS-76 dawn landing at NASA's Dryden Flight Research Center, Edwards, California, on 31 March 1996, NASA 905, one of two modified Boeing 747 Shuttle Carrier Aircraft, was prepared to ferry Atlantis back to the Kennedy Space Center, FL. Delivery of Altlantis to Florida was delayed until 11 April 1996, due to an engine warning light that appeared shortly after take off on April 6. The SCA #905 returned to Edwards only minutes after departure. The right inboard engine #3 was exchanged and the 747 with Atlantis atop was able to depart for Davis-Monthan Air Force Base for a refueling stop. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth

  12. STS-76 - Being Prepared for Delivery to Kennedy Space Center via SCA 747 Aircraft

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Moonrise over Atlantis: the space shuttle Atlantis receives post-flight servicing in the Mate-Demate Device (MDD), following its landing at NASA's Dryden Flight Research Center, Edwards, California, 31 March 1996. Once servicing was complete, one of NASA's two 747 Shuttle Carrier Aircraft, No. 905, was readied to ferry Atlantis back to the Kennedy Space Center, Florida. Delivery of Atlantis to Florida was delayed until 11 April 1996, due to an engine warning light that appeared shortly after take off on April 6. The SCA returned to Edwards only minutes after departure. The right inboard engine #3 was exchanged, and the 747 with Atlantis atop was able to depart 11 April for Davis-Monthan Air Force Base for a refueling stop. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside

  13. STS-76 - SCA 747 Aircraft Takeoff for Delivery to Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    1996-01-01

    NASA's Boeing 747 Shuttle Carrier Aircraft leaves the runway with the Shuttle Atlantis on its back. Following the STS-76 dawn landing at NASA's Dryden Flight Research Center, Edwards, California, on 31 March 1996. NASA 905, one of two modified 747's, was prepared to ferry Atlantis back to the Kennedy Space Center, FL. Delivery of Altlantis to Florida was delayed until 11 April 1996, due to an engine warning light that appeared shortly after take off on 6 April. The SCA #905 returned to Edwards with Atlantis aboard only minutes after departure. The right inboard engine #3 was exchanged and the 747 with Atlantis atop was able to depart for Davis-Monthan Air Force Base for a refueling stop. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the

  14. STS-76 - Being Prepared for Delivery to Kennedy Space Center via SCA 747 Aircraft

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Moonrise over Atlantis: the space shuttle Atlantis receives post-flight servicing in the Mate-Demate Device (MDD), following its landing at NASA's Dryden Flight Research Center, Edwards, California, 31 March 1996. Once servicing was complete, one of NASA's two 747 Shuttle Carrier Aircraft, No. 905, was readied to ferry Atlantis back to the Kennedy Space Center, Florida. Delivery of Atlantis to Florida was delayed until 11 April 1996, due to an engine warning light that appeared shortly after take off on April 6. The SCA returned to Edwards only minutes after departure. The right inboard engine #3 was exchanged, and the 747 with Atlantis atop was able to depart 11 April for Davis-Monthan Air Force Base for a refueling stop. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside

  15. STS-76 - SCA 747 Aircraft Takeoff for Delivery to Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    1996-01-01

    NASA's Boeing 747 Shuttle Carrier Aircraft leaves the runway with the Shuttle Atlantis on its back. Following the STS-76 dawn landing at NASA's Dryden Flight Research Center, Edwards, California, on 31 March 1996. NASA 905, one of two modified 747's, was prepared to ferry Atlantis back to the Kennedy Space Center, FL. Delivery of Altlantis to Florida was delayed until 11 April 1996, due to an engine warning light that appeared shortly after take off on 6 April. The SCA #905 returned to Edwards with Atlantis aboard only minutes after departure. The right inboard engine #3 was exchanged and the 747 with Atlantis atop was able to depart for Davis-Monthan Air Force Base for a refueling stop. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the

  16. STS-76 - Being Prepared for Delivery to Kennedy Space Center via SCA 747 Aircraft

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Moonrise over Atlantis: following the STS-76 dawn landing at NASA's Dryden Flight Research Center, Edwards, California, on 31 March 1996, NASA 905, one of two modified Boeing 747 Shuttle Carrier Aircraft, was prepared to ferry Atlantis back to the Kennedy Space Center, FL. Delivery of Altlantis to Florida was delayed until 11 April 1996, due to an engine warning light that appeared shortly after take off on April 6. The SCA #905 returned to Edwards only minutes after departure. The right inboard engine #3 was exchanged and the 747 with Atlantis atop was able to depart for Davis-Monthan Air Force Base for a refueling stop. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth

  17. [A Handling Qualities Metric for Damaged Aircraft

    NASA Technical Reports Server (NTRS)

    Cogan, Bruce; Hayes, Peggy

    2009-01-01

    In recent flight tests of F-15 Intelligent Flight Control System (IFCS), software simulated aircraft control surface failures were inserted to evaluate the IFCS adaptive systems. The failure commanded the left stabilator to a fixed position. The adaptive system uses a neural network that is designed to change control law gains, in the event of damage (real or simulated), that allows the aircraft to fly as it had before the damage. The performance of the adaptive system was assessed in terms of its ability to re-establish good onboard model tracking and its ability to decouple roll and pitch response.

  18. Handling Qualities of Large Flexible Aircraft. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Poopaka, S.

    1980-01-01

    The effects on handling qualities of elastic modes interaction with the rigid body dynamics of a large flexible aircraft are studied by a mathematical computer simulation. An analytical method to predict the pilot ratings when there is a severe modes interactions is developed. This is done by extending the optimal control model of the human pilot response to include the mode decomposition mechanism into the model. The handling qualities are determined for a longitudinal tracking task using a large flexible aircraft with parametric variations in the undamped natural frequencies of the two lowest frequency, symmetric elastic modes made to induce varying amounts of mode interaction.

  19. Recent Progress Towards Predicting Aircraft Ground Handling Performance

    NASA Technical Reports Server (NTRS)

    Yager, T. J.; White, E. J.

    1981-01-01

    The significant progress which has been achieved in development of aircraft ground handling simulation capability is reviewed and additional improvements in software modeling identified. The problem associated with providing necessary simulator input data for adequate modeling of aircraft tire/runway friction behavior is discussed and efforts to improve this complex model, and hence simulator fidelity, are described. Aircraft braking performance data obtained on several wet runway surfaces is compared to ground vehicle friction measurements and, by use of empirically derived methods, good agreement between actual and estimated aircraft braking friction from ground vehilce data is shown. The performance of a relatively new friction measuring device, the friction tester, showed great promise in providing data applicable to aircraft friction performance. Additional research efforts to improve methods of predicting tire friction performance are discussed including use of an instrumented tire test vehicle to expand the tire friction data bank and a study of surface texture measurement techniques.

  20. Modeling procedures for handling qualities evaluation of flexible aircraft

    NASA Technical Reports Server (NTRS)

    Govindaraj, K. S.; Eulrich, B. J.; Chalk, C. R.

    1981-01-01

    This paper presents simplified modeling procedures to evaluate the impact of flexible modes and the unsteady aerodynamic effects on the handling qualities of Supersonic Cruise Aircraft (SCR). The modeling procedures involve obtaining reduced order transfer function models of SCR vehicles, including the important flexible mode responses and unsteady aerodynamic effects, and conversion of the transfer function models to time domain equations for use in simulations. The use of the modeling procedures is illustrated by a simple example.

  1. Unified Theory for Aircraft Handling Qualities and Adverse Aircraft-Pilot Coupling

    NASA Technical Reports Server (NTRS)

    Hess, R. A.

    1997-01-01

    A unified theory for aircraft handling qualities and adverse aircraft-pilot coupling or pilot-induced oscillations is introduced. The theory is based on a structural model of the human pilot. A methodology is presented for the prediction of (1) handling qualities levels; (2) pilot-induced oscillation rating levels; and (3) a frequency range in which pilot-induced oscillations are likely to occur. Although the dynamics of the force-feel system of the cockpit inceptor is included, the methodology will not account for effects attributable to control sensitivity and is limited to single-axis tasks and, at present, to linear vehicle models. The theory is derived from the feedback topology of the structural model and an examination of flight test results for 32 aircraft configurations simulated by the U.S. Air Force/CALSPAN NT-33A and Total In-Flight Simulator variable stability aircraft. An extension to nonlinear vehicle dynamics such as that encountered with actuator saturation is discussed.

  2. New aircraft configurations handling qualities studies based on the aerodynamic invariant concept

    NASA Astrophysics Data System (ADS)

    Bazile, J.

    2013-12-01

    This paper proposes an innovative approach to go deeper in the Handling Qualities knowledge for New Aircraft Configurations based on the Aerodynamic Invariant Concept. By manipulating the Doublet Lattice Method for aerodynamic derivatives computation, an Aerodynamic Invariant can be highlighted. It contributes to many aircraft dynamics parameters and can be considered as "key driver" of the longitudinal aircraft dynamics. The aim of this new approach is to study the impact of this aerodynamic invariant on aircraft Handling Qualities and to ask the question: "Could this aerodynamic invariant be used in parallel with Performance in the conceptual design phase to "seek" New Aircraft configurations capable of achieving further Handling Qualities improvement with Performance benefits?" The enclosed results highlight that the aerodynamic invariant could allow to improve and to optimize the aircraft Handling Qualities by relaxing the aircraft dynamics stability.

  3. Analysis of Aircraft Control Performance using a Fuzzy Rule Base Representation of the Cooper-Harper Aircraft Handling Quality Rating

    NASA Technical Reports Server (NTRS)

    Tseng, Chris; Gupta, Pramod; Schumann, Johann

    2006-01-01

    The Cooper-Harper rating of Aircraft Handling Qualities has been adopted as a standard for measuring the performance of aircraft since it was introduced in 1966. Aircraft performance, ability to control the aircraft, and the degree of pilot compensation needed are three major key factors used in deciding the aircraft handling qualities in the Cooper- Harper rating. We formulate the Cooper-Harper rating scheme as a fuzzy rule-based system and use it to analyze the effectiveness of the aircraft controller. The automatic estimate of the system-level handling quality provides valuable up-to-date information for diagnostics and vehicle health management. Analyzing the performance of a controller requires a set of concise design requirements and performance criteria. Ir, the case of control systems fm a piloted aircraft, generally applicable quantitative design criteria are difficult to obtain. The reason for this is that the ultimate evaluation of a human-operated control system is necessarily subjective and, with aircraft, the pilot evaluates the aircraft in different ways depending on the type of the aircraft and the phase of flight. In most aerospace applications (e.g., for flight control systems), performance assessment is carried out in terms of handling qualities. Handling qualities may be defined as those dynamic and static properties of a vehicle that permit the pilot to fully exploit its performance in a variety of missions and roles. Traditionally, handling quality is measured using the Cooper-Harper rating and done subjectively by the human pilot. In this work, we have formulated the rules of the Cooper-Harper rating scheme as fuzzy rules with performance, control, and compensation as the antecedents, and pilot rating as the consequent. Appropriate direct measurements on the controller are related to the fuzzy Cooper-Harper rating system: a stability measurement like the rate of change of the cost function can be used as an indicator if the aircraft is under

  4. A survey of handling qualities criteria and their applications to high performance aircraft

    NASA Technical Reports Server (NTRS)

    Peahl, D. L.; Kolkailah, F.; Sandlin, D. R.

    1986-01-01

    Various handling qualities criteria and their application to high performance aircraft including state-of-the-art and highly augmented aircraft were surveyed. Neal-Smith, Bandwidth, Equivalent Systems, and Military Specification 8785 criteria are applied to flight test data from aircraft such as the F-8 Digital Fly-By-Wire, the YF-12, and an Advanced Fighter Aircraft. Backgrounds and example applications of each criteria are given. The results show that the handling qualities criteria investigated can be applied to highly augmented aircraft with fairly good results in most cases; however, since no one method excelled, more than one criteria should be used whenever possible. Equivalent time delays appear to be the most frequent critical factor in determining pilot rating levels of highly augmented aircraft.

  5. Endeavour Mated to SCA Time-Lapse

    NASA Video Gallery

    At the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, space shuttle Endeavour is mounted atop NASA's Shuttle Carrier Aircraft, or SCA, in preparation for its ferry flight to Ca...

  6. Handling Qualities Prediction of an F-16XL-Based Reduced Sonic Boom Aircraft

    NASA Technical Reports Server (NTRS)

    Cogan, Bruce; Yoo, Seung

    2010-01-01

    A major goal of the Supersonics Project under NASA s Fundamental Aeronautics program is sonic boom reduction of supersonic aircraft. An important part of this effort is development and validation of sonic boom prediction tools used in aircraft design. NASA Dryden s F- 16XL was selected as a potential testbed aircraft to provide flight validation. Part of this task was predicting the handling qualities of the modified aircraft. Due to the high cost of modifying the existing F-16XL control laws, it was desirable to find modifications that reduced the aircraft sonic boom but did not degrade baseline aircraft handling qualities allowing for the potential of flight test without changing the current control laws. This was not a requirement for the initial modification design work, but an important consideration for proceeding to the flight test option. The primary objective of this work was to determine an aerodynamic and mass properties envelope of the F-16XL aircraft. The designers could use this envelope to determine the effect of proposed modifications on aircraft handling qualities.

  7. A design procedure for the handling qualities optimization of the X-29A aircraft

    NASA Technical Reports Server (NTRS)

    Bosworth, John T.; Cox, Timothy H.

    1989-01-01

    A design technique for handling qualities improvement was developed for the X-29A aircraft. As with any new aircraft, the X-29A control law designers were presented with a relatively high degree of uncertainty in their mathematical models. The presence of uncertainties, and the high level of static instability of the X-29A caused the control law designers to stress stability and robustness over handling qualities. During flight test, the mathematical models of the vehicle were validated or corrected to match the vehicle dynamic behavior. The updated models were then used to fine tune the control system to provide fighter-like handling characteristics. A design methodology was developed which works within the existing control system architecture to provide improved handling qualities and acceptable stability with a minimum of cost in both implementation as well as software verification and validation.

  8. Analysis of flexible aircraft longitudinal dynamics and handling qualities. Volume 1: Analysis methods

    NASA Technical Reports Server (NTRS)

    Waszak, M. R.; Schmidt, D. S.

    1985-01-01

    As aircraft become larger and lighter due to design requirements for increased payload and improved fuel efficiency, they will also become more flexible. For highly flexible vehicles, the handling qualities may not be accurately predicted by conventional methods. This study applies two analysis methods to a family of flexible aircraft in order to investigate how and when structural (especially dynamic aeroelastic) effects affect the dynamic characteristics of aircraft. The first type of analysis is an open loop model analysis technique. This method considers the effects of modal residue magnitudes on determining vehicle handling qualities. The second method is a pilot in the loop analysis procedure that considers several closed loop system characteristics. Volume 1 consists of the development and application of the two analysis methods described above.

  9. A design procedure for the handling qualities optimization of the X-29A aircraft

    NASA Technical Reports Server (NTRS)

    Bosworth, John T.; Cox, Timothy H.

    1989-01-01

    The techniques used to improve the pitch-axis handling qualities of the X-29A wing-canard-planform fighter aircraft are reviewed. The aircraft and its FCS are briefly described, and the design method, which works within the existing FCS architecture, is characterized in detail. Consideration is given to the selection of design goals and design variables, the definition and calculation of the cost function, the validation of the mathematical model on the basis of flight-test data, and the validation of the improved design by means of nonlinear simulations. Flight tests of the improved design are shown to verify the simulation results.

  10. Handling qualities related to stall/spin accidents of supersonic fighter aircraft

    NASA Technical Reports Server (NTRS)

    Anderson, S. B.

    1984-01-01

    This paper reviews the handling qualities which influence the high angle of attack (AOA) behavior of supersonic fighter aircraft in order to obtain a clearer understanding of the causes of stall/spin accidents. The results show that, because modern fighters suffer more serious consequences when control is lost, good handling qualities are essential for safe operation at high AOA. Relaxed static stability used on some fighter aircraft can result in control problems at high AOA owing to inertia coupling and the difficulty of a recovery from a deep stall. Indications are that the use of departure/spin resistance and an automatic spin prevention system will greatly improve the safety record for modern supersonic fighters.

  11. Prediction of aircraft handling qualities using analytical models of the human pilot

    NASA Technical Reports Server (NTRS)

    Hess, R. A.

    1982-01-01

    The optimal control model (OCM) of the human pilot is applied to the study of aircraft handling qualities. Attention is focused primarily on longitudinal tasks. The modeling technique differs from previous applications of the OCM in that considerable effort is expended in simplifying the pilot/vehicle analysis. After briefly reviewing the OCM, a technique for modeling the pilot controlling higher order systems is introduced. Following this, a simple criterion for determining the susceptibility of an aircraft to pilot induced oscillations is formulated. Finally, a model based metric for pilot rating prediction is discussed. The resulting modeling procedure provides a relatively simple, yet unified approach to the study of a variety of handling qualities problems.

  12. Analysis of flexible aircraft longitudinal dynamics and handling qualities. Volume 2: Data

    NASA Technical Reports Server (NTRS)

    Waszak, M. R.; Schmidt, D. K.

    1985-01-01

    Two analysis methods are applied to a family of flexible aircraft in order to investigate how and when structural (especially dynamic aeroelastic) effects affect the dynamic characteristics of aircraft. The first type of analysis is an open loop modal analysis technique. This method considers the effect of modal residue magnitudes on determining vehicle handling qualities. The second method is a pilot in the loop analysis procedure that considers several closed loop system characteristics. Both analyses indicated that dynamic aeroelastic effects caused a degradation in vehicle tracking performance, based on the evaluation of some simulation results. Volume 2 consists of the presentation of the state variable models of the flexible aircraft configurations used in the analysis applications mode shape plots for the structural modes, numerical results from the modal analysis frequency response plots from the pilot in the loop analysis and a listing of the modal analysis computer program.

  13. Longitudinal handling qualities during approach and landing of a powered lift STOL aircraft

    NASA Technical Reports Server (NTRS)

    Franklin, J. A.; Innis, R. C.

    1972-01-01

    Longitudinal handling qualities evaluations were conducted on the Ames Research Center Flight Simulator for Advanced Aircraft (FSAA) for the approach and landing tasks of a powered lift STOL research aircraft. The test vehicle was a C-8A aircraft modified with a new wing incorporating internal blowing over an augmentor flap. The investigation included: (1) use of various flight path and airspeed control techniques for the basic vehicle; (2) assessment of stability and command augmentation schemes for pitch attitude and airspeed control; (3) determination of the influence of longitudinal and vertical force coupling for the power control; (4) determination of the influence of pitch axis coupling with the thrust vector control; and (5) evaluations of the contribution of stability and command augmentation to recovery from a single engine failure. Results are presented in the form of pilot ratings and commentary substantiated by landing approach time histories.

  14. An Examination of Handling Qualities Criteria for V/STOL Aircraft

    NASA Technical Reports Server (NTRS)

    Anderson, Seth B.

    1960-01-01

    A study has been undertaken to define hand-ling qualities criteria for V/STOL aircraft. With the current military requirements for helicopters and airplanes as a framework, modifications and additions were made for conversion to a preliminary set of V/STOL requirements using a broad background of flight experience and pilots' comments from VTOL and STOL aircraft, BLC (boundary-layer-control) equipped aircraft, variable stability aircraft, flight simulators and landing approach studies. The report contains a discussion of the reasoning behind and the sources of information leading to suggested requirements. The results of the study indicate that the majority of V/STOL requirements can be defined by modifications to the helicopter and/or airplane requirements by appropriate definition of reference speeds. Areas where a requirement is included but where the information is felt to be inadequate to establish a firm quantitative requirement include the following: Control power and damping relationships about all axes for various sizes and types of aircraft; control power, sensitivity, d-amping and response for height control; dynamic longitudinal and dynamic lateral- directional stability in the transition region, including emergency operation; hovering steadiness; acceleration and deceleration in transition; descent rates and flight-path angles in steep approaches, and thrust margin for approach.

  15. Piloted Simulation Assessment of the Impact of Flexible Structures on Handling Qualities of Generic Supersonic Aircraft

    NASA Technical Reports Server (NTRS)

    Stringer, Mary T.; Cowen, Brandon; Hoffler, Keith D.; Couch, Jesse C.; Ogburn, Marilyn E.; Diebler, Corey G.

    2013-01-01

    The NASA Langley Research Center Cockpit Motion Facility (CMF) was used to conduct a piloted simulation assessment of the impact of flexible structures on flying qualities. The CMF was used because of its relatively high bandwidth, six degree-of-freedom motion capability. Previous studies assessed and attempted to mitigate the effects of multiple dynamic aeroservoelastic modes (DASE). Those results indicated problems existed, but the specific cause and effect was difficult to ascertain. The goal of this study was to identify specific DASE frequencies, damping ratios, and gains that cause degradation in handling qualities. A generic aircraft simulation was developed and designed to have Cooper-Harper Level 1 handling qualities when flown without DASE models. A test matrix of thirty-six DASE modes was implemented. The modes had frequencies ranging from 1 to 3.5 Hz and were applied to each axis independently. Each mode consisted of a single axis, frequency, damping, and gain, and was evaluated individually by six subject pilots with test pilot backgrounds. Analysis completed to date suggests that a number of the DASE models evaluated degrade the handling qualities of this class of aircraft to an uncontrollable condition.

  16. Factors affecting handling qualities of a lift-fan aircraft during steep terminal area approaches

    NASA Technical Reports Server (NTRS)

    Gerdes, R. M.; Hynes, C. S.

    1975-01-01

    The XV-5B lift-fan aircraft was used to explore the factors affecting handling qualities in the terminal area. A 10 deg ILS approach task was selected to explore these problems. Interception of the glide slope at 457.2 m, glide slope tracking, deceleration along the glide slope to a spot hover were considered. Variations in airplane deck angle, deceleration schedule, and powered-lift management were studied. The overall descent performance envelope was identified on the basis of fan stall, maximum comfortable descent rate, and controllability restrictions. The collective-lift stick provided precise glide slope tracking capability. The pilot preferred a deck-parallel attitude for which he used powered lift to control glide slope and pitch attitude to keep the angle of attack near zero. Workload was reduced when the deceleration schedule was delayed until the aircraft was well established on the glide slope, since thrust vector changes induced flight path disturbances.

  17. Flight Validation of a Handling Qualities Metric for a Damaged Aircraft

    NASA Technical Reports Server (NTRS)

    Cogan, Bruce R.

    2009-01-01

    Objectives: a) Develop an asymmetric handling qualities metric to predict cross coupling effects of a damaged aircraft: 1) Initial use of U.S Army Aeronautical Design Specification ADS-33; 2) Modification as required based on flight test results. b) Simulation and Flight Validation of proposed metric: 1) F-16 VISTA (March 2010); 2) F-18 Full Scale Test bed (Potential Early Experiment); and 3) Flight Simulators (GTM, ACFS, F-18 HILS). c) Provide flight validated metric and tool box to control law designers.

  18. Modal control theory and application to aircraft lateral handling qualities design

    NASA Technical Reports Server (NTRS)

    Srinathkumar, S.

    1978-01-01

    A multivariable synthesis procedure based on eigenvalue/eigenvector assignment is reviewed and is employed to develop a systematic design procedure to meet the lateral handling qualities design objectives of a fighter aircraft over a wide range of flight conditions. The closed loop modal characterization developed provides significant insight into the design process and plays a pivotal role in the synthesis of robust feedback systems. The simplicity of the synthesis algorithm yields an efficient computer aided interactive design tool for flight control system synthesis.

  19. A modal analysis of flexible aircraft dynamics with handling qualities implications

    NASA Technical Reports Server (NTRS)

    Schmidt, D. K.

    1983-01-01

    A multivariable modal analysis technique is presented for evaluating flexible aircraft dynamics, focusing on meaningful vehicle responses to pilot inputs and atmospheric turbulence. Although modal analysis is the tool, vehicle time response is emphasized, and the analysis is performed on the linear, time-domain vehicle model. In evaluating previously obtained experimental pitch tracking data for a family of vehicle dynamic models, it is shown that flexible aeroelastic effects can significantly affect pitch attitude handling qualities. Consideration of the eigenvalues alone, of both rigid-body and aeroelastic modes, does not explain the simulation results. Modal analysis revealed, however, that although the lowest aeroelastic mode frequency was still three times greater than the short-period frequency, the rigid-body attitude response was dominated by this aeroelastic mode. This dominance was defined in terms of the relative magnitudes of the modal residues in selected vehicle responses.

  20. Estimation of Handling Qualities Parameters of the Tu-144 Supersonic Transport Aircraft from Flight Test Data

    NASA Technical Reports Server (NTRS)

    Curry, Timothy J.; Batterson, James G. (Technical Monitor)

    2000-01-01

    Low order equivalent system (LOES) models for the Tu-144 supersonic transport aircraft were identified from flight test data. The mathematical models were given in terms of transfer functions with a time delay by the military standard MIL-STD-1797A, "Flying Qualities of Piloted Aircraft," and the handling qualities were predicted from the estimated transfer function coefficients. The coefficients and the time delay in the transfer functions were estimated using a nonlinear equation error formulation in the frequency domain. Flight test data from pitch, roll, and yaw frequency sweeps at various flight conditions were used for parameter estimation. Flight test results are presented in terms of the estimated parameter values, their standard errors, and output fits in the time domain. Data from doublet maneuvers at the same flight conditions were used to assess the predictive capabilities of the identified models. The identified transfer function models fit the measured data well and demonstrated good prediction capabilities. The Tu-144 was predicted to be between level 2 and 3 for all longitudinal maneuvers and level I for all lateral maneuvers. High estimates of the equivalent time delay in the transfer function model caused the poor longitudinal rating.

  1. Enterprise Separates from 747 SCA for First Tailcone off Free Flight

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The Space Shuttle prototype Enterprise rises from NASA's 747 Shuttle Carrier Aircraft (SCA) to begin a powerless glide flight back to NASA's Dryden Flight Research Center, Edwards, California, on its fourth of the five free flights in the shuttle program's Approach and Landing Tests (ALT), 12 October 1977. The tests were carried out at Dryden to verify the aerodynamic and control characteristics of the orbiters in preparation for the first space mission with the orbiter Columbia in April 1981. The Space Shuttle Approach and Landings Tests (ALT) program allowed pilots and engineers to learn how the Space Shuttle and the modified Boeing 747 Shuttle Carrier Aircraft (SCA) handled during low-speed flight and landing. The Enterprise, a prototype of the Space Shuttles, and the SCA were flown to conduct the approach and landing tests at the NASA Dryden Flight Research Center, Edwards, California, from February to October 1977. The first flight of the program consisted of the Space Shuttle Enterprise attached to the Shuttle Carrier Aircraft. These flights were to determine how well the two vehicles flew together. Five 'captive-inactive' flights were flown during this first phase in which there was no crew in the Enterprise. The next series of captive flights was flown with a flight crew of two on board the prototype Space Shuttle. Only three such flights proved necessary. This led to the free-flight test series. The free-flight phase of the ALT program allowed pilots and engineers to learn how the Space Shuttle handled in low-speed flight and landing attitudes. For these landings, the Enterprise was flown by a crew of two after it was released from the top of the SCA. The vehicle was released at altitudes ranging from 19,000 to 26,000 feet. The Enterprise had no propulsion system, but its first four glides to the Rogers Dry Lake runway provided realistic, in-flight simulations of how subsequent Space Shuttles would be flown at the end of an orbital mission. The fifth

  2. Emissions of NOx, particle mass and particle numbers from aircraft main engines, APU's and handling equipment at Copenhagen Airport

    NASA Astrophysics Data System (ADS)

    Winther, Morten; Kousgaard, Uffe; Ellermann, Thomas; Massling, Andreas; Nøjgaard, Jacob Klenø; Ketzel, Matthias

    2015-01-01

    This paper presents a detailed emission inventory for NOx, particle mass (PM) and particle numbers (PN) for aircraft main engines, APU's and handling equipment at Copenhagen Airport (CPH) based on time specific activity data and representative emission factors for the airport. The inventory has a high spatial resolution of 5 m × 5 m in order to be suited for further air quality dispersion calculations. Results are shown for the entire airport and for a section of the airport apron area ("inner apron") in focus. The methodology presented in this paper can be used to quantify the emissions from aircraft main engines, APU and handling equipment in other airports. For the entire airport, aircraft main engines is the largest source of fuel consumption (93%), NOx, (87%), PM (61%) and PN (95%). The calculated fuel consumption [NOx, PM, PN] shares for APU's and handling equipment are 5% [4%, 8%, 5%] and 2% [9%, 31%, 0%], respectively. At the inner apron area for handling equipment the share of fuel consumption [NOx, PM, PN] are 24% [63%, 75%, 2%], whereas APU and main engines shares are 43% [25%, 19%, 54%], and 33% [11%, 6%, 43%], respectively. The inner apron NOx and PM emission levels are high for handling equipment due to high emission factors for the diesel fuelled handling equipment and small for aircraft main engines due to small idle-power emission factors. Handling equipment is however a small PN source due to the low number based emission factors. Jet fuel sulphur-PM sensitivity calculations made in this study with the ICAO FOA3.0 method suggest that more than half of the PM emissions from aircraft main engines at CPH originate from the sulphur content of the fuel used at the airport. Aircraft main engine PN emissions are very sensitive to the underlying assumptions. Replacing this study's literature based average emission factors with "high" and "low" emission factors from the literature, the aircraft main engine PN emissions were estimated to change with a

  3. Sudden Cardiac Arrest (SCA) Risk Assessment

    MedlinePlus

    ... Find a Specialist Share Twitter Facebook SCA Risk Assessment Sudden Cardiac Arrest (SCA) occurs abruptly and without ... of all ages and health conditions. Start Risk Assessment The Sudden Cardiac Arrest (SCA) Risk Assessment Tool ...

  4. Prediction of pilot opinion ratings using an optimal pilot model. [of aircraft handling qualities in multiaxis tasks

    NASA Technical Reports Server (NTRS)

    Hess, R. A.

    1977-01-01

    A brief review of some of the more pertinent applications of analytical pilot models to the prediction of aircraft handling qualities is undertaken. The relative ease with which multiloop piloting tasks can be modeled via the optimal control formulation makes the use of optimal pilot models particularly attractive for handling qualities research. To this end, a rating hypothesis is introduced which relates the numerical pilot opinion rating assigned to a particular vehicle and task to the numerical value of the index of performance resulting from an optimal pilot modeling procedure as applied to that vehicle and task. This hypothesis is tested using data from piloted simulations and is shown to be reasonable. An example concerning a helicopter landing approach is introduced to outline the predictive capability of the rating hypothesis in multiaxis piloting tasks.

  5. Development of longitudinal handling qualities criteria for large advanced supersonic aircraft

    NASA Technical Reports Server (NTRS)

    Sudderth, R. W.; Bohn, J. G.; Caniff, M. A.; Bennett, G. R.

    1975-01-01

    Longitudinal handling qualities criteria in terms of airplane response characteristics were developed. The criteria cover high speed cruise maneuvering, landing approach, and stall recovery. Data substantiating the study results are reported.

  6. Aircraft model prototypes which have specified handling-quality time histories

    NASA Technical Reports Server (NTRS)

    Johnson, S. H.

    1976-01-01

    Several techniques for obtaining linear constant-coefficient airplane models from specified handling-quality time histories are discussed. One technique, the pseudodata method, solves the basic problem, yields specified eigenvalues, and accommodates state-variable transfer-function zero suppression. The method is fully illustrated for a fourth-order stability-axis small-motion model with three lateral handling-quality time histories specified. The FORTRAN program which obtains and verifies the model is included and fully documented.

  7. Aircraft model prototypes which have specified handling-quality time histories

    NASA Technical Reports Server (NTRS)

    Johnson, S. H.

    1978-01-01

    Several techniques for obtaining linear constant-coefficient airplane models from specified handling-quality time histories are discussed. The pseudodata method solves the basic problem, yields specified eigenvalues, and accommodates state-variable transfer-function zero suppression. The algebraic equations to be solved are bilinear, at worst. The disadvantages are reduced generality and no assurance that the resulting model will be airplane like in detail. The method is fully illustrated for a fourth-order stability-axis small motion model with three lateral handling quality time histories specified. The FORTRAN program which obtains and verifies the model is included and fully documented.

  8. Interpreting the handling qualities of aircraft with stability and control augmentation

    NASA Technical Reports Server (NTRS)

    Hodgkinson, J.; Potsdam, E. H.; Smith, R. E.

    1990-01-01

    The general process of designing an aircraft for good flying qualities is first discussed. Lessons learned are pointed out, with piloted evaluation emerging as a crucial element. Two sources of rating variability in performing these evaluations are then discussed. First, the finite endpoints of the Cooper-Harper scale do not bias parametric statistical analyses unduly. Second, the wording of the scale does introduce some scatter. Phase lags generated by augmentation systems, as represented by equivalent time delays, often cause poor flying qualities. An analysis is introduced which allows a designer to relate any level of time delay to a probability of loss of aircraft control. This view of time delays should, it is hoped, allow better visibility of the time delays in the design process.

  9. An approach to the determination of aircraft handling qualities using pilot transfer functions

    NASA Technical Reports Server (NTRS)

    Adams, J. J.; Hatch, H. G., Jr.

    1978-01-01

    It was shown that a correlation exists between pilot-aircraft system closed-loop characteristics, determined by using analytical expressions for pilot response along with the analytical expression for the aircraft response, and pilot ratings obtained in many previous flight and simulation studies. Two different levels of preferred pilot response were used. These levels were: (1) a static gain and a second-order lag function with a lag time constant of 0.2 second; and (2) a static gain, a lead time constant of 1 second, and a 0.2-second lag time constant. If a system response with a pitch-angle time constant of 2.6 seconds and a stable oscillatory mode of motion with a period of 2.5 seconds could be achieved with the first-level pilot model, it was shown that the pilot rating will be satisfactory for that vehicle.

  10. Effects of higher order control systems on aircraft approach and landing longitudinal handling qualities

    NASA Technical Reports Server (NTRS)

    Pasha, M. A.; Dazzo, J. J.; Silverthorn, J. T.

    1982-01-01

    An investigation of approach and landing longitudinal flying qualities, based on data generated using a variable stability NT-33 aircraft combined with significant control system dynamics is described. An optimum pilot lead time for pitch tracking, flight path angle tracking, and combined pitch and flight path angle tracking tasks is determined from a closed loop simulation using integral squared error (ISE) as a performance measure. Pilot gain and lead time were varied in the closed loop simulation of the pilot and aircraft to obtain the best performance for different control system configurations. The results lead to the selection of an optimum lead time using ISE as a performance criterion. Using this value of optimum lead time, a correlation is then found between pilot rating and performance with changes in the control system and in the aircraft dynamics. It is also shown that pilot rating is closely related to pilot workload which, in turn, is related to the amount of lead which the pilot must generate to obtain satisfactory response. The results also indicate that the pilot may use pitch angle tracking for the approach task and then add flight path angle tracking for the flare and touchdown.

  11. Longitudinal Handling Qualities of the Tu-144LL Airplane and Comparisons With Other Large, Supersonic Aircraft

    NASA Technical Reports Server (NTRS)

    Cox, Timothy H.; Marshall, Alisa

    2000-01-01

    Four flights have been conducted using the Tu-144LL supersonic transport aircraft with the dedicated objective of collecting quantitative data and qualitative pilot comments. These data are compared with the following longitudinal flying qualities criteria: Neal-Smith, short-period damping, time delay, control anticipation parameter, phase delay (omega(sp)*T(theta(2))), pitch bandwidth as a function of time delay, and flight path as a function of pitch bandwidth. Determining the applicability of these criteria and gaining insight into the flying qualities of a large, supersonic aircraft are attempted. Where appropriate, YF-12, XB-70, and SR-71 pilot ratings are compared with the Tu-144LL results to aid in the interpretation of the Tu-144LL data and to gain insight into the application of criteria. The data show that approach and landing requirements appear to be applicable to the precision flightpath control required for up-and-away flight of large, supersonic aircraft. The Neal-Smith, control anticipation parameter, and pitch-bandwidth criteria tend to correlate with the pilot comments better than the phase delay criterion, omega(sp)*T(theta(2)). The data indicate that the detrimental flying qualities implication of decoupled pitch-attitude and flightpath responses occurring for high-speed flight may be mitigated by requiring the pilot to close the loop on flightpath or vertical speed.

  12. Spinocerebellar Ataxia Type 5 (SCA5)

    MedlinePlus

    ... areas of the brain. It is considered a “pure cerebellar ataxia.” What is the prognosis for SCA5? ... SCA5 have, on rare occasions, been reported in individuals under age 20. Those individuals with early onset ...

  13. Spinocerebellar Ataxia Type 10 (SCA10)

    MedlinePlus

    ... onset, coordination of hands and arms becomes impaired. Fine motor skills such as handwriting and fastening buttons ... that causes SCA10. DNA tests for SCA10 involve analysis of a gene located on chromosome 22q13. (Each ...

  14. Flight performance using a hyperstereo helmet-mounted display: aircraft handling

    NASA Astrophysics Data System (ADS)

    Jennings, Sion A.; Craig, Gregory L.; Stuart, Geoffrey W.; Kalich, Melvyn E.; Rash, Clarence E.; Harding, Thomas H.

    2009-05-01

    A flight study was conducted to assess the impact of hyperstereopsis on helicopter handling proficiency, workload and pilot acceptance. Three pilots with varying levels of night vision goggle and hyperstereo helmet-mounted display experience participated in the test. The pilots carried out a series of flights consisting of low-level maneuvers over a period of two weeks. Four of the test maneuvers, The turn around the tail, the hard surface landing, the hover height estimation and the tree-line following were analysed in detail. At the end of the testing period, no significant difference was observed in the performance data, between maneuvers performed with the TopOwl helmet and maneuvers performed with the standard night vision goggle. This study addressed only the image intensification display aspects of the TopOwl helmet system. The tests did not assess the added benefits of overlaid symbology or head slaved infrared camera imagery. These capabilities need to be taken into account when assessing the overall usefulness of the TopOwl system. Even so, this test showed that pilots can utilize the image intensification imagery displayed on the TopOwl to perform benign night flying tasks to an equivalent level as pilots using ANVIS. The study should be extended to investigate more dynamic and aggressive low level flying, slope landings and ship deck landings. While there may be concerns regarding the effect of hyperstereopsis on piloting, this initial study suggests that pilots can either adapt or compensate for hyperstereo effects with sufficient exposure and training. Further analysis and testing is required to determine the extent of training required.

  15. Aircraft

    DOEpatents

    Hibbs, B.D.; Lissaman, P.B.S.; Morgan, W.R.; Radkey, R.L.

    1998-09-22

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing`s top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gases for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well. 31 figs.

  16. Aircraft

    DOEpatents

    Hibbs, Bart D.; Lissaman, Peter B. S.; Morgan, Walter R.; Radkey, Robert L.

    1998-01-01

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gasses for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well.

  17. DC-8 Airborne Laboratory in flight over NASA Dryden center with SCA 747 on ramp

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The DC-8 aircraft is seen making a banking turn high above the NASA Dryden ramp. This view of the DC-8's left side reveals some of the modifications necessary for particular on-board experiments. To the right of the DC-8 is the edge of Rogers Dry Lake. Above the aircraft's forward fuselage is the Dryden Flight Research Center headquarters building, while other NASA facilities extend down the flightline to the right. Below the DC-8 is the Shuttle Carrier Aircraft (SCA), on which are visible attachment points for the Shuttle Orbiter.

  18. No parkinsonism in SCA2 and SCA3 despite severe neurodegeneration of the dopaminergic substantia nigra.

    PubMed

    Schöls, Ludger; Reimold, Matthias; Seidel, Kay; Globas, Christoph; Brockmann, Kathrin; Hauser, Till Karsten; Auburger, Georg; Bürk, Katrin; den Dunnen, Wilfred; Reischl, Gerald; Korf, Horst-Werner; Brunt, Ewout R; Rüb, Udo

    2015-11-01

    See Klockgether (doi:10.1093/awv253) for a scientific commentary on this article.The spinocerebellar ataxias types 2 (SCA2) and 3 (SCA3) are autosomal dominantly inherited cerebellar ataxias which are caused by CAG trinucleotide repeat expansions in the coding regions of the disease-specific genes. Although previous post-mortem studies repeatedly revealed a consistent neurodegeneration of the dopaminergic substantia nigra in patients with SCA2 and with SCA3, parkinsonian motor features evolve only rarely. As the pathophysiological mechanism how SCA2 and SCA3 patients do not exhibit parkinsonism is still enigmatic, we performed a positron emission tomography and a post-mortem study of two independent cohorts of SCA2 and SCA3 patients with and without parkinsonian features. Positron emission tomography revealed a significant reduction of dopamine transporter levels in the striatum as well as largely unaffected postsynaptic striatal D2 receptors. In spite of this remarkable pathology in the motor mesostriatal pathway, only 4 of 19 SCA2 and SCA3 patients suffered from parkinsonism. The post-mortem investigation revealed, in addition to an extensive neuronal loss in the dopaminergic substantia nigra of all patients with spinocerebellar ataxia, a consistent affection of the thalamic ventral anterior and ventral lateral nuclei, the pallidum and the cholinergic pedunculopontine nucleus. With the exception of a single patient with SCA3 who suffered from parkinsonian motor features during his lifetime, the subthalamic nucleus underwent severe neuronal loss, which was clearly more severe in its motor territory than in its limbic or associative territories. Our observation that lesions of the motor territory of the subthalamic nucleus were consistently associated with the prevention of parkinsonism in our SCA2 and SCA3 patients matches the clinical experience that selective targeting of the motor territory of the subthalamic nucleus by focal lesions or deep brain stimulation

  19. The use of an aircraft test stand for VTOL handling qualities studies. [pilot evaluation of flight controllability

    NASA Technical Reports Server (NTRS)

    Pauli, F. A.; Corliss, L. D.; Selan, S. D.; Gerdes, R. M.; Gossett, T. D.

    1974-01-01

    The VTOL flight tests stand for testing control concepts on the X-14B VSS aircraft in hover, is described. This stand permits realistic and safe piloted evaluation and checkout of various control systems and of parameter variations within each system to determine acceptability to the pilot. Pilots can use it as a practical training tool to practice procedures and flying techniques and become familiar with the aircraft characteristics. Some examples of test experience are given. The test stand allows the X14B to maneuver in hover from centered position + or - 9.7 deg in roll and + or - 9.3 deg in pitch, about + or - 6 deg in yaw, and + or - 15 cm in vertical translation. The unique vertical free flight freedom enables study of liftoffs and landings with power conditions duplicated. The response on the stand agrees well with that measured in free hovering flight, and pilot comments confirm this.

  20. Small Aircraft Transportation System Higher Volume Operations Concept

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Jones, Kenneth M.; Adams, Catherine A.

    2006-01-01

    This document defines the Small Aircraft Transportation System (SATS) Higher Volume Operations concept. The general philosophy underlying this concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. This document also provides details for a number of off-nominal and emergency procedures which address situations that could be expected to occur in a future SCA. The details for this operational concept along with a description of candidate aircraft systems to support this concept are provided.

  1. SCA Waveform Development for Space Telemetry

    NASA Technical Reports Server (NTRS)

    Mortensen, Dale J.; Kifle, Multi; Hall, C. Steve; Quinn, Todd M.

    2004-01-01

    The NASA Glenn Research Center is investigating and developing suitable reconfigurable radio architectures for future NASA missions. This effort is examining software-based open-architectures for space based transceivers, as well as common hardware platform architectures. The Joint Tactical Radio System's (JTRS) Software Communications Architecture (SCA) is a candidate for the software approach, but may need modifications or adaptations for use in space. An in-house SCA compliant waveform development focuses on increasing understanding of software defined radio architectures and more specifically the JTRS SCA. Space requirements put a premium on size, mass, and power. This waveform development effort is key to evaluating tradeoffs with the SCA for space applications. Existing NASA telemetry links, as well as Space Exploration Initiative scenarios, are the basis for defining the waveform requirements. Modeling and simulations are being developed to determine signal processing requirements associated with a waveform and a mission-specific computational burden. Implementation of the waveform on a laboratory software defined radio platform is proceeding in an iterative fashion. Parallel top-down and bottom-up design approaches are employed.

  2. An Umbrella for Three: The Unity of SCA.

    ERIC Educational Resources Information Center

    Bacon, Wallace A.

    This paper discusses the unity of the Speech Communication Association (SCA). To keep the SCA from fragmenting further into isolated factions, the paper urges SCA members to maintain an awareness of their common goals within the broad context of the term "communication," to interact with one another in the research and study of not only…

  3. Different mechanism of vocal cord paralysis between spinocerebellar ataxia (SCA 1 and SCA 3) and multiple system atrophy.

    PubMed

    Isozaki, Eiji; Naito, Rie; Kanda, Takemasa; Mizutani, Toshio; Hirai, Shunsaku

    2002-05-15

    While multiple system atrophy (MSA) is frequently associated with vocal cord paralysis (VCP) causing severe respiratory failure, it is still unknown whether hereditary types of spinocerebellar degeneration develop similar laryngeal paralysis. We analyzed the laryngeal function from the viewpoints of fiberoptic laryngoscopy and laryngeal myopathology and then attempted to clarify the difference of the mechanism of VCP among the patients with spinocerebellar ataxia type 1 (SCA 1), type 3 (SCA 3), and MSA. Seven patients with SCA 1, nineteen with SCA 3, and eleven with MSA were studied. Vocal cord movement was analyzed by fiberoptic laryngoscopy during wakefulness and diazepam-induced sleep (sleep load test). Paraffin-embedded sections or cryosections of the intrinsic laryngeal muscles from five autopsied cases (one with SCA 1 and four with SCA 3) were histologically examined. VCP was found in two of the seven SCA 1 patients (29%), three of the nineteen SCA 3 patients (16%), and in nine of the eleven MSA patients (82%). VCP observed in SCA 1 and SCA 3 was various in the severity and showed no exacerbation on sleep load test in all of the eight patients but one SCA 3 patient. In this patient, the findings of fiberoptic laryngoscopy were quite similar to those found in MSA. All the intrinsic laryngeal muscles including cricothyroid (CT), interarytenoid (IA), and posterior cricoarytenoid (PCA) muscles showed neurogenic atrophy in one autopsied SCA 1 and four SCA 3 patients. Our conclusion is that VCP in SCA 1 and SCA 3 contrasts with that in MSA in its occurrence, response to the sleep load test, and the distribution of the neurogenic abnormalities among the intrinsic laryngeal muscles. PMID:11997064

  4. Strategic Adaptation of SCA for STRS

    NASA Technical Reports Server (NTRS)

    Quinn, Todd; Kacpura, Thomas

    2007-01-01

    The Space Telecommunication Radio System (STRS) architecture is being developed to provide a standard framework for future NASA space radios with greater degrees of interoperability and flexibility to meet new mission requirements. The space environment imposes unique operational requirements with restrictive size, weight, and power constraints that are significantly smaller than terrestrial-based military communication systems. With the harsh radiation environment of space, the computing and processing resources are typically one or two generations behind current terrestrial technologies. Despite these differences, there are elements of the SCA that can be adapted to facilitate the design and implementation of the STRS architecture.

  5. Cytoplasmic and nuclear polyglutamine aggregates in SCA6 Purkinje cells.

    PubMed

    Ishikawa, K; Owada, K; Ishida, K; Fujigasaki, H; Shun Li, M; Tsunemi, T; Ohkoshi, N; Toru, S; Mizutani, T; Hayashi, M; Arai, N; Hasegawa, K; Kawanami, T; Kato, T; Makifuchi, T; Shoji, S; Tanabe, T; Mizusawa, H

    2001-06-26

    Aggregations of the alpha1A-calcium channel protein have been previously demonstrated in spinocerebellar ataxia type 6 (SCA6). Here the authors show that small aggregates, labeled by a monoclonal antibody 1C2 that preferentially detects expanded polyglutamine larger than that in SCA6 mutation, are present mainly in the cytoplasm but also in the nucleus of Purkinje cells. Although the length of expansion is small in SCA6, the current finding might indicate that SCA6 conforms to the pathogenic mechanism(s) in other polyglutamine diseases. PMID:11425948

  6. EPICS SCA CLIENTS ON THE .NET X64 PLATFORM

    SciTech Connect

    Timossi, Chris; Nishimura, Hiroshi

    2006-10-19

    We have developed a .NET assembly, which we call SCA.NET,which we have been using for building EPICS based control roomapplications at the Advanced Light Source (ALS). In this paper we reporton our experiences building a 64-bit version of SCA.NET and theunderlying channel access libraries for Windows XP x64 (using a dual coreAMD Athlon CPU). We also report on our progress in building newaccelerator control applications for this environment.

  7. Evidence suggesting possible SCA1 gene involvement in schizophrenia

    SciTech Connect

    Diehl, S.R.; Wange, S.; Sun, C.

    1994-09-01

    Several findings suggest a possible role for the SCA1 gene on chromosome 6p in some cases of schizophrenia. First, linkage analyses in Irish pedigrees provided LOD scores up to 3.0 for one model tested using microsatellites closely linked to SCA1. Reanalysis of these data using affected sibpair methods yielded a significant result (p = 0.01) for one marker. An attempt to replicate this linkage finding was made using 44 NIMH families (206 individuals, 80 affected) and 12 Utah families (120 individuals, 49 affected). LOD scores were negative in these new families, even allowing for heterogeneity, as were results using affected sibpair methods. However, one Utah family provided a LOD score of 1.3. We also screened the SCA1 trinucleotide repeat to search for expansions characteristic of this disorder in these families and in 38 additional unrelated schizophrenics. We found 1 schizophrenic with 41 repeats, which is substantially larger than the maximum size of 36 repeats observed in previous studies of several hundred controls. We are now assessing whether the distribution of SCA1 repeats differs significantly in schizophrenia versus controls. Recent reports suggest possible anticipation in schizophrenia (also characteristic of SCA1) and a few cases of psychiatric symptoms suggesting schizophrenia have been observed in the highly related disorder DRPLA (SCA2), which is also based on trinucleotide repeat expansion. These findings suggest that further investigations of this gene and chromosome region may be a priority.

  8. Shuttle Columbia Mated to 747 SCA with Crew

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The crew of NASA's 747 Shuttle Carrier Aircraft (SCA), seen mated with the Space Shuttle Columbia behind them, are from viewers left: Tom McMurtry, pilot; Vic Horton, flight engineer; Fitz Fulton, command pilot; and Ray Young, flight engineer. The SCA is used to ferry the shuttle between California and the Kennedy Space Center, Florida, and other destinations where ground transportation is not practical. The NASA 747 has special support struts atop the fuselage and internal strengthening to accommodate the additional weight of the orbiters. Small vertical fins have also been added to the tips of the horizontal stabilizers for additional stability due to air turbulence on the control surfaces caused by the orbiters. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the

  9. Lightning protection of aircraft

    NASA Technical Reports Server (NTRS)

    Fisher, F. A.; Plumer, J. A.

    1977-01-01

    The current knowledge concerning potential lightning effects on aircraft and the means that are available to designers and operators to protect against these effects are summarized. The increased use of nonmetallic materials in the structure of aircraft and the constant trend toward using electronic equipment to handle flight-critical control and navigation functions have served as impetus for this study.

  10. Design and Testing of Space Telemetry SCA Waveform

    NASA Technical Reports Server (NTRS)

    Mortensen, Dale J.; Handler, Louis M.; Quinn, Todd M.

    2006-01-01

    A Software Communications Architecture (SCA) Waveform for space telemetry is being developed at the NASA Glenn Research Center (GRC). The space telemetry waveform is implemented in a laboratory testbed consisting of general purpose processors, field programmable gate arrays (FPGAs), analog-to-digital converters (ADCs), and digital-to-analog converters (DACs). The radio hardware is integrated with an SCA Core Framework and other software development tools. The waveform design is described from both the bottom-up signal processing and top-down software component perspectives. Simulations and model-based design techniques used for signal processing subsystems are presented. Testing with legacy hardware-based modems verifies proper design implementation and dynamic waveform operations. The waveform development is part of an effort by NASA to define an open architecture for space based reconfigurable transceivers. Use of the SCA as a reference has increased understanding of software defined radio architectures. However, since space requirements put a premium on size, mass, and power, the SCA may be impractical for today s space ready technology. Specific requirements for an SCA waveform and other lessons learned from this development are discussed.

  11. scaRNAs regulate splicing and vertebrate heart development.

    PubMed

    Patil, Prakash; Kibiryeva, Nataliya; Uechi, Tamayo; Marshall, Jennifer; O'Brien, James E; Artman, Michael; Kenmochi, Naoya; Bittel, Douglas C

    2015-08-01

    Alternative splicing (AS) plays an important role in regulating mammalian heart development, but a link between misregulated splicing and congenital heart defects (CHDs) has not been shown. We reported that more than 50% of genes associated with heart development were alternatively spliced in the right ventricle (RV) of infants with tetralogy of Fallot (TOF). Moreover, there was a significant decrease in the level of 12 small cajal body-specific RNAs (scaRNAs) that direct the biochemical modification of specific nucleotides in spliceosomal RNAs. We sought to determine if scaRNA levels influence patterns of AS and heart development. We used primary cells derived from the RV of infants with TOF to show a direct link between scaRNA levels and splice isoforms of several genes that regulate heart development (e.g., GATA4, NOTCH2, DAAM1, DICER1, MBNL1 and MBNL2). In addition, we used antisense morpholinos to knock down the expression of two scaRNAs (scarna1 and snord94) in zebrafish and saw a corresponding disruption of heart development with an accompanying alteration in splice isoforms of cardiac regulatory genes. Based on these combined results, we hypothesize that scaRNA modification of spliceosomal RNAs assists in fine tuning the spliceosome for dynamic selection of mRNA splice isoforms. Our results are consistent with disruption of splicing patterns during early embryonic development leading to insufficient communication between the first and second heart fields, resulting in conotruncal misalignment and TOF. Our findings represent a new paradigm for determining the mechanisms underlying congenital cardiac malformations. PMID:25916634

  12. Shuttle Discovery Mated to 747 SCA

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The Space Shuttle Discovery rides atop '905,' NASA's 747 Shuttle Carrier Aircraft, on its delivery flight from California to the Kennedy Space Center, Florida, where it was prepared for its first orbital mission for 30 August to 5 September 1984. The NASA 747, obtained in 1974, has special support struts atop the fuselage and internal strengthening to accommodate the additional weight of the orbiters. Small vertical fins have also been added to the tips of the horizontal stabilizers for additional stability due to air turbulence on the control surfaces caused by the orbiters. A second modified 747, no. 911, went in to service in November 1990 and is also used to ferry orbiters to destinations where ground transportation is not practical. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the

  13. Small Aircraft Transportation System, Higher Volume Operations Concept: Off-Nominal Operations

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Conway, Sheila R.

    2005-01-01

    This document expands the Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept to include off-nominal conditions. The general philosophy underlying the HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). During periods of poor weather, a block of airspace would be established around designated non-towered, non-radar airports. Aircraft flying enroute to a SATS airport would be on a standard instrument flight rules flight clearance with Air Traffic Control providing separation services. Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Previous work developed the procedures for normal HVO operations. This document provides details for off-nominal and emergency procedures for situations that could be expected to occur in a future SCA.

  14. Sca-1 expression is required for efficient remodeling of the extracellular matrix during skeletal muscle regeneration

    PubMed Central

    Kafadar, Kimberly A.; Yi, Lin; Ahmad, Yusra; So, Leslie; Rossi, Fabio; Pavlath, Grace K.

    2009-01-01

    Sca-1 (Stem Cell Antigen-1) is a member of the Ly-6 family proteins that functions in cell growth, differentiation, and self-renewal in multiple tissues. In skeletal muscle Sca-1 negatively regulates myoblast proliferation and differentiation, and may function in the maintenance of progenitor cells. We investigated the role of Sca-1 in skeletal muscle regeneration and show here that Sca-1 expression is upregulated in a subset of myogenic cells upon muscle injury. We demonstrate that extract from crushed muscle upregulates Sca-1 expression in myoblasts in vitro, and that this effect is reversible and independent of cell proliferation. Sca-1-/- mice exhibit defects in muscle regeneration, with the development of fibrosis following injury. Sca-1-/- muscle displays reduced activity of matrix metalloproteinases, critical regulators of extracellular matrix remodeling. Interestingly, we show that the number of satellite cells is similar in wild-type and Sca-1-/- muscle, suggesting that in satellite cells Sca-1 does not play a role in self-renewal. We hypothesize that Sca-1 upregulates, directly or indirectly, the activity of matrix metalloproteinases, leading to matrix breakdown and efficient muscle regeneration. Further elucidation of the role of Sca-1 in matrix remodeling may aid in the development of novel therapeutic strategies for the treatment of fibrotic diseases. PMID:19059231

  15. Hypersonic reconnaissance aircraft

    NASA Technical Reports Server (NTRS)

    Bulk, Tim; Chiarini, David; Hill, Kevin; Kunszt, Bob; Odgen, Chris; Truong, Bon

    1992-01-01

    A conceptual design of a hypersonic reconnaissance aircraft for the U.S. Navy is discussed. After eighteen weeks of work, a waverider design powered by two augmented turbofans was chosen. The aircraft was designed to be based on an aircraft carrier and to cruise 6,000 nautical miles at Mach 4;80,000 feet and above. As a result the size of the aircraft was only allowed to have a length of eighty feet, fifty-two feet in wingspan, and roughly 2,300 square feet in planform area. Since this is a mainly cruise aircraft, sixty percent of its 100,000 pound take-off weight is JP fuel. At cruise, the highest temperature that it will encounter is roughly 1,100 F, which can be handled through the use of a passive cooling system.

  16. The influence of handling qualities on safety and survivability

    NASA Technical Reports Server (NTRS)

    Anderson, S. B.

    1977-01-01

    The relationship of handling qualities to safety and survivability of military aircraft is examined which includes the following: (1) a brief discussion of the philosophy used in the military specifications for treatment of degraded handling qualities, (2) an examination of several example handling qualities problem areas which influence safety and survivability; and (3) a movie illustrating the potential dangers of inadequate handling qualities features.

  17. The Characterization and Structure of the Manganese-responsive Transcriptional Regulator ScaR†§

    PubMed Central

    Stoll, Kate E.; Draper, William E.; Kliegman, Joseph I.; Golynskiy, Misha V.; Brew-Appiah, Rhoda A. T.; Phillips, Rebecca K.; Brown, Hattie K.; Breyer, Wendy A.; Jakubovics, Nicholas S.; Jenkinson, Howard F.; Brennan, Richard G.; Cohen, Seth M.; Glasfeld, Arthur

    2013-01-01

    The streptococcal coaggregation regulator (ScaR) of Streptococcus gordonii is a manganese-dependent transcriptional regulator. When intracellular manganese concentrations become elevated, ScaR represses transcription of the scaCBA operon, which encodes a manganese uptake transporter. A member of the DtxR/MntR family of metalloregulators, ScaR shares sequence similarity with other family members, and many metal-binding residues are conserved. Here, we show that ScaR is an active dimer, with two dimers binding the 46-bp scaC operator. Each ScaR subunit binds two manganese ions, and the protein is activated by a variety of other metal ions, including Cd2+, Co2+ and Ni2+, but not Zn2+. The crystal structure of apo-ScaR reveals a tertiary and quaternary structure similar to its homolog, the iron-responsive regulator DtxR. While each DtxR subunit binds a metal ion in two sites, labeled primary and ancillary, crystal structures of ScaR determined in the presence of Cd2+ and Zn2+ show only a single occupied metal binding site that is novel to ScaR. The site analogous to the primary site in DtxR is unoccupied, and the ancillary site is absent from ScaR. Instead, metal ions bind to ScaR at a site labeled “secondary”, which is composed of Glu80, Cys123, His125 and Asp160 and lies roughly 5 Å away from where the ancillary site would be predicted to exist. This difference suggests that ScaR and its closely related homologs are activated by a mechanism distinct from that of either DtxR or MntR. PMID:19795834

  18. Shuttle Enterprise Mated to 747 SCA in Flight

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The Space Shuttle Enterprise, the nation's prototype space shuttle orbiter, departed NASA's Dryden Flight Research Center, Edwards, California, at 11:00 a.m., 16 May 1983, on the first leg of its trek to the Paris Air Show at Le Bourget Airport, Paris, France. Carried by the huge 747 Shuttle Carrier Aircraft (SCA), the first stop for the Enterprise was Peterson AFB, Colorado Springs, Colorado. Piloting the 747 on the Europe trip were Joe Algranti, Johnson Space Center Chief Pilot, Astronaut Dick Scobee, and NASA Dryden Chief Pilot Tom McMurtry. Flight engineers for that portion of the flight were Dryden's Ray Young and Johnson Space Center's Skip Guidry. The Enterprise, named after the spacecraft of Star Trek fame, was originally carried and launched by the 747 during the Approach and Landing Tests (ALT) at Dryden Flight Research Center. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused

  19. STS-64 and 747-SCA Ferry Flight Takeoff

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Space Shuttle Discovery, mated to NASA's 747 Shuttle Carrier Aircraft (SCA), takes to the air for its ferry flight back to the Kennedy Space Center in Florida. The spacecraft, with a crew of six, was launched into a 57-degree high inclination orbit from the Kennedy Space Center, Florida, at 3:23 p.m., 9 September 1994. The mission featured the study of clouds and the atmosphere with a laser beaming system called Lidar In-Space Technology Experiment (LITE), and the first untethered space walk in ten years. A Spartan satellite was also deployed and later retrieved in the study of the sun's corona and solar wind. The mission was scheduled to end Sunday, 18 September, but was extended one day to continue science work. Bad weather at the Kennedy Space Center on 19 September, forced a one-day delay to September 20, with a weather divert that day to Edwards. Mission commander was Richard Richards, the pilot Blaine Hammond, while mission specialists were Jerry Linenger, Susan Helms, Carl Meade, and Mark Lee. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders

  20. Shuttle Enterprise Mated to 747 SCA in Flight

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The Space Shuttle Enterprise, the nation's prototype space shuttle orbiter, departed NASA's Dryden Flight Research Center, Edwards, California, at 11:00 a.m., 16 May 1983, on the first leg of its trek to the Paris Air Show at Le Bourget Airport, Paris, France. Carried by the huge 747 Shuttle Carrier Aircraft (SCA), the first stop for the Enterprise was Peterson AFB, Colorado Springs, Colorado. Piloting the 747 on the Europe trip were Joe Algranti, Johnson Space Center Chief Pilot, Astronaut Dick Scobee, and NASA Dryden Chief Pilot Tom McMurtry. Flight engineers for that portion of the flight were Dryden's Ray Young and Johnson Space Center's Skip Guidry. The Enterprise, named after the spacecraft of Star Trek fame, was originally carried and launched by the 747 during the Approach and Landing Tests (ALT) at Dryden Flight Research Center. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused

  1. Shuttle Enterprise Mated to 747 SCA on Ramp

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The Space Shuttle Enterprise, the nation's prototype space shuttle orbiter, before departing NASA's Dryden Flight Research Center, Edwards, California, at 11:00 a.m., 16 May 1983, on the first leg of its trek to the Paris Air Show at Le Bourget Airport, Paris, France. Seen here atop the huge 747 Shuttle Carrier Aircraft (SCA), the first stop for the Enterprise was Peterson AFB, Colorado Springs, Colorado. Piloting the 747 on the Europe trip were Joe Algranti, Johnson Space Center Chief Pilot, Astronaut Dick Scobee, and NASA Dryden Chief Pilot Tom McMurtry. Flight engineers for that portion of the flight were Dryden's Ray Young and Johnson Space Center's Skip Guidry. The Enterprise, named after the spacecraft of Star Trek fame, was originally carried and launched by the 747 during the Approach and Landing Tests (ALT) at Dryden Flight Research Center. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be

  2. STS-64 and 747-SCA Ferry Flight Takeoff

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Space Shuttle Discovery, mated to NASA's 747 Shuttle Carrier Aircraft (SCA), takes to the air for its ferry flight back to the Kennedy Space Center in Florida. The spacecraft, with a crew of six, was launched into a 57-degree high inclination orbit from the Kennedy Space Center, Florida, at 3:23 p.m., 9 September 1994. The mission featured the study of clouds and the atmosphere with a laser beaming system called Lidar In-Space Technology Experiment (LITE), and the first untethered space walk in ten years. A Spartan satellite was also deployed and later retrieved in the study of the sun's corona and solar wind. The mission was scheduled to end Sunday, 18 September, but was extended one day to continue science work. Bad weather at the Kennedy Space Center on 19 September, forced a one-day delay to September 20, with a weather divert that day to Edwards. Mission commander was Richard Richards, the pilot Blaine Hammond, while mission specialists were Jerry Linenger, Susan Helms, Carl Meade, and Mark Lee. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders

  3. Differentiation-Associated MicroRNA Alterations in Mouse Heart-Derived Sca-1+CD31− and Sca-1+CD31+ Cells

    PubMed Central

    Wu, Qiong; Zhan, Jinxi; Li, Yun; Wang, Xiaoxia; Xu, Lu; Yu, Juan; Pu, Shiming; Zhou, Zuping

    2016-01-01

    Cardiac resident stem/progenitor cells (CSC/CPCs) are critical to the cellular and functional integrity of the heart because they maintain myocardial cell homeostasis. Several populations of CSC/CPCs have been identified based on expression of different stem cell-associated antigens. Sca-1+ cells in the cardiac tissue may be the most common CSC/CPCs. However, they are a heterogeneous cell population and, in transplants, clinicians might transplant more endothelial cells, cardiomyocytes, or other cells than stem cells. The purposes of this study were to (1) isolate CSC/CPCs with Lin−CD45−Sca-1+CD31− and Lin−CD45−Sca-1+CD31+ surface antigens using flow-activated cell sorting; (2) investigate their differentiation potential; and (3) determine the molecular basis for differences in stemness characteristics between cell subtypes. The results indicated that mouse heart-derived Sca-1+CD31− cells were multipotent and retained the ability to differentiate into different cardiac cell lineages, but Sca-1+CD31+ cells did not. Integrated analysis of microRNA and mRNA expression indicated that 20 microRNAs and 49 mRNAs were inversely associated with Sca-1+CD31− and Sca-1+CD31+ subtype stemness characteristics. In particular, mmu-miR-322-5p had more targeted and inversely associated genes and transcription factors and might have higher potential for CSC/CPCs differentiation. PMID:27298624

  4. REM behavior disorder and excessive daytime somnolence in Machado-Joseph disease (SCA-3).

    PubMed

    Friedman, Joseph H; Fernandez, Hubert H; Sudarsky, Lewis R

    2003-12-01

    We reported previously that behavior suggestive of rapid eye movement sleep behavior disorder (RBD) was markedly increased in a small population of SCA-3 patients. We, therefore, asked patients and nonpatient attendees at an SCA-3 annual clinic to complete a questionnaire soliciting RBD-like behavior. Our results support the previous observation that RBD-like behaviors are significantly increased in SCA-3. PMID:14673890

  5. Low Temperature Plasma Kills SCaBER Cancer Cells

    NASA Astrophysics Data System (ADS)

    Barekzi, Nazir; van Way, Lucas; Laroussi, Mounir

    2013-09-01

    Squamous cell carcinoma of the bladder is a rare type of bladder cancer that forms as a result of chronic irritation of the epithelial lining of the bladder. The cell line used in this study is SCaBER (ATCC® HTB-3™) derived from squamous cell carcinoma of the human urinary bladder. Current treatments of bladder cancer include surgery, radiation and chemotherapy. However, the cost of these treatments, the potential toxicity of the chemotherapeutic agents and the systemic side-effects warrant an alternative to current cancer treatment. This paper represents preliminary studies to determine the effects of biologically tolerant plasma (BTP) on a cell line of human bladder cancer cells. Previous work by our group using the plasma pencil revealed the efficacy of BTP on leukemia cells suspended in solution. Based on these earlier findings we hypothesized that the plasma exposure would elicit a similar programmed cell death in the SCaBER cells. Trypan blue exclusion and MTT assays revealed the cell killing after exposure to BTP. Our study indicates that low temperature plasma generated by ionizing helium gas and the reactive species may be a suitable and safe alternative for cancer therapy.

  6. A Service Portal for the Integrated SCaN Network

    NASA Technical Reports Server (NTRS)

    Marx, Sarah R.

    2012-01-01

    The Space Communication and Navigation (SCaN) program office owns the assets and services provided by the Deep Space Network (DSN), Near Earth Network (NEN), and Space Network (SN). At present, these individual networks are operated by different NASA centers--JPL for DSN--and Goddard Space Flight Center (GSFC) for NEN and SN--with separate commitments offices for each center. In the near future, SCaN's program office would like to deploy an integrated service portal which would merge the two commitments offices with the goal of easing the task of user planning for space missions requiring services of two or more of these networks. Following interviews with subject matter experts in this field, use cases were created to include the services and functionality mission users would like to see in this new integrated service portal. These use cases provide a guideline for a mock-up of the design of the user interface for the portal. The benefit of this work will ease the time required and streamline/standardize the process for planning and scheduling SCAN's services for future space missions.

  7. The Rickettsia conorii Autotransporter Protein Sca1 Promotes Adherence to Nonphagocytic Mammalian Cells ▿ †

    PubMed Central

    Riley, Sean P.; Goh, Kenneth C.; Hermanas, Timothy M.; Cardwell, Marissa M.; Chan, Yvonne G. Y.; Martinez, Juan J.

    2010-01-01

    The pathogenesis of spotted fever group (SFG) Rickettsia species, including R. conorii and R. rickettsii, is acutely dependent on adherence to and invasion of host cells, including cells of the mammalian endothelial system. Bioinformatic analyses of several rickettsia genomes revealed the presence of a cohort of genes designated sca genes that are predicted to encode proteins with homology to autotransporter proteins of Gram-negative bacteria. Previous work demonstrated that three members of this family, rOmpA (Sca0), Sca2, and rOmpB (Sca5) are involved in the interaction with mammalian cells; however, very little was known about the function of other conserved rickettsial Sca proteins. Here we demonstrate that sca1, a gene present in nearly all SFG rickettsia genomes, is actively transcribed and expressed in R. conorii cells. Alignment of Sca1 sequences from geographically diverse SFG Rickettsia species showed that there are high degrees of sequence identity and conservation of these sequences, suggesting that Sca1 may have a conserved function. Using a heterologous expression system, we demonstrated that production of R. conorii Sca1 in the Escherichia coli outer membrane is sufficient to mediate attachment to but not invasion of a panel of cultured mammalian epithelial and endothelial cells. Furthermore, preincubation of a recombinant Sca1 peptide with host cells blocked R. conorii cell association. Together, these results demonstrate that attachment to mammalian cells can be uncoupled from the entry process and that Sca1 is involved in the adherence of R. conorii to host cells. PMID:20176791

  8. Final Ferry Takes SCA-Endeavour Over Los Angeles

    NASA Video Gallery

    Space shuttle Endeavour atop NASA's Shuttle Carrier Aircraft overflew many landmarks in Los Angeles to conclude its final ferry flight into history on Sept. 21, 2012. Among highlights in this video...

  9. Gene, Stem Cell, and Alternative Therapies for SCA 1

    PubMed Central

    Wagner, Jacob L.; O'Connor, Deirdre M.; Donsante, Anthony; Boulis, Nicholas M.

    2016-01-01

    Spinocerebellar ataxia 1 is an autosomal dominant disease characterized by neurodegeneration and motor dysfunction. In disease pathogenesis, polyglutamine expansion within Ataxin-1, a gene involved in transcriptional repression, causes protein nuclear inclusions to form. Most notably, neuronal dysfunction presents in Purkinje cells. However, the effect of mutant Ataxin-1 is not entirely understood. Two mouse models are employed to represent spinocerebellar ataxia 1, a B05 transgenic model that specifically expresses mutant Ataxin-1 in Purkinje cells, and a Sca1 154Q/2Q model that inserts the polyglutamine expansion into the mouse Ataxin-1 locus so that the mutant Ataxin-1 is expressed in all cells that express Ataxin-1. This review aims to summarize and evaluate the wide variety of therapies proposed for spinocerebellar ataxia 1, specifically gene and stem cell therapies. PMID:27570504

  10. Gene, Stem Cell, and Alternative Therapies for SCA 1.

    PubMed

    Wagner, Jacob L; O'Connor, Deirdre M; Donsante, Anthony; Boulis, Nicholas M

    2016-01-01

    Spinocerebellar ataxia 1 is an autosomal dominant disease characterized by neurodegeneration and motor dysfunction. In disease pathogenesis, polyglutamine expansion within Ataxin-1, a gene involved in transcriptional repression, causes protein nuclear inclusions to form. Most notably, neuronal dysfunction presents in Purkinje cells. However, the effect of mutant Ataxin-1 is not entirely understood. Two mouse models are employed to represent spinocerebellar ataxia 1, a B05 transgenic model that specifically expresses mutant Ataxin-1 in Purkinje cells, and a Sca1 154Q/2Q model that inserts the polyglutamine expansion into the mouse Ataxin-1 locus so that the mutant Ataxin-1 is expressed in all cells that express Ataxin-1. This review aims to summarize and evaluate the wide variety of therapies proposed for spinocerebellar ataxia 1, specifically gene and stem cell therapies. PMID:27570504

  11. JTRS/SCA and Custom/SDR Waveform Comparison

    NASA Technical Reports Server (NTRS)

    Oldham, Daniel R.; Scardelletti, Maximilian C.

    2007-01-01

    This paper compares two waveform implementations generating the same RF signal using the same SDR development system. Both waveforms implement a satellite modem using QPSK modulation at 1M BPS data rates with one half rate convolutional encoding. Both waveforms are partitioned the same across the general purpose processor (GPP) and the field programmable gate array (FPGA). Both waveforms implement the same equivalent set of radio functions on the GPP and FPGA. The GPP implements the majority of the radio functions and the FPGA implements the final digital RF modulator stage. One waveform is implemented directly on the SDR development system and the second waveform is implemented using the JTRS/SCA model. This paper contrasts the amount of resources to implement both waveforms and demonstrates the importance of waveform partitioning across the SDR development system.

  12. Proteolytic cleavage of ataxin-7 promotes SCA7 retinal degeneration and neurological dysfunction.

    PubMed

    Guyenet, Stephan J; Mookerjee, Shona S; Lin, Amy; Custer, Sara K; Chen, Sylvia F; Sopher, Bryce L; La Spada, Albert R; Ellerby, Lisa M

    2015-07-15

    The neurodegenerative disorder spinocerebellar ataxia type 7 (SCA7) is caused by a polyglutamine (polyQ) expansion in the ataxin-7 protein, categorizing SCA7 as one member of a large class of heritable neurodegenerative proteinopathies. Cleavage of ataxin-7 by the protease caspase-7 has been demonstrated in vitro, and the accumulation of proteolytic cleavage products in SCA7 patients and mouse models has been identified as an early pathological change. However, it remains unknown whether a causal relationship exists between ataxin-7 proteolysis and in vivo SCA7 disease progression. To determine whether caspase cleavage is a critical event in SCA7 disease pathogenesis, we generated transgenic mice expressing polyQ-expanded ataxin-7 with a second-site mutation (D266N) to prevent caspase-7 proteolysis. When we compared SCA7-D266N mice with SCA7 mice lacking the D266N mutation, we found that SCA7-D266N mice exhibited improved motor performance, reduced neurodegeneration and substantial lifespan extension. Our findings indicate that proteolysis at the D266 caspase-7 cleavage site is an important mediator of ataxin-7 neurotoxicity, suggesting that inhibition of caspase-7 cleavage of polyQ-ataxin-7 may be a promising therapeutic strategy for this untreatable disorder. PMID:25859008

  13. Cajal Body Proteins Differentially Affect the Processing of Box C/D scaRNPs

    PubMed Central

    Enwerem, Isioma I.; Wu, Guowei; Yu, Yi Tao; Hebert, Michael D.

    2015-01-01

    Small nuclear ribonucleoproteins (snRNPs), which are required for pre-mRNA splicing, contain extensively modified snRNA. Small Cajal body-specific ribonucleoproteins (scaRNPs) mediate these modifications. It is unknown how the box C/D class of scaRNPs localizes to Cajal Bodies (CBs). The processing of box C/D scaRNA is also unclear. Here, we explore the processing of box C/D scaRNA 2 and 9 by coilin. We also broaden our investigation to include WRAP53 and SMN, which accumulate in CBs, play a role in RNP biogenesis and associate with coilin. These studies demonstrate that the processing of an ectopically expressed scaRNA2 is altered upon the reduction of coilin, WRAP53 or SMN, but the extent and direction of this change varies depending on the protein reduced. We also show that box C/D scaRNP activity is reduced in a cell line derived from coilin knockout mice. Collectively, the findings presented here further implicate coilin as being a direct participant in the formation of box C/D scaRNPs, and demonstrate that WRAP53 and SMN may also play a role, but the activity of these proteins is divergent to coilin. PMID:25875178

  14. STRS Radio Service Software for NASA's SCaN Testbed

    NASA Technical Reports Server (NTRS)

    Mortensen, Dale J.; Bishop, Daniel Wayne; Chelmins, David T.

    2013-01-01

    NASA's Space Communication and Navigation(SCaN) Testbed was launched to the International Space Station in 2012. The objective is to promote new software defined radio technologies and associated software application reuse, enabled by this first flight of NASA's Space Telecommunications Radio System (STRS) architecture standard. Pre-launch testing with the testbed's software defined radios was performed as part of system integration. Radio services for the JPL SDR were developed during system integration to allow the waveform application to operate properly in the space environment, especially considering thermal effects. These services include receiver gain control, frequency offset, IQ modulator balance, and transmit level control. Development, integration, and environmental testing of the radio services will be described. The added software allows the waveform application to operate properly in the space environment, and can be reused by future experimenters testing different waveform applications. Integrating such services with the platform provided STRS operating environment will attract more users, and these services are candidates for interface standardization via STRS.

  15. STRS Radio Service Software for NASA's SCaN Testbed

    NASA Technical Reports Server (NTRS)

    Mortensen, Dale J.; Bishop, Daniel Wayne; Chelmins, David T.

    2012-01-01

    NASAs Space Communication and Navigation(SCaN) Testbed was launched to the International Space Station in 2012. The objective is to promote new software defined radio technologies and associated software application reuse, enabled by this first flight of NASAs Space Telecommunications Radio System(STRS) architecture standard. Pre-launch testing with the testbeds software defined radios was performed as part of system integration. Radio services for the JPL SDR were developed during system integration to allow the waveform application to operate properly in the space environment, especially considering thermal effects. These services include receiver gain control, frequency offset, IQ modulator balance, and transmit level control. Development, integration, and environmental testing of the radio services will be described. The added software allows the waveform application to operate properly in the space environment, and can be reused by future experimenters testing different waveform applications. Integrating such services with the platform provided STRS operating environment will attract more users, and these services are candidates for interface standardization via STRS.

  16. V/STOL tilt rotor aircraft study. Volume 9: Piloted simulator evaluation of the Boeing Vertol model 222 tilt rotor aircraft

    NASA Technical Reports Server (NTRS)

    Rosenstein, H.; Mcveigh, M. A.; Mollenkof, P. A.

    1973-01-01

    The results of a real time piloted simulation to investigate the handling qualities and performance of a tilting rotor aircraft design are presented. The aerodynamic configuration of the aircraft is described. The procedures for conducting the simulator evaluation are reported. Pilot comments of the aircraft handling qualities under various simulated flight conditions are included. The time histories of selected pilot maneuvers are shown.

  17. The structural plasticity of SCA7 domains defines their differential nucleosome-binding properties

    PubMed Central

    Bonnet, Jacques; Wang, Ying-Hui; Spedale, Gianpiero; Atkinson, R Andrew; Romier, Christophe; Hamiche, Ali; Pijnappel, W W M Pim; Timmers, H Th Marc; Tora, László; Devys, Didier; Kieffer, Bruno

    2010-01-01

    SAGA (Spt–Ada–Gcn5 acetyltransferase), a coactivator complex involved in chromatin remodelling, harbours both histone acetylation and deubiquitination activities. ATXN7/Sgf73 and ATXN7L3, two subunits of the SAGA deubiquitination module, contain an SCA7 domain characterized by an atypical zinc-finger. We show that the yeast Sgf73–SCA7 domain is not required to recruit Sgf73 into SAGA. Instead, it binds to nucleosomes, a property that is conserved in the human ATXN7–SCA7 domain but is lost in the ATXN7L3 domain. The solution structures of the SCA7 domain of both ATXN7 and ATXN7L3 reveal a new, common zinc-finger motif at the heart of two distinct folds, providing a molecular basis for the observed functional differences. PMID:20634802

  18. Sca-1(+) mesenchymal stromal cells inhibit splenic marginal zone B lymphocytes commitment through Caspase-3.

    PubMed

    Chen, Yaozhen; Yang, Jialei; Zhang, Hui-Jie; Fan, Hong; An, Ning; Xin, Jiajia; Li, Na; Xu, Jinmei; Yin, Wen; Wu, Zhongliang; Hu, Xingbin

    2016-05-01

    Mesenchymal stromal cells (MSCs) have been characterized as an important component of hematopoietic niche, which are capable of modulating the immune system through interaction with a wide range of immune cells. Marginal zone B cells, one main type of mature B lymphocytes, play a central role in eliciting antibody response against pathogens. However, how MSCs and its subpopulations regulate marginal zone B cells commitment is unknown yet. In this study, we assessed the contribution of Sca-1(+) MSCs on marginal zone B cells commitment. Our results showed that Sca-1(+) MSCs inhibit the commitment of marginal zone B lymphocytes. The inhibition was exerted through lowered Caspase-3 expression. Furthermore, we found marginal zone B lymphocytes in spleen of Caspase-3 knockout mice decreased and Caspase-3 knockout Sca-1(+) MSCs accounted for the MZB lymphocytes decrease. In conclusion, our investigation provided clues about Sca-1(+) MSCs regulation on the commitment of marginal zone B cells through Caspase-3 gene. PMID:26861667

  19. Evaluation of SCaMPR Satellite QPEs for Operational Hydrologic Prediction

    NASA Astrophysics Data System (ADS)

    LEE, H.; Zhang, Y.; Seo, D.; Kitzmiller, D. H.; Kuligowski, R. J.; Corby, R.

    2011-12-01

    National Weather Service (NWS) River Forecast Centers (RFCs) use rain gauge or radar-gauge multi-sensor quantitative precipitation estimates (QPEs) as the primary rainfall input to their operational hydrologic models. In areas with poor radar and rain gauge coverage, satellite-based QPEs are a potential alternative. In this work, we evaluated the utility of satellite-based QPEs produced via the Self-Calibrating Multivariate Precipitation Retrieval (SCaMPR) algorithm for operational hydrologic modeling for a set of basins in Texas and Louisiana for the period of 2000-7. First, we assessed the relative accuracy of two sets of SCaMPR QPEs versus gauge-only QPE, with operational multi-sensor QPEs as the reference. One set used only operational polar orbiting satellite microwave input as the predictors, the other included Tropical Rainfall Measuring Mission (TRMM) rain rates in the calibration process. We then performed hydrologic simulations using these QPEs and evaluated the simulations. Results indicated that a) SCaMPR QPEs showed better/worse skill than the gauge-only QPEs in resolving heavy precipitation at 1-h/24-h time intervals in terms of Critical Success Index (CSI); b) SCaMPR QPEs underperformed gauge-only QPEs in simulating flood events; and c) ingesting TRMM rainfall rates helped enhance the hydrologic utility of SCaMPR QPE, by mitigating the positive bias of SCaMPR QPEs, elevating the detection rates of heavy rainfall, and improving the simulation of flood discharge. Our findings suggest that the superior performance of gauge-only QPEs versus SCaMPR in hydrologic simulations is tied to its better accuracy at 24-h scale. The implication of the scale dependence in the relative performance of SCaMPR QPEs to their potential hydrologic utility is discussed.

  20. DISCO-SCA and Properly Applied GSVD as Swinging Methods to Find Common and Distinctive Processes

    PubMed Central

    Van Deun, Katrijn; Van Mechelen, Iven; Thorrez, Lieven; Schouteden, Martijn; De Moor, Bart; van der Werf, Mariët J.; De Lathauwer, Lieven; Smilde, Age K.; Kiers, Henk A. L.

    2012-01-01

    Background In systems biology it is common to obtain for the same set of biological entities information from multiple sources. Examples include expression data for the same set of orthologous genes screened in different organisms and data on the same set of culture samples obtained with different high-throughput techniques. A major challenge is to find the important biological processes underlying the data and to disentangle therein processes common to all data sources and processes distinctive for a specific source. Recently, two promising simultaneous data integration methods have been proposed to attain this goal, namely generalized singular value decomposition (GSVD) and simultaneous component analysis with rotation to common and distinctive components (DISCO-SCA). Results Both theoretical analyses and applications to biologically relevant data show that: (1) straightforward applications of GSVD yield unsatisfactory results, (2) DISCO-SCA performs well, (3) provided proper pre-processing and algorithmic adaptations, GSVD reaches a performance level similar to that of DISCO-SCA, and (4) DISCO-SCA is directly generalizable to more than two data sources. The biological relevance of DISCO-SCA is illustrated with two applications. First, in a setting of comparative genomics, it is shown that DISCO-SCA recovers a common theme of cell cycle progression and a yeast-specific response to pheromones. The biological annotation was obtained by applying Gene Set Enrichment Analysis in an appropriate way. Second, in an application of DISCO-SCA to metabolomics data for Escherichia coli obtained with two different chemical analysis platforms, it is illustrated that the metabolites involved in some of the biological processes underlying the data are detected by one of the two platforms only; therefore, platforms for microbial metabolomics should be tailored to the biological question. Conclusions Both DISCO-SCA and properly applied GSVD are promising integrative methods for

  1. Impaired mTORC1-Dependent Expression of Homer-3 Influences SCA1 Pathophysiology.

    PubMed

    Ruegsegger, Céline; Stucki, David M; Steiner, Silvio; Angliker, Nico; Radecke, Julika; Keller, Eva; Zuber, Benoît; Rüegg, Markus A; Saxena, Smita

    2016-01-01

    Spinocerebellar ataxia type 1 (SCA1), due to the expansion of a polyglutamine repeat within the ubiquitously expressed Ataxin-1 protein, leads to the premature degeneration of Purkinje cells (PCs), the cause of which is poorly understood. Here, we identified the unique proteomic signature of Sca1(154Q/2Q) PCs at an early stage of disease, highlighting extensive alterations in proteins associated with synaptic functioning, maintenance, and transmission. Focusing on Homer-3, a PC-enriched scaffold protein regulating neuronal activity, revealed an early decline in its expression. Impaired climbing fiber-mediated synaptic transmission diminished mTORC1 signaling, paralleling Homer-3 reduction in Sca1(154Q/2Q) PCs. Ablating mTORC1 within PCs or pharmacological inhibition of mTORC1 identified Homer-3 as its downstream target. mTORC1 knockout in Sca1(154Q/2Q) PCs exacerbated and accelerated pathology. Reinstating Homer-3 expression in Sca1(154Q/2Q) PCs attenuated cellular dysfunctions and improved motor deficits. Our work reveals that impaired mTORC1-Homer-3 activity underlies PC susceptibility in SCA1 and presents a promising therapeutic target. PMID:26748090

  2. Handling qualities effects of display latency

    NASA Technical Reports Server (NTRS)

    King, David W.

    1993-01-01

    Display latency is the time delay between aircraft response and the corresponding response of the cockpit displays. Currently, there is no explicit specification for allowable display lags to ensure acceptable aircraft handling qualities in instrument flight conditions. This paper examines the handling qualities effects of display latency between 70 and 400 milliseconds for precision instrument flight tasks of the V-22 Tiltrotor aircraft. Display delay effects on the pilot control loop are analytically predicted through a second order pilot crossover model of the V-22 lateral axis, and handling qualities trends are evaluated through a series of fixed-base piloted simulation tests. The results show that the effects of display latency for flight path tracking tasks are driven by the stability characteristics of the attitude control loop. The data indicate that the loss of control damping due to latency can be simply predicted from knowledge of the aircraft's stability margins, control system lags, and required control bandwidths. Based on the relationship between attitude control damping and handling qualities ratings, latency design guidelines are presented. In addition, this paper presents a design philosophy, supported by simulation data, for using flight director display augmentation to suppress the effects of display latency for delays up to 300 milliseconds.

  3. Unexpanded and intermediate CAG polymorphisms at the SCA2 locus (ATXN2) in the Cuban population: evidence about the origin of expanded SCA2 alleles.

    PubMed

    Laffita-Mesa, José Miguel; Velázquez-Pérez, Luis C; Santos Falcón, Nieves; Cruz-Mariño, Tania; González Zaldívar, Yanetza; Vázquez Mojena, Yaimee; Almaguer-Gotay, Dennis; Almaguer Mederos, Luis Enrique; Rodríguez Labrada, Roberto

    2012-01-01

    The role of short, large or intermediate normal alleles (ANs) of the ataxin-2 gene in generating expanded alleles (EAs) causing spinocerebellar ataxia type 2 (SCA2) is poorly understood. It has been postulated that SCA2 prevalence is related to the frequency of large ANs. SCA2 shows the highest worldwide prevalence in Cuban population, which is therefore a unique source for studying the relationship between the frequency of large and intermediate alleles and the frequency of SCA2 mutation. Through genetic polymorphism analyses in a comprehensive sample (~3000 chromosomes), we show that the frequency of large ANs in the ataxin-2 gene is the highest worldwide, although short ANs are also frequent. This highly polymorphic population displayed also high variability in the CAG sequence, featured by loss of the anchor CAA interruption(s). In addition, large ANs showed germinal and somatic instability. Our study also includes related genotypic, genealogical and haplotypic data and provides substantial evidence with regard to the role of large and intermediate alleles in the generation of pathological EAs. PMID:21934711

  4. Unexpanded and intermediate CAG polymorphisms at the SCA2 locus (ATXN2) in the Cuban population: evidence about the origin of expanded SCA2 alleles

    PubMed Central

    Laffita-Mesa, José Miguel; Velázquez-Pérez, Luis C; Santos Falcón, Nieves; Cruz-Mariño, Tania; González Zaldívar, Yanetza; Vázquez Mojena, Yaimee; Almaguer-Gotay, Dennis; Almaguer Mederos, Luis Enrique; Rodríguez Labrada, Roberto

    2012-01-01

    The role of short, large or intermediate normal alleles (ANs) of the ataxin-2 gene in generating expanded alleles (EAs) causing spinocerebellar ataxia type 2 (SCA2) is poorly understood. It has been postulated that SCA2 prevalence is related to the frequency of large ANs. SCA2 shows the highest worldwide prevalence in Cuban population, which is therefore a unique source for studying the relationship between the frequency of large and intermediate alleles and the frequency of SCA2 mutation. Through genetic polymorphism analyses in a comprehensive sample (∼3000 chromosomes), we show that the frequency of large ANs in the ataxin-2 gene is the highest worldwide, although short ANs are also frequent. This highly polymorphic population displayed also high variability in the CAG sequence, featured by loss of the anchor CAA interruption(s). In addition, large ANs showed germinal and somatic instability. Our study also includes related genotypic, genealogical and haplotypic data and provides substantial evidence with regard to the role of large and intermediate alleles in the generation of pathological EAs. PMID:21934711

  5. Reversal of Ischemic Cardiomyopathy with Sca-1+ Stem Cells Modified with Multiple Growth Factors

    PubMed Central

    Li, Ning; Pasha, Zeeshan; Ashraf, Muhammad

    2014-01-01

    Background We hypothesized that bone marrow derived Sca-1+ stem cells (BM Sca-1+) transduced with multiple therapeutic cytokines with diverse effects will induce faster angiomyogenic differentiation in the infarcted myocardium. Methods and Results BM Sca-1+ were purified from transgenic male mice expressing GFP. Plasmids encoding for select quartet of growth factors, i.e., human IGF-1, VEGF, SDF-1α and HGF were prepared and used for genetic modification of Sca-1+ cells (GFSca-1+). Scramble transfected cells (ScSca-1+) were used as a control. RT-PCR and western blotting showed significantly higher expression of the growth factors in GFSca-1+. Besides the quartet of the therapeutic growth factors, PCR based growth factor array showed upregulation of multiple angiogenic and prosurvival factors such as Ang-1, Ang-2, MMP9, Cx43, BMP2, BMP5, FGF2, and NGF in GFSca-1+ (p<0.01 vs ScSca-1+). LDH and TUNEL assays showed enhanced survival of GFSca-1+ under lethal anoxia (p<0.01 vs ScSca-1+). MTS assay showed significant increased cell proliferation in GFSca-1+ (p<0.05 vs ScSca-1+). For in vivo study, female mice were grouped to receive the intramyocardial injection of 15 μl DMEM without cells (group-1) or containing 2.5×105 ScSca-1+ (group-2) or GFSca-1+ (group-3) immediately after coronary artery ligation. As indicated by Sry gene, a higher survival of GFSca-1+ in group-3 on day4 (2.3 fold higher vs group-2) was observed with massive mobilization of stem and progenitor cells (cKit+, Mdr1+, Cxcr4+ cells). Heart tissue sections immunostained for actinin and Cx43 at 4 weeks post engraftment showed extensive myofiber formation and expression of gap junctions. Immunostaining for vWF showed increased blood vessel density in both peri-infarct and infarct regions in group-3. Infarct size was attenuated and the global heart function was improved in group-3 as compared to group-2. Conclusions Administration of BM Sca-1+ transduced with multiple genes is a novel approach to treat

  6. Handling Qualities Implications for Crewed Spacecraft Operations

    NASA Technical Reports Server (NTRS)

    Bailey, Randall E.; Jackson, E. Bruce; Arthur, J. J.

    2012-01-01

    Abstract Handling qualities embody those qualities or characteristics of an aircraft that govern the ease and precision with which a pilot is able to perform the tasks required in support of an aircraft role. These same qualities are as critical, if not more so, in the operation of spacecraft. A research, development, test, and evaluation process was put into effect to identify, understand, and interpret the engineering and human factors principles which govern the pilot-vehicle dynamic system as they pertain to space exploration missions and tasks. Toward this objective, piloted simulations were conducted at the NASA Langley Research Center and Ames Research Center for earth-orbit proximity operations and docking and lunar landing. These works provide broad guidelines for the design of spacecraft to exhibit excellent handling characteristics. In particular, this work demonstrates how handling qualities include much more than just stability and control characteristics of a spacecraft or aircraft. Handling qualities are affected by all aspects of the pilot-vehicle dynamic system, including the motion, visual and aural cues of the vehicle response as the pilot performs the required operation or task. A holistic approach to spacecraft design, including the use of manual control, automatic control, and pilot intervention/supervision is described. The handling qualities implications of design decisions are demonstrated using these pilot-in-the-loop evaluations of docking operations and lunar landings.

  7. Aircraft Design

    NASA Technical Reports Server (NTRS)

    Bowers, Albion H. (Inventor); Uden, Edward (Inventor)

    2016-01-01

    The present invention is an aircraft wing design that creates a bell shaped span load, which results in a negative induced drag (induced thrust) on the outer portion of the wing; such a design obviates the need for rudder control of an aircraft.

  8. Aircraft Noise

    NASA Astrophysics Data System (ADS)

    Michel, Ulf; Dobrzynski, Werner; Splettstoesser, Wolf; Delfs, Jan; Isermann, Ullrich; Obermeier, Frank

    Aircraft industry is exposed to increasing public pressure aiming at a continuing reduction of aircraft noise levels. This is necessary to both compensate for the detrimental effect on noise of the expected increase in air traffic and improve the quality of living in residential areas around airports.

  9. Space Communications and Navigation (SCaN) Network Simulation Tool Development and Its Use Cases

    NASA Technical Reports Server (NTRS)

    Jennings, Esther; Borgen, Richard; Nguyen, Sam; Segui, John; Stoenescu, Tudor; Wang, Shin-Ywan; Woo, Simon; Barritt, Brian; Chevalier, Christine; Eddy, Wesley

    2009-01-01

    In this work, we focus on the development of a simulation tool to assist in analysis of current and future (proposed) network architectures for NASA. Specifically, the Space Communications and Navigation (SCaN) Network is being architected as an integrated set of new assets and a federation of upgraded legacy systems. The SCaN architecture for the initial missions for returning humans to the moon and beyond will include the Space Network (SN) and the Near-Earth Network (NEN). In addition to SCaN, the initial mission scenario involves a Crew Exploration Vehicle (CEV), the International Space Station (ISS) and NASA Integrated Services Network (NISN). We call the tool being developed the SCaN Network Integration and Engineering (SCaN NI&E) Simulator. The intended uses of such a simulator are: (1) to characterize performance of particular protocols and configurations in mission planning phases; (2) to optimize system configurations by testing a larger parameter space than may be feasible in either production networks or an emulated environment; (3) to test solutions in order to find issues/risks before committing more significant resources needed to produce real hardware or flight software systems. We describe two use cases of the tool: (1) standalone simulation of CEV to ISS baseline scenario to determine network performance, (2) participation in Distributed Simulation Integration Laboratory (DSIL) tests to perform function testing and verify interface and interoperability of geographically dispersed simulations/emulations.

  10. The isolation and in vitro expansion of hepatic Sca-1 progenitor cells

    SciTech Connect

    Clayton, Elizabeth

    2009-04-17

    The intra-hepatic population of liver progenitor cells expands during liver injury when hepatocyte proliferation is inhibited. These cells can be purified by density gradient centrifugation and cultured. Separated by size only this population contains small cells of hematopoietic, epithelial and endothelial lineages and is thought to contain liver stem cells. The identity of liver stem cells remains unknown although there is some evidence that tissue Sca1{sup +} CD45{sup -} cells display progenitor cell characteristics. We identified both intra-hepatic and gall bladder Sca1{sup +} cells following liver injury and expanded ex vivo Sca1 cells as part of heterogenous cell culture or as a purified population. We found significant difference between the proliferation of Sca-1 cells when plated on laminin or collagen I while proliferation of heterogenous population was not affected by the extracellular matrix indicating the necessity for culture of Sca1{sup +} cells with laminin matrix or laminin producing cells in long term liver progenitor cell cultures.

  11. SCA2 is not a major locus for ADCA type I in French families

    SciTech Connect

    Cancel, G.; Stevanin, G.; Duerr, A.; Penet, C.

    1995-10-09

    Autosomal dominant cerebellar ataxias (ADCA) of type I, a group of clinically heterogeneous neurodegenerative disorders, are known to be genetically heterogeneous since a second locus for ADCA type I (SCA2) has been identified on the long arm of chromosome 12. Linkage analysis was performed in 7 French ADCA type I families in order to estimate its frequency. We analysed 121 individuals, 39 of whom were affected. In 6 families, the SCA2 candidate interval, spanning 12.8 cM, was excluded by bi- and multipoint analysis. In one family (SAL-315), however, the maximal positive lod score reached 2.03 at the D12S79 locus. A posterior probability of 94% in favor of linkage to SCA2 was calculated by homogeneity analysis. The clinical profile of this family was similar to that of previously described SCA1 and non-SCA1 families, except that dementia was observed in 2 out of 6 patients. This may be a clinical idiosyncrasy in this family and was insufficient for a genotype-phenotype correlation. 14 refs., 1 fig., 1 tab.

  12. 41 CFR 102-36.340 - What must we do when disposing of excess aircraft?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...: Category of aircraft Description A Aircraft authorized for sale and exchange for commercial use. B Aircraft... disposing of excess aircraft? 102-36.340 Section 102-36.340 Public Contracts and Property Management Federal...-DISPOSITION OF EXCESS PERSONAL PROPERTY Personal Property Whose Disposal Requires Special Handling...

  13. 41 CFR 102-36.340 - What must we do when disposing of excess aircraft?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...: Category of aircraft Description A Aircraft authorized for sale and exchange for commercial use. B Aircraft... disposing of excess aircraft? 102-36.340 Section 102-36.340 Public Contracts and Property Management Federal...-DISPOSITION OF EXCESS PERSONAL PROPERTY Personal Property Whose Disposal Requires Special Handling...

  14. 41 CFR 102-36.340 - What must we do when disposing of excess aircraft?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...: Category of aircraft Description A Aircraft authorized for sale and exchange for commercial use. B Aircraft... disposing of excess aircraft? 102-36.340 Section 102-36.340 Public Contracts and Property Management Federal...-DISPOSITION OF EXCESS PERSONAL PROPERTY Personal Property Whose Disposal Requires Special Handling...

  15. 41 CFR 102-36.340 - What must we do when disposing of excess aircraft?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...: Category of aircraft Description A Aircraft authorized for sale and exchange for commercial use. B Aircraft... disposing of excess aircraft? 102-36.340 Section 102-36.340 Public Contracts and Property Management Federal...-DISPOSITION OF EXCESS PERSONAL PROPERTY Personal Property Whose Disposal Requires Special Handling...

  16. Aircraft recognition and pose estimation

    NASA Astrophysics Data System (ADS)

    Hmam, Hatem; Kim, Jijoong

    2000-05-01

    This work presents a geometry based vision system for aircraft recognition and pose estimation using single images. Pose estimation improves the tracking performance of guided weapons with imaging seekers, and is useful in estimating target manoeuvres and aim-point selection required in the terminal phase of missile engagements. After edge detection and straight-line extraction, a hierarchy of geometric reasoning algorithms is applied to form line clusters (or groupings) for image interpretation. Assuming a scaled orthographic projection and coplanar wings, lateral symmetry inherent in the airframe provides additional constraints to further reject spurious line clusters. Clusters that accidentally pass all previous tests are checked against the original image and are discarded. Valid line clusters are then used to deduce aircraft viewing angles. By observing that the leading edges of wings of a number of aircraft of interest are within 45 to 65 degrees from the symmetry axis, a bounded range of aircraft viewing angles can be found. This generic property offers the advantage of not requiring the storage of complete aircraft models viewed from all aspects, and can handle aircraft with flexible wings (e.g. F111). Several aircraft images associated with various spectral bands (i.e. visible and infra-red) are finally used to evaluate the system's performance.

  17. SBIR Technology Applications to Space Communications and Navigation (SCaN)

    NASA Technical Reports Server (NTRS)

    Liebrecht, Phil; Eblen, Pat; Rush, John; Tzinis, Irene

    2010-01-01

    This slide presentation reviews the mission of the Space Communications and Navigation (SCaN) Office with particular emphasis on opportunities for technology development with SBIR companies. The SCaN office manages NASA's space communications and navigation networks: the Near Earth Network (NEN), the Space Network (SN), and the Deep Space Network (DSN). The SCaN networks nodes are shown on a world wide map and the networks are described. Two types of technologies are described: Pull technology, and Push technologies. A listing of technology themes is presented, with a discussion on Software defined Radios, Optical Communications Technology, and Lunar Lasercom Space Terminal (LLST). Other technologies that are being investigated are some Game Changing Technologies (GCT) i.e., technologies that offer the potential for improving comm. or nav. performance to the point that radical new mission objectives are possible, such as Superconducting Quantum Interference Filters, Silicon Nanowire Optical Detectors, and Auto-Configuring Cognitive Communications

  18. ScaC, an Adaptor Protein Carrying a Novel Cohesin That Expands the Dockerin-Binding Repertoire of the Ruminococcus flavefaciens 17 Cellulosome

    PubMed Central

    Rincón, Marco T.; Martin, Jennifer C.; Aurilia, Vincenzo; McCrae, Sheila I.; Rucklidge, Garry J.; Reid, Martin D.; Bayer, Edward A.; Lamed, Raphael; Flint, Harry J.

    2004-01-01

    A new gene, designated scaC and encoding a protein carrying a single cohesin, was identified in the cellulolytic rumen anaerobe Ruminococcus flavefaciens 17 as part of a gene cluster that also codes for the cellulosome structural components ScaA and ScaB. Phylogenetic analysis showed that the sequence of the ScaC cohesin is distinct from the sequences of other cohesins, including the sequences of R. flavefaciens ScaA and ScaB. The scaC gene product also includes at its C terminus a dockerin module that closely resembles those found in R. flavefaciens enzymes that bind to the cohesins of the primary ScaA scaffoldin. The putative cohesin domain and the C-terminal dockerin module were cloned and overexpressed in Escherichia coli as His6-tagged products (ScaC-Coh and ScaC-Doc, respectively). Affinity probing of protein extracts of R. flavefaciens 17 separated in one-dimensional and two-dimensional gels with recombinant cohesins from ScaC and ScaA revealed that two distinct subsets of native proteins interact with ScaC-Coh and ScaA-Coh. Furthermore, ScaC-Coh failed to interact with the recombinant dockerin module from the enzyme EndB that is recognized by ScaA cohesins. On the other hand, ScaC-Doc was shown to interact specifically with the recombinant cohesin domain from ScaA, and the ScaA-Coh probe was shown to interact with a native 29-kDa protein spot identified as ScaC by matrix-assisted laser desorption ionization—time of flight mass spectrometry. These results suggest that ScaC plays the role of an adaptor scaffoldin that is bound to ScaA via the ScaC dockerin module, which, via the distinctive ScaC cohesin, expands the range of proteins that can bind to the ScaA-based enzyme complex. PMID:15090497

  19. SCaN Network Ground Station Receiver Performance for Future Service Support

    NASA Technical Reports Server (NTRS)

    Estabrook, Polly; Lee, Dennis; Cheng, Michael; Lau, Chi-Wung

    2012-01-01

    Objectives: Examine the impact of providing the newly standardized CCSDS Low Density Parity Check (LDPC) codes to the SCaN return data service on the SCaN SN and DSN ground stations receivers: SN Current Receiver: Integrated Receiver (IR). DSN Current Receiver: Downlink Telemetry and Tracking (DTT) Receiver. Early Commercial-Off-The-Shelf (COTS) prototype of the SN User Service Subsystem Component Replacement (USS CR) Narrow Band Receiver. Motivate discussion of general issues of ground station hardware design to enable simple and cheap modifications for support of future services.

  20. The effects of aircraft design on STOL ride quality

    NASA Technical Reports Server (NTRS)

    Jones, C. R.; Jacobson, I. D.

    1975-01-01

    Effects of aircraft dynamic characteristics on passenger ride quality are investigated to determine ride-quality isocontours similar to aircraft handling-qualities contours. Measurements are made on a moving-base simulator while varying the aircraft short-period and Dutch Roll frequencies and dampings. Both pilot ratings and subjective ride-quality ratings are obtained during flight. Ride and handling qualities were found to be complementary for the Dutch Roll mode, but not for the short-period mode. Regions of optimal ride and handling qualities are defined for the short-period mode, and the effects of turbulence levels studied.

  1. Characteristics of future aircraft impacting aircraft and airport compatibility

    NASA Technical Reports Server (NTRS)

    Conner, D. W.

    1982-01-01

    Results are reported of an opinion survey of selected individuals at the decision-making level within the five major manufacturers of transport aircraft in the United States and Europe. Opinions were obtained concerning both possible and probable existence of over 50 compatibility-related characteristics of transport aircraft in use in the years 1990, 2000, and 2010. The maximum size of aircraft is expected to increase, at a roughly uniform rate, to the year 2010 by 85 percent in passengers, 55 percent in airfreighter payload, and 35 percent in gross weight weight. Companion to the expected growth in payloads and gross weight was the identification of probable increases in aircraft geometrical dimensions and component capability, and use of fully double-decked passenger compartments. Wing span will increase considerably more than normally expected to provide wings of higher aspect ratio. New aircraft features coming into probable use include large turboprops, synthetic jet-A fuel, winglets, wake-vortex-reducing devices and laminar flow control. New operational concepts considered probable include steep approaches, high-speed turnoffs, and taxiway towing for the aircraft, plus passenger bypass of the terminal building, expedited handling of belly cargo and an intermodal cargo container for the payloads.

  2. Expansion of the Spinocerebellar ataxia type 10 (SCA10) repeat in a patient with Sioux Native American ancestry.

    PubMed

    Bushara, Khalaf; Bower, Matthew; Liu, Jilin; McFarland, Karen N; Landrian, Ivette; Hutter, Diane; Teive, Hélio A G; Rasmussen, Astrid; Mulligan, Connie J; Ashizawa, Tetsuo

    2013-01-01

    Spinocerebellar ataxia type 10 (SCA10), an autosomal dominant cerebellar ataxia, is caused by the expansion of the non-coding ATTCT pentanucleotide repeat in the ATAXIN 10 gene. To date, all cases of SCA10 are restricted to patients with ancestral ties to Latin American countries. Here, we report on a SCA10 patient with Sioux Native American ancestry and no reported Hispanic or Latino heritage. Neurological exam findings revealed impaired gait with mild, age-consistent cerebellar atrophy and no evidence of epileptic seizures. The age at onset for this patient, at 83 years of age, is the latest documented for SCA10 patients and is suggestive of a reduced penetrance allele in his family. Southern blot analysis showed an SCA10 expanded allele of 1400 repeats. Established SNPs surrounding the SCA10 locus showed a disease haplotype consistent with the previously described "SCA10 haplotype". This case suggests that the SCA10 expansion represents an early mutation event that possibly occurred during the initial peopling of the Americas. PMID:24278426

  3. SMRT Sequencing of Long Tandem Nucleotide Repeats in SCA10 Reveals Unique Insight of Repeat Expansion Structure

    PubMed Central

    Landrian, Ivette; Godiska, Ronald; Shanker, Savita; Yu, Fahong; Farmerie, William G.; Ashizawa, Tetsuo

    2015-01-01

    A large, non-coding ATTCT repeat expansion causes the neurodegenerative disorder, spinocerebellar ataxia type 10 (SCA10). In a subset of SCA10 patients, interruption motifs are present at the 5’ end of the expansion and strongly correlate with epileptic seizures. Thus, interruption motifs are a predictor of the epileptic phenotype and are hypothesized to act as a phenotypic modifier in SCA10. Yet, the exact internal sequence structure of SCA10 expansions remains unknown due to limitations in current technologies for sequencing across long extended tracts of tandem nucleotide repeats. We used the third generation sequencing technology, Single Molecule Real Time (SMRT) sequencing, to obtain full-length contiguous expansion sequences, ranging from 2.5 to 4.4 kb in length, from three SCA10 patients with different clinical presentations. We obtained sequence spanning the entire length of the expansion and identified the structure of known and novel interruption motifs within the SCA10 expansion. The exact interruption patterns in expanded SCA10 alleles will allow us to further investigate the potential contributions of these interrupting sequences to the pathogenic modification leading to the epilepsy phenotype in SCA10. Our results also demonstrate that SMRT sequencing is useful for deciphering long tandem repeats that pose as “gaps” in the human genome sequence. PMID:26295943

  4. Investigating B Cell Development, Natural and Primary Antibody Responses in Ly-6A/Sca-1 Deficient Mice

    PubMed Central

    Yim, Michelle; Spencer, Stacey

    2016-01-01

    Ly-6A/Stem cell antigen-1 (Ly-6A/Sca-1) is a glycosylphosphatidylinositol-anchored protein expressed on many cell types including hematopoietic stem cells (HSCs) and early lymphoid-specific progenitors. Ly-6A/Sca-1 is expressed on CD4+ T cells and plays a role in regulating cellular responses to foreign antigens. The role of Ly-6A/Sca-1 in primary antibody responses has not been defined. To investigate whether Ly-6A/Sca-1 functions in humoral immunity, we first injected Ly-6A/Sca-1-deficient and wild-type control mice with chicken ovalbumin (c-Ova) protein mixed with an adjuvant. We then assessed the ability of the mice to generate a primary antibody response against cOva. We further examined the development of B cells and circulating antibody isotypes in non-immunized Ly-6A/Sca-1deficient mice to determine if Ly6A/Sca-1 functions in development irrespective of antigen-specific immune activation. Ly-6A/Sca-1/Sca-1-deficient mice did not show any significant changes in the number of B lymphocytes in the bone marrow and peripheral lymphoid tissues. Interestingly, Ly-6A/Sca-1/Sca-1-/- mice have significantly elevated serum levels of IgA with λ light chains compared to wild type controls. B cell clusters with high reactivity to anti-IgA λ monoclonal antibody were detected in the lamina propria of the gut, though this was not observed in the bone marrow and peripheral lymphoid tissues. Despite these differences, the Ly-6A/Sca-1deficient mice generated a similar primary antibody response when compared to the wild-type mice. In summary, we conclude that the primary antibody response to cOva antigen is similar in Ly-6A/Sca-1deficient and sufficient mice. In addition, we report significantly higher expression of the immunoglobulin λ light chain by B cells in lamina propria of Ly-6A/Sca-1deficient mice when compared to the wild-type control. PMID:27322740

  5. Tissue transglutaminase crosslinks ataxin-1: Possible role in SCA1 pathogenesis

    PubMed Central

    D’Souza, D.R.; Wei, J.; Shao, Q.; Hebert, M.D.; Subramony, S.H.; Vig, P.J.S.

    2007-01-01

    Transglutaminase type 2 (TG2) has recently been implicated in crosslinking of mutant huntingtin protein into aggregates. Here we show that TG2 also crosslinks spinocerebellar ataxia-1 (SCA1) gene product ataxin-1. HeLa cell lysates expressing GFP tagged ataxin-1 with 2, 30 or 82 glutamines showed covalent crosslinking of ataxin-1 when incubated with exogenously added TG2. This crosslinking was inhibited by TG2 inhibitor cystamine. SCA1 transgenic mice which overexpress the mutant ataxin-1 in cerebellar Purkinje cells showed elevated nuclear TG2 in the absence of ataxin-1 nuclear aggregates. The addition of purified TG2 to the nuclear extracts or addition of SCA1 nuclear TG2 to GFP-Q82 HeLa cell lysates resulted in the formation of insoluble aggregates. These data indicate that ataxin-1 is a substrate of TG2. Further, in SCA1 TG2 may translocate to the nucleus in response to nuclear accumulation of mutant ataxin-1 at early stages of the disease. PMID:17045396

  6. Crosstalking noncoding RNAs contribute to cell-specific neurodegeneration in SCA7

    PubMed Central

    Tan, Jennifer Y.; Sirey, Tamara; Watson, Lauren M.; Curtis, Helen J.; Marinello, Martina; Alves, Sandro; Steinkraus, Bruno; Cooper, Sarah; Nesterova, Tatyana; Brockdorff, Neil; Fulga, Tudor; Brice, Alexis; Sittler, Annie; Oliver, Peter L.; Wood, Matthew J.; Ponting, Chris P.; Marques, Ana C.

    2014-01-01

    What causes the tissue-specific pathology of diseases resulting from mutations in housekeeping genes? Specifically, in Spinocerebellar ataxia type 7 (SCA7), a neurodegenerative disorder caused by a CAG repeat expansion in ATXN7- an essential component of the mammalian transcription co-activation complex, STAGA- the factors underlying the characteristic progressive cerebellar and retinal degeneration observed in patients were unknown. We found that STAGA is required for the transcription initiation of miR-124, which in turn mediates the post-transcriptional crosstalk between lnc-SCA7, a conserved long noncoding RNA, and ATXN7. In SCA7, mutations in ATXN7 disrupt these regulatory interactions and result in a neuron-specific increase in ATXN7 abundance. Strikingly in mouse, this increase is most prominent in the SCA7 disease-relevant tissues, namely the retina and cerebellum. Our results illustrate how noncoding RNA-mediated feedback regulation of a ubiquitously expressed housekeeping gene may contribute to specific neurodegeneration. PMID:25306109

  7. Fusiform superior cerebellar artery aneurysm treated with STA-SCA bypass and trapping

    PubMed Central

    Lamis, Fabricio C.; De Paiva Neto, Manoel A.; Cavalheiro, Sergio

    2014-01-01

    Background: Fusiform aneurysms of cerebellar arteries are rare. Different surgical techniques to address these challenging lesions have been described, and their application depends on whether the goal is to maintain the flow in the parent vessel or to occlude it. Case Description: The authors reported a case of a fusiform aneurysm located in the lateral pontomesencephalic segment of the superior cerebellar artery (SCA) in a 32-year-old man who presented with subarachnoid hemorrhage. The patient was subjected to aneurysm trapping followed by a bypass between the superficial temporal artery (STA) and SCA and had an uneventful recovery. Conclusions: Although only a few cases of fusiform aneurysms in the supracerebellar artery have been reported in the literature, the treatment strategies adopted were diverse. In selected cases of patients in good neurological condition with ruptured fusiform aneurysms at the proximal segments of SCA and who have poor evidence of collateral supply, the possibility of a STA-SCA bypass with aneurysm trapping must be considered. A review of the current treatment modalities of this pathology is also presented. PMID:25071936

  8. Subsidiary Communications Authorization (SCA) Newsletter, Volume 4, Numbers 1-4.

    ERIC Educational Resources Information Center

    SCAlogram, 1976

    1976-01-01

    This edition includes the February, May, June, and July 1976 issues of the Subsidiary Communications Authorization (SCA) newsletter. The February issue discusses the following news items: (1) Corporation for Public Broadcasting endorsement of print handicapped pilot concept; (2) second radio reading service conference to be held in Minneapolis;…

  9. Pathological repeat variation at the SCA17/TBP gene in south Indian patients.

    PubMed

    Lone, Waseem Gul; Khan, Imran Ali; Shaik, Noor Ahmad; Meena, Angmuthu Kanikannan; Rao, Kaipa Prabhakar; Hasan, Qurratulain

    2015-12-15

    Despite the intense debate around the repeat instability reported on the large group of neurological disorders caused by trinucleotide repeat expansions, little is known about the mutation process underlying alleles in the normal range, diseases range, large normal alleles (LNAs). In this study, we assessed the CAG repeats at SCA17 in 188 clinical SCA patients and 100 individuals without any neurological signs. This highly polymorphic population displayed high variability in the CAG repeats and ranged from 19-38 CAG repeats in patients with mode of 20 and 19-32 CAG repeats in controls with mode of 24. The triplet repeat expansion was not detected in any of the 188 patients, as per the reference pathogenic range (>43 repeats); however, 2.7% of the patients had >33 CAG repeats with a clinical phenotype close to what is expected of SCA 17 patients. The findings of this study implicate a more sophisticated interpretation of SCA17 gene and raise the question about the diagnostic thresh hold between normal and expanded repeats in our population. PMID:26476771

  10. Principal Component Analysis of Cerebellar Shape on MRI Separates SCA Types 2 and 6 into Two Archetypal Modes of Degeneration

    PubMed Central

    Jung, Brian C.; Choi, Soo I.; Du, Annie X.; Cuzzocreo, Jennifer L.; Geng, Zhuo Z.; Ying, Howard S.; Perlman, Susan L.; Toga, Arthur W.; Prince, Jerry L.

    2014-01-01

    Although “cerebellar ataxia” is often used in reference to a disease process, presumably there are different underlying pathogenetic mechanisms for different subtypes. Indeed, spinocerebellar ataxia (SCA) types 2 and 6 demonstrate complementary phenotypes, thus predicting a different anatomic pattern of degeneration. Here, we show that an unsupervised classification method, based on principal component analysis (PCA) of cerebellar shape characteristics, can be used to separate SCA2 and SCA6 into two classes, which may represent disease-specific archetypes. Patients with SCA2 (n=11) and SCA6 (n=7) were compared against controls (n=15) using PCA to classify cerebellar anatomic shape characteristics. Within the first three principal components, SCA2 and SCA6 differed from controls and from each other. In a secondary analysis, we studied five additional subjects and found that these patients were consistent with the previously defined archetypal clusters of clinical and anatomical characteristics. Secondary analysis of five subjects with related diagnoses showed that disease groups that were clinically and pathophysiologically similar also shared similar anatomic characteristics. Specifically, Archetype #1 consisted of SCA3 (n=1) and SCA2, suggesting that cerebellar syndromes accompanied by atrophy of the pons may be associated with a characteristic pattern of cerebellar neurodegeneration. In comparison, Archetype #2 was comprised of disease groups with pure cerebellar atrophy (episodic ataxia type 2 (n=1), idiopathic late-onset cerebellar ataxias (n=3), and SCA6). This suggests that cerebellar shape analysis could aid in discriminating between different pathologies. Our findings further suggest that magnetic resonance imaging is a promising imaging biomarker that could aid in the diagnosis and therapeutic management in patients with cerebellar syndromes. PMID:22258915

  11. Principal component analysis of cerebellar shape on MRI separates SCA types 2 and 6 into two archetypal modes of degeneration.

    PubMed

    Jung, Brian C; Choi, Soo I; Du, Annie X; Cuzzocreo, Jennifer L; Geng, Zhuo Z; Ying, Howard S; Perlman, Susan L; Toga, Arthur W; Prince, Jerry L; Ying, Sarah H

    2012-12-01

    Although "cerebellar ataxia" is often used in reference to a disease process, presumably there are different underlying pathogenetic mechanisms for different subtypes. Indeed, spinocerebellar ataxia (SCA) types 2 and 6 demonstrate complementary phenotypes, thus predicting a different anatomic pattern of degeneration. Here, we show that an unsupervised classification method, based on principal component analysis (PCA) of cerebellar shape characteristics, can be used to separate SCA2 and SCA6 into two classes, which may represent disease-specific archetypes. Patients with SCA2 (n=11) and SCA6 (n=7) were compared against controls (n=15) using PCA to classify cerebellar anatomic shape characteristics. Within the first three principal components, SCA2 and SCA6 differed from controls and from each other. In a secondary analysis, we studied five additional subjects and found that these patients were consistent with the previously defined archetypal clusters of clinical and anatomical characteristics. Secondary analysis of five subjects with related diagnoses showed that disease groups that were clinically and pathophysiologically similar also shared similar anatomic characteristics. Specifically, Archetype #1 consisted of SCA3 (n=1) and SCA2, suggesting that cerebellar syndromes accompanied by atrophy of the pons may be associated with a characteristic pattern of cerebellar neurodegeneration. In comparison, Archetype #2 was comprised of disease groups with pure cerebellar atrophy (episodic ataxia type 2 (n=1), idiopathic late-onset cerebellar ataxias (n=3), and SCA6). This suggests that cerebellar shape analysis could aid in discriminating between different pathologies. Our findings further suggest that magnetic resonance imaging is a promising imaging biomarker that could aid in the diagnosis and therapeutic management in patients with cerebellar syndromes. PMID:22258915

  12. The Sca2 Autotransporter Protein from Rickettsia conorii Is Sufficient To Mediate Adherence to and Invasion of Cultured Mammalian Cells▿

    PubMed Central

    Cardwell, Marissa M.; Martinez, Juan J.

    2009-01-01

    Obligate intracellular bacteria of the genus Rickettsia must adhere to and invade the host endothelium in order to establish an infection. These processes require the interaction of rickettsial surface proteins with mammalian host cell receptors. A previous bioinformatic analysis of sequenced rickettsial species identified a family of at least 17 predicted “surface cell antigen” (sca) genes whose products resemble autotransporter proteins. Two members of this family, rOmpA and rOmpB of spotted fever group (SFG) rickettsiae have been identified as adhesion and invasion factors, respectively; however, little is known about the putative functions of the other sca gene products. An intact sca2 gene is found in the majority of pathogenic SFG rickettsiae and, due to its sequence conservation among these species, we predict that Sca2 may play an important function at the rickettsial surface. Here we have shown that sca2 is transcribed and expressed in Rickettsia conorii and have used a heterologous gain-of-function assay in E. coli to determine the putative role of Sca2. Using this system, we have demonstrated that expression of Sca2 at the outer membrane of nonadherent, noninvasive E. coli is sufficient to mediate adherence to and invasion of a panel of mammalian cells, including endothelial cells. Furthermore, soluble Sca2 protein is capable of diminishing R. conorii invasion of cultured mammalian cells. This is the first evidence that Sca2 participates in the interaction between SFG rickettsiae and host cells and suggests that in addition to other surface proteins, Sca2 may play a critical role in rickettsial pathogenesis. PMID:19805531

  13. Demonstration by heterologous expression that the Leishmania SCA1 gene encodes an arabinopyranosyltransferase.

    PubMed

    Goswami, Mamta; Dobson, Deborah E; Beverley, Stephen M; Turco, Salvatore J

    2006-03-01

    In part of the life cycle within their sand fly vector, Leishmania major parasites first attach to the fly's midgut through their main surface adhesin lipophosphoglycan (LPG) and later resynthesize a structurally distinct LPG that results in detachment and eventual transmission. One of these structural modifications requires the addition of alpha1,2-D-arabinopyranose caps to beta1,3-galactose side chains in the phosphoglycan repeat unit domain of LPG. We had previously identified two side chain arabinose genes (SCA1/2) that were involved in the alpha1,2-D-Arap capping. SCA1/2 exhibit canonical glycosyltransferase motifs, and overexpression of either gene leads to elevated microsomal alpha1,2-D-ArapT activity, resulting in arabinopyranosylation of beta1,3-Gal side chains in LPG (hereafter called side chain D-arabinopyranosyltransferase [sc-D-ArapT]). Heterologous expression in a null arabinose background was used to determine whether the SCA1 gene encodes the actual sc-D-ArapT. SCA1 expression constructs introduced into both mammalian COS-7 cells and the baculovirus-sf9 cell system exhibited considerable expression of the protein. However, functional sc-D-ArapT activity was observed only in the latter. In in vitro assays incubated with guanidine 59-diphosphate (GDP)-D-[3H]Arap as the sugar donor and utilizing exogenous LPG as an acceptor, significant sc-D-ArapT activity was observed when microsomes from the baculovirus-sf9 cells were incubated in presence of the LPG acceptor. No activity was observed in the absence of LPG. These results demonstrate that SCA1 encodes a sc-D-ArapT and provide the first example of heterologous expression of a D-ArapT gene. PMID:16272216

  14. STS-68 on Runway with 747 SCA - Columbia Ferry Flyby

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The space shuttle Endeavour receives a high-flying salute from its sister shuttle, Columbia, atop NASA's Shuttle Carrier Aircraft, shortly after Endeavor's landing 12 October 1994, at Edwards, California, to complete mission STS-68. Columbia was being ferried from the Kennedy Space Center, Florida, to Air Force Plant 42, Palmdale, California, where it will undergo six months of inspections, modifications, and systems upgrades. The STS-68 11-day mission was devoted to radar imaging of Earth's geological features with the Space Radar Laboratory. The orbiter is surrounded by equipment and personnel that make up the ground support convoy that services the space vehicles as soon as they land. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the

  15. Shuttle Enterprise Mated to 747 SCA for Delivery to Smithsonian

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The Space Shuttle Enterprise atop the NASA 747 Shuttle Carrier Aircraft as it leaves NASA's Dryden Flight Research Center, Edwards, California. The Enterprise, first orbiter built, was not spaceflight rated and was used in 1977 to verify the landing, approach, and glide characteristics of the orbiters. It was also used for engineering fit-checks at the shuttle launch facilities. Following approach and landing tests in 1977 and its use as an engineering vehicle, Enterprise was donated to the National Air and Space Museum in Washington, D.C. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and can be reused on future flights. Some of these orbital laboratories, like the

  16. STOL Aircraft

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Michael E. Fisher, President of AeroVisions International, has introduced the Culex light twin engine aircraft which offers economy of operation of a single engine plane, the ability to fly well on one engine, plus the capability of flying from short, unimproved fields of takeoff and landing distances less than 35 feet. Key element of design is an airfoil developed by Langley. Culex was originally intended to be factory built aircraft for special utility markets. However, it is now offered as a build-it-yourself kit plane.

  17. Vertical flight path steering system for aircraft

    NASA Technical Reports Server (NTRS)

    Lambregts, Antonius A. (Inventor)

    1983-01-01

    Disclosed is a vertical flight path angle steering system for aircraft, utilizing a digital flight control computer which processes pilot control inputs and aircraft response parameters into suitable elevator commands and control information for display to the pilot on a cathode ray tube. The system yields desirable airplane control handling qualities and responses as well as improvements in pilot workload and safety during airplane operation in the terminal area and under windshear conditions.

  18. Cooper-Harper Experience Report for Spacecraft Handling Qualities Applications

    NASA Technical Reports Server (NTRS)

    Bailey, Randall E.; Jackson, E. Bruce; Bilimoria, Karl D.; Mueller, Eric R.; Frost, Chad R.; Alderete, Thomas S.

    2009-01-01

    A synopsis of experience from the fixed-wing and rotary-wing aircraft communities in handling qualities development and the use of the Cooper-Harper pilot rating scale is presented as background for spacecraft handling qualities research, development, test, and evaluation (RDT&E). In addition, handling qualities experiences and lessons-learned from previous United States (US) spacecraft developments are reviewed. This report is intended to provide a central location for references, best practices, and lessons-learned to guide current and future spacecraft handling qualities RDT&E.

  19. STS Challenger Mated to 747 SCA for Initial Delivery to Florida

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The Space Shuttle orbiter Challenger atop NASA's Boeing 747 Shuttle Carrier Aircraft (SCA), NASA 905, after leaving the Dryden Flight Research Center, Edwards, California, for the ferry flight that took the orbiter to the Kennedy Space Center in Florida for its first launch. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and can be reused on future flights. Some of these orbital laboratories, like the Spacelab, provide facilities for several specialists to conduct experiments in such fields as medicine, astronomy, and materials manufacturing. Some types of satellites deployed by Space Shuttles include those involved in environmental and resources protection, astronomy

  20. Shuttle Discovery Being Unloaded from SCA-747 at Palmdale, California, Maintenance Facility

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Space Shuttle Discovery being unloaded from NASA's Boeing 747 Shuttle Carrier Aircraft (SCA) at Rockwell Aerospace's Palmdale facility for nine months of scheduled maintenance. Discovery and the 747 were completing a two-day flight from Kennedy Space Center, Florida, that began at 7:04 a.m. Eastern Standard Time on 27 September and included an overnight stop at Salt Lake City International Airport, Utah. At the conclusion of this mission, Discovery had flown 21 shuttle missions, totaling more than 142 days in orbit. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and can be reused on future flights. Some of these orbital laboratories, like the Spacelab, provide

  1. STS-68 747 SCA Ferry Flight Takeoff for Delivery to Kennedy Space Center, Florida

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Space Shuttle Columbia, atop NASA's 747 Shuttle Carrier Aircraft (SCA), taking off for the Kennedy Space Center shortly after its landing on 12 October 1994, at Edwards, California, to complete mission STS-68. Columbia was being ferried from the Kennedy Space Center, Florida, to Air Force Plant 42, Palmdale, California, where it will undergo six months of inspections, modifications, and systems upgrades. The STS-68 11-day mission was devoted to radar imaging of Earth's geological features with the Space Radar Laboratory. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and can be reused on future flights. Some of these orbital laboratories, like the Spacelab

  2. STS-66 Atlantis 747 SCA Ferry Flight Morning Takeoff for Delivery to Kennedy Space Center, Florida

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The space shuttle Atlantis atop NASA's 747 Shuttle Carrier Aircraft (SCA) during takeoff for a return ferry flight to the Kennedy Space Center from Edwards, California. The STS-66 mission was dedicated to the third flight of the Atmospheric Laboratory for Applications and Science-3 (ATLAS-3), part of NASA's Mission to Planet Earth program. The astronauts also deployed and retrieved a free-flying satellite designed to study the middle and lower thermospheres and perform a series of experiments covering life sciences research and microgravity processing. The landing was at 7:34 a.m. (PST) 14 November 1994, after being waved off from the Kennedy Space Center, Florida, due to adverse weather. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the

  3. STS-68 on Runway with 747 SCA - Columbia Ferry Flyby

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The space shuttle Endeavour receives a high-flying salute from its sister shuttle, Columbia, atop NASA's Shuttle Carrier Aircraft, shortly after Endeavor's landing 12 October 1994, at Edwards, California, to complete mission STS-68. Columbia was being ferried from the Kennedy Space Center, Florida, to Air Force Plant 42, Palmdale, California, where it will undergo six months of inspections, modifications, and systems upgrades. The STS-68 11-day mission was devoted to radar imaging of Earth's geological features with the Space Radar Laboratory. The orbiter is surrounded by equipment and personnel that make up the ground support convoy that services the space vehicles as soon as they land. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the

  4. Aircraft cybernetics

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The use of computers for aircraft control, flight simulation, and inertial navigation is explored. The man-machine relation problem in aviation is addressed. Simple and self-adapting autopilots are described and the assets and liabilities of digital navigation techniques are assessed.

  5. ScaRaB: first results of absolute and cross calibration

    NASA Astrophysics Data System (ADS)

    Trémas, Thierry L.; Aznay, Ouahid; Chomette, Olivier

    2015-10-01

    ScaRaB (SCAnner for RAdiation Budget) is the name of three radiometers whose two first flight models have been launched in 1994 and 1997. The instruments were mounted on-board Russian satellites, METEOR and RESURS. On October 12th 2011, a last model has been launched from the Indian site of Sriharikota. ScaRaB is a passenger of MEGHA-TROPIQUES, an Indo-French joint Satellite Mission for studying the water cycle and energy exchanges in the tropics. ScaRaB is composed of four parallel and independent channels. Channel-2 and channel-3 are considered as the main ones. Channel-1 is dedicated to measure solar radiance (0.5 to 0.7 μm) while channel-4 (10 to 13 μm) is an infrared window. The absolute calibration of ScaRab is assured by internal calibration sources (black bodies and a lamp for channel-1). However, during the commissioning phase, the lamp used for the absolute calibration of channel-1 revealed to be inaccurate. We propose here an alternative calibration method based on terrestrial targets. Due to the spectral range of channel-1, only calibration over desert sites (temporal monitoring) and clouds (cross band) is suitable. Desert sites have been widely used for sensor calibration since they have a stable spectral response over time. Because of their high reflectances, the atmospheric effect on the upward radiance is relatively minimal. In addition, they are spatially uniform. Their temporal instability without atmospheric correction has been determined to be less than 1-2% over a year. Very-high-altitude (10 km) bright clouds are good validation targets in the visible and near-infrared spectra because of their high spectrally consistent reflectance. If the clouds are very high, there is no need to correct aerosol scattering and water vapor absorption as both aerosol and water vapor are distributed near the surface. Only Rayleigh scattering and ozone absorption need to be considered. This method has been found to give a 4% uncertainty. Radiometric cross

  6. Application of active controls to civil transport aircraft

    NASA Technical Reports Server (NTRS)

    Taylor, L. W., Jr.

    1975-01-01

    The impact of active controls on civil transport aircraft and some of the complex problems involved are described. The approach taken by NASA as part of the Active Control Technology Program is discussed to integrate active controls in the conceptual design phase. It is shown that when handled correctly, active controls improve aircraft performance.

  7. The Murine Bladder Supports a Population of Stromal Sca-1+/CD34+/lin- Mesenchymal Stem Cells.

    PubMed

    Lilly, Meredith A; Kulkulka, Natalie A; Firmiss, Paula R; Ross, Michael J; Flum, Andrew S; Santos, Grace B Delos; Bowen, Diana K; Dettman, Robert W; Gong, Edward M

    2015-01-01

    Bladder fibrosis is an undesired end point of injury of obstruction and often renders the smooth muscle layer noncompliant. In many cases, the long-term effect of bladder fibrosis is renal failure. Despite our understanding of the progression of this disease, little is known about the cellular mechanisms that lead to a remodeled bladder wall. Resident stem (progenitor) cells have been identified in various organs such as the brain, heart and lung. These cells function normally during organ homeostasis, but become dysregulated after organ injury. Here, we aimed to characterize a mesenchymal progenitor cell population as a first step in understanding its role in bladder fibrosis. Using fluorescence activated cell sorting (FACS), we identified a Sca-1+/ CD34+/ lin- (PECAM-: CD45-: Ter119-) population in the adult murine bladder. These cells were localized to the stromal layer of the adult bladder and appeared by postnatal day 1. Cultured Sca-1+/ CD34+/ lin- bladder cells self-renewed, formed colonies and spontaneously differentiated into cells expressing smooth muscle genes. These cells differentiated into other mesenchymal lineages (chondrocytes, adipocytes and osteocytes) upon culture in induction medium. Both acute and partial obstruction of the bladder reduced expression of CD34 and changed localization of Sca-1 to the urothelium. Partial obstruction resulted in upregulation of fibrosis genes within the Sca-1+/CD34+/lin- population. Our data indicate a resident, mesenchymal stem cell population in the bladder that is altered by bladder obstruction. These findings provide new information about the cellular changes in the bladder that may be associated with bladder fibrosis. PMID:26540309

  8. Extensive White Matter Alterations and Its Correlations with Ataxia Severity in SCA 2 Patients

    PubMed Central

    Hernandez-Castillo, Carlos R.; Galvez, Victor; Mercadillo, Roberto; Diaz, Rosalinda; Campos-Romo, Aurelio; Fernandez-Ruiz, Juan

    2015-01-01

    Background Previous studies of SCA2 have revealed significant degeneration of white matter tracts in cerebellar and cerebral regions. The motor deficit in these patients may be attributable to the degradation of projection fibers associated with the underlying neurodegenerative process. However, this relationship remains unclear. Statistical analysis of diffusion tensor imaging enables an unbiased whole-brain quantitative comparison of the diffusion proprieties of white matter tracts in vivo. Methods Fourteen genetically confirmed SCA2 patients and aged-matched healthy controls participated in the study. Tract-based spatial statistics were performed to analyze structural white matter damage using two different measurements: fractional anisotropy (FA) and mean diffusivity (MD). Significant diffusion differences were correlated with the patient's ataxia impairment. Results Our analysis revealed decreased FA mainly in the inferior/middle/superior cerebellar peduncles, the bilateral posterior limb of the internal capsule and the bilateral superior corona radiata. Increases in MD were found mainly in cerebellar white matter, medial lemniscus, and middle cerebellar peduncle, among other regions. Clinical impairment measured with the SARA score correlated with FA in superior parietal white matter and bilateral anterior corona radiata. Correlations with MD were found in cerebellar white matter and the middle cerebellar peduncle. Conclusion Our findings show significant correlations between diffusion measurements in key areas affected in SCA2 and measures of motor impairment, suggesting a disruption of information flow between motor and sensory-integration areas. These findings result in a more comprehensive view of the clinical impact of the white matter degeneration in SCA2. PMID:26263162

  9. Case studies on the development of ScaLAPACK and the NAG numerical PVM library

    SciTech Connect

    Dongarra, J.J.; Hammarling, S.; Petitet, A.

    1996-12-31

    In this paper we look at the development of ScaLAPACK, a software library for dense and banded numerical linear algebra, and the NAG Numerical PVM Library, which includes software for dense and sparse linear algebra, quadrature, optimization and random number generation. Both libraries are aimed at distributed memory machines, including networks of workstations. The paper concentrates on the underlying design and the testing of the libraries.

  10. The Murine Bladder Supports a Population of Stromal Sca-1+/CD34+/lin- Mesenchymal Stem Cells

    PubMed Central

    Lilly, Meredith A.; Kulkulka, Natalie A.; Firmiss, Paula R.; Ross, Michael J.; Flum, Andrew S.; Santos, Grace B. Delos; Bowen, Diana K.; Dettman, Robert W.; Gong, Edward M.

    2015-01-01

    Bladder fibrosis is an undesired end point of injury of obstruction and often renders the smooth muscle layer noncompliant. In many cases, the long-term effect of bladder fibrosis is renal failure. Despite our understanding of the progression of this disease, little is known about the cellular mechanisms that lead to a remodeled bladder wall. Resident stem (progenitor) cells have been identified in various organs such as the brain, heart and lung. These cells function normally during organ homeostasis, but become dysregulated after organ injury. Here, we aimed to characterize a mesenchymal progenitor cell population as a first step in understanding its role in bladder fibrosis. Using fluorescence activated cell sorting (FACS), we identified a Sca-1+/ CD34+/ lin- (PECAM-: CD45-: Ter119-) population in the adult murine bladder. These cells were localized to the stromal layer of the adult bladder and appeared by postnatal day 1. Cultured Sca-1+/ CD34+/ lin- bladder cells self-renewed, formed colonies and spontaneously differentiated into cells expressing smooth muscle genes. These cells differentiated into other mesenchymal lineages (chondrocytes, adipocytes and osteocytes) upon culture in induction medium. Both acute and partial obstruction of the bladder reduced expression of CD34 and changed localization of Sca-1 to the urothelium. Partial obstruction resulted in upregulation of fibrosis genes within the Sca-1+/CD34+/lin- population. Our data indicate a resident, mesenchymal stem cell population in the bladder that is altered by bladder obstruction. These findings provide new information about the cellular changes in the bladder that may be associated with bladder fibrosis. PMID:26540309

  11. SCaLeM: A Framework for Characterizing and Analyzing Execution Models

    SciTech Connect

    Chavarría-Miranda, Daniel; Manzano Franco, Joseph B.; Krishnamoorthy, Sriram; Vishnu, Abhinav; Barker, Kevin J.; Hoisie, Adolfy

    2014-10-13

    As scalable parallel systems evolve towards more complex nodes with many-core architectures and larger trans-petascale & upcoming exascale deployments, there is a need to understand, characterize and quantify the underlying execution models being used on such systems. Execution models are a conceptual layer between applications & algorithms and the underlying parallel hardware and systems software on which those applications run. This paper presents the SCaLeM (Synchronization, Concurrency, Locality, Memory) framework for characterizing and execution models. SCaLeM consists of three basic elements: attributes, compositions and mapping of these compositions to abstract parallel systems. The fundamental Synchronization, Concurrency, Locality and Memory attributes are used to characterize each execution model, while the combinations of those attributes in the form of compositions are used to describe the primitive operations of the execution model. The mapping of the execution model’s primitive operations described by compositions, to an underlying abstract parallel system can be evaluated quantitatively to determine its effectiveness. Finally, SCaLeM also enables the representation and analysis of applications in terms of execution models, for the purpose of evaluating the effectiveness of such mapping.

  12. PDGFRα demarcates the cardiogenic clonogenic Sca1+ stem/progenitor cell in adult murine myocardium

    PubMed Central

    Noseda, Michela; Harada, Mutsuo; McSweeney, Sara; Leja, Thomas; Belian, Elisa; Stuckey, Daniel J.; Abreu Paiva, Marta S.; Habib, Josef; Macaulay, Iain; de Smith, Adam J.; al-Beidh, Farah; Sampson, Robert; Lumbers, R. Thomas; Rao, Pulivarthi; Harding, Sian E.; Blakemore, Alexandra I. F.; Eirik Jacobsen, Sten; Barahona, Mauricio; Schneider, Michael D.

    2015-01-01

    Cardiac progenitor/stem cells in adult hearts represent an attractive therapeutic target for heart regeneration, though (inter)-relationships among reported cells remain obscure. Using single-cell qRT–PCR and clonal analyses, here we define four subpopulations of cardiac progenitor/stem cells in adult mouse myocardium all sharing stem cell antigen-1 (Sca1), based on side population (SP) phenotype, PECAM-1 (CD31) and platelet-derived growth factor receptor-α (PDGFRα) expression. SP status predicts clonogenicity and cardiogenic gene expression (Gata4/6, Hand2 and Tbx5/20), properties segregating more specifically to PDGFRα+ cells. Clonal progeny of single Sca1+ SP cells show cardiomyocyte, endothelial and smooth muscle lineage potential after cardiac grafting, augmenting cardiac function although durable engraftment is rare. PDGFRα− cells are characterized by Kdr/Flk1, Cdh5, CD31 and lack of clonogenicity. PDGFRα+/CD31− cells derive from cells formerly expressing Mesp1, Nkx2-5, Isl1, Gata5 and Wt1, distinct from PDGFRα−/CD31+ cells (Gata5 low; Flk1 and Tie2 high). Thus, PDGFRα demarcates the clonogenic cardiogenic Sca1+ stem/progenitor cell. PMID:25980517

  13. PDGFRα demarcates the cardiogenic clonogenic Sca1+ stem/progenitor cell in adult murine myocardium.

    PubMed

    Noseda, Michela; Harada, Mutsuo; McSweeney, Sara; Leja, Thomas; Belian, Elisa; Stuckey, Daniel J; Abreu Paiva, Marta S; Habib, Josef; Macaulay, Iain; de Smith, Adam J; al-Beidh, Farah; Sampson, Robert; Lumbers, R Thomas; Rao, Pulivarthi; Harding, Sian E; Blakemore, Alexandra I F; Jacobsen, Sten Eirik; Barahona, Mauricio; Schneider, Michael D

    2015-01-01

    Cardiac progenitor/stem cells in adult hearts represent an attractive therapeutic target for heart regeneration, though (inter)-relationships among reported cells remain obscure. Using single-cell qRT-PCR and clonal analyses, here we define four subpopulations of cardiac progenitor/stem cells in adult mouse myocardium all sharing stem cell antigen-1 (Sca1), based on side population (SP) phenotype, PECAM-1 (CD31) and platelet-derived growth factor receptor-α (PDGFRα) expression. SP status predicts clonogenicity and cardiogenic gene expression (Gata4/6, Hand2 and Tbx5/20), properties segregating more specifically to PDGFRα(+) cells. Clonal progeny of single Sca1(+) SP cells show cardiomyocyte, endothelial and smooth muscle lineage potential after cardiac grafting, augmenting cardiac function although durable engraftment is rare. PDGFRα(-) cells are characterized by Kdr/Flk1, Cdh5, CD31 and lack of clonogenicity. PDGFRα(+)/CD31(-) cells derive from cells formerly expressing Mesp1, Nkx2-5, Isl1, Gata5 and Wt1, distinct from PDGFRα(-)/CD31(+) cells (Gata5 low; Flk1 and Tie2 high). Thus, PDGFRα demarcates the clonogenic cardiogenic Sca1(+) stem/progenitor cell. PMID:25980517

  14. Control of Next Generation Aircraft and Wind Turbines

    NASA Technical Reports Server (NTRS)

    Frost, Susan

    2010-01-01

    The first part of this talk will describe some of the exciting new next generation aircraft that NASA is proposing for the future. These aircraft are being designed to reduce aircraft fuel consumption and environmental impact. Reducing the aircraft weight is one approach that will be used to achieve these goals. A new control framework will be presented that enables lighter, more flexible aircraft to maintain aircraft handling qualities, while preventing the aircraft from exceeding structural load limits. The second part of the talk will give an overview of utility-scale wind turbines and their control. Results of collaboration with Dr. Balas will be presented, including new theory to adaptively control the turbine in the presence of structural modes, with the focus on the application of this theory to a high-fidelity simulation of a wind turbine.

  15. Grain Handling and Storage.

    ERIC Educational Resources Information Center

    Harris, Troy G.; Minor, John

    This text for a secondary- or postecondary-level course in grain handling and storage contains ten chapters. Chapter titles are (1) Introduction to Grain Handling and Storage, (2) Elevator Safety, (3) Grain Grading and Seed Identification, (4) Moisture Control, (5) Insect and Rodent Control, (6) Grain Inventory Control, (7) Elevator Maintenance,…

  16. Educating with Aircraft Models

    ERIC Educational Resources Information Center

    Steele, Hobie

    1976-01-01

    Described is utilization of aircraft models, model aircraft clubs, and model aircraft magazines to promote student interest in aerospace education. The addresses for clubs and magazines are included. (SL)

  17. Flight simulator for hypersonic vehicle and a study of NASP handling qualities

    NASA Technical Reports Server (NTRS)

    Ntuen, Celestine A.; Park, Eui H.; Deeb, Joseph M.; Kim, Jung H.

    1992-01-01

    The research goal of the Human-Machine Systems Engineering Group was to study the existing handling quality studies in aircraft with sonic to supersonic speeds and power in order to understand information requirements needed for a hypersonic vehicle flight simulator. This goal falls within the NASA task statements: (1) develop flight simulator for hypersonic vehicle; (2) study NASP handling qualities; and (3) study effects of flexibility on handling qualities and on control system performance. Following the above statement of work, the group has developed three research strategies. These are: (1) to study existing handling quality studies and the associated aircraft and develop flight simulation data characterization; (2) to develop a profile for flight simulation data acquisition based on objective statement no. 1 above; and (3) to develop a simulator and an embedded expert system platform which can be used in handling quality experiments for hypersonic aircraft/flight simulation training.

  18. A design procedure and handling quality criteria for lateral directional flight control systems

    NASA Technical Reports Server (NTRS)

    Stein, G.; Henke, A. H.

    1972-01-01

    A practical design procedure for aircraft augmentation systems is described based on quadratic optimal control technology and handling-quality-oriented cost functionals. The procedure is applied to the design of a lateral-directional control system for the F4C aircraft. The design criteria, design procedure, and final control system are validated with a program of formal pilot evaluation experiments.

  19. Allele-specific silencing of mutant Ataxin-7 in SCA7 patient-derived fibroblasts.

    PubMed

    Scholefield, Janine; Watson, Lauren; Smith, Danielle; Greenberg, Jacquie; Wood, Matthew J A

    2014-12-01

    Polyglutamine (polyQ) disorders are inherited neurodegenerative conditions defined by a common pathogenic CAG repeat expansion leading to a toxic gain-of-function of the mutant protein. Consequences of this toxicity include activation of heat-shock proteins (HSPs), impairment of the ubiquitin-proteasome pathway and transcriptional dysregulation. Several studies in animal models have shown that reducing levels of toxic protein using small RNAs would be an ideal therapeutic approach for such disorders, including spinocerebellar ataxia-7 (SCA7). However, testing such RNA interference (RNAi) effectors in genetically appropriate patient cell lines with a disease-relevant phenotype has yet to be explored. Here, we have used primary adult dermal fibroblasts from SCA7 patients and controls to assess the endogenous allele-specific silencing of ataxin-7 by two distinct siRNAs. We further identified altered expression of two disease-relevant transcripts in SCA7 patient cells: a twofold increase in levels of the HSP DNAJA1 and a twofold decrease in levels of the de-ubiquitinating enzyme, UCHL1. After siRNA treatment, the expression of both genes was restored towards normal levels. To our knowledge, this is the first time that allele-specific silencing of mutant ataxin-7, targeting a common SNP, has been demonstrated in patient cells. These findings highlight the advantage of an allele-specific RNAi-based therapeutic approach, and indicate the value of primary patient-derived cells as useful models for mechanistic studies and for measuring efficacy of RNAi effectors on a patient-to-patient basis in the polyQ diseases. PMID:24667781

  20. A Look at Handling Qualities of Canard Configurations

    NASA Technical Reports Server (NTRS)

    Anderson, Seth B.

    1986-01-01

    The first human-powered flight was achieved by a canard-configured aircraft (Wright Brothers). Although other canard concepts were flown with varying degrees of success over the years, the tail-aft configuration has dominated the aircraft market for both military and civil use. Reviewed are the development of several canard aircraft with emphasis on stability and control, handling qualities, and operating problems. The results show that early canard concepts suffered adversely in flight behavior because of a lack of understanding of the sensitivities of these concepts to basic stability and control principles. Modern canard designs have been made competitive with tail-aft configurations by using appropriate handling qualities design criteria.

  1. RSRA flight control and stabilization. [Rotor Systems Research Aircraft

    NASA Technical Reports Server (NTRS)

    Linden, A. W.

    1976-01-01

    Handling qualities of the RSRA (rotor systems research aircraft), a special test vehicle with optional configurations (forewings, removable horizontal tailplanes, main rotor, tail rotor, and twin engines for forward flight all removable), are described. The aircraft can be fitted to fly as a conventional rotary-wing aircraft, fixed-wing aircraft, or compound helicopter, and is designed for testing existing and future rotor systems in flight. Controls include full-authority fly-by-wire controls and mechanical controls for rotary wing and for fixed wing. Stability augmentation, rotor test measurement systems, variable center of gravity capability, and rotor loading potential of the RSRA are also described.

  2. STS-66 Atlantis 747 SCA Ferry Flight Morning Takeoff for Delivery to Kennedy Space Center, Florida

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The space shuttle Atlantis atop NASA's 747 Shuttle Carrier Aircraft (SCA) during takeoff for a return ferry flight to the Kennedy Space Center from Edwards, California. The STS-66 mission was dedicated to the third flight of the Atmospheric Laboratory for Applications and Science-3 (ATLAS-3), part of NASA's Mission to Planet Earth program. The astronauts also deployed and retrieved a free-flying satellite designed to study the middle and lower thermospheres and perform a series of experiments covering life sciences research and microgravity processing. The landing was at 7:34 a.m. (PST) 14 November 1994, after being waved off from the Kennedy Space Center, Florida, due to adverse weather. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the

  3. Omnidirectional Actuator Handle

    NASA Technical Reports Server (NTRS)

    Moetteli, John B.

    1995-01-01

    Proposed actuator handle comprises two normally concentric rings, cables, and pulleys arranged such that relative displacement of rings from concentricity results in pulling of cable and consequent actuation of associated mechanism. Unlike conventional actuator handles like levers on farm implements, actuated from one or two directions only, proposed handle reached from almost any direction and actuated by pulling or pushing inner ring in any direction with respect to outer ring. Flanges installed on inner ring to cover gap between inner ring and housing to prevent clothing from being caught.

  4. Handling Pyrophoric Reagents

    SciTech Connect

    Alnajjar, Mikhail S.; Haynie, Todd O.

    2009-08-14

    Pyrophoric reagents are extremely hazardous. Special handling techniques are required to prevent contact with air and the resulting fire. This document provides several methods for working with pyrophoric reagents outside of an inert atmosphere.

  5. Helicopter Handling Qualities

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Helicopters are used by the military and civilian communities for a variety of tasks and must be capable of operating in poor weather conditions and at night. Accompanying extended helicopter operations is a significant increase in pilot workload and a need for better handling qualities. An overview of the status and problems in the development and specification of helicopter handling-qualities criteria is presented. Topics for future research efforts by government and industry are highlighted.

  6. Architecture Modeling and Performance Characterization of Space Communications and Navigation (SCaN) Network Using MACHETE

    NASA Technical Reports Server (NTRS)

    Jennings, Esther; Heckman, David

    2008-01-01

    As future space exploration missions will involve larger number of spacecraft and more complex systems, theoretical analysis alone may have limitations on characterizing system performance and interactions among the systems. Simulation tools can be useful for system performance characterization through detailed modeling and simulation of the systems and its environment...This paper reports the simulation of the Orion (Crew Exploration Vehicle) to the International Space Station (ISS) mission where Orion is launched by Ares into orbit on a 14-day mission to rendezvous with the ISS. Communications services for the mission are provided by the Space Communication and Navigation (SCaN) network infrastructure which includes the NASA Space Network (SN), Ground Network (GN) and NASA Integrated Services Network (NISN). The objectives of the simulation are to determine whether SCaN can meet the communications needs of the mission, to demonstrate the benefit of using QoS prioritization, and to evaluate network-key parameters of interest such as delay and throughout.

  7. Aircraft Electric Secondary Power

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Technologies resulted to aircraft power systems and aircraft in which all secondary power is supplied electrically are discussed. A high-voltage dc power generating system for fighter aircraft, permanent magnet motors and generators for aircraft, lightweight transformers, and the installation of electric generators on turbine engines are among the topics discussed.

  8. World commercial aircraft accidents

    SciTech Connect

    Kimura, C.Y.

    1993-01-01

    This report is a compilation of all accidents world-wide involving aircraft in commercial service which resulted in the loss of the airframe or one or more fatality, or both. This information has been gathered in order to present a complete inventory of commercial aircraft accidents. Events involving military action, sabotage, terrorist bombings, hijackings, suicides, and industrial ground accidents are included within this list. Included are: accidents involving world commercial jet aircraft, world commercial turboprop aircraft, world commercial pistonprop aircraft with four or more engines and world commercial pistonprop aircraft with two or three engines from 1946 to 1992. Each accident is presented with information in the following categories: date of the accident, airline and its flight numbers, type of flight, type of aircraft, aircraft registration number, construction number/manufacturers serial number, aircraft damage, accident flight phase, accident location, number of fatalities, number of occupants, cause, remarks, or description (brief) of the accident, and finally references used. The sixth chapter presents a summary of the world commercial aircraft accidents by major aircraft class (e.g. jet, turboprop, and pistonprop) and by flight phase. The seventh chapter presents several special studies including a list of world commercial aircraft accidents for all aircraft types with 100 or more fatalities in order of decreasing number of fatalities, a list of collision accidents involving commercial aircrafts, and a list of world commercial aircraft accidents for all aircraft types involving military action, sabotage, terrorist bombings, and hijackings.

  9. Ride quality sensitivity to SAS control law and to handling quality variations

    NASA Technical Reports Server (NTRS)

    Roberts, P. A.; Schmidt, D. K.; Swaim, R. L.

    1976-01-01

    The RQ trends which large flexible aircraft exhibit under various parameterizations of control laws and handling qualities are discussed. A summary of the assumptions and solution technique, a control law parameterization review, a discussion of ride sensitivity to handling qualities, and the RQ effects generated by implementing relaxed static stability configurations are included.

  10. Automatic control of an aircraft employing outboard horizontal stabilizers

    NASA Astrophysics Data System (ADS)

    Mukherjee, Jason S.

    2000-10-01

    This dissertation concerns the study of radio-operated control of an aircraft using fixed gain and adaptive controllers. The real-time feedback control system is developed to enhance the flying qualities of an experimental model aircraft. The non-conventional flight dynamics of the Outboard Horizontal Stabilizer (OHS) aircraft cause significant differences in the piloting of the aircraft. The control system was added to augment stability as well as to adjust the flight characteristics so that the OHS aircraft handles similar to a conventional aircraft. The control system design process, as applied to recent innovations in aircraft design, is followed. The Outboard Horizontal Stabilizer concept is a non-conventional aircraft, designed to take advantage of the normally wasted energy developed by the wing tip vortices. The research is based on a remotely-controlled OHS aircraft fitted with various sensors and telemetry as part of a real time feedback control system. Fixed gain Linear Quadratic controllers are first applied to the aircraft and result in a dramatic increase in performance at a nominal operating condition. Non-linearities in the OHS aircraft behavior and a wide operating range demanded the development of a variable gain adaptive controller utilizing a parameter estimation scheme to model the plant. The adaptive LQR gain-scheduled controller that emerged gave good performance over a wide flight envelope.

  11. Sca-1 expression defines developmental stages of mouse pDCs that show functional heterogeneity in the endosomal but not lysosomal TLR9 response.

    PubMed

    Niederquell, Marina; Kurig, Stefanie; Fischer, Jens A A; Tomiuk, Stefan; Swiecki, Melissa; Colonna, Marco; Johnston, Ian C D; Dzionek, Andrzej

    2013-11-01

    Plasmacytoid dendritic cells (pDCs) play an important role in innate and adaptive immunity and were shown to be identical to previously described natural interferon (IFN)-α-producing cells. Here, we describe two functionally distinct pDC subpopulations that are characterized by the differential expression of stem cell antigen-1 (Sca-1; Ly-6A/E). Sca-1(-) pDCs are mainly found in the BM, appear first during development, show a higher proliferative activity, and represent the more precursor phenotype. Sca-1(+) pDCs are mostly located in secondary lymphoid organs and represent a later developmental stage. Sca-1(-) pDCs give rise to an Sca-1(+) subset upon activation or in response to endogenous type I IFN. Interestingly, in contrast to Sca-1(-) pDCs, Sca-1(+) pDCs are defective in IFN-α production upon endosomal TLR9 stimulation, whereas lysosomal signaling via TLR9 is functional in both subsets. Gene expression analysis revealed that osteopontin is strongly upregulated in Sca-1(-) pDCs. These data provide evidence for the molecular basis of the observed functional heterogeneity, as the intracellular isoform of osteopontin couples TLR9 signaling to IFN-α expression. Taken together, our results indicate that Sca-1(-) pDCs are an early developmental stage of pDCs with distinct innate functions representing the true murine natural IFN-α-producing cells. PMID:23922217

  12. Generation of spinocerebellar ataxia type 3 patient-derived induced pluripotent stem cell line SCA3.A11.

    PubMed

    Hansen, Susanne K; Borland, Helena; Hasholt, Lis F; Tümer, Zeynep; Nielsen, Jørgen E; Rasmussen, Mikkel A; Nielsen, Troels T; Stummann, Tina C; Fog, Karina; Hyttel, Poul

    2016-05-01

    Spinocerebellar ataxia type 3 (SCA3) is a dominantly inherited neurodegenerative disease caused by a CAG-repeat expanding mutation in ATXN3. We generated induced pluripotent stem cells (iPSCs) from a SCA3 patient by electroporation of dermal fibroblasts with episomal plasmids encoding L-MYC, LIN28, SOX2, KLF4, OCT4 and short hairpin RNA targeting P53. The resulting iPSCs had normal karyotype, were free of genomically integrated episomal plasmids, expressed pluripotency markers, could differentiate into the three germ layers in vitro and retained the disease-causing ATXN3 mutation. This iPSC line could be useful for the investigation of SCA3 disease mechanisms. PMID:27346190

  13. Generation of spinocerebellar ataxia type 3 patient-derived induced pluripotent stem cell line SCA3.B11.

    PubMed

    Hansen, Susanne K; Borland, Helena; Hasholt, Lis F; Tümer, Zeynep; Nielsen, Jørgen E; Rasmussen, Mikkel A; Nielsen, Troels T; Stummann, Tina C; Fog, Karina; Hyttel, Poul

    2016-05-01

    Spinocerebellar ataxia type 3 (SCA3) is a dominantly inherited neurodegenerative disease caused by an expansion of the CAG-repeat in ATXN3. In this study, induced pluripotent stem cells (iPSCs) were generated from SCA3 patient dermal fibroblasts by electroporation with episomal plasmids encoding L-MYC, LIN28, SOX2, KLF4, OCT4 and short hairpin RNA targeting P53. The resulting iPSCs had normal karyotype, were free of integrated episomal plasmids, expressed pluripotency markers, could differentiate into the three germ layers in vitro and retained the disease-causing ATXN3 mutation. Potentially, this iPSC line could be a useful tool for the investigation of SCA3 disease mechanisms. PMID:27346191

  14. Long Term Performance Metrics of the GD SDR on the SCaN Testbed: The First Year on the ISS

    NASA Technical Reports Server (NTRS)

    Nappier, Jennifer; Wilson, Molly C.

    2014-01-01

    The General Dynamics (GD) S-Band software defined radio (SDR) in the Space Communications and Navigation (SCaN) Testbed on the International Space Station (ISS) provides experimenters an opportunity to develop and demonstrate experimental waveforms in space. The SCaN Testbed was installed on the ISS in August of 2012. After installation, the initial checkout and commissioning phases were completed and experimental operations commenced. One goal of the SCaN Testbed is to collect long term performance metrics for SDRs operating in space in order to demonstrate long term reliability. These metrics include the time the SDR powered on, the time the power amplifier (PA) is powered on, temperature trends, error detection and correction (EDAC) behavior, and waveform operational usage time. This paper describes the performance of the GD SDR over the first year of operations on the ISS.

  15. Effects of SCA40 on human isolated bronchus and human polymorphonuclear leukocytes: comparison with rolipram, SKF94120 and levcromakalim.

    PubMed Central

    Cortijo, J.; Villagrasa, V.; Navarrete, C.; Sanz, C.; Berto, L.; Michel, A.; Bonnet, P. A.; Morcillo, E. J.

    1996-01-01

    1. SCA40 (0.1 nM-0.1 mM) produced concentration-dependent suppression of the spontaneous tone of human isolated bronchus (-log EC50 = 6.85 +/- 0.09; n = 10) and reached a maximal relaxation similar to that of theophylline (3 mM). The potency (-log EC50 values) of SCA40 compared to other relaxants was rolipram (7.44 +/- 0.12; n = 9) > SCA40 > or = levcromakalim (6.49 +/- 0.04; n = 6) > SKF94120 (5.87 +/- 0.10; n = 9). 2. When tested against the activity of the isoenzymes of cyclic nucleotide phosphodiesterase (PDE) isolated from human bronchus, SCA40 proved highly potent against PDE III (-log IC50 = 6.47 +/- 0.16; n = 4). It was markedly less potent against PDE IV (4.82 +/- 0.18; n = 4) and PDE V (4.32 +/- 0.11; n = 4). 3. Human polymorphonuclear leukocytes (PMNs) stimulated with N-formylmethionyl-leucyl-phenylalanine (FMLP) produced a concentration-dependent superoxide anion generation and elastase release. SCA40 (1 nM-10 microM) produced a concentration-related inhibition of FMLP (30 nM approximately EC50)-induced superoxide production (-log IC50 = 5.48 +/- 0.10; n = 6) and elastase release (-log IC50 = 5.50 +/- 0.26; n = 6). Rolipram was an effective inhibitor of superoxide generation and elastase release (-log IC50 values approximately 8) while SKF94120 and levcromakalim were scarcely effective. 4. FMLP (30 nM) and thimerosal (20 microM) induced leukotriene B4 production and elevation of intracellular calcium concentration in human PMNs. The production of leukotriene B4 was inhibited by SCA40 in a concentration-related manner (-log IC50 = 5.94 +/- 0.22; n = 6) but SCA40 was less effective against the elevation of intracellular calcium. Rolipram was an effective inhibitor of leukotriene B4 synthesis (-log IC50 approximately 7) and intracellular calcium elevation (-log IC50 approximately 6) while SKF94120 and levcromakalim were scarcely effective. 5. It is concluded that SCA40 is an effective inhibitor of the inherent tone of human isolated bronchus. The

  16. Preliminary Validation of the Small Aircraft Transportation System Higher Volume Operations (SATS HVO) Concept

    NASA Technical Reports Server (NTRS)

    Williams, Daniel; Consiglio, Maria; Murdoch, Jennifer; Adams, Catherine

    2004-01-01

    This document provides a preliminary validation of the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept for normal conditions. Initial results reveal that the concept provides reduced air traffic delays when compared to current operations without increasing pilot workload. Characteristic to the SATS HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA) which would be activated by air traffic control (ATC) around designated non-towered, non-radar airports. During periods of poor visibility, SATS pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft in the SCA. Using onboard equipment and simple instrument flight procedures, they would then be better able to approach and land at the airport or depart from it. This concept would also require a new, ground-based automation system, typically located at the airport that would provide appropriate sequencing information to the arriving aircraft. Further validation of the SATS HVO concept is required and is the subject of ongoing research and subsequent publications.

  17. SPAR data handling utilities

    NASA Technical Reports Server (NTRS)

    Giles, G. L.; Haftka, R. T.

    1978-01-01

    The SPAR computer software system is a collection of processors that perform particular steps in the finite-element structural analysis procedure. The data generated by each processor are stored on a data base complex residing on an auxiliary storage device, and these data are then used by subsequent processors. The SPAR data handling utilities use routines to transfer data between the processors and the data base complex. A detailed description of the data base complex organization is presented. A discussion of how these SPAR data handling utilities are used in an application program to perform desired user functions is given with the steps necessary to convert an existing program to a SPAR processor by incorporating these utilities. Finally, a sample SPAR processor is included to illustrate the use of the data handling utilities.

  18. 41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Flight Safety Critical Aircraft Parts (FSCAP)? 102-36.345 Section 102-36.345 Public Contracts and... Requires Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety... appropriate Criticality Code on the SF 120, and ensure that all available historical and maintenance...

  19. 41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Flight Safety Critical Aircraft Parts (FSCAP)? 102-36.345 Section 102-36.345 Public Contracts and... Requires Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety... appropriate Criticality Code on the SF 120, and ensure that all available historical and maintenance...

  20. 41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Flight Safety Critical Aircraft Parts (FSCAP)? 102-36.345 Section 102-36.345 Public Contracts and... Requires Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety... appropriate Criticality Code on the SF 120, and ensure that all available historical and maintenance...

  1. 41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Flight Safety Critical Aircraft Parts (FSCAP)? 102-36.345 Section 102-36.345 Public Contracts and... Requires Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety... appropriate Criticality Code on the SF 120, and ensure that all available historical and maintenance...

  2. Rainfall Estimation over the Nile Basin using an Adapted Version of the SCaMPR Algorithm

    NASA Astrophysics Data System (ADS)

    Habib, E. H.; Kuligowski, R. J.; Elshamy, M. E.; Ali, M. A.; Haile, A.; Amin, D.; Eldin, A.

    2011-12-01

    Management of Egypt's Aswan High Dam is critical not only for flood control on the Nile but also for ensuring adequate water supplies for most of Egypt since rainfall is scarce over the vast majority of its land area. However, reservoir inflow is driven by rainfall over Sudan, Ethiopia, Uganda, and several other countries from which routine rain gauge data are sparse. Satellite-derived estimates of rainfall offer a much more detailed and timely set of data to form a basis for decisions on the operation of the dam. A single-channel infrared algorithm is currently in operational use at the Egyptian Nile Forecast Center (NFC). This study reports on the adaptation of a multi-spectral, multi-instrument satellite rainfall estimation algorithm (Self-Calibrating Multivariate Precipitation Retrieval, SCaMPR) for operational application over the Nile Basin. The algorithm uses a set of rainfall predictors from multi-spectral Infrared cloud top observations and self-calibrates them to a set of predictands from Microwave (MW) rain rate estimates. For application over the Nile Basin, the SCaMPR algorithm uses multiple satellite IR channels recently available to NFC from the Spinning Enhanced Visible and Infrared Imager (SEVIRI). Microwave rain rates are acquired from multiple sources such as SSM/I, SSMIS, AMSU, AMSR-E, and TMI. The algorithm has two main steps: rain/no-rain separation using discriminant analysis, and rain rate estimation using stepwise linear regression. We test two modes of algorithm calibration: real-time calibration with continuous updates of coefficients with newly coming MW rain rates, and calibration using static coefficients that are derived from IR-MW data from past observations. We also compare the SCaMPR algorithm to other global-scale satellite rainfall algorithms (e.g., 'Tropical Rainfall Measuring Mission (TRMM) and other sources' (TRMM-3B42) product, and the National Oceanographic and Atmospheric Administration Climate Prediction Center (NOAA

  3. FUEL HANDLING MECHANISM

    DOEpatents

    Koch, L.J.; Hutter, E.

    1960-02-01

    A remotely operable handling device specifically adapted for the handling of vertically disposed fuel rods in a nuclear reactor was developed. The device consists essentially of an elongated tubular member having a gripping device at the lower end of the pivoted jaw type adapted to grip an enlarged head on the upper end of the workpiece. The device includes a sensing element which engages the enlarged head and is displaced to remotely indicate when the workpiece is in the proper position to be engaged by the jaws.

  4. Safe Handling Practices

    NASA Technical Reports Server (NTRS)

    1980-01-01

    In 1977 Compugraphic Corporation was experiencing an unacceptable failure rate on microelectronic chips. Company engineers suspected that static electricity was causing the trouble because some electronic components are highly susceptible to damage by electrostatic charge. From a NASA Tech Brief, they learned that Rockwell International had prepared a report on safe handling practices for electronic components. NASA provided a Technical Support Package detailing 50 safe handling procedures affecting workers, work areas, equipment and packaging materials. Where poor practices were discovered, re-education of employees and other corrective measures were undertaken.

  5. SLUG HANDLING DEVICES

    DOEpatents

    Gentry, J.R.

    1958-09-16

    A device is described for handling fuel elements of a neutronic reactor. The device consists of two concentric telescoped contalners that may fit about the fuel element. A number of ratchet members, equally spaced about the entrance to the containers, are pivoted on the inner container and spring biased to the outer container so thnt they are forced to hear against and hold the fuel element, the weight of which tends to force the ratchets tighter against the fuel element. The ratchets are released from their hold by raising the inner container relative to the outer memeber. This device reduces the radiation hazard to the personnel handling the fuel elements.

  6. Immunomagnetic Separation of Fat Depot-Specific Sca1high Adipose-Derived Stem Cells (Ascs)

    PubMed Central

    Barnes, Richard H; Chun, Tae-Hwa

    2016-01-01

    The isolation of adipose-derived stem cells (ASCs) is an important method in the field of adipose tissue biology, adipogenesis, and extracellular matrix (ECM) remodeling. In vivo, ECM-rich environment consisting of fibrillar collagens provides a structural support to adipose tissues during the progression and regression of obesity. Physiological ECM remodeling mediated by matrix metalloproteinases (MMPs) plays a major role in regulating adipose tissue size and function1, 2. The loss of physiological collagenolytic ECM remodeling may lead to excessive collagen accumulation (tissue fibrosis), macrophage infiltration, and ultimately, a loss of metabolic homeostasis including insulin resistance3, 4. When a phenotypic change of the adipose tissue is observed in gene-targeted mouse models, isolating primary ASCs from fat depots for in vitro studies is an effective approach to define the role of the specific gene in regulating the function of ASCs. In the following, we define an immunomagnetic separation of Sca1high ASCs. PMID:27583550

  7. Novel neuronal cytoplasmic inclusions in a patient carrying SCA8 expansion mutation.

    PubMed

    Yokoyama, Teruo; Ishiyama, Miyako; Hasegawa, Kazuko; Uchihara, Toshiki; Yagishita, Saburo

    2014-02-01

    It has been reported that abnormal processing of pre-mRNA is caused by abnormal triplet expansion. Non-coding triplet expansions produce toxic RNA to alter RNA splicing activities. However, there has been no report on the globular RNA aggregation in neuronal cytoplasmic inclusions (NCIs) up to now. We herein report on an autopsy case (genetically determined as spinocerebellar atrophy 8 (SCA8)) with hitherto undescribed NCIs throughout the brain. NCIs were chiefly composed of small granular particles, virtually identical to ribosomes. Neurological features are comparable to the widespread lesions of the brain, including the spinal cord. Although 1C2-positivity of NCIs might be induced by reverse transcription of the CTG expansion, it remains to be clarified how abnormal aggregations of ribosome and extensive brain degeneration are related to the reverse or forward transcripts of the expanded repeat. PMID:23711133

  8. Immunomagnetic Separation of Fat Depot-specific Sca1high Adipose-derived Stem Cells (ASCs).

    PubMed

    Barnes, Richard H; Chun, Tae-Hwa

    2016-01-01

    The isolation of adipose-derived stem cells (ASCs) is an important method in the field of adipose tissue biology, adipogenesis, and extracellular matrix (ECM) remodeling. In vivo, ECM-rich environment consisting of fibrillar collagens provides a structural support to adipose tissues during the progression and regression of obesity. Physiological ECM remodeling mediated by matrix metalloproteinases (MMPs) plays a major role in regulating adipose tissue size and function(1,2). The loss of physiological collagenolytic ECM remodeling may lead to excessive collagen accumulation (tissue fibrosis), macrophage infiltration, and ultimately, a loss of metabolic homeostasis including insulin resistance(3,4). When a phenotypic change of the adipose tissue is observed in gene-targeted mouse models, isolating primary ASCs from fat depots for in vitro studies is an effective approach to define the role of the specific gene in regulating the function of ASCs. In the following, we define an immunomagnetic separation of Sca1(high) ASCs. PMID:27583550

  9. Propulsion controlled aircraft computer

    NASA Technical Reports Server (NTRS)

    Cogan, Bruce R. (Inventor)

    2010-01-01

    A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

  10. Grain Grading and Handling.

    ERIC Educational Resources Information Center

    Rendleman, Matt; Legacy, James

    This publication provides an introduction to grain grading and handling for adult students in vocational and technical education programs. Organized in five chapters, the booklet provides a brief overview of the jobs performed at a grain elevator and of the techniques used to grade grain. The first chapter introduces the grain industry and…

  11. Microforms in Information Handling.

    ERIC Educational Resources Information Center

    Williams, B. J. S.

    In an attempt to identify some of the factors which influence the utility of microforms as a medium for information handling, this report first traces some of the landmarks in the evolution of microforms since their invention in 1893. It next provides a factual account of current microform media and formats. The last section of the report contains…

  12. Benchmarks on automated system and software generation higher flexibility increased productivity and shorter time-to-market by ScaPable software

    NASA Astrophysics Data System (ADS)

    Gerlich, Rainer

    2002-07-01

    "ScaPable" is an acronym derived from "scalable" and "portable". The attribute "scalable" indicates that specific application software can automatically be built from scratch and verified without writing any statement in a programming language like C, thereby covering a large variety of embedded and/or distributed applications. The term "portable" addresses the capability to automatically port parts of such an application from one physical node to another one - the processor and operating system type may change - only requiring the names of the nodes, their processor type and operating system. This way the infrastructure of an embedded / distributed system can be built just by provision of literals and figures which define the system interaction, communication, topology and performance. Moreover, dedicated application software like needed for on-board command handling, data acquisition and processing, and telemetry handling can be built from generic templates. The generation time range from less than one second up to about twenty minutes on a PC/Linux platform (800 MHz). By this extremely short generation time risks can be identified early because the executable application is immediately available for validation. A rough estimation shows that one hour of automated system and software generation is equivalent to about 5 .. 50 man years. Currently, about 50% of a typical space embedded system can be covered by the available automated approach. However, the more it is applied, the more can be covered by automation. A system is constructed by applying a formal transformation to the few information as delivered by the user. This approach is not limited to the space domain, although the first industrial application was a space project. Quite different domains can take advantage of such principles of system construction. This paper explains the approach, compares it with other approaches, and provides figures on productivity, duration of system generation and reliability.

  13. Spinocerebellar ataxia type 2 (SCA2) in an Egyptian family presenting with polyphagia and marked CAG expansion in infancy.

    PubMed

    Abdel-Aleem, Alice; Zaki, Maha S

    2008-03-01

    We describe an Egyptian family having SCA2 affecting three generations with marked molecular and clinical anticipation observed in the index case. Our proband was a male child starting as early as 2 years old with progressive extrapyramidal manifestations, slow eye movements and cognitive impairment. A history of nonspecific mild developmental delay was recorded. The patient lost all cognitive functions, had persistent dystonic posture, trophic changes, vasomotor instability, dysphagia and died at the age of 7 years. The age at presentation among other affected family members varied between 11 and 45 years old across three generations. The early common neurological symptoms were choreoathetotic movements, myoclonic jerk, gait difficulty, expressionless face and emotional liability. Later, overt ataxia, incoordination, dysarthria, mild dementia and slow eye saccades predominated. Brisk tendon reflexes were detected in three cases. Peripheral nerve affection was a late manifestation. Interestingly, polyphagia and obesity were striking manifestations in the middle stage of the disease; an observation that might support a previously suggested relation between the ataxin-2 gene and body weight. The proband showed an amplified allele with marked CAG expansion in the form of a smear sized 69-75 repeats resulted from maternal transmission. To our knowledge, our index case is the second report in the literature presenting with infantile onset SCA2 and intermediate repeat expansion. This family expands the phenotypic spectrum of early onset SCA2 and points out the importance of considering SCA2 gene analysis in children with progressive neurological impairment and abnormal movements with or without polyphagia. PMID:18297329

  14. 50 CFR Figure 20 to Part 679 - Steller sea lion conservation area (SCA) of the Bering Sea

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Steller sea lion conservation area (SCA) of the Bering Sea 20 Figure 20 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 679, Fig. 20 Figure 20 to Part 679—Steller sea lion conservation...

  15. 50 CFR Figure 20 to Part 679 - Steller sea lion conservation area (SCA) of the Bering Sea

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Steller sea lion conservation area (SCA) of the Bering Sea 20 Figure 20 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 679, Fig. 20 Figure 20 to Part 679—Steller sea lion conservation...

  16. Oral zinc sulphate supplementation for six months in SCA2 patients: a randomized, double-blind, placebo-controlled trial.

    PubMed

    Velázquez-Pérez, Luis; Rodríguez-Chanfrau, Jorge; García-Rodríguez, Julio Cesar; Sánchez-Cruz, Gilberto; Aguilera-Rodríguez, Raúl; Rodríguez-Labrada, Roberto; Rodríguez-Díaz, Julio Cesar; Canales-Ochoa, Nalia; Gotay, Dennis Almaguer; Almaguer Mederos, Luis E; Laffita Mesa, José M; Porto-Verdecia, Marlene; Triana, Consuelo González; Pupo, Noemí Rodríguez; Batista, Idania Hidalgo; López-Hernandez, Orestes D; Polanco, Iverlis Díaz; Novas, Arelis Jayme

    2011-10-01

    Cuban patients with Spinocerebellar Ataxia type 2 (SCA2) have reduced concentrations of zinc in serum and cerebrospinal fluid (CSF). To assess the effect and safety of zinc supplementation, 36 Cuban SCA2 patients were randomly assigned to receive daily either 50 mg ZnSO(4) or placebo, together with neurorehabilitation therapy in a randomized, double-blind, placebo-controlled clinical trial during 6 months. Outcome measures included the changes of zinc levels in CSF and serum, ataxia score, oxidative stress and saccadic eye movements. At the end of the study, the Zinc-treated group showed: (i) a significant increase of the Zn levels in the CSF, (ii) mild decrease in the ataxia scale subscores for gait, posture, stance and dysdiadochocinesia (iii) reduction of lipid's oxidative damage, and (iv) reduction of saccadic latency when compared with the placebo group. The treatment was safe and well tolerated by all subjects. This study demonstrated the efficacy and safety of Zn supplementation, combined with neurorehabilitation for SCA2 patients and therefore it may encourage further studies on the clinical effect of zinc supplementation in SCA2 based in the conduction of future clinical trials with higher number of subjects. PMID:21562746

  17. 50 CFR Figure 20 to Part 679 - Steller sea lion conservation area (SCA) of the Bering Sea

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Steller sea lion conservation area (SCA) of the Bering Sea 20 Figure 20 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 679, Fig. 20 Figure 20 to Part 679—Steller sea lion conservation...

  18. 50 CFR Figure 20 to Part 679 - Steller sea lion conservation area (SCA) of the Bering Sea

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Steller sea lion conservation area (SCA) of the Bering Sea 20 Figure 20 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 679, Fig. 20 Figure 20 to Part 679—Steller sea lion conservation...

  19. 50 CFR Figure 20 to Part 679 - Steller sea lion conservation area (SCA) of the Bering Sea

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false Steller sea lion conservation area (SCA) of the Bering Sea 20 Figure 20 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 679, Fig. 20 Figure 20 to Part 679—Steller sea lion conservation...

  20. Pumilio1 Haploinsufficiency Leads to SCA1-like Neurodegeneration by Increasing Wild-Type Ataxin1 Levels

    PubMed Central

    Gennarino, Vincenzo A.; Singh, Ravi K.; White, Joshua J.; De Maio, Antonia; Han, Kihoon; Kim, Ji-Yoen; Jafar-Nejad, Paymaan; di Ronza, Alberto; Kang, Hyojin; Sayegh, Layal S.; Cooper, Thomas A.; Orr, Harry T.; Sillitoe, Roy V.; Zoghbi, Huda Y.

    2015-01-01

    SUMMARY Spinocerebellar ataxia type 1 (SCA1) is a paradigmatic neurodegenerative proteinopathy, in which a mutant protein (in this case, ATAXIN1) accumulates in neurons and exerts toxicity; in SCA1 this process causes progressive deterioration of motor coordination. Seeking to understand how post-translational modification of ATAXIN1 levels influences disease, we discovered that the RNA-binding protein PUMILIO1 (PUM1) not only directly regulates ATAXIN1 but that it also plays an unexpectedly important role in neuronal function. Loss of Pum1 caused progressive motor dysfunction and SCA1-like neurodegeneration with motor impairment, primarily by increasing Ataxin1 levels. Breeding Pum1+/− mice to SCA1 mice (Atxn1154Q/+) exacerbated disease progression, whereas breeding them to Atxn1+/− mice normalized Ataxin1 levels and largely rescued the Pum1+/− phenotype. Thus, both increased wild-type ATAXIN1 levels and PUM1 haploinsufficiency could contribute to human neurodegeneration. These results demonstrate the importance of studying post-transcriptional regulation of disease-driving proteins to reveal factors underlying neurodegenerative disease. PMID:25768905

  1. AIRCRAFT DEPAINTING TECHNOLOGY

    EPA Science Inventory

    Chemical paint strippers historically used for aircraft contained toxic and hazardous components; aircraft depainting operations are a major source of hazardous waste generation in DOD. Federal and state agencies have begun to restrict using these hazardous materials and Governme...

  2. Space Communications and Navigation (SCaN) Integrated Network Architecture Definition Document (ADD). Volume 1; Executive Summary; Revision 1

    NASA Technical Reports Server (NTRS)

    Younes, Badri A.; Schier, James S.

    2010-01-01

    The SCaN Program has defined an integrated network architecture that fully meets the Administrator s mandate to the Program, and will result in a NASA infrastructure capable of providing the needed and enabling communications services to future space missions. The integrated network architecture will increase SCaN operational efficiency and interoperability through standardization, commonality and technology infusion. It will enable NASA missions requiring advanced communication and tracking capabilities such as: a. Optical communication b. Antenna arraying c. Lunar and Mars Relays d. Integrated network management (service management and network control) and integrated service execution e. Enhanced tracking for navigation f. Space internetworking with DTN and IP g. End-to-end security h. Enhanced security services Moreover, the SCaN Program has created an Integrated Network Roadmap that depicts an orchestrated and coherent evolution path toward the target architecture, encompassing all aspects that concern network assets (i.e., operations and maintenance, sustaining engineering, upgrade efforts, and major development). This roadmap identifies major NASA ADPs, and shows dependencies and drivers among the various planned undertakings and timelines. The roadmap is scalable to accommodate timely adjustments in response to Agency needs, goals, objectives and funding. Future challenges to implementing this architecture include balancing user mission needs, technology development, and the availability of funding within NASA s priorities. Strategies for addressing these challenges are to: define a flexible architecture, update the architecture periodically, use ADPs to evaluate options and determine when to make decisions, and to engage the stakeholders in these evaluations. In addition, the SCaN Program will evaluate and respond to mission need dates for technical and operational capabilities to be provided by the SCaN integrated network. In that regard, the architecture

  3. SCA15 due to large ITPR1 deletions in a cohort of 333 Caucasian families with dominant ataxia

    PubMed Central

    Marelli, Cecilia; van de Leemput, Joyce; Johnson, Janel O; Tison, Francois; Thauvin-Robinet, Christel; Picard, Fabienne; Tranchant, Christine; Hernandez, Dena G; Huttin, Bernard; Boulliat, Jacques; Sangla, Iban; Marescaux, Christian; Brique, Serge; Dollfus, Hélène; Arepalli, Sampath; Benatru, Isabelle; Ollagnon, Elisabeth; Forlani, Sylvie; Hardy, John; Stevanin, Giovanni; Dürr, Alexandra; Singleton, Andrew; Brice, Alexis

    2011-01-01

    Objectives to determine the frequency and the phenotypical spectrum of SCA15 patients. Methods in the index cases of 333 families with autosomal dominant cerebellar ataxia (ADCA) negative for CAG repeat expansions in coding exons (SCA1,2,3,6,7,17 and dentatorubropallidoluysian atrophy), we searched for heterozygous rearrangements in ITPR1. Taqman PCR (258 index cases) or SNP genome-wide genotyping (75 index cases) were used. Results a deletion of ITPR1 was found in 6/333 (1.8%) families, corresponding to 13 SCA15 patients. Age at onset ranged from 18 to 66 years with a mean of 35±16 years. The symptom at onset was mainly cerebellar gait ataxia, except for one patient presenting with isolated upper limb tremor. Although we tested a large cohort of families irrespective of their phenotype, the main clinical features of SCA15 patients were homogeneous and characterized by a very slowly progressive gait and limb cerebellar ataxia with dysarthria. However, pyramidal signs (two patients), and mild cognitive problems (two patients) were occasionally present. Ocular alterations consisted of nystagmus, mainly horizontal and gaze-evoked (ten patients), and saccadic pursuit (seven patients). Radiological findings showed global or predominant vermian cerebellar atrophy in all patients. Conclusions In this series ITPR1 deletions are rare and account for ~1% of all ADCA. The SCA15 phenotype mostly consists of a slowly progressive isolated cerebellar ataxia with variable age at onset; an additional pyramidal syndrome and problems in executive functions may be present in a minority of patients. PMID:21555639

  4. Historical overview of V/STOL aircraft technology

    NASA Technical Reports Server (NTRS)

    Anderson, S. B.

    1981-01-01

    The requirements for satisfactory characteristics in several key technology areas are discussed and a review is made of various V/STOL aircraft for the purpose of assessing the success or failure of each design in meeting design requirements. Special operating techniques were developed to help circumvent deficiencies. For the most part performance and handling qualities limitations restricted operational evaluations. Flight operations emphasized the need for good STOL performance, good handling qualities, and stability and control augmentation. The majority of aircraft suffered adverse ground effects.

  5. Aircraft noise problems

    NASA Astrophysics Data System (ADS)

    1981-01-01

    The problems related to aircraft noise were studied. Physical origin (sound), human reaction (noise), quantization of noise and sound sources of aircraft noise are discussed. Noise abatement at the source, technical, fleet-political and air traffic measures are explained. The measurements and future developments are also discussed. The position of Lufthansa as regards aircraft noise problems is depicted.

  6. Unmanned aircraft systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned platforms have become increasingly more common in recent years for acquiring remotely sensed data. These aircraft are referred to as Unmanned Airborne Vehicles (UAV), Remotely Piloted Aircraft (RPA), Remotely Piloted Vehicles (RPV), or Unmanned Aircraft Systems (UAS), the official term used...

  7. Plutonium Immobilization Puck Handling

    SciTech Connect

    Kriikku, E.

    1999-01-26

    The Plutonium Immobilization Project (PIP) will immobilize excess plutonium and store the plutonium in a high level waste radiation field. To accomplish these goals, the PIP will process various forms of plutonium into plutonium oxide, mix the oxide powder with ceramic precursors, press the mixture into pucks, sinter the pucks into a ceramic puck, load the pucks into metal cans, seal the cans, load the cans into magazines, and load the magazines into a Defense Waste Processing Facility (DPWF) canister. These canisters will be sent to the DWPF, an existing Savannah River Site (SRS) facility, where molten high level waste glass will be poured into the canisters encapsulating the ceramic pucks. Due to the plutonium radiation, remote equipment will perform these operations in a contained environment. The Plutonium Immobilization Project is in the early design stages and the facility will begin operation in 2005. This paper will discuss the Plutonium Immobilization puck handling conceptual design and the puck handling equipment testing.

  8. A PARENTAL HANDLING QUESTIONNAIRE

    PubMed Central

    Malhotra, Savita

    1990-01-01

    SUMMMARY Parental Care and Control, which are two major parental handling, variables are significantly related to psychological morbidity in children where high care-low control is associated with healthy development and low care-high control is related to psychiatric disorder. Parents by & large do not differ in their patterns of handling with regard to age and sex of the child, rural-urban living and SES except that younger children are given more care and those from high SES exercise less control among normal children. However, low care for younger children, high control for older children; low care and high control for males, rural background and higher SES families was associated with psychiatric morbidity in children. PMID:21927469

  9. Solid waste handling

    SciTech Connect

    Parazin, R.J.

    1995-05-31

    This study presents estimates of the solid radioactive waste quantities that will be generated in the Separations, Low-Level Waste Vitrification and High-Level Waste Vitrification facilities, collectively called the Tank Waste Remediation System Treatment Complex, over the life of these facilities. This study then considers previous estimates from other 200 Area generators and compares alternative methods of handling (segregation, packaging, assaying, shipping, etc.).

  10. Space shuttle handling qualities

    NASA Technical Reports Server (NTRS)

    Gilbert, D. W.

    1985-01-01

    The initial Orbiter handling qualities requirements, their effect on the vehicle design, and how it all turned out through the first six orbital missions are reviewed. Specific areas consisting of hand controller considerations and the wheelie problem are discussed. The requirements for the pitch axis subsonic flight control system are reviewed. Results of recent simulator evaluations to compare the existing system at landing with several other configurations are presented.

  11. Uranium hexafluoride handling. Proceedings

    SciTech Connect

    Not Available

    1991-12-31

    The United States Department of Energy, Oak Ridge Field Office, and Martin Marietta Energy Systems, Inc., are co-sponsoring this Second International Conference on Uranium Hexafluoride Handling. The conference is offered as a forum for the exchange of information and concepts regarding the technical and regulatory issues and the safety aspects which relate to the handling of uranium hexafluoride. Through the papers presented here, we attempt not only to share technological advances and lessons learned, but also to demonstrate that we are concerned about the health and safety of our workers and the public, and are good stewards of the environment in which we all work and live. These proceedings are a compilation of the work of many experts in that phase of world-wide industry which comprises the nuclear fuel cycle. Their experience spans the entire range over which uranium hexafluoride is involved in the fuel cycle, from the production of UF{sub 6} from the naturally-occurring oxide to its re-conversion to oxide for reactor fuels. The papers furnish insights into the chemical, physical, and nuclear properties of uranium hexafluoride as they influence its transport, storage, and the design and operation of plant-scale facilities for production, processing, and conversion to oxide. The papers demonstrate, in an industry often cited for its excellent safety record, continuing efforts to further improve safety in all areas of handling uranium hexafluoride. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

  12. Subsonic Wing Optimization for Handling Qualities Using ACSYNT

    NASA Technical Reports Server (NTRS)

    Soban, Danielle Suzanne

    1996-01-01

    The capability to accurately and rapidly predict aircraft stability derivatives using one comprehensive analysis tool has been created. The PREDAVOR tool has the following capabilities: rapid estimation of stability derivatives using a vortex lattice method, calculation of a longitudinal handling qualities metric, and inherent methodology to optimize a given aircraft configuration for longitudinal handling qualities, including an intuitive graphical interface. The PREDAVOR tool may be applied to both subsonic and supersonic designs, as well as conventional and unconventional, symmetric and asymmetric configurations. The workstation-based tool uses as its model a three-dimensional model of the configuration generated using a computer aided design (CAD) package. The PREDAVOR tool was applied to a Lear Jet Model 23 and the North American XB-70 Valkyrie.

  13. Simulation of Aircraft Behaviour on and Close to the Ground

    NASA Technical Reports Server (NTRS)

    Barnes, A. G.; Yager, T. J.

    1985-01-01

    A guide to the current state of the technology of simulating fixed-wing aircraft handling qualities and performance on or close to the ground is presented and pitfalls which may prevent an adequate implementation are indicated. The scope of possible applications in both aircraft design work and pilot training is considered and the requirements for mathematical model definitions and implementations are discussed. The current requirements for visual and motion systems, cockpit cueing, and software modelling are also reviewed, and illustrated with specific examples in areas of aircraft research and development studies and pilot training uses. Needs for further improvements and additional data acquisition are identified.

  14. A methodology for designing aircraft to low sonic boom constraints

    NASA Technical Reports Server (NTRS)

    Mack, Robert J.; Needleman, Kathy E.

    1991-01-01

    A method for designing conceptual supersonic cruise aircraft to meet low sonic boom requirements is outlined and described. The aircraft design is guided through a systematic evolution from initial three view drawing to a final numerical model description, while the designer using the method controls the integration of low sonic boom, high supersonic aerodynamic efficiency, adequate low speed handling, and reasonable structure and materials technologies. Some experience in preliminary aircraft design and in the use of various analytical and numerical codes is required for integrating the volume and lift requirements throughout the design process.

  15. A Risk Management Architecture for Emergency Integrated Aircraft Control

    NASA Technical Reports Server (NTRS)

    McGlynn, Gregory E.; Litt, Jonathan S.; Lemon, Kimberly A.; Csank, Jeffrey T.

    2011-01-01

    Enhanced engine operation--operation that is beyond normal limits--has the potential to improve the adaptability and safety of aircraft in emergency situations. Intelligent use of enhanced engine operation to improve the handling qualities of the aircraft requires sophisticated risk estimation techniques and a risk management system that spans the flight and propulsion controllers. In this paper, an architecture that weighs the risks of the emergency and of possible engine performance enhancements to reduce overall risk to the aircraft is described. Two examples of emergency situations are presented to demonstrate the interaction between the flight and propulsion controllers to facilitate the enhanced operation.

  16. Application of Active Controls Technology to Aircraft Ride Smoothing Systems

    NASA Technical Reports Server (NTRS)

    Lapins, Maris; Jacobson, Ira D.

    1975-01-01

    A critical review of past efforts in the design and testing of ride smoothing and gust alleviation systems is presented. Design trade-offs involving sensor types, choice of feedback loops, human comfort and aircraft handling-qualities criteria are discussed. Synthesis of a system designed to employ direct-lift and side-force producing surfaces is reported. Two STOL-class aircraft and an executive transport are considered. Theoretically-predicted system performance is compared with hybrid simulation and flight test data. Pilot opinion rating, pilot workload, and passenger comfort rating data for the basic and augmented aircraft are included.

  17. Application of active controls technology to aircraft bide smoothing systems

    NASA Technical Reports Server (NTRS)

    Lapins, M.; Jacobson, I. D.

    1975-01-01

    A critical review of past efforts in the design and testing of ride smoothing and gust alleviation systems is presented. Design trade offs involving sensor types, choice of feedback loops, human comfort, and aircraft handling-qualities criteria are discussed. Synthesis of a system designed to employ direct-lift and side-force producing surfaces is reported. Two STOL aircraft and an executive transport are considered. Theoretically predicted system performance is compared with hybrid simulation and flight test data. Pilot opinion rating, pilot workload, and passenger comfort rating data for the basic and augmented aircraft are included.

  18. Small Aircraft Transportation System, Higher Volume Operations Concept: Normal Operations

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.; Jones, Kenneth M.; Consiglio, Maria C.; Williams, Daniel M.; Adams, Catherine A.

    2004-01-01

    This document defines the Small Aircraft Transportation System (SATS), Higher Volume Operations (HVO) concept for normal conditions. In this concept, a block of airspace would be established around designated non-towered, non-radar airports during periods of poor weather. Within this new airspace, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Using onboard equipment and procedures, they would then approach and land at the airport. Departures would be handled in a similar fashion. The details for this operational concept are provided in this document.

  19. Aircraft landing gear systems

    NASA Technical Reports Server (NTRS)

    Tanner, John A. (Editor)

    1990-01-01

    Topics presented include the laboratory simulation of landing gear pitch-plane dynamics, a summary of recent aircraft/ground vehicle friction measurement tests, some recent aircraft tire thermal studies, and an evaluation of critical speeds in high-speed aircraft. Also presented are a review of NASA antiskid braking research, titanium matrix composite landing gear development, the current methods and perspective of aircraft flotation analysis, the flow rate and trajectory of water spray produced by an aircraft tire, and spin-up studies of the Space Shuttle Orbiter main gear tire.

  20. Advanced Information Processing System - Fault detection and error handling

    NASA Technical Reports Server (NTRS)

    Lala, J. H.

    1985-01-01

    The Advanced Information Processing System (AIPS) is designed to provide a fault tolerant and damage tolerant data processing architecture for a broad range of aerospace vehicles, including tactical and transport aircraft, and manned and autonomous spacecraft. A proof-of-concept (POC) system is now in the detailed design and fabrication phase. This paper gives an overview of a preliminary fault detection and error handling philosophy in AIPS.

  1. Shuttle Atlantis in Mate-Demate Device Being Loaded onto SCA-747 for Return to Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This photo shows a night view of the orbiter Atlantis being loaded onto one of NASA's Boeing 747 Shuttle Carrier Aircraft (SCA) at the Dryden Flight Research Center, Edwards, California. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and can be reused on future flights. Some of these orbital laboratories, like the Spacelab, provide facilities for several specialists to conduct experiments in such fields as medicine, astronomy, and materials manufacturing. Some types of satellites deployed by Space Shuttles include those involved in environmental and resources protection, astronomy, weather forecasting, navigation, oceanographic studies, and other scientific fields

  2. Ataxin-2 regulates RGS8 translation in a new BAC-SCA2 transgenic mouse model.

    PubMed

    Dansithong, Warunee; Paul, Sharan; Figueroa, Karla P; Rinehart, Marc D; Wiest, Shaina; Pflieger, Lance T; Scoles, Daniel R; Pulst, Stefan M

    2015-04-01

    Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant disorder with progressive degeneration of cerebellar Purkinje cells (PCs) and other neurons caused by expansion of a glutamine (Q) tract in the ATXN2 protein. We generated BAC transgenic lines in which the full-length human ATXN2 gene was transcribed using its endogenous regulatory machinery. Mice with the ATXN2 BAC transgene with an expanded CAG repeat (BAC-Q72) developed a progressive cellular and motor phenotype, whereas BAC mice expressing wild-type human ATXN2 (BAC-Q22) were indistinguishable from control mice. Expression analysis of laser-capture microdissected (LCM) fractions and regional expression confirmed that the BAC transgene was expressed in PCs and in other neuronal groups such as granule cells (GCs) and neurons in deep cerebellar nuclei as well as in spinal cord. Transcriptome analysis by deep RNA-sequencing revealed that BAC-Q72 mice had progressive changes in steady-state levels of specific mRNAs including Rgs8, one of the earliest down-regulated transcripts in the Pcp2-ATXN2[Q127] mouse line. Consistent with LCM analysis, transcriptome changes analyzed by deep RNA-sequencing were not restricted to PCs, but were also seen in transcripts enriched in GCs such as Neurod1. BAC-Q72, but not BAC-Q22 mice had reduced Rgs8 mRNA levels and even more severely reduced steady-state protein levels. Using RNA immunoprecipitation we showed that ATXN2 interacted selectively with RGS8 mRNA. This interaction was impaired when ATXN2 harbored an expanded polyglutamine. Mutant ATXN2 also reduced RGS8 expression in an in vitro coupled translation assay when compared with equal expression of wild-type ATXN2-Q22. Reduced abundance of Rgs8 in Pcp2-ATXN2[Q127] and BAC-Q72 mice supports our observations of a hyper-excitable mGluR1-ITPR1 signaling axis in SCA2, as RGS proteins are linked to attenuating mGluR1 signaling. PMID:25902068

  3. SCA2 predictive testing in Cuba: challenging concepts and protocol evolution.

    PubMed

    Cruz-Mariño, Tania; Vázquez-Mojena, Yaimeé; Velázquez-Pérez, Luis; González-Zaldívar, Yanetza; Aguilera-Rodríguez, Raúl; Velázquez-Santos, Miguel; Estupiñán-Rodríguez, Annelié; Laffita-Mesa, José Miguel; Almaguer-Mederos, Luis E; Paneque, Milena

    2015-07-01

    Spinocerebellar ataxia type 2 (SCA2) is a neurodegenerative disease caused by a CAG repeat expansion in the ATXN2 gene. Cuba has the highest prevalence (6.57 cases/10(5) inhabitants) of SCA2 in the world. The existence of 753 affected individuals and 7173 relatives at risk prompted the development in 2001 of the first predictive testing program in the country. The medical records of over 1193 individuals, who requested the test within a 13-year period, were analyzed retrospectively. The presymptomatic and the prenatal tests had uptake rates of 43.4 and 23.9 %, respectively. Several ethical challenges resulted from this program. These include the following: (1) withdrawal due to the initial protocol's length; (2) the request to participate by 16 at-risk adolescents; (3) the decision made by ten out of 33 couples with a test-positive fetus to carry the pregnancy to term, leading to de facto predictive testing of minors; (4) the elevated frequency of the ATXN2 gene large normal alleles (≥23 to 31 repeats) in the reference population. These issues have led to major changes in the guidelines of the predictive testing protocol: (1) the protocol length was shortened; (2) the inclusion criteria were expanded to reach at-risk adolescents with an interest in prenatal diagnosis; (3) interdisciplinary follow-up was offered to families in which test-positive fetuses were not aborted; (4) prenatal testing was made available to carriers of large normal alleles with ≥27 CAG repeats. The profiles of the participants were similar to those reported for other predictive testing programs for conditions like Huntington disease and familial adenomatous polyposis. The genetic counseling practices at the community level, the ample health education provided to the at-risk population, together with multidisciplinary and specialized attention to the affected families, are lessons from the Cuban experience that can be relevant for other international teams conducting predictive testing

  4. Small transport aircraft technology

    NASA Technical Reports Server (NTRS)

    Williams, L. J.

    1983-01-01

    Information on commuter airline trends and aircraft developments is provided to upgrade the preliminary findings of a NASA-formed small transport aircraft technology (STAT) team, established to determine whether the agency's research and development programs could help commuter aircraft manufacturers solve technical problems related to passenger acceptance and use of 19- to 50-passenger aircraft. The results and conclusions of the full set of completed STAT studies are presented. These studies were performed by five airplane manufacturers, five engine manufacturers, and two propeller manufacturers. Those portions of NASA's overall aeronautics research and development programs which are applicable to commuter aircraft design are summarized. Areas of technology that might beneficially be expanded or initiated to aid the US commuter aircraft manufacturers in the evolution of improved aircraft for the market are suggested.

  5. A review on bicycle and motorcycle rider control with a perspective on handling qualities

    NASA Astrophysics Data System (ADS)

    Kooijman, J. D. G.; Schwab, A. L.

    2013-11-01

    This paper is a review study on handling and control of bicycles and motorcycles, the so-called single-track vehicles. The first part gives a brief overview on the modelling of the dynamics of single-track vehicles and the experimental validation. The second part focusses on a review of modelling and measuring human rider control. The third part deals with the concepts of handling and manoeuvrability and their experimental validation. Parallels are drawn with the literature on aircraft handling and pilot models. The paper concludes with the open ends and promising directions for future work in the field of handling and control of single-track vehicles.

  6. Solid handling valve

    DOEpatents

    Williams, William R.

    1979-01-01

    The present invention is directed to a solids handling valve for use in combination with lock hoppers utilized for conveying pulverized coal to a coal gasifier. The valve comprises a fluid-actuated flow control piston disposed within a housing and provided with a tapered primary seal having a recessed seat on the housing and a radially expandable fluid-actuated secondary seal. The valve seals are highly resistive to corrosion, erosion and abrasion by the solids, liquids, and gases associated with the gasification process so as to minimize valve failure.

  7. Students' Strategies for Exception Handling

    ERIC Educational Resources Information Center

    Rashkovits, Rami; Lavy, Ilana

    2011-01-01

    This study discusses and presents various strategies employed by novice programmers concerning exception handling. The main contributions of this paper are as follows: we provide an analysis tool to measure the level of assimilation of exception handling mechanism; we present and analyse strategies to handle exceptions; we present and analyse…

  8. Crystallographic and Computational Analyses of AUUCU Repeating RNA That Causes Spinocerebellar Ataxia Type 10 (SCA10).

    PubMed

    Park, HaJeung; González, Àlex L; Yildirim, Ilyas; Tran, Tuan; Lohman, Jeremy R; Fang, Pengfei; Guo, Min; Disney, Matthew D

    2015-06-23

    Spinocerebellar ataxia type 10 (SCA10) is caused by a pentanucleotide repeat expansion of r(AUUCU) within intron 9 of the ATXN10 pre-mRNA. The RNA causes disease by a gain-of-function mechanism in which it inactivates proteins involved in RNA biogenesis. Spectroscopic studies showed that r(AUUCU) repeats form a hairpin structure; however, there were no high-resolution structural models prior to this work. Herein, we report the first crystal structure of model r(AUUCU) repeats refined to 2.8 Å and analysis of the structure via molecular dynamics simulations. The r(AUUCU) tracts adopt an overall A-form geometry in which 3 × 3 nucleotide (5')UCU(3')/(3')UCU(5') internal loops are closed by AU pairs. Helical parameters of the refined structure as well as the corresponding electron density map on the crystallographic model reflect dynamic features of the internal loop. The computational analyses captured dynamic motion of the loop closing pairs, which can form single-stranded conformations with relatively low energies. Overall, the results presented here suggest the possibility for r(AUUCU) repeats to form metastable A-from structures, which can rearrange into single-stranded conformations and attract proteins such as heterogeneous nuclear ribonucleoprotein K (hnRNP K). The information presented here may aid in the rational design of therapeutics targeting this RNA. PMID:26039897

  9. Time Distribution Using SpaceWire in the SCaN Testbed on ISS

    NASA Technical Reports Server (NTRS)

    Lux, James P.

    2012-01-01

    A paper describes an approach for timekeeping and time transfer among the devices on the CoNNeCT project s SCaN Testbed. It also describes how the clocks may be synchronized with an external time reference; e.g., time tags from the International Space Station (ISS) or RF signals received by a radio (TDRSS time service or GPS). All the units have some sort of counter that is fed by an oscillator at some convenient frequency. The basic problem in timekeeping is relating the counter value to some external time standard such as UTC. With SpaceWire, there are two approaches possible: one is to just use SpaceWire to send a message, and use an external wire for the sync signal. This is much the same as with the RS- 232 messages and l pps line from a GPS receiver. However, SpaceWire has an additional capability that was added to make it easier - it can insert and receive a special "timecode" word in the data stream.

  10. Cerebellar Transcriptome Profiles of ATXN1 Transgenic Mice Reveal SCA1 Disease Progression and Protection Pathways.

    PubMed

    Ingram, Melissa; Wozniak, Emily A L; Duvick, Lisa; Yang, Rendong; Bergmann, Paul; Carson, Robert; O'Callaghan, Brennon; Zoghbi, Huda Y; Henzler, Christine; Orr, Harry T

    2016-03-16

    SCA1, a fatal neurodegenerative disorder, is caused by a CAG expansion encoding a polyglutamine stretch in the protein ATXN1. We used RNA sequencing to profile cerebellar gene expression in Pcp2-ATXN1[82Q] mice with ataxia and progressive pathology and Pcp2-ATXN1[30Q]D776 animals having ataxia in absence of Purkinje cell progressive pathology. Weighted Gene Coexpression Network Analysis of the cerebellar expression data revealed two gene networks that significantly correlated with disease and have an expression profile correlating with disease progression in ATXN1[82Q] Purkinje cells. The Magenta Module provides a signature of suppressed transcriptional programs reflecting disease progression in Purkinje cells, while the Lt Yellow Module reflects transcriptional programs activated in response to disease in Purkinje cells as well as other cerebellar cell types. Furthermore, we found that upregulation of cholecystokinin (Cck) and subsequent interaction with the Cck1 receptor likely underlies the lack of progressive Purkinje cell pathology in Pcp2-ATXN1[30Q]D776 mice. PMID:26948890

  11. Crystallographic and Computational Analyses of AUUCU Repeating RNA That Causes Spinocerebellar Ataxia Type 10 (SCA10)

    PubMed Central

    Park, HaJeung; González, Àlex L.; Yildirim, Ilyas; Tran, Tuan; Lohman, Jeremy R.; Fang, Pengfei; Guo, Min; Disney, Matthew D.

    2016-01-01

    Spinocerebellar ataxia type 10 (SCA10) is caused by a pentanucleotide repeat expansion of r(AUUCU) within intron 9 of the ATXN10 pre-mRNA. The RNA causes disease by a gain-of-function mechanism in which it inactivates proteins involved in RNA biogenesis. Spectroscopic studies showed that r(AUUCU) repeats form a hairpin structure; however, there were no high-resolution structural models prior to this work. Herein, we report the first crystal structure of model r(AUUCU) repeats refined to 2.8 Å and analysis of the structure via molecular dynamics simulations. The r(AUUCU) tracts adopt an overall A-form geometry in which 3 × 3 nucleotide 5′UCU3′/3′UCU5′ internal loops are closed by AU pairs. Helical parameters of the refined structure as well as the corresponding electron density map on the crystallographic model reflect dynamic features of the internal loop. The computational analyses captured dynamic motion of the loop closing pairs, which can form single-stranded conformations with relatively low energies. Overall, the results presented here suggest the possibility for r(AUUCU) repeats to form metastable A-from structures, which can rearrange into single-stranded conformations and attract proteins such as heterogeneous nuclear ribonucleoprotein K (hnRNP K). The information presented here may aid in the rational design of therapeutics targeting this RNA. PMID:26039897

  12. Tom McMurtry - chief of Dryden Flight Operations with STS mated to 747 SCA

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Thomas C. McMurtry in front of the 747 Shuttle Carrier Aircraft. He graduated in June 1957 from the University of Notre Dame with a Bachelor of Science degree in Mechanical Engineering. McMurtry had been part of the university's Navy ROTC program, and after graduation he joined the Navy as a pilot. Before retiring from the Navy in 1964 as a Lieutenant, he graduated from the U.S. Navy Test Pilot School, and had flown such aircraft as the F9F, A3D, A4D, F3D, F-8, A-6, and S-2. McMurtry was then a consultant for the Lockheed Corporation until joining NASA as a research pilot in 1967. While at the Dryden Flight Research Center, he was co-project pilot on the F-8 Digital Fly-By-Wire program, and the 747 Shuttle Carrier Aircraft, as well as project pilot on the F-15 Digital Electronic Engine Control (DEEC) project, the KC-135 Winglets, the F-8 Supercritical Wing project, and the AD-1 Oblique Wing Project. He also made research flights in NASA's YF-12C aircraft (actually a modified SR-71). McMurtry made the last glide flight of the X-24B lifting body on November 26, 1975, and was co-pilot of the 747 Shuttle Carrier Aircraft on the first free flight of the space shuttle Enterprise on August 12, 1977. He was involved in several remotely piloted research vehicle programs, including the FAA/NASA 720 Controlled Impact Demonstration and the 3/8 F-15 Spin Research Vehicle. During McMurtry's 32 years as a pilot and manager at Dryden, he received numerous awards. These include the NASA Exceptional Service Award for his work on the F-8 Supercritical Wing, and the Iven C. Kincheloe Award from the Society of Experimental Test Pilots for his role as chief pilot on the AD-1 project, the NASA Distinguished Service Medal, and the 1999 Milton O. Thomson Lifetime Achievement Award. McMurtry also held a number of management positions at Dryden, including Chief Pilot, Director of Flight Operations, Associate Director of Flight Operations, and was the acting Chief Engineer at the time of his

  13. Console test report for shuttle task 501 shuttle carrier aircraft transceiver console (SED 36115353-301)

    NASA Technical Reports Server (NTRS)

    Lane, J. H.

    1976-01-01

    Performance tests completed on the Space Shuttle Carrier Aircraft (SCA) transceiver console, verifying its design objectives, were described. These tests included: (1) check of power supply voltages for correct output voltage and energization at the proper point in the turn on sequence, (2) check of cooling system (LRU blower, overload sensors and circuitry, and thermocouple probe), (3) check of control circuits logic, including the provisions for remote control and display, (4) check of the LRU connector for presence of correct voltages and absence of incorrect voltages under both energized and deenergized conditions, and (5) check of the AGC and power output monitor circuits.

  14. Sectional device handling tool

    DOEpatents

    Candee, Clark B.

    1988-07-12

    Apparatus for remotely handling a device in an irradiated underwater environment includes a plurality of tubular sections interconnected end-to-end to form a handling structure, the bottom section being adapted for connection to the device. A support section is connected to the top tubular section and is adapted to be suspended from an overhead crane. Each section is flanged at its opposite ends. Axially retractable bolts in each bottom flange are threadedly engageable with holes in the top flange of an adjacent section, each bolt being biased to its retracted position and retained in place on the bottom flange. Guide pins on each top flange cooperate with mating holes on adjacent bottom flanges to guide movement of the parts to the proper interconnection orientation. Each section carries two hydraulic line segments provided with quick-connect/disconnect fittings at their opposite ends for connection to the segments of adjacent tubular sections upon interconnection thereof to form control lines which are connectable to the device and to an associated control console.

  15. A new variable phenotype in spinocerebellar ataxia 27 (SCA 27) caused by a deletion in the FGF14 gene.

    PubMed

    Coebergh, J A; Fransen van de Putte, D E; Snoeck, I N; Ruivenkamp, C; van Haeringen, A; Smit, L M

    2014-05-01

    We present a young boy whose mild ataxia and abnormal eye movements repeatedly deteriorated with fever, making him unable to sit or walk during fever episodes. SNP-array analysis identified a 202 kb deletion in chromosome 13q33.1 containing the fibroblast growth factor (FGF)14 gene, which is associated with spinocerebellar ataxia (SCA) 27. This 13q deletion was also present in the proband's mother and grandmother. The mother was unable to perform tandem gait walking and had abnormal eye movements but had never sought medical attention. The grandmother predominantly had a postural tremor. FGF14 regulates brain sodium channels, especially in the cerebellum. Sodium channels can be fever sensitive. This family demonstrates phenotypic variability of FGF14 deletions (SCA 27), fever sensitivity of ataxia and the added value of SNP-array analysis in making a diagnosis. PMID:24252256

  16. A comparison of the V/STOL handling qualities of the VAK-191B with the requirements of AGARD report 577 and MIL-F-83300

    NASA Technical Reports Server (NTRS)

    Anderson, S. B.

    1979-01-01

    The handling qualities of the VAK-191B VTOL aircraft are compared with current V/STOL handling qualities requirements. The aircraft handling qualities were superior to other V/STOL fighter aircraft. Several deficiencies which would seriously affect shipboard V/STOL operation includes: (1) poor hovering precision; (2) inadequate mechanical control characteristics; (3) nonlinear pitch and roll response; (4) an uncommanded movement of the height control lever; (5) low pitch control sensitivity; (6) excessive dihedral effect; and (7) inadequate overall thrust response. The attitude command control system resulted on reduced pilot workload during hover and low speed flight.

  17. Raptors and aircraft

    USGS Publications Warehouse

    Smith, D.G.; Ellis, D.H.; Johnson, T.H.

    1988-01-01

    Less than 5% of all bird strikes of aircraft are by raptor species, but damage to airframe structure or jet engine dysfunction are likely consequences. Beneficial aircraft-raptor interactions include the use of raptor species to frighten unwanted birds from airport areas and the use of aircraft to census raptor species. Many interactions, however, modify the raptor?s immediate behavior and some may decrease reproduction of sensitive species. Raptors may respond to aircraft stimuli by exhibiting alarm, increased heart rate, flushing or fleeing and occasionally by directly attacking intruding aircraft. To date, most studies reveal that raptor responses to aircraft are brief and do not limit reproduction; however, additional study is needed.

  18. Impaired vestibulo-ocular reflex (VOR) in spinocerebellar ataxia type 3 (SCA3): bedside and search coil evaluation.

    PubMed

    Gordon, Carlos R; Zivotofsky, Ari Z; Caspi, Avi

    2014-01-01

    Vestibulo-Ocular Reflex (VOR) abnormalities in cerebellar ataxias are a matter of renewed interest. We have previously reported vestibular areflexia in a group of Yemenite-Jews with Spinocerebellar Ataxia Type 3 (SCA3) who had clear bilateral pathological horizontal Head Impulse Test (HIT). The objective of this study was to evaluate the VOR of ten SCA3 patients who have variable bedside HIT responses by recording their eye movements using magnetic search coils and to correlate these results with their clinical and genetic data. Eight out of the ten patients have abnormal horizontal HIT detected by both clinical bedside examination and laboratory tests. Results of bedside HIT testing were significantly correlated with the VOR gain recorded using magnetic search coils. No significant correlations were found between VOR gain and other clinical or genetic data. Our study confirms the presence of defective VOR in SCA3 patients and corroborates the useful of the HIT as a reliable bedside test for diagnosis of VOR deficits. PMID:25564077

  19. Identification of genes encoding arabinosyltransferases (SCA) mediating developmental modifications of lipophosphoglycan required for sand fly transmission of leishmania major.

    PubMed

    Dobson, Deborah E; Mengeling, Brenda J; Cilmi, Salvatore; Hickerson, Suzanne; Turco, Salvatore J; Beverley, Stephen M

    2003-08-01

    At key steps in the infectious cycle pathogens must adhere to target cells, but at other times detachment is required for transmission. During sand fly infections by the protozoan parasite Leishmania major, binding of replicating promastigotes is mediated by galactosyl side chain (scGal) modifications of phosphoglycan repeats of the major surface adhesin, lipophosphoglycan (LPG). Release is mediated by arabinosyl (Ara) capping of LPG scbetaGal residues upon differentiation to the infective metacyclic stage. We used intraspecific polymorphisms of LPG structure to develop a genetic strategy leading to the identification of two genes (SCA1/2) mediating scAra capping. These LPG side chain beta1,2-arabinosyltransferases (scbetaAraTs) exhibit canonical glycosyltransferase motifs, and their overexpression leads to elevated microsomal scbetaAraT activity. Although the level of scAra caps is maximal in metacyclic parasites, scbetaAraT activity is maximal in log phase cells. Because quantitative immunolocalization studies suggest this is not mediated by sequestration of SCA scbetaAraTs away from the Golgi apparatus during log phase, regulation of activated Ara precursors may control LPG arabinosylation in vivo. The SCA genes define a new family of eukaryotic betaAraTs and represent novel developmentally regulated LPG-modifying activities identified in Leishmania. PMID:12750366

  20. Changes in Purkinje cell firing and gene expression precede behavioral pathology in a mouse model of SCA2.

    PubMed

    Hansen, Stephen T; Meera, Pratap; Otis, Thomas S; Pulst, Stefan M

    2013-01-15

    Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominantly inherited disorder, which is caused by a pathological expansion of a polyglutamine (polyQ) tract in the coding region of the ATXN2 gene. Like other ataxias, SCA2 most overtly affects Purkinje cells (PCs) in the cerebellum. Using a transgenic mouse model expressing a full-length ATXN2(Q127)-complementary DNA under control of the Pcp2 promoter (a PC-specific promoter), we examined the time course of behavioral, morphologic, biochemical and physiological changes with particular attention to PC firing in the cerebellar slice. Although motor performance began to deteriorate at 8 weeks of age, reductions in PC number were not seen until after 12 weeks. Decreases in the PC firing frequency first showed at 6 weeks and paralleled deterioration of motor performance with progression of disease. Transcription changes in several PC-specific genes such as Calb1 and Pcp2 mirrored the time course of changes in PC physiology with calbindin-28 K changes showing the first small, but significant decreases at 4 weeks. These results emphasize that in this model of SCA2, physiological and behavioral phenotypes precede morphological changes by several weeks and provide a rationale for future studies examining the effects of restoration of firing frequency on motor function and prevention of future loss of PCs. PMID:23087021

  1. Changes in Purkinje cell firing and gene expression precede behavioral pathology in a mouse model of SCA2

    PubMed Central

    Hansen, Stephen T.; Meera, Pratap; Otis, Thomas S.; Pulst, Stefan M.

    2013-01-01

    Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominantly inherited disorder, which is caused by a pathological expansion of a polyglutamine (polyQ) tract in the coding region of the ATXN2 gene. Like other ataxias, SCA2 most overtly affects Purkinje cells (PCs) in the cerebellum. Using a transgenic mouse model expressing a full-length ATXN2Q127-complementary DNA under control of the Pcp2 promoter (a PC-specific promoter), we examined the time course of behavioral, morphologic, biochemical and physiological changes with particular attention to PC firing in the cerebellar slice. Although motor performance began to deteriorate at 8 weeks of age, reductions in PC number were not seen until after 12 weeks. Decreases in the PC firing frequency first showed at 6 weeks and paralleled deterioration of motor performance with progression of disease. Transcription changes in several PC-specific genes such as Calb1 and Pcp2 mirrored the time course of changes in PC physiology with calbindin-28 K changes showing the first small, but significant decreases at 4 weeks. These results emphasize that in this model of SCA2, physiological and behavioral phenotypes precede morphological changes by several weeks and provide a rationale for future studies examining the effects of restoration of firing frequency on motor function and prevention of future loss of PCs. PMID:23087021

  2. 49 CFR 1560.109 - Aircraft Operator Implementation Plan.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... operator's security program as described in 49 CFR part 1544, subpart B, or 49 CFR part 1546, subpart B, as...) and must be handled and protected in accordance with 49 CFR part 1520. ... 49 Transportation 9 2012-10-01 2012-10-01 false Aircraft Operator Implementation Plan....

  3. 49 CFR 1560.109 - Aircraft Operator Implementation Plan.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... operator's security program as described in 49 CFR part 1544, subpart B, or 49 CFR part 1546, subpart B, as...) and must be handled and protected in accordance with 49 CFR part 1520. ... 49 Transportation 9 2013-10-01 2013-10-01 false Aircraft Operator Implementation Plan....

  4. 49 CFR 1560.109 - Aircraft Operator Implementation Plan.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... operator's security program as described in 49 CFR part 1544, subpart B, or 49 CFR part 1546, subpart B, as...) and must be handled and protected in accordance with 49 CFR part 1520. ... 49 Transportation 9 2014-10-01 2014-10-01 false Aircraft Operator Implementation Plan....

  5. 49 CFR 1560.109 - Aircraft Operator Implementation Plan.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... operator's security program as described in 49 CFR part 1544, subpart B, or 49 CFR part 1546, subpart B, as...) and must be handled and protected in accordance with 49 CFR part 1520. ... 49 Transportation 9 2010-10-01 2010-10-01 false Aircraft Operator Implementation Plan....

  6. Lightning effects on aircraft

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Direct and indirect effects of lightning on aircraft were examined in relation to aircraft design. Specific trends in design leading to more frequent lightning strikes were individually investigated. These trends included the increasing use of miniaturized, solid state components in aircraft electronics and electric power systems. A second trend studied was the increasing use of reinforced plastics and other nonconducting materials in place of aluminum skins, a practice that reduces the electromagnetic shielding furnished by a conductive skin.

  7. Bulk material handling system

    DOEpatents

    Kleysteuber, William K.; Mayercheck, William D.

    1979-01-01

    This disclosure relates to a bulk material handling system particularly adapted for underground mining and includes a monorail supported overhead and carrying a plurality of conveyors each having input and output end portions with the output end portion of a first of the conveyors positioned above an input end portion of a second of the conveyors, a device for imparting motion to the conveyors to move the material from the input end portions toward the output end portions thereof, a device for supporting at least one of the input and output end portions of the first and second conveyors from the monorail, and the supporting device including a plurality of trolleys rollingly supported by the monorail whereby the conveyors can be readily moved therealong.

  8. Handling hunger strikers.

    PubMed

    1992-04-01

    Hunger strikes are being used increasingly and not only by those with a political point to make. Whereas in the past, hunger strikes in the United Kingdom seemed mainly to be started by terrorist prisoners for political purposes, the most recent was begun by a Tamil convicted of murder, to protest his innocence. In the later stages of his strike, before calling it off, he was looked after at the Hammersmith Hospital. So it is not only prison doctors who need to know how to handle a hunger strike. The following guidelines, adopted by the 43rd World Medical Assembly in Malta in November 1991, are therefore a timely reminder of the doctor's duties during a hunger strike. PMID:16144144

  9. Aircraft fire safety research

    NASA Technical Reports Server (NTRS)

    Botteri, Benito P.

    1987-01-01

    During the past 15 years, very significant progress has been made toward enhancing aircraft fire safety in both normal and hostile (combat) operational environments. Most of the major aspects of the aircraft fire safety problem are touched upon here. The technology of aircraft fire protection, although not directly applicable in all cases to spacecraft fire scenarios, nevertheless does provide a solid foundation to build upon. This is particularly true of the extensive research and testing pertaining to aircraft interior fire safety and to onboard inert gas generation systems, both of which are still active areas of investigation.

  10. Hypersonic aircraft design

    NASA Technical Reports Server (NTRS)

    Alkamhawi, Hani; Greiner, Tom; Fuerst, Gerry; Luich, Shawn; Stonebraker, Bob; Wray, Todd

    1990-01-01

    A hypersonic aircraft is designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and it was decided that the aircraft would use one full scale turbofan-ramjet. Two solid rocket boosters were added to save fuel and help the aircraft pass through the transonic region. After considering aerodynamics, aircraft design, stability and control, cooling systems, mission profile, and landing systems, a conventional aircraft configuration was chosen over that of a waverider. The conventional design was chosen due to its landing characteristics and the relative expense compared to the waverider. Fuel requirements and the integration of the engine systems and their inlets are also taken into consideration in the final design. A hypersonic aircraft was designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and a full scale turbofan-ramjet was chosen. Two solid rocket boosters were added to save fuel and help the aircraft pass through the transonic reqion. After the aerodynamics, aircraft design, stability and control, cooling systems, mission profile, landing systems, and their physical interactions were considered, a conventional aircraft configuration was chosen over that of a waverider. The conventional design was chosen due to its landing characteristics and the relative expense compared to the waverider. Fuel requirements and the integration of the engine systems and their inlets were also considered in the designing process.

  11. Electrical conductivity structure of the north-western Fennoscandia (MaSca project)

    NASA Astrophysics Data System (ADS)

    Cherevatova, M.; Smirnov, M.; Korja, T. J.

    2013-12-01

    The Magnetotellurics in the Scandia (MaSca) project is aimed on the investigation of the crust, upper mantle and lithospheric structure of the north-western Fennoscandian Shield. The measurements are located in the area composed of the Precambrian rocks of ancient Baltica (in Sweden and Finland) and Silurian to Devonian rocks of Caledonian orogeny and post-orogenic extension (in Norway). The array covers an area of 500x400 square kilometers and stretches from Tromsø and Bodø (Norway) in the west to Kiruna and Skellefteå (Sweden) in the east. The project started in the summer 2011 and data collection continued till summer 2013, resulting all together in 70 synchronous long period (LMT) and 236 broad-band (BMT) sites. All LMT sites were occupied for about two months, while most of the BMT sites were measured during one day. The average distance between LMT sites is 30 km, and 10 km between BMT, however there are gaps of 50-80 km in the region of the Scandinavian Mountains. All the transfer functions were estimated using multi-remote reference technique as well as novel multivariate analysis technique, thus providing stable transfer function in the period range from 0.001 - 40000 s. Here we present the results of 2-D inversions along seven parallel profiles with an average distance of 60 km between profile lines. The strike determination from phase tensor and Q-function analyses showed a dominant direction of the regional structure being 40 degrees. However, the dimensionality analyses highlights 3-D effects in the data and presence of galvanic effects. Therefore, we inverted the determinant of the impedance tensor which is proved to be superior in such circumstances. The inverse solutions reveal extensive areas of resistive Precambrian lithosphere in south proper. Thick Cambro-Silurian successions occur in Nordland and Tromsø and presented as conductive upper crust layers in the west most likely composed of alum shales. A vast area of high conductivity in the

  12. A dominant spinocerebellar ataxia gene (SCA5) in a family descendent from the paternal grandparents of President Lincoln maps to chromosome 11

    SciTech Connect

    Ranum, L.P.W.; Lundgren, J.K.; Schut, L.J.

    1994-09-01

    Four different genes that cause spinocerebellar ataxia (SCA1, SCA2, Machado Joseph`s Disease (MJD)/SCA3 and SCA4) have been mapped to chromosomes 6p, 12q, 14q, and 16q, respectively. We have examined and collected 170 individuals (56 affected) from a previously unreported 10 generation kindred (the Lincoln Family) with a dominant ataxia that is clinically and genetically distinct from those previously mapped. The family has two major branches from Indiana and Kentucky. Of historical interest is that both branches descend from the paternal grandparents of President Abraham Lincoln. While the ataxia in this kindred is disabling, the most striking clinical distinction from SCA1, SCA2 and MJD/SCA3 is that it is generally not life threatening. This clinical difference is explained by the absence of bulbar paralysis and lower motor neuron degeneration that causes respiratory muscle weakness. We have mapped the gene, SCA5, using microsatellite markers spaced at 20-40 cM intervals throughout the genome. After 75 markers, the first to demonstrate a lod score greater than 3.0 was D11S871 (Zmax=5.05). Four additional markers from the centromeric region of chromosome 11 also gave lod scores greater than 3. The highest lod scores were 12.3 for both D11S905 ({theta}=0.056) and D11S913 ({theta}=0.030). Multipoint linkage and haplotype analyses indicate the most likely location for SCA5 is within the 7 cM interval between GATA2A01 and D11S913. A statistical analysis of the age of onset of parent-offspring pairs within the family supports (p<0.0002) the presence of anticipation. Several dramatic examples of anticipation have been observed in which grandmothers have onsets 10-20 years later in life than their daughters who have onsets 10-20 years later than their children. Interestingly, all four of the juvenile onset cases are maternally inherited, suggesting a maternal bias in anticipation for SCA5 rather than a paternal bias as seen with SCA1.

  13. Passive Thermal Design Approach for the Space Communications and Navigation (SCaN) Testbed Experiment on the International Space Station (ISS)

    NASA Technical Reports Server (NTRS)

    Siamidis, John; Yuko, Jim

    2014-01-01

    The Space Communications and Navigation (SCaN) Program Office at NASA Headquarters oversees all of NASAs space communications activities. SCaN manages and directs the ground-based facilities and services provided by the Deep Space Network (DSN), Near Earth Network (NEN), and the Space Network (SN). Through the SCaN Program Office, NASA GRC developed a Software Defined Radio (SDR) testbed experiment (SCaN testbed experiment) for use on the International Space Station (ISS). It is comprised of three different SDR radios, the Jet Propulsion Laboratory (JPL) radio, Harris Corporation radio, and the General Dynamics Corporation radio. The SCaN testbed experiment provides an on-orbit, adaptable, SDR Space Telecommunications Radio System (STRS) - based facility to conduct a suite of experiments to advance the Software Defined Radio, Space Telecommunications Radio Systems (STRS) standards, reduce risk (Technology Readiness Level (TRL) advancement) for candidate Constellation future space flight hardware software, and demonstrate space communication links critical to future NASA exploration missions. The SCaN testbed project provides NASA, industry, other Government agencies, and academic partners the opportunity to develop and field communications, navigation, and networking technologies in the laboratory and space environment based on reconfigurable, software defined radio platforms and the STRS Architecture.The SCaN testbed is resident on the P3 Express Logistics Carrier (ELC) on the exterior truss of the International Space Station (ISS). The SCaN testbed payload launched on the Japanese Aerospace Exploration Agency (JAXA) H-II Transfer Vehicle (HTV) and was installed on the ISS P3 ELC located on the inboard RAM P3 site. The daily operations and testing are managed out of NASA GRC in the Telescience Support Center (TSC).

  14. SCA7 cerebellar disease requires the coordinated action of mutant ataxin-7 in neurons and glia, and displays non-cell autonomous Bergmann glia degeneration

    PubMed Central

    Furrer, Stephanie A.; Mohanachandran, Mathini S.; Waldherr, Sarah M.; Chang, Christopher; Damian, Vincent A.; Sopher, Bryce L.; Garden, Gwenn A.; La Spada, Albert R.

    2011-01-01

    Spinocerebellar ataxia type 7 (SCA7) is a dominantly inherited disorder characterized by cerebellum and brainstem neurodegeneration. SCA7 is caused by a CAG/polyglutamine (polyQ) repeat expansion in the ataxin-7 gene. We previously reported that directed expression of polyQ-ataxin-7 in Bergmann glia (BG) in transgenic mice leads to ataxia and non-cell autonomous Purkinje cell (PC) degeneration. To further define the cellular basis of SCA7, we derived a conditional inactivation mouse model by inserting a loxP-flanked ataxin-7 cDNA with 92 repeats into the translational start site of the murine prion protein (PrP) gene in a bacterial artificial chromosome (BAC). The PrP-floxed-SCA7-92Q BAC mice developed neurological disease, and exhibited cerebellar degeneration and BG process loss. To inactivate polyQ-ataxin-7 expression in specific cerebellar cell types, we crossed PrP-floxed-SCA7-92Q BAC mice with Gfa2-Cre transgenic mice (to direct Cre to BG) or Pcp2-Cre transgenic mice (which yields Cre in PCs and inferior olive). Excision of ataxin-7 from BG partially rescued the behavioral phenotype, but did not prevent BG process loss or molecular layer thinning, while excision of ataxin-7 from PCs and inferior olive provided significantly greater rescue and prevented both pathological changes, revealing a non-cell autonomous basis for BG pathology. When we prevented expression of mutant ataxin-7 in BG, PCs, and inferior olive by deriving Gfa2-Cre;Pcp2-Cre;PrP-floxed-SCA7-92Q BAC triple transgenic mice, we noted a dramatic improvement in SCA7 disease phenotypes. These findings indicate that SCA7 disease pathogenesis involves a convergence of alterations in a variety of different cell types to fully recapitulate the cerebellar degeneration. PMID:22072678

  15. Human Factors In Aircraft Automation

    NASA Technical Reports Server (NTRS)

    Billings, Charles

    1995-01-01

    Report presents survey of state of art in human factors in automation of aircraft operation. Presents examination of aircraft automation and effects on flight crews in relation to human error and aircraft accidents.

  16. Unvented Drum Handling Plan

    SciTech Connect

    MCDONALD, K.M.

    2000-08-01

    This drum-handling plan proposes a method to deal with unvented transuranic drums encountered during retrieval of drums. Finding unvented drums during retrieval activities was expected, as identified in the Transuranic (TRU) Phase I Retrieval Plan (HNF-4781). However, significant numbers of unvented drums were not expected until excavation of buried drums began. This plan represents accelerated planning for management of unvented drums. A plan is proposed that manages unvented drums differently based on three categories. The first category of drums is any that visually appear to be pressurized. These will be vented immediately, using either the Hanford Fire Department Hazardous Materials (Haz. Mat.) team, if such are encountered before the facilities' capabilities are established, or using internal capabilities, once established. To date, no drums have been retrieved that showed signs of pressurization. The second category consists of drums that contain a minimal amount of Pu isotopes. This minimal amount is typically less than 1 gram of Pu, but may be waste-stream dependent. Drums in this category are assayed to determine if they are low-level waste (LLW). LLW drums are typically disposed of without venting. Any unvented drums that assay as TRU will be staged for a future venting campaign, using appropriate safety precautions in their handling. The third category of drums is those for which records show larger amounts of Pu isotopes (typically greater than or equal to 1 gram of Pu). These are assumed to be TRU and are not assayed at this point, but are staged for a future venting campaign. Any of these drums that do not have a visible venting device will be staged awaiting venting, and will be managed under appropriate controls, including covering the drums to protect from direct solar exposure, minimizing of container movement, and placement of a barrier to restrict vehicle access. There are a number of equipment options available to perform the venting. The

  17. General Aviation Aircraft Reliability Study

    NASA Technical Reports Server (NTRS)

    Pettit, Duane; Turnbull, Andrew; Roelant, Henk A. (Technical Monitor)

    2001-01-01

    This reliability study was performed in order to provide the aviation community with an estimate of Complex General Aviation (GA) Aircraft System reliability. To successfully improve the safety and reliability for the next generation of GA aircraft, a study of current GA aircraft attributes was prudent. This was accomplished by benchmarking the reliability of operational Complex GA Aircraft Systems. Specifically, Complex GA Aircraft System reliability was estimated using data obtained from the logbooks of a random sample of the Complex GA Aircraft population.

  18. Cable Tensiometer for Aircraft

    NASA Technical Reports Server (NTRS)

    Nunnelee, Mark (Inventor)

    2008-01-01

    The invention is a cable tensiometer that can be used on aircraft for real-time, in-flight cable tension measurements. The invention can be used on any aircraft cables with high precision. The invention is extremely light-weight, hangs on the cable being tested and uses a dual bending beam design with a high mill-volt output to determine tension.

  19. Civil aircraft accident investigation.

    PubMed

    Haines, Daniel

    2013-01-01

    This talk reviews some historic aircraft accidents and some more recent. It reflects on the division of accident causes, considering mechanical failures and aircrew failures, and on aircrew training. Investigation results may lead to improved aircraft design, and to appropriate crew training. PMID:24057309

  20. IC handling robot

    SciTech Connect

    Law, D.O.

    1986-09-01

    Allied Corporation, Bendix Kansas City Division uses many integrated circuits (ICs) which are 100% tested by receiving inspection prior to installation into the next assemblies. Testing includes functional testing followed by a burn-in cycle then additional functional testing. Before an IC can be functionally tested, it must be inserted into a custom plastic carrier which is placed into a metal magazine that fits the functional tester. The ICs are removed from both tester magazines and carriers prior to being placed into connectors mounted on a printed wiring board for burn-in. Then they are removed from the burn-in board and re-inserted into carriers and magazines for additional functional testing. Each device is handled manually a minimum of 12 times before it is accepted. This project established a robotic workcell which automatically prepares a dual in-line packaged (DIP) integrated circuit for several types of inspection operations performed by Receiving Inspection. Specific activities required to accomplish this goal included definition of the work cell, preparation of the robot and other equipment specifications, installation planning, establishment of programming routines and logic, design of operator safeguards, and development of the work cell concept into an operational unit capable of supporting production.

  1. REMOTE HANDLING ARRANGEMENTS

    DOEpatents

    Ginns, D.W.

    1958-04-01

    A means for handling remotely a sample pellet to be irradiated in a nuclear reactor is proposed. It is comprised essentially of an inlet tube extending through the outer shield of the reactor and being inclined so that its outer end is at a higher elevation than its inner end, an outlet tube extending through the outer shield being inclined so that its inner end is at a higher elevation than its outer end, the inner ends of these two tubes being interconnected, and a straight tube extending through the outer shield and into the reactor core between the inlet and outlet tubes and passing through the juncture of said inner ends. A rod-like member is rotatably and slidely operated within the central straight tube and has a receptacle on its inner end for receiving a sample pellet from the inlet tube. The rod member is operated to pick up a sample pellet from the inlet tube, carry the sample pellet into the irradiating position within the core, and return to the receiving position where it is rotated to dump the irradiated pellet into the outlet tube by which it is conveyed by gravity to the outside of the reactor. Stop members are provided in the inlet tube, and electrical operating devices are provided to control the sequence of the operation automatically.

  2. Aircraft operations management manual

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The NASA aircraft operations program is a multifaceted, highly diverse entity that directly supports the agency mission in aeronautical research and development, space science and applications, space flight, astronaut readiness training, and related activities through research and development, program support, and mission management aircraft operations flights. Users of the program are interagency, inter-government, international, and the business community. This manual provides guidelines to establish policy for the management of NASA aircraft resources, aircraft operations, and related matters. This policy is an integral part of and must be followed when establishing field installation policy and procedures covering the management of NASA aircraft operations. Each operating location will develop appropriate local procedures that conform with the requirements of this handbook. This manual should be used in conjunction with other governing instructions, handbooks, and manuals.

  3. Why aircraft disinsection?

    PubMed Central

    Gratz, N. G.; Steffen, R.; Cocksedge, W.

    2000-01-01

    A serious problem is posed by the inadvertent transport of live mosquitoes aboard aircraft arriving from tropical countries where vector-borne diseases are endemic. Surveys at international airports have found many instances of live insects, particularly mosquitoes, aboard aircraft arriving from countries where malaria and arboviruses are endemic. In some instances mosquito species have been established in countries in which they have not previously been reported. A serious consequence of the transport of infected mosquitoes aboard aircraft has been the numerous cases of "airport malaria" reported from Europe, North America and elsewhere. There is an important on-going need for the disinsection of aircraft coming from airports in tropical disease endemic areas into nonendemic areas. The methods and materials available for use in aircraft disinsection and the WHO recommendations for their use are described. PMID:10994283

  4. A Flight Investigation of the STOL Characteristics of an Augmented Jet Flap STOL Research Aircraft

    NASA Technical Reports Server (NTRS)

    Quigley, H. C.; Innis, R. C.; Grossmith, S.

    1974-01-01

    The flight test program objectives are: (1) To determine the in-flight aerodynamic, performance, and handling qualities of a jet STOL aircraft incorporating the augmented jet flap concept; (2) to compare the results obtained in flight with characteristics predicted from wind tunnel and simulator test results; (3) to contribute to the development of criteria for design and operation of jet STOL transport aircraft; and (4) to provide a jet STOL transport aircraft for STOL systems research and development. Results obtained during the first 8 months of proof-of-concept flight testing of the aircraft in STOL configurations are reported. Included are a brief description of the aircraft, fan-jet engines, and systems; a discussion of the aerodynamic, stability and control, and STOL performance; and pilot opinion of the handling qualities and operational characteristics.

  5. Sampling scheme for pyrethroids on multiple surfaces on commercial aircrafts.

    PubMed

    Mohan, Krishnan R; Weisel, Clifford P

    2010-06-01

    A wipe sampler for the collection of permethrin from soft and hard surfaces has been developed for use in aircraft. "Disinsection" or application of pesticides, predominantly pyrethrods, inside commercial aircraft is routinely required by some countries and is done on an as-needed basis by airlines resulting in potential pesticide dermal and inhalation exposures to the crew and passengers. A wipe method using filter paper and water was evaluated for both soft and hard aircraft surfaces. Permethrin was analyzed by GC/MS after its ultrasonication extraction from the sampling medium into hexane and volume reduction. Recoveries, based on spraying known levels of permethrin, were 80-100% from table trays, seat handles and rugs; and 40-50% from seat cushions. The wipe sampler is easy to use, requires minimum training, is compatible with the regulations on what can be brought through security for use on commercial aircraft, and readily adaptable for use in residential and other settings. PMID:19756041

  6. The ScaLIng Macroweather Model (SLIMM) and monthly and inter annual regional forecasting.

    NASA Astrophysics Data System (ADS)

    Lovejoy, S.; Del Rio Amador, L.; Sloman, L.

    2015-12-01

    By exploiting the sensitive dependence on initial conditions, GCM's can generate a statistical ensemble of future states in which the high frequency "weather" is treated as a driving noise. Following Hasselman, 1976, this has lead to stochastic models that directly generate the noise, and model the low frequencies using systems of integer ordered linear ordinary differential equations, the most well known are the linear inverse models (LIM). These have been presented as a benchmark for decadal surface temperature forecast. Using the LIM, hindcast skills comparable to and sometimes even better than the skill of (coupled) Global Circulation Models (GCM's) from phase 5 of the Coupled Model Intercomparison Project (CMIP5). Nevertheless, the short range exponential temporal decorrelations implicit in the LIM models are unrealistic (the true decorrelations are closer to long range power laws), and - as a consequence - the useful limit to the forecast horizon is roughly one year: it enormously underestimates the memory of the system. In presentation, we make a scaling analogue of the LIM: ScaLIng Macroweather Model (SLIMM) that exploits the power law (scaling) behavior in time of the temperature field and consequently, make use of the long history dependence of the data to improve the skill. The results predicted analytically by the model have been tested by performing actual hindcasts in different 5º x 5º regions on the planet using the Twentieth Century Reanalysis as a reference datasets. As a first step, we removed the anthropogenic component of each time series based on its sensitivity to equivalent CO2 concentration for the last 130 years, the residues are our estimates of the natural variability that SLIMM predicts. This residues were treated as fractional Gaussian noise processes with scaling exponent H between -0.5 and 0. The value of H for each grid-point can be obtained directly from the data. We report maps of theoretical skill predicted by the model and we

  7. Fluid handling equipment: A compilation

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Devices and techniques used in fluid-handling and vacuum systems are described. Section 1 presents several articles on fluid lines and tubing. Section 2 describes a number of components such as valves, filters, and regulators. The last section contains descriptions of a number of innovative fluid-handling systems.

  8. The Small Aircraft Transportation System (SATS), Higher Volume Operations (HVO) Off-Nominal Operations

    NASA Technical Reports Server (NTRS)

    Baxley, B.; Williams, D.; Consiglio, M.; Conway, S.; Adams, C.; Abbott, T.

    2005-01-01

    The ability to conduct concurrent, multiple aircraft operations in poor weather, at virtually any airport, offers an important opportunity for a significant increase in the rate of flight operations, a major improvement in passenger convenience, and the potential to foster growth of charter operations at small airports. The Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept is designed to increase traffic flow at any of the 3400 nonradar, non-towered airports in the United States where operations are currently restricted to one-in/one-out procedural separation during Instrument Meteorological Conditions (IMC). The concept's key feature is pilots maintain their own separation from other aircraft using procedures, aircraft flight data sent via air-to-air datalink, cockpit displays, and on-board software. This is done within the Self-Controlled Area (SCA), an area of flight operations established during poor visibility or low ceilings around an airport without Air Traffic Control (ATC) services. The research described in this paper expands the HVO concept to include most off-nominal situations that could be expected to occur in a future SATS environment. The situations were categorized into routine off-nominal operations, procedural deviations, equipment malfunctions, and aircraft emergencies. The combination of normal and off-nominal HVO procedures provides evidence for an operational concept that is safe, requires little ground infrastructure, and enables concurrent flight operations in poor weather.

  9. Predicting visibility of aircraft.

    PubMed

    Watson, Andrew; Ramirez, Cesar V; Salud, Ellen

    2009-01-01

    Visual detection of aircraft by human observers is an important element of aviation safety. To assess and ensure safety, it would be useful to be able to be able to predict the visibility, to a human observer, of an aircraft of specified size, shape, distance, and coloration. Examples include assuring safe separation among aircraft and between aircraft and unmanned vehicles, design of airport control towers, and efforts to enhance or suppress the visibility of military and rescue vehicles. We have recently developed a simple metric of pattern visibility, the Spatial Standard Observer (SSO). In this report we examine whether the SSO can predict visibility of simulated aircraft images. We constructed a set of aircraft images from three-dimensional computer graphic models, and measured the luminance contrast threshold for each image from three human observers. The data were well predicted by the SSO. Finally, we show how to use the SSO to predict visibility range for aircraft of arbitrary size, shape, distance, and coloration. PMID:19462007

  10. Predicting Visibility of Aircraft

    PubMed Central

    Watson, Andrew; Ramirez, Cesar V.; Salud, Ellen

    2009-01-01

    Visual detection of aircraft by human observers is an important element of aviation safety. To assess and ensure safety, it would be useful to be able to be able to predict the visibility, to a human observer, of an aircraft of specified size, shape, distance, and coloration. Examples include assuring safe separation among aircraft and between aircraft and unmanned vehicles, design of airport control towers, and efforts to enhance or suppress the visibility of military and rescue vehicles. We have recently developed a simple metric of pattern visibility, the Spatial Standard Observer (SSO). In this report we examine whether the SSO can predict visibility of simulated aircraft images. We constructed a set of aircraft images from three-dimensional computer graphic models, and measured the luminance contrast threshold for each image from three human observers. The data were well predicted by the SSO. Finally, we show how to use the SSO to predict visibility range for aircraft of arbitrary size, shape, distance, and coloration. PMID:19462007

  11. Supplemental Control for Aircraft Riding Qualities

    NASA Technical Reports Server (NTRS)

    Williams, Rolanda S.; Ashokkumar, C. R.; Homaifar, Abdollah

    1997-01-01

    The concept of preview control has been applied and proven to be successful in the automotive vehicle. These same concepts are now applied to an aircraft under the assumption that exogenous inputs (wind gust, turbulence, etc. ) can be measured. A supplemental control law for surface deflection is designed to compensate for the loss in performance in the presence of atmospheric disturbances. Fuzzy logic control is employed to handle the nonlinear, time varying characteristics of the disturbance. A methodology to tune the outer loop control parameters is presented.

  12. Predicted electrothermal deicing of aircraft blades

    NASA Technical Reports Server (NTRS)

    Keith, T. G., Jr.; Masiulaniec, K. C.; Dewitt, K. J.; Chao, D. F.

    1984-01-01

    A finite difference method is presented for the transient two-dimensional simulation of an electrothermal de-icer pad of an aircraft wing or blade. The irregular geometry of the composite ice laden blade is handled by use of a body fitted coordinate transformation. By this approach the various blade layers are mapped into a set of stacked rectangular strips in which the numerical solution takes place. Several heat conduction examples are presented in order to demonstrate the accuracy of the numerical procedure. Ice melting time predictions are made and compared to earlier predictions where possible. Finally, a new graphical presentation of thermal results is shown.

  13. Advanced simulation noise model for modern fighter aircraft

    NASA Astrophysics Data System (ADS)

    Ikelheimer, Bruce

    2005-09-01

    NoiseMap currently represents the state of the art for military airfield noise analysis. While this model is sufficient for the current fleet of aircraft, it has limits in its capability to model the new generation of fighter aircraft like the JSF and the F-22. These aircraft's high-powered engines produce noise with significant nonlinear content. Combining this with their ability to vector the thrust means they have noise characteristics that are outside of the basic modeling assumptions of the currently available noise models. Wyle Laboratories, Penn State University, and University of Alabama are in the process of developing a new noise propagation model for the Strategic Environmental Research and Development Program. Source characterization will be through complete spheres (or hemispheres if there is not sufficient data) for each aircraft state (including thrust vector angles). Fixed and rotor wing aircraft will be included. Broadband, narrowband, and pure tone propagation will be included. The model will account for complex terrain and weather effects, as well as the effects of nonlinear propagation. It will be a complete model capable of handling a range of noise sources from small subsonic general aviation aircraft to the latest fighter aircraft like the JSF.

  14. Study of dynamics of X-14B VTOL aircraft

    NASA Technical Reports Server (NTRS)

    Loscutoff, W. V.; Mitchiner, J. L.; Roesener, R. A.; Seevers, J. A.

    1973-01-01

    Research was initiated to investigate certain facets of modern control theory and their integration with a digital computer to provide a tractable flight control system for a VTOL aircraft. Since the hover mode is the most demanding phase in the operation of a VTOL aircraft, the research efforts were concentrated in this mode of aircraft operation. Research work on three different aspects of the operation of the X-14B VTOL aircraft is discussed. A general theory for optimal, prespecified, closed-loop control is developed. The ultimate goal was optimal decoupling of the modes of the VTOL aircraft to simplify the pilot's task of handling the aircraft. Modern control theory is used to design deterministic state estimators which provide state variables not measured directly, but which are needed for state variable feedback control. The effect of atmospheric turbulence on the X-14B is investigated. A maximum magnitude gust envelope within which the aircraft could operate stably with the available control power is determined.

  15. Review of evolving trends in blended wing body aircraft design

    NASA Astrophysics Data System (ADS)

    Okonkwo, Paul; Smith, Howard

    2016-04-01

    The desire to produce environmentally friendly aircraft that is aerodynamically efficient and capable of conveying large number of passengers over long ranges at reduced direct operating cost led aircraft designers to develop the Blended Wing Body (BWB) aircraft concept. The BWB aircraft represents a paradigm shift in the design of aircraft. The design provides aerodynamics and environmental benefits and is suitable for the integration of advanced systems and concepts like laminar flow technology, jet flaps and distributed propulsion. However, despite these benefits, the BWB is yet to be developed for commercial air transport due to several challenges. This paper reviews emerging trends in BWB aircraft design highlighting design challenges that have hindered the development of a BWB passenger transport aircraft. The study finds that in order to harness the advantages and reduce the deficiencies of a tightly coupled configuration like the BWB, a multidisciplinary design synthesis optimisation should be conducted with good handling and ride quality as objective functions within acceptable direct operating cost and noise bounds.

  16. The Small Aircraft Transportation System (SATS), Higher Volume Operations (HVO) Concept and Research

    NASA Technical Reports Server (NTRS)

    Baxley, B.; Williams, D.; Consiglio, M.; Adams, C.; Abbott, T.

    2005-01-01

    The ability to conduct concurrent, multiple aircraft operations in poor weather at virtually any airport offers an important opportunity for a significant increase in the rate of flight operations, a major improvement in passenger convenience, and the potential to foster growth of operations at small airports. The Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept is designed to increase capacity at the 3400 non-radar, non-towered airports in the United States where operations are currently restricted to one-in/one-out procedural separation during low visibility or ceilings. The concept s key feature is that pilots maintain their own separation from other aircraft using air-to-air datalink and on-board software within the Self-Controlled Area (SCA), an area of flight operations established during poor visibility and low ceilings around an airport without Air Traffic Control (ATC) services. While pilots self-separate within the SCA, an Airport Management Module (AMM) located at the airport assigns arriving pilots their sequence based on aircraft performance, position, winds, missed approach requirements, and ATC intent. The HVO design uses distributed decision-making, safe procedures, attempts to minimize pilot and controller workload, and integrates with today's ATC environment. The HVO procedures have pilots make their own flight path decisions when flying in Instrument Metrological Conditions (IMC) while meeting these requirements. This paper summarizes the HVO concept and procedures, presents a summary of the research conducted and results, and outlines areas where future HVO research is required. More information about SATS HVO can be found at http://ntrs.nasa.gov.

  17. Validation of a Bayesian reconstruction approach to estimate snow water equivalent via assimilation of MODIS fractional SCA data

    NASA Astrophysics Data System (ADS)

    Girotto, M.; Margulis, S. A.; Durand, M. T.; Molotch, N. P.

    2010-12-01

    Seasonal snowmelt runoff represents one of the major components of water resources in many regions of the world. Lack of knowledge of its spatial and temporal characteristics limits our ability to monitor and predict this vital source of water. Process understanding stands to benefit from an accurate spatial and temporal characterization of the mountain snow water equivalent (SWE) spatial distribution and evolution. A probabilistic approach that takes into account sources of uncertainty from all input data streams (including remote sensing and models and their inputs) while estimating SWE is desired. This work applied a Bayesian reanalysis data assimilation system, similar to an Ensemble Kalman Smoother, capable of merging remotely sensed Snow Covered Area (SCA) data into prediction models, and at the same time account for the limitations of each. Preliminary analysis has identified and characterized the key factors responsible for SWE estimation accuracy, and developed models able to represent their uncertainties within the probabilistic data assimilation approach. The approach was implemented for the characterization of spatially and temporally continuous SWE over a test domain in the Sequoia National Park region of the Sierra Nevada. To assess the performance of the method, SWE spatial estimates are compared with estimates from intense field campaigns, and existing snow-pillow records. SCA estimates from both the standard fractional MODIS product and the advanced MODSCAG are investigated as they have been derived with different retrieval algorithms. The system is designed to use readily available forcing information from the North American Land Data Assimilation System (NLDAS). Prior estimates of SWE are obtained by forcing a land surface model with prior probability distributions of snowfall obtained from the NLDAS precipitation product. A reanalysis step conditions the prior estimates on SCA measurements. A series of preliminary analyses focus on identifying

  18. A strategic planning methodology for aircraft redesign

    NASA Astrophysics Data System (ADS)

    Romli, Fairuz Izzuddin

    Due to a progressive market shift to a customer-driven environment, the influence of engineering changes on the product's market success is becoming more prominent. This situation affects many long lead-time product industries including aircraft manufacturing. Derivative development has been the key strategy for many aircraft manufacturers to survive the competitive market and this trend is expected to continue in the future. Within this environment of design adaptation and variation, the main market advantages are often gained by the fastest aircraft manufacturers to develop and produce their range of market offerings without any costly mistakes. This realization creates an emphasis on the efficiency of the redesign process, particularly on the handling of engineering changes. However, most activities involved in the redesign process are supported either inefficiently or not at all by the current design methods and tools, primarily because they have been mostly developed to improve original product development. In view of this, the main goal of this research is to propose an aircraft redesign methodology that will act as a decision-making aid for aircraft designers in the change implementation planning of derivative developments. The proposed method, known as Strategic Planning of Engineering Changes (SPEC), combines the key elements of the product redesign planning and change management processes. Its application is aimed at reducing the redesign risks of derivative aircraft development, improving the detection of possible change effects propagation, increasing the efficiency of the change implementation planning and also reducing the costs and the time delays due to the redesign process. To address these challenges, four research areas have been identified: baseline assessment, change propagation prediction, change impact analysis and change implementation planning. Based on the established requirements for the redesign planning process, several methods and

  19. Loftin Collection - Boeing Aircraft

    NASA Technical Reports Server (NTRS)

    1933-01-01

    Either a F2B-1 or F3B-1, both aircraft were built by Boeing and both were powered by Pratt and Whitney Wasp engines. These fighters were intended for Navy shipboard use. Boeing F3B-1: While most Boeing F3B-1s served the U. S. Navy aircraft carriers the Lexington and the Saratoga, this example flew in NACA hands at the Langley Memorial Aeronautical Laboratory in the late 1920's. Also known as the Boeing Model 77, the aircraft was the next to last F3B-1 build in November 1928.

  20. OVRhyp, Scramjet Test Aircraft

    NASA Technical Reports Server (NTRS)

    Aslan, J.; Bisard, T.; Dallinga, S.; Draper, K.; Hufford, G.; Peters, W.; Rogers, J.

    1990-01-01

    A preliminary design for an unmanned hypersonic research vehicle to test scramjet engines is presented. The aircraft will be launched from a carrier aircraft at an altitude of 40,000 feet at Mach 0.8. The vehicle will then accelerate to Mach 6 at an altitude of 100,000 feet. At this stage the prototype scramjet will be employed to accelerate the vehicle to Mach 10 and maintain Mach 10 flight for 2 minutes. The aircraft will then decelerate and safely land.

  1. Some fighter aircraft trends

    NASA Technical Reports Server (NTRS)

    Spearman, L.

    1985-01-01

    Some basic trends in fighters are traced from the post World II era. Beginning with the first operational jet fighter, the P-80, the characteristics of subsequent fighter aircraft are examined for performance, mission capability, effectiveness, and cost. Characteristics presented include: power loading, wing loading, maximum speed, rate of climb, turn rate, weight and weight distribution, cost and cost distribution. The characteristics of some USSR aircraft are included for comparison. The trends indicate some of the rationale for certain fighter designs and some likely characteristics to be sought in future fighter aircraft designs.

  2. Tropospheric sampling with aircraft

    SciTech Connect

    Daum, P.H.; Springston, S.R.

    1991-03-01

    Aircraft constitute a unique environment which places stringent requirements on the instruments used to measure the concentrations of atmospheric trace gases and aerosols. Some of these requirements such as minimization of size, weight, and power consumption are general; others are specific to individual techniques. This review presents the basic principles and considerations governing the deployment of trace gas and aerosol instrumentation on an aircraft. An overview of common instruments illustrates these points and provides guidelines for designing and using instruments on aircraft-based measurement programs.

  3. Aircraft compass characteristics

    NASA Technical Reports Server (NTRS)

    Peterson, John B; Smith, Clyde W

    1937-01-01

    A description of the test methods used at the National Bureau of Standards for determining the characteristics of aircraft compasses is given. The methods described are particularly applicable to compasses in which mineral oil is used as the damping liquid. Data on the viscosity and density of certain mineral oils used in United States Navy aircraft compasses are presented. Characteristics of Navy aircraft compasses IV to IX and some other compasses are shown for the range of temperatures experienced in flight. Results of flight tests are presented. These results indicate that the characteristic most desired in a steering compass is a short period and, in a check compass, a low overswing.

  4. Microwave imaging of aircraft

    NASA Astrophysics Data System (ADS)

    Steinberg, Bernard D.

    1988-12-01

    Three methods of imaging aircraft from the ground with microwave radar with quality suitable for aircraft target recognition are described. The imaging methods are based on a self-calibration procedure called adaptive beamforming that compensates for the severe geometric distortion inherent in any imaging system that is large enough to achieve the high angular resolution necessary for two-dimensional target imaging. The signal processing algorithm is described and X-band (3-cm)-wavelength experiments demonstrate its success on commercial aircraft flying into Philadelphia International Airport.

  5. Aircraft electromagnetic compatibility

    NASA Technical Reports Server (NTRS)

    Clarke, Clifton A.; Larsen, William E.

    1987-01-01

    Illustrated are aircraft architecture, electromagnetic interference environments, electromagnetic compatibility protection techniques, program specifications, tasks, and verification and validation procedures. The environment of 400 Hz power, electrical transients, and radio frequency fields are portrayed and related to thresholds of avionics electronics. Five layers of protection for avionics are defined. Recognition is given to some present day electromagnetic compatibility weaknesses and issues which serve to reemphasize the importance of EMC verification of equipment and parts, and their ultimate EMC validation on the aircraft. Proven standards of grounding, bonding, shielding, wiring, and packaging are laid out to help provide a foundation for a comprehensive approach to successful future aircraft design and an understanding of cost effective EMC in an aircraft setting.

  6. Predicting Aircraft Noise Levels

    NASA Technical Reports Server (NTRS)

    Clark, B. J.

    1983-01-01

    Computer program developed for predicting aircraft noise levels either in flight or in ground tests. Noise sources include fan inlet and exhaust jet flap (for powered lift), core (combustor), turbine and airframe. Program written in FORTRAN IV.

  7. Aircraft parameter estimation

    NASA Technical Reports Server (NTRS)

    Iliff, Kenneth W.

    1987-01-01

    The aircraft parameter estimation problem is used to illustrate the utility of parameter estimation, which applies to many engineering and scientific fields. Maximum likelihood estimation has been used to extract stability and control derivatives from flight data for many years. This paper presents some of the basic concepts of aircraft parameter estimation and briefly surveys the literature in the field. The maximum likelihood estimator is discussed, and the basic concepts of minimization and estimation are examined for a simple simulated aircraft example. The cost functions that are to be minimized during estimation are defined and discussed. Graphic representations of the cost functions are given to illustrate the minimization process. Finally, the basic concepts are generalized, and estimation from flight data is discussed. Some of the major conclusions for the simulated example are also developed for the analysis of flight data from the F-14, highly maneuverable aircraft technology (HiMAT), and space shuttle vehicles.

  8. Aircraft Engine Emissions. [conference

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A conference on a aircraft engine emissions was held to present the results of recent and current work. Such diverse areas as components, controls, energy efficient engine designs, and noise and pollution reduction are discussed.

  9. Solar thermal aircraft

    DOEpatents

    Bennett, Charles L.

    2007-09-18

    A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

  10. Aircraft Safety Improvement

    NASA Technical Reports Server (NTRS)

    Kao, G.

    1985-01-01

    Fabrication and testing of honeycomb sandwich aircraft panels are discussed. Also described is the use of the following instruments: thermogravimetric analyzer, differential scanning calorimeter, limiting oxygen index, and infrared spectrometer.

  11. Aircraft electromagnetic compatibility

    NASA Astrophysics Data System (ADS)

    Clarke, Clifton A.; Larsen, William E.

    1987-06-01

    Illustrated are aircraft architecture, electromagnetic interference environments, electromagnetic compatibility protection techniques, program specifications, tasks, and verification and validation procedures. The environment of 400 Hz power, electrical transients, and radio frequency fields are portrayed and related to thresholds of avionics electronics. Five layers of protection for avionics are defined. Recognition is given to some present day electromagnetic compatibility weaknesses and issues which serve to reemphasize the importance of EMC verification of equipment and parts, and their ultimate EMC validation on the aircraft. Proven standards of grounding, bonding, shielding, wiring, and packaging are laid out to help provide a foundation for a comprehensive approach to successful future aircraft design and an understanding of cost effective EMC in an aircraft setting.

  12. Laminar Flow Aircraft Certification

    NASA Technical Reports Server (NTRS)

    Williams, Louis J. (Compiler)

    1986-01-01

    Various topics telative to laminar flow aircraft certification are discussed. Boundary layer stability, flaps for laminar flow airfoils, computational wing design studies, manufacturing requirements, windtunnel tests, and flow visualization are among the topics covered.

  13. The Aircraft Morphing Program

    NASA Technical Reports Server (NTRS)

    Wlezien, R. W.; Horner, G. C.; McGowan, A. R.; Padula, S. L.; Scott, M. A.; Silcox, R. J.; Simpson, J. O.

    1998-01-01

    In the last decade smart technologies have become enablers that cut across traditional boundaries in materials science and engineering. Here we define smart to mean embedded actuation, sensing, and control logic in a tightly coupled feedback loop. While multiple successes have been achieved in the laboratory, we have yet to see the general applicability of smart devices to real aircraft systems. The NASA Aircraft Morphing program is an attempt to couple research across a wide range of disciplines to integrate smart technologies into high payoff aircraft applications. The program bridges research in seven individual disciplines and combines the effort into activities in three primary program thrusts. System studies are used to assess the highest- payoff program objectives, and specific research activities are defined to address the technologies required for development of smart aircraft systems. In this paper we address the overall program goals and programmatic structure, and discuss the challenges associated with bringing the technologies to fruition.

  14. Advanced hypersonic aircraft design

    NASA Technical Reports Server (NTRS)

    Utzinger, Rob; Blank, Hans-Joachim; Cox, Craig; Harvey, Greg; Mckee, Mike; Molnar, Dave; Nagy, Greg; Petersen, Steve

    1992-01-01

    The objective of this design project is to develop the hypersonic reconnaissance aircraft to replace the SR-71 and to complement existing intelligence gathering devices. The initial design considerations were to create a manned vehicle which could complete its mission with at least two airborne refuelings. The aircraft must travel between Mach 4 and Mach 7 at an altitude of 80,000 feet for a maximum range of 12,000 nautical miles. The vehicle should have an air breathing propulsion system at cruise. With a crew of two, the aircraft should be able to take off and land on a 10,000 foot runway, and the yearly operational costs were not to exceed $300 million. Finally, the aircraft should exhibit stealth characteristics, including a minimized radar cross-section (RCS) and a reduced sonic boom. The technology used in this vehicle should allow for production between the years 1993 and 1995.

  15. Aircraft of the future

    NASA Technical Reports Server (NTRS)

    Yeger, S.

    1985-01-01

    Some basic problems connected with attempts to increase the size and capacity of transport aircraft are discussed. According to the square-cubic law, the increase in structural weight is proportional to the third power of the increase in the linear dimensions of the aircraft when geomettric similarity is maintained, while the surface area of the aircraft increases according to the second power. A consequence is that the fraction of useful weight will decrease as aircraft increase in size. However, in flying-wing designs in which the whole load on the wing is proportional to the distribution of lifting forces, the total bending moment on the wing will be sharply reduced, enabling lighter construction. Flying wings may have an ultimate capacity of 3000 passengers.

  16. Depreciation of aircraft

    NASA Technical Reports Server (NTRS)

    Warner, Edward P

    1922-01-01

    There is a widespread, and quite erroneous, impression to the effect that aircraft are essentially fragile and deteriorate with great rapidity when in service, so that the depreciation charges to be allowed on commercial or private operation are necessarily high.

  17. Alternative jet aircraft fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1979-01-01

    Potential changes in jet aircraft fuel specifications due to shifts in supply and quality of refinery feedstocks are discussed with emphasis on the effects these changes would have on the performance and durability of aircraft engines and fuel systems. Combustion characteristics, fuel thermal stability, and fuel pumpability at low temperature are among the factors considered. Combustor and fuel system technology needs for broad specification fuels are reviewed including prevention of fuel system fouling and fuel system technology for fuels with higher freezing points.

  18. ANALYSIS OF AIRCRAFT MOTIONS

    NASA Technical Reports Server (NTRS)

    Wingrove, R. C.

    1994-01-01

    This program was developed by Ames Research Center, in cooperation with the National Transportation Safety Board, as a technique for deriving time histories of an aircraft's motion from Air Traffic Control (ATC) radar records. This technique uses the radar range and azimuth data, along with the downlinked altitude data, to derive an expanded set of data which includes airspeed, lift, attitude angles (pitch, roll, and heading), etc. This technique should prove useful as a source of data in the investigation of commercial airline accidents and in the analysis of accidents involving aircraft which do not have onboard data recorders (e.g., military, short-haul, and general aviation). The technique used to determine the aircraft motions involves smoothing of raw radar data. These smoothed results, in combination with other available information (wind profiles and aircraft performance data), are used to derive the expanded set of data. This program uses a cubic least-square fit to smooth the raw data. This moving-arc procedure provides a smoothed time history of the aircraft position, the inertial velocities, and accelerations. Using known winds, these inertial data are transformed to aircraft stability axes to provide true airspeed, thrust-drag, lift, and roll angle. Further derivation, based on aircraft dependent performance data, can determine the aircraft angle of attack, pitch, and heading angle. Results of experimental tests indicate that values derived from ATC radar records using this technique agree favorably with airborne measurements. This program is written in FORTRAN IV to be executed in the batch mode, and has been implemented on a CDC 6000 series computer with a central memory requirement of 64k (octal) of 60 bit words.

  19. Remote handling devices in MLF

    NASA Astrophysics Data System (ADS)

    Kinoshita, Hidetaka; Teshigawara, Makoto; Ito, Manabu; Takagiwa, Katsunori; Meigo, Shinichiro; Maekawa, Fujio; Kaminaga, Masanori; Futakawa, Masatoshi

    2009-02-01

    The experimental facilities at J-PARC (Japan Proton Accelerator Research Complex) include the Materials and Life science Facility (MLF) with a JSNS (Japan Spallation Neutron Source). The main components of the JSNS need to be exchanged because of material damage due to proton and neutron irradiation. The irradiated components must be remotely maintained. Several kinds of areas, such as a hot-cell, are provided for remote handling operations. Several remote handling devices, such as a power manipulator (PM), master-slave manipulators (MSMs), a target exchange truck, a cutting device, a moderator exchange device, etc. have been installed. The commissioning tests for the remote handling devices are almost complete.

  20. HAND TRUCK FOR HANDLING EQUIPMENT

    DOEpatents

    King, D.W.

    1959-02-24

    A truck is described for the handling of large and relatively heavy pieces of equipment and particularly for the handling of ion source units for use in calutrons. The truck includes a chassis and a frame pivoted to the chassis so as to be operable to swing in the manner of a boom. The frame has spaced members so arranged that the device to be handled can be suspended between or passed between these spaced members and also rotated with respect to the frame when the device is secured to the spaced members.

  1. Information Handling is the Problem

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.

    2001-01-01

    This slide presentation reviews the concerns surrounding the automation of information handling. There are two types of decision support software that supports most Space Station Flight Controllers. one is very simple, and the other is very complex. A middle ground is sought. This is the reason for the Human Centered Autonomous and Assistant Systems Testbed (HCAAST) Project. The aim is to study flight controllers at work, and in the bigger picture, with particular attention to how they handle information and how coordination of multiple teams is performed. The focus of the project is on intelligent assistants to assist in handling information for the flight controllers.

  2. V/STOL tilt rotor aircraft study mathematical model for a real time simulation of a tilt rotor aircraft (Boeing Vertol Model 222), volume 8

    NASA Technical Reports Server (NTRS)

    Rosenstein, H.; Mcveigh, M. A.; Mollenkof, P. A.

    1973-01-01

    A mathematical model for a real time simulation of a tilt rotor aircraft was developed. The mathematical model is used for evaluating aircraft performance and handling qualities. The model is based on an eleven degree of freedom total force representation. The rotor is treated as a point source of forces and moments with appropriate response time lags and actuator dynamics. The aerodynamics of the wing, tail, rotors, landing gear, and fuselage are included.

  3. Primitive Sca-1 Positive Bone Marrow HSC in Mouse Model of Aplastic Anemia: A Comparative Study through Flowcytometric Analysis and Scanning Electron Microscopy

    PubMed Central

    Chatterjee, Sumanta; Basak, Pratima; Das, Prosun; Das, Madhurima; Pereira, Jacintha Archana; Dutta, Ranjan Kumar; Chaklader, Malay; Chaudhuri, Samaresh; Law, Sujata

    2010-01-01

    Self-renewing Hematopoietic Stem Cells (HSCs) are responsible for reconstitution of all blood cell lineages. Sca-1 is the “stem cell antigen” marker used to identify the primitive murine HSC population, the expression of which decreases upon differentiation to other mature cell types. Sca-1+ HSCs maintain the bone marrow stem cell pool throughout the life. Aplastic anemia is a disease considered to involve primary stem cell deficiency and is characterized by severe pancytopenia and a decline in healthy blood cell generation system. Studies conducted in our laboratory revealed that the primitive Sca-1+ BM-HSCs (bone marrow hematopoietic stem cell) are significantly affected in experimental Aplastic animals pretreated with chemotherapeutic drugs (Busulfan and Cyclophosphamide) and there is increased Caspase-3 activity with consecutive high Annexin-V positivity leading to premature apoptosis in the bone marrow hematopoietic stem cell population in Aplastic condition. The Sca-1bright, that is, “more primitive” BM-HSC population was more affected than the “less primitive” BM-HSC Sca-1dim  population. The decreased cell population and the receptor expression were directly associated with an empty and deranged marrow microenvironment, which is evident from scanning electron microscopy (SEM). The above experimental evidences hint toward the manipulation of receptor expression for the benefit of cytotherapy by primitive stem cell population in Aplastic anemia cases. PMID:21048851

  4. Handling Flight-Research Data In Real Time

    NASA Technical Reports Server (NTRS)

    Moore, Archie L.

    1988-01-01

    Researchers at widely separated locations able to participate in tests and analyze data immediately. Basic data-handling needs common: Communicates with vehicle, pilot, and test team; Acquires, computes, and displays data; knows exact location of research vehicle at all times. Continuing challenge for designers and operators of ground support facilities to perform tasks in real time and present integrated results to research team in real time. Paper presents several approaches to satisfaction of requirements of representative types of aircraft research programs at NASA Western Aeronautical Test Range of Ames Research Center.

  5. PREVENTING POLYGLUTAMINE-INDUCED ACTIVATION OF C-JUN DELAYS NEURONAL DYSFUNCTION IN A MOUSE MODEL OF SCA7 RETINOPATHY

    PubMed Central

    Merienne, Karine; Friedman, James; Akimoto, Masayuki; Abou-Sleymane, Gretta; Weber, Chantal; Swaroop, Anand; Trottier, Yvon

    2007-01-01

    We have approached the role of cellular stress in neurodegenerative diseases caused by polyglutamine expansion (polyQ) in the context of Spinocerebellar ataxia type 7 (SCA7) that includes retinal degeneration. Using the R7E mouse, in which polyQ-ataxin-7 is specifically over-expressed in rod photoreceptors, we previously showed that rod dysfunction correlated to moderate and prolonged activation of the JNK/c-Jun stress pathway. SCA7 retinopathy was also associated with reduced expression of rod-specific genes, including the transcription factor Nrl, which is essential for rod differentiation and function. Here, we report that R7E retinopathy is improved upon breeding with the JunAA knock-in mice, in which JNK-mediated activation of c-Jun is compromised. Expression of Nrl and its downstream targets, which are involved in phototranduction, are partially restored in the JunAA-R7E mice. We further show that c-Jun can directly repress the transcription of Nrl. Our studies suggest that polyQ-induced cellular stress leads to repression of genes necessary for neuronal fate and function. PMID:17189700

  6. Xpa deficiency reduces CAG trinucleotide repeat instability in neuronal tissues in a mouse model of SCA1

    PubMed Central

    Hubert, Leroy; Lin, Yunfu; Dion, Vincent; Wilson, John H.

    2011-01-01

    Expansion of trinucleotide repeats (TNRs) is responsible for a number of human neurodegenerative disorders. The molecular mechanisms that underlie TNR instability in humans are not clear. Based on results from model systems, several mechanisms for instability have been proposed, all of which focus on the ability of TNRs to form alternative structures during normal DNA transactions, including replication, DNA repair and transcription. These abnormal structures are thought to trigger changes in TNR length. We have previously shown that transcription-induced TNR instability in cultured human cells depends on several genes known to be involved in transcription-coupled nucleotide excision repair (NER). We hypothesized that NER normally functions to destabilize expanded TNRs. To test this hypothesis, we bred an Xpa null allele, which eliminates NER, into the TNR mouse model for spinocerebellar ataxia type 1 (SCA1), which carries an expanded CAG repeat tract at the endogenous mouse Sca1 locus. We find that Xpa deficiency does not substantially affect TNR instability in either the male or female germline; however, it dramatically reduces CAG repeat instability in neuronal tissues—striatum, hippocampus and cerebral cortex—but does not alter CAG instability in kidney or liver. The tissue-specific effect of Xpa deficiency represents a novel finding; it suggests that tissue-to-tissue variation in CAG repeat instability arises, in part, by different underlying mechanisms. These results validate our original findings in cultured human cells and suggest that transcription may induce NER-dependent TNR instability in neuronal tissues in humans. PMID:21926083

  7. The GBT-SCA, a radiation tolerant ASIC for detector control and monitoring applications in HEP experiments

    NASA Astrophysics Data System (ADS)

    Caratelli, A.; Bonacini, S.; Kloukinas, K.; Marchioro, A.; Moreira, P.; De Oliveira, R.; Paillard, C.

    2015-03-01

    The future upgrades of the LHC experiments will increase the beam luminosity leading to a corresponding growth of the amounts of data to be treated by the data acquisition systems. To address these needs, the GBT (Giga-Bit Transceiver optical link [1,2]) architecture was developed to provide the simultaneous transfer of readout data, timing and trigger signals as well as slow control and monitoring data. The GBT-SCA ASIC, part of the GBT chip-set, has the purpose to distribute control and monitoring signals to the on-detector front-end electronics and perform monitoring operations of detector environmental parameters. In order to meet the requirements of different front-end ASICs used in the experiments, it provides various user-configurable interfaces capable to perform simultaneous operations. It is designed employing radiation tolerant design techniques to ensure robustness against SEUs and TID radiation effects and is implemented in a commercial 130 nm CMOS technology. This work presents the GBT-SCA architecture, the ASIC interfaces, the data transfer protocol, and its integration with the GBT optical link.

  8. Handling Qualities of Model Reference Adaptive Controllers with Varying Complexity for Pitch-Roll Coupled Failures

    NASA Technical Reports Server (NTRS)

    Schaefer, Jacob; Hanson, Curt; Johnson, Marcus A.; Nguyen, Nhan

    2011-01-01

    Three model reference adaptive controllers (MRAC) with varying levels of complexity were evaluated on a high performance jet aircraft and compared along with a baseline nonlinear dynamic inversion controller. The handling qualities and performance of the controllers were examined during failure conditions that induce coupling between the pitch and roll axes. Results from flight tests showed with a roll to pitch input coupling failure, the handling qualities went from Level 2 with the baseline controller to Level 1 with the most complex MRAC tested. A failure scenario with the left stabilator frozen also showed improvement with the MRAC. Improvement in performance and handling qualities was generally seen as complexity was incrementally added; however, added complexity usually corresponds to increased verification and validation effort required for certification. The tradeoff between complexity and performance is thus important to a controls system designer when implementing an adaptive controller on an aircraft. This paper investigates this relation through flight testing of several controllers of vary complexity.

  9. Ergonomic material-handling device

    DOEpatents

    Barsnick, Lance E.; Zalk, David M.; Perry, Catherine M.; Biggs, Terry; Tageson, Robert E.

    2004-08-24

    A hand-held ergonomic material-handling device capable of moving heavy objects, such as large waste containers and other large objects requiring mechanical assistance. The ergonomic material-handling device can be used with neutral postures of the back, shoulders, wrists and knees, thereby reducing potential injury to the user. The device involves two key features: 1) gives the user the ability to adjust the height of the handles of the device to ergonomically fit the needs of the user's back, wrists and shoulders; and 2) has a rounded handlebar shape, as well as the size and configuration of the handles which keep the user's wrists in a neutral posture during manipulation of the device.

  10. Tritium handling in vacuum systems

    SciTech Connect

    Gill, J.T.; Coffin, D.O.

    1986-10-01

    This report provides a course in Tritium handling in vacuum systems. Topics presented are: Properties of Tritium; Tritium compatibility of materials; Tritium-compatible vacuum equipment; and Tritium waste treatment.

  11. RTJ-303: Variable geometry, oblique wing supersonic aircraft

    NASA Technical Reports Server (NTRS)

    Antaran, Albert; Belete, Hailu; Dryzmkowski, Mark; Higgins, James; Klenk, Alan; Rienecker, Lisa

    1992-01-01

    This document is a preliminary design of a High Speed Civil Transport (HSCT) named the RTJ-303. It is a 300 passenger, Mach 1.6 transport with a range of 5000 nautical miles. It features four mixed-flow turbofan engines, variable geometry oblique wing, with conventional tail-aft control surfaces. The preliminary cost analysis for a production of 300 aircraft shows that flyaway cost would be 183 million dollars (1992) per aircraft. The aircraft uses standard jet fuel and requires no special materials to handle aerodynamic heating in flight because the stagnation temperatures are approximately 130 degrees Fahrenheit in the supersonic cruise condition. It should be stressed that this aircraft could be built with today's technology and does not rely on vague and uncertain assumptions of technology advances. Included in this report are sections discussing the details of the preliminary design sequence including the mission to be performed, operational and performance constraints, the aircraft configuration and the tradeoffs of the final choice, wing design, a detailed fuselage design, empennage design, sizing of tail geometry, and selection of control surfaces, a discussion on propulsion system/inlet choice and their position on the aircraft, landing gear design including a look at tire selection, tip-over criterion, pavement loading, and retraction kinematics, structures design including load determination, and materials selection, aircraft performance, a look at stability and handling qualities, systems layout including location of key components, operations requirements maintenance characteristics, a preliminary cost analysis, and conclusions made regarding the design, and recommendations for further study.

  12. Handling Qualities of Large Rotorcraft in Hover and Low Speed

    NASA Technical Reports Server (NTRS)

    Malpica, Carlos; Theodore, Colin R.; Lawrence , Ben; Blanken, Chris L.

    2015-01-01

    According to a number of system studies, large capacity advanced rotorcraft with a capability of high cruise speeds (approx.350 mph) as well as vertical and/or short take-off and landing (V/STOL) flight could alleviate anticipated air transportation capacity issues by making use of non-primary runways, taxiways, and aprons. These advanced aircraft pose a number of design challenges, as well as unknown issues in the flight control and handling qualities domains. A series of piloted simulation experiments have been conducted on the NASA Ames Research Center Vertical Motion Simulator (VMS) in recent years to systematically investigate the fundamental flight control and handling qualities issues associated with the characteristics of large rotorcraft, including tiltrotors, in hover and low-speed maneuvering.

  13. 150 Passenger Commercial Aircraft

    NASA Technical Reports Server (NTRS)

    Bucovsky, Adrian; Romli, Fairuz I.; Rupp, Jessica

    2002-01-01

    It has been projected that the need for a short-range mid-sized, aircraft is increasing. The future strategy to decrease long-haul flights will increase the demand for short-haul flights. Since passengers prefer to meet their destinations quickly, airlines will increase the frequency of flights, which will reduce the passenger load on the aircraft. If a point-to-point flight is not possible, passengers will prefer only a one-stop short connecting flight to their final destination. A 150-passenger aircraft is an ideal vehicle for these situations. It is mid-sized aircraft and has a range of 3000 nautical miles. This type of aircraft would market U.S. domestic flights or inter-European flight routes. The objective of the design of the 150-passenger aircraft is to minimize fuel consumption. The configuration of the aircraft must be optimized. This aircraft must meet CO2 and NOx emissions standards with minimal acquisition price and operating costs. This report contains all the work that has been performed for the completion of the design of a 150 passenger commercial aircraft. The methodology used is the Technology Identification, Evaluation, and Selection (TIES) developed at Georgia Tech Aerospace Systems Design laboratory (ASDL). This is an eight-step conceptual design process to evaluate the probability of meeting the design constraints. This methodology also allows for the evaluation of new technologies to be implemented into the design. The TIES process begins with defining the problem with a need established and a market targeted. With the customer requirements set and the target values established, a baseline concept is created. Next, the design space is explored to determine the feasibility and viability of the baseline aircraft configuration. If the design is neither feasible nor viable, new technologies can be implemented to open up the feasible design space and allow for a plausible solution. After the new technologies are identified, they must be evaluated

  14. Intelligent Control Approaches for Aircraft Applications

    NASA Technical Reports Server (NTRS)

    Gundy-Burlet, Karen; KrishnaKumar, K.; Soloway, Don; Kaneshige, John; Clancy, Daniel (Technical Monitor)

    2001-01-01

    This paper presents an overview of various intelligent control technologies currently being developed and studied under the Intelligent Flight Control (IFC) program at the NASA Ames Research Center. The main objective of the intelligent flight control program is to develop the next generation of flight controllers for the purpose of automatically compensating for a broad spectrum of damaged or malfunctioning aircraft components and to reduce control law development cost and time. The approaches being examined include: (a) direct adaptive dynamic inverse controller and (b) an adaptive critic-based dynamic inverse controller. These approaches can utilize, but do not require, fault detection and isolation information. Piloted simulation studies are performed to examine if the intelligent flight control techniques adequately: 1) Match flying qualities of modern fly-by-wire flight controllers under nominal conditions; 2) Improve performance under failure conditions when sufficient control authority is available; and 3) Achieve consistent handling qualities across the flight envelope and for different aircraft configurations. Results obtained so far demonstrate the potential for improving handling qualities and significantly increasing survivability rates under various simulated failure conditions.

  15. Toward therapeutic targets for SCA3: Insight into the role of Machado-Joseph disease protein ataxin-3 in misfolded proteins clearance.

    PubMed

    Li, Xiaoling; Liu, Hongmei; Fischhaber, Paula L; Tang, Tie-Shan

    2015-09-01

    Machado-Joseph disease (MJD, also known as spinocerebellar ataxia type 3, SCA3), an autosomal dominant neurological disorder, is caused by an abnormal expanded polyglutamine (polyQ) repeat in the ataxin-3 protein. The length of the expanded polyQ stretch correlates positively with the severity of the disease and inversely with the age at onset. To date, we cannot fully explain the mechanism underlying neurobiological abnormalities of this disease. Yet, accumulating reports have demonstrated the functions of ataxin-3 protein in the chaperone system, ubiquitin-proteasome system, and aggregation-autophagy, all of which suggest a role of ataxin-3 in the clearance of misfolded proteins. Notably, the SCA3 pathogenic form of ataxin-3 (ataxin-3(exp)) impairs the misfolded protein clearance via mechanisms that are either dependent or independent of its deubiquitinase (DUB) activity, resulting in the accumulation of misfolded proteins and the progressive loss of neurons in SCA3. Some drugs, which have been used as activators/inducers in the chaperone system, ubiquitin-proteasome system, and aggregation-autophagy, have been demonstrated to be efficacious in the relief of neurodegeneration diseases like Huntington's disease (HD), Parkinson's (PD), Alzheimer's (AD) as well as SCA3 in animal models and clinical trials, putting misfolded protein clearance on the list of potential therapeutic targets. Here, we undertake a comprehensive review of the progress in understanding the physiological functions of ataxin-3 in misfolded protein clearance and how the polyQ expansion impairs misfolded protein clearance. We then detail the preclinical studies targeting the elimination of misfolded proteins for SCA3 treatment. We close with future considerations for translating these pre-clinical results into therapies for SCA3 patients. PMID:26123252

  16. Twin tilt nacelle V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Eskey, M. A.; Wilson, S. B., III; Valckenaere, W.; Lareau, J. P.

    1984-01-01

    This paper describes the second government-conducted, piloted flight simulation of the Grumman Design 698 V/STOL (vertical and short takeoff and landing) aircraft. Emphasis is on the aircraft's handling qualities as rated by various NASA, Navy, and GAC pilots with flight experience ranging from CTOL (conventional take-off and landing) to V/STOL aircraft. The Design 698 had been modified to resolve the flight problems that were of most concern to the pilots in the first investigation (Phase I). Those problems included an adverse nonminimum phase (NMP) acceleration response in both the longitudinal and lateral axes, a large thrust-response lag, and adverse ground effects. The adverse NMP acceleration is an attribute of the vertical vanes (a Grumman patent) positioned in the fan exhaust flow. The primary modifications included using the vertical-vane deflection as a thrust spoiling method, the addition of the cross-shafted propulsion system, and the implementation of two velocity and attitude control modes (standard and precision) for speeds below 50 knots.

  17. Assessing Aircraft Susceptibility to Nonlinear Aircraft-Pilot Coupling/Pilot-Induced Oscillations

    NASA Technical Reports Server (NTRS)

    Hess, R.A.; Stout, P. W.

    1997-01-01

    A unified approach for assessing aircraft susceptibility to aircraft-pilot coupling (or pilot-induced oscillations) which was previously reported in the literature and applied to linear systems is extended to nonlinear systems, with emphasis upon vehicles with actuator rate saturation. The linear methodology provided a tool for predicting: (1) handling qualities levels, (2) pilot-induced oscillation rating levels and (3) a frequency range in which pilot-induced oscillations are likely to occur. The extension to nonlinear systems provides a methodology for predicting the latter two quantities. Eight examples are presented to illustrate the use of the technique. The dearth of experimental flight-test data involving systematic variation and assessment of the effects of actuator rate limits presently prevents a more thorough evaluation of the methodology.

  18. Pathfinder Aircraft in Flight

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Pathfinder research aircraft's wing structure was clearly defined as it soared under a clear blue sky during a test flight July 27, 1995, from Dryden Flight Research Center, Edwards, California. The center section and outer wing panels of the aircraft had ribs constructed of thin plastic foam, while the ribs in the inner wing panels are fabricated from lightweight composite material. Developed by AeroVironment, Inc., the Pathfinder was one of several unmanned aircraft being evaluated under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long- duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar- powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus

  19. Pathfinder aircraft in flight

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Pathfinder research aircraft's wing structure was clearly defined as it soared under a clear blue sky during a test flight July 27, 1995, from Dryden Flight Research Center, Edwards, California. The center section and outer wing panels of the aircraft had ribs constructed of thin plastic foam, while the ribs in the inner wing panels are fabricated from lightweight composite material. Developed by AeroVironment, Inc., the Pathfinder was one of several unmanned aircraft being evaluated under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus

  20. Approach path control for powered-lift STOL aircraft

    NASA Technical Reports Server (NTRS)

    Clymer, D. J.; Flora, C. C.

    1973-01-01

    A flight control system concept is defined for approach flightpath control of an augmentor wing (or similar) powered-lift STOL configuration. The proposed STOL control concept produces aircraft transient and steady-state control responses that are familiar to pilots of conventional jet transports, and has potential for good handling qualities ratings in all approach and landing phases. The effects of trailing-edge rate limits, real-engine dynamics, and atmospheric turbulence are considered in the study. A general discussion of STOL handling qualities problems and piloting techniques is included.

  1. 7 CFR 58.443 - Whey handling.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Procedures § 58.443 Whey handling. (a) Adequate sanitary facilities shall be provided for the handling of... sanitary manner in accordance with the procedures of this subpart as specified for handling milk and...

  2. 7 CFR 58.443 - Whey handling.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Procedures § 58.443 Whey handling. (a) Adequate sanitary facilities shall be provided for the handling of... sanitary manner in accordance with the procedures of this subpart as specified for handling milk and...

  3. Eagle RTS: A design for a regional transport aircraft

    NASA Technical Reports Server (NTRS)

    Bryer, Paul; Buckles, Jon; Lemke, Paul; Peake, Kirk

    1992-01-01

    This university design project concerns the Eagle RTS (Regional Transport System), a 66 passenger, twin turboprop aircraft with a range of 836 nautical miles. It will operate with a crew of two pilots and two flight attendents. This aircraft will employ the use of aluminum alloys and composite materials to reduce the aircraft weight and increase aerodynamic efficiency. The Eagle RTS will use narrow body aerodynamics with a canard configuration to improve performance. Leading edge technology will be used in the cockpit to improve flight handling and safety. The Eagle RTS propulsion system will consist of two turboprop engines with a total thrust of approximately 6300 pounds, 3150 pounds thrust per engine, for the cruise configuration. The engines will be mounted on the aft section of the aircraft to increase passenger safety in the event of a propeller failure. Aft mounted engines will also increase the overall efficiency of the aircraft by reducing the aircraft's drag. The Eagle RTS is projected to have a takeoff distance of approximately 4700 feet and a landing distance of 6100 feet. These distances will allow the Eagle RTS to land at the relatively short runways of regional airports.

  4. Aircraft and Ground Vehicle Winter Runway Friction Assessment

    NASA Technical Reports Server (NTRS)

    Yager, Thomas J.

    1999-01-01

    Some background information is given together with the scope and objectives of a 5-year, Joint Winter Runway Friction Measurement Program between the National Aeronautics & Space Administration (NASA), Transport Canada (TC), and the Federal Aviation Administration (FAA). Participants recently completed the fourth winter season of testing. The primary objective of this effort is to perform instrumented aircraft and ground vehicle tests aimed at identifying a common number that all the different ground vehicle devices would report. This number, denoted the International Runway Friction Index (IRFI) will be related to all types of aircraft stopping performance. The range of test equipment, the test sites, test results and accomplishments, the extent of the substantial friction database compiled, and future test plans will be described. Several related studies have also been implemented including the effects of contaminant type on aircraft impingement drag and the effectiveness of various runway and aircraft de-icing chemical types and application rates. New equipment and techniques to measure surface frictional properties are also described. The status of an international friction index calibration device for use in ensuring accuracy of ground vehicle friction measurements will also be discussed. NASA considers the success of this joint program critical in terms of ensuring adequate ground handling capability in adverse weather conditions for future aircraft being designed and developed as well as improving the safety of current aircraft ground operations.

  5. Aircraft noise synthesis system

    NASA Technical Reports Server (NTRS)

    Mccurdy, David A.; Grandle, Robert E.

    1987-01-01

    A second-generation Aircraft Noise Synthesis System has been developed to provide test stimuli for studies of community annoyance to aircraft flyover noise. The computer-based system generates realistic, time-varying, audio simulations of aircraft flyover noise at a specified observer location on the ground. The synthesis takes into account the time-varying aircraft position relative to the observer; specified reference spectra consisting of broadband, narrowband, and pure-tone components; directivity patterns; Doppler shift; atmospheric effects; and ground effects. These parameters can be specified and controlled in such a way as to generate stimuli in which certain noise characteristics, such as duration or tonal content, are independently varied, while the remaining characteristics, such as broadband content, are held constant. The system can also generate simulations of the predicted noise characteristics of future aircraft. A description of the synthesis system and a discussion of the algorithms and methods used to generate the simulations are provided. An appendix describing the input data and providing user instructions is also included.

  6. High altitude reconnaissance aircraft

    NASA Technical Reports Server (NTRS)

    Yazdo, Renee Anna; Moller, David

    1990-01-01

    At the equator the ozone layer ranges from 65,000 to 130,000 plus feet, which is beyond the capabilities of the ER-2, NASA's current high altitude reconnaissance aircraft. The Universities Space Research Association, in cooperation with NASA, is sponsoring an undergraduate program which is geared to designing an aircraft that can study the ozone layer at the equator. This aircraft must be able to cruise at 130,000 feet for six hours at Mach 0.7, while carrying 3,000 lbs. of payload. In addition, the aircraft must have a minimum range of 6,000 miles. In consideration of the novel nature of this project, the pilot must be able to take control in the event of unforeseen difficulties. Three aircraft configurations were determined to be the most suitable - a joined-wing, a biplane, and a twin-boom conventional airplane. The performance of each configuration was analyzed to investigate the feasibility of the project.

  7. IDENTIFICATION OF AIRCRAFT HAZARDS

    SciTech Connect

    K.L. Ashley

    2005-03-23

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in the ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2004, Section 6.4.1). That determination was conservatively based on limited knowledge of flight data in the area of concern and on crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a Monitored Geologic Repository (MGR) at Yucca Mountain using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987, Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. NUREG-0800 is being used here as a reference because some of the same considerations apply. The intended use of this report is to provide inputs for further screening and analysis of the identified aircraft hazards based on the criteria that apply to Category 1 and 2 event sequence analyses as defined in 10 CFR 63.2 (see Section 4). The scope of this technical report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the MGR at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (see Section 7).

  8. Identification of Aircraft Hazards

    SciTech Connect

    K. Ashley

    2006-12-08

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2005 [DIRS 174235], Section 6.4.1). That determination was conservatively based upon limited knowledge of flight data in the area of concern and upon crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a monitored geologic repository (MGR) at Yucca Mountain, using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987 [DIRS 103124], Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. The intended use of this report is to provide inputs for further screening and analysis of identified aircraft hazards based upon the criteria that apply to Category 1 and Category 2 event sequence analyses as defined in 10 CFR 63.2 [DIRS 176544] (Section 4). The scope of this report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the repository at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (Section 7).

  9. Aircraft Operations Classification System

    NASA Technical Reports Server (NTRS)

    Harlow, Charles; Zhu, Weihong

    2001-01-01

    Accurate data is important in the aviation planning process. In this project we consider systems for measuring aircraft activity at airports. This would include determining the type of aircraft such as jet, helicopter, single engine, and multiengine propeller. Some of the issues involved in deploying technologies for monitoring aircraft operations are cost, reliability, and accuracy. In addition, the system must be field portable and acceptable at airports. A comparison of technologies was conducted and it was decided that an aircraft monitoring system should be based upon acoustic technology. A multimedia relational database was established for the study. The information contained in the database consists of airport information, runway information, acoustic records, photographic records, a description of the event (takeoff, landing), aircraft type, and environmental information. We extracted features from the time signal and the frequency content of the signal. A multi-layer feed-forward neural network was chosen as the classifier. Training and testing results were obtained. We were able to obtain classification results of over 90 percent for training and testing for takeoff events.

  10. Aircraft control position indicator

    NASA Technical Reports Server (NTRS)

    Dennis, Dale V. (Inventor)

    1987-01-01

    An aircraft control position indicator was provided that displayed the degree of deflection of the primary flight control surfaces and the manner in which the aircraft responded. The display included a vertical elevator dot/bar graph meter display for indication whether the aircraft will pitch up or down, a horizontal aileron dot/bar graph meter display for indicating whether the aircraft will roll to the left or to the right, and a horizontal dot/bar graph meter display for indicating whether the aircraft will turn left or right. The vertical and horizontal display or displays intersect to form an up/down, left/right type display. Internal electronic display driver means received signals from transducers measuring the control surface deflections and determined the position of the meter indicators on each dot/bar graph meter display. The device allows readability at a glance, easy visual perception in sunlight or shade, near-zero lag in displaying flight control position, and is not affected by gravitational or centrifugal forces.

  11. Immunity-Based Aircraft Fault Detection System

    NASA Technical Reports Server (NTRS)

    Dasgupta, D.; KrishnaKumar, K.; Wong, D.; Berry, M.

    2004-01-01

    In the study reported in this paper, we have developed and applied an Artificial Immune System (AIS) algorithm for aircraft fault detection, as an extension to a previous work on intelligent flight control (IFC). Though the prior studies had established the benefits of IFC, one area of weakness that needed to be strengthened was the control dead band induced by commanding a failed surface. Since the IFC approach uses fault accommodation with no detection, the dead band, although it reduces over time due to learning, is present and causes degradation in handling qualities. If the failure can be identified, this dead band can be further A ed to ensure rapid fault accommodation and better handling qualities. The paper describes the application of an immunity-based approach that can detect a broad spectrum of known and unforeseen failures. The approach incorporates the knowledge of the normal operational behavior of the aircraft from sensory data, and probabilistically generates a set of pattern detectors that can detect any abnormalities (including faults) in the behavior pattern indicating unsafe in-flight operation. We developed a tool called MILD (Multi-level Immune Learning Detection) based on a real-valued negative selection algorithm that can generate a small number of specialized detectors (as signatures of known failure conditions) and a larger set of generalized detectors for unknown (or possible) fault conditions. Once the fault is detected and identified, an adaptive control system would use this detection information to stabilize the aircraft by utilizing available resources (control surfaces). We experimented with data sets collected under normal and various simulated failure conditions using a piloted motion-base simulation facility. The reported results are from a collection of test cases that reflect the performance of the proposed immunity-based fault detection algorithm.

  12. Up-Regulation of miRNA-21 Expression Promotes Migration and Proliferation of Sca-1+ Cardiac Stem Cells in Mice

    PubMed Central

    Zhou, Qingling; Sun, Qiang; Zhang, Yongshan; Teng, Fei; Sun, Jinhui

    2016-01-01

    Background This study, by regulating the expression level of microRNA-21 (miRNA-21) in antigen-1+ (Sca-1+) cardiac stem cells (CSCs), examined the role of miRNA-21 in migration, proliferation, and differentiation of Sca-1+ CSCs, and explored the use of miRNA-21 in treatment of heart-related diseases in mice. Material/Methods The CSCs of 20 healthy 2-month-old C57BL/6 mice were collected in our study. Immunomagnetic beads were used to separate and prepare pure Sca-1+ CSCs, which were further examined by flow cytometry. The samples were assigned to 4 groups: the blank group, the miRNA-21 mimic group, the miRNA-21 inhibitor group, and the negative control (NC) group. Quantitative real-time polymerase chain reaction (qRT-PCR), Transwell chamber assay, and the methyl thiazolylte-trazolium (MTT) assay were performed. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to measure the expression levels of GATA-4, MEF2c, TNI, and β-MHC differentiation-related genes. Results Immunomagnetic separation results indicated that Sca-1+ CSCs accounted for more than 87.4% of CSCs. RT-PCR results also showed that the expression level of miRNA-21 of the miRNA-21 mimic group was higher than those of the other groups (all P<0.05). Compared to the NC and the blank group, the migration of Sca-1+ CSCs was more active in the miRNA-21 mimic group and less active in the miRNA-21 inhibitor group (all P<0.05). Moreover, compared to the blank group, the proliferation of Sca-1+ CSCs was enhanced in the miRNA-21 mimic group and inhibited in the miRNA-21 inhibitor group (all P<0.05). The results of RT-PCR indicated that neither miRNA-21 mimics nor miR-21 inhibitors influenced the gene expression levels of GATA-4, MEF2c, TNI, or β-MHC. Conclusions Our study provides evidence that up-regulation of miRNA-21 can promote migration and proliferation of Sca-1+ CSCs to enhance the capacity of Sca-1+ CSCs to repair damaged myocardium, which may pave the way for therapeutic strategies

  13. Up-Regulation of miRNA-21 Expression Promotes Migration and Proliferation of Sca-1+ Cardiac Stem Cells in Mice.

    PubMed

    Zhou, Qingling; Sun, Qiang; Zhang, Yongshan; Teng, Fei; Sun, Jinhui

    2016-01-01

    BACKGROUND This study, by regulating the expression level of microRNA-21 (miRNA-21) in antigen-1+ (Sca-1+) cardiac stem cells (CSCs), examined the role of miRNA-21 in migration, proliferation, and differentiation of Sca-1+ CSCs, and explored the use of miRNA-21 in treatment of heart-related diseases in mice. MATERIAL AND METHODS The CSCs of 20 healthy 2-month-old C57BL/6 mice were collected in our study. Immunomagnetic beads were used to separate and prepare pure Sca-1+ CSCs, which were further examined by flow cytometry. The samples were assigned to 4 groups: the blank group, the miRNA-21 mimic group, the miRNA-21 inhibitor group, and the negative control (NC) group. Quantitative real-time polymerase chain reaction (qRT-PCR), Transwell chamber assay, and the methyl thiazolylte-trazolium (MTT) assay were performed. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to measure the expression levels of GATA-4, MEF2c, TNI, and β-MHC differentiation-related genes. RESULTS Immunomagnetic separation results indicated that Sca-1+ CSCs accounted for more than 87.4% of CSCs. RT-PCR results also showed that the expression level of miRNA-21 of the miRNA-21 mimic group was higher than those of the other groups (all P<0.05). Compared to the NC and the blank group, the migration of Sca-1+ CSCs was more active in the miRNA-21 mimic group and less active in the miRNA-21 inhibitor group (all P<0.05). Moreover, compared to the blank group, the proliferation of Sca-1+ CSCs was enhanced in the miRNA-21 mimic group and inhibited in the miRNA-21 inhibitor group (all P<0.05). The results of RT-PCR indicated that neither miRNA-21 mimics nor miR-21 inhibitors influenced the gene expression levels of GATA-4, MEF2c, TNI, or β-MHC. CONCLUSIONS Our study provides evidence that up-regulation of miRNA-21 can promote migration and proliferation of Sca-1+ CSCs to enhance the capacity of Sca-1+ CSCs to repair damaged myocardium, which may pave the way for therapeutic strategies

  14. Damage tolerance for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Lincoln, John W.

    1992-01-01

    The damage tolerance experience in the United States Air Force with military aircraft and in the commercial world with large transport category aircraft indicates that a similar success could be achieved in commuter aircraft. The damage tolerance process is described for the purpose of defining the approach that could be used for these aircraft to ensure structural integrity. Results of some of the damage tolerance assessments for this class of aircraft are examined to illustrate the benefits derived from this approach. Recommendations are given for future damage tolerance assessment of existing commuter aircraft and on the incorporation of damage tolerance capability in new designs.

  15. Flight evaluations of the effect of advanced control systems and displays on the handling qualities of a general aviation airplane.

    NASA Technical Reports Server (NTRS)

    Loschke, P. C.; Barber, M. R.; Jarvis, C. R.; Enevoldson, E. K.

    1972-01-01

    Flight tests have shown that, by means of improved displays and advanced control systems, it is possible to transform a typical light airplane into a flying machine that borders on being perfect from a handling-qualities standpoint. A flight-director display and an attitude-command control system used in combination transformed a vehicle with poor handling qualities during ILS approaches in turbulent air into a vehicle with extremely good handling qualities. The attitude-command control system also improved the ride qualities of the airplane. A rate-command control system was less beneficial than an attitude-command control system. Although this paper deals primarily with general aviation aircraft, the results presented pertain to other types of aircraft. Short-takeoff-and-landing (STOL) aircraft would be a natural application of the control systems because, as a result of their low speeds, they encounter many of the handling-qualities problems noted on light aircraft. The improved ride qualities should be of interest to all airline operations, and for STOL aircraft in particular, because of their prolonged exposure to low-altitude turbulence.

  16. Aircraft icing instrumentation: Unfilled needs. [rotary wing aircraft

    NASA Technical Reports Server (NTRS)

    Kitchens, P. F.

    1980-01-01

    A list of icing instrumentation requirements are presented. Because of the Army's helicopter orientation, many of the suggestions are specific to rotary wing aircraft; however, some of the instrumentation are also suitable for general aviation aircraft.

  17. Application of optimal input synthesis to aircraft parameter identification

    NASA Technical Reports Server (NTRS)

    Gupta, N. K.; Hall, W. E., Jr.; Mehra, R. K.

    1976-01-01

    The Frequency Domain Input Synthesis procedure is used in identifying the stability and control derivatives of an aircraft. By using a frequency-domain approach, one can handle criteria that are not easily handled by the time-domain approaches. Numerical results are presented for optimal elevator deflections to estimate the longitudinal stability and control derivatives subject to root-mean square constraints on the input. The applicability of the steady state optimal inputs to finite duration flight testing is investigated. The steady state approximation of frequency-domain synthesis is good for data lengths greater than two time cycles for the short period mode of the aircraft longitudinal motions. Phase relationships between different frequency components become important for shorter data lengths. The frequency domain inputs are shown to be much better than the conventional doublet inputs.

  18. Emissions from queuing aircraft

    SciTech Connect

    Segal, H.

    1980-01-01

    The ability of the FAA (U.S. Federal Aviation Administration) Simplex mathematical model, which employs a simple point-source algorithm with provisions for selecting a particular plume height and initial box size for each aircraft being analyzed, to predict air quality through modeling emissions released from queuing aircraft was verified by measurements of carbon monoxide emissions from such aircraft during a five-day period at Los Angeles International Airport. The model predicted carbon monoxide concentrations of 4 ppm (National Ambient Air Quality Standard limit value is 35 ppm) at expected populated locations during the highest activity hour monitored. This study should also apply to other engine exhaust gases such as NO/sub x/.

  19. Transport aircraft accident dynamics

    NASA Technical Reports Server (NTRS)

    Cominsky, A.

    1982-01-01

    A study was carried out of 112 impact survivable jet transport aircraft accidents (world wide) of 27,700 kg (60,000 lb.) aircraft and up extending over the last 20 years. This study centered on the effect of impact and the follow-on events on aircraft structures and was confined to the approach, landing and takeoff segments of the flight. The significant characteristics, frequency of occurrence and the effect on the occupants of the above data base were studied and categorized with a view to establishing typical impact scenarios for use as a basis of verifying the effectiveness of potential safety concepts. Studies were also carried out of related subjects such as: (1) assessment of advanced materials; (2) human tolerance to impact; (3) merit functions for safety concepts; and (4) impact analysis and test methods.

  20. Scaling aircraft noise perception.

    NASA Technical Reports Server (NTRS)

    Ollerhead, J. B.

    1973-01-01

    Following a brief review of the background to the study, an extensive experiment is described which was undertaken to assess the practical differences between numerous alternative methods for calculating the perceived levels of individual aircraft flyover wounds. One hundred and twenty recorded sounds, including jets, turboprops, piston aircraft and helicopters were rated by a panel of subjects in a pair comparison test. The results were analyzed to evaluate a number of noise rating procedures, in terms of their ability to accurately estimate both relative and absolute perceived noise levels over a wider dynamic range (84-115 dB SPL) than had generally been used in previous experiments. Performances of the different scales were examined in detail for different aircraft categories, and the merits of different band level summation procedures, frequency weighting functions, duration and tone corrections were investigated.

  1. Alternative aircraft fuels technology

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1976-01-01

    NASA is studying the characteristics of future aircraft fuels produced from either petroleum or nonpetroleum sources such as oil shale or coal. These future hydrocarbon based fuels may have chemical and physical properties that are different from present aviation turbine fuels. This research is aimed at determining what those characteristics may be, how present aircraft and engine components and materials would be affected by fuel specification changes, and what changes in both aircraft and engine design would be required to utilize these future fuels without sacrificing performance, reliability, or safety. This fuels technology program was organized to include both in-house and contract research on the synthesis and characterization of fuels, component evaluations of combustors, turbines, and fuel systems, and, eventually, full-scale engine demonstrations. A review of the various elements of the program and significant results obtained so far are presented.

  2. Pathfinder aircraft in flight

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The unique Pathfinder solar-powered flying wing, is shown during a checkout flight from the Dryden Flight Research Center, Edwards, California. This two-hour low-altitude flight over Rogers Dry Lake, Nov. 19, 1996, served to test aircraft systems and functional procedures, according to officials of AeroVironment, Inc., Pathfinder's developer and operator. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

  3. Pathfinder aircraft flight

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Pathfinder research aircraft's wing structure is clearly defined as it soars under a clear blue sky during a test flight from Dryden Flight Research Center, Edwards, California, in November of 1996. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

  4. Aircraft surface coatings

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Liquid, spray on elastomeric polyurethanes are selected and investigated as best candidates for aircraft external protective coatings. Flight tests are conducted to measure drag effects of these coatings compared to paints and a bare metal surface. The durability of two elastometric polyurethanes are assessed in airline flight service evaluations. Laboratory tests are performed to determine corrosion protection properties, compatibility with aircraft thermal anti-icing systems, the effect of coating thickness on erosion durability, and the erosion characteristics of composite leading edges-bare and coated. A cost and benefits assessment is made to determine the economic value of various coating configurations to the airlines.

  5. Aircraft Flutter Testing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Wilmer Reed gained international recognition for his innovative research, contributions and patented ideas relating to flutter and aeroelasticity of aerospace vehicles at Langley Research Center. In the early 1980's, Reed retired from Langley and joined the engineering staff of Dynamic Engineering Inc. While at DEI, Reed conceived and patented the DEI Flutter Exciter, now used world-wide in flight flutter testing of new or modified aircraft designs. When activated, the DEI Flutter Exciter alternately deflects the airstream upward and downward in a rapid manner, creating a force similar to that produced by an oscillating trailing edge flap. The DEI Flutter Exciter is readily adaptable to a variety of aircraft.

  6. Aircraft Laminar Flow Control

    NASA Technical Reports Server (NTRS)

    Joslin, Ronald D.

    1998-01-01

    Aircraft laminar flow control (LFC) from the 1930's through the 1990's is reviewed and the current status of the technology is assessed. Examples are provided to demonstrate the benefits of LFC for subsonic and supersonic aircraft. Early studies related to the laminar boundary-layer flow physics, manufacturing tolerances for laminar flow, and insect-contamination avoidance are discussed. LFC concept studies in wind-tunnel and flight experiments are the major focus of the paper. LFC design tools are briefly outlined for completeness.

  7. Alternative aircraft fuels

    NASA Technical Reports Server (NTRS)

    Longwell, J. P.; Grobman, J. S.

    1977-01-01

    The efficient utilization of fossil fuels by future jet aircraft may necessitate the broadening of current aviation turbine fuel specifications. The most significant changes in specifications would be an increased aromatics content and a higher final boiling point in order to minimize refinery energy consumption and costs. These changes would increase the freezing point and might lower the thermal stability of the fuel, and could cause increased pollutant emissions, increased combustor liner temperatures, and poorer ignition characteristics. The effects that broadened specification fuels may have on present-day jet aircraft and engine components and the technology required to use fuels with broadened specifications are discussed.

  8. Aircraft engine pollution reduction

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1972-01-01

    The effect of engine operation on the types and levels of the major aircraft engine pollutants is described and the major factors governing the formation of these pollutants during the burning of hydrocarbon fuel are discussed. Methods which are being explored to reduce these pollutants are discussed and their application to several experimental research programs are pointed out. Results showing significant reductions in the levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen obtained from experimental combustion research programs are presented and discussed to point out potential application to aircraft engines.

  9. Aircraft engines. II

    SciTech Connect

    Smith, M.G. Jr.

    1988-01-01

    An account is given of the design features and prospective performance gains of ultrahigh bypass subsonic propulsion configurations and various candidate supersonic commercial aircraft powerplants. The supersonic types, whose enhanced thermodynamic cycle efficiency is considered critical to the economic viability of a second-generation SST, are the variable-cycle engine, the variable stream control engine, the turbine-bypass engine, and the supersonic-throughflow fan. Also noted is the turboramjet concept, which will be applicable to hypersonic aircraft whose airframe structure materials can withstand the severe aerothermodynamic conditions of this flight regime.

  10. Feedback Linearized Aircraft Control Using Dynamic Cell Structure

    NASA Technical Reports Server (NTRS)

    Jorgensen, C. C.

    1998-01-01

    A Dynamic Cell Structure (DCS ) Neural Network was developed which learns a topology representing network (TRN) of F-15 aircraft aerodynamic stability and control derivatives. The network is combined with a feedback linearized tracking controller to produce a robust control architecture capable of handling multiple accident and off-nominal flight scenarios. This paper describes network and its performance for accident scenarios including differential stabilator lock, soft sensor failure, control, stability derivative variation, and turbulence.

  11. Safe handling of large animals.

    PubMed

    Grandin, T

    1999-01-01

    The major causes of accidents with cattle, horses, and other grazing animals are: panic due to fear, male dominance aggression, or the maternal aggression of a mother protecting her newborn. Danger is inherent when handling large animals. Understanding their behavior patterns improves safety, but working with animals will never be completely safe. Calm, quiet handling and non-slip flooring are beneficial. Rough handling and excessive use of electric prods increase chances of injury to both people and animals, because fearful animals may jump, kick, or rear. Training animals to voluntarily cooperate with veterinary procedures reduces stress and improves safety. Grazing animals have a herd instinct, and a lone, isolated animal can become agitated. Providing a companion animal helps keep an animal calm. PMID:10329901

  12. Control Reallocation Strategies for Damage Adaptation in Transport Class Aircraft

    NASA Technical Reports Server (NTRS)

    Gundy-Burlet, Karen; Krishnakumar, K.; Limes, Greg; Bryant, Don

    2003-01-01

    This paper examines the feasibility, potential benefits and implementation issues associated with retrofitting a neural-adaptive flight control system (NFCS) to existing transport aircraft, including both cable/hydraulic and fly-by-wire configurations. NFCS uses a neural network based direct adaptive control approach for applying alternate sources of control authority in the presence of damage or failures in order to achieve desired flight control performance. Neural networks are used to provide consistent handling qualities across flight conditions, adapt to changes in aircraft dynamics and to make the controller easy to apply when implemented on different aircraft. Full-motion piloted simulation studies were performed on two different transport models: the Boeing 747-400 and the Boeing C-17. Subjects included NASA, Air Force and commercial airline pilots. Results demonstrate the potential for improving handing qualities and significantly increased survivability rates under various simulated failure conditions.

  13. Canada's first fixed-site aircraft noise monitoring system

    SciTech Connect

    Standen, N.M.

    1982-01-01

    The nature of aircraft noise management in Canada as it is presently evolving is discussed. The population of aircraft operating in Canada is similar to most western nations with regard to aircraft type. Canada's airport system includes major airports owned and operated by the federal Department of Transport (Transport Canada), airports owned and operated by provinces, municipalities or local commissions, and privately owned and operated airports, largely catering to general aviation. In addition, there are airports which are owned by Transport Canada, but operated by another agency. The consequence of this arrangement is that the major jet transport traffic is handled by airports which are owned and operated by either Transport Canada or another government agency.

  14. Fly-by-light aircraft closed loop test program

    NASA Astrophysics Data System (ADS)

    Halski, Don J.; Kessler, Bradley L.; Mattes, Robert E.; Wanamaker, Michael F.; Baumbick, Robert J.

    1995-05-01

    The Fly-by-Light Aircraft Closed-Loop Test (FACT) program is a flight test program sponsored by NASA-Lewis Research Center. The objectives of the FACT program are to demonstrate optical closed-loop control of flight critical and non-flight critical control surfaces and to demonstrate installation and maintenance aspects of fiber optics for application to commercial aircraft. This paper summarizes the FACT program optical maintenance, test architecture, and hardware developments to be flight tested on the NASA-Dryden F/A-18 Systems Research Aircraft (SRA). The modifications include replacing Fly-By-Wire (FBW) main ram feedback LVDT's with optic position sensors and an electro-optic decoder, and using electrical to optic converters and reverse for commands. The performance and handling qualities will be validated by laboratory, ground, and flight tests. The goal is to demonstrate system performance equivalent to the production system.

  15. Impacts of the EA and SCA patterns on the 20th century NAO-winter precipitation relationship in Europe

    NASA Astrophysics Data System (ADS)

    Comas-Bru, Laia; McDermott, Frank

    2013-04-01

    Much of the 20th century multi-decadal variability in the NAO-winter precipitation relationship over the N. Atlantic / European sector can be ascribed to the combined effects of the North Atlantic Oscillation (NAO) and either the East Atlantic pattern (EA) or the Scandinavian pattern (SCA). The NAO, EA and SCA indices employed here are defined as the three leading vectors of the cross-correlation matrix calculated from monthly sea-level pressure anomalies for 138 complete winters from the 20CRv2 dataset (Compo et al., 2011). Winter precipitation data over Europe for the entire 20th century is derived from the high resolution CRU-TS3.1 climate dataset (Mitchell and Jones, 2005). Here we document for the first time, that different NAO/EA and NAO/SCA combinations systematically influence winter precipitation conditions in Europe as a consequence of NAO dipole migrations. We find that the zero-correlated line of the NAO-winter precipitation relationship migrates southwards when the EA is in the opposite phase to the NAO. This can be related to a south-westwards migration of the NAO dipole under these conditions, as shown by teleconnectivity maps. Similarly, a clockwise movement of the NAO-winter climate correlated areas occurs when the phase of the SCA is opposite to that of the NAO, reflecting a clockwise movement of the NAO dipole under these conditions. An important implication of these migrations is that they influence the spatial and temporal stationarity of climate-NAO relationships. As a result, the link between winter precipitation patterns and the NAO is not straightforward in some regions such as the southern UK, Ireland and France. For instance, much of the inter-annual variability in the N-S winter precipitation gradient in the UK, originally attributed to inter-annual and inter-decadal variability of the NAO, reflects the migration of the NAO dipole, linked to linear combinations of the NAO and the EA. Our results indicate that when the N-S winter

  16. Optical communications for transport aircraft

    NASA Technical Reports Server (NTRS)

    Stengel, Robert

    1994-01-01

    Optical communications for transport aircraft are discussed. The problem involves: increasing demand for radio-frequency bands from an enlarging pool of users (aircraft, ground and sea vehicles, fleet operators, traffic control centers, and commercial radio and television); desirability of providing high-bandwidth dedicated communications to and from every aircraft in the National Airspace System; need to support communications, navigation, and surveillance for a growing number of aircraft; and improved meteorological observations by use of probe aircraft. The solution involves: optical signal transmission support very high data rates; optical transmission of signals between aircraft, orbiting satellites, and ground stations, where unobstructed line-of-sight is available; conventional radio transmissions of signals between aircraft and ground stations, where optical line-of-sight is unavailable; and radio priority given to aircraft in weather.

  17. Euclid Data Handling Design Solutions

    NASA Astrophysics Data System (ADS)

    Bogiatto, Roberto; Tramutola, Antonio; Maddaleno, Corrado; Maiorano, Elena; Colombo, Cyril

    2014-08-01

    Euclid is the next medium-class mission of ESA's Science Programme, to be launched by 2020. The objective of Euclid is to investigate dark energy and dark matter, essential but mysterious components of today's standard model of cosmology. The complete survey will comprise hundreds of thousands of images and several tens of Petabytes of data. The significant amount of scientific data to be stored on-board and transmitted to Ground, imposes some challenging spacecraft requirements leading to innovative design solutions for the data handling and on-board communications. After the mission presentation, the paper provides an overview of the Spacecraft avionics architecture and deepens the Euclid data handling design concept.

  18. Light aircraft sound transmission study

    NASA Technical Reports Server (NTRS)

    Atwal, M.; David, J.; Heitman, K.; Crocker, M. J.

    1983-01-01

    The revived interest in the design of propeller driven aircraft is based on increasing fuel prices as well as on the need for bigger short haul and commuter aircraft. A major problem encountered with propeller driven aircraft is propeller and exhaust noise that is transmitted through the fuselage sidewall structure. Part of the work which was conducted during the period April 1 to August 31, 1983, on the studies of sound transmission through light aircraft walls is presented.

  19. Aircraft community noise impact studies

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The objectives of the study are to: (1) conduct a program to determine the community noise impact of advanced technology engines when installed in a supersonic aircraft, (2) determine the potential reduction of community noise by flight operational techniques for the study aircraft, (3) estimate the community noise impact of the study aircraft powered by suppressed turbojet engines and by advanced duct heating turbofan engines, and (4) compare the impact of the two supersonic designs with that of conventional commercial DC-8 aircraft.

  20. The variable density aircraft concept

    NASA Technical Reports Server (NTRS)

    Davenport, A. C.

    1975-01-01

    In the variable density aircraft concept the aircraft's density is varied by varying its volume. This is accomplished by combining a variable volume hull, which is called the dynapod, with intrinsic means for the controlled variation of a mass of working fluid or substance within the aircraft. The dynapod is a hinged structure and follows the volumetric variations of the working fluid. The result is a variable density hull, which with the attachment of power plants, etc., becomes a variable density aircraft.

  1. Bibliography for aircraft parameter estimation

    NASA Technical Reports Server (NTRS)

    Iliff, Kenneth W.; Maine, Richard E.

    1986-01-01

    An extensive bibliography in the field of aircraft parameter estimation has been compiled. This list contains definitive works related to most aircraft parameter estimation approaches. Theoretical studies as well as practical applications are included. Many of these publications are pertinent to subjects peripherally related to parameter estimation, such as aircraft maneuver design or instrumentation considerations.

  2. Aircraft noise prediction

    NASA Astrophysics Data System (ADS)

    Filippone, Antonio

    2014-07-01

    This contribution addresses the state-of-the-art in the field of aircraft noise prediction, simulation and minimisation. The point of view taken in this context is that of comprehensive models that couple the various aircraft systems with the acoustic sources, the propagation and the flight trajectories. After an exhaustive review of the present predictive technologies in the relevant fields (airframe, propulsion, propagation, aircraft operations, trajectory optimisation), the paper addresses items for further research and development. Examples are shown for several airplanes, including the Airbus A319-100 (CFM engines), the Bombardier Dash8-Q400 (PW150 engines, Dowty R408 propellers) and the Boeing B737-800 (CFM engines). Predictions are done with the flight mechanics code FLIGHT. The transfer function between flight mechanics and the noise prediction is discussed in some details, along with the numerical procedures for validation and verification. Some code-to-code comparisons are shown. It is contended that the field of aircraft noise prediction has not yet reached a sufficient level of maturity. In particular, some parametric effects cannot be investigated, issues of accuracy are not currently addressed, and validation standards are still lacking.

  3. Aircraft Wake RCS Measurement

    NASA Technical Reports Server (NTRS)

    Gilson, William H.

    1994-01-01

    A series of multi-frequency radar measurements of aircraft wakes at altitudes of 5,000 to 25,00 ft. were performed at Kwajalein, R.M.I., in May and June of 1990. Two aircraft were tested, a Learjet 35 and a Lockheed C-5A. The cross-section of the wake of the Learjet was too small for detection at Kwajalein. The wake of the C-5A, although also very small, was detected and measured at VHF, UHF, L-, S-, and C-bands, at distances behind the aircraft ranging from about one hundred meters to tens of kilometers. The data suggest that the mechanism by which aircraft wakes have detectable radar signatures is, contrary to previous expectations, unrelated to engine exhaust but instead due to turbulent mixing by the wake vortices of pre-existing index of refraction gradients in the ambient atmosphere. These measurements were of necessity performed with extremely powerful and sensitive instrumentation radars, and the wake cross-section is too small for most practical applications.

  4. Counterrotating aircraft propulsor blades

    NASA Technical Reports Server (NTRS)

    Nelson, Joey L. (Inventor); Elston, III, Sidney B. (Inventor); Tseng, Wu-Yang (Inventor); Hemsworth, Martin C. (Inventor)

    1993-01-01

    A propulsor blade for an aircraft engine includes an airfoil section formed in the shape of a scimitar. A metallic blade spar is interposed between opposed surfaces of the blade and is bonded to the surfaces to establish structural integrity of the blade. The metallic blade spar includes a root end allowing attachment of the blade to the engine.

  5. Counterrotating aircraft propulsor blades

    NASA Technical Reports Server (NTRS)

    Nelson, Joey L. (Inventor); Elston, III, Sidney B. (Inventor); Tseng, Wu-Yang (Inventor); Hemsworth, Martin C. (Inventor)

    1988-01-01

    A propulsor blade for an aircraft engine includes an airfoil section formed in the shape of a scimitar. A metallic blade spar is interposed between opposed surfaces of the blade and is bonded to the surfaces to establish structural integrity of the blade. The metallic blade spar includes a root end allowing attachment of the blade to the engine.

  6. Robots for Aircraft Maintenance

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Marshall Space Flight Center charged USBI (now Pratt & Whitney) with the task of developing an advanced stripping system based on hydroblasting to strip paint and thermal protection material from Space Shuttle solid rocket boosters. A robot, mounted on a transportable platform, controls the waterjet angle, water pressure and flow rate. This technology, now known as ARMS, has found commercial applications in the removal of coatings from jet engine components. The system is significantly faster than manual procedures and uses only minimal labor. Because the amount of "substrate" lost is minimal, the life of the component is extended. The need for toxic chemicals is reduced, as is waste disposal and human protection equipment. Users of the ARMS work cell include Delta Air Lines and the Air Force, which later contracted with USBI for development of a Large Aircraft Paint Stripping system (LARPS). LARPS' advantages are similar to ARMS, and it has enormous potential in military and civil aircraft maintenance. The technology may also be adapted to aircraft painting, aircraft inspection techniques and paint stripping of large objects like ships and railcars.

  7. Aircraft adaptive learning control

    NASA Technical Reports Server (NTRS)

    Lee, P. S. T.; Vanlandingham, H. F.

    1979-01-01

    The optimal control theory of stochastic linear systems is discussed in terms of the advantages of distributed-control systems, and the control of randomly-sampled systems. An optimal solution to longitudinal control is derived and applied to the F-8 DFBW aircraft. A randomly-sampled linear process model with additive process and noise is developed.

  8. Ozone and aircraft operations

    NASA Technical Reports Server (NTRS)

    Perkins, P. J.

    1981-01-01

    The cabin ozone problem is discussed. Cabin ozone in terms of health effects, the characteristics of ozone encounters by aircraft, a brief history of studies to define the problem, corrective actions taken, and possible future courses of action are examined. It is suggested that such actions include avoiding high ozone concentrations by applying ozone forecasting in flight planning procedures.

  9. Visual Data Exploration and Analysis - Report of the VisualizationBreakout Session at the 2003 SCaLeS Workshop - Volume II

    SciTech Connect

    Bethel, E. Wes; Frank, Randall; Fulcomer, Samuel; Hansen, Chuck; Joy, Ken; Kohl, Jim; Middleton, Don

    2004-01-12

    This document is the report from the Visualization breakoutsession at the SCaLeS (Science Case for Large-scale Simulation) workshopheld in 2003 in Bethesda, MD. The document presents current researchchallenges in visualization of large-scale scientific data.

  10. Sphingosylphosphorylcholine promotes the differentiation of resident Sca-1 positive cardiac stem cells to cardiomyocytes through lipid raft/JNK/STAT3 and β-catenin signaling pathways.

    PubMed

    Li, Wenjing; Liu, Honghong; Liu, Pingping; Yin, Deling; Zhang, Shangli; Zhao, Jing

    2016-07-01

    Resident cardiac Sca-1-positive (+) stem cells may differentiate into cardiomyocytes to improve the function of damaged hearts. However, little is known about the inducers and molecular mechanisms underlying the myogenic conversion of Sca-1(+) stem cells. Here we report that sphingosylphosphorylcholine (SPC), a naturally occurring bioactive lipid, induces the myogenic conversion of Sca-1(+) stem cells, as evidenced by the increased expression of cardiac transcription factors (Nkx2.5 and GATA4), structural proteins (cardiac Troponin T), transcriptional enhancer (Mef2c) and GATA4 nucleus translocation. First, SPC activated JNK and STAT3, and the JNK inhibitor SP600125 or STAT3 inhibitor stattic impaired the SPC-induced expression of cardiac transcription factors and GATA4 nucleus translocation, which suggests that JNK and STAT3 participated in SPC-promoted cardiac differentiation. Moreover, STAT3 activation was inhibited by SP600125, whereas JNK was inhibited by β-cyclodextrin as a lipid raft breaker, which indicates a lipid raft/JNK/STAT3 pathway involved in SPC-induced myogenic transition. β-Catenin, degraded by activated GSK3β, was inhibited by SPC. Furthermore, GSK3β inhibitors weakened but the β-catenin inhibitor promoted SPC-induced differentiation. We found no crosstalk between the lipid raft/JNK/STAT3 and β-catenin pathway. Our study describes a lipid, SPC, as an endogenic inducer of myogenic conversion in Sca-1(+) stem cells with low toxicity and high efficiency for uptake. PMID:27066979

  11. Multimodal electrophysiologic follow-up study in 3 mutated but presymptomatic members of a spinocerebellar ataxia type 1 (SCA1) family.

    PubMed

    Ragno, M; Perretti, A C; Castaldo, I; Scarcella, M; Acciarri, S; Manganelli, F; Santoro, L

    2005-06-01

    The objective was to determine the progression of nervous system involvement in spinocerebellar ataxia type 1 (SCA1). Three presymptomatic members of an Italian SCA1 family underwent molecular analysis and showed the SCA1 mutation. They were defined as "at risk/mutated" individuals. A clinical and electrophysiologic 7-9 year follow-up was performed. The Inherited Ataxia Progression Scale was used for clinical staging. Sensory and motor conduction velocities, somatosensory evoked potentials and transcranial magnetic stimulation were performed at least three times in each subject. Clinical examination showed the early corticospinal pathway involvement. Electrophysiologic investigations confirmed that at the asymptomatic stage only magnetic motor cortex stimulation was abnormal and rapidly worsened with time. Somatosensory pathway studies showed a later involvement and a light sensory-motor neuropathy was the last electrophysiologic abnormality to be recognised. These data confirm that SCA1 phenotype is characterised by early and prevalent pyramidal tract involvement and that peripheral neuropathy is a late and moderate complication. PMID:15995822

  12. Revisions to V/STOL handling qualities criteria of AGARD report 408

    NASA Technical Reports Server (NTRS)

    Anderson, S. B.; Schroers, L. G.

    1972-01-01

    A brief review of selected handling qualities criteria for V/STOL aircraft shows that although a clearer understanding of the requirements for controversial areas such as roll control power, vertical flight path control, and transition is in hand, considerably more research is needed to refine these criteria for operational IFR activity. Because many items interact to influence the pilots' overall impression of the aircraft's behaviour, additional work of a systematic nature must be done to clarify this aspect. A better definition of a gust model which includes discrete gust effects is needed to firm up criteria for both hover and STOL operation.

  13. Expert Systems and Document Handling.

    ERIC Educational Resources Information Center

    Edmonds, Ernest

    1987-01-01

    Describes significant attributes of expert systems, contrasts them to conventional computer systems, and provides an overview of the R1 expert system used by Digital Equipment Corporation (DEC) to put together operational systems that meet customers' requirements. Document handling, particularly pictures and images in documents, is also briefly…

  14. Portable vacuum object handling device

    DOEpatents

    Anderson, Gordon H.

    1983-08-09

    The disclosure relates to a portable device adapted to handle objects which are not to be touched by hand. A piston and bore wall form a vacuum chamber communicating with an adaptor sealably engageable with an object to be lifted. The piston is manually moved and set to establish vacuum. A valve is manually actuatable to apply the vacuum to lift the object.

  15. Non-contact handling device

    DOEpatents

    Reece, Mark; Knorovsky, Gerald A.; MacCallum, Danny O.

    2007-05-15

    A pressurized fluid handling nozzle has a body with a first end and a second end, a fluid conduit and a recess at the second end. The first end is configured for connection to a pressurized fluid source. The fluid conduit has an inlet at the first end and an outlet at the recess. The nozzle uses the Bernoulli effect for lifting a part.

  16. [Hygienic handling in cardiac surgery].

    PubMed

    Shimasaki, T; Masaoka, T; Hirooka, S; Abe, H; Watanabe, T; Washio, M

    1993-04-01

    Some points regarding the hygienic handling in cardiac surgery are mentioned. The sternal infection or mediastinitis is still one of the most important complications after cardiac operation especially when ITA is used for CABG. After we paid much attention to these points, the postoperative sternal infection has decreased obviously. PMID:8468855

  17. Piloting considerations for terminal area operations of civil tiltwing and tiltrotor aircraft

    NASA Technical Reports Server (NTRS)

    Hindson, William S.; Hardy, Gordon H.; Tucker, George E.; Decker, William A.

    1993-01-01

    The existing body of research to investigate airworthiness, performance, handling, and operational requirements for STOL and V/STOL aircraft was reviewed for its applicability to the tiltrotor and tiltwing design concepts. The objective of this study was to help determine the needs for developing civil certification criteria for these aircraft concepts. Piloting tasks that were considered included configuration and thrust vector management, glidepath control, deceleration to hover, and engine failure procedures. Flight control and cockpit display systems that have been found necessary to exploit the low-speed operating characteristics of these aircraft are described, and beneficial future developments are proposed.

  18. Two and three dimensional systems for computer aided geometric design of aircraft surface and components

    NASA Astrophysics Data System (ADS)

    Aryeh, F.

    1982-01-01

    Three interactive software systems dealing with the computerized definition, storage and handling of aircraft geometric shapes and entities in a multidisciplinary design environment are presented. The systems are operated in an interactive fashion via use of low cost graphic display terminals driven by a remote computer in a time sharing mode. GEODEF is a system for interactive definition of complex aircraft surfaces, GEOBASE is a system for interrogation and manipulation of a computerized aircraft geometry data base, and DOG is a 3-D detailed structural and mechanical part definition system.

  19. Development of control laws for a flight test maneuver autopilot for an F-15 aircraft

    NASA Technical Reports Server (NTRS)

    Alag, G. S.; Duke, E. L.

    1985-01-01

    An autopilot can be used to provide precise control to meet the demanding requirements of flight research maneuvers with high-performance aircraft. The development of control laws within the context of flight test maneuver requirements is discussed. The control laws are developed using eigensystem assignment and command generator tracking. The eigenvalues and eigenvectors are chosen to provide the necessary handling qualities, while the command generator tracking enables the tracking of a specified state during the maneuver. The effectiveness of the control laws is illustrated by their application to an F-15 aircraft to ensure acceptable aircraft performance during a maneuver.

  20. A progress report on the development of an augmentor wing jet STOL research aircraft.

    NASA Technical Reports Server (NTRS)

    Quigley, H. C.; Sinclair, S. R. M.; Nark, T. C., Jr.; O'Keefe, J. V.

    1971-01-01

    The development of the aircraft has progressed to the point where the design of the modifications to the de Havilland C-8A Buffalo is complete and the engines are being tested. The predicted performance shows that the aircraft will be able to take off and land in less than 1500 ft. Simulation studies indicate that the handling qualities of the aircraft, with stability augmentation, will be acceptable for STOL research missions. Special techniques were required, however, for flight path control and transition from cruise to landing configuration .

  1. Adaptive Failure Compensation for Aircraft Flight Control Using Engine Differentials: Regulation

    NASA Technical Reports Server (NTRS)

    Yu, Liu; Xidong, Tang; Gang, Tao; Joshi, Suresh M.

    2005-01-01

    The problem of using engine thrust differentials to compensate for rudder and aileron failures in aircraft flight control is addressed in this paper in a new framework. A nonlinear aircraft model that incorporates engine di erentials in the dynamic equations is employed and linearized to describe the aircraft s longitudinal and lateral motion. In this model two engine thrusts of an aircraft can be adjusted independently so as to provide the control flexibility for rudder or aileron failure compensation. A direct adaptive compensation scheme for asymptotic regulation is developed to handle uncertain actuator failures in the linearized system. A design condition is specified to characterize the system redundancy needed for failure compensation. The adaptive regulation control scheme is applied to the linearized model of a large transport aircraft in which the longitudinal and lateral motions are coupled as the result of using engine thrust differentials. Simulation results are presented to demonstrate the effectiveness of the adaptive compensation scheme.

  2. Advanced ATC - An aircraft perspective

    NASA Technical Reports Server (NTRS)

    Credeur, L.; Williams, D. H.; Howell, W. E.; Spitzer, C. R.

    1986-01-01

    The principal operational improvements desired by commercial aircraft operators in the United States are efficient aircraft operations and delay reductions at the major terminals. This paper describes efforts underway within the Advanced Transport Operating Systems Program at the Langley Research Center to provide a technology basis for reducing delay while improving aircraft efficiency. The principal thrust is the development of time-based traffic control concepts which could be used within the framework of the upgraded National Airspace System and which would allow conventionally equipped aircraft to operate in a manner compatible with advanced aircraft.

  3. Turboprop cargo aircraft systems study

    NASA Technical Reports Server (NTRS)

    Muehlbauer, J. C.; Hewell, J. G., Jr.; Lindenbaum, S. P.; Randall, C. C.; Searle, N.; Stone, R. G., Jr.

    1981-01-01

    The effects of using advanced turboprop propulsion systems to reduce the fuel consumption and direct operating costs of cargo aircraft were studied, and the impact of these systems on aircraft noise and noise prints around a terminal area was determined. Parametric variations of aircraft and propeller characteristics were investigated to determine their effects on noiseprint areas, fuel consumption, and direct operating costs. From these results, three aircraft designs were selected and subjected to design refinements and sensitivity analyses. Three competitive turbofan aircraft were also defined from parametric studies to provide a basis for comparing the two types of propulsion.

  4. Advanced ATC: An aircraft perspective

    NASA Technical Reports Server (NTRS)

    Credeur, Leonard; Williams, David H.; Howell, William E.; Spitzer, Cary R.

    1986-01-01

    The principal operational improvements desired by commercial aircraft operators in the United States are efficient aircraft operations and delay reductions at the major terminals. Efforts underway within the Advanced Transport Operating Systems Program at the Langley Research Center to provide a technology basis for reducing delay while improving aircraft efficiency are discussed. The principal thrust is the development of time-based traffic control concepts which could be used within the framework of the upgraded National Airspace System and which would allow conventionally equipped aircraft to operate in a manner compatible with advanced aircraft.

  5. Opposing effects of Sca-1(+) cell-based systemic FGF2 gene transfer strategy on lumbar versus caudal vertebrae in the mouse.

    PubMed

    Lau, K-H W; Chen, S-T; Wang, X; Mohan, S; Wergedal, J E; Kesavan, C; Srivastava, A K; Gridley, D S; Hall, S L

    2016-06-01

    Our previous work showed that a Sca-1(+) cell-based FGF2 therapy was capable of promoting robust increases in trabecular bone formation and connectivity on the endosteum of long bones. Past work reported that administration of FGF2 protein promoted bone formation in red marrow but not in yellow marrow. The issue as to whether the Sca-1(+) cell-based FGF2 therapy is effective in yellow marrow is highly relevant to its clinical potential for osteoporosis, as most red marrows in a person of an advanced age are converted to yellow marrows. Accordingly, this study sought to compare the osteogenic effects of this stem cell-based FGF2 therapy on red marrow-filled lumbar vertebrae with those on yellow marrow-filled caudal vertebrae of young adult W(41)/W(41) mice. The Sca-1(+) cell-based FGF2 therapy drastically increased trabecular bone formation in lumbar vertebrae, but the therapy not only did not promote bone formation but instead caused substantial loss of trabecular bone in caudal vertebrae. The lack of an osteogenic response was not due to insufficient engraftment of FGF2-expressing Sca-1(+) cells or inadequate FGF2 expression in caudal vertebrae. Previous studies have demonstrated that recipient mice of this stem cell-based FGF2 therapy developed secondary hyperparathyroidism and increased bone resorption. Thus, the loss of bone mass in caudal vertebrae might in part be due to an increase in resorption without a corresponding increase in bone formation. In conclusion, the Sca-1(+) cell-based FGF2 therapy is osteogenic in red marrow but not in yellow marrow. PMID:26934099

  6. A new humanized ataxin-3 knock-in mouse model combines the genetic features, pathogenesis of neurons and glia and late disease onset of SCA3/MJD.

    PubMed

    Switonski, Pawel M; Szlachcic, Wojciech J; Krzyzosiak, Wlodzimierz J; Figiel, Maciej

    2015-01-01

    Spinocerebellar ataxia type 3 (SCA3/MJD) is a neurodegenerative disease triggered by the expansion of CAG repeats in the ATXN3 gene. Here, we report the generation of the first humanized ataxin-3 knock-in mouse model (Ki91), which provides insights into the neuronal and glial pathology of SCA3/MJD. First, mutant ataxin-3 accumulated in cell nuclei across the Ki91 brain, showing diffused immunostaining and forming intranuclear inclusions. The humanized allele revealed expansion and contraction of CAG repeats in intergenerational transmissions. CAG mutation also exhibited age-dependent tissue-specific expansion, which was most prominent in the cerebellum, pons and testes of Ki91 animals. Moreover, Ki91 mice displayed neuroinflammatory processes, showing astrogliosis in the cerebellar white matter and the substantia nigra that paralleled the transcriptional deregulation of Serpina3n, a molecular sign of neurodegeneration and brain damage. Simultaneously, the cerebellar Purkinje cells in Ki91 mice showed neurodegeneration, a pronounced decrease in Calbindin D-28k immunoreactivity and a mild decrease in cell number, thereby modeling the degeneration of the cerebellum observed in SCA3. Moreover, these molecular and cellular neuropathologies were accompanied by late behavioral deficits in motor coordination observed in rotarod and static rod tests in heterozygous Ki91 animals. In summary, we created an ataxin-3 knock-in mouse model that combines the molecular and behavioral disease phenotypes with the genetic features of SCA3. This model will be very useful for studying the pathogenesis and responses to therapy of SCA3/MJD and other polyQ disorders. PMID:25301414

  7. Time scheduling of a mix of 4D equipped and unequipped aircraft

    NASA Technical Reports Server (NTRS)

    Tobias, L.

    1983-01-01

    In planning for a future automated air traffic system, it is necessary to confront the transition situation in which some percentage of the traffic must be handled by conventional means. A safe, efficient transition system is needed since initially not all aircraft will be able to respond to a more automated system. The specific problem addressed was that of time scheduling a mix of 4D-equipped aircraft (aircraft that can accurately meet a controller specified time schedule at selected way points in the terminal area) when operating in conjunction with unequipped aircraft (aircraft that require air traffic handling by means of standard vectoring techniques). First, a relationship between time separation and system capacity was developed. The time separations were incorporated into a set of scheduling algorithms which contain the required elements of flexibility needed for terminal-area operation, such as delaying aircraft and changing time separations. The problem of reducing the size of time separations allotted for vectored aircraft by means of computer assists to the controller was also addressed.

  8. STS-68 on Runway with 747 SCA/Columbia Ferry Flyby

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The space shuttle Endeavour receives a high-flying salute from its sister shuttle, Columbia, atop NASA's Shuttle Carrier Aircraft, shortly after Endeavor's landing 12 October 1994, at Edwards, California, to complete mission STS-68. Columbia was being ferried from the Kennedy Space Center, Florida, to Air Force Plant 42, Palmdale, California, where it will undergo six months of inspections, modifications, and systems upgrades. The STS-68 11-day mission was devoted to radar imaging of Earth's geological features with the Space Radar Laboratory. The orbiter is surrounded by equipment and personnel that make up the ground support convoy that services the space vehicles as soon as they land. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the

  9. Shuttle Endeavour Mated to 747 SCA Taxi to Runway for Delivery to Kennedy Space Center, Florida

    NASA Technical Reports Server (NTRS)

    1991-01-01

    NASA's 747 Shuttle Carrier Aircraft No. 911, with the space shuttle orbiter Endeavour securely mounted atop its fuselage, taxies to the runway to begin the ferry flight from Rockwell's Plant 42 at Palmdale, California, where the orbiter was built, to the Kennedy Space Center, Florida. At Kennedy, the space vehicle was processed and launched on orbital mission STS-49, which landed at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, 16 May 1992. NASA 911, the second modified 747 that went into service in November 1990, has special support struts atop the fuselage and internal strengthening to accommodate the added weight of the orbiters. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay

  10. Shuttle in Mate-Demate Device being Loaded onto SCA-747 - Rear View

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Evening light begins to fade at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, as technicians begin the task of mounting the Space Shuttle Atlantis atop NASA's 747 Shuttle Carrier Aircraft (NASA 911) for the ferry flight back to the Kennedy Space Center, Fla., following its STS-44 flight 24 November-1 December 1991. Post-flight servicing of the orbiters, and the mating operation is carried out at Dryden at the Mate-Demate Device, the large gantry-like structure that hoists the spacecraft to various levels during post-spaceflight processing and attachment to the 747. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle

  11. Shuttle Endeavour Mated to 747 SCA Takeoff for Delivery to Kennedy Space Center, Florida

    NASA Technical Reports Server (NTRS)

    1991-01-01

    NASA's 747 Shuttle Carrier Aircraft No. 911, with the space shuttle orbiter Endeavour securely mounted atop its fuselage, begins the ferry flight from Rockwell's Plant 42 at Palmdale, California, where the orbiter was built, to the Kennedy Space Center, Florida. At Kennedy, the space vehicle was processed and launched on orbital mission STS-49, which landed at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, 16 May 1992. NASA 911, the second modified 747 that went into service in November 1990, has special support struts atop the fuselage and internal strengthening to accommodate the added weight of the orbiters. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission

  12. Shuttle in Mate-Demate Device being Loaded onto SCA-747 - Side View

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Evening light begins to fade at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, as technicians begin the task of mounting the Space Shuttle Atlantis atop NASA's 747 Shuttle Carrier Aircraft (NASA #911) for the ferry flight back to the Kennedy Space Center, Fla., following its STS-44 flight 24 November-1 December 1991. Post-flight servicing of the orbiters, and the mating operation, is carried out at Dryden at the Mate-Demate Device (MDD), the large gantry-like structure that hoists the spacecraft to various levels during post-space flight processing and attachment to the 747. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space

  13. Shuttle in Mate-Demate Device being Loaded onto SCA-747

    NASA Technical Reports Server (NTRS)

    1991-01-01

    At NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, technicians begin the task of mounting the Space Shuttle Atlantis atop NASA's 747 Shuttle Carrier Aircraft (NASA #911) for the ferry flight back to the Kennedy Space Center, Florida, following its STS-44 flight 24 November - 1 December 1991. Post-flight servicing of the orbiters, and the mating operation, is carried out at Dryden at the Mate-Demate Device (MDD), the large gantry-like structure that hoists the spacecraft to various levels during post-space flight processing and attachment to the 747. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and

  14. A simulator investigation of parameters affecting helicopter handling qualities in air combat (HAC II)

    NASA Technical Reports Server (NTRS)

    Lewis, Michael S.; Mansur, M. Hossein; Chen, Robert T. N.

    1987-01-01

    The Helicopter Air Combat system was used to conduct a pilot simulation study investigating the handling qualities and flight characteristics required for helicopter air-to-air combat. Results indicate that a well-damped directional response, low sideforce caused by sideslip, and some effective dihedral are all desirable for weapon system performance, good handling qualities, and low pilot workload. An angular rate command system was favored over the attitude-type pitch and roll response for most applications, and an enhanced maneuver envelope size over that of current generation aircraft was found to be of advantage.

  15. Autonomous aircraft initiative study

    NASA Technical Reports Server (NTRS)

    Hewett, Marle D.

    1991-01-01

    The results of a consulting effort to aid NASA Ames-Dryden in defining a new initiative in aircraft automation are described. The initiative described is a multi-year, multi-center technology development and flight demonstration program. The initiative features the further development of technologies in aircraft automation already being pursued at multiple NASA centers and Department of Defense (DoD) research and Development (R and D) facilities. The proposed initiative involves the development of technologies in intelligent systems, guidance, control, software development, airborne computing, navigation, communications, sensors, unmanned vehicles, and air traffic control. It involves the integration and implementation of these technologies to the extent necessary to conduct selected and incremental flight demonstrations.

  16. Aircraft Design Software

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Successful commercialization of the AirCraft SYNThesis (ACSYNT) tool has resulted in the creation of Phoenix Integration, Inc. ACSYNT has been exclusively licensed to the company, an outcome of a seven year, $3 million effort to provide unique software technology to a focused design engineering market. Ames Research Center formulated ACSYNT and in working with the Virginia Polytechnic Institute CAD Laboratory, began to design and code a computer-aided design for ACSYNT. Using a Joint Sponsored Research Agreement, Ames formed an industry-government-university alliance to improve and foster research and development for the software. As a result of the ACSYNT Institute, the software is becoming a predominant tool for aircraft conceptual design. ACSYNT has been successfully applied to high- speed civil transport configuration, subsonic transports, and supersonic fighters.

  17. Aircraft engine pollution reduction.

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1972-01-01

    The effect of engine operation on the types and levels of the major aircraft engine pollutants is described and the major factors governing the formation of these pollutants during the burning of hydrocarbon fuel are discussed. Methods which are being explored to reduce these pollutants are discussed and their application to several experimental research programs are pointed out. Results showing significant reductions in the levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen obtained from experimental combustion research programs are presented and discussed to point out potential application to aircraft engines. An experimental program designed to develop and demonstrate these and other advanced, low pollution combustor design methods is described. Results that have been obtained to date indicate considerable promise for reducing advanced engine exhaust pollutants to levels significantly below current engines.

  18. Aircraft turbofan noise

    NASA Technical Reports Server (NTRS)

    Groeneweg, J. F.; Rice, E. J.

    1983-01-01

    Turbofan noise generation and suppression in aircraft engines are reviewed. The chain of physical processes which connect unsteady flow interactions with fan blades to far field noise is addressed. Mechanism identification and description, duct propagation, radiation and acoustic suppression are discussed. The experimental technique of fan inflow static tests are discussed. Rotor blade surface pressure and wake velocity measurements aid in the determination of the types and strengths of the generation mechanisms. Approaches to predicting or measuring acoustic mode content, optimizing treatment impedance to maximize attenuation, translating impedance into porous wall structure and interpreting far field directivity patterns are illustrated by comparisons of analytical and experimental results. The interdependence of source and acoustic treatment design to minimize far field noise is emphasized. Area requiring further research are discussed and the relevance of aircraft turbofan results to quieting other turbomachinery installations is addressed.

  19. Air pollution from aircraft

    NASA Technical Reports Server (NTRS)

    Heywood, J. B.; Fay, J. A.; Chigier, N. A.

    1979-01-01

    Forty-one annotated abstracts of reports generated at MIT and the University of Sheffield are presented along with summaries of the technical projects undertaken. Work completed includes: (1) an analysis of the soot formation and oxidation rates in gas turbine combustors, (2) modelling the nitric oxide formation process in gas turbine combustors, (3) a study of the mechanisms causing high carbon monoxide emissions from gas turbines at low power, (4) an analysis of the dispersion of pollutants from aircraft both around large airports and from the wakes of subsonic and supersonic aircraft, (5) a study of the combustion and flow characteristics of the swirl can modular combustor and the development and verification of NO sub x and CO emissions models, (6) an analysis of the influence of fuel atomizer characteristics on the fuel-air mixing process in liquid fuel spray flames, and (7) the development of models which predict the stability limits of fully and partially premixed fuel-air mixtures.

  20. Project report: Aircraft

    SciTech Connect

    Wuebbles, D.J.; Baughcum, S.; Metwally, M.; Seals, R.

    1994-04-01

    Analyses of scenarios of past and possible future emissions are an important aspect of assessing the potential environmental effects from aircraft, including the proposed high speed civil transport (HSCT). The development of a detailed three-dimensional database that accurately represents the integration of all aircraft emissions along realistic flight paths for such scenarios requires complex computational modeling capabilities. Such a detailed data set is required for the scenarios evaluated in this interim assessment. Within the NASA High-Speed Research Program, the Emissions Scenarios Committee provides a forum for identifying the required scenarios and evaluating the resulting database being developed with the advanced emissions modeling capabilities at the Boeing Company and McDonnell Douglas Corporation.

  1. Energy efficient aircraft engines

    NASA Technical Reports Server (NTRS)

    Chamberlin, R.; Miller, B.

    1979-01-01

    The three engine programs that constitute the propulsion portion of NASA's Aircraft Energy Efficiency Program are described, their status indicated, and anticipated improvements in SFC discussed. The three engine programs are (1) Engine Component Improvement--directed at current engines, (2) Energy Efficiency Engine directed at new turbofan engines, and (3) Advanced Turboprops--directed at technology for advanced turboprop--powered aircraft with cruise speeds to Mach 0.8. Unique propulsion system interactive ties to the airframe resulting from engine design features to reduce fuel consumption are discussed. Emphasis is placed on the advanced turboprop since it offers the largest potential fuel savings of the three propulsion programs and also has the strongest interactive ties to the airframe.

  2. Energy efficient aircraft engines

    NASA Technical Reports Server (NTRS)

    Chamberlin, R.; Miller, B.

    1979-01-01

    The three engine programs that constitute the propulsion portion of NASA's Aircraft Energy Efficiency Program are described, their status indicated, and anticipated improvements in SFC discussed. The three engine programs are: (1) engine component improvement, directed at current engines, (2) energy efficient engine, directed at new turbofan engines, and (3) advanced turboprops, directed at technology for advanced turboprop-powered aircraft with cruise speeds to Mach 0.8. Unique propulsion system interactive ties to the airframe resulting from engine design features to reduce fuel consumption are discussed. Emphasis is placed on the advanced turboprop since it offers the largest potential fuel savings of the three propulsion programs and also has the strongest interactive ties to the airframe.

  3. Portable vacuum object handling device

    DOEpatents

    Anderson, G.H.

    1983-08-09

    The disclosure relates to a portable device adapted to handle objects which are not to be touched by hand. A piston and bore wall form a vacuum chamber communicating with an adaptor sealably engageable with an object to be lifted. The piston is manually moved and set to establish vacuum. A valve is manually actuatable to apply the vacuum to lift the object. 1 fig.

  4. Electrical Thermometers for Aircraft

    NASA Technical Reports Server (NTRS)

    Peterson, John B; Womack, S H J

    1937-01-01

    Electrical thermometers commonly used on aircraft are the thermoelectric type for measuring engine-cylinder temperatures, the resistance type for measuring air temperatures, and the superheat meters of thermoelectric and resistance types for use on airships. These instruments are described and their advantages and disadvantages enumerated. Methods of testing these instruments and the performance to be expected from each are discussed. The field testing of engine-cylinder thermometers is treated in detail.

  5. Slotted Aircraft Wing

    NASA Technical Reports Server (NTRS)

    McLean, James D. (Inventor); Witkowski, David P. (Inventor); Campbell, Richard L. (Inventor)

    2006-01-01

    A swept aircraft wing includes a leading airfoil element and a trailing airfoil element. At least one full-span slot is defined by the wing during at least one transonic condition of the wing. The full-span slot allows a portion of the air flowing along the lower surface of the leading airfoil element to split and flow over the upper surface of the trailing airfoil element so as to achieve a performance improvement in the transonic condition.

  6. Comparing coal handling system costs

    SciTech Connect

    Lehto, J.M.

    1996-03-01

    Good maintenance practices and proactive planning are essential to ensure coal handling equipment performance, but a look at the entire cost of handling coal has yielded some surprising conclusions. Optimizing a given system can be challenging and requires a close analysis of the total cost. This article addresses the cost analysis of the coal handling system at the Northern States Power Co. (NSP) Sherburne County Plant (Sherco); the largest coal-fired plant in Minnesota. Sherco consists of two Combustion Engineering 750-MW tangentially fired boilers and one 850-MW Babcock and Wilcox wall-fired unit. The two 750-MW units are fitted with wet limestone scrubbers to control both particulates and sulfur. The 850-MW unit, on the other hand, is connected to a Joy Niro dry scrubber and baghouse. All of the coal consumed by Sherco is sub-bituminous Powder River Basin Coal from Montana and Wyoming. The coal is purchased from half a dozen mines including Westmoreland, Colestrip, Black Thunder, Antelope and Rochelle. Although quite similar in heating value and moisture content, these coals differ markedly in ash content, sulfur content, dustiness and spontaneous heating characteristics.

  7. The Role of Clear Sky Identification in the Study of Cloud Radiative Effects: Combine Analysis from ISCCP and the Scanner of Radiation Budget (ScaRaB)

    NASA Technical Reports Server (NTRS)

    Rossow, W. B.; Stubenrauch, C. J.; Briand, V.; Hansen, James E. (Technical Monitor)

    2001-01-01

    Since the effect of clouds on the earth's radiation balance is often estimated as the difference of net radiative fluxes at the top of the atmosphere between all situations and monthly averaged clear sky situations of the same regions, a reliable identification of clear sky is important for the study of cloud radiative effects. The Scanner for Radiation Balance (ScaRaB) radiometer on board the Russian Meteor-3/7 satellite provided earth radiation budget observations from March 1994 to February 1995 with two ERBE-Re broad-band longwave and shortwave channels. Two narrow-band channels, in the infrared atmospheric window and in the visible band, have been added to the ScaRaB instrument to improve the cloud scene identification. The International Satellite Cloud Climatology Project (ISCCP) method for cloud detection and determination of cloud and surface properties uses the same narrow-band channels as ScaRaB, but is employed to a collection of measurements at a better spatial resolution of about 5 km. By applying the original ISCCP algorithms to the ScaRaB data, the clear sky frequency is about 5% lower than the one over quasi-simultaneous original ISCCP data, an indication that the ISCCP cloud detection is quite stable. However, one would expect an about 10 to 20% smaller clear sky occurrence over the larger ScaRaB pixels. Adapting the ISCCP algorithms to the reduced spatial resolution of 60 km and to the different time sampling of the ScaRaB data leads therefore to a reduction of a residual cloud contamination. A sensitivity study with time-space collocated ScaRaB and original ISCCP data at a spatial resolution of 1deg longitude x 1deg latitude shows that the effect of clear sky identification method plays a higher role on the clear sky frequency and therefore on the statistics than on the zonal mean values of the clear sky fluxes. Nevertheless, the zonal outgoing longwave fluxes corresponding to ERBE clear sky are in general about 2 to 10 W/sq m higher than those

  8. Feedback control laws for highly maneuverable aircraft

    NASA Technical Reports Server (NTRS)

    Garrard, William L.; Balas, Gary J.

    1992-01-01

    The results of a study of the application of H infinity and mu synthesis techniques to the design of feedback control laws for the longitudinal dynamics of the High Angle of Attack Research Vehicle (HARV) are presented. The objective of this study is to develop methods for the design of feedback control laws which cause the closed loop longitudinal dynamics of the HARV to meet handling quality specifications over the entire flight envelope. Control law designs are based on models of the HARV linearized at various flight conditions. The control laws are evaluated by both linear and nonlinear simulations of typical maneuvers. The fixed gain control laws resulting from both the H infinity and mu synthesis techniques result in excellent performance even when the aircraft performs maneuvers in which the system states vary significantly from their equilibrium design values. Both the H infinity and mu synthesis control laws result in performance which compares favorably with an existing baseline longitudinal control law.

  9. Handling Qualities Results of an Initial Geared Flap Tilt Wing Piloted Simulation

    NASA Technical Reports Server (NTRS)

    Guerrero, Lourdes M.; Corliss, Lloyd D.

    1991-01-01

    An exploratory simulation study of a novel approach to pitch control for a tilt wing aircraft was conducted in 1990 on the NASA-Ames Vertical Motion Simulator. The purpose of the study was to evaluate and compare the handling qualities of both a conventional and a geared flap tilt wing control configuration. The geared flap is an innovative control concept which has the potential for reducing or eliminating the horizontal pitch control tail rotor or reaction jets required by prior tilt wing designs. The handling qualities results of the geared flap control configuration are presented in this paper and compared to the conventional (programmed flap) tilt wing control configuration. This paper also describes the geared flap concept, the tilt wing aircraft, the simulation model, the simulation facility and experiment setup, and the pilot evaluation tasks and procedures.

  10. Shuttle in Mate-Demate Device being Loaded onto SCA-747 - Rear View

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Evening light begins to fade at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, as technicians begin the task of mounting the Space Shuttle Atlantis atop NASA's 747 Shuttle Carrier Aircraft (NASA 911) for the ferry flight back to the Kennedy Space Center, Fla., following its STS-44 flight 24 November-1 December 1991. Post-flight servicing of the orbiters, and the mating operation is carried out at Dryden at the Mate-Demate Device, the large gantry-like structure that hoists the spacecraft to various levels during post-spaceflight processing and attachment to the 747. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle

  11. Shuttle in Mate-Demate Device being Loaded onto SCA-747 - Side View

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Evening light begins to fade at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, as technicians begin the task of mounting the Space Shuttle Atlantis atop NASA's 747 Shuttle Carrier Aircraft (NASA #911) for the ferry flight back to the Kennedy Space Center, Fla., following its STS-44 flight 24 November-1 December 1991. Post-flight servicing of the orbiters, and the mating operation, is carried out at Dryden at the Mate-Demate Device (MDD), the large gantry-like structure that hoists the spacecraft to various levels during post-space flight processing and attachment to the 747. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space

  12. Shuttle in Mate-Demate Device being Loaded onto SCA-747

    NASA Technical Reports Server (NTRS)

    1991-01-01

    At NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, technicians begin the task of mounting the Space Shuttle Atlantis atop NASA's 747 Shuttle Carrier Aircraft (NASA #911) for the ferry flight back to the Kennedy Space Center, Florida, following its STS-44 flight 24 November - 1 December 1991. Post-flight servicing of the orbiters, and the mating operation, is carried out at Dryden at the Mate-Demate Device (MDD), the large gantry-like structure that hoists the spacecraft to various levels during post-space flight processing and attachment to the 747. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and

  13. Shuttle Endeavour Mated to 747 SCA Takeoff for Delivery to Kennedy Space Center, Florida

    NASA Technical Reports Server (NTRS)

    1991-01-01

    NASA's 747 Shuttle Carrier Aircraft No. 911, with the space shuttle orbiter Endeavour securely mounted atop its fuselage, begins the ferry flight from Rockwell's Plant 42 at Palmdale, California, where the orbiter was built, to the Kennedy Space Center, Florida. At Kennedy, the space vehicle was processed and launched on orbital mission STS-49, which landed at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, 16 May 1992. NASA 911, the second modified 747 that went into service in November 1990, has special support struts atop the fuselage and internal strengthening to accommodate the added weight of the orbiters. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission

  14. Shuttle Endeavour Mated to 747 SCA Taxi to Runway for Delivery to Kennedy Space Center, Florida

    NASA Technical Reports Server (NTRS)

    1991-01-01

    NASA's 747 Shuttle Carrier Aircraft No. 911, with the space shuttle orbiter Endeavour securely mounted atop its fuselage, taxies to the runway to begin the ferry flight from Rockwell's Plant 42 at Palmdale, California, where the orbiter was built, to the Kennedy Space Center, Florida. At Kennedy, the space vehicle was processed and launched on orbital mission STS-49, which landed at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, 16 May 1992. NASA 911, the second modified 747 that went into service in November 1990, has special support struts atop the fuselage and internal strengthening to accommodate the added weight of the orbiters. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay

  15. STS-68 on Runway with 747 SCA/Columbia Ferry Flyby

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The space shuttle Endeavour receives a high-flying salute from its sister shuttle, Columbia, atop NASA's Shuttle Carrier Aircraft, shortly after Endeavor's landing 12 October 1994, at Edwards, California, to complete mission STS-68. Columbia was being ferried from the Kennedy Space Center, Florida, to Air Force Plant 42, Palmdale, California, where it will undergo six months of inspections, modifications, and systems upgrades. The STS-68 11-day mission was devoted to radar imaging of Earth's geological features with the Space Radar Laboratory. The orbiter is surrounded by equipment and personnel that make up the ground support convoy that services the space vehicles as soon as they land. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the

  16. STS-49 Shuttle Endevour in Mate-Demate Device being Loaded onto SCA-747 - Front View

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Space Shuttle Endeavour being loaded onto NASA's Shuttle Carrier Aircraft in the Mate-Demate Device (MDD) at the Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, shortly before being ferried back to the Kennedy Space Center, Florida. Endeavour landed at 1:57 p.m. (PDT) 16 May 1992, marking the completion of the new orbiter's first mission in space during which the crew of seven rendevoused with the Intelsat VI satellite, attached a booster motor, and redeployed it into a high geosynchronous orbit. Endeavour and its crew was launched on a planned 7-day mission 7 May 1992, but the landing was delayed two days to allow extra time to rescue Intelsat and complete space station assembly techniques originally planned. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific

  17. Orion Entry Handling Qualities Assessments

    NASA Technical Reports Server (NTRS)

    Bihari, B.; Tiggers, M.; Strahan, A.; Gonzalez, R.; Sullivan, K.; Stephens, J. P.; Hart, J.; Law, H., III; Bilimoria, K.; Bailey, R.

    2011-01-01

    The Orion Command Module (CM) is a capsule designed to bring crew back from the International Space Station (ISS), the moon and beyond. The atmospheric entry portion of the flight is deigned to be flown in autopilot mode for nominal situations. However, there exists the possibility for the crew to take over manual control in off-nominal situations. In these instances, the spacecraft must meet specific handling qualities criteria. To address these criteria two separate assessments of the Orion CM s entry Handling Qualities (HQ) were conducted at NASA s Johnson Space Center (JSC) using the Cooper-Harper scale (Cooper & Harper, 1969). These assessments were conducted in the summers of 2008 and 2010 using the Advanced NASA Technology Architecture for Exploration Studies (ANTARES) six degree of freedom, high fidelity Guidance, Navigation, and Control (GN&C) simulation. This paper will address the specifics of the handling qualities criteria, the vehicle configuration, the scenarios flown, the simulation background and setup, crew interfaces and displays, piloting techniques, ratings and crew comments, pre- and post-fight briefings, lessons learned and changes made to improve the overall system performance. The data collection tools, methods, data reduction and output reports will also be discussed. The objective of the 2008 entry HQ assessment was to evaluate the handling qualities of the CM during a lunar skip return. A lunar skip entry case was selected because it was considered the most demanding of all bank control scenarios. Even though skip entry is not planned to be flown manually, it was hypothesized that if a pilot could fly the harder skip entry case, then they could also fly a simpler loads managed or ballistic (constant bank rate command) entry scenario. In addition, with the evaluation set-up of multiple tasks within the entry case, handling qualities ratings collected in the evaluation could be used to assess other scenarios such as the constant bank angle

  18. Handling qualities of the High Speed Civil Transport

    NASA Technical Reports Server (NTRS)

    Solies, U. Peter

    1994-01-01

    The low speed handling qualities of a High Speed Civil Transport class aircraft have been investigated by using data of the former Advanced Supersonic Transport (AST) 105. The operation of such vehicles in the airport terminal area is characterized by 'backside' performance. Main objectives of this research effort were: (Q) determination of the nature and magnitude of the speed instability associated with the backside of the thrust required curve; (2) confirmation of the validity of existing MIL-SPEC handling qualities criteria; (3) safety of operation of the vehicle in the event of autothrottle failure; and (4) correlation of required engine responsiveness with level of speed instability. Preliminary findings comprise the following: (1) The critical velocity for speed instability was determined to be 196 knots, well above the projected approach speed of 155 knots. This puts the vehicle far on the backside of its thrust required curve. While the aircraft can be configured to have static and dynamic stability at this trim point, a significant speed instability emerges, if a pilot or autopilot attempts flight path control with elevator and/or canard control surfaces only. This requires a properly configured autothrottle and/or variable aerodynamic drag devices which can provide speed stability; (2) An AST 105 type vehicle meets MIL-SPEC criteria only in part. While the damping criteria for phugoid and short period motion are met easily, the AST 105 falls short of the required minimum short period frequency, meaning that the HSCT is too sluggish in pitch to meet the military criteria. Obviously the military specification do not consider a vehicle with such high pitch inertia. With regard to speed stability and flight path stability criteria, the vehicle meets levels 2 and 3 of the military requirements, indicating that it would be landed safety with manual controls in case of an autothrottle failure, even though the pilot workload would be high; and (3) This requires

  19. Interaction of Aircraft Wakes From Laterally Spaced Aircraft

    NASA Technical Reports Server (NTRS)

    Proctor, Fred H.

    2009-01-01

    Large Eddy Simulations are used to examine wake interactions from aircraft on closely spaced parallel paths. Two sets of experiments are conducted, with the first set examining wake interactions out of ground effect (OGE) and the second set for in ground effect (IGE). The initial wake field for each aircraft represents a rolled-up wake vortex pair generated by a B-747. Parametric sets include wake interactions from aircraft pairs with lateral separations of 400, 500, 600, and 750 ft. The simulation of a wake from a single aircraft is used as baseline. The study shows that wake vortices from either a pair or a formation of B-747 s that fly with very close lateral spacing, last longer than those from an isolated B-747. For OGE, the inner vortices between the pair of aircraft, ascend, link and quickly dissipate, leaving the outer vortices to decay and descend slowly. For the IGE scenario, the inner vortices ascend and last longer, while the outer vortices decay from ground interaction at a rate similar to that expected from an isolated aircraft. Both OGE and IGE scenarios produce longer-lasting wakes for aircraft with separations less than 600 ft. The results are significant because concepts to increase airport capacity have been proposed that assume either aircraft formations and/or aircraft pairs landing on very closely spaced runways.

  20. Developing a workstation-based, real-time simulation for rapid handling qualities evaluations during design

    NASA Technical Reports Server (NTRS)

    Anderson, Frederick; Biezad, Daniel J.

    1994-01-01

    This paper describes the Rapid Aircraft DynamIcs AssessmeNt (RADIAN) project - an integration of the Aircraft SYNThesis (ACSTNT) design code with the USAD DATCOM code that estimates stability derivatives. Both of these codes are available to universities. These programs are then linked to flight simulation and flight controller synthesis tools and resulting design is evaluated on a graphics workstation. The entire process reduces the preliminary design time by an order of magnitude and provides an initial handling qualities evaluation of the design coupled to a control law. The integrated design process is applicable to both conventional aircraft taken from current textbooks and to unconventional designs emphasizing agility and propulsive control of attitude. The interactive and concurrent nature of the design process has been well received by industry and by design engineers at NASA. The process is being implemented into the design curriculum and is being used by students who view it as a significant advance over prior methods.

  1. Mission management aircraft operations manual

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This manual prescribes the NASA mission management aircraft program and provides policies and criteria for the safe and economical operation, maintenance, and inspection of NASA mission management aircraft. The operation of NASA mission management aircraft is based on the concept that safety has the highest priority. Operations involving unwarranted risks will not be tolerated. NASA mission management aircraft will be designated by the Associate Administrator for Management Systems and Facilities. NASA mission management aircraft are public aircraft as defined by the Federal Aviation Act of 1958. Maintenance standards, as a minimum, will meet those required for retention of Federal Aviation Administration (FAA) airworthiness certification. Federal Aviation Regulation Part 91, Subparts A and B, will apply except when requirements of this manual are more restrictive.

  2. 14 CFR 43.7 - Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., airframes, aircraft engines, propellers, appliances, or component parts for return to service after... FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE, REBUILDING, AND ALTERATION § 43.7 Persons authorized to approve aircraft, airframes, aircraft...

  3. Determination of Top-of-Atmosphere Longwave Radiative Fluxes: A Comparison Between Two Approaches Using ScaRaB Data

    NASA Technical Reports Server (NTRS)

    Chen, Ting; Rossow, William B.; Hansen, James E. (Technical Monitor)

    2001-01-01

    Two conceptually different approaches (broadband-based ERBE and narrowband-based ISCCP approaches), used to derive the TOA longwave radiative fluxes, are compared using the ScaRaB simultaneous narrowband and broadband measurements. This study directly shows that the ERBE MLE-derived cloud covers implicitly contain some information on the cloud optical properties. A spurious view-zenith-angle dependence of the MLE scene identification scheme is confirmed by this study. Except for very thin cirrus clouds, differences between the ERBE and ISCCP approaches are in general < 10 W/sq m for the TOA LW radiative fluxes. For clear pixels, the model calculated (ISCCP approach) TOA LW radiances are systematically smaller than the observations. Though the bias is found to be correlated on the column precipitable water amount, the exact source of this discrepancy remains undetermined and merits further study. Compared with the radiative transfer model used in this study, the ERBE LW ADMs are too weakly limb-darkened for optically thin clouds, but too strongly limb-darkened for optically thick clouds, indicating that more accurate instantaneous TOA LW flux estimations from the ERBE approach would require additional cloud classes based on cloud height and optical thickness.

  4. A unique facility for V/STOL aircraft hover testing. [Langley Impact Dynamics Research Facility

    NASA Technical Reports Server (NTRS)

    Culpepper, R. G.; Murphy, R. D.; Gillespie, E. A.; Lane, A. G.

    1979-01-01

    The Langley Impact Dynamics Research Facility (IDRF) was modified to obtain static force and moment data and to allow assessment of aircraft handling qualities during dynamic tethered hover flight. Test probe procedures were also established. Static lift and control measurements obtained are presented along with results of limited dynamic tethered hover flight.

  5. Effects of simulator motion and visual characteristics on rotorcraft handling qualities evaluations

    NASA Technical Reports Server (NTRS)

    Mitchell, David G.; Hart, Daniel C.

    1993-01-01

    The pilot's perceptions of aircraft handling qualities are influenced by a combination of the aircraft dynamics, the task, and the environment under which the evaluation is performed. When the evaluation is performed in a groundbased simulator, the characteristics of the simulation facility also come into play. Two studies were conducted on NASA Ames Research Center's Vertical Motion Simulator to determine the effects of simulator characteristics on perceived handling qualities. Most evaluations were conducted with a baseline set of rotorcraft dynamics, using a simple transfer-function model of an uncoupled helicopter, under different conditions of visual time delays and motion command washout filters. Differences in pilot opinion were found as the visual and motion parameters were changed, reflecting a change in the pilots' perceptions of handling qualities, rather than changes in the aircraft model itself. The results indicate a need for tailoring the motion washout dynamics to suit the task. Visual-delay data are inconclusive but suggest that it may be better to allow some time delay in the visual path to minimize the mismatch between visual and motion, rather than eliminate the visual delay entirely through lead compensation.

  6. Aircraft cockpit vision: Math model

    NASA Technical Reports Server (NTRS)

    Bashir, J.; Singh, R. P.

    1975-01-01

    A mathematical model was developed to describe the field of vision of a pilot seated in an aircraft. Given the position and orientation of the aircraft, along with the geometrical configuration of its windows, and the location of an object, the model determines whether the object would be within the pilot's external vision envelope provided by the aircraft's windows. The computer program using this model was implemented and is described.

  7. The relationship between manual handling performance and recent flying experience in air transport pilots.

    PubMed

    Ebbatson, Matt; Harris, Don; Huddlestone, John; Sears, Rodney

    2010-02-01

    Modern jet transport aircraft are typically flown using the on-board automation by the pilot programming commands into the auto-flight systems. Anecdotal evidence exists suggesting that pilots of highly automated aircraft experience manual flying skills decay as a result of a lack of opportunity to practise hand-flying during line operations. The ability of a pilot to revert to basic manual control is essential, for example, in cases where the aircraft's automatic capability is diminished or when reconfiguring the automatics is an ineffective use of crew capacity. However, there is a paucity of objective data to substantiate this perceived threat to flight safety. Furthermore, traditional performance measurement techniques may lack the ability to identify subtle but significant differences in pilots' manual handling ability in large transport aircraft. This study examines the relationship between pilot manual handling performance and their recent flying experience using both traditional flight path tracking measures and frequency-based control strategy measures. Significant relationships are identified between pilots' very recent flying experience and their manual control strategy. Statement of Relevance: The study demonstrates a novel application of frequency analysis, which produces a broader and more sensitive analysis of pilot performance than has been offered in previous research. Additionally, the relationships that are found to exist between recent flying experience and manual flying performance will help to guide future pilot assessment and training. PMID:20099179

  8. 19 CFR 122.64 - Other aircraft.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Other aircraft. 122.64 Section 122.64 Customs... AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.64 Other aircraft. Clearance or permission to depart shall be requested by the aircraft commander or agent for aircraft...

  9. 40 CFR 87.6 - Aircraft safety.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Aircraft safety. 87.6 Section 87.6... POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES General Provisions § 87.6 Aircraft safety. The provisions of... be met within the specified time without creating a hazard to aircraft safety....

  10. 19 CFR 122.64 - Other aircraft.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Other aircraft. 122.64 Section 122.64 Customs... AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.64 Other aircraft. Clearance or permission to depart shall be requested by the aircraft commander or agent for aircraft...

  11. 40 CFR 87.6 - Aircraft safety.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Aircraft safety. 87.6 Section 87.6... POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES General Provisions § 87.6 Aircraft safety. The provisions of... be met within the specified time without creating a hazard to aircraft safety....

  12. 19 CFR 122.64 - Other aircraft.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Other aircraft. 122.64 Section 122.64 Customs... AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.64 Other aircraft. Clearance or permission to depart shall be requested by the aircraft commander or agent for aircraft...

  13. 19 CFR 122.64 - Other aircraft.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Other aircraft. 122.64 Section 122.64 Customs... AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.64 Other aircraft. Clearance or permission to depart shall be requested by the aircraft commander or agent for aircraft...

  14. 7 CFR 1205.312 - Handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions § 1205.312 Handle. Handle means to harvest, gin, warehouse, compress, purchase, market, transport, or otherwise acquire ownership or control of cotton....

  15. 7 CFR 1205.312 - Handle.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions § 1205.312 Handle. Handle means to harvest, gin, warehouse, compress, purchase, market, transport, or otherwise acquire ownership or control of cotton....

  16. The Typical General Aviation Aircraft

    NASA Technical Reports Server (NTRS)

    Turnbull, Andrew

    1999-01-01

    The reliability of General Aviation aircraft is unknown. In order to "assist the development of future GA reliability and safety requirements", a reliability study needs to be performed. Before any studies on General Aviation aircraft reliability begins, a definition of a typical aircraft that encompasses most of the general aviation characteristics needs to be defined. In this report, not only is the typical general aviation aircraft defined for the purpose of the follow-on reliability study, but it is also separated, or "sifted" into several different categories where individual analysis can be performed on the reasonably independent systems. In this study, the typical General Aviation aircraft is a four-place, single engine piston, all aluminum fixed-wing certified aircraft with a fixed tricycle landing gear and a cable operated flight control system. The system breakdown of a GA aircraft "sifts" the aircraft systems and components into five categories: Powerplant, Airframe, Aircraft Control Systems, Cockpit Instrumentation Systems, and the Electrical Systems. This breakdown was performed along the lines of a failure of the system. Any component that caused a system to fail was considered a part of that system.

  17. Intelligent aircraft/airspace systems

    NASA Technical Reports Server (NTRS)

    Wangermann, John P.

    1995-01-01

    Projections of future air traffic predict at least a doubling of the number of revenue passenger miles flown by the year 2025. To meet this demand, an Intelligent Aircraft/Airspace System (IAAS) has been proposed. The IAAS operates on the basis of principled negotiation between intelligent agents. The aircraft/airspace system today consists of many agents, such as airlines, control facilities, and aircraft. All the agents are becoming increasingly capable as technology develops. These capabilities should be exploited to create an Intelligent Aircraft/Airspace System (IAAS) that would meet the predicted traffic levels of 2005.

  18. Scheduling of an aircraft fleet

    NASA Technical Reports Server (NTRS)

    Paltrinieri, Massimo; Momigliano, Alberto; Torquati, Franco

    1992-01-01

    Scheduling is the task of assigning resources to operations. When the resources are mobile vehicles, they describe routes through the served stations. To emphasize such aspect, this problem is usually referred to as the routing problem. In particular, if vehicles are aircraft and stations are airports, the problem is known as aircraft routing. This paper describes the solution to such a problem developed in OMAR (Operative Management of Aircraft Routing), a system implemented by Bull HN for Alitalia. In our approach, aircraft routing is viewed as a Constraint Satisfaction Problem. The solving strategy combines network consistency and tree search techniques.

  19. NASA research in aircraft propulsion

    NASA Technical Reports Server (NTRS)

    Beheim, M. A.

    1982-01-01

    A broad overview of the scope of research presently being supported by NASA in aircraft propulsion is presented with emphasis on Lewis Research Center activities related to civil air transports, CTOL and V/STOL systems. Aircraft systems work is performed to identify the requirements for the propulsion system that enhance the mission capabilities of the aircraft. This important source of innovation and creativity drives the direction of propulsion research. In a companion effort, component research of a generic nature is performed to provide a better basis for design and provides an evolutionary process for technological growth that increases the capabilities of all types of aircraft. Both are important.

  20. Zero g manual cargo handling

    NASA Technical Reports Server (NTRS)

    Spady, A. A., Jr.; Beasley, G. P.

    1972-01-01

    A series of studies were conducted utilizing a water-immersion simulator facility to better define the cargo that can realistically be handled by man. The initial phase of the program was a parametric study to define man's intravehicular (IV) cargo transfer capabilities, and its results are reported. Additional phases of the study, deal with: (1) man's ability to perform extravehicular (EV) cargo transfer, (2) the ability to transfer cargo through a 1.5 m (5-foot) diameter tunnel (IV), and (3) the utilization of electroadhesive/electromagnetic mobility aids for both IV and EV self-locomotion and cargo transfer.

  1. Design of a flight control system for a highly maneuverable aircraft using mu synthesis

    NASA Technical Reports Server (NTRS)

    Reiner, Jacob; Balas, Gary J.; Garrard, William L.

    1993-01-01

    This paper presents a methodology for the design of longitudinal controllers for high performance aircraft operating over large ranges of angle of attack. The technique used for controller design is structured singular value or mu synthesis. The controller is designed to minimize the weighted H-infinity norm of the error between the aircraft response and the desired handling quality specifications without saturating the control actuators. The mu synthesis procedure ensures that the stability and performance of the aircraft is robust to parameter variations and modeling uncertainties included in the design model. Nonlinear simulations demonstrate that the controller satisfies handling quality requirements and provides excellent tracking of pilot inputs over a wide range of transient angles of attack and Mach number.

  2. 7 CFR 932.16 - Handle.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 932.16 Handle. Handle means to: (a) Size-grade olives, (b) process olives, or (c) use processed olives in the production of packaged olives, within the production area, or (d)...

  3. 7 CFR 932.16 - Handle.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 932.16 Handle. Handle means to: (a) Size-grade olives, (b) process olives, or (c) use processed olives in the production of packaged olives, within the production area, or (d)...

  4. 7 CFR 932.16 - Handle.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 932.16 Handle. Handle means to: (a) Size-grade olives, (b) process olives, or (c) use processed olives in the production of packaged olives, within the production area, or (d)...

  5. 7 CFR 985.8 - Handle.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... SPEARMINT OIL PRODUCED IN THE FAR WEST Order Regulating Handling Definitions § 985.8 Handle. Handle means to prepare oil for market, acquire oil from a producer, use oil commercially of own production, or sell, transport, or ship (except as a common or contract carrier of oil owned by another), or otherwise place...

  6. 7 CFR 985.8 - Handle.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... SPEARMINT OIL PRODUCED IN THE FAR WEST Order Regulating Handling Definitions § 985.8 Handle. Handle means to prepare oil for market, acquire oil from a producer, use oil commercially of own production, or sell, transport, or ship (except as a common or contract carrier of oil owned by another), or otherwise place...

  7. 7 CFR 985.8 - Handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... SPEARMINT OIL PRODUCED IN THE FAR WEST Order Regulating Handling Definitions § 985.8 Handle. Handle means to prepare oil for market, acquire oil from a producer, use oil commercially of own production, or sell, transport, or ship (except as a common or contract carrier of oil owned by another), or otherwise place...

  8. 7 CFR 985.8 - Handle.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... SPEARMINT OIL PRODUCED IN THE FAR WEST Order Regulating Handling Definitions § 985.8 Handle. Handle means to prepare oil for market, acquire oil from a producer, use oil commercially of own production, or sell, transport, or ship (except as a common or contract carrier of oil owned by another), or otherwise place...

  9. 7 CFR 985.8 - Handle.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SPEARMINT OIL PRODUCED IN THE FAR WEST Order Regulating Handling Definitions § 985.8 Handle. Handle means to prepare oil for market, acquire oil from a producer, use oil commercially of own production, or sell, transport, or ship (except as a common or contract carrier of oil owned by another), or otherwise place...

  10. 7 CFR 981.16 - To handle.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.16 To handle. To handle means to use almonds commercially of own production or to sell, consign, transport, ship (except as a common carrier of almonds owned by another)...

  11. 7 CFR 981.16 - To handle.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.16 To handle. To handle means to use almonds commercially of own production or to sell, consign, transport, ship (except as a common carrier of almonds owned by another)...

  12. 7 CFR 981.16 - To handle.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.16 To handle. To handle means to use almonds commercially of own production or to sell, consign, transport, ship (except as a common carrier of almonds owned by another)...

  13. 7 CFR 981.16 - To handle.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.16 To handle. To handle means to use almonds commercially of own production or to sell, consign, transport, ship (except as a common carrier of almonds owned by another)...

  14. 7 CFR 981.16 - To handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.16 To handle. To handle means to use almonds commercially of own production or to sell, consign, transport, ship (except as a common carrier of almonds owned by another)...

  15. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Manufacture of new aircraft, aircraft... Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b) and (c) of this section, no person may manufacture a new aircraft, aircraft engine, or propeller based...

  16. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Manufacture of new aircraft, aircraft... Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b) and (c) of this section, no person may manufacture a new aircraft, aircraft engine, or propeller based...

  17. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Manufacture of new aircraft, aircraft... Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b) and (c) of this section, no person may manufacture a new aircraft, aircraft engine, or propeller based...

  18. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Manufacture of new aircraft, aircraft... Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b) and (c) of this section, no person may manufacture a new aircraft, aircraft engine, or propeller based...

  19. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Manufacture of new aircraft, aircraft... Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b) and (c) of this section, no person may manufacture a new aircraft, aircraft engine, or propeller based...

  20. Aircraft surface coatings

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A series of studies in which films and liquid spray-on materials were evaluated in the laboratory for transport aircraft external surface coatings are summarized. Elastomeric polyurethanes were found to best meet requirements. Two commercially available products, CAAPCO B-274 and Chemglaze M313, were subjected to further laboratory testing, airline service evaluations, and drag-measurement flight tests. It was found that these coatings were compatible with the severe operating environment of airlines and that coatings reduced airplane drag. An economic analysis indicated significant dollar benefits to airlines from application of the coatings.

  1. Aircraft Speed Instruments

    NASA Technical Reports Server (NTRS)

    Beij, K Hilding

    1933-01-01

    This report presents a concise survey of the measurement of air speed and ground speed on board aircraft. Special attention is paid to the pitot-static air-speed meter which is the standard in the United States for airplanes. Air-speed meters of the rotating vane type are also discussed in considerable detail on account of their value as flight test instruments and as service instruments for airships. Methods of ground-speed measurement are treated briefly, with reference to the more important instruments. A bibliography on air-speed measurement concludes the report.

  2. Structural integrity in aircraft.

    NASA Technical Reports Server (NTRS)

    Hardrath, H. F.

    1973-01-01

    The paper reviews briefly the current design philosophies for achieving long, efficient, and reliable service in aircraft structures. The strengths and weaknesses of these design philosophies and their demonstrated records of success are discussed. The state of the art has not been developed to the point where designing can be done without major test inspection and maintenance programs. A broad program of research is proposed through which a viable computerized design scheme will be provided during the next decade. The program will organize and correlate existing knowledge on fatigue and fracture behavior, identify gaps in this knowledge, and guide specific research to upgrade design capabilities.

  3. Hydrogen aircraft technology

    NASA Technical Reports Server (NTRS)

    Brewer, G. D.

    1991-01-01

    A comprehensive evaluation is conducted of the technology development status, economics, commercial feasibility, and infrastructural requirements of LH2-fueled aircraft, with additional consideration of hydrogen production, liquefaction, and cryostorage methods. Attention is given to the effects of LH2 fuel cryotank accommodation on the configurations of prospective commercial transports and military airlifters, SSTs, and HSTs, as well as to the use of the plentiful heatsink capacity of LH2 for innovative propulsion cycles' performance maximization. State-of-the-art materials and structural design principles for integral cryotank implementation are noted, as are airport requirements and safety and environmental considerations.

  4. Slotted Aircraft Wing

    NASA Technical Reports Server (NTRS)

    Vassberg, John C. (Inventor); Gea, Lie-Mine (Inventor); McLean, James D. (Inventor); Witowski, David P. (Inventor); Krist, Steven E. (Inventor); Campbell, Richard L. (Inventor)

    2006-01-01

    An aircraft wing includes a leading airfoil element and a trailing airfoil element. At least one slot is defined by the wing during at least one transonic condition of the wing. The slot may either extend spanwise along only a portion of the wingspan, or it may extend spanwise along the entire wingspan. In either case, the slot allows a portion of the air flowing along the lower surface of the leading airfoil element to split and flow over the upper surface of the trailing airfoil element so as to achieve a performance improvement in the transonic condition.

  5. XV-15 Tiltrotor Aircraft: 1997 Acoustic Testing

    NASA Technical Reports Server (NTRS)

    Edwards, Bryan D.; Conner, David A.

    2003-01-01

    XV-15 acoustic test is discussed, and measured results are presented. The test was conducted by NASA Langley and Bell Helicopter Textron, Inc., during June - July 1997, at the BHTI test site near Waxahachie, Texas. This was the second in a series of three XV-15 tests to document the acoustic signature of the XV-15 tiltrotor aircraft for a variety of flight conditions and minimize the noise signature during approach. Tradeoffs between flight procedures and the measured noise are presented to illustrate the noise abatement flight procedures. The test objectives were to: (1) support operation of future tiltrotors by further developing and demonstrating low-noise flight profiles, while maintaining acceptable handling and ride qualities, and (2) refine approach profiles, selected from previous (1995) tiltrotor testing, to incorporate Instrument Flight Rules (IFR), handling qualities constraints, operations and tradeoffs with sound. Primary emphasis was given to the approach flight conditions where blade-vortex interaction (BVI) noise dominates, because this condition influences community noise impact more than any other. An understanding of this part of the noise generating process could guide the development of low noise flight operations and increase the tiltrotor's acceptance in the community.

  6. Aircraft Inspection for the General Aviation Aircraft Owner.

    ERIC Educational Resources Information Center

    Federal Aviation Administration (DOT), Washington, DC. Flight Standards Service.

    Presented is useful information for owners, pilots, student mechanics, and others with aviation interests. Part I of this booklet outlines aircraft inspection requirements, owner responsibilities, inspection time intervals, and sources of basic information. Part II is concerned with the general techniques used to inspect an aircraft. (Author/JN)

  7. Remote Handling System for Ignitor^*

    NASA Astrophysics Data System (ADS)

    Galbiati, L.; Bianchi, A.; Lucca, F.; Coppi, B.

    2005-10-01

    Since access in Ignitor is through the limited width of the equatorial ports, the use of remote handling (RH) technology for any in-vessel intervention is required, even before the vessel becomes activated. In particular, the first wall of Ignitor, which is made of TZM (Molybdenum) tiles mounted on Inconel tile-carriers covering the entire plasma chamber, has been designed to be installed and replaced entirely by the RH system. The presence of radiation screens inside the cryostat and around the ports ensure a sufficiently low level of activation around the machine to avoid the need of ex-vessel RH techniques. The in-vessel RH system is based on two transporters carrying an articulated boom with end-effectors, supported by a movable structure over a transport system that can be lifted and set in position adjacent to two opposite horizontal ports. The design of the in-vessel RH system, of the boom and its enclosure, and of the most significant end-effectors (welding and cutting tools, and tools for the removal and handling of tile carriers) has been completed. A series of other dedicated tools for installation and maintainances of diagnostics components, of the RF antennas, vacuum cleaners, tools for general inspection and metrology are included in the design. ^*Sponsored in part by ENEA of Italy and by the U.S. DOE.

  8. SCaMC-1 promotes cancer cell survival by desensitizing mitochondrial permeability transition via ATP/ADP-mediated matrix Ca2+ buffering

    PubMed Central

    Traba, J; del Arco, A; Duchen, M R; Szabadkai, G; Satrústegui, J

    2012-01-01

    Ca2+-mediated mitochondrial permeability transition (mPT) is the final common pathway of stress-induced cell death in many major pathologies, but its regulation in intact cells is poorly understood. Here we report that the mitochondrial carrier SCaMC-1/SLC25A24 mediates ATP-Mg2−/Pi2− and/or HADP2−/Pi2− uptake into the mitochondria after an increase in cytosolic [Ca2+]. ATP and ADP contribute to Ca2+ buffering in the mitochondrial matrix, resulting in desensitization of the mPT. Comprehensive gene expression analysis showed that SCaMC-1 overexpression is a general feature of transformed and cancer cells. Knockdown of the transporter led to vast reduction of mitochondrial Ca2+ buffering capacity and sensitized cells to mPT-mediated necrotic death triggered by oxidative stress and Ca2+ overload. These findings revealed that SCaMC-1 exerts a negative feedback control between cellular Ca2+ overload and mPT-dependent cell death, suggesting that the carrier might represent a novel target for cancer therapy. PMID:22015608

  9. Dumbo heavy lifter aircraft

    NASA Technical Reports Server (NTRS)

    Riester, Peter; Ellis, Colleen; Wagner, Michael; Orren, Scott; Smith, Byron; Skelly, Michael; Zgraggen, Craig; Webber, Matt

    1992-01-01

    The world is rapidly changing from one with two military superpowers, with which most countries were aligned, to one with many smaller military powers. In this environment, the United States cannot depend on the availability of operating bases from which to respond to crises requiring military intervention. Several studies (e.g. the SAB Global Reach, Global Power Study) have indicated an increased need to be able to rapidly transport large numbers of troops and equipment from the continental United States to potential trouble spots throughout the world. To this end, a request for proposals (RFP) for the concept design of a large aircraft capable of 'projecting' a significant military force without reliance on surface transportation was developed. These design requirements are: minimum payload of 400,000 pounds at 2.5 g maneuver load factor; minimum unfueled range of 6,000 nautical miles; and aircraft must operate from existing domestic air bases and use existing airbases or sites of opportunity at the destination.

  10. Aircraft landing using GPS

    NASA Astrophysics Data System (ADS)

    Lawrence, David Gary

    The advent of the Global Positioning System (GPS) is revolutionizing the field of navigation. Commercial aviation has been particularly influenced by this worldwide navigation system. From ground vehicle guidance to aircraft landing applications, GPS has the potential to impact many areas of aviation. GPS is already being used for non-precision approach guidance; current research focuses on its application to more critical regimes of flight. To this end, the following contributions were made: (1) Development of algorithms and a flexible software architecture capable of providing real-time position solutions accurate to the centimeter level with high integrity. This architecture was used to demonstrate 110 automatic landings of a Boeing 737. (2) Assessment of the navigation performance provided by two GPS-based landing systems developed at Stanford, the Integrity Beacon Landing System, and the Wide Area Augmentation System. (3) Preliminary evaluation of proposed enhancements to traditional techniques for GPS positioning, specifically, dual antenna positioning and pseudolite augmentation. (4) Introduction of a new concept for positioning using airport pseudolites. The results of this research are promising, showing that GPS-based systems can potentially meet even the stringent requirements of a Category III (zero visibility) landing system. Although technical and logistical hurdles still exist, it is likely that GPS will soon provide aircraft guidance in all phases of flight, including automatic landing, roll-out, and taxi.

  11. Hypersonic transport aircraft

    NASA Technical Reports Server (NTRS)

    1987-01-01

    A hypersonic transport aircraft design project was selected as a result of interactions with NASA Lewis Research Center personnel and fits the Presidential concept of the Orient Express. The Graduate Teaching Assistant (GTA) and an undergraduate student worked at the NASA Lewis Research Center during the 1986 summer conducting a literature survey, and relevant literature and useful software were collected. The computer software was implemented in the Computer Aided Design Laboratory of the Mechanical and Aerospace Engineering Department. In addition to the lectures by the three instructors, a series of guest lectures was conducted. The first of these lectures 'Anywhere in the World in Two Hours' was delivered by R. Luidens of NASA Lewis Center. In addition, videotaped copies of relevant seminars obtained from NASA Lewis were also featured. The first assignment was to individually research and develop the mission requirements and to discuss the findings with the class. The class in consultation with the instructors then developed a set of unified mission requirements. Then the class was divided into three design groups (1) Aerodynamics Group, (2) Propulsion Group, and (3) Structures and Thermal Analyses Group. The groups worked on their respective design areas and interacted with each other to finally come up with an integrated conceptual design. The three faculty members and the GTA acted as the resource persons for the three groups and aided in the integration of the individual group designs into the final design of a hypersonic aircraft.

  12. Altus aircraft on runway

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The remotely piloted Altus aircraft flew several developmental test flights from Rogers Dry Lake adjacent to NASA's Dryden Flight Research Center, Edwards, Calif., in 1996. The Altus--the word is Latin for 'high'--is a variant of the Predator surveillance drone built by General Atomics/Aeronautical Systems, Inc. It is designed for high-altitude, long-duration scientific sampling missions, and is powered by a turbocharged four-cylinder piston engine. The first Altus was developed under NASA's Environmental Research Aircraft and Sensor Technology program, while a second Altus was built for a Naval Postgraduate School/Department of Energy program. A pilot in a control station on the ground flew the craft by radio signals, using visual cues from a video camera in the nose of the Altus and information from the craft's air data system. Equipped with a single-stage turbocharger during the 1996 test flights, the first Altus reached altitudes in the 37,000-foot range, while the similarly-equipped second Altus reached 43,500 feet during developmental flights at Dryden in the summer of 1997. The NASA Altus also set an endurance record of more than 26 hours while flying a science mission in late 1996 and still had an estimated 10 hours of fuel remaining when it landed. Now equipped with a two-stage turbocharger, the NASA Altus maintained an altitude of 55,000 feet for four hours during flight tests in 1999.

  13. Flight testing and frequency domain analysis for rotorcraft handling qualities characteristics

    NASA Technical Reports Server (NTRS)

    Ham, Johnnie A.; Gardner, Charles K.; Tischler, Mark B.

    1993-01-01

    A demonstration of frequency domain flight testing techniques and analyses was performed on a U.S. Army OH-58D helicopter in support of the OH-58D Airworthiness and Flight Characteristics Evaluation and the Army's development and ongoing review of Aeronautical Design Standard 33C, Handling Qualities Requirements for Military Rotorcraft. Hover and forward flight (60 knots) tests were conducted in 1 flight hour by Army experimental test pilots. Further processing of the hover data generated a complete database of velocity, angular rate, and acceleration frequency responses to control inputs. A joint effort was then undertaken by the Airworthiness Qualification Test Directorate (AQTD) and the U.S. Army Aeroflightdynamics Directorate (AFDD) to derive handling qualities information from the frequency response database. A significant amount of information could be extracted from the frequency domain database using a variety of approaches. This report documents numerous results that have been obtained from the simple frequency domain tests; in many areas, these results provide more insight into the aircraft dynamics that affect handling qualities than to traditional flight tests. The handling qualities results include ADS-33C bandwidth and phase delay calculations, vibration spectral determinations, transfer function models to examine single axis results, and a six degree of freedom fully coupled state space model. The ability of this model to accurately predict aircraft responses was verified using data from pulse inputs. This report also documents the frequency-sweep flight test technique and data analysis used to support the tests.

  14. Evaluation of HiMAT aircraft landing approach lateral control gearing using simulation and a visual display

    NASA Technical Reports Server (NTRS)

    Sarrafian, S. K.

    1984-01-01

    The utility of a visual display when studying the influence of changes in lateral stick gearing gains on the Highly Maneuverable Aircraft Technology (HiMAT) vehicle handling qualities during simulated approaches and landings is investigated. The visual display improved the validity of the simulation and provided improved roll response cues for the HiMAT aircraft landing approach. A range of acceptable constant lateral stick gearing gains is found that provides adequate maneuverability and allows for precision moments.

  15. Steam Power Plants in Aircraft

    NASA Technical Reports Server (NTRS)

    Wilson, E E

    1926-01-01

    The employment of steam power plants in aircraft has been frequently proposed. Arguments pro and con have appeared in many journals. It is the purpose of this paper to make a brief analysis of the proposal from the broad general viewpoint of aircraft power plants. Any such analysis may be general or detailed.

  16. The Ultra Light Aircraft Testing

    NASA Technical Reports Server (NTRS)

    Smith, Howard W.

    1993-01-01

    The final report for grant NAG1-345 is presented. Recently, the bulk of the work that the grant has supported has been in the areas of ride quality and the structural analysis and testing of ultralight aircraft. The ride quality work ended in May 1989. Hence, the papers presented in this final report are concerned with ultralight aircraft.

  17. Composite Lightning Rods for Aircraft

    NASA Technical Reports Server (NTRS)

    Bryan, Charles F., Jr.

    1986-01-01

    Composite, lightweight sacrificial tip with graphite designed reduces lightning-strike damage to composite parts of aircraft and dissipates harmful electrical energy. Device consists of slender composite rod fabricated from highly-conductive unidirectional reinforcing fibers in matrix material. Rods strategically installed in trailing edges of aircraft wings, tails, winglets, control surfaces, and rearward-most portion of aft fuselage.

  18. Aircraft wiring program status report

    NASA Technical Reports Server (NTRS)

    Beach, Rex

    1995-01-01

    In this Naval Air Warfare Center (NAWC) Aircraft Division status report, the general and wire and cable component activities, the systems engineering activities, the aircraft wiring lead maintenance activities, the NAVAIR/NASA interface activities, and the Base Realignment and Closure (BRAC) Commission recommendations are presented.

  19. Fuel conservative aircraft engine technology

    NASA Technical Reports Server (NTRS)

    Nored, D. L.

    1978-01-01

    Technology developments for more fuel-efficiency subsonic transport aircraft are reported. Three major propulsion projects were considered: (1) engine component improvement - directed at current engines; (2) energy efficient engine - directed at new turbofan engines; and (3) advanced turboprops - directed at technology for advanced turboprop-powered aircraft. Each project is reviewed and some of the technologies and recent accomplishments are described.

  20. Acute Lymphoid Leukemia Cells with Greater Stem Cell Antigen-1 (Ly6a/Sca-1) Expression Exhibit Higher Levels of Metalloproteinase Activity and Are More Aggressive In Vivo

    PubMed Central

    Hsu, Yu-Chiao; Mildenstein, Kurt; Hunter, Kordell; Tkachenko, Olena; Mullen, Craig A.

    2014-01-01

    Stem cell antigen-1 (Ly6a/Sca-1) is a gene that is expressed in activated lymphocytes, hematopoietic stem cells and stem cells of a variety of tissues in mice. Despite decades of study its functions remain poorly defined. These studies explored the impact of expression of this stem cell associated gene in acute lymphoid leukemia. Higher levels of Ly6a/Sca-1 expression led to more aggressive leukemia growth in vivo and earlier death of hosts. Leukemias expressing higher levels of Ly6a/Sca-1 exhibited higher levels of matrix metalloproteinases. The results suggest the hypothesis that the more aggressive behavior of Ly6a/Sca-1 expressing leukemias is due at least in part to greater capacity to degrade microenvironmental stroma and invade tissues. PMID:24586463

  1. Constraint Handling in Transmission Network Expansion Planning

    NASA Astrophysics Data System (ADS)

    Mallipeddi, R.; Verma, Ashu; Suganthan, P. N.; Panigrahi, B. K.; Bijwe, P. R.

    Transmission network expansion planning (TNEP) is a very important and complex problem in power system. Recently, the use of metaheuristic techniques to solve TNEP is gaining more importance due to their effectiveness in handling the inequality constraints and discrete values over the conventional gradient based methods. Evolutionary algorithms (EAs) generally perform unconstrained search and require some additional mechanism to handle constraints. In EA literature, various constraint handling techniques have been proposed. However, to solve TNEP the penalty function approach is commonly used while the other constraint handling methods are untested. In this paper, we evaluate the performance of different constraint handling methods like Superiority of Feasible Solutions (SF), Self adaptive Penalty (SP),E-Constraint (EC), Stochastic Ranking (SR) and the ensemble of constraint handling techniques (ECHT) on TNEP. The potential of different constraint handling methods and their ensemble is evaluated using an IEEE 24 bus system with and without security constraints.

  2. Transfer Area Mechanical Handling Calculation

    SciTech Connect

    B. Dianda

    2004-06-23

    This calculation is intended to support the License Application (LA) submittal of December 2004, in accordance with the directive given by DOE correspondence received on the 27th of January 2004 entitled: ''Authorization for Bechtel SAX Company L.L. C. to Include a Bare Fuel Handling Facility and Increased Aging Capacity in the License Application, Contract Number DE-AC28-01R W12101'' (Arthur, W.J., I11 2004). This correspondence was appended by further Correspondence received on the 19th of February 2004 entitled: ''Technical Direction to Bechtel SAIC Company L.L. C. for Surface Facility Improvements, Contract Number DE-AC28-OIRW12101; TDL No. 04-024'' (BSC 2004a). These documents give the authorization for a Fuel Handling Facility to be included in the baseline. The purpose of this calculation is to establish preliminary bounding equipment envelopes and weights for the Fuel Handling Facility (FHF) transfer areas equipment. This calculation provides preliminary information only to support development of facility layouts and preliminary load calculations. The limitations of this preliminary calculation lie within the assumptions of section 5 , as this calculation is part of an evolutionary design process. It is intended that this calculation is superseded as the design advances to reflect information necessary to support License Application. The design choices outlined within this calculation represent a demonstration of feasibility and may or may not be included in the completed design. This calculation provides preliminary weight, dimensional envelope, and equipment position in building for the purposes of defining interface variables. This calculation identifies and sizes major equipment and assemblies that dictate overall equipment dimensions and facility interfaces. Sizing of components is based on the selection of commercially available products, where applicable. This is not a specific recommendation for the future use of these components or their related

  3. Electric lithosphere-astenosphere boundary in the north-west Fennoscandia as revealed from magnetotelluric data (MaSca project)

    NASA Astrophysics Data System (ADS)

    Cherevatova, M.; Smirnov, M.

    2014-12-01

    Magnetotelluric images of the electric lithosphere-astenosphere boundary (LAB) below the north-western Fennoscandian Shield show that thickest lithosphere is in the Proterozoic Domain, not in Archaean. The Magnetotelluric (MT) method is well suited to map the depth to the LAB. The electric lithosphere is defined as the resistive outer shell overlying a highly conducting zone (astenosphere) in the upper mantle. A few extensive field campaigns have been undertaken in the Summers of 2011 to 2014 within the framework of the project "Magnetotellurics in the Scandes". The MaSca survey crosses two important boundaries: (i) the transition zone from the stable Precambrian cratonic interior to passive continental margin beneath the Caledonian orogen and the Scandinavian Mountains in western Fennoscandia; (ii) the boundary between the Archaean and Proterozoic crust and upper mantle. In this study we present the electrical resistivity models obtained from 279 MT sites (70 long-period stations among them) acquired from 2011 to 2013. We also used other sources of data available in the study area: the IMAGE observatory data, the BEAR array and two small arrays of Finnish Geological Survey (GTK). We present the results of 2D lithospheric-scale inversions obtained along four selected profiles: three profiles are NW-SE directed, thought to be perpendicular to estimated regional strike and one profile crosses the Archaean-Proterozoic boundary, thus NE-SW directed. The final interpretation models revealed thickest lithosphere is in the Palaeoproterozoic Svecofennian province and reaches depth of 300 km. The Archaean lithosphere is thinner, with depth of 200 km to 250 km.

  4. Differential mtDNA damage patterns in a transgenic mouse model of Machado-Joseph disease (MJD/SCA3).

    PubMed

    Ramos, Amanda; Kazachkova, Nadiya; Silva, Francisca; Maciel, Patrícia; Silva-Fernandes, Anabela; Duarte-Silva, Sara; Santos, Cristina; Lima, Manuela

    2015-02-01

    Mitochondrial dysfunction has been associated with late onset neurodegenerative disorders, among which is Machado-Joseph disease (MJD/SCA3). In a previous study, using a transgenic mouse model of MJD, we reported a decrease in mitochondrial DNA (mtDNA) copy number and an accumulation of the 3876-bp deletion with age and with phenotype development. We extended this study by analyzing the pattern of mtDNA depletion and the accumulation of the 3876-bp deletion in 12 older transgenic (TG) and 4 wild-type (wt) animals, and by investigating the accumulation of somatic mutations in the D-loop region in 76 mice (42 TG and 34 wt). mtDNA damage was studied in TG and wt mice at different ages and tissues (blood, pontine nuclei, and hippocampus). Results for older mice demonstrate an accumulation of the mtDNA 3867-bp deletion with age, which was more pronounced in TG animals. Furthermore, the tendency for mtDNA copy number decrease with age, in all analyzed tissues of TG and wt animals, was also confirmed. No point mutations were detected in the D-loop, neither in TG nor wt animals, in any of the tissues analyzed. Due to the absence of mtDNA somatic mutations, we can suggest that mtDNA point mutation accumulation cannot be used to monitor the development and progression of the phenotype in this mouse model and likely in any MJD mice model. The present results further confirm not only the association between mtDNA alterations (copy number and deletions) and age, but also between such alterations and the expression of the mutant ataxin-3 in TG mice. PMID:25001003

  5. An miRNA-mediated therapy for SCA6 blocks IRES-driven translation of the CACNA1A second cistron.

    PubMed

    Miyazaki, Yu; Du, Xiaofei; Muramatsu, Shin-Ichi; Gomez, Christopher M

    2016-07-13

    Spinocerebellar ataxia type 6 (SCA6) is a dominantly inherited neurodegenerative disease characterized by slowly progressive ataxia and Purkinje cell degeneration. SCA6 is caused by a polyglutamine repeat expansion within a second CACNA1A gene product, α1ACT. α1ACT expression is under the control of an internal ribosomal entry site (IRES) present within the CACNA1A coding region. Whereas SCA6 allele knock-in mice show indistinguishable phenotypes from wild-type littermates, expression of SCA6-associated α1ACT (α1ACTSCA6) driven by a Purkinje cell-specific promoter in mice produces slowly progressive ataxia and cerebellar atrophy. We developed an early-onset SCA6 mouse model using an adeno-associated virus (AAV)-based gene delivery system to ectopically express CACNA1A IRES-driven α1ACTSCA6 to test the potential of CACNA1A IRES-targeting therapies. Mice expressing AAV9-mediated CACNA1A IRES-driven α1ACTSCA6 exhibited early-onset ataxia, motor deficits, and Purkinje cell degeneration. We identified miR-3191-5p as a microRNA (miRNA) that targeted CACNA1A IRES and preferentially inhibited the CACNA1A IRES-driven translation of α1ACT in an Argonaute 4 (Ago4)-dependent manner. We found that eukaryotic initiation factors (eIFs), eIF4AII and eIF4GII, interacted with the CACNA1A IRES to enhance α1ACT translation. Ago4-bound miR-3191-5p blocked the interaction of eIF4AII and eIF4GII with the CACNA1A IRES, attenuating IRES-driven α1ACT translation. Furthermore, AAV9-mediated delivery of miR-3191-5p protected mice from the ataxia, motor deficits, and Purkinje cell degeneration caused by CACNA1A IRES-driven α1ACTSCA6 We have established proof of principle that viral delivery of an miRNA can rescue a disease phenotype through modulation of cellular IRES activity in a mouse model. PMID:27412786

  6. CANISTER HANDLING FACILITY DESCRIPTION DOCUMENT

    SciTech Connect

    J.F. Beesley

    2005-04-21

    The purpose of this facility description document (FDD) is to establish requirements and associated bases that drive the design of the Canister Handling Facility (CHF), which will allow the design effort to proceed to license application. This FDD will be revised at strategic points as the design matures. This FDD identifies the requirements and describes the facility design, as it currently exists, with emphasis on attributes of the design provided to meet the requirements. This FDD is an engineering tool for design control; accordingly, the primary audience and users are design engineers. This FDD is part of an iterative design process. It leads the design process with regard to the flowdown of upper tier requirements onto the facility. Knowledge of these requirements is essential in performing the design process. The FDD follows the design with regard to the description of the facility. The description provided in this FDD reflects the current results of the design process.

  7. Intelligent packaging and material handling

    NASA Astrophysics Data System (ADS)

    Hall, Ernest L.; Shell, Richard; Slutzky, Gale D.

    1991-02-01

    The problem of palletizing (stacking on a pallet) randomly arriving mixed size and content parcels is an important task in most distribution warehouses. Today this task requires human interaction for a solution however recently several attempts have been made to automate the solution. The purpose of this paper is to present an overview of the problem an expert system approach and an estimate of the key subproblems which have been identified which are necessary for a solution. The concepts of space filling and emptying as encountered in warehousing are briefly described. Also brief descriptions of two generations of a robotic system for mixed parcel palletizing are presented. The results with these test systems indicate that automatic parcel handling at speeds comparable to humans is feasible however further work is required to obtain a robust solution.

  8. EXTREME -- Handling extreme data sets

    NASA Astrophysics Data System (ADS)

    Taylor, Mark

    This package provides some utilities, background documentation, and associated files for adapting the Starlink Software Collection, and software which uses it, to handle very large data sets. The principal focus of this is to move to use of 64 bits of address space on 64-bit operating systems. This document (SSN/73) is squarely aimed at the problem of adapting the Starlink Software Collection, and consequently focuses on the three operating systems (Solaris, Linux and Tru64) supported by Starlink, the compiled languages Fortran 77 and ANSI C, and Starlink's somewhat idiosyncratic build mechanisms. However, some of the discussion here may be of interest or use to people who are considering the change from 32 to 64 bits for software in other contexts.

  9. Conceptual design study of a Harrier V/STOL research aircraft

    NASA Technical Reports Server (NTRS)

    Bode, W. E.; Berger, R. L.; Elmore, G. A.; Lacey, T. R.

    1978-01-01

    MCAIR recently completed a conceptual design study to define modification approaches to, and derive planning prices for the conversion of a two place Harrier to a V/STOL control, display and guidance research aircraft. Control concepts such as rate damping, attitude stabilization, velocity command, and cockpit controllers are to be demonstrated. Display formats will also be investigated, and landing, navigation and guidance systems flight tested. The rear cockpit is modified such that it can be quickly adapted to faithfully simulate the controls, displays and handling qualities of a Type A or Type B V/STOL. The safety pilot always has take command capability. The modifications studied fall into two categories: basic modifications and optional modifications. Technical descriptions of the basic modifications and of the optional modifications are presented. The modification plan and schedule as well as the test plan and schedule are presented. The failure mode and effects analysis, aircraft performance, aircraft weight, and aircraft support are discussed.

  10. Integrated Payload Data Handling Demonstrator

    NASA Astrophysics Data System (ADS)

    FitzGeorge, T.; Wishart, A.; Hann, M.; Phan, N.; Carr, C. M.; Cupido, E.; Fox, P.; Oddy, T.; McGregor, A.; Marshall, A.; Waltham, N.

    2013-09-01

    An integrated Payload Data Handling System (IPDHS) is one in which multiple instruments share a central payload processor for their on-board data processing tasks. This offers a number of advantages over the conventional decentralised architecture. Savings in payload mass and power can be realised because the total processing resource is matched to the requirement, as opposed to the decentralised architecture where the processing resource is in effect the sum of all the applications. Overall development cost can be reduced using a common processor. At individual instrument level the potential benefits include a standardised application development environment, and the opportunity to run the instrument data handling application on a fully redundant and more powerful processor. This paper describes a joint programme by Astrium Ltd, SCISYS UK Limited, Imperial College London and RAL Space to implement a realistic demonstration of an I-PDHS using engineering models of flight instruments (a magnetometer and a camera) and a laboratory demonstrator of a central payload processor which is functionally representative of a flight design. The objective is to raise the Technology Readiness Level (TRL) of the centralised data processing technique by addressing the key areas of task partitioning to prevent fault propagation and the use of a common development process for the instrument applications. The project is supported by a UK Space Agency grant awarded under the National Space Technology Programme SpaceCITI scheme. The demonstration system is set up at the UK Space Agency's International Space Innovation Centre (ISIC) at Harwell and makes use of the ISIC Concurrent Design Facility (CDF).

  11. Complexity and Pilot Workload Metrics for the Evaluation of Adaptive Flight Controls on a Full Scale Piloted Aircraft

    NASA Technical Reports Server (NTRS)

    Hanson, Curt; Schaefer, Jacob; Burken, John J.; Larson, David; Johnson, Marcus

    2014-01-01

    Flight research has shown the effectiveness of adaptive flight controls for improving aircraft safety and performance in the presence of uncertainties. The National Aeronautics and Space Administration's (NASA)'s Integrated Resilient Aircraft Control (IRAC) project designed and conducted a series of flight experiments to study the impact of variations in adaptive controller design complexity on performance and handling qualities. A novel complexity metric was devised to compare the degrees of simplicity achieved in three variations of a model reference adaptive controller (MRAC) for NASA's F-18 (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) Full-Scale Advanced Systems Testbed (Gen-2A) aircraft. The complexity measures of these controllers are also compared to that of an earlier MRAC design for NASA's Intelligent Flight Control System (IFCS) project and flown on a highly modified F-15 aircraft (McDonnell Douglas, now The Boeing Company, Chicago, Illinois). Pilot comments during the IRAC research flights pointed to the importance of workload on handling qualities ratings for failure and damage scenarios. Modifications to existing pilot aggressiveness and duty cycle metrics are presented and applied to the IRAC controllers. Finally, while adaptive controllers may alleviate the effects of failures or damage on an aircraft's handling qualities, they also have the potential to introduce annoying changes to the flight dynamics or to the operation of aircraft systems. A nuisance rating scale is presented for the categorization of nuisance side-effects of adaptive controllers.

  12. Flight testing the Rotor Systems Research Aircraft (RSRA)

    NASA Technical Reports Server (NTRS)

    Merrill, R. K.; Hall, G. W.

    1982-01-01

    The Rotor Systems Research Aircraft (RSRA) is a dedicated rotor test vehicle whose function is to fill the gap between theory, wind tunnel tests and flight verification data. Its flight test envelope has been designed to encompass the expected envelopes of future rotor systems under all flight conditions. The test configurations of the RSRA include pure helicopter and compound (winged helicopter) modes. In addition, should it become necessary to jettison an unstable rotor system in flight, the RSRA may be flown as a fixed wing aircraft. The heart of the RSRA's electronic flight control system is the TDY-43 computer, which can be programmed in numerous ways to change stability and control or force feel system gains. Computer programming changes allow the RSRA to be used as a five-degree-of-freedom inflight simulator for studying the handling qualities of research rotors.

  13. Direct Adaptive Aircraft Control Using Dynamic Cell Structure Neural Networks

    NASA Technical Reports Server (NTRS)

    Jorgensen, Charles C.

    1997-01-01

    A Dynamic Cell Structure (DCS) Neural Network was developed which learns topology representing networks (TRNS) of F-15 aircraft aerodynamic stability and control derivatives. The network is integrated into a direct adaptive tracking controller. The combination produces a robust adaptive architecture capable of handling multiple accident and off- nominal flight scenarios. This paper describes the DCS network and modifications to the parameter estimation procedure. The work represents one step towards an integrated real-time reconfiguration control architecture for rapid prototyping of new aircraft designs. Performance was evaluated using three off-line benchmarks and on-line nonlinear Virtual Reality simulation. Flight control was evaluated under scenarios including differential stabilator lock, soft sensor failure, control and stability derivative variations, and air turbulence.

  14. Tilt Rotor Aircraft Aeroacoustics

    NASA Technical Reports Server (NTRS)

    George, Albert R.

    1996-01-01

    A fleet of civil tilt rotor transports offers a means of reducing airport congestion and point-to-point travel time. The speed, range, and fuel economy of these aircraft, along with their efficient use of vertiport area, make them good candidates for short-to-medium range civil transport. However, to be successfully integrated into the civilian community, the tilt rotor must be perceived as a quiet, safe, and economical mode of transportation that does not harm the environment. In particular, noise impact has been identified as a possible barrier to the civil tilt rotor. Along with rotor conversion-mode flight, and blade-vortex interaction noise during descent, hover mode is a noise problem for tilt rotor operations. In the present research, tilt rotor hover aeroacoustics have been studied analytically, experimentally, and computationally. Various papers on the subject were published as noted in the list of publications. More recently, experimental measurements were made on a 1/12.5 scale model of the XV-15 in hover and analyses of this data and extrapolations to full scale were also carried out. A dimensional analysis showed that the model was a good aeroacoustic approximation to the full-scale aircraft, and scale factors were derived to extrapolate the model measurements to the full-scale XV-15. The experimental measurements included helium bubble flow visualization, silk tuft flow visualization, 2-component hot wire anemometry, 7-hole pressure probe measurements, vorticity measurements, and outdoor far field acoustic measurements. The hot wire measurements were used to estimate the turbulence statistics of the flow field into the rotors, such as length scales, velocity scales, dissipation, and turbulence intermittency. Several different configurations of the model were tested: (1) standard configurations (single isolated rotor, two rotors without the aircraft, standard tilt rotor configuration); (2) flow control devices (the 'plate', the 'diagonal fences'); (3

  15. Handling Qualities Influences on Civil Tiltrotor Terminal Operating Procedure Development

    NASA Technical Reports Server (NTRS)

    Decker, William A.; Simmons, Rickey C.; Tucker, George E.; Aiken, Edwin W. (Technical Monitor)

    1994-01-01

    The potential for tiltrotor aircraft as civil transports has been well recognized. Realization of that potential requires development of operating procedures tailored to take advantage of the tiltrotor's capabilities, including thrust vectoring independent of body pitch attitude and good low-speed control. While the tiltrotor shares flight characteristics with both fixed wing airplanes and helicopters, it must convert between those flight modes, typically within the context of precise terminal operations. A series of piloted simulation experiments has been conducted on the NASA Ames Research Center Vertical Motion Simulator (VMS) to investigate the influence of tiltrotor cockpit design features on developing certification and operating criteria for civil tiltrotor transports. Handling qualities evaluations have shaped cockpit design guidelines and operating procedure development for a civil tiltrotor. In particular, four topics demonstrate the interplay of handling qualities and operations profile in the development of terminal operating procedures and cockpit or control equipment for a civil tiltrotor: conversion (airplane to helicopter mode), final approach path angle, operating profile speeds and speed changes (particularly under instrument conditions), and one engine inoperative operational considerations.

  16. Aircraft agility maneuvers

    NASA Technical Reports Server (NTRS)

    Cliff, Eugene M.; Thompson, Brian G.

    1992-01-01

    A new dynamic model for aircraft motions is presented. This model can be viewed as intermediate between a point-mass model, in which the body attitude angles are control-like, and a rigid-body model, in which the body-attitude angles evolve according to Newton's Laws. Specifically, consideration is given to the case of symmetric flight, and a model is constructed in which the body roll-rate and the body pitch-rate are the controls. In terms of this body-rate model a minimum-time heading change maneuver is formulated. When the bounds on the body-rates are large the results are similar to the point-mass model in that the model can very quickly change the applied forces and produce an acceleration to turn the vehicle. With finite bounds on these rates, the forces change in a smooth way. This leads to a measurable effect of agility.

  17. Alternative aircraft fuels

    NASA Technical Reports Server (NTRS)

    Longwell, J. P.; Grobman, J.

    1978-01-01

    In connection with the anticipated impossibility to provide on a long-term basis liquid fuels derived from petroleum, an investigation has been conducted with the objective to assess the suitability of jet fuels made from oil shale and coal and to develop a data base which will allow optimization of future fuel characteristics, taking energy efficiency of manufacture and the tradeoffs in aircraft and engine design into account. The properties of future aviation fuels are examined and proposed solutions to problems of alternative fuels are discussed. Attention is given to the refining of jet fuel to current specifications, the control of fuel thermal stability, and combustor technology for use of broad specification fuels. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source.

  18. Aircraft Engine Systems

    NASA Technical Reports Server (NTRS)

    Veres, Joseph

    2001-01-01

    This report outlines the detailed simulation of Aircraft Turbofan Engine. The objectives were to develop a detailed flow model of a full turbofan engine that runs on parallel workstation clusters overnight and to develop an integrated system of codes for combustor design and analysis to enable significant reduction in design time and cost. The model will initially simulate the 3-D flow in the primary flow path including the flow and chemistry in the combustor, and ultimately result in a multidisciplinary model of the engine. The overnight 3-D simulation capability of the primary flow path in a complete engine will enable significant reduction in the design and development time of gas turbine engines. In addition, the NPSS (Numerical Propulsion System Simulation) multidisciplinary integration and analysis are discussed.

  19. Aircraft control system

    NASA Technical Reports Server (NTRS)

    Lisoski, Derek L. (Inventor); Kendall, Greg T. (Inventor)

    2007-01-01

    A solar rechargeable, long-duration, span-loaded flying wing, having no fuselage or rudder. Having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn, pitch and yaw. The wing is configured to deform under flight loads to position the propellers such that the control can be achieved. Each of five segments of the wing has one or more motors and photovoltaic arrays, and produces its own lift independent of the other segments, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface.

  20. Aircraft vortex marking program

    NASA Technical Reports Server (NTRS)

    Pompa, M. F.

    1979-01-01

    A simple, reliable device for identifying atmospheric vortices, principally as generated by in-flight aircraft and with emphasis on the use of nonpolluting aerosols for marking by injection into such vortex (-ices) is presented. The refractive index and droplet size were determined from an analysis of aerosol optical and transport properties as the most significant parameters in effecting vortex optimum light scattering (for visual sighting) and visual persistency of at least 300 sec. The analysis also showed that a steam-ejected tetraethylene glycol aerosol with droplet size near 1 micron and refractive index of approximately 1.45 could be a promising candidate for vortex marking. A marking aerosol was successfully generated with the steam-tetraethylene glycol mixture from breadboard system hardware. A compact 25 lb/f thrust (nominal) H2O2 rocket chamber was the key component of the system which produced the required steam by catalytic decomposition of the supplied H2O2.