Science.gov

Sample records for aircraft warning spheres

  1. Aircraft Cabin Turbulence Warning Experiment

    NASA Technical Reports Server (NTRS)

    Bogue, Rodney K.; Larcher, Kenneth

    2006-01-01

    New turbulence prediction technology offers the potential for advance warning of impending turbulence encounters, thereby allowing necessary cabin preparation time prior to the encounter. The amount of time required for passengers and flight attendants to be securely seated (that is, seated with seat belts fastened) currently is not known. To determine secured seating-based warning times, a consortium of aircraft safety organizations have conducted an experiment involving a series of timed secured seating trials. This demonstrative experiment, conducted on October 1, 2, and 3, 2002, used a full-scale B-747 wide-body aircraft simulator, human passenger subjects, and supporting staff from six airlines. Active line-qualified flight attendants from three airlines participated in the trials. Definitive results have been obtained to provide secured seating-based warning times for the developers of turbulence warning technology

  2. 32 CFR 707.4 - Aircraft warning lights.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Aircraft warning lights. 707.4 Section 707.4... RESPECT TO ADDITIONAL STATION AND SIGNAL LIGHTS § 707.4 Aircraft warning lights. Naval vessels may display, as a means of indicating the presence of an obstruction to low flying aircraft, one all round...

  3. 32 CFR 707.4 - Aircraft warning lights.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 5 2011-07-01 2011-07-01 false Aircraft warning lights. 707.4 Section 707.4... RESPECT TO ADDITIONAL STATION AND SIGNAL LIGHTS § 707.4 Aircraft warning lights. Naval vessels may display, as a means of indicating the presence of an obstruction to low flying aircraft, one all round...

  4. 32 CFR 707.4 - Aircraft warning lights.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Aircraft warning lights. 707.4 Section 707.4... RESPECT TO ADDITIONAL STATION AND SIGNAL LIGHTS § 707.4 Aircraft warning lights. Naval vessels may display, as a means of indicating the presence of an obstruction to low flying aircraft, one all round...

  5. 32 CFR 707.4 - Aircraft warning lights.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 5 2013-07-01 2013-07-01 false Aircraft warning lights. 707.4 Section 707.4... RESPECT TO ADDITIONAL STATION AND SIGNAL LIGHTS § 707.4 Aircraft warning lights. Naval vessels may display, as a means of indicating the presence of an obstruction to low flying aircraft, one all round...

  6. 32 CFR 707.4 - Aircraft warning lights.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 5 2014-07-01 2014-07-01 false Aircraft warning lights. 707.4 Section 707.4... RESPECT TO ADDITIONAL STATION AND SIGNAL LIGHTS § 707.4 Aircraft warning lights. Naval vessels may display, as a means of indicating the presence of an obstruction to low flying aircraft, one all round...

  7. Aircraft Low Altitude Wind Shear Detection and Warning System.

    NASA Astrophysics Data System (ADS)

    Sinclair, Peter C.; Kuhn, Peter M.

    1991-01-01

    There is now considerable evidence to substantiate the causal relationship between low altitude wind shear (LAWS) and the recent increase in low-altitude aircraft accidents. The National Research Council has found that for the period 1964 to 1982, LAWS was involved in nearly all the weather-related air carrier fatalities. However, at present, there is no acceptable method, technique, or hardware system that provides the necessary safety margins, for spatial and timely detection of LAWS from an aircraft during the critical phases of landing and takeoff. The Federal Aviation Administration (FAA) has addressed this matter and supports the development of an airborne system for detecting hazardous LAWS with at least a one minute warning of the potential hazard to the pilot. One of the purposes of this paper is to show from some of our preliminary flight measurement research that a forward looking infrared radiometer (FLIR) system can be used to successfully detect the cool downdraft of downbursts [microbursts/macrobursts (MB)] and thunderstorm gust front outflows that are responsible for most of the LAWS events. The FLIR system provides a much greater safety margin for the pilot than that provided by reactive designs such as inertial-air speed systems that require the actual penetration of the MB before a pilot warning can be initiated. Our preliminary results indicate that an advanced airborne FLIR system could provide the pilot with remote indication of MB threat, location, movement, and predicted MB hazards along the flight path ahead of the aircraft.In a proof-of-concept experiment, we have flight tested a prototype FLIR system (nonscanning, fixed range) near and within Colorado MBs with excellent detectability. The results show that a minimum warning time of one-four minutes (5×10 km), depending on aircraft speed, is available to the pilot prior to a MB encounter. Analysis of the flight data with respect to a modified `hazard index' indicates the severe hazard

  8. National plans for aircraft icing and improved aircraft icing forecasts and associated warning services

    NASA Technical Reports Server (NTRS)

    Pass, Ralph P.

    1988-01-01

    Recently, the United States has increased its activities related to aircraft icing in numerous fields: ice phobics, revised characterization of icing conditions, instrument development/evaluation, de-ice/anti-ice devices, simulated supercooled clouds, computer simulation and flight tests. The Federal Coordinator for Meteorology is involved in two efforts, one a National Plan on Aircraft Icing and the other a plan for Improved Aircraft Icing Forecasts and Associated Warning Services. These two plans will provide an approved structure for future U.S. activities related to aircraft icing. The recommended activities will significantly improve the position of government agencies to perform mandated activities and to enable U.S. manufacturers to be competitive in the world market.

  9. User involvement in the early stages of the development of an aircraft warning system.

    PubMed

    Noyes, J M; Starr, A F; Frankish, C R

    1996-01-01

    There is an increasing awareness of the importance and the benefits to be attained from consulting the end-users during system and product development. Although the rationale of utilizing the expertise of end-users in the system development life cycle appears to provide an apparently straightforward, even 'ideal' approach, there are many difficulties associated with eliciting the required knowledge from experts, both general and specific to every user group. Furthermore, many developers do not know how to involve users, or if they do, they do not utilize them to best effect. In the avionics sphere, the wealth of knowledge possessed by line pilots and flight engineers represents a vital information resource for the design of future flight-deck systems. As a specific example, this paper overviews some of the considerations which arose from working with these end-users in the early stages of the development of a warning and diagnostic system for civil aircraft. The end-goal of this particular phase of the work was the generation of guidelines for the design of the interface for the software engineers to use when building the prototype, and the methodological approach taken to achieve this is reported here.

  10. User involvement in the early stages of the development of an aircraft warning system.

    PubMed

    Noyes, J M; Starr, A F; Frankish, C R

    1996-01-01

    There is an increasing awareness of the importance and the benefits to be attained from consulting the end-users during system and product development. Although the rationale of utilizing the expertise of end-users in the system development life cycle appears to provide an apparently straightforward, even 'ideal' approach, there are many difficulties associated with eliciting the required knowledge from experts, both general and specific to every user group. Furthermore, many developers do not know how to involve users, or if they do, they do not utilize them to best effect. In the avionics sphere, the wealth of knowledge possessed by line pilots and flight engineers represents a vital information resource for the design of future flight-deck systems. As a specific example, this paper overviews some of the considerations which arose from working with these end-users in the early stages of the development of a warning and diagnostic system for civil aircraft. The end-goal of this particular phase of the work was the generation of guidelines for the design of the interface for the software engineers to use when building the prototype, and the methodological approach taken to achieve this is reported here. PMID:11541759

  11. Digital detection and processing of laser beacon signals for aircraft collision hazard warning

    NASA Technical Reports Server (NTRS)

    Sweet, L. M.; Miles, R. B.; Russell, G. F.; Tomeh, M. G.; Webb, S. G.; Wong, E. Y.

    1981-01-01

    A low-cost collision hazard warning system suitable for implementation in both general and commercial aviation is presented. Laser beacon systems are used as sources of accurate relative position information that are not dependent on communication between aircraft or with the ground. The beacon system consists of a rotating low-power laser beacon, detector arrays with special optics for wide angle acceptance and filtering of solar background light, microprocessors for proximity and relative trajectory computation, and pilot displays of potential hazards. The laser beacon system provides direct measurements of relative aircraft positions; using optimal nonlinear estimation theory, the measurements resulting from the current beacon sweep are combined with previous data to provide the best estimate of aircraft proximity, heading, minimium passing distance, and time to closest approach.

  12. Assessing Aircraft Supply Air to Recommend Compounds for Timely Warning of Contamination

    NASA Astrophysics Data System (ADS)

    Fox, Richard B.

    Taking aircraft out of service for even one day to correct fume-in-cabin events can cost the industry roughly $630 million per year in lost revenue. The quantitative correlation study investigated quantitative relationships between measured concentrations of contaminants in bleed air and probability of odor detectability. Data were collected from 94 aircraft engine and auxiliary power unit (APU) bleed air tests from an archival data set between 1997 and 2011, and no relationships were found. Pearson correlation was followed by regression analysis for individual contaminants. Significant relationships of concentrations of compounds in bleed air to probability of odor detectability were found (p<0.05), as well as between compound concentration and probability of sensory irritancy detectability. Study results may be useful to establish early warning levels. Predictive trend monitoring, a method to identify potential pending failure modes within a mechanical system, may influence scheduled down-time for maintenance as a planned event, rather than repair after a mechanical failure and thereby reduce operational costs associated with odor-in-cabin events. Twenty compounds (independent variables) were found statistically significant as related to probability of odor detectability (dependent variable 1). Seventeen compounds (independent variables) were found statistically significant as related to probability of sensory irritancy detectability (dependent variable 2). Additional research was recommended to further investigate relationships between concentrations of contaminants and probability of odor detectability or probability of sensory irritancy detectability for all turbine oil brands. Further research on implementation of predictive trend monitoring may be warranted to demonstrate how the monitoring process might be applied to in-flight application.

  13. Aircraft Instrument, Fire Protection, Warning, Communication, Navigation and Cabin Atmosphere Control System (Course Outline), Aviation Mechanics 3 (Air Frame): 9067.04.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    This document presents an outline for a 135-hour course designed to familiarize the student with manipulative skills and theoretical knowledge concerning aircraft instrument systems like major flight and engine instruments; fire protection and fire fighting systems; warning systems and navigation systems; aircraft cabin control systems, such as…

  14. Airlock caution and warning system

    NASA Technical Reports Server (NTRS)

    Mayfield, W. J.; Cork, L. Z.; Malchow, R. G.; Hornback, G. L.

    1972-01-01

    Caution and warning system, used to monitor performance and warn of hazards or out-of-limit conditions on space vehicles, may have application to aircraft and railway transit systems. System consists of caution and warning subsystem and emergency subsystem.

  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. 14 CFR 91.603 - Aural speed warning device.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aural speed warning device. 91.603 Section... Operating Requirements for Large and Transport Category Aircraft § 91.603 Aural speed warning device. No... aural speed warning device that complies with § 25.1303(c)(1)....

  18. 14 CFR 91.603 - Aural speed warning device.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aural speed warning device. 91.603 Section... Operating Requirements for Large and Transport Category Aircraft § 91.603 Aural speed warning device. No... aural speed warning device that complies with § 25.1303(c)(1)....

  19. 14 CFR 91.603 - Aural speed warning device.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Aural speed warning device. 91.603 Section... Operating Requirements for Large and Transport Category Aircraft § 91.603 Aural speed warning device. No... aural speed warning device that complies with § 25.1303(c)(1)....

  20. 14 CFR 91.603 - Aural speed warning device.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Aural speed warning device. 91.603 Section... Operating Requirements for Large and Transport Category Aircraft § 91.603 Aural speed warning device. No... aural speed warning device that complies with § 25.1303(c)(1)....

  1. 14 CFR 91.603 - Aural speed warning device.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Aural speed warning device. 91.603 Section... Operating Requirements for Large and Transport Category Aircraft § 91.603 Aural speed warning device. No... aural speed warning device that complies with § 25.1303(c)(1)....

  2. Warning Signs After Birth

    MedlinePlus

    ... Pregnancy > Postpartum care > Warning signs after birth Warning signs after birth E-mail to a friend Please ... infection Postpartum bleeding Postpartum depression (PPD) What warning signs should you look for? Call your provider if ...

  3. Stroke Warning Signs

    MedlinePlus

    ... News Advocate Stroke Warning Signs Quiz Stroke Warning Signs and Symptoms THINK YOU ARE HAVING A STROKE? ... Learn more stroke signs and symptoms >>>> Stroke Warning Signs Hip-Hop F.A.S.T. Video Updated Guidelines ...

  4. 14 CFR 135.154 - Terrain awareness and warning system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Terrain awareness and warning system. 135... Aircraft and Equipment § 135.154 Terrain awareness and warning system. (a) Airplanes manufactured after... passenger seats, excluding any pilot seat, unless that airplane is equipped with an approved...

  5. 14 CFR 135.154 - Terrain awareness and warning system.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Terrain awareness and warning system. 135... Aircraft and Equipment § 135.154 Terrain awareness and warning system. (a) Airplanes manufactured after... passenger seats, excluding any pilot seat, unless that airplane is equipped with an approved...

  6. 14 CFR 135.154 - Terrain awareness and warning system.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Terrain awareness and warning system. 135... Aircraft and Equipment § 135.154 Terrain awareness and warning system. (a) Airplanes manufactured after... passenger seats, excluding any pilot seat, unless that airplane is equipped with an approved...

  7. 14 CFR 135.154 - Terrain awareness and warning system.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Terrain awareness and warning system. 135... Aircraft and Equipment § 135.154 Terrain awareness and warning system. (a) Airplanes manufactured after... passenger seats, excluding any pilot seat, unless that airplane is equipped with an approved...

  8. 14 CFR 135.154 - Terrain awareness and warning system.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Terrain awareness and warning system. 135... Aircraft and Equipment § 135.154 Terrain awareness and warning system. (a) Airplanes manufactured after... passenger seats, excluding any pilot seat, unless that airplane is equipped with an approved...

  9. Accuracy and speed of response to different voice types in a cockpit voice warning system

    NASA Astrophysics Data System (ADS)

    Freedman, J.; Rumbaugh, W. A.

    1983-09-01

    Voice warning systems (VWS) in aircraft cockpits provide a valuable means of warning identification. Improvements in technology have made the VWS a viable addition to aircraft warning systems. This thesis was an experiment to determine the best voice type (male, female, or neutral machine) for use in a VWS for military aircraft. Different levels of engine background noise, signal to noise ratio of the warning message, and precursor delivery formats were used. The experiment had ten subjects performing a primary tracking task; at random intervals a voice warning was interjected, requiring that the subjects respond by pushing the correct button. The results of this experiment contradict some previous beliefs and findings. The male voice was associated with more accurate responses for voice warning systems in the military aircraft environment. For speed of response the results were more complicated; the male voice was generally more closely associated with faster response times for accurate responses.

  10. Report on ice formation on aircraft

    NASA Technical Reports Server (NTRS)

    1939-01-01

    The physical phenomena involved in the icing of aircraft have been analyzed and measured. Recommendations on warning devices are made as well as the different types of ice and glazing that can occur on airplanes are examined and discussed.

  11. Warning systems and public warning response

    SciTech Connect

    Sorensen, J.H.

    1993-09-01

    This background paper reviews current knowledge on warning systems and human response to warnings. It expands on an earlier paper prepared for a workshop on the Second Assessment on Natural Hazards, held in Estes Park, Colorado in July 1992. Although it has a North American perspective, many of the lessons learned are universally applicable. The paper addresses warning systems in terms of dissemination and does not cover physical science issues associated with prediction and forecast. Finally, it covers hazards with relatively short lead times -- 48 hours or less. It does not address topics such as long-term forecasts of earthquakes or volcanic eruptions or early famine warning systems.

  12. Wind gust warning verification

    NASA Astrophysics Data System (ADS)

    Primo, Cristina

    2016-07-01

    Operational meteorological centres around the world increasingly include warnings as one of their regular forecast products. Warnings are issued to warn the public about extreme weather situations that might occur leading to damages and losses. In forecasting these extreme events, meteorological centres help their potential users in preventing the damage or losses they might suffer. However, verifying these warnings requires specific methods. This is due not only to the fact that they happen rarely, but also because a new temporal dimension is added when defining a warning, namely the time window of the forecasted event. This paper analyses the issues that might appear when dealing with warning verification. It also proposes some new verification approaches that can be applied to wind warnings. These new techniques are later applied to a real life example, the verification of wind gust warnings at the German Meteorological Centre ("Deutscher Wetterdienst"). Finally, the results obtained from the latter are discussed.

  13. SPHERES Facility

    NASA Technical Reports Server (NTRS)

    Martinez, Andres; Benavides, Jose Victor; Ormsby, Steve L.; GuarnerosLuna, Ali

    2014-01-01

    Synchronized Position Hold, Engage, Reorient, Experimental Satellites (SPHERES) are bowling-ball sized satellites that provide a test bed for development and research into multi-body formation flying, multi-spacecraft control algorithms, and free-flying physical and material science investigations. Up to three self-contained free-flying satellites can fly within the cabin of the International Space Station (ISS), performing flight formations, testing of control algorithms or as a platform for investigations requiring this unique free-flying test environment. Each satellite is a self-contained unit with power, propulsion, computers, navigation equipment, and provides physical and electrical connections (via standardized expansion ports) for Principal Investigator (PI) provided hardware and sensors.

  14. An automated stall-speed warning system

    NASA Technical Reports Server (NTRS)

    Wilner, D. O.; Bever, G. A.

    1984-01-01

    The development and testing of a stall-speed warning system for the OV-1C was examined. NASA designed and built an automated stall-speed warning system which presents both airspeed and stall speed to the pilot. The airspeed and stall speed are computed in real time by monitoring the basic aerodynamic parameters (dynamic pressure, horizontal and vertical accelerations, and pressure altitude) and other parameters (elevator and flap positions, engine torques, and fuel flow). In addition, an aural warning at predetermined stall margins is presented to the pilot through a voice synthesizer. Once the system was designed and installed in the aircraft, a flight-test program of less than 20 hrs was anticipated to determine the stall-speed software coefficients. These coefficients would then be inserted in the system's software and then test flown over a period of about 10 hr for the purpose of evaluation.

  15. Orbital dynamics of two electrically charged conducting spheres

    NASA Astrophysics Data System (ADS)

    Hoffmeister, Brent K.; Meyer, Deseree A.; Atkins, Brad M.; Franks, Gavin A.; Fuchs, Joshua T.; Li, Lulu; Sliger, Chase W.; Thompson, Jennifer E.

    2010-10-01

    The similar forms of Coulomb's law of electrostatics and Newton's law of gravitation suggest that two oppositely charged spheres can orbit each other by means of the electrostatic force. We demonstrate electrostatic binary orbits using two oppositely charged graphite coated Styrofoam® spheres. The experiment was conducted on the NASA aircraft Weightless Wonder which simulates weightless conditions. Videos of 23 orbital attempts were analyzed to investigate the dynamics and orbital stability of the two sphere system. The results support predictions of a recently developed theory that establishes criteria for stable orbits between two conducting, electrically charged spheres.

  16. Timely Warning Update

    ERIC Educational Resources Information Center

    Stafford, Dolores

    2011-01-01

    A complaint received by the Department of Education alleged that Virginia Tech violated the "timely warning" requirements of the Clery Act on April 16, 2007, by not issuing specific campus-wide alerts once senior officials knew of the immediate threat to health and safety. The complaint also alleged that the University's timely warning policy, as…

  17. Commercial aircraft wake vortices

    NASA Astrophysics Data System (ADS)

    Gerz, Thomas; Holzäpfel, Frank; Darracq, Denis

    2002-04-01

    This paper discusses the problem of wake vortices shed by commercial aircraft. It presents a consolidated European view on the current status of knowledge of the nature and characteristics of aircraft wakes and of technical and operational procedures of minimizing and predicting the vortex strength and avoiding wake encounters. Methodological aspects of data evaluation and interpretation, like the description of wake ages, the characterization of wake vortices, and the proper evaluation of wake data from measurement and simulation, are addressed in the first part. In the second part an inventory of our knowledge is given on vortex characterization and control, prediction and monitoring of vortex decay, vortex detection and warning, vortex encounter models, and wake-vortex safety assessment. Each section is concluded by a list of questions and required actions which may help to guide further research activities. The primary objective of the joint international efforts in wake-vortex research is to avoid potentially hazardous wake encounters for aircraft. Shortened aircraft separations under appropriate meteorological conditions, whilst keeping or even increasing the safety level, is the ultimate goal. Reduced time delays on the tactical side and increased airport capacities on the strategic side will be the benefits of these ambitious ventures for the air transportation industry and services.

  18. SPHERES Smartphone Workbench

    NASA Video Gallery

    The Smart SPHERES space robot (Synchronized Position Hold, Engage, Reorient, Experimental Satellites) equipped with an Android smartphone performs a video survey inside of the International Space S...

  19. Sphere based fluid systems

    NASA Technical Reports Server (NTRS)

    Elleman, Daniel D. (Inventor); Wang, Taylor G. (Inventor)

    1989-01-01

    Systems are described for using multiple closely-packed spheres. In one system for passing fluid, a multiplicity of spheres lie within a container, with all of the spheres having the same outside diameter and with the spheres being closely nested in one another to create multiple interstitial passages of a known size and configuration and smooth walls. The container has an inlet and outlet for passing fluid through the interstitial passages formed between the nested spheres. The small interstitial passages can be used to filter out material, especially biological material such as cells in a fluid, where the cells can be easily destroyed if passed across sharp edges. The outer surface of the spheres can contain a material that absorbs a constitutent in the flowing fluid, such as a particular contamination gas, or can contain a catalyst to chemically react the fluid passing therethrough, the use of multiple small spheres assuring a large area of contact of these surfaces of the spheres with the fluid. In a system for storing and releasing a fluid such as hydrogen as a fuel, the spheres can include a hollow shell containing the fluid to be stored, and located within a compressable container that can be compressed to break the shells and release the stored fluid.

  20. Aircraft Contrails

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Captured in this scene is a series of aircraft contrails in a high traffic region over the northern Gulf of Mexico (27.0N, 85.5W). Contrails are caused by the hot engine exhaust of high flying aircraft interacting with moisture in the cold upper atmosphere and are common occurrances of high flying aircraft.

  1. Balls and Spheres

    ERIC Educational Resources Information Center

    Szekely, George

    2011-01-01

    This article describes an art lesson that allows students to set up and collect sphere canvases. Spheres move art away from a rectangular canvas into a dimension that requires new planning and painting. From balls to many other spherical canvases that bounce, roll, float and fly, art experiences are envisioned by students. Even if adults recognize…

  2. DETECTION OR WARNING SYSTEM

    DOEpatents

    Tillman, J E

    1953-10-20

    This patent application describes a sensitive detection or protective system capable of giving an alarm or warning upon the entrance or intrusion of any body into a defined area or zone protected by a radiation field of suitable direction or extent.

  3. Lorentzian fuzzy spheres

    NASA Astrophysics Data System (ADS)

    Chaney, A.; Lu, Lei; Stern, A.

    2015-09-01

    We show that fuzzy spheres are solutions of Lorentzian Ishibashi-Kawai-Kitazawa-Tsuchiya-type matrix models. The solutions serve as toy models of closed noncommutative cosmologies where big bang/crunch singularities appear only after taking the commutative limit. The commutative limit of these solutions corresponds to a sphere embedded in Minkowski space. This "sphere" has several novel features. The induced metric does not agree with the standard metric on the sphere, and, moreover, it does not have a fixed signature. The curvature computed from the induced metric is not constant, has singularities at fixed latitudes (not corresponding to the poles) and is negative. Perturbations are made about the solutions, and are shown to yield a scalar field theory on the sphere in the commutative limit. The scalar field can become tachyonic for a range of the parameters of the theory.

  4. High performance dash on warning air mobile, missile system. [intercontinental ballistic missiles - systems analysis

    NASA Technical Reports Server (NTRS)

    Levin, A. D.; Castellano, C. R.; Hague, D. S.

    1975-01-01

    An aircraft-missile system which performs a high acceleration takeoff followed by a supersonic dash to a 'safe' distance from the launch site is presented. Topics considered are: (1) technological feasibility to the dash on warning concept; (2) aircraft and boost trajectory requirements; and (3) partial cost estimates for a fleet of aircraft which provide 200 missiles on airborne alert. Various aircraft boost propulsion systems were studied such as an unstaged cryogenic rocket, an unstaged storable liquid, and a solid rocket staged system. Various wing planforms were also studied. Vehicle gross weights are given. The results indicate that the dash on warning concept will meet expected performance criteria, and can be implemented using existing technology, such as all-aluminum aircraft and existing high-bypass-ratio turbofan engines.

  5. SPHERES National Lab Facility

    NASA Technical Reports Server (NTRS)

    Benavides, Jose

    2014-01-01

    SPHERES is a facility of the ISS National Laboratory with three IVA nano-satellites designed and delivered by MIT to research estimation, control, and autonomy algorithms. Since Fall 2010, The SPHERES system is now operationally supported and managed by NASA Ames Research Center (ARC). A SPHERES Program Office was established and is located at NASA Ames Research Center. The SPHERES Program Office coordinates all SPHERES related research and STEM activities on-board the International Space Station (ISS), as well as, current and future payload development. By working aboard ISS under crew supervision, it provides a risk tolerant Test-bed Environment for Distributed Satellite Free-flying Control Algorithms. If anything goes wrong, reset and try again! NASA has made the capability available to other U.S. government agencies, schools, commercial companies and students to expand the pool of ideas for how to test and use these bowling ball-sized droids. For many of the researchers, SPHERES offers the only opportunity to do affordable on-orbit characterization of their technology in the microgravity environment. Future utilization of SPHERES as a facility will grow its capabilities as a platform for science, technology development, and education.

  6. Analysis of pilot warning indicator performance in terminal area traffic.

    NASA Technical Reports Server (NTRS)

    Ruetenik, J. R.; Lange, W. R.; Thompson, J. H.

    1971-01-01

    Three pilot warning indicator concepts for collision hazard avoidance are analyzed using computer fast-time simulation. A hazard measure is defined based on a 1/2-g maximum horizontal acceleration, a maximum climb or dive angle of 10 deg for each aircraft, and a 20-sec warning time, through escape completion. The traffic model is based on flight tracks recorded in the Atlanta terminal area over an 11 hr period during August 1967. The basic PWI concept studied alarms on range to flashing beacons mounted on intruder aircraft as a function of relative azimuth and elevation. The alarm-hazard epoch ratio is about 17/1 to maintain the missed-alarm rate below 10%. Beacon vignetting or range-rate discrimination are shown to reduce the false-alarm rate by about 75%.

  7. Experiment SPHERE status 2008

    NASA Astrophysics Data System (ADS)

    Shaulov, S. B.; Besshapov, S. P.; Kabanova, N. V.; Sysoeva, T. I.; Antonov, R. A.; Anyuhina, A. M.; Bronvech, E. A.; Chernov, D. V.; Galkin, V. I.; Tkaczyk, W.; Finger, M.; Sonsky, M.

    2009-12-01

    The expedition carried out in March, 2008 to Lake Baikal became an important stage in the development of the SPHERE experiment. During the expedition the SPHERE-2 installation was hoisted, for the first time, on a tethered balloon, APA, to a height of 700 m over the lake surface covered with ice and snow. A series of test measurements were made. Preliminary results of the data processing are presented. The next plan of the SPHERE experiment is to begin a set of statistics for constructing the CR spectrum in the energy range 10-10 eV.

  8. Exploring the Role of Social Memory of Floods for Designing Flood Early Warning Operations

    NASA Astrophysics Data System (ADS)

    Girons Lopez, Marc; Di Baldassarre, Giuliano; Grabs, Thomas; Halldin, Sven; Seibert, Jan

    2016-04-01

    Early warning systems are an important tool for natural disaster mitigation practices, especially for flooding events. Warnings rely on near-future forecasts to provide time to take preventive actions before a flood occurs, thus reducing potential losses. However, on top of the technical capacities, successful warnings require an efficient coordination and communication among a range of different actors and stakeholders. The complexity of integrating the technical and social spheres of warning systems has, however, resulted in system designs neglecting a number of important aspects such as social awareness of floods thus leading to suboptimal results. A better understanding of the interactions and feedbacks among the different elements of early warning systems is therefore needed to improve their efficiency and therefore social resilience. When designing an early warning system two important decisions need to be made regarding (i) the hazard magnitude at and from which a warning should be issued and (ii) the degree of confidence required for issuing a warning. The first decision is usually taken based on the social vulnerability and climatic variability while the second one is related to the performance (i.e. accuracy) of the forecasting tools. Consequently, by estimating the vulnerability and the accuracy of the forecasts, these two variables can be optimized to minimize the costs and losses. Important parameters with a strong influence on the efficiency of warning systems such as social awareness are however not considered in their design. In this study we present a theoretical exploration of the impact of social awareness on the design of early warning systems. For this purpose we use a definition of social memory of flood events as a proxy for flood risk awareness and test its effect on the optimization of the warning system design variables. Understanding the impact of social awareness on warning system design is important to make more robust warnings that can

  9. Airburst warning and response

    NASA Astrophysics Data System (ADS)

    Boslough, Mark

    2014-10-01

    It is virtually certain (probability>99%) that the next destructive NEO event will be an airburst. Planetary defense is usually assumed to have the primary goal of maximizing the number of lives saved, but it can be argued that more emphasis should be placed on maximizing the probability of saving lives. For the latter goal, it is far more effective to create an early warning and civil defense plan than a mitigation plan that involves deflecting a large NEO. Because early warning and civil defense will almost certainly be needed long before the first deflection is ever required, the credibility of the planetary defense community and its recommendations will be put to its first serious test by an airburst. Successful response to an airburst event will make it much more likely that recommendations for mitigation by deflection will be accepted by decision makers and the public. Focusing more attention on the second goal will, as a side effect, benefit the primary goal.

  10. ISS Update: Smart SPHERES

    NASA Video Gallery

    NASA Public Affairs Officer Kelly Humphries conducts a phone interview with Mark Micire, SPHERES Engineering Manager at Ames Research Center. Questions? Ask us on Twitter @NASA_Johnson and include ...

  11. Catalytic, hollow, refractory spheres

    NASA Technical Reports Server (NTRS)

    Wang, Taylor G. (Inventor); Elleman, Daniel D. (Inventor); Lee, Mark C. (Inventor); Kendall, Jr., James M. (Inventor)

    1987-01-01

    Improved, heterogeneous, refractory catalysts are in the form of gas-impervious, hollow, thin-walled spheres (10) suitable formed of a shell (12) of refractory such as alumina having a cavity (14) containing a gas at a pressure greater than atmospheric pressure. The wall material may be itself catalytic or a catalytically active material coated onto the sphere as a layer (16), suitably platinum or iron, which may be further coated with a layer (18) of activator or promoter. The density of the spheres (30) can be uniformly controlled to a preselected value within .+-.10 percent of the density of the fluid reactant such that the spheres either remain suspended or slowly fall or rise through the liquid reactant.

  12. Catalytic hollow spheres

    NASA Technical Reports Server (NTRS)

    Wang, Taylor G. (Inventor); Elleman, Daniel D. (Inventor); Lee, Mark C. (Inventor); Kendall, Jr., James M. (Inventor)

    1989-01-01

    The improved, heterogeneous catalysts are in the form of gas-impervious, hollow, thin-walled spheres (10) suitably formed of a shell (12) of metal such as aluminum having a cavity (14) containing a gas at a pressure greater than atmospheric pressure. The wall material may be, itself, catalytic or the catalyst can be coated onto the sphere as a layer (16), suitably platinum or iron, which may be further coated with a layer (18) of activator or promoter. The density of the spheres (30) can be uniformly controlled to a preselected value within .+-.10 percent of the density of the fluid reactant such that the spheres either remain suspended or slowly fall or rise through the liquid reactant.

  13. Chinese Armillary Spheres

    NASA Astrophysics Data System (ADS)

    Sun, Xiaochun

    The armillary sphere was perhaps the most important type of astronomical instrument in ancient China. It was first invented by Luoxia Hong in the first century BC. After Han times, the structure of the armillary sphere became increasingly sophisticated by including more and more rings representing various celestial movements as recognized by the Chinese astronomers. By the eighth century, the Chinese armillary sphere consisted of three concentric sets of rings revolving on the south-north polar axis. The relative position of the rings could be adjusted to reflect the precession of the equinoxes and the regression of the Moon's nodes along the ecliptic. To counterbalance the defect caused by too many rings, Guo Shoujing from the late thirteenth century constructed the Simplified Instruments which reorganized the rings of the armillary sphere into separate instruments for measuring equatorial coordinates and horizontal coordinates. The armillary sphere was still preserved because it was a good illustration of celestial movements. A fifteenth-century replica of Guo Shoujing's armillary sphere still exists today.

  14. 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.

  15. Aircraft radar antennas

    NASA Astrophysics Data System (ADS)

    Schrank, Helmut E.

    1987-04-01

    Many changes have taken place in airborne radar antennas since their beginnings over forty years ago. A brief historical review of the advances in technology is presented, from mechanically scanned reflectors to modern multiple function phased arrays. However, emphasis is not on history but on the state-of-the-art technology and trends for future airborne radar systems. The status of rotating surveillance antennas is illustrated by the AN/APY-1 Airborne Warning and Control System (AWACS) slotted waveguide array, which achieved a significant breakthrough in sidelobe suppression. Gimballed flat plate arrays in nose radomes are typified by the AN/APG-66 (F-16) antenna. Multifunction phased arrays are presented by the Electronically Agile Radar (EAR) antenna, which has achieved significant advances in performance versatility and reliability. Trends toward active aperture, adaptive, and digital beamforming arrays are briefly discussed. Antennas for future aircraft radar systems must provide multiple functions in less aperture space, and must perform more reliably.

  16. Crowdsourced earthquake early warning.

    PubMed

    Minson, Sarah E; Brooks, Benjamin A; Glennie, Craig L; Murray, Jessica R; Langbein, John O; Owen, Susan E; Heaton, Thomas H; Iannucci, Robert A; Hauser, Darren L

    2015-04-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an M w (moment magnitude) 7 earthquake on California's Hayward fault, and real data from the M w 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing. PMID:26601167

  17. Crowdsourced earthquake early warning

    PubMed Central

    Minson, Sarah E.; Brooks, Benjamin A.; Glennie, Craig L.; Murray, Jessica R.; Langbein, John O.; Owen, Susan E.; Heaton, Thomas H.; Iannucci, Robert A.; Hauser, Darren L.

    2015-01-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an Mw (moment magnitude) 7 earthquake on California’s Hayward fault, and real data from the Mw 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing. PMID:26601167

  18. Crowdsourced earthquake early warning.

    PubMed

    Minson, Sarah E; Brooks, Benjamin A; Glennie, Craig L; Murray, Jessica R; Langbein, John O; Owen, Susan E; Heaton, Thomas H; Iannucci, Robert A; Hauser, Darren L

    2015-04-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an M w (moment magnitude) 7 earthquake on California's Hayward fault, and real data from the M w 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing.

  19. 49 CFR 234.259 - Warning time.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Warning time. 234.259 Section 234.259..., Inspection, and Testing Inspections and Tests § 234.259 Warning time. Each crossing warning system shall be tested for the prescribed warning time at least once every 12 months and when the warning system...

  20. Laser beacon system for aircraft collision hazard determination.

    PubMed

    Miles, R B

    1980-07-01

    A laser beacon collision hazard determination system is capable of simultaneously determining range, bearing, and heading of threat aircraft. Calculations demonstrate that threat aircraft may be observed at > 10 km under good visibility conditions. When the visibility is limited to 5.6 km (3 nautical miles), the shortest possible warning time for aircraft below 3000 m (10,000 ft) can be > 15 sec. A wide variety of detection systems may be chosen based on cost, detection range, and sophistication. Traffic saturation is not a problem since closer aircraft produce easily distinguishable signals so traffic may be prioritized. Preliminary tests demonstrate that accurate range measurements are possible under daylight conditions.

  1. Steering Aircraft Clear of Choppy Air

    NASA Technical Reports Server (NTRS)

    2006-01-01

    AeroTech Research (U.S.A.), Inc., a leader in turbulence-detection and warning systems, has been involved with NASA Aviation Safety research since 1998. AeroTech served as a contractor for the TPAWS government/industry development project, and was funded by NASA to develop the E-Turb Mode Radar algorithms and the TAPS software. (Other contributors to this project include the National Center for Atmospheric Research, the FAA, North Carolina State University, and the Research Triangle Institute.) The radar algorithms combine an aircraft's turbulenceresponse characteristics with radar measurements to determine the predicted turbulence loads the aircraft will experience, and present this information to the pilot. The TAPS software monitors and processes onboard aircraft sensor data; generates automatic reports when an aircraft encounters turbulence and a set turbulence threshold is exceeded; and then displays the reports and underlying information to ground personnel to improve situational awareness of the location and the severity of the turbulence encounter.

  2. Airborne Turbulence Detection and Warning ACLAIM Flight Test Results

    NASA Technical Reports Server (NTRS)

    Hannon, Stephen M.; Bagley, Hal R.; Soreide, Dave C.; Bowdle, David A.; Bogue, Rodney K.; Ehernberger, L. Jack

    1999-01-01

    The Airborne Coherent Lidar for Advanced Inflight Measurements (ACLAIM) is a NASA/Dryden-lead program to develop and demonstrate a 2 micrometers pulsed Doppler lidar for airborne look-ahead turbulence detection and warning. Advanced warning of approaching turbulence can significantly reduce injuries to passengers and crew aboard commercial airliners. The ACLAIM instrument is a key asset to the ongoing Turbulence component of NASA's Aviation Safety Program, aimed at reducing the accident rate aboard commercial airliners by a factor of five over the next ten years and by a factor of ten over the next twenty years. As well, the advanced turbulence warning capability can prevent "unstarts" in the inlet of supersonic aircraft engines by alerting the flight control computer which then adjusts the engine to operate in a less fuel efficient, and more turbulence tolerant, mode. Initial flight tests of the ACLAIM were completed in March and April of 1998. This paper and presentation gives results from these initial flights, with validated demonstration of Doppler lidar wind turbulence detection several kilometers ahead of the aircraft.

  3. Are heat warning systems effective?

    PubMed Central

    2013-01-01

    Heatwaves are associated with significant health risks particularly among vulnerable groups. To minimize these risks, heat warning systems have been implemented. The question therefore is how effective these systems are in saving lives and reducing heat-related harm. We systematically searched and reviewed 15 studies which examined this. Six studies asserted that fewer people died of excessive heat after the implementation of heat warning systems. Demand for ambulance decreased following the implementation of these systems. One study also estimated the costs of running heat warning systems at US$210,000 compared to the US$468 million benefits of saving 117 lives. The remaining eight studies investigated people’s response to heat warning systems and taking appropriate actions against heat harms. Perceived threat of heat dangers emerged as the main factor related to heeding the warnings and taking proper actions. However, barriers, such as costs of running air-conditioners, were of significant concern, particularly to the poor. The weight of the evidence suggests that heat warning systems are effective in reducing mortality and, potentially, morbidity. However, their effectiveness may be mediated by cognitive, emotive and socio-demographic characteristics. More research is urgently required into the cost-effectiveness of heat warning systems’ measures and improving the utilization of the services. PMID:23561265

  4. Sticky surface: sphere-sphere adhesion dynamics

    PubMed Central

    Sircar, Sarthok; Younger, John G.; Bortz, David M.

    2014-01-01

    We present a multi-scale model to study the attachment of spherical particles with a rigid core, coated with binding ligands and suspended in the surrounding, quiescent fluid medium. This class of fluid-immersed adhesion is widespread in many natural and engineering settings, particularly in microbial surface adhesion. Our theory highlights how the micro-scale binding kinetics of these ligands, as well as the attractive / repulsive surface potential in an ionic medium affects the eventual macro-scale size distribution of the particle aggregates (flocs). The bridge between the micro-macro model is made via an aggregation kernel. Results suggest that the presence of elastic ligands on the particle surface lead to the formation of larger floc aggregates via efficient inter-floc collisions (i.e., non-zero sticking probability, g). Strong electrolytic composition of the surrounding fluid favors large floc formation as well. The kernel for the Brownian diffusion for hard spheres is recovered in the limit of perfect binding effectiveness (g → 1) and in a neutral solution with no dissolved salts. PMID:25159830

  5. Parallel sphere rendering

    SciTech Connect

    Krogh, M.; Painter, J.; Hansen, C.

    1996-10-01

    Sphere rendering is an important method for visualizing molecular dynamics data. This paper presents a parallel algorithm that is almost 90 times faster than current graphics workstations. To render extremely large data sets and large images, the algorithm uses the MIMD features of the supercomputers to divide up the data, render independent partial images, and then finally composite the multiple partial images using an optimal method. The algorithm and performance results are presented for the CM-5 and the M.

  6. Toxicity Warning Badge

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Kennedy Space Center contracted GMD Systems, Inc., now Bacharach, Inc., to design a system for monitoring personnel exposure to hydrazine and monomethyl hydrazine, two dangerous gases which ignite on contact with an oxidizer. GMD developed a reliable colorimetric gas monitoring dosimeter for NASA, then modified it to create the commercial GMD 530 Series Hydrazine Badge. The badge has two separate paper tape chemistries which change color when the gases are detected, the density of the color being in proportion to the time of exposure and amount of gas in the air. The badge is used in facilities where hypergolic fuel is produced or used in support of space vehicles, satellites, missiles, and military aircraft auxiliary power units.

  7. 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.

  8. 49 CFR 234.259 - Warning time.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Warning time. 234.259 Section 234.259... time. Each crossing warning system shall be tested for the prescribed warning time at least once every... devices that accurately determine actual warning time may be used in performing such tests....

  9. 49 CFR 234.259 - Warning time.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Warning time. 234.259 Section 234.259... time. Each crossing warning system shall be tested for the prescribed warning time at least once every... devices that accurately determine actual warning time may be used in performing such tests....

  10. Cigarette Warning Labels as Educational Devices.

    ERIC Educational Resources Information Center

    Newman, Ian M.; And Others

    This paper reports an investigation on the educational impact of warning labels on cigarette packages on adolescents. Subjects were asked to identify the locations of warning labels on cigarette packages and advertising and to restate the warning label. Results indicated that official warnings may be well known in general terms but poorly known in…

  11. Parallel sphere rendering

    SciTech Connect

    Krogh, M.; Hansen, C.; Painter, J.; de Verdiere, G.C.

    1995-05-01

    Sphere rendering is an important method for visualizing molecular dynamics data. This paper presents a parallel divide-and-conquer algorithm that is almost 90 times faster than current graphics workstations. To render extremely large data sets and large images, the algorithm uses the MIMD features of the supercomputers to divide up the data, render independent partial images, and then finally composite the multiple partial images using an optimal method. The algorithm and performance results are presented for the CM-5 and the T3D.

  12. Affordable MMW aircraft collision avoidance system

    NASA Astrophysics Data System (ADS)

    Almsted, Larry D.; Becker, Robert C.; Zelenka, Richard E.

    1997-06-01

    Collision avoidance is of concern to all aircraft, requiring the detection and identification of hazardous terrain or obstacles in sufficient time for clearance maneuvers. The collision avoidance requirement is even more demanding for helicopters, as their unique capabilities result in extensive operations at low-altitude, near to terrain and other hazardous obstacles. TO augment the pilot's visual collision avoidance abilities, some aircraft are equipped with 'enhanced-vision' systems or terrain collision warning systems. Enhanced-vision systems are typically very large and costly systems that are not very covert and are also difficult to install in a helicopter. The display is typically raw images from infrared or radar sensors, and can require a high degree of pilot interpretation and attention. Terrain collision warning system that rely on stored terrain maps are often of low resolution and accuracy and do not represent hazards to the aircraft placed after map sampling. Such hazards could include aircraft parked on runway, man- made towers or buildings and hills. In this paper, a low cost dual-function scanning pencil-beam, millimeter-wave radar forward sensor is used to determine whether an aircraft's flight path is clear of obstructions. Due to the limited space and weight budget in helicopters, the system is a dual function system that is substituted in place of the existing radar altimeter. The system combines a 35 GHz forward looking obstacle avoidance radar and a 4.3 GHz radar altimeter. The forward looking 35 GHz 3D radar's returns are used to construct a terrain and obstruction database surrounding an aircraft, which is presented to the pilot as a synthetic perspective display. The 35 GHz forward looking radar and the associated display was evaluated in a joint NASA Honeywell flight test program in 1996. The tests were conducted on a NASA/Army test helicopter. The test program clearly demonstrated the systems potential usefulness for collision avoidance.

  13. Hypervelocity flow over spheres

    NASA Astrophysics Data System (ADS)

    Wen, Chihyung

    The nature of the nonequilibrium flow of dissociating gases over spheres was investigated experimentally, numerically and theoretically. A series of experiments with three different gases, nitrogen, air and carbon dioxide, was performed in the shock tunnel T5 at GALCIT. Five spheres of different radii equipped with thermocouples for surface heat flux measurements were used. The state-of-the-art numerical method by Candler (1988) was used to conduct a parallel study which strongly complemented the experimental and theoretical efforts.Experimental heat flux measurements are presented. Good agreement was observed among the measured stagnation point heat transfer rates, computational results and Fay and Riddell's theoretical predictions. For nitrogen and air, the measured heat flux distributions were also in good agreement with numerical computation results and Lees' theory. For carbon dioxide, large deviations were observed. Early transition tripped by surface roughness is a possible cause for the deviation of heat flux distribution from the theory. The experimental differential interferograms were compared with the images constructed from computational flowfields. Good agreement of fringe pattern and shock shape was observed.An analytical solution is obtained for inviscid hypervelocity dissociating flow over spheres. The solution explains the correlation between the dimensionless stand-off distance and the dimensionless reaction rate parameter previously observed by Hornung (1972) for nitrogen. The physics of the correlation can be shown as the binary scaling. Based on the solution, a new dimensionless reaction rate parameter is defined to generalize Hornung's correlation for more complex gases than nitrogen. Experimental and numerical results confirm the new correlation.The effect of nonequilibrium recombination downstream of a curved two-dimensional shock was also addressed. An analytical solution for an ideal dissociating gas was obtained, giving an expression for

  14. Combustion of a Polymer (PMMA) Sphere in Microgravity

    NASA Technical Reports Server (NTRS)

    Yang, Jiann C.; Hamins, Anthony; Donnelly, Michelle K.

    1999-01-01

    A series of low gravity, aircraft-based, experiments was conducted to investigate the combustion of supported thermoplastic polymer spheres under varying ambient conditions. The three types of thermoplastic investigated were polymethylmethacrylate (PMMA), polypropylene (PP). and polystyrene (PS). Spheres with diameters ranging from 2 mm to 6.35 mm were tested. The total initial pressure varied from 0.05 MPa to 0. 15 MPa whereas the ambient oxygen concentration varied from 19 % to 30 % (by volume). The ignition system consisted of a pair of retractable energized coils. Two CCD cameras recorded the burning histories of the spheres. The video sequences revealed a number of dynamic events including bubbling and sputtering, as well as soot shell formation and break-up during combustion of the spheres at reduced gravity. The ejection of combusting material from the burning spheres represents a fire hazard that must be considered at reduced gravity. The ejection process was found to be sensitive to polymer type. All average burning rates were measured to increase with initial sphere diameter and oxygen concentration, whereas the initial pressure had little effect. The three thermoplastic types exhibited different burning characteristics. For the same initial conditions, the burning rate of PP was slower than PMMA, whereas the burning rate of PS was comparable to PMMA. The transient diameter of the burning thermoplastic exhibited two distinct periods: an initial period (enduring approximately half of the total burn duration) when the diameter remained approximately constant, and a final period when the square of the diameter linearly decreased with time. A simple homogeneous two-phase model was developed to understand the changing diameter of the burning sphere. Its value is based on a competition between diameter reduction due to mass loss from burning and sputtering, and diameter expansion due to the processes of swelling (density decrease with heating) and bubble growth

  15. Panoramic stereo sphere vision

    NASA Astrophysics Data System (ADS)

    Feng, Weijia; Zhang, Baofeng; Röning, Juha; Zong, Xiaoning; Yi, Tian

    2013-01-01

    Conventional stereo vision systems have a small field of view (FOV) which limits their usefulness for certain applications. While panorama vision is able to "see" in all directions of the observation space, scene depth information is missed because of the mapping from 3D reference coordinates to 2D panoramic image. In this paper, we present an innovative vision system which builds by a special combined fish-eye lenses module, and is capable of producing 3D coordinate information from the whole global observation space and acquiring no blind area 360°×360° panoramic image simultaneously just using single vision equipment with one time static shooting. It is called Panoramic Stereo Sphere Vision (PSSV). We proposed the geometric model, mathematic model and parameters calibration method in this paper. Specifically, video surveillance, robotic autonomous navigation, virtual reality, driving assistance, multiple maneuvering target tracking, automatic mapping of environments and attitude estimation are some of the applications which will benefit from PSSV.

  16. Russian eruption warning systems for aviation

    USGS Publications Warehouse

    Neal, C.; Girina, O.; Senyukov, S.; Rybin, A.; Osiensky, J.; Izbekov, P.; Ferguson, G.

    2009-01-01

    More than 65 potentially active volcanoes on the Kamchatka Peninsula and the Kurile Islands pose a substantial threat to aircraft on the Northern Pacific (NOPAC), Russian Trans-East (RTE), and Pacific Organized Track System (PACOTS) air routes. The Kamchatka Volcanic Eruption Response Team (KVERT) monitors and reports on volcanic hazards to aviation for Kamchatka and the north Kuriles. KVERT scientists utilize real-time seismic data, daily satellite views of the region, real-time video, and pilot and field reports of activity to track and alert the aviation industry of hazardous activity. Most Kurile Island volcanoes are monitored by the Sakhalin Volcanic Eruption Response Team (SVERT) based in Yuzhno-Sakhalinsk. SVERT uses daily moderate resolution imaging spectroradiometer (MODIS) satellite images to look for volcanic activity along this 1,250-km chain of islands. Neither operation is staffed 24 h per day. In addition, the vast majority of Russian volcanoes are not monitored seismically in real-time. Other challenges include multiple time-zones and language differences that hamper communication among volcanologists and meteorologists in the US, Japan, and Russia who share the responsibility to issue official warnings. Rapid, consistent verification of explosive eruptions and determination of cloud heights remain significant technical challenges. Despite these difficulties, in more than a decade of frequent eruptive activity in Kamchatka and the northern Kuriles, no damaging encounters with volcanic ash from Russian eruptions have been recorded. ?? Springer Science+Business Media B.V. 2009.

  17. 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)

  18. Dynamical tachyons on fuzzy spheres

    SciTech Connect

    Berenstein, David; Trancanelli, Diego

    2011-05-15

    We study the spectrum of off-diagonal fluctuations between displaced fuzzy spheres in the Berenstein-Maldacena-Nastase plane wave matrix model. The displacement is along the plane of the fuzzy spheres. We find that when two fuzzy spheres intersect at angles, classical tachyons develop and that the spectrum of these modes can be computed analytically. These tachyons can be related to the familiar Nielsen-Olesen instabilities in Yang-Mills theory on a constant magnetic background. Many features of the problem become more apparent when we compare with maximally supersymmetric Yang-Mills theory on a sphere, of which this system is a truncation. We also set up a simple oscillatory trajectory on the displacement between the fuzzy spheres and study the dynamics of the modes as they become tachyonic for part of the oscillations. We speculate on their role regarding the possible thermalization of the system.

  19. Warning Signs of Vision Problems in Children

    MedlinePlus

    ... Text Size Email Print Share Warning Signs of Vision Problems in Infants & Children Page Content ​Eye exams ... treated successfully. What are warning signs of a vision problem? Babies up to 1 year of age: ...

  20. 49 CFR 193.2917 - Warning signs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Security § 193.2917 Warning signs. (a) Warning signs must be conspicuously...

  1. FDA Bolsters Warnings about Class of Antibiotics

    MedlinePlus

    ... 160078.html FDA Bolsters Warnings About Class of Antibiotics Fluoroquinolones such as Cipro, Levaquin should be reserved ... it's strengthening label warnings on a class of antibiotics called fluoroquinolones because the drugs can lead to ...

  2. Aircraft vulnerability analysis by modeling and simulation

    NASA Astrophysics Data System (ADS)

    Willers, Cornelius J.; Willers, Maria S.; de Waal, Alta

    2014-10-01

    Infrared missiles pose a significant threat to civilian and military aviation. ManPADS missiles are especially dangerous in the hands of rogue and undisciplined forces. Yet, not all the launched missiles hit their targets; the miss being either attributable to misuse of the weapon or to missile performance restrictions. This paper analyses some of the factors affecting aircraft vulnerability and demonstrates a structured analysis of the risk and aircraft vulnerability problem. The aircraft-missile engagement is a complex series of events, many of which are only partially understood. Aircraft and missile designers focus on the optimal design and performance of their respective systems, often testing only in a limited set of scenarios. Most missiles react to the contrast intensity, but the variability of the background is rarely considered. Finally, the vulnerability of the aircraft depends jointly on the missile's performance and the doctrine governing the missile's launch. These factors are considered in a holistic investigation. The view direction, altitude, time of day, sun position, latitude/longitude and terrain determine the background against which the aircraft is observed. Especially high gradients in sky radiance occur around the sun and on the horizon. This paper considers uncluttered background scenes (uniform terrain and clear sky) and presents examples of background radiance at all view angles across a sphere around the sensor. A detailed geometrical and spatially distributed radiometric model is used to model the aircraft. This model provides the signature at all possible view angles across the sphere around the aircraft. The signature is determined in absolute terms (no background) and in contrast terms (with background). It is shown that the background significantly affects the contrast signature as observed by the missile sensor. A simplified missile model is constructed by defining the thrust and mass profiles, maximum seeker tracking rate, maximum

  3. 30 CFR 57.14214 - Train warnings.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Train warnings. 57.14214 Section 57.14214... Equipment Safety Practices and Operational Procedures § 57.14214 Train warnings. A warning that is audible above the surrounding noise level shall be sounded— (a) Immediately prior to moving trains; (b)...

  4. 30 CFR 56.14214 - Train warnings.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Train warnings. 56.14214 Section 56.14214... Safety Practices and Operational Procedures § 56.14214 Train warnings. A warning that is audible above the surrounding noise level shall be sounded— (a) Immediately prior to moving trains; (b) When...

  5. 30 CFR 57.14208 - Warning devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Warning devices. 57.14208 Section 57.14208... Equipment Safety Practices and Operational Procedures § 57.14208 Warning devices. (a) Visible warning devices shall be used when parked mobile equipment creates a hazard to persons in other mobile...

  6. 30 CFR 56.14208 - Warning devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Warning devices. 56.14208 Section 56.14208 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Practices and Operational Procedures § 56.14208 Warning devices. (a) Visible warning devices...

  7. 46 CFR 154.1830 - Warning sign.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Warning sign. 154.1830 Section 154.1830 Shipping COAST... SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Operations § 154.1830 Warning sign. (a) The master... a warning sign: (1) At the gangway facing the shore so that the sign may be seen from the shore;...

  8. 49 CFR 193.2917 - Warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Warning signs. 193.2917 Section 193.2917...: FEDERAL SAFETY STANDARDS Security § 193.2917 Warning signs. (a) Warning signs must be conspicuously placed along each protective enclosure at intervals so that at least one sign is recognizable at night from...

  9. 49 CFR 193.2917 - Warning signs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Warning signs. 193.2917 Section 193.2917...: FEDERAL SAFETY STANDARDS Security § 193.2917 Warning signs. (a) Warning signs must be conspicuously placed along each protective enclosure at intervals so that at least one sign is recognizable at night from...

  10. 46 CFR 154.1830 - Warning sign.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Warning sign. 154.1830 Section 154.1830 Shipping COAST... SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Operations § 154.1830 Warning sign. (a) The master... a warning sign: (1) At the gangway facing the shore so that the sign may be seen from the shore;...

  11. 49 CFR 193.2917 - Warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Warning signs. 193.2917 Section 193.2917...: FEDERAL SAFETY STANDARDS Security § 193.2917 Warning signs. (a) Warning signs must be conspicuously placed along each protective enclosure at intervals so that at least one sign is recognizable at night from...

  12. 49 CFR 193.2917 - Warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Warning signs. 193.2917 Section 193.2917...: FEDERAL SAFETY STANDARDS Security § 193.2917 Warning signs. (a) Warning signs must be conspicuously placed along each protective enclosure at intervals so that at least one sign is recognizable at night from...

  13. 16 CFR 307.2 - Required warnings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... THE COMPREHENSIVE SMOKELESS TOBACCO HEALTH EDUCATION ACT OF 1986 Scope § 307.2 Required warnings. The Comprehensive Smokeless Tobacco Health Education Act of 1986 is the law that requires the enactment of these... smokeless tobacco product. The warning statements required by the Act are as follows: WARNING: THIS...

  14. 30 CFR 56.14214 - Train warnings.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Safety Practices and Operational Procedures § 56.14214 Train warnings. A warning that is audible above... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Train warnings. 56.14214 Section 56.14214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL...

  15. 30 CFR 56.14214 - Train warnings.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Safety Practices and Operational Procedures § 56.14214 Train warnings. A warning that is audible above... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Train warnings. 56.14214 Section 56.14214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL...

  16. 30 CFR 57.14214 - Train warnings.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Equipment Safety Practices and Operational Procedures § 57.14214 Train warnings. A warning that is audible... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Train warnings. 57.14214 Section 57.14214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL...

  17. 30 CFR 57.14214 - Train warnings.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Equipment Safety Practices and Operational Procedures § 57.14214 Train warnings. A warning that is audible... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Train warnings. 57.14214 Section 57.14214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL...

  18. 30 CFR 57.14214 - Train warnings.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Equipment Safety Practices and Operational Procedures § 57.14214 Train warnings. A warning that is audible... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Train warnings. 57.14214 Section 57.14214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL...

  19. 30 CFR 56.14214 - Train warnings.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Safety Practices and Operational Procedures § 56.14214 Train warnings. A warning that is audible above... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Train warnings. 56.14214 Section 56.14214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL...

  20. Periodically oscillating plasma sphere

    SciTech Connect

    Park, J.; Nebel, R.A.; Stange, S.; Murali, S. Krupakar

    2005-05-15

    The periodically oscillating plasma sphere, or POPS, is a novel fusion concept first proposed by D. C. Barnes and R. A. Nebel [Fusion Technol. 38, 28 (1998)]. POPS utilizes the self-similar collapse of an oscillating ion cloud in a spherical harmonic oscillator potential well formed by electron injection. Once the ions have been phase-locked, their coherent motion simultaneously produces very high densities and temperatures during the collapse phase of the oscillation. A requirement for POPS is that the electron injection produces a stable harmonic oscillator potential. This has been demonstrated in a gridded inertial electrostatic confinement device and verified by particle simulation. Also, the POPS oscillation has been confirmed experimentally through observation that the ions in the potential well exhibit resonance behavior when driven at the POPS frequency. Excellent agreement between the observed POPS frequencies and the theoretical predictions has been observed for a wide range of potential well depths and three different ion species. Practical applications of POPS require large plasma compressions. These large compressions have been observed in particle simulations, although space charge neutralization remains a major issue.

  1. Emergency warning systems. Part 2. Warning systems - evaluation guidelines. Final report 1982-1983

    SciTech Connect

    Tanczos, R.C.; Kanen, A.C.

    1983-07-01

    This report is the result of research performed to establish guidelines for warning systems as they are used for natural disasters, nuclear power plant accidents, or nuclear attacks. The warning systems include both fixed and mobile sirens, tone alert radios, telephone systems, power line devices. Communications systems that control these warning systems are discussed. Test results of several warning systems are included along with a discussion of sound propagation, hearing, and other items that concern the effectiveness of warning systems.

  2. 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.

  3. 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.

  4. Science off the Sphere: Bistronauts

    NASA Video Gallery

    International Space Station Expedition 30 astronaut Don Pettit demonstrates physics in space for 'Science off the Sphere.' Through a partnership between NASA and the American Physical Society you c...

  5. A survey of the status of and philosophies relating to cockpit warning systems

    NASA Technical Reports Server (NTRS)

    Cooper, G. E.

    1977-01-01

    A survey was taken to study current cockpit caution and warning (c/w) systems, and to examine industry philosophies regarding c/w system design including current efforts to improve them. Guidelines currently in use were outlined and those which appear to have general acceptance, those which are considered ineffective or erroneous, and those with which there is broad disagreement as to validity, were delineated. Major airplane manufacturerd were surveyed and a manufacturer dealing specifically with aircraft instrumentation was consulted.

  6. Microwave System for Detecting Ice on Aircraft

    NASA Technical Reports Server (NTRS)

    Joseph, Philip J.; Glynn, Dennis P., Jr.; Joseph, John C.

    2004-01-01

    A microwave-based system has been developed as a means of detecting ice on aircraft surfaces, with enough sensitivity to provide a warning before the ice accretes to a dangerous thickness. The system can measure the thickness of ice from a few mils (1 mil = 0.0254 mm) to about 1/4 in. (.6 mm) and can distinguish among (1) ice, (2) water (or deicing fluid), and (3) a mixture of ice and water (or deicing fluid). Sensors have been ruggedized to withstand the rain erosion environment.

  7. Monitoring Integrity Of Composite Aircraft Components

    NASA Technical Reports Server (NTRS)

    Tang, Shu Shing; Chen, Kuan-Luen; Kuo, An-Yu; Riccardella, Peter C.; Mucciardi, Anthony N.; Andrews, Robert J.; Grady, Joseph

    1994-01-01

    System developed that monitors integrity of composite-material structural components of aircraft in service. Includes strain gauges and accelerometers installed permanently in components to monitor vibrations, microprocessor-based data-acquisition system to process outputs of these vibration sensors, and desktop computer to analyze acquired data. By automating significant part of inspection process, system reduces amount of time needed for inspection and cost of inspection equipment. Contributes to safety by giving timely warning of hidden flaws that necessitate early, detailed inspection of critical components to determine whether components should be replaced immediately.

  8. An Unusual Rolling-Sphere Phenomenon.

    ERIC Educational Resources Information Center

    Cromer, Alan

    1996-01-01

    Discusses the theory behind a study of motion where a hollow plastic sphere racing against a steel sphere in two parallel sections of inclined channeling always reaches the bottom first; once on the floor, however, the steel sphere travels faster, speeding past the plastic sphere when both are about one meter from the base of the track. (JRH)

  9. Porous Ceramic Spheres From Cation Exchange Beads

    NASA Technical Reports Server (NTRS)

    Dynys, Fred

    2005-01-01

    This document is a slide presentation that examines the use of a simple templating process to produce hollow ceramic spheres with a pore size of 1 to 10 microns. Using ion exchange process it was determined that the method produces porous ceramic spheres with a unique structure: (i.e., inner sphere surrounded by an outer sphere.)

  10. Modeling warning times for the Israel's earthquake early warning system

    NASA Astrophysics Data System (ADS)

    Pinsky, Vladimir

    2015-01-01

    In June 2012, the Israeli government approved the offer of the creation of an earthquake early warning system (EEWS) that would provide timely alarms for schools and colleges in Israel. A network configuration was chosen, consisting of a staggered line of ˜100 stations along the main regional faults: the Dead Sea fault and the Carmel fault, and an additional ˜40 stations spread more or less evenly over the country. A hybrid approach to the EEWS alarm was suggested, where a P-wave-based system will be combined with the S-threshold method. The former utilizes first arrivals to several stations closest to the event for prompt location and determination of the earthquake's magnitude from the first 3 s of the waveform data. The latter issues alarms, when the acceleration of the surface movement exceeds a threshold for at least two neighboring stations. The threshold will be chosen to be a peak acceleration level corresponding to a magnitude 5 earthquake at a short distance range (5-10 km). The warning times or lead times, i.e., times between the alarm signal arrival and arrival of the damaging S-waves, are considered for the P, S, and hybrid EEWS methods. For each of the approaches, the P- and the S-wave travel times and the alarm times were calculated using a standard 1D velocity model and some assumptions regarding the EEWS data latencies. Then, a definition of alarm effectiveness was introduced as a measure of the trade-off between the warning time and the shaking intensity. A number of strong earthquake scenarios, together with anticipated shaking intensities at important targets, namely cities with high populations, are considered. The scenarios demonstrated in probabilistic terms how the alarm effectiveness varies depending on the target distance from the epicenter and event magnitude.

  11. Modeling warning times for the Israel's earthquake early warning system

    NASA Astrophysics Data System (ADS)

    Pinsky, Vladimir

    2014-09-01

    In June 2012, the Israeli government approved the offer of the creation of an earthquake early warning system (EEWS) that would provide timely alarms for schools and colleges in Israel. A network configuration was chosen, consisting of a staggered line of ˜100 stations along the main regional faults: the Dead Sea fault and the Carmel fault, and an additional ˜40 stations spread more or less evenly over the country. A hybrid approach to the EEWS alarm was suggested, where a P-wave-based system will be combined with the S-threshold method. The former utilizes first arrivals to several stations closest to the event for prompt location and determination of the earthquake's magnitude from the first 3 s of the waveform data. The latter issues alarms, when the acceleration of the surface movement exceeds a threshold for at least two neighboring stations. The threshold will be chosen to be a peak acceleration level corresponding to a magnitude 5 earthquake at a short distance range (5-10 km). The warning times or lead times, i.e., times between the alarm signal arrival and arrival of the damaging S-waves, are considered for the P, S, and hybrid EEWS methods. For each of the approaches, the P- and the S-wave travel times and the alarm times were calculated using a standard 1D velocity model and some assumptions regarding the EEWS data latencies. Then, a definition of alarm effectiveness was introduced as a measure of the trade-off between the warning time and the shaking intensity. A number of strong earthquake scenarios, together with anticipated shaking intensities at important targets, namely cities with high populations, are considered. The scenarios demonstrated in probabilistic terms how the alarm effectiveness varies depending on the target distance from the epicenter and event magnitude.

  12. SC-228 Inclusion of DAA Warning Alert for TCAS Interoperability

    NASA Technical Reports Server (NTRS)

    Fern, Lisa

    2016-01-01

    This white paper summarizes NASA research results that have informed Special Committee 228 (SC-228) discussions and decisions regarding the inclusion of a warning-level alert within the detect and avoid (DAA) alerting structure for unmanned aircraft systems (UAS). For UAS, the removal of the pilot from onboard the aircraft has eliminated the ability of the ground-based pilot in command (PIC) to use out-the-window visual information to make judgments about a potential threat of a loss of well clear with another aircraft. As a result, the DAA traffic display will be the primary source of information that the PIC can use to execute the three primary well clear functions: 1) detect a potential loss of well clear, 2) determine a resolution maneuver, and 3) upload that maneuver to the aircraft via the ground control station (GCS). In addition, pilots are required to coordinate with air traffic control (ATC) prior to maneuvering off of their approved flight plan. In determining an appropriate resolution maneuver to avoid a loss of well clear, the PIC must decide both when and how to maneuver, and both the timeliness and the accuracy (i.e., correctness) of the maneuver are critical to reducing the likelihood and/or severity of a loss of well clear. Alerting information is one of three critical components of the DAA display, along with traffic information elements (e.g., relative heading, speed and altitude) and maneuver guidance. Alerting information and maneuver guidance, in particular, have been found to have a significant impact, both statistically and practically, on pilots' ability to avoid and minimize the severity of losses of well clear While all three display components are key to pilots performing the traffic avoidance task of remaining well clear, in general, alerting information provides crucial information about when a resolution maneuver is required while maneuver guidance assists the pilot in determining how best to maneuver. A fundamental task of the DAA

  13. 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.

  14. ForWarn Forest Disturbance Change Detection System Provides a Weekly Snapshot of US Forest Conditions to Aid Forest Managers

    NASA Astrophysics Data System (ADS)

    Hargrove, W. W.; Spruce, J.; Kumar, J.; Hoffman, F. M.

    2012-12-01

    The Eastern Forest Environmental Threat Assessment Center and Western Wildland Environmental Assessment Center of the USDA Forest Service have collaborated with NASA Stennis Space Center to develop ForWarn, a forest monitoring tool that uses MODIS satellite imagery to produce weekly snapshots of vegetation conditions across the lower 48 United States. Forest and natural resource managers can use ForWarn to rapidly detect, identify, and respond to unexpected changes in the nation's forests caused by insects, diseases, wildfires, severe weather, or other natural or human-caused events. ForWarn detects most types of forest disturbances, including insects, disease, wildfires, frost and ice damage, tornadoes, hurricanes, blowdowns, harvest, urbanization, and landslides. It also detects drought, flood, and temperature effects, and shows early and delayed seasonal vegetation development. Operating continuously since January 2010, results show ForWarn to be a robust and highly capable tool for detecting changes in forest conditions. To help forest and natural resource managers rapidly detect, identify, and respond to unexpected changes in the nation's forests, ForWarn produces sets of national maps showing potential forest disturbances at 231m resolution every 8 days, and posts the results to the web for examination. ForWarn compares current greenness with the "normal," historically seen greenness that would be expected for healthy vegetation for a specific location and time of the year, and then identifies areas appearing less green than expected to provide a strategic national overview of potential forest disturbances that can be used to direct ground and aircraft efforts. In addition to forests, ForWarn also tracks potential disturbances in rangeland vegetation and agriculural crops. ForWarn is the first national-scale system of its kind based on remote sensing developed specifically for forest disturbances. The ForWarn system had an official unveiling and rollout in

  15. The warning glove - development and evaluation of a multimodal action-specific warning prototype.

    PubMed

    Schmuntzsch, Ulrike; Sturm, Christine; Roetting, Matthias

    2014-09-01

    This paper has two objectives: first, to introduce the concept of multimodal action-specific warnings and its prototypic realization in the form of a warning glove and second, to present the main findings of a user study that was conducted to test the warning glove against a conventional warning system. Regarding the first goal, the combination of multimodality and action-specificity was implemented by attaching electronic actuators on a right-handed glove for transmitting visual, auditory and tactile feedback. For the second objective, a user study was conducted to test the hypothesis that the warning glove is capable of obtaining faster responses and to determine the perceptions of the users regarding the appropriateness of the warning glove. The results confirmed the assumption of faster response times and participants perceived the warning glove to be 'fairly appropriate'. These results warrant further development of this multimodal action-specific warning glove.

  16. A Personal Storm Warning Service

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Although lightning detection systems operated by government agencies, utilities and other businesses provide storm warnings, this information often does not reach the public until some time after the observations have been made. A low-cost personal lightning detector offers a significant safety advantage to private flyers, boaters, golfers and others. Developed by Airborne Research Associates, the detectors originated in Space Shuttle tests of an optical lightning detection technique. The commercial device is pointed toward a cloud to detect invisible intracloud lightning by sensing subtle changes in light presence. The majority of the sales have been to golf courses. Additional products and more advanced applications are in progress.

  17. Communicating risk information and warnings

    USGS Publications Warehouse

    Mileti, D. S.

    1990-01-01

    Major advances have occurred over the last 20 years about how to effectively communicate risk information and warnings to the public. These lessons have been hard won. Knowledge has mounted on the finding from social scientific studies of risk communication failures, successes and those which fell somewhere in between. Moreover, the last 2 decades have borne witness to the brith, cultivation, and blossoming of information sharing between those physical scientists who discover new information about risk and those communcation scientists who trace its diffusion and then measure pbulic reaction. 

  18. Sphere forming method and apparatus

    NASA Technical Reports Server (NTRS)

    Youngberg, C. L.; Miller, C. G.; Stephens, J. B.; Finnerty, A. A. (Inventor)

    1983-01-01

    A system is provided for forming small accurately spherical objects. Preformed largely spherical objects are supported at the opening of a conduit on the update of hot gas emitted from the opening, so the object is in a molten state. The conduit is suddenly jerked away at a downward incline, to allow the molten object to drop in free fall, so that surface tension forms a precise sphere. The conduit portion that has the opening, lies in a moderate vacuum chamber, and the falling sphere passes through the chamber and through a briefly opened valve into a tall drop tower that contains a lower pressure, to allow the sphere to cool without deformation caused by falling through air.

  19. 33 CFR 127.113 - Warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas § 127.113 Warning signs. (a) The marine transfer...

  20. 33 CFR 127.113 - Warning signs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas § 127.113 Warning signs. (a) The marine transfer...

  1. 33 CFR 127.113 - Warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas § 127.113 Warning signs. (a) The marine transfer...

  2. 33 CFR 127.113 - Warning signs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas § 127.113 Warning signs. (a) The marine transfer...

  3. 33 CFR 127.207 - Warning alarms.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas Equipment § 127.207 Warning alarms. (a) The...

  4. 33 CFR 127.113 - Warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas § 127.113 Warning signs. (a) The marine transfer...

  5. A Real-Time Advisory System For Airborne Early Warning

    NASA Astrophysics Data System (ADS)

    Kirk, D. B.; Cromwell, M. E.; Donnell, M. L.; Barrett, C. L.

    1987-05-01

    Decision speed and quality can be greatly enhanced by the use of decision augmentation software to assist operators in information analysis and tactical problem solving, dynamic resource allocation, and in determining strategies which optimize overall system performance. One example of such software is the real-time advisory system (RTAS) being constructed to assist in tactical decision-making for airborne early warning (AEW) aircraft, particularly the carrier-based Navy E-2C. Using a vector logic approach, the current AEW RTAS is a real-time backward chaining expert system which provides advice for both threat interception and refueling in the complex Outer Air Battle Scenario. This paper describes the current system, discusses a number of design issues for such a system, and describes ongoing modifications to the current AEW RTAS using SAIC's frame-based knowledge repre-sentation language (KRL).

  6. Human Response to Emergency Warning

    NASA Astrophysics Data System (ADS)

    Sorensen, J.

    2009-12-01

    Almost every day people evacuate from their homes, businesses or other sites, even ships, in response to actual or predicted threats or hazards. Evacuation is the primary protective action utilized in large-scale emergencies such as hurricanes, floods, tornados, tsunamis, volcanic eruptions, or wildfires. Although often precautionary, protecting human lives by temporally relocating populations before or during times of threat remains a major emergency management strategy. One of the most formidable challenges facing emergency officials is evacuating residents for a fast-moving and largely unpredictable event such as a wildfire or a local tsunami. How to issue effective warnings to those at risk in time for residents to take appropriate action is an on-going problem. To do so, some communities have instituted advanced communications systems that include reverse telephone call-down systems or other alerting systems to notify at-risk residents of imminent threats. This presentation examines the effectiveness of using reverse telephone call-down systems for warning San Diego residents of wildfires in the October of 2007. This is the first systematic study conducted on this topic and is based on interviews with 1200 households in the evacuation areas.

  7. The Effect of Sonic Booms on Earthquake Warning Systems

    NASA Technical Reports Server (NTRS)

    Wurman, Gilead; Haering, Edward A, Jr.; Price, Michael J.

    2011-01-01

    Several aerospace companies are designing quiet supersonic business jets for service over the United States. These aircraft have the potential to increase the occurrence of mild sonic booms across the country. This leads to interest among earthquake warning (EQW) developers and the general seismological community in characterizing the effect of sonic booms on seismic sensors in the field, their potential impact on EQW systems, and means of discriminating their signatures from those of earthquakes. The SonicBREWS project (Sonic Boom Resistant Earthquake Warning Systems) is a collaborative effort between Seismic Warning Systems, Inc. (SWS) and NASA Dryden Flight Research Center. This project aims to evaluate the effects of sonic booms on EQW sensors. The study consists of exposing high-sample-rate (1000 sps) triaxial accelerometers to sonic booms with overpressures ranging from 10 to 600 Pa in the free field and the built environment. The accelerometers record the coupling of the sonic boom to the ground and surrounding structures, while microphones record the acoustic wave above ground near the sensor. Sonic booms are broadband signals with more high-frequency content than earthquakes. Even a 1000 sps accelerometer will produce a significantly aliased record. Thus the observed peak ground velocity is strongly dependent on the sampling rate, and increases as the sampling rate is reduced. At 1000 sps we observe ground velocities that exceed those of P-waves from ML 3 earthquakes at local distances, suggesting that sonic booms are not negligible for EQW applications. We present the results of several experiments conducted under SonicBREWS showing the effects of typical-case low amplitude sonic booms and worst-case high amplitude booms. We show the effects of various sensor placements and sensor array geometries. Finally, we suggest possible avenues for discriminating sonic booms from earthquakes for the purposes of EQW.

  8. 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...

  9. 21 CFR 1141.10 - Required warnings.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... PRODUCTS CIGARETTE PACKAGE AND ADVERTISING WARNINGS; (Eff. 9-22-12) Cigarette Package and Advertising... cigarettes the package of which fails to bear, in accordance with section 4 of the Federal Cigarette Labeling... “Cigarette Required Warnings,” which is incorporated by reference at § 1141.12, and accurately reproduced...

  10. 21 CFR 1141.10 - Required warnings.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... PRODUCTS CIGARETTE PACKAGE AND ADVERTISING WARNINGS Cigarette Package and Advertising Warnings § 1141.10..., offer to sell, distribute, or import for sale or distribution within the United States any cigarettes the package of which fails to bear, in accordance with section 4 of the Federal Cigarette Labeling...

  11. Volcanic hazard warning system: Persistence and transferability

    NASA Astrophysics Data System (ADS)

    Sorensen, John H.; Gersmehl, Philip J.

    1980-03-01

    This study examines the normative functioning of the volcano warning system on the Island of Hawaii. The research seeks to identify the combination of factors, both environmental and social, which allows the system to operate with success. On the basis of the findings, several recommendations are offered for improving environmental hazard warning systems.

  12. 21 CFR 1141.10 - Required warnings.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... PRODUCTS CIGARETTE PACKAGE AND ADVERTISING WARNINGS Cigarette Package and Advertising Warnings § 1141.10..., offer to sell, distribute, or import for sale or distribution within the United States any cigarettes the package of which fails to bear, in accordance with section 4 of the Federal Cigarette Labeling...

  13. Urban Flood Warning Systems using Radar Technologies

    NASA Astrophysics Data System (ADS)

    Fang, N.; Bedient, P. B.

    2013-12-01

    There have been an increasing number of urban areas that rely on weather radars to provide accurate precipitation information for flood warning purposes. As non-structural tools, radar-based flood warning systems can provide accurate and timely warnings to the public and private entities in urban areas that are prone to flash floods. The wider spatial and temporal coverage from radar increases flood warning lead-time when compared to rain and stream gages alone. The Third Generation Rice and Texas Medical Center (TMC) Flood Alert System (FAS3) has been delivering warning information with 2 to 3 hours of lead time and a R2 value of 93% to facility personnel in a readily understood format for more than 50 events in the past 15 years. The current FAS utilizes NEXRAD Level II radar rainfall data coupled with a real-time hydrologic model (RTHEC-1) to deliver warning information. The system has a user-friendly dashboard to provide rainfall maps, Google Maps based inundation maps, hydrologic predictions, and real-time monitoring at the bayou. This paper will evaluate its reliable performance during the recent events occurring in 2012 and 2013 and the development of a similar radar-based flood warning system for the City of Sugar Land, Texas. Having a significant role in the communication of flood information, FAS marks an important step towards the establishment of an operational and reliable flood warning system for flood-prone urban areas.

  14. 24 CFR 200.1505 - Warning letter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... URBAN DEVELOPMENT GENERAL INTRODUCTION TO FHA PROGRAMS Multifamily Accelerated Processing (MAP): MAP... letter, which specifies problems or violations identified by HUD, to a MAP lender. (b) Effect of warning letter. The warning letter: (1) Does not suspend a lender's MAP privileges; (2) May impose a higher...

  15. 49 CFR 229.113 - Warning notice.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Steam Generators § 229.113 Warning notice. Whenever any steam generator has been shut down because of defects, a distinctive warning notice giving reasons for the shut-down shall be conspicuously attached near the steam...

  16. 49 CFR 229.113 - Warning notice.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Steam Generators § 229.113 Warning notice. Whenever any steam generator has been shut down because of defects, a distinctive warning notice giving reasons for the shut-down shall be conspicuously attached near the steam...

  17. 49 CFR 229.113 - Warning notice.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Steam Generators § 229.113 Warning notice. Whenever any steam generator has been shut down because of defects, a distinctive warning notice giving reasons for the shut-down shall be conspicuously attached near the steam...

  18. 49 CFR 229.113 - Warning notice.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Steam Generators § 229.113 Warning notice. Whenever any steam generator has been shut down because of defects, a distinctive warning notice giving reasons for the shut-down shall be conspicuously attached near the steam...

  19. 49 CFR 229.113 - Warning notice.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Steam Generators § 229.113 Warning notice. Whenever any steam generator has been shut down because of defects, a distinctive warning notice giving reasons for the shut-down shall be conspicuously attached near the steam...

  20. 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.

  1. Reducing online identity disclosure using warnings.

    PubMed

    Carpenter, Sandra; Zhu, Feng; Kolimi, Swapna

    2014-09-01

    In an experimental design, we tested whether written warnings can reduce the amount of identity information exposure online. A psychological attack on information privacy that has been shown to be effective in previous research was launched. This attack took advantage of the fact that people respond to certain types of requests in a relatively automatic, or mindless, fashion. The experiment manipulated the word that was used in the alert header: "warning", "caution", or "hazard". All warnings proved to be effective in reducing disclosure, but "hazard" proved to be most effective. Also warnings were more effective in reducing disclosure of driver's license numbers than email addresses. The discussion (a) provides tentative conclusions why these patterns were obtained, (b) suggests how to design warnings in cyber-environments, and (c) addresses future possibilities for research on this topic. PMID:24161300

  2. Expert-recommended warnings for medical marijuana.

    PubMed

    Malouff, John M; Rooke, Sally E

    2013-01-01

    Medical marijuana is legal in some countries, including in many US states. At present, there are no government-mandated warnings on packages of marijuana, even though the substance has dangers similar to those of alcohol, tobacco, and various prescribed drugs. This article reports the results of an effort to collect marijuana warnings recommended by scientific experts on marijuana. The recommended warnings, the first ever from marijuana experts, come from 13 experts. The expert-recommended warnings pertain to risks relating to (1) safety, (2) physical health, (3) fetal harm, (4) mental health, (5) withdrawal and dependence, and (6) adolescent development. The results provide initial expert recommendations for warnings to be required on packages of medical marijuana.

  3. Reducing online identity disclosure using warnings.

    PubMed

    Carpenter, Sandra; Zhu, Feng; Kolimi, Swapna

    2014-09-01

    In an experimental design, we tested whether written warnings can reduce the amount of identity information exposure online. A psychological attack on information privacy that has been shown to be effective in previous research was launched. This attack took advantage of the fact that people respond to certain types of requests in a relatively automatic, or mindless, fashion. The experiment manipulated the word that was used in the alert header: "warning", "caution", or "hazard". All warnings proved to be effective in reducing disclosure, but "hazard" proved to be most effective. Also warnings were more effective in reducing disclosure of driver's license numbers than email addresses. The discussion (a) provides tentative conclusions why these patterns were obtained, (b) suggests how to design warnings in cyber-environments, and (c) addresses future possibilities for research on this topic.

  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. Science off the Sphere: Fun with Antibubbles

    NASA Video Gallery

    International Space Station Expedition 30 astronaut Don Pettit injects air bubbles inside a sphere of water to demonstrate physics in space for 'Science off the Sphere.' Through a partnership betwe...

  6. Tessellating the Sphere with Regular Polygons

    ERIC Educational Resources Information Center

    Soto-Johnson, Hortensia; Bechthold, Dawn

    2004-01-01

    Tessellations in the Euclidean plane and regular polygons that tessellate the sphere are reviewed. The regular polygons that can possibly tesellate the sphere are spherical triangles, squares and pentagons.

  7. Eddy currents in a conducting sphere

    NASA Technical Reports Server (NTRS)

    Bergman, John; Hestenes, David

    1986-01-01

    This report analyzes the eddy current induced in a solid conducting sphere by a sinusoidal current in a circular loop. Analytical expressions for the eddy currents are derived as a power series in the vectorial displacement of the center of the sphere from the axis of the loop. These are used for first order calculations of the power dissipated in the sphere and the force and torque exerted on the sphere by the electromagnetic field of the loop.

  8. Active swarms on a sphere.

    PubMed

    Sknepnek, Rastko; Henkes, Silke

    2015-02-01

    We show that coupling to curvature nontrivially affects collective motion in active systems, leading to motion patterns not observed in flat space. Using numerical simulations, we study a model of self-propelled particles with polar alignment and soft repulsion confined to move on the surface of a sphere. We observe a variety of motion patterns with the main hallmarks being polar vortex and circulating band states arising due to the incompatibility between spherical topology and uniform motion-a consequence of the "hairy ball" theorem. We provide a detailed analysis of density, velocity, pressure, and stress profiles in the circulating band state. In addition, we present analytical results for a simplified model of collective motion on the sphere showing that frustration due to curvature leads to stable elastic distortions storing energy in the band. PMID:25768504

  9. Active swarms on a sphere.

    PubMed

    Sknepnek, Rastko; Henkes, Silke

    2015-02-01

    We show that coupling to curvature nontrivially affects collective motion in active systems, leading to motion patterns not observed in flat space. Using numerical simulations, we study a model of self-propelled particles with polar alignment and soft repulsion confined to move on the surface of a sphere. We observe a variety of motion patterns with the main hallmarks being polar vortex and circulating band states arising due to the incompatibility between spherical topology and uniform motion-a consequence of the "hairy ball" theorem. We provide a detailed analysis of density, velocity, pressure, and stress profiles in the circulating band state. In addition, we present analytical results for a simplified model of collective motion on the sphere showing that frustration due to curvature leads to stable elastic distortions storing energy in the band.

  10. Vortical flow past a sphere

    NASA Astrophysics Data System (ADS)

    Mattner, Trent; Chong, Min; Joubert, Peter

    2000-11-01

    Vortical flow past a sphere in a constant diameter pipe was studied experimentally in a guide vane apparatus similar to those used in fundamental experimental studies of vortex breakdown. The initial effect of swirl was to shorten the downstream separation bubble. For a small range of the swirl intensity, an almost stagnant upstream separation bubble formed. As the swirl intensity was increased, the bubble became unstable and an unsteady spiral formed. At high swirl intensity there was a mean recirculation region which penetrated far upstream while the flow on the downstream hemisphere was attached. Measurements of the velocity field were obtained using laser Doppler velocimetry. Analysis of these results suggests that the onset of upstream separation is associated with the formation of a negative azimuthal vorticity component which slows the axial flow near the axis of symmetry. This is consistent with inviscid distortion of the vortex filaments in the diverging flow approaching the sphere.

  11. Archaic artifacts resembling celestial spheres

    NASA Astrophysics Data System (ADS)

    Dimitrakoudis, S.; Papaspyrou, P.; Petoussis, V.; Moussas, X.

    We present several bronze artifacts from the Archaic Age in Greece (750-480 BC) that resemble celestial spheres or forms of other astronomical significance. They are studied in the context of the Dark Age transition from Mycenaean Age astronomical themes to the philosophical and practical revival of astronomy in the Classical Age with its plethora of astronomical devices. These artifacts, mostly votive in nature are spherical in shape and appear in a variety of forms their most striking characteristic being the depiction of meridians and/or an equator. Most of those artifacts come from Thessaly, and more specifically from the temple of Itonia Athena at Philia, a religious center of pan-Hellenic significance. Celestial spheres, similar in form to the small artifacts presented in this study, could be used to measure latitudes, or estimate the time at a known place, and were thus very useful in navigation.

  12. Experimental context modulates warning signal effects.

    PubMed

    Machado-Pinheiro, W; Faria, A J P; Gawryszewski, L G; Ribeiro-do-Valle, L E

    2004-07-01

    Previous studies have shown that saccadic eye responses but not manual responses were sensitive to the kind of warning signal used, with visual onsets producing longer saccadic latencies compared to visual offsets. The aim of the present study was to determine the effects of distinct warning signals on manual latencies and to test the premise that the onset interference, in fact, does not occur for manual responses. A second objective was to determine if the magnitude of the warning effects could be modulated by contextual procedures. Three experimental conditions based on the kind of warning signal used (visual onset, visual offset and auditory warning) were run in two different contexts (blocked and non-blocked). Eighteen participants were asked to respond to the imperative stimulus that would occur some milliseconds (0, 250, 500 or 750 ms) after the warning signal. The experiment consisted in three experimental sessions of 240 trials, where all the variables were counterbalanced. The data showed that visual onsets produced longer manual latencies than visual offsets in the non-blocked context (275 vs 261 ms; P < 0.001). This interference was obtained, however, only for short intervals between the warning and the stimulus, and was abolished when the blocked context was used (256 vs 255 ms; P = 0.789). These results are discussed in terms of bottom-up and top-down interactions, mainly those related to the role of attentional processing in cancelling out competitive interactions and suppressive influences of a distractor on the relevant stimulus.

  13. Numerical simulation of a sphere moving down an incline with identical spheres placed equally apart

    USGS Publications Warehouse

    Ling, Chi-Hai; Jan, Chyan-Deng; Chen, Cheng-lung; Shen, Hsieh Wen

    1992-01-01

    This paper describes a numerical study of an elastic sphere moving down an incline with a string of identical spheres placed equally apart. Two momentum equations and a moment equation formulated for the moving sphere are solved numerically for the instantaneous velocity of the moving sphere on an incline with different angles of inclination. Input parameters for numerical simulation include the properties of the sphere (the radius, density, Poison's ratio, and Young's Modulus of elasticity), the coefficient of friction between the spheres, and a damping coefficient of the spheres during collision.

  14. Underwater implosion of glass spheres.

    PubMed

    Turner, Stephen E

    2007-02-01

    Underwater implosion experiments were conducted with thin-wall glass spheres to determine the influence that structural failure has on the pressure pulse. Four experiments were conducted with glass spheres having an outside diameter of 7.62 cm, thickness of 0.762 mm, and an estimated buckling pressure of 7.57 MPa. The experiments were performed in a pressure vessel at a hydrostatic pressure of 6.996 MPa. The average peak pressure of the implosion pressure pulse was 26.1 MPa, measured at a radial distance of 10.16 cm from the sphere center. A computational fluid structure interaction model was developed to assess how the failure rate of the glass structure influences the pressure time history. The model employed a specified glass failure sequence that is uniform in time and space. It was found that for the conditions of the test, a glass failure rate of 275 m/s provided a reasonable representation of the test data. The test data and the model results show that the failure time history of the structure has a significant influence on an implosion pressure pulse. Computational prediction of an implosion pressure pulse needs to include the failure time history of the structure; otherwise it will overpredict the pressure time history.

  15. Continuous measurement of aircraft wing icing

    NASA Technical Reports Server (NTRS)

    Yao, Stephen S. C.

    1994-01-01

    Ice formation on the wings of aircraft is a problem that has plagued air travel since its inception. Several recent incidents have been attributed to ice formation on the lifting surfaces of wings. This paper describes a SBIR Phase 1 research effort on the use of small flat dielectric sensors in detecting a layer of ice above the sensor. The sensors are very small, lightweight, and inexpensive. The electronics package that controls the sensor is also small, and could be even smaller using commonly available miniaturization technologies. Thus, several sensors could be placed on a surface such that a representative ice thickness profile could be measured. The benefits offered by developing this technology go beyond the safety improvements realized by monitoring ice formation on the wings of an aircraft. Continuous monitoring of anti-icing fluid concentrations on the ground would warn the pilot of impending fluid failure as well as allowing the stations to use less de-icing solution per aircraft. This in turn would increase the safety of takeoffs and reduce the overall discharge of de-icing solution into the environment, thus reducing the biohazard of the de-icing procedure.

  16. Raptors and aircraft

    USGS Publications Warehouse

    Smith, D.G.; Ellis, D.H.; Johnson, T.H.; Glinski, Richard L.; Pendleton, Beth Giron; Moss, Mary Beth; LeFranc, Maurice N.=; Millsap, Brian A.; Hoffman, Stephen W.

    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.

  17. Generating perfect fluid spheres in general relativity

    NASA Astrophysics Data System (ADS)

    Boonserm, Petarpa; Visser, Matt; Weinfurtner, Silke

    2005-06-01

    Ever since Karl Schwarzschild’s 1916 discovery of the spacetime geometry describing the interior of a particular idealized general relativistic star—a static spherically symmetric blob of fluid with position-independent density—the general relativity community has continued to devote considerable time and energy to understanding the general-relativistic static perfect fluid sphere. Over the last 90 years a tangle of specific perfect fluid spheres has been discovered, with most of these specific examples seemingly independent from each other. To bring some order to this collection, in this article we develop several new transformation theorems that map perfect fluid spheres into perfect fluid spheres. These transformation theorems sometimes lead to unexpected connections between previously known perfect fluid spheres, sometimes lead to new previously unknown perfect fluid spheres, and in general can be used to develop a systematic way of classifying the set of all perfect fluid spheres.

  18. A novel three-dimensional mesh deformation method based on sphere relaxation

    SciTech Connect

    Zhou, Xuan; Li, Shuixiang

    2015-10-01

    In our previous work (2013) [19], we developed a disk relaxation based mesh deformation method for two-dimensional mesh deformation. In this paper, the idea of the disk relaxation is extended to the sphere relaxation for three-dimensional meshes with large deformations. We develop a node based pre-displacement procedure to apply initial movements on nodes according to their layer indices. Afterwards, the nodes are moved locally by the improved sphere relaxation algorithm to transfer boundary deformations and increase the mesh quality. A three-dimensional mesh smoothing method is also adopted to prevent the occurrence of the negative volume of elements, and further improve the mesh quality. Numerical applications in three-dimension including the wing rotation, bending beam and morphing aircraft are carried out. The results demonstrate that the sphere relaxation based approach generates the deformed mesh with high quality, especially regarding complex boundaries and large deformations.

  19. 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.

  20. 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.

  1. 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.

  2. Application of a Tsunami Warning Message Metric to refine NOAA NWS Tsunami Warning Messages

    NASA Astrophysics Data System (ADS)

    Gregg, C. E.; Johnston, D.; Sorensen, J.; Whitmore, P.

    2013-12-01

    In 2010, the U.S. National Weather Service (NWS) funded a three year project to integrate social science into their Tsunami Program. One of three primary requirements of the grant was to make improvements to tsunami warning messages of the NWS' two Tsunami Warning Centers- the West Coast/Alaska Tsunami Warning Center (WCATWC) in Palmer, Alaska and the Pacific Tsunami Warning Center (PTWC) in Ewa Beach, Hawaii. We conducted focus group meetings with a purposive sample of local, state and Federal stakeholders and emergency managers in six states (AK, WA, OR, CA, HI and NC) and two US Territories (US Virgin Islands and American Samoa) to qualitatively asses information needs in tsunami warning messages using WCATWC tsunami messages for the March 2011 Tohoku earthquake and tsunami event. We also reviewed research literature on behavioral response to warnings to develop a tsunami warning message metric that could be used to guide revisions to tsunami warning messages of both warning centers. The message metric is divided into categories of Message Content, Style, Order and Formatting and Receiver Characteristics. A message is evaluated by cross-referencing the message with the operational definitions of metric factors. Findings are then used to guide revisions of the message until the characteristics of each factor are met. Using findings from this project and findings from a parallel NWS Warning Tiger Team study led by T. Nicolini, the WCATWC implemented the first of two phases of revisions to their warning messages in November 2012. A second phase of additional changes, which will fully implement the redesign of messages based on the metric, is in progress. The resulting messages will reflect current state-of-the-art knowledge on warning message effectiveness. Here we present the message metric; evidence-based rational for message factors; and examples of previous, existing and proposed messages.

  3. 33 CFR 127.1113 - Warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... section, bear the following text: Warning Dangerous Cargo No visitors No Smoking No Open Lights (b) Each... centimeters (3 inches) high. (c) The words “No Smoking” and “No Open Lights” may be omitted when the...

  4. 33 CFR 127.1113 - Warning signs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... section, bear the following text: Warning Dangerous Cargo No visitors No Smoking No Open Lights (b) Each... centimeters (3 inches) high. (c) The words “No Smoking” and “No Open Lights” may be omitted when the...

  5. 33 CFR 127.1113 - Warning signs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... section, bear the following text: Warning Dangerous Cargo No visitors No Smoking No Open Lights (b) Each... centimeters (3 inches) high. (c) The words “No Smoking” and “No Open Lights” may be omitted when the...

  6. 33 CFR 127.1113 - Warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... section, bear the following text: Warning Dangerous Cargo No visitors No Smoking No Open Lights (b) Each... centimeters (3 inches) high. (c) The words “No Smoking” and “No Open Lights” may be omitted when the...

  7. 33 CFR 127.1113 - Warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... section, bear the following text: Warning Dangerous Cargo No visitors No Smoking No Open Lights (b) Each... centimeters (3 inches) high. (c) The words “No Smoking” and “No Open Lights” may be omitted when the...

  8. FDA Warns About Stem Cell Claims

    MedlinePlus

    ... Home For Consumers Consumer Updates FDA Warns About Stem Cell Claims Share Tweet Linkedin Pin it More sharing ... blood-forming system. back to top Regulation of Stem Cells FDA regulates stem cells in the U.S. to ...

  9. Warning signs and symptoms of heart disease

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000775.htm Warning signs and symptoms of heart disease To use the ... often develops over time. You may have early signs or symptoms long before you have serious heart ...

  10. FDA Warns Ovarian Cancer Tests Not Reliable

    MedlinePlus

    ... medlineplus.gov/news/fullstory_160880.html FDA Warns Ovarian Cancer Tests Not Reliable May delay preventive therapies for ... Sept. 9, 2016 (HealthDay News) -- Screening tests for ovarian cancer are not reliable and should not be used, ...

  11. 40 CFR 763.95 - Warning labels.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT ASBESTOS Asbestos-Containing Materials in Schools § 763.95 Warning labels. (a) The local education agency shall...: ASBESTOS. HAZARDOUS. DO NOT DISTURB WITHOUT PROPER TRAINING AND EQUIPMENT....

  12. 40 CFR 763.95 - Warning labels.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT ASBESTOS Asbestos-Containing Materials in Schools § 763.95 Warning labels. (a) The local education agency shall...: ASBESTOS. HAZARDOUS. DO NOT DISTURB WITHOUT PROPER TRAINING AND EQUIPMENT....

  13. 40 CFR 763.95 - Warning labels.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT ASBESTOS Asbestos-Containing Materials in Schools § 763.95 Warning labels. (a) The local education agency shall...: ASBESTOS. HAZARDOUS. DO NOT DISTURB WITHOUT PROPER TRAINING AND EQUIPMENT....

  14. 40 CFR 763.95 - Warning labels.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT ASBESTOS Asbestos-Containing Materials in Schools § 763.95 Warning labels. (a) The local education agency shall...: ASBESTOS. HAZARDOUS. DO NOT DISTURB WITHOUT PROPER TRAINING AND EQUIPMENT....

  15. An Early Warning System for Flounder Disease

    NASA Astrophysics Data System (ADS)

    Xing, Bin; Li, Daoliang; Wang, Jianqin; Duan, Qingling; Wen, Jiwen

    With the constant expansion of the scale and mismanagement in aquaculture,the diseases of flounder occur more and more frequently than before, which has brought great economic losses to fish farmers. For the sake of the problem described above, based on a great number of surveys, the early warning theory of flounder disease, the analysis of the outbreak and development of diseases and the relationship between disease and factors, the logic process of the early warning for flounder disease was confirmed. It consists of five parts: specifying the target, searching for the source, distinguishing the sign, predicting the degree and eliminating the menace. Using the expert survey method the early warning indexes which affect the normal life of the flounder and calculated the range of the water environment factors were also confirmed. Finally, an early warning system was implemented, which can reduce the damage from the flounder disease.

  16. Meteorological Monitoring And Warning Computer Network

    NASA Technical Reports Server (NTRS)

    Evans, Randolph J.; Dianic, Allan V.; Moore, Lien N.

    1996-01-01

    Meteorological monitoring system (MMS) computer network tracks weather conditions and issues warnings when weather hazards are about to occur. Receives data from such meteorological instruments as wind sensors on towers and lightning detectors, and compares data with weather restrictions specified for outdoor activities. If weather violates restriction, network generates audible and visible alarms to alert people involved in activity. Also displays weather and toxic diffusion data and disseminates weather forecasts, advisories, and warnings to workstations.

  17. Health warnings on tobacco products: international practices.

    PubMed

    Hammond, David; Reid, Jessica L

    2012-06-01

    Health warnings on tobacco products have emerged as a prominent area of tobacco control policy. Regulatory practice has rapidly evolved over the past decade to the point where health warnings on tobacco products continue to set international precedents for their size and comprehensiveness. The current paper provides a general review of current regulatory practices, including physical design features (such as size and location), message content (pictorial vs. text and content themes), and regulatory considerations such as rotation period and other novel practices.

  18. Novelty effects in a multimodal warning signal.

    PubMed

    Rowe; Guilford

    1999-02-01

    The warning signals of toxic insects are often 'multimodal', combining bright coloration with sounds or odours (or both). Pyrazine (a common insect warning odour) can elicit an intrinsic avoidance in domestic chicks Gallus gallus domesticus, both against novel coloured food, and also against food colours that are specifically associated with aposematism, namely yellow and red. In three experiments, we investigated the role of novelty in this innate bias against yellow coloured food in the presence of pyrazine. Naive chicks were familiarized either to pyrazine odour or to coloured food before being tested for a bias against yellow (warningly coloured) food as opposed to green (nonwarningly coloured) food. In experiment 1, pyrazine novelty was shown to be vital for eliciting a bias against yellow food. However, experiment 2 suggested that colour novelty was not important: chicks familiarized with coloured crumbs still avoided yellow crumbs when pyrazine was presented. In a third experiment that gave chicks an even greater degree of pre-exposure to coloured crumbs, the bias against yellow food eventually waned, although pyrazine continued to elicit an aversion to yellow even after birds had had experience of up to 24 palatable yellow crumbs. Pyrazine novelty has been an important pressure in the evolution of multimodal warning signals, and can continue to promote the avoidance of warningly coloured food, even when it is relatively familiar. The implications for warning signals are discussed. Copyright 1999 The Association for the Study of Animal Behaviour.

  19. Evolution of tsunami warning systems and products.

    PubMed

    Bernard, Eddie; Titov, Vasily

    2015-10-28

    Each year, about 60 000 people and $4 billion (US$) in assets are exposed to the global tsunami hazard. Accurate and reliable tsunami warning systems have been shown to provide a significant defence for this flooding hazard. However, the evolution of warning systems has been influenced by two processes: deadly tsunamis and available technology. In this paper, we explore the evolution of science and technology used in tsunami warning systems, the evolution of their products using warning technologies, and offer suggestions for a new generation of warning products, aimed at the flooding nature of the hazard, to reduce future tsunami impacts on society. We conclude that coastal communities would be well served by receiving three standardized, accurate, real-time tsunami warning products, namely (i) tsunami energy estimate, (ii) flooding maps and (iii) tsunami-induced harbour current maps to minimize the impact of tsunamis. Such information would arm communities with vital flooding guidance for evacuations and port operations. The advantage of global standardized flooding products delivered in a common format is efficiency and accuracy, which leads to effectiveness in promoting tsunami resilience at the community level.

  20. Evolution of tsunami warning systems and products.

    PubMed

    Bernard, Eddie; Titov, Vasily

    2015-10-28

    Each year, about 60 000 people and $4 billion (US$) in assets are exposed to the global tsunami hazard. Accurate and reliable tsunami warning systems have been shown to provide a significant defence for this flooding hazard. However, the evolution of warning systems has been influenced by two processes: deadly tsunamis and available technology. In this paper, we explore the evolution of science and technology used in tsunami warning systems, the evolution of their products using warning technologies, and offer suggestions for a new generation of warning products, aimed at the flooding nature of the hazard, to reduce future tsunami impacts on society. We conclude that coastal communities would be well served by receiving three standardized, accurate, real-time tsunami warning products, namely (i) tsunami energy estimate, (ii) flooding maps and (iii) tsunami-induced harbour current maps to minimize the impact of tsunamis. Such information would arm communities with vital flooding guidance for evacuations and port operations. The advantage of global standardized flooding products delivered in a common format is efficiency and accuracy, which leads to effectiveness in promoting tsunami resilience at the community level. PMID:26392620

  1. Evolution of tsunami warning systems and products

    PubMed Central

    Bernard, Eddie; Titov, Vasily

    2015-01-01

    Each year, about 60 000 people and $4 billion (US$) in assets are exposed to the global tsunami hazard. Accurate and reliable tsunami warning systems have been shown to provide a significant defence for this flooding hazard. However, the evolution of warning systems has been influenced by two processes: deadly tsunamis and available technology. In this paper, we explore the evolution of science and technology used in tsunami warning systems, the evolution of their products using warning technologies, and offer suggestions for a new generation of warning products, aimed at the flooding nature of the hazard, to reduce future tsunami impacts on society. We conclude that coastal communities would be well served by receiving three standardized, accurate, real-time tsunami warning products, namely (i) tsunami energy estimate, (ii) flooding maps and (iii) tsunami-induced harbour current maps to minimize the impact of tsunamis. Such information would arm communities with vital flooding guidance for evacuations and port operations. The advantage of global standardized flooding products delivered in a common format is efficiency and accuracy, which leads to effectiveness in promoting tsunami resilience at the community level. PMID:26392620

  2. Steel and titanium hollow sphere foams

    SciTech Connect

    Hurysz, K.M.; Clark, J.L.; Nagel, A.R.; Lee, K.J.; Cochran, J.K.; Sanders, T.H. Jr.; Hardwicke, C.U.

    1998-12-31

    Metal hollow sphere foams are fabricated by bonding millimeter sized metal alloy hollow spheres at points of contact. The spheres are formed as powder shells from slurries. For stainless steel spheres, the starting powder is a mixture of iron and chromium oxide. Thermal treatment in hydrogen reduces the oxides to Fe/Cr alloys with less than 2% porosity in sphere walls. The nominal composition is close to that of 405 stainless. Carburization in CO/CO{sub 2} atmosphere followed by heat treatment produces foams of either 410 or 420 type stainless steels depending on carbon content. Compressive stress-strain behavior was measured on point contact bonded stainless foams both before and after carburization. Hardness measurements on steel sphere walls were used to estimate the yield strength. Relative strengths of the foams were positioned between open and closed cell models. This was encouraging because bonding in the foams was less than optimum and the hollow sphere walls contained defects. As processing improves, strengths should increase. To produce titanium alloy spheres, the starting powder is titanium alloy hydride. Thermal treatment in an inert atmosphere decomposes the hydride and sinters the titanium powder in the sphere walls to greater than 96% relative density. Both titanium and Ti-6V-4V spheres and foams have been produced. Oxygen contents are a concern for titanium compositions and processing is being altered to reduce oxygen levels to increase ductility.

  3. 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.

  4. Perturbative Casimir Energies of Spheres

    NASA Astrophysics Data System (ADS)

    Barton, G.

    The Casimir energies of single bodies (as opposed to the interaction between mutually disjoint bodies) have accumulated deceptive folklore which this talk will try to exorcise, by mean of calculations for atomic solids that, though optically dilute, are realistically dispersive. This is easy, because quantum electrodynamics then yields identically the same energy as one gets from the properly retarded interatomic potentials. The problem of regularizing (nominal) divergences turns out to be quite distinct from the appropriate process of renormalization: simply discarding all nominally divergent contributions would prevent one from understanding the physics. Contrary to legend, the pertinent Casimir energies for dielectric spheres are attractive.

  5. The dynamic sphere test problem

    SciTech Connect

    Chabaud, Brandon M.; Brock, Jerry S.; Smith, Brandon M.

    2012-05-16

    In this manuscript we define the dynamic sphere problem as a spherical shell composed of a homogeneous, linearly elastic material. The material exhibits either isotropic or transverse isotropic symmetry. When the problem is formulated in material coordinates, the balance of mass equation is satisfied automatically. Also, the material is assumed to be kept at constant temperature, so the only relevant equation is the equation of motion. The shell has inner radius r{sub i} and outer radius r{sub o}. Initially, the shell is at rest. We assume that the interior of the shell is a void and we apply a time-varying radial stress on the outer surface.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. SPHERES: Design of a Formation Flying Testbed for ISS

    NASA Astrophysics Data System (ADS)

    Sell, S. W.; Chen, S. E.

    2002-01-01

    operations, satellites will autonomously perform various maneuvers with one to three satellites operating simultaneously, involving a crew member only to upload protocols and replace satellite consumables (gas and power) during the test session. Once completed, data will be downlinked to the ground for analysis by the SPHERES team, facilitating the iterative process of new and/or modified protocols being uplinked for use in the next test session. SPHERES has prior flight experience on the NASA KC-135 Reduced Gravity aircraft and has also been in constant use in laboratory air table testing for almost two years. Slated for launch to the International Space Station on ISS12A.1, SPHERES will use its six-month flight to conduct risk-reduction investigations involving the coordinated motion of multiple satellites in a micro-gravity environment.

  14. Sphere Drag and Heat Transfer.

    PubMed

    Duan, Zhipeng; He, Boshu; Duan, Yuanyuan

    2015-07-20

    Modelling fluid flows past a body is a general problem in science and engineering. Historical sphere drag and heat transfer data are critically examined. The appropriate drag coefficient is proposed to replace the inertia type definition proposed by Newton. It is found that the appropriate drag coefficient is a desirable dimensionless parameter to describe fluid flow physical behavior so that fluid flow problems can be solved in the simple and intuitive manner. The appropriate drag coefficient is presented graphically, and appears more general and reasonable to reflect the fluid flow physical behavior than the traditional century old drag coefficient diagram. Here we present drag and heat transfer experimental results which indicate that there exists a relationship in nature between the sphere drag and heat transfer. The role played by the heat flux has similar nature as the drag. The appropriate drag coefficient can be related to the Nusselt number. This finding opens new possibilities in predicting heat transfer characteristics by drag data. As heat transfer for flow over a body is inherently complex, the proposed simple means may provide an insight into the mechanism of heat transfer for flow past a body.

  15. Sphere Drag and Heat Transfer

    NASA Astrophysics Data System (ADS)

    Duan, Zhipeng; He, Boshu; Duan, Yuanyuan

    2015-07-01

    Modelling fluid flows past a body is a general problem in science and engineering. Historical sphere drag and heat transfer data are critically examined. The appropriate drag coefficient is proposed to replace the inertia type definition proposed by Newton. It is found that the appropriate drag coefficient is a desirable dimensionless parameter to describe fluid flow physical behavior so that fluid flow problems can be solved in the simple and intuitive manner. The appropriate drag coefficient is presented graphically, and appears more general and reasonable to reflect the fluid flow physical behavior than the traditional century old drag coefficient diagram. Here we present drag and heat transfer experimental results which indicate that there exists a relationship in nature between the sphere drag and heat transfer. The role played by the heat flux has similar nature as the drag. The appropriate drag coefficient can be related to the Nusselt number. This finding opens new possibilities in predicting heat transfer characteristics by drag data. As heat transfer for flow over a body is inherently complex, the proposed simple means may provide an insight into the mechanism of heat transfer for flow past a body.

  16. Sphere Drag and Heat Transfer

    PubMed Central

    Duan, Zhipeng; He, Boshu; Duan, Yuanyuan

    2015-01-01

    Modelling fluid flows past a body is a general problem in science and engineering. Historical sphere drag and heat transfer data are critically examined. The appropriate drag coefficient is proposed to replace the inertia type definition proposed by Newton. It is found that the appropriate drag coefficient is a desirable dimensionless parameter to describe fluid flow physical behavior so that fluid flow problems can be solved in the simple and intuitive manner. The appropriate drag coefficient is presented graphically, and appears more general and reasonable to reflect the fluid flow physical behavior than the traditional century old drag coefficient diagram. Here we present drag and heat transfer experimental results which indicate that there exists a relationship in nature between the sphere drag and heat transfer. The role played by the heat flux has similar nature as the drag. The appropriate drag coefficient can be related to the Nusselt number. This finding opens new possibilities in predicting heat transfer characteristics by drag data. As heat transfer for flow over a body is inherently complex, the proposed simple means may provide an insight into the mechanism of heat transfer for flow past a body. PMID:26189698

  17. Porous Ceramic Spheres from Ion Exchange Resin

    NASA Technical Reports Server (NTRS)

    Dynys, Fred

    2005-01-01

    A commercial cation ion exchange resin, cross-linked polystyrene, has been successfully used as a template to fabricate 20 to 50 micron porous ceramic spheres. Ion exchange resins have dual template capabilities. Pore architecture of the ceramic spheres can be altered by changing the template pattern. Templating can be achieved by utilizing the internal porous structure or the external surface of the resin beads. Synthesis methods and chemical/physical characteristics of the ceramic spheres will be reported.

  18. Process for making hollow carbon spheres

    DOEpatents

    Luhrs, Claudia C.; Phillips, Jonathan; Richard, Monique N.; Knapp, Angela Michelle

    2013-04-16

    A hollow carbon sphere having a carbon shell and an inner core is disclosed. The hollow carbon sphere has a total volume that is equal to a volume of the carbon shell plus an inner free volume within the carbon shell. The inner free volume is at least 25% of the total volume. In some instances, a nominal diameter of the hollow carbon sphere is between 10 and 180 nanometers.

  19. Impingement of Water Droplets on a Sphere

    NASA Technical Reports Server (NTRS)

    Dorsch, Robert G.; Saper, Paul G.; Kadow, Charles F.

    1955-01-01

    Droplet trajectories about a sphere in ideal fluid flow were calculated. From the calculated droplet trajectories the droplet impingement characteristics of the sphere were determined. Impingement data and equations for determining the collection efficiency, the area, and the distribution of impingement are presented in terms of dimensionless parameters. The range of flight and atmospheric conditions covered in the calculations was extended considerably beyond the range covered by previously reported calculations for the sphere.

  20. Instructors' Use of Trigger Warnings and Behavior Warnings in Abnormal Psychology

    ERIC Educational Resources Information Center

    Boysen, Guy A.; Wells, Anna Mae; Dawson, Kaylee J.

    2016-01-01

    College students have been increasingly demanding warnings and accommodations in relation to course topics they believe will elicit strong, negative emotions. These "trigger warnings" are highly relevant to Abnormal Psychology because of the sensitive topics covered in the course (e.g., suicide, trauma, sex). A survey of Abnormal…

  1. An airborne FLIR detection and warning system for low altitude wind shear

    NASA Technical Reports Server (NTRS)

    Sinclair, Peter C.; Kuhn, Peter M.

    1991-01-01

    It is shown through some preliminary flight measurement research that a forward looking infrared radiometer (FLIR) system can be used to successfully detect the cool downdraft of downbursts (microbusts/macrobursts) and thunderstorm gust front outflows that are responsible for most of the low altitude wind shear (LAWS) events. The FLIR system provides a much greater safety margin for the pilot than that provided by reactive designs such as inertial air speed systems. Preliminary results indicate that an advanced airborne FLIR system could provide the pilot with remote indication of microburst (MB) hazards along the flight path ahead of the aircraft. Results of a flight test of a prototype FLIR system show that a minimum warning time of one to four minutes (5 to 10 km), depending on aircraft speed, is available to the pilot prior to the microburst encounter.

  2. Method for producing small hollow spheres

    DOEpatents

    Hendricks, Charles D. [Livermore, CA

    1979-01-09

    Method for producing small hollow spheres of glass, metal or plastic, wherein the sphere material is mixed with or contains as part of the composition a blowing agent which decomposes at high temperature (T .gtorsim. 600.degree. C). As the temperature is quickly raised, the blowing agent decomposes and the resulting gas expands from within, thus forming a hollow sphere of controllable thickness. The thus produced hollow spheres (20 to 10.sup.3 .mu.m) have a variety of application, and are particularly useful in the fabrication of targets for laser implosion such as neutron sources, laser fusion physics studies, and laser initiated fusion power plants.

  3. Method for producing small hollow spheres

    DOEpatents

    Hendricks, C.D.

    1979-01-09

    Method is disclosed for producing small hollow spheres of glass, metal or plastic, wherein the sphere material is mixed with or contains as part of the composition a blowing agent which decomposes at high temperature (T [approx gt] 600 C). As the temperature is quickly raised, the blowing agent decomposes and the resulting gas expands from within, thus forming a hollow sphere of controllable thickness. The thus produced hollow spheres (20 to 10[sup 3] [mu]m) have a variety of application, and are particularly useful in the fabrication of targets for laser implosion such as neutron sources, laser fusion physics studies, and laser initiated fusion power plants. 1 fig.

  4. The water entry of decelerating spheres

    NASA Astrophysics Data System (ADS)

    Aristoff, Jeffrey M.; Truscott, Tadd T.; Techet, Alexandra H.; Bush, John W. M.

    2010-03-01

    We present the results of a combined experimental and theoretical investigation of the vertical impact of low-density spheres on a water surface. Particular attention is given to characterizing the sphere dynamics and the influence of its deceleration on the shape of the resulting air cavity. A theoretical model is developed which yields simple expressions for the pinch-off time and depth, as well as the volume of air entrained by the sphere. Theoretical predictions compare favorably with our experimental observations, and allow us to rationalize the form of water-entry cavities resulting from the impact of buoyant and nearly buoyant spheres.

  5. Science off the Sphere: Earth in Infrared

    NASA Video Gallery

    International Space Station Expedition 30 astronaut Don Pettit views cities, agricultural areas and deserts using an infrared camera for 'Science off the Sphere.' Through a partnership between NASA...

  6. Environment Agency England flood warning systems

    NASA Astrophysics Data System (ADS)

    Strong, Chris; Walters, Mark; Haynes, Elizabeth; Dobson, Peter

    2015-04-01

    Context In England around 5 million homes are at risk of flooding. We invest significantly in flood prevention and management schemes but we can never prevent all flooding. Early alerting systems are fundamental to helping us reduce the impacts of flooding. The Environment Agency has had the responsibility for flood warning since 1996. In 2006 we invested in a new dissemination system that would send direct messages to pre-identified recipients via a range of channels. Since then we have continuously improved the system and service we offer. In 2010 we introduced an 'opt-out' service where we pre-registered landline numbers in flood risk areas, significantly increasing the customer base. The service has performed exceptionally well under intense flood conditions. Over a period of 3 days in December 2013, when England was experiencing an east coast storm surge, the system sent nearly 350,000 telephone messages, 85,000 emails and 70,000 text messages, with a peak call rate of around 37,000 per hour and 100% availability. The Floodline Warnings Direct (FWD) System FWD provides warnings in advance of flooding so that people at risk and responders can take action to minimise the impact of the flood. Warnings are sent via telephone, fax, text message, pager or e-mail to over 1.1 million properties located within flood risk areas in England. Triggers for issuing alerts and warnings include attained and forecast river levels and rainfall in some rapidly responding locations. There are three levels of warning: Flood Alert, Flood Warning and Severe Flood Warning, and a stand down message. The warnings can be updated to include relevant information to help inform those at risk. Working with our current provider Fujitsu, the system is under a programme of continuous improvement including expanding the 'opt-out' service to mobile phone numbers registered to at risk addresses, allowing mobile registration to the system for people 'on the move' and providing access to

  7. Predicting visibility of aircraft.

    PubMed

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

    2009-05-20

    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.

  8. 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

  9. Development of the Advance Warning Airborne System(AWAS)

    NASA Technical Reports Server (NTRS)

    Adamson, H. Patrick

    1992-01-01

    The thermal characteristics of microbursts are utilized by the AWAS IR and OAT features to provide predictive warning of hazardous microbursts ahead of the aircraft during landing or take off. The AWAS was evaluated satisfactorily in 1990 on a Cessna Citation that was intentionally flown into a number of wind shear events. The events were detected, and both the IR and OAT thermal features were shown to be effective. In 1991, AWAS units were flown on three American Airline MD-80's and three Northwest Airlines DC-9's to study and to decrease the nuisance alert response of the system. The AWAS was also flown on the NASA B737 during the summer of 1991. The results of these flights were inconclusive and disappointing. The results were not as promising as before because NASA conducted research flights which were outside of the normal operating envelope for which the AWAS is designed to operate. In an attempt to compensate for these differences in airspeed and mounting location, the automatic features of the system were sometimes overridden by NASA personnel during the flight. Each of these critical factors is discussed in detail. The effect of rain on the OAT signals is presented as a function of the air speed. Use of a 4 pole 1/20 Hertz filter is demonstrated by both the IR and thermal data. Participation in the NASA 1992 program was discussed. FAA direction in the continuing Certification program requires the addition of a reactive feature to the AWAS predictive system. This combined system will not require flight guidance on newer aircraft. The features of AWAS-IV, with the NASA algorithm included, were presented. Expected completion of the FAA Certification plan was also described.

  10. Leonid Dust Spheres Captured During the 2002 Storm?

    NASA Technical Reports Server (NTRS)

    Rietmeijer, Frans J. M.; Pfeffer, Melissa A.; Chizmadia, Lysa; Macy, B.; Fischer, T. P.; Zolensky, M. E.; Warren, J. L.; Jenniskens, P.

    2003-01-01

    An effort was made to collect dust from a known source, comet 55P/Tempel-Tuttle, in the form of Leonid meteor debris in the hours after the 2002 storm. No interplanetary dust particles (IDPs) have yet been recovered from a known source. We do not expect Leonid debris at 72 km/s to survive atmospheric entry as aggregates and our effort was predicated on the notion that mm-sized and larger meteoroids after extreme mass could survive as up to approximately 100 micron-sized silicate spheres. Two anticipated Leonid storms, rather than its annual shower activity, were the target of the last Leonid Multi-Aircraft Campaign during the Nov. 19, 2002 storm. Flying westwards from Spain to the US the mission covered both the 1767 and 1866 dust trails whereby early in the flight the aircraft flew several hours across the region exposed to the first storm peak that did not include the continental US of the second peak with 5,400 meteors.

  11. Tandem spheres in hypersonic flow

    SciTech Connect

    Laurence, Stuart J; Deiterding, Ralf; Hornung, Hans G

    2009-01-01

    The problem of determining the forces acting on a secondary body when it is travelling at some point within the shocked region created by a hypersonic primary body is of interest in such situations as store or stage separation, re-entry of multiple vehicles, and atmospheric meteoroid fragmentation. The current work is concerned with a special case of this problem, namely that in which both bodies are spheres and are stationary with respect to one another. We first present an approximate analytical model of the problem; subsequently, numerical simulations are described and results are compared with those from the analytical model. Finally, results are presented from a series of experiments in the T5 hypervelocity shock tunnel in which a newly-developed force-measurement technique was employed.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Lightning hazards to aircraft

    NASA Technical Reports Server (NTRS)

    Corn, P. B.

    1978-01-01

    Lightning hazards and, more generally, aircraft static electricity are discussed by a representative for the Air Force Flight Dynamics Laboratory. An overview of these atmospheric electricity hazards to aircraft and their systems is presented with emphasis on electrical and electronic subsystems. The discussion includes reviewing some of the characteristics of lightning and static electrification, trends in weather and lightning-related mishaps, some specific threat mechanisms and susceptible aircraft subsystems and some of the present technology gaps. A roadmap (flow chart) is presented to show the direction needed to address these problems.

  17. 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.

  18. Soft-sphere soft glasses

    NASA Astrophysics Data System (ADS)

    Heyes, D. M.; Clarke, S. M.; Brańka, A. C.

    2009-11-01

    Molecular dynamics simulations have been used to compute physical properties of model fluids in which the particles interacted via the soft-sphere pair potential (SSP) ϕ(r )=ɛ(σ /r)n, where ɛ and σ are the characteristic energy and distance, respectively. The emphasis is on small values of n, tending to the lower theromodynamically allowed bound of 3+. An accurate equation of state for the SSP fluid is obtained, consisting of two terms, and as n→3+, the compressibility factor, Z tends to Z =B2ζn /3 for ζ >0, where B2 is the second virial coefficient, and ζ =πNσ3/6V is a nominal packing fraction for N particles in volume V. A simple formula for the position of the first peak in the radial distribution function in the soft particle limit is proposed and shown to agree with the simulation data. The fluid phase velocity autocorrelation function at fluid-solid coexistence becomes more oscillatory as n decreases. Values for the self-diffusion coefficient D and shear viscosity η were calculated as a function of n and density, and these were used to estimate the n-dependence of an ideal glass transition. The glass transition shifts relatively further into the solid part of the phase diagram as softness (˜1/n) increases. D decreases by ca. 75% and η increases by about a factor of 3 along the fluid-solid coexistence line from n =∞ to 3.25. Non-Gaussian behavior was calculated from the particle displacements as a function of particle softness. A screened soft-sphere potential, SSSP, was introduced to explore the effects for small n of the long range part of the potential in relation to the scale of the local structure. The SSSP with suitable analytic form and parameters can give statistically indistinguishable results from the full SSP for the static properties, D and η.

  19. Impact damage in aircraft composite sandwich panels

    NASA Astrophysics Data System (ADS)

    Mordasky, Matthew D.

    An experimental study was conducted to develop an improved understanding of the damage caused by runway debris and environmental threats on aircraft structures. The velocities of impacts for stationary aircraft and aircraft under landing and takeoff speeds was investigated. The impact damage by concrete, asphalt, aluminum, hail and rubber sphere projectiles was explored in detail. Additionally, a kinetic energy and momentum experimental study was performed to look at the nature of the impacts in more detail. A method for recording the contact force history of the impact by an instrumented projectile was developed and tested. The sandwich composite investigated was an IM7-8552 unidirectional prepreg adhered to a NOMEXRTM core with an FM300K film adhesive. Impact experiments were conducted with a gas gun built in-house specifically for delivering projectiles to a sandwich composite target in this specic velocity regime (10--140 m/s). The effect on the impact damage by the projectile was investigated by ultrasonic C-scan, high speed camera and scanning electron and optical microscopy. Ultrasonic C-scans revealed the full extent of damage caused by each projectile, while the high speed camera enabled precise projectile velocity measurements that were used for striking velocity, kinetic energy and momentum analyses. Scanning electron and optical images revealed specific features of the panel failure and manufacturing artifacts within the lamina and honeycomb core. The damage of the panels by different projectiles was found to have a similar damage area for equivalent energy levels, except for rubber which had a damage area that increased greatly with striking velocity. Further investigation was taken by kinetic energy and momentum based comparisons of 19 mm diameter stainless steel sphere projectiles in order to examine the dominating damage mechanisms. The sandwich targets were struck by acrylic, aluminum, alumina, stainless steel and tungsten carbide spheres of the

  20. Antecedents and analogues - Experimental aircraft

    NASA Technical Reports Server (NTRS)

    Smith, R. H.

    1978-01-01

    The paper reviews the development of experimental aircraft from 1953 to the present. Consideration is given to the X-series experimental aircraft, to X-15 (the first aerospace plane), to the transition of experimental aircraft to high-speed flight, to XB-70 research, to lifting body research aircraft, and to current high-speed flight research.

  1. A survey of early warning technologies

    SciTech Connect

    Smith, G.D.; Arlowe, H.D.; Williams, J.D.

    1995-07-01

    This paper presents a survey of technologies useful in providing early warning in physical security systems. Early warning is important in virtually all types of security systems whether they are used for temporary (tactical, portable, or semi-permanent) applications, border warning, fixed-site detection, or standoff surveillance detection. With the exception of the standoff surveillance detection systems, all systems discussed in this paper usually involve a moving target. The fact that a person(s) to be detected in a standoff surveillance scenario is not moving presents challenging problems and requires different applications of technology. The technologies commonly used to detect moving targets and some suggestions for detection of stationary targets are addressed in this paper.

  2. A SDMS Model: Early Warning Coordination Centres

    NASA Astrophysics Data System (ADS)

    Santos-Reyes, Jaime

    2010-05-01

    Following the tsunami disaster in 2004, the General Secretary of the United Nations (UN) Kofi Annan called for a global early warning system for all hazards and for all communities. He also requested the ISDR (International Strategy fort Disaster Reduction) and its UN partners to conduct a global survey of capacities, gaps and opportunities in relation to early warning systems. The produced report, "Global survey of Early Warning Systems", concluded that there are many gaps and shortcomings and that much progress has been made on early warning systems and great capabilities are available around the world. However, it may be argued that an early warning system (EWS) may not be enough to prevent fatalities due to a natural hazard; i.e., it should be seen as part of a ‘wider' or total system. Furthermore, an EWS may work very well when assessed individually but it is not clear whether it will contribute to accomplish the purpose of the ‘total disaster management system'; i.e., to prevent fatalities. For instance, a regional EWS may only work if it is well co-ordinated with the local warning and emergency response systems that ensure that the warning is received, communicated and acted upon by the potentially affected communities. It may be argued that without these local measures being in place, a regional EWS will have little impact in saving lives. Researchers argued that unless people are warned in remote areas, the technology is useless; for instance McGuire [5] argues that: "I have no doubt that the technical element of the warning system will work very well,"…"But there has to be an effective and efficient communications cascade from the warning centre to the fisherman on the beach and his family and the bar owners." Similarly, McFadden [6] states that: "There's no point in spending all the money on a fancy monitoring and a fancy analysis system unless we can make sure the infrastructure for the broadcast system is there,"… "That's going to require a lot

  3. Conceptual issues in the study of dynamic hazard warnings.

    PubMed

    Meyer, Joachim

    2004-01-01

    This paper presents a conceptual analysis of dynamic hazard warning systems. The normative aspects of responses to warnings are analyzed, and a distinction is made between two forms of responses to a warning system, referred to as compliance and reliance. Determinants of the responses to warnings are identified, and they are broadly classified into normative, task, and operator factors. Existing research on warnings and automation is assessed in view of this conceptual framework, and directions for future research are discussed. Some implications of this analysis for practitioners, designers, and researchers are indicated. Actual or potential applications of this research include recommendations for the analysis, design, and study of dynamic warning systems.

  4. GIS-aided avalanche warning in Norway

    NASA Astrophysics Data System (ADS)

    Jaedicke, Christian; Syre, Egil; Sverdrup-Thygeson, Kjetil

    2014-05-01

    Avalanche warning for large areas requires the processing of an extensive amount of data. Information relating to the three basic requirements for avalanche warning - knowledge of terrain, the snow conditions, and the weather - needs to be available for the forecaster. The information is highly variable in time. The form and visualization of the data is often decisive for the use by the avalanche forecasters and therefore also for the quality of the produced forecasts. Avalanche warnings can be issued at different scales from national to regional and down to object specific. Often the same warning service is working at different scales and for different clients requiring a flexible and scalable approach. The workflow for producing avalanche forecasts must be extremely efficient - all the way from acquiring observation data, evaluating the situation, down to publishing the new forecast. In this study it has been an aim to include the entire workflow in a single web application. A Geographic Information Systems (GIS) solution was chosen to include all data needed by the forecaster for the avalanche danger evaluation. This interactive system of maps features background information for the entire country, such as topographic maps, slope steepness, aspect, hill shades and satellite images. In each avalanche warning area, all active avalanche paths are plotted including information on wind exposure. Each avalanche path is linked to a webpage with more details, such as fall height, release area elevation and pictures. The avalanche path webpage also includes information on the object at risk e.g. buildings, roads, or other objects. Thus, the forecaster can easily get an overview on the overall situation and focus on single avalanche paths to generate detailed avalanche warnings for the client.

  5. The Circle and Sphere as Great Equalizers.

    ERIC Educational Resources Information Center

    Schwartzman, Steven

    1991-01-01

    From the equality of the ratios of the surface areas and volumes of a sphere and its circumscribed cylinder, the exploration of theorems relating the ratios of surface areas and volumes of a sphere and other circumscribed solids in three dimensions, and analogous questions relating two-dimensional concepts of perimeter and area is recounted. (MDH)

  6. The "Magical" Sphere: Uncovering the Secret

    ERIC Educational Resources Information Center

    Petruševski, Vladimir M.; Bukleski, Miha

    2006-01-01

    A red sphere is seen at the bottom of a sealed glass tube filled with a colorless, transparent liquid. Holding the tube for a short period makes the sphere rise slowly from the bottom until it finally floats on the surface of the liquid. Instructions for preparing the demonstration are given, together with an explanation of the phenomenon. A…

  7. Mobile machine hazardous working zone warning system

    DOEpatents

    Schiffbauer, William H.; Ganoe, Carl W.

    1999-01-01

    A warning system is provided for a mobile working machine to alert an individual of a potentially dangerous condition in the event the individual strays into a hazardous working zone of the machine. The warning system includes a transmitter mounted on the machine and operable to generate a uniform magnetic field projecting beyond an outer periphery of the machine in defining a hazardous working zone around the machine during operation thereof. A receiver, carried by the individual and activated by the magnetic field, provides an alarm signal to alert the individual when he enters the hazardous working zone of the machine.

  8. Mobile machine hazardous working zone warning system

    DOEpatents

    Schiffbauer, W.H.; Ganoe, C.W.

    1999-08-17

    A warning system is provided for a mobile working machine to alert an individual of a potentially dangerous condition in the event the individual strays into a hazardous working zone of the machine. The warning system includes a transmitter mounted on the machine and operable to generate a uniform magnetic field projecting beyond an outer periphery of the machine in defining a hazardous working zone around the machine during operation. A receiver, carried by the individual and activated by the magnetic field, provides an alarm signal to alert the individual when he enters the hazardous working zone of the machine. 3 figs.

  9. An early warning system for environmental compliance

    SciTech Connect

    Quayle, T.A.

    1993-01-01

    This paper describes a process called an early warning system. This system is used for developing a method to monitor regulatory developments as they progress through the federal or state administrative process. The components of this early warning system, methods used to identify, analyze, communicate, and act on regulations, are addressed. The communication system includes a regulatory development tracking system and the methods used to relay information to applicable personnel. This paper also discusses the use of an environmental compliance manual and shows the relationship of the analysis of changing regulatory requirements to the revision process of the manual as well as methods of maintaining the manual as a ``living document``.

  10. Health warnings on tobacco products: international practices.

    PubMed

    Hammond, David; Reid, Jessica L

    2012-06-01

    Health warnings on tobacco products have emerged as a prominent area of tobacco control policy. Regulatory practice has rapidly evolved over the past decade to the point where health warnings on tobacco products continue to set international precedents for their size and comprehensiveness. The current paper provides a general review of current regulatory practices, including physical design features (such as size and location), message content (pictorial vs. text and content themes), and regulatory considerations such as rotation period and other novel practices. PMID:22689165

  11. Sensors Provide Early Warning of Biological Threats

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Early Warning Inc. of Troy, New York, licensed powerful biosensor technology from Ames Research Center. Incorporating carbon nanotubes tipped with single strands of nucleic acid from waterborne pathogens, the sensor can detect even minute amounts of targeted, disease causing bacteria, viruses, and parasites. Early Warning features the NASA biosensor in its water analyzer, which can provide advance alert of potential biological hazards in water used for agriculture, food and beverages, showers, and at beaches and lakes -- within hours instead of the days required by conventional laboratory methods.

  12. The Global Emergency Observation and Warning System

    NASA Technical Reports Server (NTRS)

    Bukley, Angelia P.; Mulqueen, John A.

    1994-01-01

    Based on an extensive characterization of natural hazards, and an evaluation of their impacts on humanity, a set of functional technical requirements for a global warning and relief system was developed. Since no technological breakthroughs are required to implement a global system capable of performing the functions required to provide sufficient information for prevention, preparedness, warning, and relief from natural disaster effects, a system is proposed which would combine the elements of remote sensing, data processing, information distribution, and communications support on a global scale for disaster mitigation.

  13. In Brief: Russian volcano warnings reinstated

    NASA Astrophysics Data System (ADS)

    Zielinski, Sarah

    2007-04-01

    The Kamchatka Volcanic Eruption Response Team (KVERT) is again issuing warnings for aviation during periods of activity by Kamchatkan volcanoes. KVERT had stopped issuing warnings on 1 March due to a loss of funding by the Federal Unitary Enterprise State Air Traffic Management Corporation of Russia (see Eos 88(12), 2007). The funding for this work has now resumed. KVERT is a collaborative project of scientists from the Russian Institute of Volcanology and Seismology, the Kamchatka Experimental and Methodical Seismological Department, and the Alaska Volcano Observatory.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Fabrication of long lasting phosphorescence glass spheres

    NASA Astrophysics Data System (ADS)

    Lv, Hao; Liu, Aimei; Tong, Jufang; Yi, Xunong; Li, Qianguang

    2008-12-01

    The long lasting phosphorescence glass spheres doped with Eu2O3 and Dy2O3 were prepared under the reducing atmosphere and characterized. XRD analysis indicated the glass spheres exhibited the typical diffraction peaks of SrAl2O4: Eu2+, Dy3+. The emission spectra of the glass spheres showed broad bands peaking at 510nm. The excitation spectra of the glass spheres showed broad bands ranging from 300 to 480nm. These are believed due to the 5d4f-->4f transitions of Eu2+ in the SrAl2O4: Eu2+, Dy3+ phosphors. The afterglow luminescence of the glass spheres excited by a 40W fluorescence lamp for 30min can be observed in the dark for about 15h with the naked eye.

  3. 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.

  4. 21 CFR 740.2 - Conspicuousness of warning statements.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS General § 740.2 Conspicuousness of warning... exemption pursuant to paragraph (b) of this section is established. (b) If the label of any cosmetic...

  5. 21 CFR 740.2 - Conspicuousness of warning statements.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS General § 740.2 Conspicuousness of warning... exemption pursuant to paragraph (b) of this section is established. (b) If the label of any cosmetic...

  6. 21 CFR 740.2 - Conspicuousness of warning statements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS General § 740.2 Conspicuousness of warning... exemption pursuant to paragraph (b) of this section is established. (b) If the label of any cosmetic...

  7. 21 CFR 740.2 - Conspicuousness of warning statements.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS General § 740.2 Conspicuousness of warning... exemption pursuant to paragraph (b) of this section is established. (b) If the label of any cosmetic...

  8. 21 CFR 740.2 - Conspicuousness of warning statements.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS General § 740.2 Conspicuousness of warning... exemption pursuant to paragraph (b) of this section is established. (b) If the label of any cosmetic...

  9. Missile Warning Operations Center (MWOC) Beale Air Force Base, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Missile Warning Operations Center (MWOC) - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Techinical Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  10. CPSC Warns of Carbon Monoxide Poisoning with Camping Equipment

    MedlinePlus

    ... Warns of Carbon Monoxide Poisoning Hazard with Camping Equipment The U.S. Consumer Product Safety Commission (CPSC) warns ... about the carbon monoxide (CO) hazard with camping equipment. CO can kill you! From 2002–2006, CPSC ...

  11. Conflict Prevention and Separation Assurance Method in the Small Aircraft Transportation System

    NASA Technical Reports Server (NTRS)

    Consiglio, Maria C.; Carreno, Victor A.; Williams, Daniel M.; Munoz, Cesar

    2005-01-01

    A multilayer approach to the prevention of conflicts due to the loss of aircraft-to-aircraft separation which relies on procedures and on-board automation was implemented as part of the SATS HVO Concept of Operations. The multilayer system gives pilots support and guidance during the execution of normal operations and advance warning for procedure deviations or off-nominal operations. This paper describes the major concept elements of this multilayer approach to separation assurance and conflict prevention and provides the rationale for its design. All the algorithms and functionality described in this paper have been implemented in an aircraft simulation in the NASA Langley Research Center s Air Traffic Operation Lab and on the NASA Cirrus SR22 research aircraft.

  12. 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

  13. Evaluating Warning Sound Urgency with Reaction Times

    ERIC Educational Resources Information Center

    Suied, Clara; Susini, Patrick; McAdams, Stephen

    2008-01-01

    It is well-established that subjective judgments of perceived urgency of alarm sounds can be affected by acoustic parameters. In this study, the authors investigated an objective measurement, the reaction time (RT), to test the effectiveness of temporal parameters of sounds in the context of warning sounds. Three experiments were performed using a…

  14. 30 CFR 57.14208 - Warning devices.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and.... Under conditions of limited visibility these loads shall have a warning light at the end of...

  15. 30 CFR 56.14208 - Warning devices.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment... conditions of limited visibility these loads shall have a warning light at the end of the projection....

  16. 30 CFR 56.14208 - Warning devices.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment... conditions of limited visibility these loads shall have a warning light at the end of the projection....

  17. 30 CFR 57.14208 - Warning devices.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and.... Under conditions of limited visibility these loads shall have a warning light at the end of...

  18. 40 CFR 763.95 - Warning labels.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Warning labels. 763.95 Section 763.95 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT ASBESTOS... to be ACM located in routine maintenance areas (such as boiler rooms) at each school building....

  19. 30 CFR 56.4101 - Warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Fire Prevention and Control Prohibitions/precautions/housekeeping § 56.4101 Warning signs. Readily visible signs prohibiting smoking...

  20. 30 CFR 56.4101 - Warning signs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Fire Prevention and Control Prohibitions/precautions/housekeeping § 56.4101 Warning signs. Readily visible signs prohibiting smoking...

  1. 30 CFR 57.4101 - Warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Prohibitions/precautions/housekeeping § 57.4101 Warning signs. Readily visible signs prohibiting smoking...

  2. 30 CFR 57.4101 - Warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Prohibitions/precautions/housekeeping § 57.4101 Warning signs. Readily visible signs prohibiting smoking...

  3. 30 CFR 56.4101 - Warning signs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Fire Prevention and Control Prohibitions/precautions/housekeeping § 56.4101 Warning signs. Readily visible signs prohibiting smoking...

  4. 30 CFR 56.4101 - Warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Fire Prevention and Control Prohibitions/precautions/housekeeping § 56.4101 Warning signs. Readily visible signs prohibiting smoking...

  5. 30 CFR 57.4101 - Warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Prohibitions/precautions/housekeeping § 57.4101 Warning signs. Readily visible signs prohibiting smoking...

  6. 30 CFR 57.4101 - Warning signs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Prohibitions/precautions/housekeeping § 57.4101 Warning signs. Readily visible signs prohibiting smoking...

  7. 30 CFR 57.4101 - Warning signs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Prohibitions/precautions/housekeeping § 57.4101 Warning signs. Readily visible signs prohibiting smoking...

  8. 30 CFR 56.4101 - Warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Fire Prevention and Control Prohibitions/precautions/housekeeping § 56.4101 Warning signs. Readily visible signs prohibiting smoking...

  9. 30 CFR 75.208 - Warning devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.208 Warning devices. Except during the installation of roof supports, the end of permanent roof support shall be posted with a readily visible...

  10. Thermoregulation constrains effective warning signal expression.

    PubMed

    Lindstedt, Carita; Lindström, Leena; Mappes, Johanna

    2009-02-01

    Evolution of conspicuous signals may be constrained if animal coloration has nonsignaling as well as signaling functions. In aposematic wood tiger moth (Parasemia plantaginis) larvae, the size of a warning signal (orange patch on black body) varies phenotypically and genetically. Although a large warning signal is favored as an antipredator defense, we hypothesized that thermoregulation may constrain the signal size in colder habitats. To test this hypothesis, we conducted a factorial rearing experiment with two selection lines for larval coloration (small and large signal) and with two temperature manipulations (high and low temperature environment). Temperature constrained the size and brightness of the warning signal. Larvae with a small signal had an advantage in the colder environment, which was demonstrated by a faster development time and growth rate in the low temperature treatment, compared to larvae with a large signal. Interestingly, the larvae with a small signal were found more often on the plant than the ones with a large signal, suggesting higher basking activity of the melanic (small signal) individuals in the low temperature. We conclude that the expression of aposematic display is not only defined by its efficacy against predators; variation in temperature may constrain evolution of a conspicuous warning signal and maintain variation in it.

  11. 30 CFR 56.14214 - Train warnings.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Train warnings. 56.14214 Section 56.14214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment Safety Practices and Operational Procedures...

  12. 30 CFR 57.14214 - Train warnings.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Train warnings. 57.14214 Section 57.14214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and Equipment Safety Practices and Operational Procedures...

  13. Tsunami Warning Services for the Caribbean Region

    NASA Astrophysics Data System (ADS)

    Whitmore, P. M.; Ferris, J. C.; Weinstein, S. A.

    2007-05-01

    Tsunami warning and watch services are currently provided to the Caribbean region through a collaborative effort between the two NOAA Tsunami Warning Centers (TWCs): the Pacific Tsunami Warning Center (PTWC) in Ewa Beach, Hawaii, and the West Coast/Alaska Tsunami Warning Center (WCATWC) in Palmer, Alaska. The WCATWC, in coordination with the Puerto Rico Seismic Network (PRSN), provides fast-response warning services to the U.S. territories of the Commonwealth of Puerto Rico and the U.S. Virgin Islands (PR/VI). The PTWC provides regional watch services to other countries throughout and surrounding the Caribbean Sea as part of the Intergovernmental Coordination Group for the Caribbean Sea and Adjacent Regions. This collaboration is analogous to the TWC's responsibilities in the Pacific basin: the WCATWC provides fast-response warning services for the U.S. west coast states, Alaska, and British Columbia in Canada, while the PTWC provides regional services for countries throughout and surrounding the Pacific Ocean (as well as a fast-response service for the U.S. State of Hawaii). Caribbean seismic data are transmitted to the TWCs through several means. The PRSN directly exports data to the WCATWC, providing the Center sufficient seismic data for the PR/VI region. Additionally, the PRSN provides the TWCs with data gathered from other Caribbean nations. Using modern communication capabilities, the seismic data can be processed at the TWCs at the same time it is processed locally. Another source of high- quality seismic data is the new USGS nine-station array that circles the region. The Global Seismic Network maintains several stations in Caribbean, Central American, and South American nations which are available in real-time to the TWCs. Unfortunately, sea level data coverage is sporadic in the region. The PR/VI has a relatively dense array of coastal tide gages, but coastal tide gage coverage is very sparse for the rest of the Caribbean basin. Three deep-ocean pressure

  14. Anomalies, conformal manifolds, and spheres

    NASA Astrophysics Data System (ADS)

    Gomis, Jaume; Hsin, Po-Shen; Komargodski, Zohar; Schwimmer, Adam; Seiberg, Nathan; Theisen, Stefan

    2016-03-01

    The two-point function of exactly marginal operators leads to a universal contribution to the trace anomaly in even dimensions. We study aspects of this trace anomaly, emphasizing its interpretation as a sigma model, whose target space {M} is the space of conformal field theories (a.k.a. the conformal manifold). When the underlying quantum field theory is supersymmetric, this sigma model has to be appropriately supersymmetrized. As examples, we consider in some detail {N}=(2,2) and {N}=(0,2) supersymmetric theories in d = 2 and {N}=2 supersymmetric theories in d = 4. This reasoning leads to new information about the conformal manifolds of these theories, for example, we show that the manifold is Kähler-Hodge and we further argue that it has vanishing Kähler class. For {N}=(2,2) theories in d = 2 and {N}=2 theories in d = 4 we also show that the relation between the sphere partition function and the Kähler potential of {M} follows immediately from the appropriate sigma models that we construct. Along the way we find several examples of potential trace anomalies that obey the Wess-Zumino consistency conditions, but can be ruled out by a more detailed analysis.

  15. Anomalies, conformal manifolds, and spheres

    DOE PAGES

    Gomis, Jaume; Hsin, Po-Shen; Komargodski, Zohar; Schwimmer, Adam; Seiberg, Nathan; Theisen, Stefan

    2016-03-04

    The two-point function of exactly marginal operators leads to a universal contribution to the trace anomaly in even dimensions. We study aspects of this trace anomaly, emphasizing its interpretation as a sigma model, whose target space $M$ is the space of conformal field theories (a.k.a. the conformal manifold). When the underlying quantum field theory is supersymmetric, this sigma model has to be appropriately supersymmetrized. As examples, we consider in some detail $N$ = (2; 2) and $N$ = (0; 2) supersymmetric theories in d = 2 and $N$ = 2 supersymmetric theories in d = 4. This reasoning leads tomore » new information about the conformal manifolds of these theories, for example, we show that the manifold is K ahler-Hodge and we further argue that it has vanishing K ahler class. For $N$ = (2; 2) theories in d = 2 and N = 2 theories in d = 4 we also show that the relation between the sphere partition function and the K ahler potential of $M$ follows immediately from the appropriate sigma models that we construct. Ultimately, along the way we find several examples of potential trace anomalies that obey the Wess-Zumino consistency conditions, but can be ruled out by a more detailed analysis.« less

  16. Ceramic Spheres From Cation Exchange Beads

    NASA Technical Reports Server (NTRS)

    Dynys, F. W.

    2003-01-01

    Porous ZrO2 and hollow TiO2 spheres were synthesized from a strong acid cation exchange resin. Spherical cation exchange beads, polystyrene based polymer, were used as a morphological-directing template. Aqueous ion exchange reaction was used to chemically bind (ZrO)(2+) ions to the polystyrene structure. The pyrolysis of the polystyrene at 600 C produces porous ZrO2 spheres with a surface area of 24 sq m/g with a mean sphere size of 42 microns. Hollow TiO2 spheres were synthesized by using the beads as a micro-reactor. A direct surface reaction - between titanium isopropoxide and the resin beads forms a hydrous TiO2 shell around the polystyrene core. The pyrolysis of the polystyrene core at 600 C produces hollow anatase spheres with a surface area of 42 sq m/g with a mean sphere size of 38 microns. The formation of ceramic spheres was studied by XRD, SEM and B.E.T. nitrogen adsorption measurements.

  17. Induced differentiation inhibits sphere formation in neuroblastoma.

    PubMed

    Craig, Brian T; Rellinger, Eric J; Alvarez, Alexandra L; Dusek, Haley L; Qiao, Jingbo; Chung, Dai H

    2016-08-19

    Neuroblastoma arises from the neural crest, the precursor cells of the sympathoadrenal axis, and differentiation status is a key prognostic factor used for clinical risk group stratification and treatment strategies. Neuroblastoma tumor-initiating cells have been successfully isolated from patient tumor samples and bone marrow using sphere culture, which is well established to promote growth of neural crest stem cells. However, accurate quantification of sphere-forming frequency of commonly used neuroblastoma cell lines has not been reported. Here, we show that MYCN-amplified neuroblastoma cell lines form spheres more frequently than non-MYCN-amplified cell lines. We also show that sphere formation is directly sensitive to cellular differentiation status. 13-cis-retinoic acid is a clinically used differentiating agent that induces a neuronal phenotype in neuroblastoma cells. Induced differentiation nearly completely blocked sphere formation. Furthermore, sphere formation was specifically FGF-responsive and did not respond to increasing doses of EGF. Taken together, these data suggest that sphere formation is an accurate method of quantifying the stemness phenotype in neuroblastoma. PMID:27297102

  18. Flow around spheres by dissipative particle dynamics

    NASA Astrophysics Data System (ADS)

    Chen, Shuo; Phan-Thien, Nhan; Khoo, Boo Cheong; Fan, Xi Jun

    2006-10-01

    The dissipative particle dynamics (DPD) method is used to study the flow behavior past a sphere. The sphere is represented by frozen DPD particles while the surrounding fluids are modeled by simple DPD particles (representing a Newtonian fluid). For the surface of the sphere, the conventional model without special treatment and the model with specular reflection boundary condition proposed by Revenga et al. [Comput. Phys. Commun. 121-122, 309 (1999)] are compared. Various computational domains, in which the sphere is held stationary at the center, are investigated to gage the effects of periodic conditions and walls for Reynolds number (Re)=0.5 and 50. Two types of flow conditions, uniform flow and shear flow are considered, respectively, to study the drag force and torque acting on the stationary sphere. It is found that the calculated drag force imposed on the sphere based on the model with specular reflection is slightly lower than the conventional model without special treatment. With the conventional model the drag force acting on the sphere is in better agreement with experimental correlation obtained by Brown and Lawler [J. Environ. Eng. 129, 222 (2003)] for the case of larger radius up to Re of about 5. The computed torque also approaches the analytical Stokes value when Re <1. For a force-free and torque-free sphere, its motion in the flow is captured by solving the translational and rotational equations of motion. The effects of different DPD parameters (a, γ, and σ) on the drag force and torque are studied. It shows that the dissipative coefficient (γ) mainly affects the drag force and torque, while random and conservative coefficient have little influence on them. Furthermore the settling of a single sphere in square tube is investigated, in which the wall effect is considered. Good agreement is found with the experiments of Miyamura et al. [Int. J. Multiphase Flow 7, 31 (1981)] and lattice-Boltzmann simulation results of Aidun et al. [J. Fluid Mech

  19. Tsunami warnings: Understanding in Hawai'i

    USGS Publications Warehouse

    Gregg, Chris E.; Houghton, B.F.; Paton, Douglas; Johnston, David M.; Swanson, D.A.; Yanagi, B.S.

    2007-01-01

    The devastating southeast Asian tsunami of December 26, 2004 has brought home the destructive consequences of coastal hazards in an absence of effective warning systems. Since the 1946 tsunami that destroyed much of Hilo, Hawai'i, a network of pole mounted sirens has been used to provide an early public alert of future tsunamis. However, studies in the 1960s showed that understanding of the meaning of siren soundings was very low and that ambiguity in understanding had contributed to fatalities in the 1960 tsunami that again destroyed much of Hilo. The Hawaiian public has since been exposed to monthly tests of the sirens for more than 25 years and descriptions of the system have been widely published in telephone books for at least 45 years. However, currently there remains some uncertainty in the level of public understanding of the sirens and their implications for behavioral response. Here, we show from recent surveys of Hawai'i residents that awareness of the siren tests and test frequency is high, but these factors do not equate with increased understanding of the meaning of the siren, which remains disturbingly low (13%). Furthermore, the length of time people have lived in Hawai'i is not correlated systematically with understanding of the meaning of the sirens. An additional issue is that warning times for tsunamis gene rated locally in Hawai'i will be of the order of minutes to tens of minutes and limit the immediate utility of the sirens. Natural warning signs of such tsunamis may provide the earliest warning to residents. Analysis of a survey subgroup from Hilo suggests that awareness of natural signs is only moderate, and a majority may expect notification via alerts provided by official sources. We conclude that a major change is needed in tsunami education, even in Hawai'i, to increase public understanding of, and effective response to, both future official alerts and natural warning signs of future tsunamis. ?? Springer 2006.

  20. 33 CFR 143.15 - Lights and warning devices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Lights and warning devices. 143... (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES DESIGN AND EQUIPMENT General § 143.15 Lights and warning devices. (a) OCS facilities must meet the lights and warning devices requirements under part 67 of...

  1. 33 CFR 143.15 - Lights and warning devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Lights and warning devices. 143... (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES DESIGN AND EQUIPMENT General § 143.15 Lights and warning devices. (a) OCS facilities must meet the lights and warning devices requirements under part 67 of...

  2. 49 CFR 234.211 - Security of warning system apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Security of warning system apparatus. 234.211... Maintenance, Inspection, and Testing Maintenance Standards § 234.211 Security of warning system apparatus. Highway-rail grade crossing warning system apparatus shall be secured against unauthorized entry....

  3. 49 CFR 234.211 - Security of warning system apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Security of warning system apparatus. 234.211... Maintenance, Inspection, and Testing Maintenance Standards § 234.211 Security of warning system apparatus. Highway-rail grade crossing warning system apparatus shall be secured against unauthorized entry....

  4. 14 CFR 121.289 - Landing gear: Aural warning device.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Landing gear: Aural warning device. 121.289... gear: Aural warning device. (a) Except for airplanes that comply with the requirements of § 25.729 of this chapter on or after January 6, 1992, each airplane must have a landing gear aural warning...

  5. 14 CFR 121.289 - Landing gear: Aural warning device.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Landing gear: Aural warning device. 121.289... gear: Aural warning device. (a) Except for airplanes that comply with the requirements of § 25.729 of this chapter on or after January 6, 1992, each airplane must have a landing gear aural warning...

  6. 14 CFR 121.289 - Landing gear: Aural warning device.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Landing gear: Aural warning device. 121.289... gear: Aural warning device. (a) Except for airplanes that comply with the requirements of § 25.729 of this chapter on or after January 6, 1992, each airplane must have a landing gear aural warning...

  7. 14 CFR 121.289 - Landing gear: Aural warning device.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Landing gear: Aural warning device. 121.289... gear: Aural warning device. (a) Except for airplanes that comply with the requirements of § 25.729 of this chapter on or after January 6, 1992, each airplane must have a landing gear aural warning...

  8. 21 CFR 740.1 - Establishment of warning statements.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS General § 740.1 Establishment of warning statements. (a) The label of a cosmetic product shall bear a warning statement whenever necessary or appropriate to prevent... for a cosmetic. Any such petition shall include an adequate factual basis to support the...

  9. 21 CFR 740.1 - Establishment of warning statements.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS General § 740.1 Establishment of warning statements. (a) The label of a cosmetic product shall bear a warning statement whenever necessary or appropriate to prevent... for a cosmetic. Any such petition shall include an adequate factual basis to support the...

  10. 21 CFR 740.1 - Establishment of warning statements.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS General § 740.1 Establishment of warning statements. (a) The label of a cosmetic product shall bear a warning statement whenever necessary or appropriate to prevent... for a cosmetic. Any such petition shall include an adequate factual basis to support the...

  11. 21 CFR 740.1 - Establishment of warning statements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS General § 740.1 Establishment of warning statements. (a) The label of a cosmetic product shall bear a warning statement whenever necessary or appropriate to prevent... for a cosmetic. Any such petition shall include an adequate factual basis to support the...

  12. 21 CFR 740.1 - Establishment of warning statements.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS General § 740.1 Establishment of warning statements. (a) The label of a cosmetic product shall bear a warning statement whenever necessary or appropriate to prevent... for a cosmetic. Any such petition shall include an adequate factual basis to support the...

  13. 49 CFR 234.225 - Activation of warning system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... seconds warning time for the normal operation of through trains before the grade crossing is occupied by... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GRADE CROSSING SAFETY, INCLUDING SIGNAL SYSTEMS, STATE ACTION PLANS....225 Activation of warning system. A highway-rail grade crossing warning system shall be maintained...

  14. 49 CFR 234.225 - Activation of warning system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... seconds warning time for the normal operation of through trains before the grade crossing is occupied by... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GRADE CROSSING SAFETY, INCLUDING SIGNAL SYSTEMS, STATE ACTION PLANS....225 Activation of warning system. A highway-rail grade crossing warning system shall be maintained...

  15. 33 CFR 143.15 - Lights and warning devices.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Lights and warning devices. 143... (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES DESIGN AND EQUIPMENT General § 143.15 Lights and warning devices. (a) OCS facilities must meet the lights and warning devices requirements under part 67 of...

  16. 33 CFR 143.15 - Lights and warning devices.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Lights and warning devices. 143... (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES DESIGN AND EQUIPMENT General § 143.15 Lights and warning devices. (a) OCS facilities must meet the lights and warning devices requirements under part 67 of...

  17. 33 CFR 143.15 - Lights and warning devices.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Lights and warning devices. 143... (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES DESIGN AND EQUIPMENT General § 143.15 Lights and warning devices. (a) OCS facilities must meet the lights and warning devices requirements under part 67 of...

  18. 49 CFR 230.85 - Audible warning device.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Cabs, Warning Signals, Sanders and Lights § 230.85 Audible warning device. (a) General provisions. Each steam locomotive shall be equipped with an audible warning device that produces a minimum...

  19. 49 CFR 230.85 - Audible warning device.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Cabs, Warning Signals, Sanders and Lights § 230.85 Audible warning device. (a) General provisions. Each steam locomotive shall be equipped with an audible warning device that produces a minimum...

  20. 49 CFR 230.85 - Audible warning device.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Cabs, Warning Signals, Sanders and Lights § 230.85 Audible warning device. (a) General provisions. Each steam locomotive shall be equipped with an audible warning device that produces a minimum...

  1. 49 CFR 230.85 - Audible warning device.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Cabs, Warning Signals, Sanders and Lights § 230.85 Audible warning device. (a) General provisions. Each steam locomotive shall be equipped with an audible warning device that produces a minimum...

  2. 49 CFR 230.85 - Audible warning device.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Cabs, Warning Signals, Sanders and Lights § 230.85 Audible warning device. (a) General provisions. Each steam locomotive shall be equipped with an audible warning device that produces a minimum...

  3. 14 CFR 91.223 - Terrain awareness and warning system.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Terrain awareness and warning system. 91..., and Certificate Requirements § 91.223 Terrain awareness and warning system. (a) Airplanes manufactured... seat, unless that airplane is equipped with an approved terrain awareness and warning system that as...

  4. 14 CFR 91.223 - Terrain awareness and warning system.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Terrain awareness and warning system. 91..., and Certificate Requirements § 91.223 Terrain awareness and warning system. (a) Airplanes manufactured... seat, unless that airplane is equipped with an approved terrain awareness and warning system that as...

  5. 14 CFR 91.223 - Terrain awareness and warning system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Terrain awareness and warning system. 91..., and Certificate Requirements § 91.223 Terrain awareness and warning system. (a) Airplanes manufactured... seat, unless that airplane is equipped with an approved terrain awareness and warning system that as...

  6. 14 CFR 91.223 - Terrain awareness and warning system.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Terrain awareness and warning system. 91..., and Certificate Requirements § 91.223 Terrain awareness and warning system. (a) Airplanes manufactured... seat, unless that airplane is equipped with an approved terrain awareness and warning system that as...

  7. 14 CFR 91.223 - Terrain awareness and warning system.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Terrain awareness and warning system. 91..., and Certificate Requirements § 91.223 Terrain awareness and warning system. (a) Airplanes manufactured... seat, unless that airplane is equipped with an approved terrain awareness and warning system that as...

  8. One-Year-Olds Warn Others about Negative Action Outcomes

    ERIC Educational Resources Information Center

    Knudsen, Birgit; Liszkowski, Ulf

    2013-01-01

    Warning others is a paradigm case of communicative helping and prospective action understanding. The current study addressed the ontogeny of warning in infants' gestural communication. We found that 12- and 18-month-olds ("n" = 84) spontaneously warned an adult by pointing out to her an aversive object hidden in her way…

  9. 30 CFR 56.20011 - Barricades and warning signs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Barricades and warning signs. 56.20011 Section... § 56.20011 Barricades and warning signs. Areas where health or safety hazards exist that are not immediately obvious to employees shall be barricaded, or warning signs shall be posted at all...

  10. 30 CFR 57.20011 - Barricades and warning signs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Barricades and warning signs. 57.20011 Section... Miscellaneous § 57.20011 Barricades and warning signs. Areas where health or safety hazards exist that are not immediately obvious to employees shall be barricaded, or warning signs shall be posted at all...

  11. 30 CFR 56.20011 - Barricades and warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Barricades and warning signs. 56.20011 Section... § 56.20011 Barricades and warning signs. Areas where health or safety hazards exist that are not immediately obvious to employees shall be barricaded, or warning signs shall be posted at all...

  12. 30 CFR 57.20011 - Barricades and warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Barricades and warning signs. 57.20011 Section... Miscellaneous § 57.20011 Barricades and warning signs. Areas where health or safety hazards exist that are not immediately obvious to employees shall be barricaded, or warning signs shall be posted at all...

  13. 46 CFR 153.955 - Warning signs during cargo transfer.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Warning signs during cargo transfer. 153.955 Section 153... Transfer Procedures § 153.955 Warning signs during cargo transfer. (a) When transferring cargo while fast to a dock or at anchor in port, the master shall ensure that the tankship displays a warning sign...

  14. 30 CFR 57.20011 - Barricades and warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Barricades and warning signs. 57.20011 Section... Miscellaneous § 57.20011 Barricades and warning signs. Areas where health or safety hazards exist that are not immediately obvious to employees shall be barricaded, or warning signs shall be posted at all...

  15. 30 CFR 57.20011 - Barricades and warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Barricades and warning signs. 57.20011 Section... Miscellaneous § 57.20011 Barricades and warning signs. Areas where health or safety hazards exist that are not immediately obvious to employees shall be barricaded, or warning signs shall be posted at all...

  16. 30 CFR 56.20011 - Barricades and warning signs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Barricades and warning signs. 56.20011 Section... § 56.20011 Barricades and warning signs. Areas where health or safety hazards exist that are not immediately obvious to employees shall be barricaded, or warning signs shall be posted at all...

  17. 30 CFR 56.20011 - Barricades and warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Barricades and warning signs. 56.20011 Section... § 56.20011 Barricades and warning signs. Areas where health or safety hazards exist that are not immediately obvious to employees shall be barricaded, or warning signs shall be posted at all...

  18. 30 CFR 57.20011 - Barricades and warning signs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Barricades and warning signs. 57.20011 Section... Miscellaneous § 57.20011 Barricades and warning signs. Areas where health or safety hazards exist that are not immediately obvious to employees shall be barricaded, or warning signs shall be posted at all...

  19. 30 CFR 56.20011 - Barricades and warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Barricades and warning signs. 56.20011 Section... § 56.20011 Barricades and warning signs. Areas where health or safety hazards exist that are not immediately obvious to employees shall be barricaded, or warning signs shall be posted at all...

  20. 46 CFR 153.955 - Warning signs during cargo transfer.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Warning signs during cargo transfer. 153.955 Section 153... Transfer Procedures § 153.955 Warning signs during cargo transfer. (a) When transferring cargo while fast to a dock or at anchor in port, the master shall ensure that the tankship displays a warning sign...

  1. 30 CFR 36.28 - Signal or warning device.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Signal or warning device. 36.28 Section 36.28... EQUIPMENT Construction and Design Requirements § 36.28 Signal or warning device. All mobile diesel-powered transportation equipment shall be provided with a bell, horn, or other suitable warning device convenient to...

  2. Superelastic carbon spheres under high pressure

    NASA Astrophysics Data System (ADS)

    Li, Meifen; Guo, Junjie; Xu, Bingshe

    2013-03-01

    We report a superelastic deformation behavior of carbon spheres by the in situ Raman spectroscopy in a high-pressure diamond anvil cell. The carbon spheres produced by arc discharging in toluene have a mean diameter of 200 nm and an onion-like multilayer graphitic structure. We find that the elastic coefficients, during both the compression and decompression processes, remain a constant up to 10 GPa, indicating a superior high-pressure structural stability. Such superelastic behavior is related to the isotropic and concentric configuration of carbon spheres and provides additional insight into improving the microscopic mechanical properties of small-scale particles.

  3. The water entry of decelerating spheres

    NASA Astrophysics Data System (ADS)

    Aristoff, Jeffrey; Truscott, Tadd; Techet, Alexandra; Bush, John

    2009-11-01

    We present the results of a combined experimental and theoretical investigation of the vertical impact of low-density spheres on a water surface. Particular attention is given to characterizing the sphere dynamics and the influence of its deceleration on the shape of the resulting air cavity. A theoretical model is developed that yields simple expressions for the pinch-off time and depth. Theoretical predictions compare favorably with our experimental observations, and allow us to rationalize the form of water-entry cavities resulting from the impact of buoyant and nearly buoyant spheres.

  4. Manipulator for rotating and examining small spheres

    DOEpatents

    Weinstein, Berthold W. [Livermore, CA; Willenborg, David L. [Livermore, CA

    1980-02-12

    A manipulator which provides fast, accurate rotational positioning of a small sphere, such as an inertial confinement fusion target, which allows inspecting of the entire surface of the sphere. The sphere is held between two flat, flexible tips which move equal amounts in opposite directions. This provides rolling of the ball about two orthogonal axes without any overall translation. The manipulator may be controlled, for example, by an x- and y-axis driven controlled by a mini-computer which can be programmed to generate any desired scan pattern.

  5. Manipulator for rotating and examining small spheres

    DOEpatents

    Weinstein, B.W.; Willenborg, D.L.

    1980-02-12

    A manipulator is disclosed which provides fast, accurate rotational positioning of a small sphere, such as an inertial confinement fusion target, which allows inspecting of the entire surface of the sphere. The sphere is held between two flat, flexible tips which move equal amounts in opposite directions. This provides rolling of the ball about two orthogonal axes without any overall translation. The manipulator may be controlled, for example, by an x- and y-axis driven controlled by a mini-computer which can be programmed to generate any desired scan pattern. 8 figs.

  6. Soot Aerosols in the Atmosphere: Contributions by Aircraft

    NASA Technical Reports Server (NTRS)

    Pueschel, R. F.; Verma, S.; Howard, S. D.; Goodman, J.; Ferry, G. V.; Allen, D. A.; Gore, Warren J. Y. (Technical Monitor)

    1995-01-01

    Interest in the distribution of black carbon (soot) aerosol (BCA) in the atmosphere is based on the following: (1) Because BCA has the highest absorption cross section of any compound know, it can absorb solar radiation to cause atmospheric warming; (2) Because BCA is a strong adsorber of gases, it can catalyze heterogeneous chemical reactions to modify the chemical composition of the atmosphere; (3) If aircraft emission is the major source of BCA, it can serve as an atmospheric tracer of aircraft exhaust. We collect BCA particles as small as 0.02 micrometers by wires mounted on both the DC-8 and ER-2 aircraft. After return to the laboratory, the wires are examined with a field emission scanning electron microscope to identify BCA particles by their characteristics morphology, Typically, BCA exists in the atmosphere as small particles of complex morphology. The particle sizes at the source are measured in tens of Angstrom units; after a short residence time in the atmosphere, individual particles coalesce to loosely packed agglomerates of typical dimensions 0.01 to 0.1 micrometer. We approximate the size of each BCA aggregate by that of a sphere of equivalent volume. This is done by computing the volume of a sphere whose diameter is the mean between averaged minimum and maximum dimensions of the BCA particle. While this procedure probably underestimates the actual surface area, it permits us to compare BCA size distributions among themselves and with other types of aerosols.

  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. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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).

  13. 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.

  14. LIVE DEMONSTRATION OF DISTANT EARLY WARNING SYSTEM

    NASA Astrophysics Data System (ADS)

    Hammitzsch, M.; Lendholt, M.; Wächter, J.

    2009-12-01

    The DEWS (Distant Early Warning System) [1] project, funded under the 6th Framework Programme of the European Union, has the objective to create a new generation of interoperable early warning systems based on an open sensor platform. This platform integrates OGC [2] SWE [3] compliant sensor systems for the rapid detection of earthquakes, for the monitoring of sea level, ocean floor events, and ground displacements. Based on the upstream information flow DEWS focuses on the improvement of downstream capacities of warning centres especially by improving information logistics for effective and targeted warning message aggregation for a multilingual environment. Multiple telecommunication channels will be used for the dissemination of warning messages. Wherever possible, existing standards have been integrated. The Command and Control User Interface (CCUI), a rich client application based on Eclipse RCP (Rich Client Platform) [4] and the open source GIS uDig [5], integrates various OGC services. Using WMS (Web Map Service) [6] and WFS (Web Feature Service) [7] spatial data are utilized to depict the situation picture and to integrate a simulation system via WPS (Web Processing Service) [8] to identify affected areas. Warning messages are compiled and transmitted in the OASIS [9] CAP (Common Alerting Protocol) [10] standard together with addressing information defined via EDXL-DE (Emergency Data Exchange Language - Distribution Element) [11]. Internal interfaces are realized with SOAP [12] web services. Based on results of GITEWS [13] - in particular the GITEWS Tsunami Service Bus [14] - the DEWS approach provides an implementation for tsunami early warning systems. The introductory part of the demonstration briefly explains the DEWS project, the CCUI in conjunction with operators’ workflow, the system architecture, details of information logistics and the virtual scenario of live demonstration. The live demonstration exhibits the CCUI on screen and the service

  15. Separate spheres and indirect benefits

    PubMed Central

    Brock, Dan W

    2003-01-01

    On any plausible account of the basis for health care resource prioritization, the benefits and costs of different alternative resource uses are relevant considerations in the prioritization process. Consequentialists hold that the maximization of benefits with available resources is the only relevant consideration. Non-consequentialists do not reject the relevance of consequences of benefits and costs, but insist that other considerations, and in particular the distribution of benefits and costs, are morally important as well. Whatever one's particular account of morally justified standards for the prioritization of different health interventions, we must be able to measure those interventions' benefits and costs. There are many theoretical and practical difficulties in that measurement, such as how to weigh extending life against improving health and quality of life as well as how different quality of life improvements should be valued, but they are not my concern here. This paper addresses two related issues in assessing benefits and costs for health resource prioritization. First, should benefits be restricted only to health benefits, or include as well other non health benefits such as economic benefits to employers from reducing the lost work time due to illness of their employees? I shall call this the Separate Spheres problem. Second, should only the direct benefits, such as extending life or reducing disability, and direct costs, such as costs of medical personnel and supplies, of health interventions be counted, or should other indirect benefits and costs be counted as well? I shall call this the Indirect Benefits problem. These two issues can have great importance for a ranking of different health interventions by either a cost/benefit or cost effectiveness analysis (CEA) standard. PMID:12773217

  16. 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.

  17. 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.

  18. 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.

  19. #4 Simulated Solar Sphere from Data - Interpolated

    NASA Video Gallery

    Rotating solar sphere made from a combination of imagery from the two STEREO spacecraft, together with simultaneous data from the Solar Dynamic Observatory.This movie is made from data taken on Jan...

  20. StenniSphere reopens after Hurricane Katrina

    NASA Technical Reports Server (NTRS)

    2006-01-01

    StenniSphere reopened Jan. 18, 2006, almost five months after Hurricane Katrina damaged the basement of the building that houses the visitor center. Thanks to the staff's careful preparations before the storm, no artifacts or exhibits were harmed.

  1. Acoustic levitation of a large solid sphere

    NASA Astrophysics Data System (ADS)

    Andrade, Marco A. B.; Bernassau, Anne L.; Adamowski, Julio C.

    2016-07-01

    We demonstrate that acoustic levitation can levitate spherical objects much larger than the acoustic wavelength in air. The acoustic levitation of an expanded polystyrene sphere of 50 mm in diameter, corresponding to 3.6 times the wavelength, is achieved by using three 25 kHz ultrasonic transducers arranged in a tripod fashion. In this configuration, a standing wave is created between the transducers and the sphere. The axial acoustic radiation force generated by each transducer on the sphere was modeled numerically as a function of the distance between the sphere and the transducer. The theoretical acoustic radiation force was verified experimentally in a setup consisting of an electronic scale and an ultrasonic transducer mounted on a motorized linear stage. The comparison between the numerical and experimental acoustic radiation forces presents a good agreement.

  2. Science off the Sphere: Thin Film Physics

    NASA Video Gallery

    International Space Station Expedition 30 astronaut Don Pettit demonstrates physics in space for 'Science off the Sphere.' Through a partnership between NASA and the American Physical Society you c...

  3. Elastic spheres can walk on water

    NASA Astrophysics Data System (ADS)

    Belden, Jesse; Hurd, Randy C.; Jandron, Michael A.; Bower, Allan F.; Truscott, Tadd T.

    2016-02-01

    Incited by public fascination and engineering application, water-skipping of rigid stones and spheres has received considerable study. While these objects can be coaxed to ricochet, elastic spheres demonstrate superior water-skipping ability, but little is known about the effect of large material compliance on water impact physics. Here we show that upon water impact, very compliant spheres naturally assume a disk-like geometry and dynamic orientation that are favourable for water-skipping. Experiments and numerical modelling reveal that the initial spherical shape evolves as elastic waves propagate through the material. We find that the skipping dynamics are governed by the wave propagation speed and by the ratio of material shear modulus to hydrodynamic pressure. With these insights, we explain why softer spheres skip more easily than stiffer ones. Our results advance understanding of fluid-elastic body interaction during water impact, which could benefit inflatable craft modelling and, more playfully, design of elastic aquatic toys.

  4. Science off the Sphere: Lenses and Vortices

    NASA Video Gallery

    International Space Station Expedition 30 astronaut Don Pettit demonstrates physics in space for 'Science off the Sphere.' Through a partnership between NASA and the American Physical Society you c...

  5. Science off the Sphere: Knitting Needles

    NASA Video Gallery

    International Space Station Expedition 30 astronaut Don Pettit uses knitting needles and water droplets to demonstrate physics in space for 'Science off the Sphere.' Through a partnership between N...

  6. Elastic spheres can walk on water

    PubMed Central

    Belden, Jesse; Hurd, Randy C.; Jandron, Michael A.; Bower, Allan F.; Truscott, Tadd T.

    2016-01-01

    Incited by public fascination and engineering application, water-skipping of rigid stones and spheres has received considerable study. While these objects can be coaxed to ricochet, elastic spheres demonstrate superior water-skipping ability, but little is known about the effect of large material compliance on water impact physics. Here we show that upon water impact, very compliant spheres naturally assume a disk-like geometry and dynamic orientation that are favourable for water-skipping. Experiments and numerical modelling reveal that the initial spherical shape evolves as elastic waves propagate through the material. We find that the skipping dynamics are governed by the wave propagation speed and by the ratio of material shear modulus to hydrodynamic pressure. With these insights, we explain why softer spheres skip more easily than stiffer ones. Our results advance understanding of fluid-elastic body interaction during water impact, which could benefit inflatable craft modelling and, more playfully, design of elastic aquatic toys. PMID:26842860

  7. Elastic spheres can walk on water.

    PubMed

    Belden, Jesse; Hurd, Randy C; Jandron, Michael A; Bower, Allan F; Truscott, Tadd T

    2016-01-01

    Incited by public fascination and engineering application, water-skipping of rigid stones and spheres has received considerable study. While these objects can be coaxed to ricochet, elastic spheres demonstrate superior water-skipping ability, but little is known about the effect of large material compliance on water impact physics. Here we show that upon water impact, very compliant spheres naturally assume a disk-like geometry and dynamic orientation that are favourable for water-skipping. Experiments and numerical modelling reveal that the initial spherical shape evolves as elastic waves propagate through the material. We find that the skipping dynamics are governed by the wave propagation speed and by the ratio of material shear modulus to hydrodynamic pressure. With these insights, we explain why softer spheres skip more easily than stiffer ones. Our results advance understanding of fluid-elastic body interaction during water impact, which could benefit inflatable craft modelling and, more playfully, design of elastic aquatic toys. PMID:26842860

  8. Catalytic, hollow, refractory spheres, conversions with them

    NASA Technical Reports Server (NTRS)

    Wang, Taylor G. (Inventor); Elleman, Daniel D. (Inventor); Lee, Mark C. (Inventor); Kendall, Jr., James M. (Inventor)

    1989-01-01

    Improved, heterogeneous, refractory catalysts are in the form of gas-impervious, hollow, thin-walled spheres (10) suitable formed of a shell (12) of refractory such as alumina having a cavity (14) containing a gas at a pressure greater than atmospheric pressure. The wall material may be itself catalytic or a catalytically active material coated onto the sphere as a layer (16), suitably platinum or iron, which may be further coated with a layer (18) of activator or promoter. The density of the spheres (30) can be uniformly controlled to a preselected value within .+-.10 percent of the density of the fluid reactant such that the spheres either remain suspended or slowly fall or rise through the liquid reactant.

  9. Global Tsunami Warning System Development Since 2004

    NASA Astrophysics Data System (ADS)

    Weinstein, S.; Becker, N. C.; Wang, D.; Fryer, G. J.; McCreery, C.; Hirshorn, B. F.

    2014-12-01

    The 9.1 Mw Great Sumatra Earthquake of Dec. 26, 2004, generated the most destructive tsunami in history killing 227,000 people along Indian Ocean coastlines and was recorded by sea-level instruments world-wide. This tragedy showed the Indian Ocean needed a tsunami warning system to prevent another tragedy on this scale. The Great Sumatra Earthquake also highlighted the need for tsunami warning systems in other ocean basins. Instruments for recording earthquakes and sea-level data useful for tsunami monitoring did not exist outside of the Pacific Ocean in 2004. Seismometers were few in number, and even fewer were high-quality long period broadband instruments. Nor was much of their data made available to the US tsunami warning centers (TWCs). In 2004 the US TWCs relied exclusively on instrumentation provided and maintained by IRIS and the USGS for areas outside of the Pacific.Since 2004, the US TWCs and their partners have made substantial improvements to seismic and sea-level monitoring networks with the addition of new and better instruments, densification of existing networks, better communications infrastructure, and improved data sharing among tsunami warning centers. In particular, the number of sea-level stations transmitting data in near real-time and the amount of seismic data available to the tsunami warning centers has more than tripled. The DART network that consisted of a half-dozen Pacific stations in 2004 now totals nearly 60 stations worldwide. Earthquake and tsunami science has progressed as well. It took nearly three weeks to obtain the first reliable estimates of the 2004 Sumatra Earthquake's magnitude. Today, thanks to improved seismic networks and modern computing power, TWCs use the W-phase seismic moment method to determine accurate earthquake magnitudes and focal mechanisms for great earthquakes within 25 minutes. TWC scientists have also leveraged these modern computers to generate tsunami forecasts in a matter of minutes.Progress towards a

  10. Pathfinder aircraft in flight

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Pathfinder research aircraft's solar cell arrays are prominently displayed as it touches down on the bed of Rogers Dry Lake at the Dryden Flight Research Center, Edwards, California, following a test flight. The solar arrays covered more than 75 percent of Pathfinder's upper wing surface, and provided electricity to power its six electric motors, flight controls, communications links and a host of scientific sensors. 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.)

  11. 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.)

  12. Pathfinder aircraft in flight

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Pathfinder solar-powered research aircraft heads for landing on the bed of Rogers Dry Lake at the Dryden Flight Research Center, Edwards, California, after a successful test flight Nov. 19, 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.)

  13. Pathfinder aircraft in flight

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Pathfinder solar-powered research aircraft is silhouetted against a clear blue sky as it soars aloft during a checkout flight from the Dryden Flight Research Center, Edwards, California, November, 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.)

  14. 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.)

  15. Liouville Quantum Gravity on the Riemann Sphere

    NASA Astrophysics Data System (ADS)

    David, François; Kupiainen, Antti; Rhodes, Rémi; Vargas, Vincent

    2016-03-01

    In this paper, we rigorously construct Liouville Quantum Field Theory on the Riemann sphere introduced in the 1981 seminal work by Polyakov. We establish some of its fundamental properties like conformal covariance under PSL{_2({C})}-action, Seiberg bounds, KPZ scaling laws, KPZ formula and the Weyl anomaly formula. We also make precise conjectures about the relationship of the theory to scaling limits of random planar maps conformally embedded onto the sphere.

  16. Hollow sphere ceramic particles for abradable coatings

    SciTech Connect

    Longo, F.N.; Bader, N.F. III; Dorfman, M.R.

    1984-05-22

    A hollow sphere ceramic flame spray powder is disclosed. The desired constituents are first formed into agglomerated particles in a spray drier. Then the agglomerated particles are introduced into a plasma flame which is adjusted so that the particles collected are substantially hollow. The hollow sphere ceramic particles are suitable for flame spraying a porous and abradable coating. The hollow particles may be selected from the group consisting of zirconium oxide and magnesium zirconate.

  17. Approximating spheroid inductive responses using spheres

    SciTech Connect

    Smith, J. Torquil; Morrison, H. Frank

    2003-12-12

    The response of high permeability ({mu}{sub r} {ge} 50) conductive spheroids of moderate aspect ratios (0.25 to 4) to excitation by uniform magnetic fields in the axial or transverse directions is approximated by the response of spheres of appropriate diameters, of the same conductivity and permeability, with magnitude rescaled based on the differing volumes, D.C. magnetizations, and high frequency limit responses of the spheres and modeled spheroids.

  18. 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.

  19. 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.

  20. 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.

  1. Solar powered aircraft

    SciTech Connect

    Phillips, W.H.

    1983-11-15

    A cruciform wing structure for a solar powered aircraft is disclosed. Solar cells are mounted on horizontal wing surfaces. Wing surfaces with spanwise axis perpendicular to surfaces maintain these surfaces normal to the sun's rays by allowing aircraft to be flown in a controlled pattern at a large bank angle. The solar airplane may be of conventional design with respect to fuselage, propeller and tail, or may be constructed around a core and driven by propeller mechanisms attached near the tips of the airfoils.

  2. Solar powered aircraft

    NASA Technical Reports Server (NTRS)

    Phillips, W. H. (Inventor)

    1983-01-01

    A cruciform wing structure for a solar powered aircraft is disclosed. Solar cells are mounted on horizontal wing surfaces. Wing surfaces with spanwise axis perpendicular to surfaces maintain these surfaces normal to the Sun's rays by allowing aircraft to be flown in a controlled pattern at a large bank angle. The solar airplane may be of conventional design with respect to fuselage, propeller and tail, or may be constructed around a core and driven by propeller mechanisms attached near the tips of the airfoils.

  3. 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.

  4. Social Interactions Sparked by Pictorial Warnings on Cigarette Packs.

    PubMed

    Hall, Marissa G; Peebles, Kathryn; Bach, Laura E; Noar, Seth M; Ribisl, Kurt M; Brewer, Noel T

    2015-10-01

    The Message Impact Framework suggests that social interactions may offer smokers the opportunity to process pictorial warnings on cigarette packs more deeply. We aimed to describe adult smokers' social interactions about pictorial cigarette pack warnings in two longitudinal pilot studies. In Pilot Study 1, 30 smokers used cigarette packs with one of nine pictorial warnings for two weeks. In Pilot Study 2, 46 smokers used cigarette packs with one of five pictorial warnings for four weeks. Nearly all smokers (97%/96% in Pilot Study 1/2) talked about the warnings with other people, with the most common people being friends (67%/87%) and spouses/significant others (34%/42%). Pilot Study 2 found that 26% of smokers talked about the warnings with strangers. Discussions about the health effects of smoking and quitting smoking were more frequent during the first week of exposure to pictorial warnings than in the week prior to beginning the study (both p < 0.05). Pictorial warnings sparked social interactions about the warnings, the health effects of smoking, and quitting smoking, indicating that pictorial warnings may act as a social intervention reaching beyond the individual. Future research should examine social interactions as a potential mediator of the impact of pictorial warnings on smoking behavior. PMID:26506363

  5. Social Interactions Sparked by Pictorial Warnings on Cigarette Packs

    PubMed Central

    Hall, Marissa G.; Peebles, Kathryn; Bach, Laura E.; Noar, Seth M.; Ribisl, Kurt M.; Brewer, Noel T.

    2015-01-01

    The Message Impact Framework suggests that social interactions may offer smokers the opportunity to process pictorial warnings on cigarette packs more deeply. We aimed to describe adult smokers’ social interactions about pictorial cigarette pack warnings in two longitudinal pilot studies. In Pilot Study 1, 30 smokers used cigarette packs with one of nine pictorial warnings for two weeks. In Pilot Study 2, 46 smokers used cigarette packs with one of five pictorial warnings for four weeks. Nearly all smokers (97%/96% in Pilot Study 1/2) talked about the warnings with other people, with the most common people being friends (67%/87%) and spouses/significant others (34%/42%). Pilot Study 2 found that 26% of smokers talked about the warnings with strangers. Discussions about the health effects of smoking and quitting smoking were more frequent during the first week of exposure to pictorial warnings than in the week prior to beginning the study (both p < 0.05). Pictorial warnings sparked social interactions about the warnings, the health effects of smoking, and quitting smoking, indicating that pictorial warnings may act as a social intervention reaching beyond the individual. Future research should examine social interactions as a potential mediator of the impact of pictorial warnings on smoking behavior. PMID:26506363

  6. Inverse Magnus effect on a rotating sphere

    NASA Astrophysics Data System (ADS)

    Kim, Jooha; Park, Hyungmin; Choi, Haecheon; Yoo, Jung Yul

    2011-11-01

    In this study, we investigate the flow characteristics of rotating spheres in the subcritical Reynolds number (Re) regime by measuring the drag and lift forces on the sphere and the two-dimensional velocity in the wake. The experiment is conducted in a wind tunnel at Re = 0 . 6 ×105 - 2 . 6 ×105 and the spin ratio (ratio of surface velocity to the free-stream velocity) of 0 (no spin) - 0.5. The drag coefficient on a stationary sphere remains nearly constant at around 0.52. However, the magnitude of lift coefficient is nearly zero at Re < 2 . 0 ×105 , but rapidly increases to 0.3 and then remains constant with further increasing Reynolds number. On the other hand, with rotation, the lift coefficient shows negative values, called inverse Magnus effect, depending on the magnitudes of the Reynolds number and spin ratio. The velocity field measured from a particle image velocimetry (PIV) indicates that non-zero lift coefficient on a stationary sphere at Re > 2 . 0 ×105 results from the asymmetry of separation line, whereas the inverse Magnus effect for the rotating sphere results from the differences in the boundary-layer growth and separation along the upper and lower sphere surfaces. Supported by the WCU, Converging Research Center and Priority Research Centers Program, NRF, MEST, Korea.

  7. Voice warning systems: Some experimental evidence concerning application

    NASA Astrophysics Data System (ADS)

    Reinecke, M.

    1981-06-01

    Two experiments with voice warning systems (VWS), one in a helicopter UH-1D and the other one in a F 104 flight simulator are described. In the first experiment recognition times to identify simulated failures were measured in cruise and low level flights with 5 pilots. It was proved that voice warnings compared to light warnings do reduce recognition time. This is especially true during low level flight, and when only precise warning texts are used. In the second experiment the interaction of voice warnings and radio communication was investigated. Eleven pilots had to do a navigation flight and to react with correct emergency procedures when failures were introduced. Reaction times suggest that additional light warnings tend to slow down pilots reactions. The findings stress the possibility that the pilot might become overloaded when voice warnings do occur while radio communication is going on.

  8. 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.

  9. Urban flood risk warning under rapid urbanization.

    PubMed

    Chen, Yangbo; Zhou, Haolan; Zhang, Hui; Du, Guoming; Zhou, Jinhui

    2015-05-01

    In the past decades, China has observed rapid urbanization, the nation's urban population reached 50% in 2000, and is still in steady increase. Rapid urbanization in China has an adverse impact on urban hydrological processes, particularly in increasing the urban flood risks and causing serious urban flooding losses. Urban flooding also increases health risks such as causing epidemic disease break out, polluting drinking water and damaging the living environment. In the highly urbanized area, non-engineering measurement is the main way for managing urban flood risk, such as flood risk warning. There is no mature method and pilot study for urban flood risk warning, the purpose of this study is to propose the urban flood risk warning method for the rapidly urbanized Chinese cities. This paper first presented an urban flood forecasting model, which produces urban flood inundation index for urban flood risk warning. The model has 5 modules. The drainage system and grid dividing module divides the whole city terrain into drainage systems according to its first-order river system, and delineates the drainage system into grids based on the spatial structure with irregular gridding technique; the precipitation assimilation module assimilates precipitation for every grids which is used as the model input, which could either be the radar based precipitation estimation or interpolated one from rain gauges; runoff production module classifies the surface into pervious and impervious surface, and employs different methods to calculate the runoff respectively; surface runoff routing module routes the surface runoff and determines the inundation index. The routing on surface grid is calculated according to the two dimensional shallow water unsteady flow algorithm, the routing on land channel and special channel is calculated according to the one dimensional unsteady flow algorithm. This paper then proposed the urban flood risk warning method that is called DPSIR model based

  10. Urban flood risk warning under rapid urbanization.

    PubMed

    Chen, Yangbo; Zhou, Haolan; Zhang, Hui; Du, Guoming; Zhou, Jinhui

    2015-05-01

    In the past decades, China has observed rapid urbanization, the nation's urban population reached 50% in 2000, and is still in steady increase. Rapid urbanization in China has an adverse impact on urban hydrological processes, particularly in increasing the urban flood risks and causing serious urban flooding losses. Urban flooding also increases health risks such as causing epidemic disease break out, polluting drinking water and damaging the living environment. In the highly urbanized area, non-engineering measurement is the main way for managing urban flood risk, such as flood risk warning. There is no mature method and pilot study for urban flood risk warning, the purpose of this study is to propose the urban flood risk warning method for the rapidly urbanized Chinese cities. This paper first presented an urban flood forecasting model, which produces urban flood inundation index for urban flood risk warning. The model has 5 modules. The drainage system and grid dividing module divides the whole city terrain into drainage systems according to its first-order river system, and delineates the drainage system into grids based on the spatial structure with irregular gridding technique; the precipitation assimilation module assimilates precipitation for every grids which is used as the model input, which could either be the radar based precipitation estimation or interpolated one from rain gauges; runoff production module classifies the surface into pervious and impervious surface, and employs different methods to calculate the runoff respectively; surface runoff routing module routes the surface runoff and determines the inundation index. The routing on surface grid is calculated according to the two dimensional shallow water unsteady flow algorithm, the routing on land channel and special channel is calculated according to the one dimensional unsteady flow algorithm. This paper then proposed the urban flood risk warning method that is called DPSIR model based

  11. Satellite Threat Warning and Attack Reporting

    SciTech Connect

    Hilland, D.; Phipps, G.; Jingle, C.; Newton, G.

    1997-12-31

    The Air Force Research Laboratory`s Satellite Threat Warning and Attack Reporting (STW/AR) program will provide technologies for advanced threat warning and reporting of radio frequency (RF) and laser threats. The STW/AR program objectives are: (a) develop cost- effective technologies to detect, identify, locate, characterize, and report attacks or interference against U.S. and Allied satellites. (b) demonstrate innovative, light-weight, low-power, laser and RF sensors. The program focuses on the demonstration of RF and laser sensors. The RF sensor effort includes the investigation of interferometric antenna arrays, multi-arm spiral and butler matrix antennas, wideband receivers, adaptive processors, and improved processing algorithms. The laser sensor effort includes the investigation of alternative detectors, broadband grating and optical designs, active pixel sensing, and improved processing algorithms.

  12. Warning communication and hydraulic risk perception

    NASA Astrophysics Data System (ADS)

    Gruntfest, E.; Caporali, E.

    2003-04-01

    In disaster management scientists must transmit their results to large groups of recipients, including decision makers and the mass media who often are not familiar with the language of science. The importance of the promotion of the hydrologic risk perception of the user communities is that many events have short lead times and high levels of uncertainty. Natural hazard mitigation processes are complex and demand several perspectives. While the rhetoric calls for extensive collaboration between disciplines, the gap between theory and practice is large, particularly in the U.S. This paper highlights results from case studies of collaborative flood warning research in Europe and in USA. Case studies on warning systems from Italy and the U.S. are included.

  13. 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.

  14. 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.

  15. Early-warning signals for critical transitions.

    PubMed

    Scheffer, Marten; Bascompte, Jordi; Brock, William A; Brovkin, Victor; Carpenter, Stephen R; Dakos, Vasilis; Held, Hermann; van Nes, Egbert H; Rietkerk, Max; Sugihara, George

    2009-09-01

    Complex dynamical systems, ranging from ecosystems to financial markets and the climate, can have tipping points at which a sudden shift to a contrasting dynamical regime may occur. Although predicting such critical points before they are reached is extremely difficult, work in different scientific fields is now suggesting the existence of generic early-warning signals that may indicate for a wide class of systems if a critical threshold is approaching.

  16. Crowd-Sourced Global Earthquake Early Warning

    NASA Astrophysics Data System (ADS)

    Minson, S. E.; Brooks, B. A.; Glennie, C. L.; Murray, J. R.; Langbein, J. O.; Owen, S. E.; Iannucci, B. A.; Hauser, D. L.

    2014-12-01

    Although earthquake early warning (EEW) has shown great promise for reducing loss of life and property, it has only been implemented in a few regions due, in part, to the prohibitive cost of building the required dense seismic and geodetic networks. However, many cars and consumer smartphones, tablets, laptops, and similar devices contain low-cost versions of the same sensors used for earthquake monitoring. If a workable EEW system could be implemented based on either crowd-sourced observations from consumer devices or very inexpensive networks of instruments built from consumer-quality sensors, EEW coverage could potentially be expanded worldwide. Controlled tests of several accelerometers and global navigation satellite system (GNSS) receivers typically found in consumer devices show that, while they are significantly noisier than scientific-grade instruments, they are still accurate enough to capture displacements from moderate and large magnitude earthquakes. The accuracy of these sensors varies greatly depending on the type of data collected. Raw coarse acquisition (C/A) code GPS data are relatively noisy. These observations have a surface displacement detection threshold approaching ~1 m and would thus only be useful in large Mw 8+ earthquakes. However, incorporating either satellite-based differential corrections or using a Kalman filter to combine the raw GNSS data with low-cost acceleration data (such as from a smartphone) decreases the noise dramatically. These approaches allow detection thresholds as low as 5 cm, potentially enabling accurate warnings for earthquakes as small as Mw 6.5. Simulated performance tests show that, with data contributed from only a very small fraction of the population, a crowd-sourced EEW system would be capable of warning San Francisco and San Jose of a Mw 7 rupture on California's Hayward fault and could have accurately issued both earthquake and tsunami warnings for the 2011 Mw 9 Tohoku-oki, Japan earthquake.

  17. Tsunamis warning from space :Ionosphere seismology

    SciTech Connect

    Larmat, Carene

    2012-09-04

    Ionosphere is the layer of the atmosphere from about 85 to 600km containing electrons and electrically charged atoms that are produced by solar radiation. Perturbations - layering affected by day and night, X-rays and high-energy protons from the solar flares, geomagnetic storms, lightning, drivers-from-below. Strategic for radio-wave transmission. This project discusses the inversion of ionosphere signals, tsunami wave amplitude and coupling parameters, which improves tsunami warning systems.

  18. Epidural steroid warning controversy still dogging FDA.

    PubMed

    Manchikanti, Laxmaiah; Candido, Kenneth D; Singh, Vijay; Gharibo, Christopher G; Boswell, Mark V; Benyamin, Ramsin M; Falco, Frank J E; Grider, Jay S; Diwan, Sudhir; Hirsch, Joshua A

    2014-01-01

    On April 23, 2014, the Food and Drug Administration (FDA) issued a letter of warning that injection of corticosteroids into the epidural space of the spine may result in rare, but serious adverse events, including "loss of vision, stroke, paralysis, and death." The advisory also advocated that patients should discuss the benefits and risks of epidural corticosteroid injections with their health care professionals, along with the benefits and risks associated with other possible treatments. In addition, the FDA stated that the effectiveness and safety of the corticosteroids for epidural use have not been established, and the FDA has not approved corticosteroids for such use. To raise awareness of the risks of epidural corticosteroid injections in the medical community, the FDA's Safe Use Initiative convened a panel of experts including pain management experts to help define the techniques for such injections with the aim of reducing preventable harm. The panel was unable to reach an agreement on 20 proposed items related to technical aspects of performing epidural injections. Subsequently, the FDA issued the above referenced warning and a notice that a panel will be convened in November 2014. This review assesses the inaccuracies of the warning and critically analyzes the available literature. The literature has been assessed in reference to alternate techniques and an understanding of the risk factors when performing transforaminal epidural injections in the cervical, thoracic, and lumbar regions, ultimately resulting in improved safety. The results of this review show the efficacy of epidural injections, with or without steroids, in a multitude of spinal ailments utilizing caudal, cervical, thoracic, and lumbar interlaminar approaches as well as lumbar transforaminal epidural injections . The evidence also shows the superiority of steroids in managing lumbar disc herniation utilizing caudal and lumbar interlaminar approaches without any significant difference as

  19. Experimental evaluation of fog warning system.

    PubMed

    Al-Ghamdi, Ali S

    2007-11-01

    Highway safety is a major concern to the public and to transportation professionals, so the number of crashes caused by poor visibility due to fog form an alarming statistic. Drivers respond to poor visibility conditions in different ways: some slow down; others do not. Many drivers simply follow the taillights of the vehicle ahead. Accordingly, hazardous conditions are created in which speeds are both too high for the prevailing conditions and highly variable. Findings are presented from a study of traffic crashes due to fog in the southern region of Saudi Arabia. The primary objective was to assess the effectiveness of fog detection and warning system on driver behavior regarding speed and headway. This warning system includes visibility sensors that automatically activate a variable message sign that posts an advisory speed when hazardous conditions due to fog occur. The system was installed on a 2 km section of a two-lane, rural highway. A data set of 36,013 observations from both experimental and control sections at two study sites was collected and analyzed. The data included vehicle speed, volume, and classification; time headway, time of day, and visibility distance. Although the warning system was ineffective in reducing speed variability, mean speed throughout the experimental sections was reduced by about 6.5 kph. This reduction indicates that the warning system appeared to have a positive effect on driver behavior in fog even though the observed mean speeds were still higher than the posted advisory speed. From relationships found in the literature between mean driving speed and number of crashes, a speed reduction of only 5 kph would yield a 15% decrease in the number of crashes.

  20. 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.

  1. The Unintended Effects of a Boxed Warning

    PubMed Central

    Eisenthal, Andrew

    2009-01-01

    Objective: To demonstrate a real-life correlation that after the US Food and Drug Administration introduced a boxed warning concerning malignancies to the labeling for topical calcineurin inhibitors, reluctance to use topical calcineurin inhibitors has led to their substitution with other therapies that have their own risks. Participants: An anonymous survey of attendees of the 2007 Fall Clinical Dermatology conference in Las Vegas, Nevada, from October 17–19, 2007. More than 95 percent of attendees were dermatologists; a small number of mid-level practitioners attended as well. Of nearly 700 attendees, the first 504 who agreed to complete the survey were included. Results: More than 40 percent of dermatologists surveyed claimed that more than 20 percent of their atopic dermatitis patients are not adequately controlled since the introduction of the boxed warning. Forty-eight percent claim that more than 20 percent of those patients were adequately controlled with topical calcineurin inhibitors as part of their regimens. Eighty percent of dermatologists surveyed agree that more than 10 precent of those patients were adequately controlled with topical calcineurin inhibitors in their regimens. Conclusion: While caution is usually prudent, the introduction of a boxed warning in the case of topical calcineurin inhibitors has led to the use of treatments that often have greater risks than the topical calcineurin inhibitors that they replaced. PMID:20729957

  2. A comparison of different informative vibrotactile forward collision warnings: does the warning need to be linked to the collision event?

    PubMed

    Gray, Rob; Ho, Cristy; Spence, Charles

    2014-01-01

    Recent research demonstrates that auditory and vibrotactile forward collision warnings presenting a motion signal (e.g., looming or apparent motion across the body surface) can facilitate speeded braking reaction times (BRTs). The purpose of the present study was to expand on this work by directly comparing warning signals in which the motion conveyed was constant across all collision events with signals in which the speed of motion was dependent on the closing velocity (CV). Two experiments were conducted using a simulated car-following task and BRTs were measured. In Experiment 1, increasing intensity (looming) vibrotactile signals were presented from a single tactor attached to the driver's waist. When the increase in intensity was CV-linked, BRTs were significantly faster as compared to a no-warning condition, however, they were not significantly different from constant intensity and CV-independent looming warnings. In Experiment 2, a vertical array of three tactors was used to create motion either towards (upwards) or away (downwards) from the driver's head. When the warning signal presented upwards motion that was CV-linked, BRTs were significantly faster than all other warning types. Downwards warnings led to a significantly higher number of brake activations in false alarm situations as compared to upwards moving warnings. The effectiveness of dynamic tactile collision warnings would therefore appear to depend on both the link between the warning and collision event and on the directionality of the warning signal.

  3. A Comparison of Different Informative Vibrotactile Forward Collision Warnings: Does the Warning Need to Be Linked to the Collision Event?

    PubMed Central

    Gray, Rob; Ho, Cristy; Spence, Charles

    2014-01-01

    Recent research demonstrates that auditory and vibrotactile forward collision warnings presenting a motion signal (e.g., looming or apparent motion across the body surface) can facilitate speeded braking reaction times (BRTs). The purpose of the present study was to expand on this work by directly comparing warning signals in which the motion conveyed was constant across all collision events with signals in which the speed of motion was dependent on the closing velocity (CV). Two experiments were conducted using a simulated car-following task and BRTs were measured. In Experiment 1, increasing intensity (looming) vibrotactile signals were presented from a single tactor attached to the driver's waist. When the increase in intensity was CV-linked, BRTs were significantly faster as compared to a no-warning condition, however, they were not significantly different from constant intensity and CV-independent looming warnings. In Experiment 2, a vertical array of three tactors was used to create motion either towards (upwards) or away (downwards) from the driver's head. When the warning signal presented upwards motion that was CV-linked, BRTs were significantly faster than all other warning types. Downwards warnings led to a significantly higher number of brake activations in false alarm situations as compared to upwards moving warnings. The effectiveness of dynamic tactile collision warnings would therefore appear to depend on both the link between the warning and collision event and on the directionality of the warning signal. PMID:24475225

  4. Warning labels formulated as questions positively influence smoking-related risk perception.

    PubMed

    Glock, Sabine; Müller, Barbara C N; Ritter, Simone M

    2013-02-01

    Research on warning labels printed on cigarette packages has shown that fear inducing health warnings might provoke defensive responses. This study investigated whether reformulating statements into questions could avoid defensive reactions. Smokers were presented with either warning labels formulated as questions, textual warning labels, graphic warning labels, or no warning labels. Participants' smoking-related risk perception was higher after exposure to warning labels formulated as questions or no warning labels than after exposure to textual or graphic warning labels. These results indicate that reformulating statements into questions can avoid defensive responses elicited by textual- and graphic warning labels. PMID:22419415

  5. 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.

  6. Aircraft to Medicine

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This video discusses how the technology of computer modeling can improve the design and durability of artificial joints for human joint replacement surgery. Also, ultrasound, originally used to detect structural flaws in aircraft, can also be used to quickly assess the severity of a burn patient's injuries, thus aiding the healing process.

  7. Aircraft mission analysis

    NASA Technical Reports Server (NTRS)

    Hauge, D. S.; Rosendaal, H. L.

    1979-01-01

    Aircraft missions, from low to hypersonic speeds, are analyzed rapidly using the FORTRAN IV program NSEG. Program employs approximate equations of motion that vary in form with type of flight segment. Takeoffs, accelerations, climbs, cruises, descents, decelerations, and landings are considered.

  8. 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.

  9. Collinear swimmer propelling a cargo sphere at low Reynolds number.

    PubMed

    Felderhof, B U

    2014-11-01

    The swimming velocity and rate of dissipation of a linear chain consisting of two or three little spheres and a big sphere is studied on the basis of low Reynolds number hydrodynamics. The big sphere is treated as a passive cargo, driven by the tail of little spheres via hydrodynamic and direct elastic interaction. The fundamental solution of Stokes equations in the presence of a sphere with a no-slip boundary condition, as derived by Oseen, is used to model the hydrodynamic interactions between the big sphere and the little spheres.

  10. Terminal energy distribution of blast waves from bursting spheres

    NASA Technical Reports Server (NTRS)

    Adamczyk, A. A.; Strehlow, R. A.

    1977-01-01

    The calculation results for the total energy delivered to the surroundings by the burst of an idealized massless sphere containing an ideal gas are presented. The logic development of various formulas for sphere energy is also presented. For all types of sphere bursts the fraction of the total initial energy available in the sphere that is delivered to the surroundings is shown to lie between that delivered for the constant pressure addition of energy to a source region and that delivered by isentropic expansion of the sphere. The relative value of E sub/Q increases at fixed sphere pressure/surrounding pressure as sphere temperature increases because the velocity of sound increases.

  11. The Separate Spheres Model of Gendered Inequality

    PubMed Central

    Miller, Andrea L.; Borgida, Eugene

    2016-01-01

    Research on role congruity theory and descriptive and prescriptive stereotypes has established that when men and women violate gender stereotypes by crossing spheres, with women pursuing career success and men contributing to domestic labor, they face backlash and economic penalties. Less is known, however, about the types of individuals who are most likely to engage in these forms of discrimination and the types of situations in which this is most likely to occur. We propose that psychological research will benefit from supplementing existing research approaches with an individual differences model of support for separate spheres for men and women. This model allows psychologists to examine individual differences in support for separate spheres as they interact with situational and contextual forces. The separate spheres ideology (SSI) has existed as a cultural idea for many years but has not been operationalized or modeled in social psychology. The Separate Spheres Model presents the SSI as a new psychological construct characterized by individual differences and a motivated system-justifying function, operationalizes the ideology with a new scale measure, and models the ideology as a predictor of some important gendered outcomes in society. As a first step toward developing the Separate Spheres Model, we develop a new measure of individuals’ endorsement of the SSI and demonstrate its reliability, convergent validity, and incremental predictive validity. We provide support for the novel hypotheses that the SSI predicts attitudes regarding workplace flexibility accommodations, income distribution within families between male and female partners, distribution of labor between work and family spheres, and discriminatory workplace behaviors. Finally, we provide experimental support for the hypothesis that the SSI is a motivated, system-justifying ideology. PMID:26800454

  12. The Separate Spheres Model of Gendered Inequality.

    PubMed

    Miller, Andrea L; Borgida, Eugene

    2016-01-01

    Research on role congruity theory and descriptive and prescriptive stereotypes has established that when men and women violate gender stereotypes by crossing spheres, with women pursuing career success and men contributing to domestic labor, they face backlash and economic penalties. Less is known, however, about the types of individuals who are most likely to engage in these forms of discrimination and the types of situations in which this is most likely to occur. We propose that psychological research will benefit from supplementing existing research approaches with an individual differences model of support for separate spheres for men and women. This model allows psychologists to examine individual differences in support for separate spheres as they interact with situational and contextual forces. The separate spheres ideology (SSI) has existed as a cultural idea for many years but has not been operationalized or modeled in social psychology. The Separate Spheres Model presents the SSI as a new psychological construct characterized by individual differences and a motivated system-justifying function, operationalizes the ideology with a new scale measure, and models the ideology as a predictor of some important gendered outcomes in society. As a first step toward developing the Separate Spheres Model, we develop a new measure of individuals' endorsement of the SSI and demonstrate its reliability, convergent validity, and incremental predictive validity. We provide support for the novel hypotheses that the SSI predicts attitudes regarding workplace flexibility accommodations, income distribution within families between male and female partners, distribution of labor between work and family spheres, and discriminatory workplace behaviors. Finally, we provide experimental support for the hypothesis that the SSI is a motivated, system-justifying ideology. PMID:26800454

  13. Tactile warning signals for in-vehicle systems.

    PubMed

    Meng, Fanxing; Spence, Charles

    2015-02-01

    The last few years have seen growing interest in the design of tactile warning signals to direct driver attention to potentially dangerous road situations (e.g. an impending crash) so that they can initiate an avoidance maneuver in a timely manner. In this review, we highlight the potential uses of such warning signals for future collision warning systems and compare them with more traditional visual and auditory warnings. Basic tactile warning signals are capable of promoting driver alertness, which has been demonstrated to be beneficial for forward collision avoidance (when compared to a no warning baseline condition). However, beyond their basic alerting function, directional tactile warning signals are now increasingly being utilized to shift the attention of the driver toward locations of interest, and thus to further facilitate their speeded responses to potential collision events. Currently, many researchers are focusing their efforts on the development of meaningful (iconic) tactile warning signals. For instance, dynamic tactile warnings (varying in their intensity and/or location) can potentially be used to convey meaningful information to drivers. Finally, we highlight the future research that will be needed in order to explore how to present multiple directional warnings using dynamic tactile cues, thus forming an integrated collision avoidance system for future in-vehicle use.

  14. 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.

  15. Braking performance of aircraft tires

    NASA Astrophysics Data System (ADS)

    Agrawal, Satish K.

    This paper brings under one cover the subject of aircraft braking performance and a variety of related phenomena that lead to aircraft hydroplaning, overruns, and loss of directional control. Complex processes involving tire deformation, tire slipping, and fluid pressures in the tire-runway contact area develop the friction forces for retarding the aircraft; this paper describes the physics of these processes. The paper reviews the past and present research efforts and concludes that the most effective way to combat the hazards associated with aircraft landings and takeoffs on contaminated runways is by measuring and displaying in realtime the braking performance parameters in the aircraft cockpit.

  16. Recent researches on the air resistance of spheres

    NASA Technical Reports Server (NTRS)

    Flachsbart, O

    1928-01-01

    The following conclusions on air resistance of spheres are drawn: 1) disturbances in front of the sphere and even single fine wires affect the critical Reynolds Number; 2) disturbances around the sphere increased the drag of the sphere without martially affecting the value of the Reynolds Number(sub crith); 3) great disturbances of the boundary layer of the sphere likewise change R.N.(sub crith); 4) turbulence of the approaching air stream lowers critical R.N.

  17. Early Warning: Development of Confidential Incident Reporting Systems

    NASA Technical Reports Server (NTRS)

    OLeary, Mike J.; Chappell, Sheryl L.; Connell, Linda (Technical Monitor)

    1996-01-01

    Accidents hardly ever happen without warning. The combination, or sequence, of failures and mistakes that cause an accident may indeed be unique but the individual failures and mistakes rarely are. In the USA in 1974 the crews on two different aircraft misunderstood the same aeronautical chart and descended towards their destination dangerously early towards a mountain. The first crew were in good weather conditions and could see the mountain and resolved their misinterpretation of the chart. The second crew six weeks later were not so lucky. In cloud they had no clues to point out their mistake nor the presence of the mountain. The resulting crash and the ensuing inquiry, which brought to light the previous incident, shocked the country but gave it the impetus to instigate a safety reporting system. This system eventually became the NASA's Aviation Safety Reporting System (ASRS). The programme collects incident reports from pilots, controllers, mechanics, cabin attendants and many others involved in aviation operations. By disseminating this safety information the ASRS has helped enormously to give US airlines and airspace the highest safety standards. Accident prevention is a goal sought by everyone in the aviation industry and establishing effective incident reporting programmes can go a long way toward achieving that goal. This article will describe the steps and issues required to establish an incident reporting system. The authors summarize the lessons learned from the ASRS, now in its twentieth year of operation and from the Confidential Human Factors Reporting (HER) Programme run by British Airways, an airline that is a recognized world leader in safety reporting and analysis. The differences between government and airline operation of confidential safety reporting systems will be addressed.

  18. Robotics Programming Competition Spheres, Russian Part

    NASA Astrophysics Data System (ADS)

    Sadovski, Andrei; Kukushkina, Natalia; Biryukova, Natalia

    2016-07-01

    Spheres" such name was done to Russian part of the Zero Robotics project which is a student competition devoted to programming of SPHERES (SPHERES - Synchronized Position Hold Engage and Reorient Experimental Satellites are the experimental robotics devices which are capable of rotation and translation in all directions, http://ssl.mit.edu/spheres/), which perform different operations on the board of International Space Station. Competition takes place online on http://zerorobotics.mit.edu. The main goal is to develop a program for SPHERES to solve an annual challenge. The end of the tournament is the real competition in microgravity on the board of ISS with a live broadcast. The Russian part of the tournament has only two years history but the problems, organization and specific are useful for the other educational projects especially for the international ones. We introduce the history of the competition, its scientific and educational goals in Russia and describe the participation of Russian teams in 2014 and 2015 tournaments. Also we discuss the organizational problems.

  19. Thermodynamic properties of non-conformal soft-sphere fluids with effective hard-sphere diameters.

    PubMed

    Rodríguez-López, Tonalli; del Río, Fernando

    2012-01-28

    In this work we study a set of soft-sphere systems characterised by a well-defined variation of their softness. These systems represent an extension of the repulsive Lennard-Jones potential widely used in statistical mechanics of fluids. This type of soft spheres is of interest because they represent quite accurately the effective intermolecular repulsion in fluid substances and also because they exhibit interesting properties. The thermodynamics of the soft-sphere fluids is obtained via an effective hard-sphere diameter approach that leads to a compact and accurate equation of state. The virial coefficients of soft spheres are shown to follow quite simple relationships that are incorporated into the equation of state. The approach followed exhibits the rescaling of the density that produces a unique equation for all systems and temperatures. The scaling is carried through to the level of the structure of the fluids. PMID:22158949

  20. Thermodynamic properties of non-conformal soft-sphere fluids with effective hard-sphere diameters.

    PubMed

    Rodríguez-López, Tonalli; del Río, Fernando

    2012-01-28

    In this work we study a set of soft-sphere systems characterised by a well-defined variation of their softness. These systems represent an extension of the repulsive Lennard-Jones potential widely used in statistical mechanics of fluids. This type of soft spheres is of interest because they represent quite accurately the effective intermolecular repulsion in fluid substances and also because they exhibit interesting properties. The thermodynamics of the soft-sphere fluids is obtained via an effective hard-sphere diameter approach that leads to a compact and accurate equation of state. The virial coefficients of soft spheres are shown to follow quite simple relationships that are incorporated into the equation of state. The approach followed exhibits the rescaling of the density that produces a unique equation for all systems and temperatures. The scaling is carried through to the level of the structure of the fluids.

  1. Absorption and scattering by bispheres, quadspheres, and circular rings of spheres and their equivalent coated spheres.

    PubMed

    Heng, Ri-Liang; Sy, Ki Cheong; Pilon, Laurent

    2015-01-01

    This study demonstrates that the absorption and scattering cross sections and asymmetry factor of randomly oriented and optically soft bispheres, quadspheres, and circular rings of spheres, with either monodisperse or polydisperse monomers, can be approximated by an equivalent coated sphere with identical volume and average projected area. This approximation could also apply to the angle-dependent scattering matrix elements for monomer size parameter less than 0.1. However, it quickly deteriorated with increasing monomer number and/or size parameter. It was shown to be superior to previously proposed approximations considering a volume equivalent homogeneous sphere and a coated sphere with identical volume and surface area. These results provide a rapid and accurate way of predicting the radiation characteristics of bispheres, quadspheres, and rings of spheres representative of various unicellular and multicellular cyanobacteria considered for producing food supplements, biofuels, and fertilizers. They could also be used in inverse methods for retrieving the monomers' optical properties, morphology, and/or concentration.

  2. Flight-deck display of neighboring aircraft wake vortices

    NASA Astrophysics Data System (ADS)

    Holforty, Wendy L.

    Over the coming decades, aviation operations are predicted to rise steadily, increasing the burden on already congested and constrained airspace. A major factor governing the safe minimum separation distance between aircraft is the hazard generated by the wake of neighboring aircraft. Unaware of their proximity to other traffic, aircraft have encountered the wake turbulence of neighboring aircraft tens of miles ahead of them with serious or fatal consequences. The wake display described herein is a perspective view, synthetic vision, flight deck display that enables flight crews to "see" neighboring aircraft, as well as their wakes via a predictive algorithm. Capable of enhancing the situational awareness with respect to the wake-vortex encounter hazard by enabling the flight crew to see the relative position of their aircraft with respect to the wake hazard, the display may allow for a decrease in the standard aircraft spacing to those now used in VFR conditions and an increase in airport and airspace capacity. At present, there is no mechanism in place in the National Airspace System that warns pilots of potential wake vortex encounters. The concept of a wake vortex display addresses the need for a real-time wake vortex avoidance scheme available directly to the pilot. The wake display has been evaluated under both simulated and actual flight conditions. Thirteen pilots with flight experience ranging from a student pilot to commercial airline and military pilots served as pilot test subjects evaluating the display under simulated conditions. The pilot test subjects completed a survey concerning their knowledge and understanding of wake vortices prior to the simulation data trials and, after the trials, they completed a pilot evaluation and postflight survey rating their experience and providing feedback for the display design. One test pilot and four guest pilots flew the display during the in-flight evaluations incorporating three wake encounter scenarios. They

  3. Physics of the granite sphere fountain

    NASA Astrophysics Data System (ADS)

    Snoeijer, Jacco H.; der Weele, Ko van

    2014-11-01

    A striking example of levitation is encountered in the "kugel fountain" where a granite sphere, sometimes weighing over a ton, is kept aloft by a thin film of flowing water. In this paper, we explain the working principle behind this levitation. We show that the fountain can be viewed as a giant ball bearing and thus forms a prime example of lubrication theory. It is demonstrated how the viscosity and flow rate of the fluid determine (i) the remarkably small thickness of the film supporting the sphere and (ii) the surprisingly long time it takes for rotations to damp out. The theoretical results compare well with measurements on a fountain holding a granite sphere of one meter in diameter. We close by discussing several related cases of levitation by lubrication.

  4. The flow past a freely rotating sphere

    NASA Astrophysics Data System (ADS)

    Fabre, David; Tchoufag, Joël; Citro, Vincenzo; Giannetti, Flavio; Luchini, Paolo

    2016-08-01

    We consider the flow past a sphere held at a fixed position in a uniform incoming flow but free to rotate around a transverse axis. A steady pitchfork bifurcation is reported to take place at a threshold Re^OS=206 leading to a state with zero torque but nonzero lift. Numerical simulations allow to characterize this state up to Re≈ 270 and confirm that it substantially differs from the steady-state solution which exists in the wake of a fixed, non-rotating sphere beyond the threshold Re^SS=212 . A weakly nonlinear analysis is carried out and is shown to successfully reproduce the results and to give substantial improvement over a previous analysis (Fabre et al. in J Fluid Mech 707:24-36, 2012). The connection between the present problem and that of a sphere in free fall following an oblique, steady (OS) path is also discussed.

  5. Unveiling the scattering behavior of small spheres

    NASA Astrophysics Data System (ADS)

    Tzarouchis, Dimitrios C.; Ylä-Oijala, Pasi; Sihvola, Ari

    2016-10-01

    A classical way for exploring the scattering behavior of a small sphere is to approximate Mie coefficients with a Taylor series expansion. This ansatz delivered a plethora of insightful results, mostly for small spheres supporting electric localized plasmonic resonances. However, many scattering aspects are still uncharted, especially with regards to magnetic resonances. Here, an alternative system ansatz is proposed based on the Padé approximants for the Mie coefficients. The results reveal the existence of a self-regulating radiative damping mechanism for the first magnetic resonance and general resonating aspects for the higher order multipoles. Hence, a systematic way of exploring the scattering response is introduced, sharpening our understanding of the sphere's scattering behavior and its emergent functionalities.

  6. WAVDRAG- ZERO-LIFT WAVE DRAG OF COMPLEX AIRCRAFT CONFIGURATIONS

    NASA Technical Reports Server (NTRS)

    Craidon, C. B.

    1994-01-01

    WAVDRAG calculates the supersonic zero-lift wave drag of complex aircraft configurations. The numerical model of an aircraft is used throughout the design process from concept to manufacturing. WAVDRAG incorporates extended geometric input capabilities to permit use of a more accurate mathematical model. With WAVDRAG, the engineer can define aircraft components as fusiform or nonfusiform in terms of non-intersecting contours in any direction or more traditional parallel contours. In addition, laterally asymmetric configurations can be simulated. The calculations in WAVDRAG are based on Whitcomb's area-rule computation of equivalent-bodies, with modifications for supersonic speed. Instead of using a single equivalent-body, WAVDRAG calculates a series of equivalent-bodies, one for each roll angle. The total aircraft configuration wave drag is the integrated average of the equivalent-body wave drags through the full roll range of 360 degrees. WAVDRAG currently accepts up to 30 user-defined components containing a maximum of 50 contours as geometric input. Each contour contains a maximum of 50 points. The Mach number, angle-of-attack, and coordinates of angle-of-attack rotation are also input. The program warns of any fusiform-body line segments having a slope larger than the Mach angle. WAVDRAG calculates total drag and the wave-drag coefficient of the specified aircraft configuration. WAVDRAG is written in FORTRAN 77 for batch execution and has been implemented on a CDC CYBER 170 series computer with a central memory requirement of approximately 63K (octal) of 60 bit words. This program was developed in 1983.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Aircraft turbofan noise

    NASA Astrophysics Data System (ADS)

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

    1987-01-01

    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 techniques 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. Areas requiring further research are discussed, and the relevance of aircraft turbofan results to quieting other turbomachinery installation is addressed.

  14. Aircraft turbofan noise

    NASA Astrophysics Data System (ADS)

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

    1983-03-01

    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.

  15. Analysis of US Food and Drug Administration Warning Letters

    PubMed Central

    Salas, Maribel; Martin, Michelle; Pisu, Maria; McCall, Erin; Zuluaga, Alvaro; Glasser, Stephen P.

    2013-01-01

    Background Recent studies have suggested that there has been an increase in the number of ‘warning letters’ issued by the US Food and Drug Administration (FDA) despite the publication of the FDA advertising guidelines. However, limited information is available on the description of warning letters. The objective of this study was to analyse the frequency and content of FDA warning letters in relation to promotional claims and discuss the influence of regulatory and industry constraints on promotion. Methods All warning letters published by the FDA between 5 May 1995 and 11 June 2007 were reviewed. Warning letters related to promotional issues were included and analysed. Information related to the identification number, date of the warning letter, FDA division that issued the letter, drug name, manufacturer, specific warning problem, type of promotional material and requested action was extracted. Two independent investigators reviewed and classified each PDF file, any differences were discussed until a consensus was reached. Results Between May 1995 and June 2007 a total of 8692 warning letters were issued, of which 25% were related to drugs. Of these, 206 warning letters focused on drug promotion and were included in this study: 23% were issued in 2005, 15% in 2004 and 14% in 1998. In total, 47% of the warning letters were issued because of false or misleading unapproved doses and uses, 27% failed to disclose risks, 15% cited misleading promotion, 8% related to misleading labelling and 3% promoted false effectiveness claims. Discussion There is an important variation in the number of warning letters issued in the last decade, probably because of the increasing number of drugs approved by the FDA, drug withdrawal scandals, and the publication of the FDA and the Pharmaceutical Research and Manufacturers of America (PhRMA) guidelines. Conclusion We found that benefit-related claims, such as unapproved uses or doses of drugs, and failure to disclose risks, are the

  16. Implicit Motivational Impact of Pictorial Health Warning on Cigarette Packs

    PubMed Central

    Volchan, Eliane; David, Isabel A.; Tavares, Gisella; Nascimento, Billy M.; Oliveira, Jose M.; Gleiser, Sonia; Szklo, Andre; Perez, Cristina; Cavalcante, Tania; Pereira, Mirtes G.; Oliveira, Leticia

    2013-01-01

    Objective The use of pictorial warning labels on cigarette packages is one of the provisions included in the first ever global health treaty by the World Health Organization against the tobacco epidemic. There is substantial evidence demonstrating the effectiveness of graphic health warning labels on intention to quit, thoughts about health risks and engaging in cessation behaviors. However, studies that address the implicit emotional drives evoked by such warnings are still underexplored. Here, we provide experimental data for the use of pictorial health warnings as a reliable strategy for tobacco control. Methods Experiment 1 pre-tested nineteen prototypes of pictorial warnings to screen for their emotional impact. Participants (n = 338) were young adults balanced in gender, smoking status and education. Experiment 2 (n = 63) tested pictorial warnings (ten) that were stamped on packs. We employed an innovative set-up to investigate the impact of the warnings on the ordinary attitude of packs’ manipulation, and quantified judgments of warnings’ emotional strength and efficacy against smoking. Findings Experiment 1 revealed that women judged the warning prototypes as more aversive than men, and smokers judged them more aversive than non-smokers. Participants with lower education judged the prototypes more aversive than participants with higher education. Experiment 2 showed that stamped warnings antagonized the appeal of the brands by imposing a cost to manipulate the cigarette packs, especially for smokers. Additionally, participants’ judgments revealed that the more aversive a warning, the more it is perceived as effective against smoking. Conclusions Health warning labels are one of the key components of the integrated approach to control the global tobacco epidemic. The evidence presented in this study adds to the understanding of how implicit responses to pictorial warnings may contribute to behavioral change. PMID:23977223

  17. Spacecraft design sensitivity for a disaster warning satellite system

    NASA Technical Reports Server (NTRS)

    Maloy, J. E.; Provencher, C. E.; Leroy, B. E.; Braley, R. C.; Shumaker, H. A.

    1977-01-01

    A disaster warning satellite (DWS) is described for warning the general public of impending natural catastrophes. The concept is responsive to NOAA requirements and maximizes the use of ATS-6 technology. Upon completion of concept development, the study was extended to establishing the sensitivity of the DWSS spacecraft power, weight, and cost to variations in both warning and conventional communications functions. The results of this sensitivity analysis are presented.

  18. 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.

  19. Mesoporous hollow spheres from soap bubbling.

    PubMed

    Yu, Xianglin; Liang, Fuxin; Liu, Jiguang; Lu, Yunfeng; Yang, Zhenzhong

    2012-02-01

    The smaller and more stable bubbles can be generated from the large parent bubbles by rupture. In the presence of a bubble blowing agent, hollow spheres can be prepared by bubbling a silica sol. Herein, the trapped gas inside the bubble acts as a template. When the porogen, i.e., other surfactant, is introduced, a mesostructured shell forms by the co-assembly with the silica sol during sol-gel process. Morphological evolution emphasizes the prerequisite of an intermediate interior gas flow rate and high exterior gas flow rate for hollow spheres. The method is valid for many compositions from inorganic, polymer to their composites. PMID:22078340

  20. Mesoporous hollow spheres from soap bubbling.

    PubMed

    Yu, Xianglin; Liang, Fuxin; Liu, Jiguang; Lu, Yunfeng; Yang, Zhenzhong

    2012-02-01

    The smaller and more stable bubbles can be generated from the large parent bubbles by rupture. In the presence of a bubble blowing agent, hollow spheres can be prepared by bubbling a silica sol. Herein, the trapped gas inside the bubble acts as a template. When the porogen, i.e., other surfactant, is introduced, a mesostructured shell forms by the co-assembly with the silica sol during sol-gel process. Morphological evolution emphasizes the prerequisite of an intermediate interior gas flow rate and high exterior gas flow rate for hollow spheres. The method is valid for many compositions from inorganic, polymer to their composites.

  1. 19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components, and... aircraft, aircraft engines, and ground flight simulators, including their parts, components, and... United States (HTSUS) by meeting the following requirements: (1) The aircraft, aircraft engines,...

  2. The duty to warn about transfusion risks.

    PubMed

    Willett, D E

    1989-03-01

    Blood banks and transfusion services should anticipate that patients contracting transfusion-transmitted diseases will claim that these facilities have a duty to warn or notify patients of potential transfusion risks. Although physicians treating patients must secure informed consent by describing significant risks and possible alternatives, precedent does not support extending informed consent requirements to the hospital or blood bank. Nonetheless, efforts to find new sources of compensation may cause judges to develop new theories of liability. Blood bank and transfusion service medical directors, therefore, are advised to provide clinicians with information regarding current or emerging transfusion risks and alternatives such as autologous transfusion, urging communication to patients when informed consent is obtained.

  3. Obstacle-warning radar for helicopters

    NASA Astrophysics Data System (ADS)

    Och, G. M.

    An obstacle warning radar concept for helicopters is described in both the test and operational phases. A radar sonde is mounted on the front of the helicopter under a radome and senses the atmosphere forward over a range of 180 deg azimuth and 32 deg elevation. The ray is directed by a fast-rotating mirror, resulting in an image-renewal rate of two per second. Obstacles can be detected to a distance of 800 m. depending on atmospheric conditions and obstacle size.

  4. Can cigarette warnings counterbalance effects of smoking scenes in movies?

    PubMed

    Golmier, Isabelle; Chebat, Jean-Charles; Gélinas-Chebat, Claire

    2007-02-01

    Scenes in movies where smoking occurs have been empirically shown to influence teenagers to smoke cigarettes. The capacity of a Canadian warning label on cigarette packages to decrease the effects of smoking scenes in popular movies has been investigated. A 2 x 3 factorial design was used to test the effects of the same movie scene with or without electronic manipulation of all elements related to smoking, and cigarette pack warnings, i.e., no warning, text-only warning, and text+picture warning. Smoking-related stereotypes and intent to smoke of teenagers were measured. It was found that, in the absence of warning, and in the presence of smoking scenes, teenagers showed positive smoking-related stereotypes. However, these effects were not observed if the teenagers were first exposed to a picture and text warning. Also, smoking-related stereotypes mediated the relationship of the combined presentation of a text and picture warning and a smoking scene on teenagers' intent to smoke. Effectiveness of Canadian warning labels to prevent or to decrease cigarette smoking among teenagers is discussed, and areas of research are proposed. PMID:17450995

  5. Influencing of warning label signal words on perceived hazard level.

    PubMed

    Wogalter, M S; Jarrard, S W; Simpson, S N

    1994-09-01

    This experiment investigated the influence of warnings, signal words, and a signal icon on perceived hazard of consumer products. Under the guise of a marketing research study, 135 people (high school students, college students, and participants from a shopping mall) rated product labels on six dimensions, including how hazardous they perceived the products to be. A total of 16 labels from actual household products were used: 9 carried the experimental conditions, and 7 were filler product labels that never carried a warning. Five conditions presented the signal words NOTE, CAUTION, WARNING, DANGER, and LETHAL together with a brief warning message. In another two conditions, a signal icon (exclamation point surrounded by a triangle) was presented together with the terms DANGER and LETHAL. In the final two conditions, one lacked a signal word but retained the warning message, and the other lacked both the warning message and the signal word. Results showed that the presence of a signal word increased perceived product hazard compared with its absence. Significant differences were noted between extreme terms (e.g., NOTE and DANGER) but not between terms usually recommended in warning design guidelines (e.g., CAUTION and WARNING). The signal icon showed no significant effect on hazard perception. Implications of the results and the value of the methodology for future warnings investigations are discussed. PMID:7989055

  6. 40 CFR 205.173-3 - Warning statement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Motorcycle Exhaust Systems § 205.173-3 Warning... for repair or replacement if the motorcycle noise has increased significantly through use....

  7. 40 CFR 205.173-3 - Warning statement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Motorcycle Exhaust Systems § 205.173-3 Warning... for repair or replacement if the motorcycle noise has increased significantly through use....

  8. 40 CFR 205.173-3 - Warning statement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Motorcycle Exhaust Systems § 205.173-3 Warning... for repair or replacement if the motorcycle noise has increased significantly through use....

  9. 40 CFR 205.173-3 - Warning statement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Motorcycle Exhaust Systems § 205.173-3 Warning... for repair or replacement if the motorcycle noise has increased significantly through use....

  10. 40 CFR 205.173-3 - Warning statement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Motorcycle Exhaust Systems § 205.173-3 Warning... for repair or replacement if the motorcycle noise has increased significantly through use....

  11. Dependence on sphere size of the phase behavior of mixtures of rods and spheres

    NASA Astrophysics Data System (ADS)

    Urakami, Naohito; Imai, Masayuki

    2003-07-01

    By the addition of chondroitin sulfate (Chs) to the aqueous suspension of tobacco mosaic virus (TMV), the aggregation of TMV occurs at very dilute TMV concentration compared with the addition of polyethylene oxide (PEO). The difference of physical behavior between Chs and PEO is the chain conformation in solution. The Chs chain has a semirigid nature, whereas the PEO chain has a flexible nature. In this study, the Chs and PEO chains are simplified to spherical particles having different size, and we use the spherocylinder model for TMV particle. The effect of the sphere size on the phase behaviors in the mixtures of rods and spheres is investigated by Monte Carlo simulations. By the addition of small spheres, the system transforms from the miscible isotropic phase to the miscible nematic phase. On the other hand, by the addition of large spheres, the system changes from the miscible isotropic phase to the immiscible nematic phase through the immiscible isotropic phase. The different phase behaviors between the small and the large spheres originate from the difference of overlapping volume of the depletion zone. In addition, we perform the Monte Carlo simulations in the case that semirigid chains are used as the Chs chain models. The same phase behaviors are observed as the mixtures of rods and large spheres. Thus the sphere model captures the phase behaviors of rod and polymer mixture systems.

  12. Voice interactive electronic warning systems (VIEWS) - An applied approach to voice technology in the helicopter cockpit

    NASA Technical Reports Server (NTRS)

    Voorhees, J. W.; Bucher, N. M.

    1983-01-01

    The cockpit has been one of the most rapidly changing areas of new aircraft design over the past thirty years. In connection with these developments, a pilot can now be considered a decision maker/system manager as well as a vehicle controller. There is, however, a trend towards an information overload in the cockpit, and information processing problems begin to occur for the rotorcraft pilot. One approach to overcome the arising difficulties is based on the utilization of voice technology to improve the information transfer rate in the cockpit with respect to both input and output. Attention is given to the background of speech technology, the application of speech technology within the cockpit, voice interactive electronic warning system (VIEWS) simulation, and methodology. Information subsystems are considered along with a dynamic simulation study, and data collection.

  13. Real-time Tsunami Warning Operations at the NOAA West Coast/Alaska Tsunami Warning Center

    NASA Astrophysics Data System (ADS)

    Whitmore, P.; Huang, P.; Crowley, H.; Ferris, J.; Hale, D.; Knight, W.; Medbery, A.; Nyland, D.; Preller, C.; Turner, B.; Urban, G.

    2007-12-01

    The West Coast/Alaska Tsunami Warning Center (WCATWC) in Palmer, Alaska and the Pacific Tsunami Warning Center (PTWC) in Ewa Beach, Hawaii, provide tsunami warning services for a large portion of the world's coasts. The WCATWC has primary responsibility for providing tsunami detection, warnings, and forecasts to Canada, Puerto Rico, Virgin Islands, and all U.S. States except Hawaii. WCATWC also acts as back-up for the PTWC, requiring the center to constantly monitor global tsunami activities by rapidly detecting and evaluating earthquakes for their tsunamigenic potential. The Centers' goals are to issue initial messages as quickly as possible to alert those near the source to potential danger (assuming there is any), and to follow that with a reasonable forecast of impact level. With these goals in mind, a Watchstander's initial action is based entirely on estimates of tsunami potential from the earthquake's source parameters. The course of action for the first message is determined primarily by the earthquake's magnitude, location, tsunami history, tsunami travel time, estimated threat based on pre-computed models, and pre-set criteria. Supplemental messages, if necessary, are based on wave observations and forecasts generated from hydrodynamic models (which are calibrated with near real-time observations). In April 2006, the WCATWC increased staff level so that the Center can be staffed 24/7 with two watchstanders. Since then, the Center's response time for events within the primary area-of-responsibility has decreased to less than 5 minutes. In order to illustrate the WCATWC's real time tsunami warning operational environment, tsunami warning operation timelines for several tsunamigenic earthquakes - including the September 12 southern Sumatra 8.4 and the January 13 Kuril Island 8.1 earthquakes - are provided. The timelines highlight the key parameters and observations that guide tsunami warning operations chronicling the event through: 1) initial alarm, 2

  14. Investigation of the misfueling of reciprocating piston aircraft engines

    NASA Technical Reports Server (NTRS)

    Scott, J. Holland, Jr.

    1988-01-01

    The Aircraft Misfueling Detection Project was developed by the Goddard Space Flight Center/Wallops Flight Facility at Wallops Island, Virginia. Its purpose was to investigate the misfueling of reciprocating piston aircraft engines by the inadvertent introduction of jet fuel in lieu of or as a contaminant of aviation gasoline. The final objective was the development of a device(s) that will satisfactorily detect misfueling and provide pilots with sufficient warning to avoid injury, fatality, or equipment damage. Two devices have been developed and successfully tested: one, a small contamination detection kit, for use by the pilot, and a second, more sensitive, modified gas chromatograph for use by the fixed-base operator. The gas chromatograph, in addition to providing excellent quality control of the fixed-base operator's fuel handling, is a very good backup for the detection kit in the event it produces negative results. Design parameters were developed to the extent that they may be applied easily to commercial production by the aircraft industry.

  15. 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.

  16. Enhanced chemical weapon warning via sensor fusion

    NASA Astrophysics Data System (ADS)

    Flaherty, Michael; Pritchett, Daniel; Cothren, Brian; Schwaiger, James

    2011-05-01

    Torch Technologies Inc., is actively involved in chemical sensor networking and data fusion via multi-year efforts with Dugway Proving Ground (DPG) and the Defense Threat Reduction Agency (DTRA). The objective of these efforts is to develop innovative concepts and advanced algorithms that enhance our national Chemical Warfare (CW) test and warning capabilities via the fusion of traditional and non-traditional CW sensor data. Under Phase I, II, and III Small Business Innovative Research (SBIR) contracts with DPG, Torch developed the Advanced Chemical Release Evaluation System (ACRES) software to support non real-time CW sensor data fusion. Under Phase I and II SBIRs with DTRA in conjunction with the Edgewood Chemical Biological Center (ECBC), Torch is using the DPG ACRES CW sensor data fuser as a framework from which to develop the Cloud state Estimation in a Networked Sensor Environment (CENSE) data fusion system. Torch is currently developing CENSE to implement and test innovative real-time sensor network based data fusion concepts using CW and non-CW ancillary sensor data to improve CW warning and detection in tactical scenarios.

  17. A Hole in the Weather Warning System.

    NASA Astrophysics Data System (ADS)

    Wood, Vincent T.; Weisman, Robert A.

    2003-02-01

    lack of text information. These problems had forced deaf and hard of hearing people to rely on looking at the sky or having hearing people alert them as their primary methods of receiving emergency information. These problems are documented through the use of a survey of 277 deaf and hard of hearing people in Minnesota and Oklahoma as well as specific examples.During the last two years, some progress has been made to "close this hole" in the weather warning system. The Federal Communications Commission has approved new rules, requiring that all audio emergency information provided by television stations, satellite, and cable operators must also be provided visually. In addition, the use of new technology such as pager systems, weather radios adapted for use by those with special needs, the Internet, and satellite warning systems have allowed deaf and hard of hearing people to have more access to emergency information.In this article, these improvements are documented but continuing problems and possible solutions are also listed.

  18. Flood Warning and Forecasting System in Slovakia

    NASA Astrophysics Data System (ADS)

    Leskova, Danica

    2016-04-01

    In 2015, it finished project Flood Warning and Forecasting System (POVAPSYS) as part of the flood protection in Slovakia till 2010. The aim was to build POVAPSYS integrated computerized flood forecasting and warning system. It took a qualitatively higher level of output meteorological and hydrological services in case of floods affecting large territorial units, as well as local flood events. It is further unfolding demands on performance and coordination of meteorological and hydrological services, troubleshooting observation, evaluation of data, fast communication, modeling and forecasting of meteorological and hydrological processes. Integration of all information entering and exiting to and from the project POVAPSYS provides Hydrological Flood Forecasting System (HYPOS). The system provides information on the current hydrometeorological situation and its evolution with the generation of alerts and notifications in case of exceeding predefined thresholds. HYPOS's functioning of the system requires flawless operability in critical situations while minimizing the loss of its key parts. HYPOS is a core part of the project POVAPSYS, it is a comprehensive software solutions based on a modular principle, providing data and processed information including alarms, in real time. In order to achieve full functionality of the system, in proposal, we have put emphasis on reliability, robustness, availability and security.

  19. Early Warning System Ghana: how to successfully implement a disaster early warning system in a data scarce region

    NASA Astrophysics Data System (ADS)

    Udo, Job; Jungermann, Nicole

    2016-04-01

    Ghana is a country frequently struck by natural disasters like floods and droughts. Timely warning or detection of such disasters will mitigate the negative impact on lives and property. However, local data and monitoring systems necessary to provide such a warning are hardly available. The availability and improvement of internet, mobile phones and satellites has provided new possibilities for disaster warning systems in data scarce regions such as Ghana. Our presentation describes the development of an early warning system (EWS) in Ghana completely based on satellite based open data. The EWS provides a flood or drought hazard warning on sub-catchment level and links the warning to a more detailed flood or drought risk map, to enable the disaster coordinator to send warnings or relieve more efficiently to areas that have the highest risk. This is especially relevant because some areas for which the system is implemented are very remote. The system is developed and tested to be robust and operational especially in remote areas. This means that the necessary information is also available under limited internet conditions and not dependent on local computer facilities. In many rural areas in Ghana communities rely on indigenous knowledge when it comes to flood or drought disaster forecasting. The EWS has a feature that allows indigenous knowledge indicators to be taken into account in the warning and makes easy comparison possible with the satellite based warnings.

  20. Nowcasting, warning, mitigation, and documentation of hail storms in Styria, Austria

    NASA Astrophysics Data System (ADS)

    Teschl, Franz; Teschl, Reinhard; Paulitsch, Helmut; Randeu, Walter L.

    2013-04-01

    The South-East of the Austrian province of Styria is a hail-hotspot. Typically on more than 50 days in summer hail warnings are released. Since decades, hail mitigation actions are carried out by means of specially equipped aircraft seeding 'suspicious' clouds with silver-iodide generators. In the year 2009, a project was started with the goal to document hail events and to increase the efficiency of hail finding measures. Since decades, the weather situation is observed in this region by the Austrian C-band weather radar network that provides every five minutes updated 3D reflectivity and velocity measurements with a resolution of 1 km. In 2009, the aircraft used for cloud seeding have been equipped with GPS sensors and tablet PCs. As a consequence, the position of the aircraft is accessible in close to real time and can be marked in the weather radar images. Further, the aircraft pilots have access to the current weather radar images. This idea guarantees a two-way information exchange. On the one hand, the pilots get a full picture of the overall weather situation. On the other hand, it can be documented what cloud cells the experienced aircraft pilots regarded as critical and when and where they chose to seed. Since the project started, aircraft seeding has been documented on more than 150 days. This study analyzes convective storms as they were tracked with the weather radar during their life cycle - from the origin to the collapse. Both categories of cells, seeded and unseeded ones, have been analyzed. The duration, the path-length of the track over ground, the vertical profile, the zero-degree isotherm, as well as the precipitation rate have been extracted. These datasets will allow the evaluation of forecast models for convective storms. It was further evaluated if the seeded convective storms met standardized seeding criteria. A long term perspective of the ongoing project is a scientific analysis of the effects of the hail suppression measures based on

  1. Electromagnetic resonant modes of dielectric sphere bilayers

    SciTech Connect

    Andueza, A. Pérez-Conde, J.; Sevilla, J.

    2015-05-28

    Sphere bilayers have been proposed as promising structures for electromagnetic management in photonic crystal devices. These arrangements are made of two intertwined subsets of spheres of different size and refractive index, one subset filling the interstitial sites of the other. We present a systematic study of the electromagnetic resonant modes of the bilayers, in comparison with those of the constituent subsets of spheres. Three samples were built with glass and Teflon spheres and their transmission spectra measured in the microwave range (10–25 GHz). Simulations with finite integration time-domain method are in good agreement with experiments. Results show that the bilayer presents the same resonances as one of the subsets but modified by the presence of the other in its resonant frequencies and in the electric field distributions. As this distortion is not very large, the number of resonances in a selected spectral region is determined by the dominant subset. The degree of freedom that offers the bilayer could be useful to fine tune the resonances of the structure for different applications. A map of modes useful to guide this design is also presented. Scale invariance of Maxwell equations allows the translation of these results in the microwave range to the visible region; hence, some possible applications are discussed in this framework.

  2. Metal-Matrix/Hollow-Ceramic-Sphere Composites

    NASA Technical Reports Server (NTRS)

    Baker, Dean M.

    2011-01-01

    A family of metal/ceramic composite materials has been developed that are relatively inexpensive, lightweight alternatives to structural materials that are typified by beryllium, aluminum, and graphite/epoxy composites. These metal/ceramic composites were originally intended to replace beryllium (which is toxic and expensive) as a structural material for lightweight mirrors for aerospace applications. These materials also have potential utility in automotive and many other terrestrial applications in which there are requirements for lightweight materials that have high strengths and other tailorable properties as described below. The ceramic component of a material in this family consists of hollow ceramic spheres that have been formulated to be lightweight (0.5 g/cm3) and have high crush strength [40.80 ksi (.276.552 MPa)]. The hollow spheres are coated with a metal to enhance a specific performance . such as shielding against radiation (cosmic rays or x rays) or against electromagnetic interference at radio and lower frequencies, or a material to reduce the coefficient of thermal expansion (CTE) of the final composite material, and/or materials to mitigate any mismatch between the spheres and the matrix metal. Because of the high crush strength of the spheres, the initial composite workpiece can be forged or extruded into a high-strength part. The total time taken in processing from the raw ingredients to a finished part is typically 10 to 14 days depending on machining required.

  3. The Sphere of Women in Colonial America.

    ERIC Educational Resources Information Center

    Cook, Robert

    This project is a unit of six lessons designed to study and understand the roles and expectations of women in the colonial period. The unit provides an historical perspective on those expectations, examines how both men and women viewed the sphere of women, and how enlightened thought on this topic began to emerge during this revolutionary time.…

  4. Spheres: from Ground Development to ISS Operations

    NASA Technical Reports Server (NTRS)

    Katterhagen, A.

    2016-01-01

    SPHERES (Synchronized Position Hold Engage and Reorient Experimental Satellites) is an internal International Space Station (ISS) Facility that supports multiple investigations for the development of multi-spacecraft and robotic control algorithms. The SPHERES National Lab Facility aboard ISS is managed and operated by NASA Ames Research Center (ARC) at Moffett Field California. The SPHERES Facility on ISS consists of three self-contained eight-inch diameter free-floating satellites which perform the various flight algorithms and serve as a platform to support the integration of experimental hardware. SPHERES has served to mature the adaptability of control algorithms of future formation flight missions in microgravity (6 DOF (Degrees of Freedom) / long duration microgravity), demonstrate key close-proximity formation flight and rendezvous and docking maneuvers, understand fault diagnosis and recovery, improve the field of human telerobotic operation and control, and lessons learned on ISS have significant impact on ground robotics, mapping, localization, and sensing in three-dimensions - among several other areas of study.

  5. Experimentation on recurrent sphere collision with Audacity

    NASA Astrophysics Data System (ADS)

    Muradoglu, Murat; Ng, Enoch Ming Wei; Ng, Tuck Wah

    2014-11-01

    Under the theme of collisions that occur repeatedly, we conducted easy and inexpensive experiments of rebounding spheres and Newton’s cradle with two spheres to determine the coefficients of restitution using the sound record feature in modern laptops and a free and open source software called Audacity. In the rebounding sphere experiment, the coefficients of restitution of the golf and ping pong balls used were found to be 0.727 ± 0.025 and 0.816 ± 0.041 respectively. With the Netwon’s cradle experiment, the coefficient of restitution of two steel sphere balls was found to be 0.987 ± 0.003. The contrasts in the results obtained from both experiments permit the operational principles of a pendulum to be emphasized, and engagements to be made to consider the transfer of kinetic energy in the form of vibrational energy of the bodies’ constituents. Using a one-dimensional two-mass model with spring and damper linkages to account for harmonic motions that occur during impact, we found it possible to perform a simple analysis to account for this, and how it can be linked to high energy transfer modes such as the phenomenon of resonance and impedance matching.

  6. Propulsion of a two-sphere swimmer

    NASA Astrophysics Data System (ADS)

    Klotsa, Daphne; Baldwin, Kyle; Hill, Richard; Bowley, Roger; Swift, Michael

    We describe experiments and simulations demonstrating the propulsion of a neutrally-buoyant macroscopic swimming robot that consists of a pair of spheres attached by a spring, immersed in a vibrating fluid. The vibration of the fluid induces relative motion of the spheres which, for sufficiently large amplitudes, can lead to motion of the center of mass of the two spheres. We find that the swimming speed obtained from both experiment and simulation agree and collapse onto a single curve if plotted as a function of the streaming Reynolds number, suggesting that the propulsion is related to streaming flows. There appears to be a critical onset value of the streaming Reynolds number for swimming to occur. We observe a change in the streaming flows as the Reynolds number increases, from that generated by two independent oscillating spheres to a collective flow pattern around the swimmer as a whole. The mechanism for swimming is traced to a strengthening of a jet of fluid in the wake of the swimmer.

  7. Steel Spheres and Skydiver--Terminal Velocity

    ERIC Educational Resources Information Center

    Costa Leme, J.; Moura, C.; Costa, Cintia

    2009-01-01

    This paper describes the use of open source video analysis software in the study of the relationship between the velocity of falling objects and time. We discuss an experiment in which a steel sphere falls in a container filled with two immiscible liquids. The motion is similar to that of a skydiver falling through air.

  8. Properties of a Two-Sphere Singularity

    NASA Astrophysics Data System (ADS)

    Konkowski, Deborah A.; Helliwell, Thomas M.

    2015-01-01

    Recently Böhmer and Lobo have shown that a metric due to Florides can be extended to reveal a classical singularity that has the form of a two-sphere. Here we discuss and expand on the classical singularity properties and then show the classical singularity is not healed by a quantum analysis.

  9. Propulsion of a Two-Sphere Swimmer.

    PubMed

    Klotsa, Daphne; Baldwin, Kyle A; Hill, Richard J A; Bowley, R M; Swift, Michael R

    2015-12-11

    We describe experiments and simulations demonstrating the propulsion of a neutrally buoyant swimmer that consists of a pair of spheres attached by a spring, immersed in a vibrating fluid. The vibration of the fluid induces relative motion of the spheres which, for sufficiently large amplitudes, can lead to motion of the center of mass of the two spheres. We find that the swimming speed obtained from both experiment and simulation agree and collapse onto a single curve if plotted as a function of the streaming Reynolds number, suggesting that the propulsion is related to streaming flows. There appears to be a critical onset value of the streaming Reynolds number for swimming to occur. We observe a change in the streaming flows as the Reynolds number increases, from that generated by two independent oscillating spheres to a collective flow pattern around the swimmer as a whole. The mechanism for swimming is traced to a strengthening of a jet of fluid in the wake of the swimmer.

  10. Life in the E-Sphere.

    ERIC Educational Resources Information Center

    Pelton, Joseph N.

    2002-01-01

    Discusses the survival of the human race in the Third Millennium. Considers environmental issues; shifting from a focus on economic growth to human development; the rate of technological change; the e-sphere, which goes beyond a global village to a global brain; technology in education and in health care; and educational reform. (LRW)

  11. Some analytical models of radiating collapsing spheres

    SciTech Connect

    Herrera, L.; Di Prisco, A; Ospino, J.

    2006-08-15

    We present some analytical solutions to the Einstein equations, describing radiating collapsing spheres in the diffusion approximation. Solutions allow for modeling physical reasonable situations. The temperature is calculated for each solution, using a hyperbolic transport equation, which permits to exhibit the influence of relaxational effects on the dynamics of the system.

  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. 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....

  14. 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...

  15. 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...

  16. 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....

  17. 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...

  18. 19 CFR 122.64 - Other aircraft.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 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...

  19. 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.

  20. Domain-wall supergravities from sphere reduction

    NASA Astrophysics Data System (ADS)

    Cvetič , M.; Liu, James T.; Lü, H.; Pope, C. N.

    1999-10-01

    Kaluza-Klein sphere reductions of supergravities that admit Ads × Sphere vacuum solutions are believed to be consistent. The examples include the S4 and S7 reductions of eleven-dimensional supergravity, and the S5 reduction of ten-dimensional type IIB supergravity . In this paper we provide evidence that sphere reductions of supergravities that admit instead Domain-wallxSphere vacuum solutions are also consistent, where the background can be viewed as the near-horizon structure of a dilatonic p-brane of the theory. The resulting lower-dimensional theory is a gauged supergravity that admits a domain wall, rather than AdS, as a vacuum solution. We illustrate this consistency by taking the singular limits of certain modulus parameters, for which the original Sn compactifying spheres ( n = 4, 5 or 7) becomes Sp × Rq, with p = n - q < n. The consistency of the S4, S7 reductions then implies the consistency of the S p reductions of the lower-dimensional supergravities. In particular, we obtain explicit non-linear ansätze for the S3 reduction of type IIA and heterotic supergravities, restricting to the U(1) 2 subgroup of the SO(4) gauge group of S3. We also study the black-hole solutions in the lower-dimensional gauged supergravities with domain-wall backgrounds. We find new domain-wall black holes which are not the singular-modulus limits of the AdS black holes of the original theories, and we obtain their Killing spinors.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Fabrication of cylindrical, microcellular foam-filled targets, containing aluminum spheres, for sphere drag experiments

    SciTech Connect

    Falconer, J.W.; Nazarov, W. ); Horsfield, C.J.; Sutton, D.W.; Rothman, S.D.; Freeman, N.J. )

    1994-09-01

    Hollow cylindrical fusion targets of 200--300 [mu]m diam and 500--600 [mu]m length, were fabricated and fitted at one end with a metallic ablator plate. The cylinders were then filled with a solution of polyfunctional acrylate monomer, which was subsequently polymerized to a gel using ultraviolet initiated polymerization. Either one or two aluminum spheres of diameter between 10 and 30 [mu]m were placed in the gel at defined locations, before the gel was precipitated to give, on drying by critical point dryer, a foam of the required density (about 100 mg cm[sup [minus]3]). The final targets had the sphere or spheres embedded in the foam at specified locations. Several techniques for placing the spheres were examined and the relative merits of the techniques are discussed.

  6. Simulation of rotary-drum and repose tests for frictional spheres and rigid sphere clusters

    SciTech Connect

    Walton, O.R.; Braun, R.L.

    1993-11-01

    The effects of rotation rate and interparticle friction on the bulk flow behavior in rotating horizontal cylinders are studied via particle-dynamic simulations. Assemblies of inelastic, frictional spheres and rigid sphere clusters are utilized, and rotation rates from quasistatic to centrifuging are examined. Flow phenomena explored include size segregation, avalanching, slumping and centrifuging. Simulated drum flows with two sizes of frictional spheres showed very rapid segregation of species perpendicular to the drum axis; however, simulations of up to 10 revolutions, utilizing periodic-boundary ends, did not exhibit the experimentally observed axial segregation into stripes. Angles of repose for uniform-sized spheres in slowly rotating cylinders varied from 13 to 31 degrees as the friction coefficient varied from 0.02 to 1.0. For simulated rotation rates higher than the threshold to obtain uniform flow conditions, the apparent angle of repose increases as the rotation rats increases, consistent with experiments. Also, simulations with rigid clusters of 4 spheres in a tetrahedral shape or 8 spheres in a cubical arrangement, demonstrate that particle shape strongly influences the repose angle. Simulations of cubical 8-sphere clusters, with a surface coefficient of friction of 0.1, produced apparent angles of repose exceeding 35 degrees, compared to 23 degrees for assemblies of single spheres interacting with the same force model parameters. Centrifuging flows at very high rotation rates exist as stationary beds moving exactly as the outer rotating wall. At somewhat slower speeds the granular bed remains in contact with the wall but exhibits surface sliding down the rising inner bed surface, moving a short distance on each revolution. At still slower speeds particles rain from the surface of the upper half of the rotating bed.

  7. 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.

  8. 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.

  9. Aircraft identification experience

    NASA Technical Reports Server (NTRS)

    Iliff, K. W.

    1979-01-01

    Important aspects of estimating the unknown coefficients of the aircraft equations of motion from dynamic flight data are presented. The primary topic is the application of the maximum likelihood estimation technique. Basic considerations that must be addressed in the estimation of stability and control derivatives from conventional flight maneuvers are discussed. Some complex areas of estimation (such as estimation in the presence of atmospheric turbulence, estimation of acceleration derivatives, and analysis of maneuvers where both kinematic and aerodynamic coupling are present) are also discussed.

  10. 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.

  11. 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.

  12. CDC Warns of Dangers of Plastic Surgery in Dominican Republic

    MedlinePlus

    ... gov/news/fullstory_159884.html CDC Warns of Dangers of Plastic Surgery in Dominican Republic Report details cases of U.S. women who developed disfiguring infections after procedures there To ... health officials are warning about the dangers of "medical tourism" after at least 18 women ...

  13. Warning Signs for Suicide: Theory, Research, and Clinical Applications

    ERIC Educational Resources Information Center

    Rudd, M. David; Berman, Alan L.; Joiner, Thomas E., Jr.; Nock, Matthew K.; Silverman, Morton M.; Mandrusiak, Michael; Van Orden, Kimberly; Witte, Tracy

    2006-01-01

    The current article addresses the issue of warning signs for suicide, attempting to differentiate the construct from risk factors. In accordance with the characteristic features discussed, a consensus set of warning signs identified by the American Association of Suicidology working group are presented, along with a discussion of relevant clinical…

  14. Linking the evolution and form of warning coloration in nature

    PubMed Central

    Stevens, Martin; Ruxton, Graeme D.

    2012-01-01

    Many animals are toxic or unpalatable and signal this to predators with warning signals (aposematism). Aposematic appearance has long been a classical system to study predator–prey interactions, communication and signalling, and animal behaviour and learning. The area has received considerable empirical and theoretical investigation. However, most research has centred on understanding the initial evolution of aposematism, despite the fact that these studies often tell us little about the form and diversity of real warning signals in nature. In contrast, less attention has been given to the mechanistic basis of aposematic markings; that is, ‘what makes an effective warning signal?’, and the efficacy of warning signals has been neglected. Furthermore, unlike other areas of adaptive coloration research (such as camouflage and mate choice), studies of warning coloration have often been slow to address predator vision and psychology. Here, we review the current understanding of warning signal form, with an aim to comprehend the diversity of warning signals in nature. We present hypotheses and suggestions for future work regarding our current understanding of several inter-related questions covering the form of warning signals and their relationship with predator vision, learning, and links to broader issues in evolutionary ecology such as mate choice and speciation. PMID:22113031

  15. 49 CFR 393.87 - Warning flags on projecting loads.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... than 102 mm (4 inches) or more than 1,219 mm (4 feet) beyond the rear must have the extremities of the load marked with red or orange fluorescent warning flags. Each warning flag must be at least 457 mm...

  16. 49 CFR 393.87 - Warning flags on projecting loads.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... than 102 mm (4 inches) or more than 1,219 mm (4 feet) beyond the rear must have the extremities of the load marked with red or orange fluorescent warning flags. Each warning flag must be at least 457 mm...

  17. 47 CFR 17.45 - Temporary warning lights.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Temporary warning lights. 17.45 Section 17.45... warning lights. During construction of an antenna structure, for which red obstruction lighting is required, at least two 116- or 125-watt lamps (A21/TS) enclosed in aviation red obstruction light...

  18. 47 CFR 17.45 - Temporary warning lights.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Temporary warning lights. 17.45 Section 17.45... warning lights. During construction of an antenna structure, for which red obstruction lighting is required, at least two 116- or 125-watt lamps (A21/TS) enclosed in aviation red obstruction light...

  19. Feasibility study of using satellites for a disaster warning system

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The development of requirements for the Disaster Warning System (DWS) was investigated in relation to the National Weather Service. Conceptual communication traffic flow patterns for the future of the NWS are studied to determine the impact of the DWS on the MWS. The planned warning systems, and satellite communications are discussed along with data collection, and communication services.

  20. 14 CFR 125.187 - Landing gear: Aural warning device.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Landing gear: Aural warning device. 125.187... Requirements § 125.187 Landing gear: Aural warning device. (a) Except for airplanes that comply with the requirements of § 25.729 of this chapter on or after January 6, 1992, each airplane must have a landing...

  1. 14 CFR 125.187 - Landing gear: Aural warning device.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Landing gear: Aural warning device. 125.187... Requirements § 125.187 Landing gear: Aural warning device. (a) Except for airplanes that comply with the requirements of § 25.729 of this chapter on or after January 6, 1992, each airplane must have a landing...

  2. 14 CFR 125.187 - Landing gear: Aural warning device.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Landing gear: Aural warning device. 125.187... Requirements § 125.187 Landing gear: Aural warning device. (a) Except for airplanes that comply with the requirements of § 25.729 of this chapter on or after January 6, 1992, each airplane must have a landing...

  3. 14 CFR 125.187 - Landing gear: Aural warning device.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Landing gear: Aural warning device. 125.187... Requirements § 125.187 Landing gear: Aural warning device. (a) Except for airplanes that comply with the requirements of § 25.729 of this chapter on or after January 6, 1992, each airplane must have a landing...

  4. 14 CFR 125.187 - Landing gear: Aural warning device.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Landing gear: Aural warning device. 125.187... Requirements § 125.187 Landing gear: Aural warning device. (a) Except for airplanes that comply with the requirements of § 25.729 of this chapter on or after January 6, 1992, each airplane must have a landing...

  5. Perceptions and Expected Immediate Reactions to Tornado Warning Polygons

    NASA Astrophysics Data System (ADS)

    Lindell, M. K.; Huang, S. K.; Wei, H. L.; Samuelson, C. D.

    2015-12-01

    To provide people with more specific information about tornado threats, the National Weather Service has replaced its county-wide warnings with smaller warning polygons that more specifically indicate the risk area. However, tornado warning polygons do not have a standardized definition regarding tornado strike probabilities (ps) so it is unclear how warning recipients interpret them. To better understand this issue, 155 participants responded to 15 hypothetical warning polygons. After viewing each polygon, they rated the likelihood of a tornado striking their location and the likelihood that they would take nine different response actions ranging from continuing normal activities to getting in a car and driving somewhere safer. The results showed participants inferred that the ps was highest at the polygon's centroid, lower just inside the edges of the polygon, still lower (but not zero) just outside the edges of the polygon, and lowest in locations beyond that. Moreover, higher ps values were associated with lower expectations of continuing normal activities and higher expectations of seeking information from social sources (but not environmental cues) and higher expectations of seeking shelter (but not evacuating in their cars). These results indicate that most people make some errors in their ps judgments but are likely to respond appropriately to the ps they infer from the warning polygons. Overall, the findings from this study and other research can help meteorologists to better understand how people interpret the uncertainty associated with warning polygons and, thus, improve tornado warning systems.

  6. Linking the evolution and form of warning coloration in nature.

    PubMed

    Stevens, Martin; Ruxton, Graeme D

    2012-02-01

    Many animals are toxic or unpalatable and signal this to predators with warning signals (aposematism). Aposematic appearance has long been a classical system to study predator-prey interactions, communication and signalling, and animal behaviour and learning. The area has received considerable empirical and theoretical investigation. However, most research has centred on understanding the initial evolution of aposematism, despite the fact that these studies often tell us little about the form and diversity of real warning signals in nature. In contrast, less attention has been given to the mechanistic basis of aposematic markings; that is, 'what makes an effective warning signal?', and the efficacy of warning signals has been neglected. Furthermore, unlike other areas of adaptive coloration research (such as camouflage and mate choice), studies of warning coloration have often been slow to address predator vision and psychology. Here, we review the current understanding of warning signal form, with an aim to comprehend the diversity of warning signals in nature. We present hypotheses and suggestions for future work regarding our current understanding of several inter-related questions covering the form of warning signals and their relationship with predator vision, learning, and links to broader issues in evolutionary ecology such as mate choice and speciation.

  7. 40 CFR 82.108 - Placement of warning statement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 18 2014-07-01 2014-07-01 false Placement of warning statement. 82.108 Section 82.108 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE The Labeling of Products Using Ozone-Depleting Substances § 82.108 Placement of warning statement....

  8. 46 CFR 108.626 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Carbon dioxide warning signs. 108.626 Section 108.626... AND EQUIPMENT Equipment Markings and Instructions § 108.626 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or...

  9. 46 CFR 97.37-11 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Carbon dioxide warning signs. 97.37-11 Section 97.37-11... OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-11 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or...

  10. 46 CFR 108.626 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Carbon dioxide warning signs. 108.626 Section 108.626... AND EQUIPMENT Equipment Markings and Instructions § 108.626 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or...

  11. 46 CFR 97.37-11 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Carbon dioxide warning signs. 97.37-11 Section 97.37-11... OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-11 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or...

  12. 46 CFR 78.47-11 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Carbon dioxide warning signs. 78.47-11 Section 78.47-11... Fire and Emergency Equipment, Etc. § 78.47-11 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or any space into...

  13. 46 CFR 196.37-8 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Carbon dioxide warning signs. 196.37-8 Section 196.37-8... Markings for Fire and Emergency Equipment, etc. § 196.37-8 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or any space...

  14. 46 CFR 78.47-11 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 3 2014-10-01 2014-10-01 false Carbon dioxide warning signs. 78.47-11 Section 78.47-11... Fire and Emergency Equipment, Etc. § 78.47-11 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or any space into...

  15. 46 CFR 131.817 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Carbon dioxide warning signs. 131.817 Section 131.817... Markings for Fire Equipment and Emergency Equipment § 131.817 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or...

  16. 46 CFR 78.47-11 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 3 2013-10-01 2013-10-01 false Carbon dioxide warning signs. 78.47-11 Section 78.47-11... Fire and Emergency Equipment, Etc. § 78.47-11 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or any space into...

  17. 46 CFR 108.626 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Carbon dioxide warning signs. 108.626 Section 108.626... AND EQUIPMENT Equipment Markings and Instructions § 108.626 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or...

  18. 46 CFR 196.37-8 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Carbon dioxide warning signs. 196.37-8 Section 196.37-8... Markings for Fire and Emergency Equipment, etc. § 196.37-8 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or any space...

  19. 46 CFR 131.817 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Carbon dioxide warning signs. 131.817 Section 131.817... Markings for Fire Equipment and Emergency Equipment § 131.817 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or...

  20. 46 CFR 97.37-11 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Carbon dioxide warning signs. 97.37-11 Section 97.37-11... OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-11 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space protected by carbon dioxide systems, or...