forward-looking interferometer fli: Topics by Science.gov

Sample records for forward-looking interferometer fli

Experimental Validation of a Forward Looking Interferometer for Detection of Clear Air Turbulence due to Mountain Waves

NASA Technical Reports Server (NTRS)

Schaffner, Philip R.; Daniels, Taumi S.; West, Leanne L.; Gimmestad, Gary G.; Lane, Sarah E.; Burdette, Edward M.; Smith, William L.; Kireev, Stanislav; Cornman, Larry; Sharman, Robert D.

2012-01-01

The Forward-Looking Interferometer (FLI) is an airborne sensor concept for detection and estimation of potential atmospheric hazards to aircraft. The FLI concept is based on high-resolution Infrared Fourier Transform Spectrometry technologies that have been developed for satellite remote sensing. The FLI is being evaluated for its potential to address multiple hazards, during all phases of flight, including clear air turbulence, volcanic ash, wake vortices, low slant range visibility, dry wind shear, and icing. In addition, the FLI is being evaluated for its potential to detect hazardous runway conditions during landing, such as wet or icy asphalt or concrete. The validation of model-based instrument and hazard simulation results is accomplished by comparing predicted performance against empirical data. In the mountain lee wave data collected in the previous FLI project, the data showed a damped, periodic mountain wave structure. The wave data itself will be of use in forecast and nowcast turbulence products such as the Graphical Turbulence Guidance and Graphical Turbulence Guidance Nowcast products. Determining how turbulence hazard estimates can be derived from FLI measurements will require further investigation.
Airborne Forward-Looking Interferometer for the Detection of Terminal-Area Hazards

NASA Technical Reports Server (NTRS)

West, Leanne; Gimmestad, Gary; Lane, Sarah; Smith, Bill L.; Kireev, Stanislav; Daniels, Taumi S.; Cornman, Larry; Sharman, Bob

2014-01-01

The Forward Looking Interferometer (FLI) program was a multi-year cooperative research effort to investigate the use of imaging radiometers with high spectral resolution, using both modeling/simulation and field experiments, along with sophisticated data analysis techniques that were originally developed for analysis of data from space-based radiometers and hyperspectral imagers. This investigation has advanced the state of knowledge in this technical area, and the FLI program developed a greatly improved understanding of the radiometric signal strength of aviation hazards in a wide range of scenarios, in addition to a much better understanding of the real-world functionality requirements for hazard detection instruments. The project conducted field experiments on three hazards (turbulence, runway conditions, and wake vortices) and analytical studies on several others including volcanic ash, reduced visibility conditions, in flight icing conditions, and volcanic ash.
Hazard Detection Analysis for a Forward-Looking Interferometer

NASA Technical Reports Server (NTRS)

West, Leanne; Gimmestad, Gary; Herkert, Ralph; Smith, William L.; Kireev, Stanislav; Schaffner, Philip R.; Daniels, Taumi S.; Cornman, Larry B.; Sharman, Robert; Weekley, Andrew;

2010-01-01

The Forward-Looking Interferometer (FLI) is a new instrument concept for obtaining the measurements required to alert flight crews to potential weather hazards to safe flight. To meet the needs of the commercial fleet, such a sensor should address multiple hazards to warrant the costs of development, certification, installation, training, and maintenance. The FLI concept is based on high-resolution Infrared Fourier Transform Spectrometry (FTS) technologies that have been developed for satellite remote sensing. These technologies have also been applied to the detection of aerosols and gases for other purposes. The FLI concept is being evaluated for its potential to address multiple hazards including clear air turbulence (CAT), volcanic ash, wake vortices, low slant range visibility, dry wind shear, and icing during all phases of flight (takeoff, cruise, and landing). The research accomplished in this second phase of the FLI project was in three major areas: further sensitivity studies to better understand the potential capabilities and requirements for an airborne FLI instrument, field measurements that were conducted in an effort to provide empirical demonstrations of radiometric hazard detection, and theoretical work to support the development of algorithms to determine the severity of detected hazards

Applications of a Forward-Looking Interferometer for the On-board Detection of Aviation Weather Hazards

NASA Technical Reports Server (NTRS)

West, Leanne; Gimmestad, Gary; Smith, William; Kireev, Stanislav; Cornman, Larry B.; Schaffner, Philip R.; Tsoucalas, George

2008-01-01

The Forward-Looking Interferometer (FLI) is a new instrument concept for obtaining measurements of potential weather hazards to alert flight crews. The FLI concept is based on high-resolution Infrared (IR) Fourier Transform Spectrometry (FTS) technologies that have been developed for satellite remote sensing, and which have also been applied to the detection of aerosols and gases for other purposes. It is being evaluated for multiple hazards including clear air turbulence (CAT), volcanic ash, wake vortices, low slant range visibility, dry wind shear, and icing, during all phases of flight. Previous sensitivity and characterization studies addressed the phenomenology that supports detection and mitigation by the FLI. Techniques for determining the range, and hence warning time, were demonstrated for several of the hazards, and a table of research instrument parameters was developed for investigating all of the hazards discussed above. This work supports the feasibility of detecting multiple hazards with an FLI multi-hazard airborne sensor, and for producing enhanced IR images in reduced visibility conditions; however, further research must be performed to develop a means to estimate the intensities of the hazards posed to an aircraft and to develop robust algorithms to relate sensor measurables to hazard levels. In addition, validation tests need to be performed with a prototype system.
Hyperspectral Image Turbulence Measurements of the Atmosphere

NASA Technical Reports Server (NTRS)

Lane, Sarah E.; West, Leanne L.; Gimmestad, Gary G.; Kireev, Stanislav; Smith, William L., Sr.; Burdette, Edward M.; Daniels, Taumi; Cornman, Larry

2012-01-01

A Forward Looking Interferometer (FLI) sensor has the potential to be used as a means of detecting aviation hazards in flight. One of these hazards is mountain wave turbulence. The results from a data acquisition activity at the University of Colorado s Mountain Research Station will be presented here. Hyperspectral datacubes from a Telops Hyper-Cam are being studied to determine if evidence of a turbulent event can be identified in the data. These data are then being compared with D&P TurboFT data, which are collected at a much higher time resolution and broader spectrum.
Looking Back and Looking Forward: Reprising the Promise and Predicting the Future of Formation Flying and Spaceborne GPS Navigation Systems

NASA Technical Reports Server (NTRS)

Bauer, Frank H.; Dennehy, Neil

2015-01-01

A retrospective consideration of two 15-year old Guidance, Navigation and Control (GN&C) technology 'vision' predictions will be the focus of this paper. A look back analysis and critique of these late 1990s technology roadmaps out-lining the future vision, for two then nascent, but rapidly emerging, GN&C technologies will be performed. Specifically, these two GN&C technologies were: 1) multi-spacecraft formation flying and 2) the spaceborne use and exploitation of global positioning system (GPS) signals to enable formation flying. This paper reprises the promise of formation flying and spaceborne GPS as depicted in the cited 1999 and 1998 papers. It will discuss what happened to cause that promise to be mostly unfulfilled and the reasons why the envisioned formation flying dream has yet to become a reality. The recent technology trends over the past few years will then be identified and a renewed government interest in spacecraft formation flying/cluster flight will be highlighted. The authors will conclude with a reality-tempered perspective, 15 years after the initial technology roadmaps were published, predicting a promising future of spacecraft formation flying technology development over the next decade.
Relative merits of reactive and forward-look detection for wind-shear encounters during landing approach for various microburst escape strategies

NASA Technical Reports Server (NTRS)

Hinton, David A.

1990-01-01

The goal was to quantify the benefits of airborne forward-look windshear detection and to develop and test a candidate set of strategies for recovery from inadvertent microburst encounters during the landing approach, given the utilization of both reactive-only and forward-look windshear detection. Candidate strategies were developed and evaluated using a non-piloted simulation consisting of a simple point-mass performance model of a transport-category airplane flying through an analytical microburst model. The results indicate that the factor which most strongly effects a microburst recovery is the time at which the recovery is initiated. Forward-look alerts given 10 seconds prior to microburst entry permitted recoveries to be made with negligible altitude loss. The results also show that no single microburst scenario can be used to evaluate the relative merits of various recovery strategies. The type of alert used to initiate the recovery (reactive or forward-look) and the altitude of the microburst encounter had an effect on the type of recovery strategy that performed best. These factors may have serious implications for the design and certification of windshear systems.
The Path to Interferometry in Space

NASA Technical Reports Server (NTRS)

Rinehart, S. A.; Savini, G.; Holland, W.; Absil, O.; Defrere, D.; Spencer, L.; Leisawitz, D.; Rizzo, M.; Juanola-Parramon, R.; Mozurkewich, D.

2016-01-01

For over two decades, astronomers have considered the possibilities for interferometry in space. The first of these missions was the Space Interferometry Mission (SIM), but that was followed by missions for studying exoplanets (e.g Terrestrial Planet Finder, Darwin), and then far-infrared interferometers (e.g. the Space Infrared Interferometric Telescope, the Far-Infrared Interferometer). Unfortunately, following the cancellation of SIM, the future for space-based interferometry has been in doubt, and the interferometric community needs to reevaluate the path forward. While interferometers have strong potential for scientific discovery, there are technological developments still needed, and continued maturation of techniques is important for advocacy to the broader astronomical community. We review the status of several concepts for space-based interferometry, and look for possible synergies between missions oriented towards different science goals.
Dim star fringe stabilization demonstration using pathlength feed-forward on the SIM testbed 3 (STB3)

NASA Astrophysics Data System (ADS)

Goullioud, Renaud; Alvarez-Salazar, Oscar S.; Nemati, Bijan

2003-02-01

Future space-based optical interferometers such as the Space Interferometer Mission require fringe stabilization to the level of nanometers in order to produce astrometric data at the micro-arc-second level. Even the best attitude control system available to date will not be able to stabilize the attitude of a several thousand pound spacecraft to a few milli-arc-seconds. Active pathlength control is usually implemented to compensate for attitude drift of the spacecraft. This issue has been addressed in previous experiments while tracking bright stars. In the case of dim stars, as the sensor bandwidth falls below one hertz, feedback control will not provide sufficient rejection. However, stabilization of the fringes from a dim-star down to the nanometer level can be done open loop using information from additional interferometers looking at bright guide stars. The STB3 testbed developed at the Jet Propulsion Laboratory features three optical interferometers sharing a common baseline, dynamically representative to the SIM interferometer. An artificial star feeding the interferometers is installed on a separate optics bench. Voice coils are used to simulate the attitude motion of the spacecraft by moving the entire bench. Data measured on STB3 show that fringe motion of a dim star due to spacecraft attitude changes can be attenuated by 80 dB at 0.1Hz without feedback control, using only information from two guide stars. This paper describes the STB3 setup, the pathlength feed-forward architecture, implementation issues and data collected with the system.
The Centennial of GR: Looking forward to Black Hole Mergers at Cosmic Dawn

NASA Astrophysics Data System (ADS)

Cornish, Neil J.

2015-01-01

Einstein's theory of gravity has fundamentally altered mankind's conception of the Universe and its contents. Once outlandish notions such as the Universe expanding from a mere speck to its current vast size, or stars collapsing to form black holes are now well supported pillars of modern astronomy. Gravity is the dominant force that shapes the Universe, and gravity is behind all extremely energetic astrophysical phenomena. However, we are currently blind to the most powerful events in nature - bursts of pure gravitational wave energy from the collision of two black holes. A Laser Interferometer Space Antenna (LISA) will be able to record these collisions throughout the Universe, and provide unique insights into the co-evolution of galaxies and massive black holes. Motivated by the GR centennial, I'll take a look back at the rich and turbulent history of the LISA mission, and a look forward to the incredible science potential of its current incarnation as the European L3 eLISA mission.
Noise Performance of the Advanced LIGO Detectors

NASA Astrophysics Data System (ADS)

Hall, Evan; LIGO Scientific Collaboration

2016-03-01

Advanced LIGO has completed a four-month search for gravitational wave events using two 4-km laser interferometers separated by a 3000 km baseline. These instruments can sense spacetime strain to better than 10-23 /Hz 1 / 2 in their most sensitive frequency band (80 Hz to 400 Hz). The interferometers' sensitivity is limited by a variety of noise sources, including thermal fluctuations of the test masses and their suspensions, quantum and classical fluctuations of the laser light used to interrogate the test masses, residual environmental disturbances, and noises arising from the sensing and control of the interferometers' length and angular degrees of freedom. We present a budget of these noise sources as they appeared during the first observing run, and discuss ongoing improvements as we look forward to Advanced LIGO achieving full design sensitivity. LIGO was constructed by the California Institute of Technology and Massachusetts Institute of Technology with funding from the National Science Foundation and operates under cooperative agreement PHY-0757058.
Enhancing Combat Survivability of Existing Unmanned Aircraft Systems

DTIC Science & Technology

2008-12-01

EL/K-1861 ...........................................................30 Figure 15. RQ-4 Global Hawk Communications Architecture Showing Various...ELINT Electronic Intelligence ESM Electronic Support Measures EW Electronic Warfare EO Electro-Optics FLIR Forward Looking Infrared GPS Global ...system performance (speed, altitude, maneuverability, and agility) reduces susceptibility through system design. The RQ-4 Global Hawk is designed to fly
Control of Formation-Flying Multi-Element Space Interferometers with Direct Interferometer-Output Feedback

NASA Technical Reports Server (NTRS)

Lu, Hui-Ling; Cheng, H. L.; Lyon, Richard G.; Carpenter, Kenneth G.

2007-01-01

The long-baseline space interferometer concept involving formation flying of multiple spacecraft holds great promise as future space missions for high-resolution imagery. A major challenge of obtaining high-quality interferometric synthesized images from long-baseline space interferometers is to accurately control these spacecraft and their optics payloads in the specified configuration. Our research focuses on the determination of the optical errors to achieve fine control of long-baseline space interferometers without resorting to additional sensing equipment. We present a suite of estimation tools that can effectively extract from the raw interferometric image relative x/y, piston translational and tip/tilt deviations at the exit pupil aperture. The use of these error estimates in achieving control of the interferometer elements is demonstrated using simulated as well as laboratory-collected interferometric stellar images.
Control of Formation-Flying Multi-Element Space Interferometers with Direct Interferometer-Output Feedback

NASA Technical Reports Server (NTRS)

Lu, Hui-Ling; Cheng, Victor H. L.; Lyon, Richard G.; Carpenter, Kenneth G.

2007-01-01

The long-baseline space interferometer concept involving formation flying of multiple spacecrafts holds great promise as future space missions for high-resolution imagery. A major challenge of obtaining high-quality interferometric synthesized images from long-baseline space interferometers is to accurately control these spacecraft and their optics payloads in the specified configuration. Our research focuses on the determination of the optical errors to achieve fine control of long-baseline space interferometers without resorting to additional sensing equipment. We present a suite of estimation tools that can effectively extract from the raw interferometric image relative x/y, piston translational and tip/tilt deviations at the exit pupil aperture. The use of these error estimates in achieving control of the interferometer elements is demonstrated using simulated as well as laboratory-collected interferometric stellar images.
Forward scattering in two-beam laser interferometry

NASA Astrophysics Data System (ADS)

Mana, G.; Massa, E.; Sasso, C. P.

2018-04-01

A fractional error as large as 25 pm mm-1 at the zero optical-path difference has been observed in an optical interferometer measuring the displacement of an x-ray interferometer used to determine the lattice parameter of silicon. Detailed investigations have brought to light that the error was caused by light forward-scattered from the beam feeding the interferometer. This paper reports on the impact of forward-scattered light on the accuracy of two-beam optical interferometry applied to length metrology, and supplies a model capable of explaining the observed error.
Proceedings from the 2nd International Symposium on Formation Flying Missions and Technologies

NASA Technical Reports Server (NTRS)

2004-01-01

Topics discussed include: The Stellar Imager (SI) "Vision Mission"; First Formation Flying Demonstration Mission Including on Flight Nulling; Formation Flying X-ray Telescope in L2 Orbit; SPECS: The Kilometer-baseline Far-IR Interferometer in NASA's Space Science Roadmap Presentation; A Tight Formation for Along-track SAR Interferometry; Realization of the Solar Power Satellite using the Formation Flying Solar Reflector; SIMBOL-X : Formation Flying for High-Energy Astrophysics; High Precision Optical Metrology for DARWIN; Close Formation Flight of Micro-Satellites for SAR Interferometry; Station-Keeping Requirements for Astronomical Imaging with Constellations of Free-Flying Collectors; Closed-Loop Control of Formation Flying Satellites; Formation Control for the MAXIM Mission; Precision Formation Keeping at L2 Using the Autonomous Formation Flying Sensor; Robust Control of Multiple Spacecraft Formation Flying; Virtual Rigid Body (VRB) Satellite Formation Control: Stable Mode-Switching and Cross-Coupling; Electromagnetic Formation Flight (EMFF) System Design, Mission Capabilities, and Testbed Development; Navigation Algorithms for Formation Flying Missions; Use of Formation Flying Small Satellites Incorporating OISL's in a Tandem Cluster Mission; Semimajor Axis Estimation Strategies; Relative Attitude Determination of Earth Orbiting Formations Using GPS Receivers; Analysis of Formation Flying in Eccentric Orbits Using Linearized Equations of Relative Motion; Conservative Analytical Collision Probabilities for Orbital Formation Flying; Equations of Motion and Stability of Two Spacecraft in Formation at the Earth/Moon Triangular Libration Points; Formations Near the Libration Points: Design Strategies Using Natural and Non-Natural Ares; An Overview of the Formation and Attitude Control System for the Terrestrial Planet Finder Formation Flying Interferometer; GVE-Based Dynamics and Control for Formation Flying Spacecraft; GNC System Design for a New Concept of X-Ray Distributed Telescope; GNC System for the Deployment and Fine Control of the DARWIN Free-Flying Interferometer; Formation Algorithm and Simulation Testbed; and PLATFORM: A Formation Flying, RvD and Robotic Validation Test-bench.
Formation Algorithms and Simulation Testbed

NASA Technical Reports Server (NTRS)

Wette, Matthew; Sohl, Garett; Scharf, Daniel; Benowitz, Edward

2004-01-01

Formation flying for spacecraft is a rapidly developing field that will enable a new era of space science. For one of its missions, the Terrestrial Planet Finder (TPF) project has selected a formation flying interferometer design to detect earth-like planets orbiting distant stars. In order to advance technology needed for the TPF formation flying interferometer, the TPF project has been developing a distributed real-time testbed to demonstrate end-to-end operation of formation flying with TPF-like functionality and precision. This is the Formation Algorithms and Simulation Testbed (FAST) . This FAST was conceived to bring out issues in timing, data fusion, inter-spacecraft communication, inter-spacecraft sensing and system-wide formation robustness. In this paper we describe the FAST and show results from a two-spacecraft formation scenario. The two-spacecraft simulation is the first time that precision end-to-end formation flying operation has been demonstrated in a distributed real-time simulation environment.
Terrestrial Planet Finder Interferometer: Architecture, Mission Design, and Technology Development

NASA Technical Reports Server (NTRS)

Henry, Curt

2004-01-01

This slide presentation represents an overview progress report about the system design and technology development of two interferometer concepts studied for the Terrestrial Planet Finder (TPF) project. The two concepts are a structurally-connected interferometer (SCI) intended to fulfill minimum TPF science goals and a formation-flying interferometer (FFI) intended to fulfill full science goals. Described are major trades, analyses, and technology experiments completed. Near term plans are also described. This paper covers progress since August 2003
Progress and Prospects toward a Space-based Gravitational-Wave Observatory

NASA Technical Reports Server (NTRS)

Baker, John

2012-01-01

Over the last few years there has been much activity in the effort to produce a space-based gravitational-wave observatory. These efforts have enriched the understanding of the scientific capabilities of such an observatory leading to broad recognition of its value as an astronomical instrument. At the same time, rapidly developing events in the US and Europe have lead to a more complicated outlook than the baseline Laser Interferometer Space Antenna (LISA) project plan of a few years ago. I will discuss recent progress and developments resulting from the European eLISA study and the SGO study in the US and prospects looking forward.
Analytical evaluation of ILM sensors, volume 1

NASA Technical Reports Server (NTRS)

Kirk, R. J.

1975-01-01

The functional requirements and operating environment constraints are defined for an independent landing monitor ILM which provides the flight crew with an independent assessment of the operation of the primary automatic landing system. The capabilities of radars, TV, forward looking infrared radiometers, multilateration, microwave radiometers, interferometers, and nuclear sensing concepts to meet the ILM conditions are analyzed. The most critical need for the ILM appears in the landing sequence from 1000 to 2000 meters from threshold through rollout. Of the sensing concepts analyzed, the following show potential of becoming feasible ILM's: redundant microwave landings systems, precision approach radar, airborne triangulation radar, multilateration with radar altimetry, and nuclear sensing.

IMPACT OF η{sub Earth} ON THE CAPABILITIES OF AFFORDABLE SPACE MISSIONS TO DETECT BIOSIGNATURES ON EXTRASOLAR PLANETS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Léger, Alain; Defrère, Denis; Malbet, Fabien

2015-08-01

We present an analytic model to estimate the capabilities of space missions dedicated to the search for biosignatures in the atmosphere of rocky planets located in the habitable zone of nearby stars. Relations between performance and mission parameters, such as mirror diameter, distance to targets, and radius of planets, are obtained. Two types of instruments are considered: coronagraphs observing in the visible, and nulling interferometers in the thermal infrared. Missions considered are: single-pupil coronagraphs with a 2.4 m primary mirror, and formation-flying interferometers with 4 × 0.75 m collecting mirrors. The numbers of accessible planets are calculated as a functionmore » of η{sub Earth}. When Kepler gives its final estimation for η{sub Earth}, the model will permit a precise assessment of the potential of each instrument. Based on current estimations, η{sub Earth} = 10% around FGK stars and 50% around M stars, the coronagraph could study in spectroscopy only ∼1.5 relevant planets, and the interferometer ∼14.0. These numbers are obtained under the major hypothesis that the exozodiacal light around the target stars is low enough for each instrument. In both cases, a prior detection of planets is assumed and a target list established. For the long-term future, building both types of spectroscopic instruments, and using them on the same targets, will be the optimal solution because they provide complementary information. But as a first affordable space mission, the interferometer looks the more promising in terms of biosignature harvest.« less
Measurement-Based Linear Optics

NASA Astrophysics Data System (ADS)

Alexander, Rafael N.; Gabay, Natasha C.; Rohde, Peter P.; Menicucci, Nicolas C.

2017-03-01

A major challenge in optical quantum processing is implementing large, stable interferometers. We offer a novel approach: virtual, measurement-based interferometers that are programed on the fly solely by the choice of homodyne measurement angles. The effects of finite squeezing are captured as uniform amplitude damping. We compare our proposal to existing (physical) interferometers and consider its performance for BosonSampling, which could demonstrate postclassical computational power in the near future. We prove its efficiency in time and squeezing (energy) in this setting.
Terrestrial Planet Finder Interferometer: Architecture, Mission Design and Technology Development

NASA Technical Reports Server (NTRS)

Henry, Curt; Lay, Oliver; Aung, MiMi; Gunter, Steven M.; Dubovitsky, Serge; Blackwood, Gary

2004-01-01

This overview paper is a progress report about the system design and technology development of two interferometer concepts studied for the Terrestrial Planet Finder (TPF) project. The two concepts are a structurally-connected interferometer (SCI) intended to fulfill minimum TPF science goals and a formation-flying interferometer (FFI) intended to fulfill full science goals. Described are major trades, analyses, and technology experiments completed. Near term plans are also described. This paper covers progress since August 2003 and serves as an update to a paper presented at that month's SPIE conference, 'Techniques and Instrumentation for Detection of Exoplanets.
An Overview of the Formation and Attitude Control System for the Terrestrial Planet Finder Formation Flying Interferometer

NASA Technical Reports Server (NTRS)

Scharf, Daniel P.; Hadaegh, Fred Y.; Rahman, Zahidul H.; Shields, Joel F.; Singh, Gurkipal; Wette, Matthew R.

2004-01-01

The Terrestrial Planet Finder formation flying Interferometer (TPF-I) will be a five-spacecraft, precision formation operating near the second Sun-Earth Lagrange point. As part of technology development for TPF-I, a formation and attitude control system (FACS) is being developed that achieves the precision and functionality needed for the TPF-I formation and that will be demonstrated in a distributed, real-time simulation environment. In this paper we present an overview of FACS and discuss in detail its formation estimation, guidance and control architectures and algorithms. Since FACS is currently being integrated into a high-fidelity simulation environment, component simulations demonstrating algorithm performance are presented.
An Overview of the Formation and Attitude Control System for the Terrestrial Planet Finder Formation Flying Interferometer

NASA Technical Reports Server (NTRS)

Scharf, Daniel P.; Hadaegh, Fred Y.; Rahman, Zahidul H.; Shields, Joel F.; Singh, Gurkipal

2004-01-01

The Terrestrial Planet Finder formation flying Interferometer (TPF-I) will be a five-spacecraft, precision formation operating near a Sun-Earth Lagrange point. As part of technology development for TPF-I, a formation and attitude control system (FACS) is being developed that achieves the precision and functionality associated with the TPF-I formation. This FACS will be demonstrated in a distributed, real-time simulation environment. In this paper we present an overview of the FACS and discuss in detail its constituent formation estimation, guidance and control architectures and algorithms. Since the FACS is currently being integrated into a high-fidelity simulation environment, component simulations demonstrating algorithm performance are presented.
47 CFR 51.511 - Forward-looking economic cost per unit.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 3 2010-10-01 2010-10-01 false Forward-looking economic cost per unit. 51.511... (CONTINUED) INTERCONNECTION Pricing of Elements § 51.511 Forward-looking economic cost per unit. (a) The forward-looking economic cost per unit of an element equals the forward-looking economic cost of the...
47 CFR 51.511 - Forward-looking economic cost per unit.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 3 2011-10-01 2011-10-01 false Forward-looking economic cost per unit. 51.511... (CONTINUED) INTERCONNECTION Pricing of Elements § 51.511 Forward-looking economic cost per unit. (a) The forward-looking economic cost per unit of an element equals the forward-looking economic cost of the...
47 CFR 51.511 - Forward-looking economic cost per unit.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 3 2014-10-01 2014-10-01 false Forward-looking economic cost per unit. 51.511... (CONTINUED) INTERCONNECTION Pricing of Elements § 51.511 Forward-looking economic cost per unit. (a) The forward-looking economic cost per unit of an element equals the forward-looking economic cost of the...
47 CFR 51.511 - Forward-looking economic cost per unit.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 3 2012-10-01 2012-10-01 false Forward-looking economic cost per unit. 51.511... (CONTINUED) INTERCONNECTION Pricing of Elements § 51.511 Forward-looking economic cost per unit. (a) The forward-looking economic cost per unit of an element equals the forward-looking economic cost of the...
47 CFR 51.511 - Forward-looking economic cost per unit.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 3 2013-10-01 2013-10-01 false Forward-looking economic cost per unit. 51.511... (CONTINUED) INTERCONNECTION Pricing of Elements § 51.511 Forward-looking economic cost per unit. (a) The forward-looking economic cost per unit of an element equals the forward-looking economic cost of the...
The role of visual and mechanosensory cues in structuring forward flight in Drosophila melanogaster.

PubMed

Budick, Seth A; Reiser, Michael B; Dickinson, Michael H

2007-12-01

It has long been known that many flying insects use visual cues to orient with respect to the wind and to control their groundspeed in the face of varying wind conditions. Much less explored has been the role of mechanosensory cues in orienting insects relative to the ambient air. Here we show that Drosophila melanogaster, magnetically tethered so as to be able to rotate about their yaw axis, are able to detect and orient into a wind, as would be experienced during forward flight. Further, this behavior is velocity dependent and is likely subserved, at least in part, by the Johnston's organs, chordotonal organs in the antennae also involved in near-field sound detection. These wind-mediated responses may help to explain how flies are able to fly forward despite visual responses that might otherwise inhibit this behavior. Expanding visual stimuli, such as are encountered during forward flight, are the most potent aversive visual cues known for D. melanogaster flying in a tethered paradigm. Accordingly, tethered flies strongly orient towards a focus of contraction, a problematic situation for any animal attempting to fly forward. We show in this study that wind stimuli, transduced via mechanosensory means, can compensate for the aversion to visual expansion and thus may help to explain how these animals are indeed able to maintain forward flight.
The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII)

NASA Technical Reports Server (NTRS)

Rinehart, Stephen

2012-01-01

The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII) is an 8-meter baseline far-infrared interferometer to fly on a high altitude balloon. BETTII uses a double-Fourier Michelson interferometer to simultaneously obtain spatial and spectral information on science targets; the long baseline provides subarcsecond angular resolution, a capability unmatched by other far-infrared facilities. Here, we present key aspects of the overall design of the mission and provide an overview of the current status of the project. We also discuss briefly the implications of this experiment for future space-based far-infrared interferometers.
Fly Ear Inspired Miniature Acoustic Sensors for Detection and Localization

DTIC Science & Technology

2011-07-31

Micro-Opto-Electro-Mechnical-System ( MOEMS ) sensor platform that is capable of integrating multiplexed Fabry-Perot (FP) interferometer based sensors. A...on a single MOEMS chip is shown in Figure 8. Light from a low coherence light source with a coherence length Lc is first sent to the reference...towards developing a low coherence interferometer based MOEMS detection system. An optical Micro-Electro-Mechanical-System (MEMS) sensor platform was
Animal behavior: fly flight moves forward.

PubMed

Fox, Jessica L; Frye, Mark

2013-04-08

A new study has resolved the paradox of how flies maintain reflexive aversion to your approaching swatter, whilst tolerating similar visual signals during normal forward flight. Copyright © 2013 Elsevier Ltd. All rights reserved.
47 CFR 51.505 - Forward-looking economic cost.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 3 2010-10-01 2010-10-01 false Forward-looking economic cost. 51.505 Section... (CONTINUED) INTERCONNECTION Pricing of Elements § 51.505 Forward-looking economic cost. (a) In general. The forward-looking economic cost of an element equals the sum of: (1) The total element long-run incremental...
47 CFR 51.513 - Proxies for forward-looking economic cost.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 3 2010-10-01 2010-10-01 false Proxies for forward-looking economic cost. 51... SERVICES (CONTINUED) INTERCONNECTION Pricing of Elements § 51.513 Proxies for forward-looking economic cost... a cost study that complies with the forward-looking economic cost based pricing methodology...
47 CFR 51.505 - Forward-looking economic cost.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 3 2013-10-01 2013-10-01 false Forward-looking economic cost. 51.505 Section... (CONTINUED) INTERCONNECTION Pricing of Elements § 51.505 Forward-looking economic cost. (a) In general. The forward-looking economic cost of an element equals the sum of: (1) The total element long-run incremental...
47 CFR 51.505 - Forward-looking economic cost.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 3 2012-10-01 2012-10-01 false Forward-looking economic cost. 51.505 Section... (CONTINUED) INTERCONNECTION Pricing of Elements § 51.505 Forward-looking economic cost. (a) In general. The forward-looking economic cost of an element equals the sum of: (1) The total element long-run incremental...
47 CFR 51.513 - Proxies for forward-looking economic cost.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 3 2012-10-01 2012-10-01 false Proxies for forward-looking economic cost. 51... SERVICES (CONTINUED) INTERCONNECTION Pricing of Elements § 51.513 Proxies for forward-looking economic cost... a cost study that complies with the forward-looking economic cost based pricing methodology...
47 CFR 51.513 - Proxies for forward-looking economic cost.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 3 2014-10-01 2014-10-01 false Proxies for forward-looking economic cost. 51... SERVICES (CONTINUED) INTERCONNECTION Pricing of Elements § 51.513 Proxies for forward-looking economic cost... a cost study that complies with the forward-looking economic cost based pricing methodology...

47 CFR 51.505 - Forward-looking economic cost.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 3 2014-10-01 2014-10-01 false Forward-looking economic cost. 51.505 Section... (CONTINUED) INTERCONNECTION Pricing of Elements § 51.505 Forward-looking economic cost. (a) In general. The forward-looking economic cost of an element equals the sum of: (1) The total element long-run incremental...
47 CFR 51.513 - Proxies for forward-looking economic cost.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 3 2013-10-01 2013-10-01 false Proxies for forward-looking economic cost. 51... SERVICES (CONTINUED) INTERCONNECTION Pricing of Elements § 51.513 Proxies for forward-looking economic cost... a cost study that complies with the forward-looking economic cost based pricing methodology...
47 CFR 51.505 - Forward-looking economic cost.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 3 2011-10-01 2011-10-01 false Forward-looking economic cost. 51.505 Section... (CONTINUED) INTERCONNECTION Pricing of Elements § 51.505 Forward-looking economic cost. (a) In general. The forward-looking economic cost of an element equals the sum of: (1) The total element long-run incremental...
47 CFR 51.513 - Proxies for forward-looking economic cost.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 3 2011-10-01 2011-10-01 false Proxies for forward-looking economic cost. 51... SERVICES (CONTINUED) INTERCONNECTION Pricing of Elements § 51.513 Proxies for forward-looking economic cost... a cost study that complies with the forward-looking economic cost based pricing methodology...
Forward Looking Radar Imaging by Truncated Singular Value Decomposition and Its Application for Adverse Weather Aircraft Landing.

PubMed

Huang, Yulin; Zha, Yuebo; Wang, Yue; Yang, Jianyu

2015-06-18

The forward looking radar imaging task is a practical and challenging problem for adverse weather aircraft landing industry. Deconvolution method can realize the forward looking imaging but it often leads to the noise amplification in the radar image. In this paper, a forward looking radar imaging based on deconvolution method is presented for adverse weather aircraft landing. We first present the theoretical background of forward looking radar imaging task and its application for aircraft landing. Then, we convert the forward looking radar imaging task into a corresponding deconvolution problem, which is solved in the framework of algebraic theory using truncated singular decomposition method. The key issue regarding the selecting of the truncated parameter is addressed using generalized cross validation approach. Simulation and experimental results demonstrate that the proposed method is effective in achieving angular resolution enhancement with suppressing the noise amplification in forward looking radar imaging.
47 CFR 54.309 - Calculation and distribution of forward-looking support for non-rural carriers.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 3 2011-10-01 2011-10-01 false Calculation and distribution of forward-looking... Areas § 54.309 Calculation and distribution of forward-looking support for non-rural carriers. (a... incumbent local exchange carriers, shall receive universal service support for the forward-looking economic...
Balloon Exoplanet Nulling Interferometer (BENI)

NASA Technical Reports Server (NTRS)

Lyon, Richard G.; Clampin, Mark; Woodruff, Robert A.; Vasudevan, Gopal; Ford, Holland; Petro, Larry; Herman, Jay; Rinehart, Stephen; Carpenter, Kenneth; Marzouk, Joe

2009-01-01

We evaluate the feasibility of using a balloon-borne nulling interferometer to detect and characterize exosolar planets and debris disks. The existing instrument consists of a 3-telescope Fizeau imaging interferometer with 3 fast steering mirrors and 3 delay lines operating at 800 Hz for closed-loop control of wavefront errors and fine pointing. A compact visible nulling interferometer is under development which when coupled to the imaging interferometer would in-principle allow deep suppression of starlight. We have conducted atmospheric simulations of the environment above 100,000 feet and believe balloons are a feasible path forward towards detection and characterization of a limited set of exoplanets and their debris disks. Herein we will discuss the BENI instrument, the balloon environment and the feasibility of such as mission.
A heterodyne interferometer for high resolution translation and tilt measurement as optical readout for the LISA inertial sensor

NASA Astrophysics Data System (ADS)

Schuldt, Thilo; Kraus, Hans-Jürgen; Weise, Dennis; Braxmaier, Claus; Peters, Achim; Johann, Ulrich

2017-11-01

The space-based gravitational wave detector LISA (Laser Interferometer Space Antenna) requires a high performance position sensor in order to measure the translation and tilt of the free flying test mass with respect to the LISA optical bench. Here, we present a mechanically highly stable and compact setup of a heterodyne interferometer combined with differential wavefront sensing for the tilt measurement which serves as a demonstrator for an optical readout of the LISA test mass position. First results show noise levels below 1 nm/√Hz and 1 μrad/√Hz, respectively, for frequencies < 10-3 Hz.
Design and Status of the Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII): An Interferometer at the Edge of Space

NASA Technical Reports Server (NTRS)

Rinehart, Stephen A.; Barclay, Richard B.; Barry, R. K.; Benford, D. J.; Calhoun, P. C.; Fixsen, D. J.; Gorman, E. T.; Jackson, M. L.; Jhabvala, C. A.; Leisawitz, D. T.;

2012-01-01

The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII) is an 8-meter baseline far-infraredinterferometer designed to fly on a high altitude balloon. BETTII uses a double-Fourier Michelson interferometer tosimultaneously obtain spatial and spectral information on science targets; the long baseline permits subarcsecond angular resolution, a capability unmatched by other far-infrared facilities. Here, we present key aspects of the overall design of the mission and provide an overview of the current status of the project. We also discuss briefly the implications of this experiment for future space-based far-infrared interferometers.

Investigation of Space Interferometer Control Using Imaging Sensor Output Feedback

NASA Technical Reports Server (NTRS)

Leitner, Jesse A.; Cheng, Victor H. L.

2003-01-01

Numerous space interferometry missions are planned for the next decade to verify different enabling technologies towards very-long-baseline interferometry to achieve high-resolution imaging and high-precision measurements. These objectives will require coordinated formations of spacecraft separately carrying optical elements comprising the interferometer. High-precision sensing and control of the spacecraft and the interferometer-component payloads are necessary to deliver sub-wavelength accuracy to achieve the scientific objectives. For these missions, the primary scientific product of interferometer measurements may be the only source of data available at the precision required to maintain the spacecraft and interferometer-component formation. A concept is studied for detecting the interferometer's optical configuration errors based on information extracted from the interferometer sensor output. It enables precision control of the optical components, and, in cases of space interferometers requiring formation flight of spacecraft that comprise the elements of a distributed instrument, it enables the control of the formation-flying vehicles because independent navigation or ranging sensors cannot deliver the high-precision metrology over the entire required geometry. Since the concept can act on the quality of the interferometer output directly, it can detect errors outside the capability of traditional metrology instruments, and provide the means needed to augment the traditional instrumentation to enable enhanced performance. Specific analyses performed in this study include the application of signal-processing and image-processing techniques to solve the problems of interferometer aperture baseline control, interferometer pointing, and orientation of multiple interferometer aperture pairs.
Astronomy from Space: The Hubble, Herschel and James Webb Space Telescopes

NASA Technical Reports Server (NTRS)

Gardner, Jonathan P.

2009-01-01

Space-based astronomy is going through a renaissance, with three Great Observatories currently flying: Hubble in the visible and ultraviolet, Spitzer in the infrared and Chandra in X-rays. The future looks equally bright. The final servicing mission to Hubble will take place in February 2009 and promises to make the observatory more capable than ever with two new cameras, and refurbishment that will allow it to last at least five years. The upcoming launch of the Herschel Space Telescope will open the far-infrared to explore the cool and dusty Universe. Finally, we look forward to the launch of the James Webb Space Telescope in 2013, which wil provide a successor to both Hubble and Spitzer. In this talk, the author discusses some of the highlights of scientific discovery in the last 10 years and reveals the promise to the next 10 years.
CubeSat Packaged Electrospray Thruster Evaluation for Enhanced Operationally Responsive Space Capabilities

DTIC Science & Technology

2011-03-24

These satellites can perform many missions including: close formation flying with other CubeSats, and possible docking with a large satellite to...in 2008 to fly on the NASA LISA mission. LISA, the Laser Interferometer Space Antenna, is a joint NASA–ESA mission to observe astrophysical and...for mass spectrometry of large organic molecules popularized the technology and made components such as needles or other components readily
Demonstration of a robust magnonic spin wave interferometer.

PubMed

Kanazawa, Naoki; Goto, Taichi; Sekiguchi, Koji; Granovsky, Alexander B; Ross, Caroline A; Takagi, Hiroyuki; Nakamura, Yuichi; Inoue, Mitsuteru

2016-07-22

Magnonics is an emerging field dealing with ultralow power consumption logic circuits, in which the flow of spin waves, rather than electric charges, transmits and processes information. Waves, including spin waves, excel at encoding information via their phase using interference. This enables a number of inputs to be processed in one device, which offers the promise of multi-input multi-output logic gates. To realize such an integrated device, it is essential to demonstrate spin wave interferometers using spatially isotropic spin waves with high operational stability. However, spin wave reflection at the waveguide edge has previously limited the stability of interfering waves, precluding the use of isotropic spin waves, i.e., forward volume waves. Here, a spin wave absorber is demonstrated comprising a yttrium iron garnet waveguide partially covered by gold. This device is shown experimentally to be a robust spin wave interferometer using the forward volume mode, with a large ON/OFF isolation value of 13.7 dB even in magnetic fields over 30 Oe.
Demonstration of a robust magnonic spin wave interferometer

PubMed Central

Kanazawa, Naoki; Goto, Taichi; Sekiguchi, Koji; Granovsky, Alexander B.; Ross, Caroline A.; Takagi, Hiroyuki; Nakamura, Yuichi; Inoue, Mitsuteru

2016-01-01

Magnonics is an emerging field dealing with ultralow power consumption logic circuits, in which the flow of spin waves, rather than electric charges, transmits and processes information. Waves, including spin waves, excel at encoding information via their phase using interference. This enables a number of inputs to be processed in one device, which offers the promise of multi-input multi-output logic gates. To realize such an integrated device, it is essential to demonstrate spin wave interferometers using spatially isotropic spin waves with high operational stability. However, spin wave reflection at the waveguide edge has previously limited the stability of interfering waves, precluding the use of isotropic spin waves, i.e., forward volume waves. Here, a spin wave absorber is demonstrated comprising a yttrium iron garnet waveguide partially covered by gold. This device is shown experimentally to be a robust spin wave interferometer using the forward volume mode, with a large ON/OFF isolation value of 13.7 dB even in magnetic fields over 30 Oe. PMID:27443989
Averaging of phase noise in PSK signals by an opto-electrical feed-forward circuit

NASA Astrophysics Data System (ADS)

Inoue, K.; Ohta, M.

2013-10-01

This paper proposes an opto-electrical feed-forward circuit that reduces phase noise in binary PSK signals by averaging the noise. Random and independent phase noise is averaged over several bit slots by externally modulating a phase-fluctuating PSK signal with feed-forward signal obtained from signal processing of the outputs of delay interferometers. The simulation results demonstrate a reduction in the phase noise.
Progress in four-beam nulling: results from the Terrestrial Planet Finder planet detection testbed

NASA Technical Reports Server (NTRS)

Martin, Stefan

2006-01-01

The Terrestrial Planet Finder Interferometer (TPF-I) is a large space telescope consisting of four 4 meter diameter telescopes flying in formation in space together with a fifth beam combiner spacecraft.
Progress in four-beam nulling: results from the Terrestrial Planet Finder Planet Detection Testbed

NASA Technical Reports Server (NTRS)

Martin, Stefan

2006-01-01

The Terrestrial Planet Finder Interferometer (TPF-I) is a large space telescope consisting of four 4 meter diameter telescopes flying in formation in space together with a fifth beam combiner spacecraft.
Alignment and Polarization Sensitivity Study for the Cassini-Composite InfraRed Spectrometer (CIRS) Far InfraRed (FIR) Interferometer

NASA Technical Reports Server (NTRS)

Crooke, Julie A.; Hagopian, John G.

1998-01-01

The Composite InfraRed Spectrometer (CIRS) instrument flying on the Cassini spacecraft to Saturn is a cryogenic spectrometer with far-infrared (FIR) and mid-infrared (MIR) channels. The CIRS FIR channel is a polarizing interferometer that contains three polarizing grid components. These components are an input polarizer, a polarizing beamsplitter, and an output polarizer/analyzer. They consist of a 1.5 micron thick mylar substrate with 2 gm wide copper wires, with 2 gm spacing (4 micron pitch) photolithographically deposited on the substrate. This paper details the polarization sensitivity studies performed on the output polarizer/analyzer, and the alignment sensitivity studies performed on the input polarizer and beamsplitter components in the FIR interferometer.
Ramifications of the recent FAA rule for windshear systems on the development of forward-looking systems

NASA Technical Reports Server (NTRS)

Adamson, H. Patrick

1990-01-01

The recent Federal Aviation Administration (FAA) rule requiring windshear systems with flight guidance may have severe ramifications for the development of infrared and other forward-looking systems. The industry needs to have and can have a more cost effective option through the use of a forward-looking system with a reactive backup instead of a reactive system with flight guidance. However, because of the short time for compliance with the new FAA rule, it is possible that existing transport aircraft will be in full compliance before a comprehensive investigation of all forward-looking systems can be completed. If this occurs, it is possible that the market for forward-looking systems will be severely reduced, thereby eliminating the economic incentive to develop these much needed systems. Thus, to assure that this option is available for the airlines, it beehoves the industry to immediately support an in-service evaluation of all available forward-looking systems.
Relative Sensor with 4(pi) Coverage for Formation Flying Missions

NASA Technical Reports Server (NTRS)

Tien, Jeffrey Y.; Purcell, George H., Jr.; Sirinivasan, Jeffrey M.; Young, Lawrence E.

2004-01-01

The Terrestrial Planet Finder (TPF) pre-project, an element of NASA's Origins program, is currently developing two architectures for a mission to search for earth-like planets around nearby stars. One of the architectures being developed is the Formation Flying Interferometer (FFI). The FFI is envisioned to consist of up to seven spacecraft (as many as six 'collectors' with IR telescopes, and a 'combiner') flying in precise formation within f 1 cm of pre-determined trajectories for synchronized observations. The spacecraft-to-spacecraft separations are variable between 20 m and 100 m or more during observations to support various configurations of the interferometer in the planet-finding mode. The challenges involved with TPF autonomous operations, ranging from formation acquisition and formation maneuvering to high precision formation control during science observations, are unprecedented. In this paper we discuss the development of the formation acquisition sensor, which uses novel modulation and duplexing schemes to enable fast signal acquisition, multiple-spacecraft operation, and mitigation of inherent jamming conditions, while providing precise formation sensing and integrated radar capability. This approach performs delay synthesis and carrier cycle ambiguity resolution to improve range measurement, and uses differential carrier cycle ambiguity resolution to make precise bearing angle measurements without calibration maneuvers.

Relative Sensor with 4Pi Coverage for Formation Flying Missions

NASA Technical Reports Server (NTRS)

Tien, Jeffrey Y.; Purcell, George H., Jr.; Srinivasan, Jeffrey M.; Young, Lawrence E.

2004-01-01

The Terrestrial Planet Finder (TPF) pre-project, an element of NASA s Origins program, is currently developing two architectures for a mission to search for earth-like planets around nearby stars. One of the architectures being developed is the Formation Flying Interferometer (FFI). The FFI is envisioned to consist of up to seven spacecraft (as many as six "collectors" with IR telescopes, and a "combiner") flying in precise formation within +/-1 cm of pre-determined trajectories for synchronized observations. The spacecraft-to-spacecraft separations are variable between 20 m and 100 m or more during observations to support various configurations of the interferometer in the planet-finding mode. The challenges involved with TPF autonomous operations, ranging from formation acquisition and formation maneuvering to high precision formation control during science observations, are unprecedented. In this paper we discuss the development of the formation acquisition sensor, which uses novel modulation and duplexing schemes to enable fast signal acquisition, multiple-spacecraft operation, and mitigation of inherent jamming conditions, while providing precise formation sensing and integrated radar capability. This approach performs delay synthesis and carrier cycle ambiguity resolution to improve range measurement, and uses differential carrier cycle ambiguity resolution to make precise bearing angle measurements without calibration maneuvers.
47 CFR 54.309 - Calculation and distribution of forward-looking support for non-rural carriers.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 3 2010-10-01 2010-10-01 false Calculation and distribution of forward-looking... Areas § 54.309 Calculation and distribution of forward-looking support for non-rural carriers. (a...) Distribution of total support available per state. The total amount of support available per State calculated...
65. FORWARD EMERGENCY DIESEL GENERATOR SET AFT LOOKING FORWARD ...

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

65. FORWARD EMERGENCY DIESEL GENERATOR SET - AFT LOOKING FORWARD SHOWING TOP HALF OF FAIRBANKS MORSE 36D81/8 TEN CYLINDER DIESEL ENGINE SERIAL #951230 AND EXHAUST SYSTEM. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
Temperature Effects on Olive Fruit Fly Infestation in the FlySim Cellular Automata Model

NASA Astrophysics Data System (ADS)

Bruno, Vincenzo; Baldacchini, Valerio; di Gregorio, Salvatore

FlySim is a Cellular Automata model developed for simulating infestation of olive fruit flies (Bactrocera Oleae) on olive (Olea europaea) groves. The flies move into the groves looking for mature olives where eggs are spawn. This serious agricultural problem is mainly tackled by using chemical agents at the first signs of the infestation, but organic productions with no or few chemicals are strongly requested by the market. Oil made with infested olives is poor in quality, nor olives are suitable for selling in stores. The FlySim model simulates the diffusion of flies looking for mature olives and the growing of flies due to atmospheric conditions. Foreseeing an infestation is the best way to prevent it and to reduce the need of chemicals in agriculture. In this work we investigated the effects of temperature on olive fruit flies and resulting infestation during late spring and summer.
17 CFR 230.168 - Exemption from sections 2(a)(10) and 5(c) of the Act for certain communications of regularly...

Code of Federal Regulations, 2011 CFR

2011-04-01

... and forward-looking information. 230.168 Section 230.168 Commodity and Securities Exchanges SECURITIES... factual business information and forward-looking information. Preliminary Notes to § 230.168. 1. This... provides a non-exclusive safe harbor for factual business information and forward-looking information...
The Amateur Scientist.

ERIC Educational Resources Information Center

Walker, Jearl

1984-01-01

Discusses the optics of fly fishing, considering where to cast the fly once a fish is seen. Also considers what the fisherman looks like to the fish, examining refraction at a water surface, actual and apparent light rays, and how sticks in the water might look to a fish. (JN)
Blood feeding behavior of the stable fly

USDA-ARS?s Scientific Manuscript database

Stable fly is a fly that looks similar to a house fly but both sexes are blood feeders. Blood is required for successful fertilization and development of eggs. Bites are painful but there is usually no pain after the fly stops feeding. The stable fly is a persistent feeder and will continue trying t...
TPF-I Emma X-Array: 2007 Design Team Study

NASA Technical Reports Server (NTRS)

Martin, Stefan R.; Rodriguez, Jose; Scharf, Dan; Smith, Jim; McKinstry, David; Wirz, Richie; Purcell, George; Wayne, Len; Scherr, Larry; Mennesson, Bertrand;

2007-01-01

This viewgraph presentation is a study of an Emma design for Terrestrial Planet Finder (TPF) formation flying interferometer. The objective is to develop a design with reduced cost compared to TPF-I X-Array, derive mass and cost estimates, and study thermal and radiation issues.

Recent Developments on Airborne Forward Looking Interferometer for the Detection of Wake Vortices

NASA Technical Reports Server (NTRS)

Daniels, Taumi S.; Smith, William L.; Kirev, Stanislav

2012-01-01

A goal of these studies was development of the measurement methods and algorithms necessary to detect wake vortex hazards in real time from either an aircraft or ground-based hyperspectral Fourier Transform Spectrometer (FTS). This paper provides an update on research to model FTS detection of wake vortices. The Terminal Area Simulation System (TASS) was used to generate wake vortex fields of 3-D winds, temperature, and absolute humidity. These fields were input to the Line by Line Radiative Transfer Model (LBLRTM), a hyperspectral radiance model in the infrared, employed for the FTS numerical modeling. An initial set of cases has been analyzed to identify a wake vortex IR signature and signature sensitivities to various state variables. Results from the numerical modeling case studies will be presented. Preliminary results indicated that an imaging IR instrument sensitive to six narrow bands within the 670 to 3150 per centimeter spectral region would be sufficient for wake vortex detection. Noise floor estimates for a recommended instrument are a current research topic.
The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII)

NASA Technical Reports Server (NTRS)

Rinehart, Stephen A.

2010-01-01

Astronomical studies at infrared wavelengths have dramatically improved our understanding of the universe. The relatively low angular resolution of these missions, however, is insufficient to resolve the physical scale on which mid-to far-infrared emission arises. We will build the Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII), an eight-meter Michelson interferometer to fly on a high-altitude balloon. BETTII's spectral-spatial capability, provided by an instrument using double-Fourier techniques, will address key questions about the nature of disks in young star clusters and active galactic nuclei and the envelopes of evolved stars. BETTII will also lay the technological groundwork for future space interferometers.
BETTII: The Balloon Experimental Twin Telescope for Infrared Interferometry

NASA Technical Reports Server (NTRS)

Rinehart, Stephen

2011-01-01

Astronomical studies at infrared wavelengths have dramatically improved our understanding the universe. The relatively low angular resolution of these missions, however, is insufficient to resolve the physical scale on which mid-to far-infrared emission arises. We will build the Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII),8oeight-meter Michelson interferometer to fly on a high-altitude balloon. BETTII's spectral-spatial capability, provided by an instrument using double-Fourier techniques, will address key questions about the nature of disks io young star clusters and active galactic nuclei and the envelopes of evolved stars. BETTII will also lay the technological groundwork for future space interferometers.
6. Detail of forward fuselage showing open cockpit hatch and ...

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

6. Detail of forward fuselage showing open cockpit hatch and ladder. View to southeast. - Offutt Air Force Base, Looking Glass Airborne Command Post, Looking Glass Aircraft, On Operational Apron covering northeast half of Project Looking Glass Historic District, Bellevue, Sarpy County, NE
Feiring's concept of forward-looking responsibility: a dead end for responsibility in healthcare.

PubMed

Albertsen, Andreas

2015-02-01

Eli Feiring has developed a concept of forward-looking responsibility in healthcare. On this account, what matters morally in the allocation of scarce healthcare resources is not people's past behaviours but rather their commitment to take on lifestyles that will increase the benefit acquired from received treatment. According to Feiring, this is to be preferred over the backward-looking concept of responsibility often associated with luck egalitarianism. The article critically scrutinises Feiring's position. It begins by spelling out the wider implications of Feiring's view. Against this background, it shows that (i) Feiring's distinction between backward-looking and forward-looking responsibility is incompatible with the Scanlonian notion of responsibility she apparently endorses; (ii) her favoured forward-looking notion of responsibility is subject to the objections levelled against the luck egalitarian view (whatever the strength of such objections). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Response of a PCF-based modal interferometer to lateral stress: Resonant behavior and performance as sensor

NASA Astrophysics Data System (ADS)

Sanz-Felipe, Á.; Martín, J. C.

2017-11-01

The performance of a fiber-based modal interferometer as lateral stress sensor has been analyzed, both for static and periodic forces applied on it. The central fiber of the interferometer is a photonic crystal fiber. Forces are applied on it perpendicular to its axis, so that they squeeze it. In static situations, changes in the transmission spectrum of the interferometer are studied as a function of the charges applied. Measurements with several interferometers have been carried out in order to analyze the influence of its length and of its splices' transmission on the device operation, looking for optimization of its linearity and sensibility. The effect of periodic charges, as an emulation of vibrations, has also been studied. The analysis is centered on the frequency dependence of the response. In linear regime (small enough periodic charges), the results obtained are satisfactorily explained by treating the central fiber of the interferometer as a mechanical resonator whose vibration modes coincide with the ones of a cylinder with clamped ends. In nonlinear regime, period doubling and other anharmonic behaviors have been observed.
A first look at salience and distinctiveness of fly-over and fly-by waypoint symbology

DOT National Transportation Integrated Search

2000-09-01

This report presents the findings of a short-term empirical study on human factors issues related to the : selection of symbology for fly-over and fly-by waypoints on aeronautical charts. At issue were the : international standards for the depiction ...
Sun Radio Interferometer Space Experiment (SunRISE)

NASA Astrophysics Data System (ADS)

Kasper, Justin C.; SunRISE Team

2018-06-01

The Sun Radio Interferometer Space Experiment (SunRISE) is a NASA Heliophysics Explorer Mission of Opportunity currently in Phase A. SunRISE is a constellation of spacecraft flying in a 10-km diameter formation and operating as the first imaging radio interferometer in space. The purpose of SunRISE is to reveal critical aspects of solar energetic particle (SEP) acceleration at coronal mass ejections (CMEs) and transport into space by making the first spatially resolved observations of coherent Type II and III radio bursts produced by electrons accelerated at CMEs or released from flares. SunRISE will focus on solar Decametric-Hectometric (DH, 0.1 < f < 15 MHz) radio bursts that always are detected from space before major SEP events, but cannot be seen on Earth due to ionospheric absorption. This talk will describe SunRISE objectives and implementation. Presented on behalf of the entire SunRISE team.
Interferometry on a Balloon; Paving the Way for Space-based Interferometers

NASA Technical Reports Server (NTRS)

Rinehart, Stephen A.

2008-01-01

Astronomical studies at infrared wavelengths have dramatically improved our understanding of the universe, and observations with Spitzer, the upcoming Herschel mission, and SOFIA will continue to provide exciting new discoveries. The relatively low angular resolution of these missions, however, is insufficient to resolve the physical scale on which mid-to-far-infrared emission arises, resulting in source and structure ambiguities that limit our ability to answer key science questions. Interferometry enables high angular resolution at these wavelengths- a powerful tool for scientific discovery. We will build the Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII), an eight-meter baseline Michelson stellar interferometer to fly on a high-altitude balloon. BETTII's spectral-spatial capability, provided by an instrument using double-Fourier techniques, will address key questions about the nature of disks in young star clusters and active galactic nuclei and the envelopes of evolved stars. BETTII will also lay the technological groundwork for future space interferometers.
1D-VAR Retrieval Using Superchannels

NASA Technical Reports Server (NTRS)

Liu, Xu; Zhou, Daniel; Larar, Allen; Smith, William L.; Schluessel, Peter; Mango, Stephen; SaintGermain, Karen

2008-01-01

Since modern ultra-spectral remote sensors have thousands of channels, it is difficult to include all of them in a 1D-var retrieval system. We will describe a physical inversion algorithm, which includes all available channels for the atmospheric temperature, moisture, cloud, and surface parameter retrievals. Both the forward model and the inversion algorithm compress the channel radiances into super channels. These super channels are obtained by projecting the radiance spectra onto a set of pre-calculated eigenvectors. The forward model provides both super channel properties and jacobian in EOF space directly. For ultra-spectral sensors such as Infrared Atmospheric Sounding Interferometer (IASI) and the NPOESS Airborne Sounder Testbed Interferometer (NAST), a compression ratio of more than 80 can be achieved, leading to a significant reduction in computations involved in an inversion process. Results will be shown applying the algorithm to real IASI and NAST data.
Far-forward collective scattering measurements by FIR polarimeter-interferometer on J-TEXT tokamak

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shi, P.; Chen, J., E-mail: jiech@hust.edu.cn; Gao, L.

The multi-channel three-wave polarimeter-interferometer system on J-TEXT tokamak has been exploited to measure far-forward collective scattering from electron density fluctuations. The diagnostic utilizes far infrared lasers operated at 432 μm with 17-channel vertical chords (3 cm chord spacing), covering the entire cross section of plasma. Scattering laser power is measured using a high-sensitivity Schottky planar diode mixer which can also detect polarimetric and interferometric phase simultaneously. The system provides a line-integrated measurement of density fluctuations with maximum measurable wave number: k{sub ⊥max} ≤ 2 cm{sup −1} and time response up to 350 kHz. Feasibility of the diagnostic has been tested,more » showing higher sensitivity to detect fluctuation than interferometric measurement. Capability of providing spatial-resolved information of fluctuation has also been demonstrated in preliminary experimental applications.« less
Full-wave Characterization of Rough Terrain Surface Effects for Forward-looking Radar Applications: A Scattering and Imaging Study from the Electromagnetic Perspective

DTIC Science & Technology

2011-09-01

and Imaging Framework First, the parallelized 3-D FDTD algorithm is applied to simulate composite scattering from targets in a rough ground...solver as pertinent to forward-looking radar sensing , the effects of surface clutter on multistatic target imaging are illustrated with large-scale...Full-wave Characterization of Rough Terrain Surface Effects for Forward-looking Radar Applications: A Scattering and Imaging Study from the

Real-time Enhanced Vision System

NASA Technical Reports Server (NTRS)

Hines, Glenn D.; Rahman, Zia-Ur; Jobson, Daniel J.; Woodell, Glenn A.; Harrah, Steven D.

2005-01-01

Flying in poor visibility conditions, such as rain, snow, fog or haze, is inherently dangerous. However these conditions can occur at nearly any location, so inevitably pilots must successfully navigate through them. At NASA Langley Research Center (LaRC), under support of the Aviation Safety and Security Program Office and the Systems Engineering Directorate, we are developing an Enhanced Vision System (EVS) that combines image enhancement and synthetic vision elements to assist pilots flying through adverse weather conditions. This system uses a combination of forward-looking infrared and visible sensors for data acquisition. A core function of the system is to enhance and fuse the sensor data in order to increase the information content and quality of the captured imagery. These operations must be performed in real-time for the pilot to use while flying. For image enhancement, we are using the LaRC patented Retinex algorithm since it performs exceptionally well for improving low-contrast range imagery typically seen during poor visibility conditions. In general, real-time operation of the Retinex requires specialized hardware. To date, we have successfully implemented a single-sensor real-time version of the Retinex on several different Digital Signal Processor (DSP) platforms. In this paper we give an overview of the EVS and its performance requirements for real-time enhancement and fusion and we discuss our current real-time Retinex implementations on DSPs.
Real-time enhanced vision system

NASA Astrophysics Data System (ADS)

Hines, Glenn D.; Rahman, Zia-ur; Jobson, Daniel J.; Woodell, Glenn A.; Harrah, Steven D.

2005-05-01

Flying in poor visibility conditions, such as rain, snow, fog or haze, is inherently dangerous. However these conditions can occur at nearly any location, so inevitably pilots must successfully navigate through them. At NASA Langley Research Center (LaRC), under support of the Aviation Safety and Security Program Office and the Systems Engineering Directorate, we are developing an Enhanced Vision System (EVS) that combines image enhancement and synthetic vision elements to assist pilots flying through adverse weather conditions. This system uses a combination of forward-looking infrared and visible sensors for data acquisition. A core function of the system is to enhance and fuse the sensor data in order to increase the information content and quality of the captured imagery. These operations must be performed in real-time for the pilot to use while flying. For image enhancement, we are using the LaRC patented Retinex algorithm since it performs exceptionally well for improving low-contrast range imagery typically seen during poor visibility poor visibility conditions. In general, real-time operation of the Retinex requires specialized hardware. To date, we have successfully implemented a single-sensor real-time version of the Retinex on several different Digital Signal Processor (DSP) platforms. In this paper we give an overview of the EVS and its performance requirements for real-time enhancement and fusion and we discuss our current real-time Retinex implementations on DSPs.
SPECS: The Kilometer-baseline Far-IR Interferometer in NASA's Space Science Roadmap Presentation

NASA Technical Reports Server (NTRS)

Abel, Tom; Allen, Ron; Benford, Dominic; Blain, Andrew; Bombardelli, Claudio; Calzetti, Daniela; DiPirro, Michael J.; Ehrenfreund, Pascale; Evans, Neal; Fischer, Jackie

2004-01-01

A viewgraph presentation describing the Submillimeter Probe of the Evolution of Cosmic Structure (SPECS) mission is shown. The topics include: 1) Context: community planning and study status; 2) Science goals; 3) Mission requirements; 4) Mission concepts for SPIRIT and SPECS; and 5) Tethered formation flying, a key enabling technology.
The Accountability Era in US Teacher Education: Looking Back, Looking Forward

ERIC Educational Resources Information Center

Cochran-Smith, Marilyn; Baker, Megina; Burton, Stephani; Chang, Wen-Chia; Cummings Carney, Molly; Fernández, M. Beatriz; Stringer Keefe, Elizabeth; Miller, Andrew F.; Sánchez, Juan Gabriel

2017-01-01

In keeping with the theme of the 40th anniversary issue of "EJTE," this article looks back and forward at US teacher education accountability. It argues that "holding teacher education accountable" has been the major approach to reforming teacher education in the US for the last two decades, assuming that enhanced teacher…
19. DECK VIEW LOOKING FORWARD WITH MAST, RIGGING AND BOWSPRIT ...

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

19. DECK VIEW LOOKING FORWARD WITH MAST, RIGGING AND BOWSPRIT DETAILS - HATCH COVER REMOVED TO SHOW CENTERBOARD TRUNK - KATHRYN-Two-sail Bateau "Skipjack", Dogwood Harbor, Chesapeake Bay, Tilghman, Talbot County, MD
Looking Back, Looking Forward: Understanding the Impact of Using an Assistive Technology Device (ATD)--Participatory Visual Methods

ERIC Educational Resources Information Center

Bartlett, Sue; Lorenz, Laura; Rankin, Theresa; Elias, Eileen; Mustafa, Ruman; Weider, Katie

2011-01-01

This article is the eighth of a multi-part series on traumatic brain injury (TBI). This is a continuation from part A of "Looking Back, Looking Forward," published in Exceptional Parent's February issue. Managing the cost of rehabilitation for a child, teenager or young adult who has incurred a TBI can be supported through the use of an Assistive…
Strategies for the stabilization of longitudinal forward flapping flight revealed using a dynamically-scaled robotic fly.

PubMed

Elzinga, Michael J; van Breugel, Floris; Dickinson, Michael H

2014-06-01

The ability to regulate forward speed is an essential requirement for flying animals. Here, we use a dynamically-scaled robot to study how flapping insects adjust their wing kinematics to regulate and stabilize forward flight. The results suggest that the steady-state lift and thrust requirements at different speeds may be accomplished with quite subtle changes in hovering kinematics, and that these adjustments act primarily by altering the pitch moment. This finding is consistent with prior hypotheses regarding the relationship between body pitch and flight speed in fruit flies. Adjusting the mean stroke position of the wings is a likely mechanism for trimming the pitch moment at all speeds, whereas changes in the mean angle of attack may be required at higher speeds. To ensure stability, the flapping system requires additional pitch damping that increases in magnitude with flight speed. A compensatory reflex driven by fast feedback of pitch rate from the halteres could provide such damping, and would automatically exhibit gain scheduling with flight speed if pitch torque was regulated via changes in stroke deviation. Such a control scheme would provide an elegant solution for stabilization across a wide range of forward flight speeds.
Near-Earth Object Astrometric Interferometry

NASA Technical Reports Server (NTRS)

Werner, Martin R.

2005-01-01

Using astrometric interferometry on near-Earth objects (NEOs) poses many interesting and difficult challenges. Poor reflectance properties and potentially no significant active emissions lead to NEOs having intrinsically low visual magnitudes. Using worst case estimates for signal reflection properties leads to NEOs having visual magnitudes of 27 and higher. Today the most sensitive interferometers in operation have limiting magnitudes of 20 or less. The main reason for this limit is due to the atmosphere, where turbulence affects the light coming from the target, limiting the sensitivity of the interferometer. In this analysis, the interferometer designs assume no atmosphere, meaning they would be placed at a location somewhere in space. Interferometer configurations and operational uncertainties are looked at in order to parameterize the requirements necessary to achieve measurements of low visual magnitude NEOs. This analysis provides a preliminary estimate of what will be required in order to take high resolution measurements of these objects using interferometry techniques.
18. VIEW LOOKING FORWARD FROM ENGINE ROOM INTO GALLEY. STARBOARD ...

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

18. VIEW LOOKING FORWARD FROM ENGINE ROOM INTO GALLEY. STARBOARD ENGINE, FUEL TANK AND BATTERIES SHOWN IN RIGHT SIDE OF IMAGE. OIL-FIRED GALLEY STOVE AND FORWARD COMPANIONWAY LADDER IS IN VIEW THROUGH DOORWAY BEYOND. (HAER FIELD TEAM MEMBER CHRISTOPHER CYZEWSKI IN GALLEY) - Pilot Schooner "Alabama", Moored in harbor at Vineyard Haven, Vineyard Haven, Dukes County, MA
44. #3 ARRESTING GEAR ENGINE AFT LOOKING FORWARD SHOWING ...

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

44. #3 ARRESTING GEAR ENGINE - AFT LOOKING FORWARD SHOWING MURAL OF LUCY AND CHARLIE BROWN ON HYDRAULIC OIL ACCUMULATOR. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
Objective tests for forward looking pedestrian crash avoidance/mitigation systems.

DOT National Transportation Integrated Search

2014-06-01

This report documents the work completed by the Crash Avoidance Metrics Partnership (CAMP) Crash Imminent Braking : (CIB) Consortium during the project titled Objective Tests for Forward Looking Pedestrian Crash Avoidance/Mitigation : Systems. ...
Eddie Patterson enjoyed "flying" a C-17 simulator during Take Your Children to Work Day June 22 while Dryden engineer Ken Norlin and other students look on

NASA Image and Video Library

2004-06-22

Eddie Patterson, a fourth-grade student at Tehachapi's Tompkins Elementary School, enjoyed "flying" a C-17 multi-engine aircraft simulator during Take Your Children to Work Day June 22 at NASA Dryden Flight Research Center while NASA Dryden engineer Ken Norlin and other students look on.
Studies of the Lateral-Directional Flying Qualities of a Tandem Helicopter in Forward Flight

NASA Technical Reports Server (NTRS)

Amer, Kenneth B; Tapscott, Robert J

1954-01-01

An investigation of the lateral-directional flying qualities of a tandem-rotor helicopter in forward flight was undertaken to determine desirable goals for helicopter lateral-directional flying qualities and possible methods of achieving these goals in the tandem-rotor helicopter. Comparison between directional stability as measured in flight and rotor-off model tests in a wind tunnel shows qualitative agreement and, hence, indicates such wind-tunnel test, despite the absence of the rotors, to be one effective method of studying means of improving the directional stability of the tandem helicopter. Flight-test measurements of turns and oscillations, in conjunction with analytical studies, suggest possible practical methods of achieving the goals of satisfactory turn and oscillatory characteristics in the tandem helicopter.
Backward- and forward-looking responsibility for obesity: policies from WHO, the EU and England.

PubMed

Vallgårda, Signild; Nielsen, Morten Ebbe Juul; Hartlev, Mette; Sandøe, Peter

2015-10-01

In assigning responsibility for obesity prevention a distinction may be drawn between who is responsible for the rise in obesity prevalence ('backward-looking responsibility'), and who is responsible for reducing it ('forward-looking responsibility'). We study how the two aspects of responsibility figure in the obesity policies of WHO (European Region), the EU and the Department of Health (England). Responsibility for the emergence and reduction of obesity is assigned to both individuals and other actors to different degrees in the policies, combining an individual and a systemic view. The policies assign backward-looking responsibility to individuals, the social environment, the authorities and businesses. When it comes to forward-looking responsibility, individuals are expected to play a central role in reducing and preventing obesity, but other actors are also urged to act. WHO assigns to individuals the lowest degree of backward- and forward-looking responsibility, and the Department of Health (England) assigns them the highest degree of responsibility. Differences in the assignment of backward- and above all forward-looking responsibility could be explained to some extent by the different roles of the three authorities making the plans. WHO is a UN agency with health as its goal, the EU is a liberal economic union with optimization of the internal European market as an important task, and England, as an independent sovereign country, has its own economic responsibilities. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.
49. COMMAND INFORMATION CENTER (CIC) AFT LOOKING FORWARD PORT ...

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

49. COMMAND INFORMATION CENTER (CIC) - AFT LOOKING FORWARD PORT TO STARBOARD SHOWING VARIOUS TYPES OF RADAR UNITS, PLOT TABLES AND PLOTTING BOARDS. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
22. VIEW LOOKING FORWARD INTO CHAIN LOCKER FROM PORT SIDE ...

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

22. VIEW LOOKING FORWARD INTO CHAIN LOCKER FROM PORT SIDE ENTRY THROUGH CHAIN LOCKER BULKHEAD. PAWL BITT SHOWN IN FOREGROUND - Pilot Schooner "Alabama", Moored in harbor at Vineyard Haven, Vineyard Haven, Dukes County, MA
Compartment A123 crews WC (head) looking aft; to forward; note ...

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

Compartment A-123 crews WC (head) looking aft; to forward; note wire lockers for transient stowage of clothing while showering. (026) - USS Olympia, Penn's Landing, 211 South Columbus Boulevard, Philadelphia, Philadelphia County, PA
Light vehicle forward-looking, rear-end collision warning system performance guidelines

DOT National Transportation Integrated Search

1998-05-01

This document presents performance guidelines for forward-looking, rear-end collision warning systems (abbreviated FCW) for improving vehicular safety by preventing or mitigating vehicular rear-end collisions through driver notification or warning. T...
101. STARBOARD AIRPLANE ELEVATOR MACHINERY ROOM AFT LOOKING FORWARD ...

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

101. STARBOARD AIRPLANE ELEVATOR MACHINERY ROOM - AFT LOOKING FORWARD PORT TO STARBOARD SHOWING ELEVATOR ENGINE, LIFTING WIRES, HYDRAULIC PIPING WITH REMOTE OPERATOR. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
71. CHIEF PETTY OFFICERS' LOUNGE AFT LOOKING FORWARD PORT ...

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

71. CHIEF PETTY OFFICERS' LOUNGE - AFT LOOKING FORWARD PORT TO STARBOARD SHOWING COFFEE MESS, ICE CREAM COOLER, ICE MACHINE AND SCUTTLEBUTT. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA

Task and postural factors are related to back pain in helicopter pilots.

PubMed

Bridger, R S; Groom, M R; Jones, H; Pethybridge, R J; Pullinger, N

2002-08-01

A previous survey by Shear et al. revealed a high prevalence of back pain in Royal Navy helicopter aircrew, compared with controls. It was recommended that a second survey be undertaken, taking account of flying tasks and cockpit ergonomics. This was the purpose of the present investigation. A questionnaire containing items on back pain and posture was circulated to all 246 acting pilots, with returns of 75%. The questionnaire sought information on pain in both the flying pilot and co-pilot/instructor roles. The 12-mo prevalence of back pain was 80%. Task-related back pain was greatest in instrument flying (72%) and least in the co-pilot and instructor roles (24%). Self-ratings of posture indicated that forward flexed trunk postures predominated in the flying roles and were most extreme in instrument flying. In non-flying roles, symmetrical, reclining postures were more often reported. No demographic or psychosocial variables were significantly related to back pain prevalence or disability. Much of the back pain experienced by helicopter pilots appears to be due to the posture needed to operate the cyclic and collective controls. In instrument flying, it is suggested that the visual demands of scanning the displays may exacerbate the pain by causing the pilot to lean further forward.
Compact laser interferometer for translation and tilt measurement as optical readout for the LISA inertial sensor

NASA Astrophysics Data System (ADS)

Schuldt, Thilo; Gohlke, Martin; Weise, Dennis; Johann, Ulrich; Peters, Achim; Braxmaier, Claus

2007-10-01

The space mission LISA (Laser Interferometer Space Antenna) aims at detecting gravitational waves in the frequency range 30 μ Hz to 1Hz. Free flying proof masses inside the satellites act as inertial sensors and represent the end mirrors of the interferometer. In the current baseline design, LISA utilizes an optical readout of the position and tilt of the proof mass with respect to the satellite housing. This readout must have ~ 5pm/√Hz sensitivity for the translation measurement (for frequencies above 2.8mHz with an -2 relaxation down to 30 μHz) and ~ 10 nrad/√Hz sensitivity for the tilt measurement (for frequencies above 0.1mHz with an -1 relaxation down to 30 μHz). The University of Applied Sciences Konstanz (HTWG) - in collaboration with Astrium GmbH, Friedrichshafen, and the Humboldt-University Berlin - therefore develops a highly symmetric heterodyne interferometer implementing differential wavefront sensing for the tilt measurement. We realized a mechanically highly stable and compact setup. In a second, improved setup we measured initial noise levels below 5 pm/√Hz and 10 nrad/√Hz, respectively, for frequencies above 10mHz.
Arm locking with the GRACE follow-on laser ranging interferometer

NASA Astrophysics Data System (ADS)

Thorpe, James Ira; McKenzie, Kirk

2016-02-01

Arm locking is a technique for stabilizing the frequency of a laser in an interspacecraft interferometer by using the spacecraft separation as the frequency reference. A candidate technique for future space-based gravitational wave detectors such as the Laser Interferometer Space Antenna, arm locking has been extensive studied in this context through analytic models, time-domain simulations, and hardware-in-the-loop laboratory demonstrations. In this paper we show the laser ranging interferometer instrument flying aboard the upcoming Gravity Recovery and Climate Experiment follow-on (GRACE-FO) mission provides an appropriate platform for an on-orbit demonstration of the arm-locking technique. We describe an arm-locking controller design for the GRACE-FO system and a series of time-domain simulations that demonstrate its feasibility. We conclude that it is possible to achieve laser frequency noise suppression of roughly 2 orders of magnitude around a Fourier frequency of 1 Hz with conservative margins on the system's stability. We further demonstrate that "pulling" of the master laser frequency due to fluctuating Doppler shifts and lock acquisition transients is less than 100 MHz over several GRACE-FO orbits. These findings motivate further study of the implementation of such a demonstration.
General View looking forward along the centerline of the Orbiter ...

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

General View looking forward along the centerline of the Orbiter Discovery looking into the payload bay with a payload in the process of being secured into place. This photograph was taken in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
A Forward-Looking Approach

ERIC Educational Resources Information Center

McAllister, Edmond L.

1977-01-01

The current approach in teaching Japanese as a second language is questioned as inefficient. The forward-looking approach does not condition students to expect that they must learn all the items of a set before being able to learn anything else. (HP)
An experiment to test in-field pointing for Elisa

NASA Astrophysics Data System (ADS)

Brugger, Christina; Broll, Bernhard; Fitzsimons, Ewan; Johann, Ulrich; Jonke, Wouter; Lucarelli, Stefano; Nikolov, Susanne; Voert, Martijn; Weise, Dennis; Witvoet, Gert

2017-11-01

The evolved Laser Interferometer Space Antenna (eLISA) Mission is being developed to detect and characterise gravitational waves by measuring pathlength changes between free flying inertial test masses over a baseline of order 1 Gm. Here the observed astrophysical events and objects lie in a frequency range between 30 μHz and 1 Hz (the LISA measurement band, LMB).
34. PRIMARY FLIGHT CONTROL STATION AFT LOOKING FORWARD ON ...

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

34. PRIMARY FLIGHT CONTROL STATION - AFT LOOKING FORWARD ON PORT SIDE SHOWING FLIGHT DECK LIGHTING BOARD, ARRESTING GEAR CONTROL CONSOLE AND FRESNEL LENS OPTICAL LANDING SYSTEM. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
Characterization And Evaluation Of A Prototype Forward-Looking Automotive Radar (Flar), Final Report

DOT National Transportation Integrated Search

1997-03-01

This is the final report for a three-year Discretionary Cooperative Agreement with the National Highway Traffic Safety Administration (NHTSA Grant DTNH22-94-Y-17016), Characterization and Evaluation of a Forward-Looking automotive Radar Sensor....
Interior below decks in fish hold looking forward. Fish hatch ...

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

Interior below decks in fish hold looking forward. Fish hatch opening is at upper left, ceiling planks and knees at center and right. - Purse Seiner SHENANDOAH, Gig Harbor Peninsula Historical Society and Museum, Gig Harbor, Pierce County, WA
100. COBBLER SHOP AFT LOOKING FORWARD VISIBLE ARE ...

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

100. COBBLER SHOP - AFT LOOKING FORWARD - VISIBLE ARE THE FINISHING MACHINE, DAVIS STITCHING MACHINE, SINGER SEWING MACHINE FROM TAILOR SHOP, STORAGE SHELVES, WORK BENCH AND SHOE TREE STAND. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
118. #3 SHAFT ALLEY (PROPELLER SHAFT) FORWARD LOOKING AFT ...

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

118. #3 SHAFT ALLEY (PROPELLER SHAFT) - FORWARD LOOKING AFT ON PORT SIDE SHOWING THE SHAFT, SHAFT PACKING GLAND, SHAFT SEAL COOLING WATER LINE AND FIVE INCH FIRE MAIN PIPING. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
50 Years of Fermilab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lincoln, Don

America’s leading particle physics laboratory is turning 50 years old this year. Fermilab’s Dr. Don Lincoln remembers the laboratory’s first half century and looks forward to the fascinating research topics that Fermilab’s scientific staff are looking at as they leap forward into the future.
41. #1 ARRESTING GEAR ENGINE AFT LOOKING FORWARD PORT ...

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

41. #1 ARRESTING GEAR ENGINE - AFT LOOKING FORWARD PORT TO STARBOARD SHOWING ARRESTING GEAR ENGINE ACCUMULATOR, AIR FLASK, CONTROL VALVE, WITH CONTROL RAM, SHEAVES AND WIRES UNDERNEATH ENGINE STAND. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
73. TORPEDO WORK SHOP FORWARD LOOKING AFT SHOWING TORPEDO ...

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

73. TORPEDO WORK SHOP - FORWARD LOOKING AFT SHOWING TORPEDO ELEVATOR, HIGH PRESSURE AIR REDUCING STATION, SCUTTLEBUTT, TORPEDO AFTERBODY WORKSHOP, OVERHEAD CHAIN MOIST AND RAIL SYSTEM AND OVERHEAD SPRINKLER SYSTEM. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
Breaking in the Space Shuttle

NASA Astrophysics Data System (ADS)

Crippen, Robert L.

2002-01-01

I like to look forward, but I am also a great student of history. I believe there are many lessons, both positive and negative, that we can learn by looking back. Quite often, we tend to forget some of those. I'd like to speak a little bit about the era in which I entered the astronaut corps. I joined NASA in kind of a weird way-in the time period when everybody going into space was a test pilot. I was attending the Air Force Test Pilot School, even though I'm a Navy guy. In that time period, they were going through and selecting astronauts from the test pilot class, and I put my hand up and said, "I'd like to join." It turned out that both NASA and the Department of Defense were selecting astronauts, and, somewhere in the selection process, I ended up having to make a choice. There were lots of folks on the NASA list, and there weren't many folks on the Department of Defense list, so I figured that was my best chance to fly. So I said, "Send me to DoD for something called the Manned Orbital Laboratory," or MOL for short.
Multi-Axis Heterodyne Interferometry (MAHI)

NASA Astrophysics Data System (ADS)

Thorpe, James

The detection and measurement of gravitational waves represents humanity’s next, and final, opportunity to open an entirely new spectrum with which to view the universe. The first steps of this process will likely take place later this decade when the second-generation ground-based instruments such as Advanced LIGO approach design sensitivity. While these events will be historic, it will take a space-based detector to access the milliHertz gravitational wave frequency band, a band that is rich in both number and variety of sources. The Laser Interferometer Space Antenna (LISA) concept has been developed over the past two decades in the US and Europe to provide access to this band. The European Space Agency recently selected The Gravitational Universe as the science theme for the 3rd Large-class mission in the Cosmic Visions Programme, with the assumption that a LISA-like instrument would be implemented for launch in 2034. NASA has expressed interest in partnering on this effort and the US community has made its own judgment on the scientific potential of a space-based gravitational wave observatory through the selection of LISA as the 3rd flagship mission in the 2010 Decadal Survey. Much of the effort has been in retiring risk for the unique technologies that comprise a gravitational wave detector. A prime focus of this effort is LISA Pathfinder (LPF), a dedicated technology demonstrator mission led by ESA with contributions from NASA and several member states. LPF’s primary objective is to validate drag-free flight as an approach to realizing an inertial reference mass. Along the way, several important technologies will be demonstrated, including picometer-level heterodyne interferometry. However, there are several important differences between the interferometry design for LISA and that for LPF. These mostly result from the fact that LISA interferometry involves multiple lasers on separate spacecraft whereas LPF can use a single laser on a single spacecraft. We propose to develop a laboratory prototype of a LISA-like interferometric metrology system capable of simultaneously making picometer-level position and nanoradian-level attitude measurements of a free-flying target. In the LISA application, this prototype would represent the short-arm interferometer, measuring the displacement and relative attitude between the gravitational test mass and the spacecraft. This measurement is used both to drive the drag-free attitude and control system as well as to extract the gravitational wave science signal. In addition to the LISA application, such a system would have broader applications in future geodesy and formation-flying missions. The prototype free-flying metrology system will consist of the following subcomponents: an optical bench providing stable pathlengths, an optical target mounted on a precision actuator, a low-noise quadrant photoreceiver for generating differential wavefront signals, and a phase measurement system to measure the individual heterodyne signals and convert them into quantities such as position and angle. In addition to the moving target, the optical bench will include a pair of fixed targets to be used as references. Comparing the two reference interferometers will provide an estimate of the noise performance of the measurement system, while comparing a reference interferometer with the free-flying target will allow us to demonstrate measurement over a large dynamic range. In addition to making performance measurements, we will use this prototype system to explore a number of system-level issues related to free-flying interferometry including initial acquisition, beam-walk effects, and jitter couplings.
Searching for life with the Terrestrial Planet Finder: Lagrange point options for a formation flying interferometer

NASA Technical Reports Server (NTRS)

Beichman, C.; Gomez, G.; Lo, M.; Masdemont, J.; Romans, L.

2002-01-01

In this paper, we describe the mission design for TPF assuming a distributed spacecraft concept using formation flight around both a halo orbit around L2 as well as a heliocentric orbit. Although the mission architecture is still under study, the next two years will include study of four design cncepts and a downselect to two concepts around 2005.
Technology Plan for the Terrestrial Planet Finder Interferometer

NASA Technical Reports Server (NTRS)

Lawson, Peter R. (Editor); Dooley, Jennifer A. (Editor)

2005-01-01

The technology plan for the Terrestrial Planet Finder Interferometer (TPF-I) describes the breadth of technology development currently envisaged to enable TPF-I to search for habitable worlds around nearby stars. TPF-I is currently in Pre-Phase A (the Advanced Study Phase) of its development. For planning purposes, it is expected to enter into Phase A in 2010 and be launched sometime before 2020. TPF-I is being developed concurrently with the Terrestrial Planet Finder Coronagraph (TPF-C), whose launch is anticipated in 201 6. The missions are being designed with the capability to detect Earth-like planets should they exist in the habitable zones of Sun-like (F,G, and K) stars out to a distance of about 60 light-years. Each mission will have the starlight-suppression and spectroscopic capability to enable the characterization of extrasolar planetary atmospheres, identifying biomarkers and signs of life. TPF-C is designed as a visible-light coronagraph; TPF-I is designed as a mid-infrared formation-flying interferometer. The two missions, working together, promise to yield unambiguous detections and characterizations of Earth-like planets. The challenges of planet detections with mid-infrared formation-flying interferometry are described within this technology plan. The approach to developing the technology is described through roadmaps that lead from our current state of the art through the different phases of mission development to launch. Technology metrics and milestones are given to measure progress. The emphasis of the plan is development and acquisition of technology during pre-Phase A to establish feasibility of the mission to enter Phase A sometime around 2010. Plans beyond 2010 are outlined. The plan contains descriptions of the development of new component technology as well as testbeds that demonstrate the viability of new techniques and technology required for the mission. Starlight-suppression (nulling) and formation-flying technology are highlighted. Although the techniques are described herein, the descriptions are only at a high-level, and tutorial material is not included. The reader is expected to have some familiarity with the principles of long-baseline mid-infrared interferometry. Selected references to existing literature are given where relevant.
11. VIEW LOOKING FORWARD ON PORT SIDE OF MAIN DECK ...

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

11. VIEW LOOKING FORWARD ON PORT SIDE OF MAIN DECK FROM POINT NEAR AFT COMPANIONWAY. DECKHOUSES, FROM RIGHT TO LEFT (STERN TO BOW), ARE ENGINE ROOM SKYLIGHT AND GALLEY SKYLIGHT/COMPANIONWAY - Pilot Schooner "Alabama", Moored in harbor at Vineyard Haven, Vineyard Haven, Dukes County, MA
22. VIEW SHOWING CREW'S QUARTERS IN FORECASTLE, LOOKING FORWARD FROM ...

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

22. VIEW SHOWING CREW'S QUARTERS IN FORECASTLE, LOOKING FORWARD FROM DOOR IN PORT SIDE OF BULKHEAD; BUNK FRAME, (LEFT IN VIEW), REMAINS OF SMALL CAST IRON STOVE NEAR DECK STANCHION (CENTER OF VIEW) - Bugeye "Louise Travers", Intersection of Routes 2 & 4, Solomons, Calvert County, MD

28. SONAR CONTROL ROOM FORWARD LOOKING AFT SHOWING AN/SQS23G ...

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

28. SONAR CONTROL ROOM - FORWARD LOOKING AFT SHOWING AN/SQS-23G DETECTING-RANGING SET, MARK & CONTROL PANEL, CAN-55134 RECORDER, SPEED INDICATOR, VARIOUS ALARMS AND INTERNAL COMMUNICATION CIRCUITS. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
Design Enhancements of the Fourier Kelvin Stellar Interferometer to Enable Detection of Earth Twins

NASA Technical Reports Server (NTRS)

Barry, Richard K.; Danchi, William C.; Lopez, Bruno; Rinehart, Stephan; Augereau, Jean-Charles; Beust, Herve; Bonfils, Xavier; Borde, Pascal; Kern, Pierre; Leger, Alain;

2009-01-01

During the last few years, considerable effort has been directed towards very large-scale (> $5 billion) missions to detect and characterize Mars-radius to Earth-radius planets around nearby stars; such as the Terrestrial Planet Finder Interferometer and Darwin missions. However, technological issues such as formation flying and control of systematic noise sources will likely prevent these missions from entering Phase A until at least the end of the next decade. Presently more than 350 planets have been discovered by a variety of techniques, and little is known about the majority of them other than their approximate mass. However, a simplified nulling interferometer operating in the near- to mid-infrared (e.g. approx. 5-15 microns), like the enhanced version of the Fourier Kelvin Stellar Interferometer (FKSI), can characterize the atmospheres of a large sample of the known planets - including Earth twins. Many other scientific problems can be addressed with a system like FKSI, including the studies of debris disks, active galactic nuclei, and low mass companions around nearby stars. We report results of a recent engineering study on an enhanced version of FKSI that includes 1-meter primary mirrors, 20-meter boom length, and an advanced sun shield that will provide a 45-degree FOR and 40K operating temperature for all optics including siderostats.

Explosive component acceptance tester using laser interferometer technology

NASA Technical Reports Server (NTRS)

Wickstrom, Richard D.; Tarbell, William W.

1993-01-01

Acceptance testing of explosive components requires a reliable and simple to use testing method that can discern less than optimal performance. For hot-wire detonators, traditional techniques use dent blocks or photographic diagnostic methods. More complicated approaches are avoided because of their inherent problems with setup and maintenance. A recently developed tester is based on using a laser interferometer to measure the velocity of flying plates accelerated by explosively actuated detonators. Unlike ordinary interferometers that monitor displacement of the test article, this device measures velocity directly and is commonly used with non-spectral surfaces. Most often referred to as the VISAR technique (Velocity Interferometer System for Any Reflecting Surface), it has become the most widely-accepted choice for accurate measurement of velocity in the range greater than 1 mm/micro-s. Traditional VISAR devices require extensive setup and adjustment and therefore are unacceptable in a production-testing environment. This paper describes a new VISAR approach which requires virtually no adjustments, yet provides data with accuracy comparable to the more complicated systems. The device, termed the Fixed-Cavity VISAR, is currently being developed to serve as a product verification tool for hot-wire detonators and slappers. An extensive data acquisition and analysis computer code was also created to automate the manipulation of raw data into final results.
76 FR 80941 - Request for Connect America Fund Cost Models

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-27

... interested parties to submit forward-looking cost models, consistent with the USF/ICC Transformation Order... forward-looking cost model consistent with the USF/ICC Transformation Order no later than December 30.... SUPPLEMENTARY INFORMATION: 1. On November 18, 2011, the Commission released the USF/ICC Transformation Order, 76...
Compartment A20 construction stories locker looking from forward to aft ...

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

Compartment A-20 construction stories locker looking from forward to aft showing wooden ladder and storage bins. Heavy frame supports armored protective deck. Armor plate hatch at top left penetrates protective deck. (05) - USS Olympia, Penn's Landing, 211 South Columbus Boulevard, Philadelphia, Philadelphia County, PA
21. VIEW LOOKING FORWARD INTO STARBOARD SIDE OF CHAIN LOCKER ...

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

21. VIEW LOOKING FORWARD INTO STARBOARD SIDE OF CHAIN LOCKER FROM CHAIN LOCKER BULKHEAD; PAWL BITT SHOWN IN EXTREME LEFT FOREGROUND, WITH APRON IN BACKGROUND. BREASTHOOK, SHELF AND CLAMP SHOWN AT TOP OF IMAGE - Pilot Schooner "Alabama", Moored in harbor at Vineyard Haven, Vineyard Haven, Dukes County, MA
Extending the Computer Revolution into Space

NASA Technical Reports Server (NTRS)

Deutsch, Leslie J.

1999-01-01

The computer revolution is far from over on Earth. It is just beginning in space. We can look forward to an era of enhanced scientific exploration of the solar system and even other start systems. We can look forward to the benefits of this space revolution to commercial uses on and around Earth.
Welfare Reform when Recipients Are Forward-Looking

ERIC Educational Resources Information Center

Swann, Christopher A.

2005-01-01

By studying recipients of aid under the Temporary Assistance for Needy Families (TANF) welfare scheme, the effect of time limits of welfare schemes on forward looking recipients is assessed using a discrete-choice dynamic programming framework model. The policy simulations for the preferred specification of utility reveal that two year time limits…
Functions and Mechanism of Sleep in Flies and Mammals

DTIC Science & Technology

2005-02-01

laboratory who is pursuing the aim. Aim 1: To identify the molecular targets of the wakefulness-promoting drug modafinil using forward genetics in...effects of many sleep modulating compounds are thought to be conserved. Our initial intention was to investigate the effects of Modafinil on fly sleep...Hendricks, J. C., Kirk, D., Panckeri, K., Miller, M. S., and Pack, A. I. (2003). Modafinil maintains waking in the fruit fly drosophila melanogaster. Sleep
Superconductivity: Recent Developments and Defence Applications

DTIC Science & Technology

1988-03-11

resonance tomography ; quantum interferometers used in detectors for research into biomagnetism and gravitational waves; and analogue electronics devices...has looked at muon spin rotation measurements of the penetration depth of magnetic fields into the superconductors. Basic research is under way at Chalk
A system definition study for the Advanced Meteorological Temperature Sounder (AMTS)

NASA Technical Reports Server (NTRS)

1977-01-01

The functional requirements of Exhibit A (11) were used as the baseline for the conceptual design of a fixed grating out of plane multidetector spectrometer for the Space Shuttle application. Because the grating instrument would be large and the 28 element detector array would be difficult to cool radiatively from a free flying spacecraft and because increasing the spectral resolution of the grating instrument would be difficult in an instrument of reasonable size, a parallel study of a Nichelson interferometer spectrometer was undertaken. This type of instrument offers compact size, fewer detectors to cool, and the possibility of increased spectral resolution. The design and performance parameters of both the grating and interferometer approaches are described. The tradeoffs involved in comparing the two systems for sounding applications are discussed.
Detecting ultralight axion dark matter wind with laser interferometers

NASA Astrophysics Data System (ADS)

Aoki, Arata; Soda, Jiro

The ultralight axion with mass around 10-22eV is known as a candidate of dark matter. A peculiar feature of the ultralight axion is oscillating pressure in time, which produces oscillation of gravitational potentials. Since the solar system moves through the dark matter halo at the velocity of about v ˜ 300km/s = 10-3, there exists axion wind, which looks like scalar gravitational waves for us. Hence, there is a chance to detect ultralight axion dark matter with a wide mass range by using laser interferometer detectors. We calculate the detector signal induced by the oscillating pressure of the ultralight axion field, which would be detected by future laser interferometer experiments. We also argue that the detector signal can be enhanced due to the resonance in modified gravity theory explaining the dark energy.
Wind shear detection. Forward-looking sensor technology

NASA Technical Reports Server (NTRS)

Bracalente, E. M. (Compiler); Delnore, V. E. (Compiler)

1987-01-01

A meeting took place at NASA Langley Research Center in February 1987 to discuss the development and eventual use of forward-looking remote sensors for the detection and avoidance of wind shear by aircraft. The participants represented industry, academia, and government. The meeting was structured to provide first a review of the current FAA and NASA wind shear programs, then to define what really happens to the airplane, and finally to give technology updates on the various types of forward-looking sensors. This document is intended to informally record the essence of the technology updates (represented here through unedited duplication of the vugraphs used), and the floor discussion following each presentation. Also given are key issues remaining unresolved.
10. VIEW LOOKING FORWARD ON STARBOARD SIDE OF MAIN DECK ...

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

10. VIEW LOOKING FORWARD ON STARBOARD SIDE OF MAIN DECK FROM POINT NEAR ENGINE CONTROL PANEL. DECKHOUSES, FROM LEFT TO RIGHT (STERN TO BOW), ARE AFT COMPANIONWAY, PILOTS' CABIN SKYLIGHT, ENGINE ROOM SKYLIGHT, AND GALLEY SKYLIGHT/COMPANIONWAY - Pilot Schooner "Alabama", Moored in harbor at Vineyard Haven, Vineyard Haven, Dukes County, MA
19. Interior first level view looking north within forward (north) ...

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

19. Interior first level view looking north within forward (north) section of firing pier. Objects pictured include torpedo cart (left), floor-mounted roller tray (extending to lower right), and (at center rear), deck-type firing tube. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI
64. FORWARD EMERGENCY DIESEL GENERATOR SET STARBOARD LOOKING TO ...

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

64. FORWARD EMERGENCY DIESEL GENERATOR SET - STARBOARD LOOKING TO PORT SHOWING BOTTOM HALF OF FAIRBANKS MORSE 36D81/8 TEN CYLINDER DIESEL ENGINE SERIAL #951230 AND GENERAL ELECTRIC 1,000KW GENERATOR KVA 1250, RPM 720, SERIAL #6920274. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
20. HANGAR BAY #2 FORWARD LOOKING AFT ON CENTERLINE ...

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

20. HANGAR BAY #2 - FORWARD LOOKING AFT ON CENTERLINE - STARBOARD SIDE SHOWING CONFLAGRATION STATION, UPTAKE SPACE AND DEHUMIDIFICATION MACHINES - PORT SIDE SHOWING VARIOUS DECK WINCHES, ROLLER DOORS, HANGAR DECK PLANE CONTROL STATION AND AQUEOUS FIRE FIGHTING FOAM HOSE REELS. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
Is the Mind Inherently Forward-Looking? Comparing Prediction and Retrodiction

ERIC Educational Resources Information Center

Jones, Jason; Pashler, Harold

2007-01-01

It has been suggested that prediction may be an organizing principle of the mind and/or the neocortex, with cognitive machinery specifically engineered to detect forward-looking temporal relationships, rather than merely associating temporally contiguous events. There is a remarkable absence of behavioral tests of this idea, however. To address…
Windshear database for forward-looking systems certification

NASA Technical Reports Server (NTRS)

Switzer, G. F.; Proctor, F. H.; Hinton, D. A.; Aanstoos, J. V.

1993-01-01

This document contains a description of a comprehensive database that is to be used for certification testing of airborne forward-look windshear detection systems. The database was developed by NASA Langley Research Center, at the request of the Federal Aviation Administration (FAA), to support the industry initiative to certify and produce forward-look windshear detection equipment. The database contains high resolution, three dimensional fields for meteorological variables that may be sensed by forward-looking systems. The database is made up of seven case studies which have been generated by the Terminal Area Simulation System, a state-of-the-art numerical system for the realistic modeling of windshear phenomena. The selected cases represent a wide spectrum of windshear events. General descriptions and figures from each of the case studies are included, as well as equations for F-factor, radar-reflectivity factor, and rainfall rate. The document also describes scenarios and paths through the data sets, jointly developed by NASA and the FAA, to meet FAA certification testing objectives. Instructions for reading and verifying the data from tape are included.
Neural network approximation of nonlinearity in laser nano-metrology system based on TLMI

NASA Astrophysics Data System (ADS)

Olyaee, Saeed; Hamedi, Samaneh

2011-02-01

In this paper, an approach based on neural network (NN) for nonlinearity modeling in a nano-metrology system using three-longitudinal-mode laser heterodyne interferometer (TLMI) for length and displacement measurements is presented. We model nonlinearity errors that arise from elliptically and non-orthogonally polarized laser beams, rotational error in the alignment of laser head with respect to the polarizing beam splitter, rotational error in the alignment of the mixing polarizer, and unequal transmission coefficients in the polarizing beam splitter. Here we use a neural network algorithm based on the multi-layer perceptron (MLP) network. The simulation results show that multi-layer feed forward perceptron network is successfully applicable to real noisy interferometer signals.

Preliminary Study Using Forward Reaction Control System Jets During Space Shuttle Entry

NASA Technical Reports Server (NTRS)

Restrepo, Carolina; Valasek, John

2006-01-01

Failure or degradation of the flight control system, or hull damage, can lead to loss of vehicle control during entry. Possible failure scenarios are debris impact and wing damage that could result in a large aerodynamic asymmetry which cannot be trimmed out without additional yaw control. Currently the space shuttle uses aerodynamic control surfaces and Reaction Control System jets to control attitude. The forward jets are used for orbital maneuvering only, while the aft jets are used for yaw control during entry. This paper develops a controller for using the forward reaction control system jets as an additional control during entry, and assesses its value and feasibility during failure situations. Forward-aft jet blending logic is created, and implemented on a simplified model of the space shuttle entry flight control system. The model is validated and verified on the nonlinear, six degree-of-freedom Shuttle Engineering Simulator. A rudimentary human factors study was undertaken using the forward cockpit simulator at Johnson Space Center, to assess flying qualities of the new system and pilot workload. Results presented in the paper show that the combination of forward and aft jets provides useful additional yaw control, in addition to potential fuel savings and the ability to balance the use of the fuel in the forward and aft tanks to meet availability constraints of both forward and aft fuel tanks. Piloted simulation studies indicated that using both sets of jets while flying a damaged space shuttle reduces pilot workload, and makes the vehicle more responsive.
RECON - A New Way Forward

Science.gov Websites

Us Recon - New Way Forward "A New Way Forward" takes an in-depth look at Operation Iraqi News Embassy of the United States - Baghdad, Iraq Operation Iraqi Freedom - Freguently Asked Questions
United States Air Force F-35A Operational Basing Environmental Impact Statement. Appendix E: Comments

DTIC Science & Technology

2013-09-01

surrounding states are truely in a unique position to contribute to the needs of the nation and I look forward to the outcome of the Enviromental ...to the needs of the nation and I look forward to the outcome of the Enviromental Impact Statement and subsequent Record of Decision. Thank you for
Forward Looking Needs Systematised Megatrends in Suitable Granularity

ERIC Educational Resources Information Center

Ahamer, Gilbert

2014-01-01

Purpose: The purpose of this paper is to inquire about the applicability of the concept of granularity to the necessity of future research or--as often called in the European Union--forward looking (FL). After theoretical deliberation, it uses a planned world-wide information system as a case study for applying the notion of granularity regarding…
Alternative Fuels Data Center: Greater Portland Transit District Looks

Science.gov Websites

Forward with Natural GasA> Greater Portland Transit District Looks Forward with Natural Gas to , Maine, powers its transit vehicles with compressed natural gas. For information about this project Related Videos Photo of a car Hydrogen Powers Fuel Cell Vehicles in California Nov. 18, 2017 Photo of a
Estimating Welfare Effects Consistent with Forward-Looking Behavior. Part I: Lessons from a Simulation Exercise. Part II: Empirical Results.

ERIC Educational Resources Information Center

Keane, Michael P.; Wolpin, Kenneth I.

2002-01-01

Part I uses simulations of a model of welfare participation and women's fertility decisions, showing that increases in per-child payments have substantial impact on fertility. Part II uses estimations of decision rules of forward-looking women regarding welfare participation, fertility, marriage, work, and schooling. (SK)
Looking Forward: Increased Attention to LGBTQ Students and Families in Middle Grade Classrooms

ERIC Educational Resources Information Center

Wickens, Corrine M.; Wedwick, Linda

2011-01-01

Looking backwards, discussions around sexual orientation and sexual identity have been noticeably absent at the middle grades. As a result, middle grade teachers may find it difficult to know how to effectively select age-appropriate materials that include LGBTQ issues and content. To move the field forward, the authors specifically highlight four…
30. VIEW LOOKING FORWARD ON STARBOARD SIDE OF MAIN DECK ...

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

30. VIEW LOOKING FORWARD ON STARBOARD SIDE OF MAIN DECK FROM ALONGSIDE ENGINE CONTROL PANEL. CONFIGURATION OF SKYLIGHTS AND COMPANIONWAY DIFFERENT FROM WHAT WAS FOUND BY HAER IN 1986. Original 4-3/4'x6-3/4' photograph taken c. 1930? - Pilot Schooner "Alabama", Moored in harbor at Vineyard Haven, Vineyard Haven, Dukes County, MA
General view looking forward from the starboard side of the ...

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

General view looking forward from the starboard side of the Orbiter Discovery looking into the payload bay and the bulkhead of the forward fuselage with the airlock. The docking ring and airlock hatches have been removed from the airlock prior to this photo being taken. Note that the Orbiter Boom Sensor System is still attached while the Remote Manipulator System has been removed. Also note the suspended protective panels and walkways in place to protect the interior surfaces of the payload bay doors while in their open position. This view was taken from a service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
A high-speed tunable beam splitter for feed-forward photonic quantum information processing.

PubMed

Ma, Xiao-Song; Zotter, Stefan; Tetik, Nuray; Qarry, Angie; Jennewein, Thomas; Zeilinger, Anton

2011-11-07

We realize quantum gates for path qubits with a high-speed, polarization-independent and tunable beam splitter. Two electro-optical modulators act in a Mach-Zehnder interferometer as high-speed phase shifters and rapidly tune its splitting ratio. We test its performance with heralded single photons, observing a polarization-independent interference contrast above 95%. The switching time is about 5.6 ns, and a maximal repetition rate is 2.5 MHz. We demonstrate tunable feed-forward operations of a single-qubit gate of path-encoded qubits and a two-qubit gate via measurement-induced interaction between two photons.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Porter, Edward K.; Cornish, Neil J.

Massive black hole binaries are key targets for the space based gravitational wave Laser Interferometer Space Antenna (LISA). Several studies have investigated how LISA observations could be used to constrain the parameters of these systems. Until recently, most of these studies have ignored the higher harmonic corrections to the waveforms. Here we analyze the effects of the higher harmonics in more detail by performing extensive Monte Carlo simulations. We pay particular attention to how the higher harmonics impact parameter correlations, and show that the additional harmonics help mitigate the impact of having two laser links fail, by allowing for anmore » instantaneous measurement of the gravitational wave polarization with a single interferometer channel. By looking at parameter correlations we are able to explain why certain mass ratios provide dramatic improvements in certain parameter estimations, and illustrate how the improved polarization measurement improves the prospects for single interferometer operation.« less
Aversive Learning and Appetitive Motivation Toggle Feed-Forward Inhibition in the Drosophila Mushroom Body.

PubMed

Perisse, Emmanuel; Owald, David; Barnstedt, Oliver; Talbot, Clifford B; Huetteroth, Wolf; Waddell, Scott

2016-06-01

In Drosophila, negatively reinforcing dopaminergic neurons also provide the inhibitory control of satiety over appetitive memory expression. Here we show that aversive learning causes a persistent depression of the conditioned odor drive to two downstream feed-forward inhibitory GABAergic interneurons of the mushroom body, called MVP2, or mushroom body output neuron (MBON)-γ1pedc>α/β. However, MVP2 neuron output is only essential for expression of short-term aversive memory. Stimulating MVP2 neurons preferentially inhibits the odor-evoked activity of avoidance-directing MBONs and odor-driven avoidance behavior, whereas their inhibition enhances odor avoidance. In contrast, odor-evoked activity of MVP2 neurons is elevated in hungry flies, and their feed-forward inhibition is required for expression of appetitive memory at all times. Moreover, imposing MVP2 activity promotes inappropriate appetitive memory expression in food-satiated flies. Aversive learning and appetitive motivation therefore toggle alternate modes of a common feed-forward inhibitory MVP2 pathway to promote conditioned odor avoidance or approach. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.
Internet Architecture: Lessons Learned and Looking Forward

DTIC Science & Technology

2006-12-01

Internet Architecture: Lessons Learned and Looking Forward Geoffrey G. Xie Department of Computer Science Naval Postgraduate School April 2006... Internet architecture. Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of information is...readers are referred there for more information about a specific protocol or concept. 2. Origin of Internet Architecture The Internet is easily
19. On salon deck level, view looking forward at tops ...

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

19. On salon deck level, view looking forward at tops of steam chimneys (rising from boilers) showing safety valves, safety valve vent pipe, and smoke bonnet underneath smokestack. Steam chimneys are integral parts of the boilers and in effect are smokestacks surrounded by a pressurized steam space continuous with the boiler steam spaces. - Ferry TICONDEROGA, Route 7, Shelburne, Chittenden County, VT
Forward Looking: Structural Change and Institutions in Highestincome Countries and Globally

ERIC Educational Resources Information Center

Ahamer, Gilbert; Mayer, Johannes

2013-01-01

Purpose: Structural economic shifts are a key sign of development in all stages globally; and these shifts may also result in the changing roles of institutions. The purpose of this paper is to quantitatively analyse trends that may be used for so-called forward looking and makes use of them to recommend strategies for reorganising institutions.…
Closeup view of the aft fuselage looking forward along the ...

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

Close-up view of the aft fuselage looking forward along the approximate centerline of the Orbiter Discovery looking at the expansion nozzles of the Space Shuttle Main Engines (SSME) and the Orbiter Maneuvering System. Also in the view is the orbiter's body flap with a protective covering over the High-temperature Reusable Surface Insulation tiles on the surface facing the SSMEs. This image was taken inside the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Orion EM-1 Forward Skirt Move from Hangar AF to BFF

NASA Image and Video Library

2017-08-30

The Exploration Mission-1 (EM-1) left-hand forward skirt for NASA's Space Launch System (SLS) solid rocket boosters arrives inside the high bay at the Booster Fabrication Facility (BFF) at NASA's Kennedy Space Center in Florida. In the BFF, the forward skirt will be inspected and prepared for use on the left-hand solid rocket booster for EM-1. NASA's Orion spacecraft will fly atop the SLS rocket on its first uncrewed flight test.
Richard G. Ewers

NASA Image and Video Library

1998-12-02

Richard G. (Dick) Ewers became a pilot in the Flight Crew Branch of NASA's Dryden Flight Research Center, Edwards, California, in May 1998. His flying duties focus on operation of the Airborne Science DC-8 and Systems Research F/A-18 aircraft, but he also maintains qualifications in the King Air and T-34C. He has more than 32 years and nearly 9,000 hours of military and civilian flight experience in all types of aircraft from jet fighters to blimps. Ewers came to NASA Dryden from a position as an engineering test pilot with Northrop Grumman's Electronic Sensors and Systems Division (formerly Westinghouse's Electronic Systems Group). He spent eight and a half years with Westinghouse flight testing radar and forward looking infrared systems under development for military and civilian use. Before going to work for Westinghouse, Ewers served for more than 21 years as a U.S. Marine Corps fighter and test pilot, flying F-4, A-4, and F/A-18 aircraft. He underwent flight training at Naval Air Station Pensacola, Fla., in 1969-70. He was subsequently assigned to both fighter/attack and reconnaissance squadrons before ultimately commanding an F-4S squadron for two years. Additionally, his flying included combat service in Vietnam and operational exchange tours with both U.S. Navy and U.S. Air Force squadrons flying F-4s around the world, including off aircraft carriers. Ewers graduated from the U.S. Naval Test Pilot School in 1981 and subsequently served two tours as a test pilot at the Naval Air Test Center, Patuxent River, Md. Most of his flight test experience was with the F/A-18 Hornet. He retired from the Marine Corps in 1989 with the rank of lieutenant colonel. Ewers graduated from the U.S. Air Force Academy in 1968 with a bachelor of science degree in engineering mechanics. He earned a master of science degree in aeronautical systems from the University of West Florida in 1970.
Commander Brand and Pilot Overmyer operate controls on forward flight deck

NASA Technical Reports Server (NTRS)

1982-01-01

On forward flight deck, Commander Brand and Pilot Overmyer operate controls from commanders and pilots seats. Overall view taken from the aft flight deck looking forward shows both astronauts reviewing procedures and checking CRT screen data.
It's Our Move Now: A Community Action Guide to the UN Nairobi Forward-Looking Strategies for the Advancement of Women.

ERIC Educational Resources Information Center

Sandler, Joanne

This community action guide was developed to implement the strategies for the advancement of women developed at the United Nations world conference in Nairobi that ended the Decade for Women in 1985. The guide is intended to: (1) increase understanding and awareness of the existence of the Nairobi Forward-Looking Strategies for the Advancement of…

Nairobi Forward-looking Strategies for the Advancement of Women: Issues and the Canadian Situation. Fact Sheets--1992 Update.

ERIC Educational Resources Information Center

Status of Women Canada, Ottawa (Ontario).

The 1992 edition of the fact sheets provides information on new and revised Canadian government programs and policies about the implementation of the Nairobi Forward-looking Strategies for the Advancement of Women program that were adopted at the United Nations World Conference on Women in Kenya in 1985. This edition continues to address the…
High stability laser for next generation gravity missions

NASA Astrophysics Data System (ADS)

Nicklaus, K.; Herding, M.; Wang, X.; Beller, N.; Fitzau, O.; Giesberts, M.; Herper, M.; Barwood, G. P.; Williams, R. A.; Gill, P.; Koegel, H.; Webster, S. A.; Gohlke, M.

2017-11-01

With GRACE (launched 2002) and GOCE (launched 2009) two very successful missions to measure earth's gravity field have been in orbit, both leading to a large number of publications. For a potential Next Generation Gravity Mission (NGGM) from ESA a satellite-to-satellite tracking (SST) scheme, similar to GRACE is under discussion, with a laser ranging interferometer instead of a Ka-Band link to enable much lower measurement noise. Of key importance for such a laser interferometer is a single frequency laser source with a linewidth <10 kHz and extremely low frequency noise down to 40 Hz / √Hz in the measurement frequency band of 0.1 mHz to 1 Hz, which is about one order of magnitude more demanding than LISA. On GRACE FO a laser ranging interferometer (LRI) will fly as a demonstrator. The LRI is a joint development between USA (JPL,NASA) and Germany(GFZ,DLR). In this collaboration the JPL contributions are the instrument electronics, the reference cavity and the single frequency laser, while STI as the German industry prime is responsible for the optical bench and the retroreflector. In preparation of NGGM an all European instrument development is the goal.
The Balloon Experimental Twin Telescope for Infrared Interferometry

NASA Technical Reports Server (NTRS)

Rinehart, Stephen A.

2008-01-01

Astronomical studies at infrared wavelengths have dramatically improved our understanding of the universe, and observations with Spitzer, the upcoming Herschel mission, and SOFIA will continue to provide exciting new discoveries. The relatively low angular resolution of these missions, however, is insufficient to resolve the physical scales on which mid- to far-infrared emission arises, resulting in source and structure ambiguities that limit our ability to answer key science questions. Interferometry enables high angular resolution at these wavelengths, a powerful tool for scientific discovery, We will build the Balloon Experimental Twin Telescope for Infrared Interferometry (BETII), an eight-meter baseline Michelson stellar interferometer to fly on a high-altitude balloon. BETTII's spectral-spatial capability, provided by an instrument using double-Fourier techniques, will address key questions about the nature of disks in young star clusters and active galactic nuclei and the envelopes of evolved stars. BETTII will also lay the technological groundwork for future space interferometers,
The use of a cubesat to validate technological bricks in space

NASA Astrophysics Data System (ADS)

Rakotonimbahy, E.; Vives, S.; Dohlen, K.; Savini, G.; Iafolla, V.

2017-11-01

In the framework of the FP7 program FISICA (Far Infrared Space Interferometer Critical Assessment), we are developing a cubesat platform which will be used for the validation in space of two technological bricks relevant for FIRI. The first brick is a high-precision accelerometer which could be used in a future space mission as fundamental element for the dynamic control loop of the interferometer. The second brick is a miniaturized version of an imaging multi-aperture telescope. Ultimately, such an instrument could be composed of numerous space-born mirror segments flying in precise formation on baselines of hundreds or thousands of meters, providing high-resolution glimpses of distant worlds. We are proposing to build a very first space-born demonstrator of such an instrument which will fit into the limited resources of one cubesat. In this paper, we will describe the detailed design of the cubesat hosting the two payloads.
The optical very large array and its moon-based version

NASA Technical Reports Server (NTRS)

Labeyrie, Antoine

1992-01-01

An Optical Very Large Array (OVLA) is currently in early prototyping stages for ground-based sites, such as Mauna Kea and perhaps the VLT site in Chile. Its concept is also suited for a moon-based interferometer. With a ring of bi-dimensionally mobile telescopes, there is maximal flexibility in the aperture pattern, and no need for delay lines. A circular configuration of many free-flying telescopes, TRIO, is also considered for space interferometers. Finally, the principle of gaseous mirrors may become applicable for moon-based optical arrays. Fifteen years after the first coherent linkage of two optical telescopes, the design of an ambitious imaging array, the OVLA, is now well advanced. Two 1.5 m telescopes have been built and now provide astronomical results. Elements of the OVLA are under construction. Although primarily conceived for ground-based sites, the OVLA structure appears to meet the essential requirements for operation on the Moon.
Research on thermal protection mechanism of forward-facing cavity and opposing jet combinatorial thermal protection system

NASA Astrophysics Data System (ADS)

Lu, Hai-Bo; Liu, Wei-Qiang

2014-04-01

Validated by the correlated experiments, a nose-tip with forward-facing cavity/opposing jet/the combinatorial configuration of forward-facing cavity and opposing jet thermal protection system (TPS) are investigated numerically. The physical mechanism of these TPS is discussed, and the cooling efficiency of them is compared. The combinatorial system is more suitable to be the TPS for the high speed vehicles which need fly under various flow conditions with long-range and long time.
Orion EM-1 Forward Skirt Move from Hangar AF to BFF

NASA Image and Video Library

2017-08-30

The Exploration Mission-1 (EM-1) left-hand forward skirt for NASA's Space Launch System (SLS) solid rocket boosters arrives at the entrance to the high bay at the Booster Fabrication Facility (BFF) at NASA's Kennedy Space Center in Florida. In the BFF, the forward skirt will be inspected and prepared for use on the left-hand solid rocket booster for EM-1. NASA's Orion spacecraft will fly atop the SLS rocket on its first uncrewed flight test.
Orion EM-1 Forward Skirt Move from Hangar AF to BFF

NASA Image and Video Library

2017-08-30

The Exploration Mission-1 (EM-1) left-hand forward skirt for NASA's Space Launch System (SLS) solid rocket boosters arrives at the Booster Fabrication Facility (BFF) at NASA's Kennedy Space Center in Florida from Hangar AE at Cape Canaveral Air Force Station. In the BFF, the forward skirt will be inspected and prepared for use on the left-hand solid rocket booster for EM-1. NASA's Orion spacecraft will fly atop the SLS rocket on its first uncrewed flight test.
Orion EM-1 Forward Skirt Transport from Hangar AF to BFF

NASA Image and Video Library

2017-08-30

The Exploration Mission-1 (EM-1) left-hand forward skirt for NASA's Space Launch System (SLS) solid rocket boosters is transported by truck to the Booster Fabrication Facility (BFF) at NASA's Kennedy Space Center in Florida from Hangar AE at Cape Canaveral Air Force Station. In the BFF, the forward skirt will be inspected and prepared for use on the left-hand solid rocket booster for EM-1. NASA's Orion spacecraft will fly atop the SLS rocket on its first uncrewed flight test.
An adaptive density-based routing protocol for flying Ad Hoc networks

NASA Astrophysics Data System (ADS)

Zheng, Xueli; Qi, Qian; Wang, Qingwen; Li, Yongqiang

2017-10-01

An Adaptive Density-based Routing Protocol (ADRP) for Flying Ad Hoc Networks (FANETs) is proposed in this paper. The main objective is to calculate forwarding probability adaptively in order to increase the efficiency of forwarding in FANETs. ADRP dynamically fine-tunes the rebroadcasting probability of a node for routing request packets according to the number of neighbour nodes. Indeed, it is more interesting to privilege the retransmission by nodes with little neighbour nodes. We describe the protocol, implement it and evaluate its performance using NS-2 network simulator. Simulation results reveal that ADRP achieves better performance in terms of the packet delivery fraction, average end-to-end delay, normalized routing load, normalized MAC load and throughput, which is respectively compared with AODV.
KSC-98pc777

NASA Image and Video Library

1998-06-25

KENNEDY SPACE CENTER, FLA. -- A beach ball-sized infrared camera, part of the Forward Looking Infrared Radar (FLIR), has been mounted on the right siderail of NASA's Huey UH-1 helicopter. A KSC pilot prepares to fly the helicopter, which has also been outfitted with a portable global positioning satellite (GPS) system, to support Florida's Division of Forestry as they fight the brush fires which have been plaguing the state as a result of extremely dry conditions and lightning storms. The FLIR also includes a real-time television monitor and recorder installed inside the helicopter. While the FLIR collects temperature data and images, the GPS system provides the exact coordinates of the fires being observed and transmits the data to the firefighters on the ground. The Kennedy Space Center (KSC) security team routinely uses the FLIR equipment prior to Shuttle launch and landing activities to ensure that the area surrounding the launch pad and runway are clear of unauthorized personnel. KSC's Base Operations Contractor, EG&G Florida, operates the NASA-owned helicopter
SmallSat Innovations for Planetary Science

NASA Astrophysics Data System (ADS)

Weinberg, Jonathan; Petroy, Shelley; Roark, Shane; Schindhelm, Eric

2017-10-01

As NASA continues to look for ways to fly smaller planetary missions such as SIMPLEX, MoO, and Venus Bridge, it is important that spacecraft and instrument capabilities keep pace to allow these missions to move forward. As spacecraft become smaller, it is necessary to balance size with capability, reliability and payload capacity. Ball Aerospace offers extensive SmallSat capabilities matured over the past decade, utilizing our broad experience developing mission architecture, assembling spacecraft and instruments, and testing advanced enabling technologies. Ball SmallSats inherit their software capabilities from the flight proven Ball Configurable Platform (BCP) line of spacecraft, and may be tailored to meet the unique requirements of Planetary Science missions. We present here recent efforts in pioneering both instrument miniaturization and SmallSat/sensorcraft development through mission design and implementation. Ball has flown several missions with small, but capable spacecraft. We also have demonstrated a variety of enhanced spacecraft/instrument capabilities in the laboratory and in flight to advance autonomy in spaceflight hardware that can enable some small planetary missions.
Commander Brand and Pilot Overmyer operate controls on forward flight deck

NASA Technical Reports Server (NTRS)

1982-01-01

On forward flight deck, Commander Brand and Pilot Overmyer operate controls from commanders and pilots seats. Overall view taken from the aft flight deck looking forward shows Overmyer pointing to data on Panel 7 (F7) CRT 1 screen.
60. FORWARD AIRPLANE ELEVATOR PIT WITH ELEVATOR IN RAISED POSITION ...

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

60. FORWARD AIRPLANE ELEVATOR PIT WITH ELEVATOR IN RAISED POSITION AFT LOOKING FORWARD ON CENTERLINE SHOWING ELEVATOR GUIDES, WIREWAYS, SHEAVES, HYDRAULIC OIL TANKS AND ELEVATOR LANDING PADS. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
General view looking forward along the centerline of the Orbiter ...

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

General view looking forward along the centerline of the Orbiter Discovery looking into the payload bay. This view shows the external airlock and the beam-truss attach structure supporting it and attaching it to the payload bay sill longerons. Also note the protective covering over the docking mechanism on top of the airlock assembly. This external airlock configuration was for mating to the International Space Station. This photograph was taken in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Look Forward to Take a Hike Day This Spring | Poster

Cancer.gov

Are you looking forward to spring? Join Occupational Health Services (OHS) and the R&W Club Frederick for the next Take a Hike Day in April. At the fall event, about 30 employees walked or jogged the 1.3-mile course around the NCI at Frederick campus during their lunch hours. The event is designed to encourage employees to engage in physical activity, according to Sarah
Looking Forward to the Year 2000: Public Policy and Philanthropy. Working Papers, Spring Research Forum (San Francisco, California, March 17-18, 1988).

ERIC Educational Resources Information Center

Independent Sector, Washington, DC.

Forty-six working papers for presentation at a research forum on public policy and philanthropy are presented. Thirteen sections include the following topics: (1) looking forward to the year 2000: public policy and philanthropy (e.g. "Rationales for Tax Exemption," by Harvey P. Dale); (2) shifting boundaries among the sectors (e.g. "The Shifting…
Detail View looking at the protected structure and landing gear ...

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

Detail View looking at the protected structure and landing gear housing in the void created by the removal of the Forward Reaction Control System Module from the forward section of the Orbiter Discovery. This view was taken from the service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Generalized Wideband Harmonic Imaging of Nonlinearly Loaded Scatterers: Theory, Analysis, and Application for Forward-Looking Radar Target Detection

DTIC Science & Technology

2014-09-01

signal) operations; it is general enough so that it can accommodate high - power (large-signal) sensing as well—which may be needed to detect targets... Generalized Wideband Harmonic Imaging of Nonlinearly Loaded Scatterers: Theory, Analysis, and Application for Forward-Looking Radar Target...Research Laboratory Adelphi, MD 20783-1138 ARL-TR-7121 September 2014 Generalized Wideband Harmonic Imaging of Nonlinearly Loaded
Terrestrial Planet Finder Interferometer Science Working Group Report

NASA Technical Reports Server (NTRS)

Lawson, Peter R. (Editor); Lay, Oliver P. (Editor); Johnston, Kenneth J. (Editor); Beichman, Charles A. (Editor)

2007-01-01

Over the past two years, the focus of the project for the interferometric version of the Terrestrial Planet Finder(TPF-I) has been on the development of the scientific rational for the mission, the assessment of TPF-I architectures, the laboratory demonstration of key technologies, and the development of a detailed technology roadmap. The Science Working Group (SWG), in conjunction with European colleagues working on the European Space Agency's (ESA's) Darwin project, has reaffirmed the goals of TPF-I as part of a broad vision for the detection and characterization of Earth-like planets orbiting nearby stars and for the search for life on those planets. The SWG also helped to assess the performance of different interferometric configurations for TPF-I/Darwin. Building on earlier SWG reports, this document restates the scientific case for TPF-I, assesses suitable target stars and relevant wavelengths for observation, discusses dramatic new capabilities for general astrophysical observations, and summarizes how Spitzer has improved our knowledge of the incidence of zodiacal emission on the search for planets. This document discusses in some detail on laboratory advances in interferometric nulling and formation flying. Laboratory experiments have now achieved stable narrow- and broad-band nulling the levels of 10-6 and 2.0x10-5, respectively. A testbed has demonstrated formation flying using two realistic spacecraft mockups. With a suitably funded program of technology development, as summarized herein and described in more detail in the Technology Plan for the Terrestrial Planet Finder Interferometer (2005), the National Aeronautics and Space Administration (NASA) and ESA would be able to start within the coming decade a full-scale TPF-I/Darwin mission capable of finding Earths orbiting more than 150 nearby stars, or a scaled back interferometer capable of studying more than 30 stars. Finding evidence for life on just one of those planets would revolutionize our understanding of our place in the cosmos.

Research in millimeter wave techniques

NASA Technical Reports Server (NTRS)

Mcmillan, R. W.

1978-01-01

During the past six months, efforts on this project have been devoted to: (1) continuation of construction and testing of a 6 GHz subharmonic mixer model with extension of the pumping frequency of this mixer to omega sub s/4, (2) construction of a 183 GHz subharmonic mixer based on the results of tests on this 6 GHz model, (3) ground-based radiometric measurements at 183 GHz, (4) fabrication and testing of wire grid interferometers, (5) calculations of reflected and lost power in these interferometers, and (6) calculations of the antenna temperature due to water vapor to be expected in down-looking radiometry as a function of frequency. Significant events during the past six months include: (1) Receipt of a 183 GHz single-ended fundamental mixer, (2) attainment of 6 db single sideband conversion loss with the 6 GHz subharmonic mixer model by using a 1.5 GHz (omega sub s/4) pump frequency, (3) additional ground-based radiometric measurements and (4) derivation of equations for reflection and loss for wire grid interferometers.
Formation Flying: The Future of Remote Sensing from Space

NASA Technical Reports Server (NTRS)

Leitner, Jesse

2004-01-01

Over the next two decades a revolution is likely to occur in how remote sensing of Earth, other planets or bodies, and a range of phenomena in the universe is performed from space. In particular, current launch vehicle fairing volume and mass constraints will continue to restrict the size of monolithic telescope apertures which can be launched to little or no greater size than that of the Hubble Space Telescope, the largest aperture currently flying in space. Systems under formulation today, such as the James Webb Space Telescope will be able to increase aperture size and, hence, imaging resolution, by deploying segmented optics. However, this approach is limited as well, by our ability to control such segments to optical tolerances over long distances with highly uncertain structural dynamics connecting them. Consequently, for orders of magnitude improved resolution as required for imaging black holes, imaging planets, or performing asteroseismology, the only viable approach will be to fly a collection of spacecraft in formation to synthesize a virtual segmented telescope or interferometer with very large baselines. This paper provides some basic definitions in the area of formation flying, describes some of the strategic science missions planned in the National Aeronautics and Space Administration, and identifies some of the critical technologies needed to enable some of the most challenging space missions ever conceived which have realistic hopes of flying.
[Research on lateral shearing interferometer for field monitoring of natural gas pipeline leak].

PubMed

Zhang, Xue-Feng; Gao, Yu-Bin

2012-09-01

Aimed at the mechanical scanning spectroscopy equipment with poor anti-interference and anti-jamming ability, which affects the accuracy of its natural gas pipeline leak detection in the wild, a new type of lateral shearing interferometer system was designed. The system uses a beam splitter to get optical path difference by a mechanical scanning part, and it cancel the introduction of external vibration interference through the linkage between the two beam splitterw. The interference intensity of interference fringes produced was calculated, and analysis of a rotating beam splitter corresponds to the angle of the optical path difference function, solving for the maximum angle of the forward rotation and reverse rotation, which is the maximum optical path range. Experiments using the gas tank deflated simulated natural gas pipeline leak process, in the interference conditions, and the test data of the type WQF530 spectrometer and the new type of lateral shearing interferometer system were comparedt. The experimental results show that the relative error of both systems is about 1% in indoor conditions without interference. However, in interference environment, the error of WQF530 type spectrometer becomes larger, more than 10%, but the error of the new type of lateral shearing interferometer system is still below 5%. The detection accuracy of the type WQF530 spectrometer decreased significantly due to the environment. Therefore, the seismic design of the system can effectively offset power deviation and half-width increases of center wavelength caused by external interference, and compared to conventional mechanical scanning interferometer devices the new system is more suitable for field detection.
Closeup view looking forward along the centerline of the Orbiter ...

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

Close-up view looking forward along the centerline of the Orbiter Discovery looking into the payload bay. This view is a close-up view of the external airlock and the beam-truss attach structure supporting it and attaching it to the payload bay sill longerons. Also note the protective covering over the docking mechanism on top of the airlock assembly. This external airlock configuration was for mating to the International Space Station. This photograph was taken in the Orbiter Processing Facility at Kennedy Space Cente - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Simultaneous Water Vapor and Dry Air Optical Path Length Measurements and Compensation with the Large Binocular Telescope Interferometer

NASA Technical Reports Server (NTRS)

Defrere, D.; Hinz, P.; Downey, E.; Boehm, M.; Danchi, W. C.; Durney, O.; Ertel, S.; Hill, J. M.; Hoffmann, W. F.; Mennesson, B.;

2016-01-01

The Large Binocular Telescope Interferometer uses a near-infrared camera to measure the optical path length variations between the two AO-corrected apertures and provide high-angular resolution observations for all its science channels (1.5-13 microns). There is however a wavelength dependent component to the atmospheric turbulence, which can introduce optical path length errors when observing at a wavelength different from that of the fringe sensing camera. Water vapor in particular is highly dispersive and its effect must be taken into account for high-precision infrared interferometric observations as described previously for VLTI/MIDI or the Keck Interferometer Nuller. In this paper, we describe the new sensing approach that has been developed at the LBT to measure and monitor the optical path length fluctuations due to dry air and water vapor separately. After reviewing the current performance of the system for dry air seeing compensation, we present simultaneous H-, K-, and N-band observations that illustrate the feasibility of our feed forward approach to stabilize the path length fluctuations seen by the LBTI nuller uses a near-infrared camera to measure the optical path length variations between the two AO-corrected apertures and provide high-angular resolution observations for all its science channels (1.5-13 microns). There is however a wavelength dependent component to the atmospheric turbulence, which can introduce optical path length errors when observing at a wavelength different from that of the fringe sensing camera. Water vapor in particular is highly dispersive and its effect must be taken into account for high-precision infrared interferometric observations as described previously for VLTI MIDI or the Keck Interferometer Nuller. In this paper, we describe the new sensing approach that has been developed at the LBT to measure and monitor the optical path length fluctuations due to dry air and water vapor separately. After reviewing the current performance of the system for dry air seeing compensation, we present simultaneous H-, K-, and N-band observations that illustrate the feasibility of our feed forward approach to stabilize the path length fluctuations seen by the LBTI nuller.

Evaluating Perceived Probability of Threat-Relevant Outcomes and Temporal Orientation in Flying Phobia.

PubMed

Mavromoustakos, Elena; Clark, Gavin I; Rock, Adam J

2016-01-01

Probability bias regarding threat-relevant outcomes has been demonstrated across anxiety disorders but has not been investigated in flying phobia. Individual temporal orientation (time perspective) may be hypothesised to influence estimates of negative outcomes occurring. The present study investigated whether probability bias could be demonstrated in flying phobia and whether probability estimates of negative flying events was predicted by time perspective. Sixty flying phobic and fifty-five non-flying-phobic adults were recruited to complete an online questionnaire. Participants completed the Flight Anxiety Scale, Probability Scale (measuring perceived probability of flying-negative events, general-negative and general positive events) and the Past-Negative, Future and Present-Hedonistic subscales of the Zimbardo Time Perspective Inventory (variables argued to predict mental travel forward and backward in time). The flying phobic group estimated the probability of flying negative and general negative events occurring as significantly higher than non-flying phobics. Past-Negative scores (positively) and Present-Hedonistic scores (negatively) predicted probability estimates of flying negative events. The Future Orientation subscale did not significantly predict probability estimates. This study is the first to demonstrate probability bias for threat-relevant outcomes in flying phobia. Results suggest that time perspective may influence perceived probability of threat-relevant outcomes but the nature of this relationship remains to be determined.
Evaluating Perceived Probability of Threat-Relevant Outcomes and Temporal Orientation in Flying Phobia

PubMed Central

Mavromoustakos, Elena; Clark, Gavin I.; Rock, Adam J.

2016-01-01

Probability bias regarding threat-relevant outcomes has been demonstrated across anxiety disorders but has not been investigated in flying phobia. Individual temporal orientation (time perspective) may be hypothesised to influence estimates of negative outcomes occurring. The present study investigated whether probability bias could be demonstrated in flying phobia and whether probability estimates of negative flying events was predicted by time perspective. Sixty flying phobic and fifty-five non-flying-phobic adults were recruited to complete an online questionnaire. Participants completed the Flight Anxiety Scale, Probability Scale (measuring perceived probability of flying-negative events, general-negative and general positive events) and the Past-Negative, Future and Present-Hedonistic subscales of the Zimbardo Time Perspective Inventory (variables argued to predict mental travel forward and backward in time). The flying phobic group estimated the probability of flying negative and general negative events occurring as significantly higher than non-flying phobics. Past-Negative scores (positively) and Present-Hedonistic scores (negatively) predicted probability estimates of flying negative events. The Future Orientation subscale did not significantly predict probability estimates. This study is the first to demonstrate probability bias for threat-relevant outcomes in flying phobia. Results suggest that time perspective may influence perceived probability of threat-relevant outcomes but the nature of this relationship remains to be determined. PMID:27557054
Vision Hampton Roads : strategy committee minutes & attendance.

DOT National Transportation Integrated Search

2010-02-22

February 20, 2009 : HRP Executive Committee Meeting, Looking Back, Looking Forward : March 20, 2009 : HRP Board Meeting, Accolades & Action, Doing Things Jointly with Comprehensive : Economic Development Strategies : April 17,...
Modes of thrust generation in flying animals

NASA Astrophysics Data System (ADS)

Luo, Haoxiang; Song, Jialei; Tobalske, Bret; Luo Team; Tobalske Team

2016-11-01

For flying animals in forward flight, thrust is usually much smaller as compared with weight support and has not been given the same amount of attention. Several modes of thrust generation are discussed in this presentation. For insects performing slow flight that is characterized by low advance ratios (i.e., the ratio between flight speed and wing speed), thrust is usually generated by a "backward flick" mode, in which the wings moves upward and backward at a faster speed than the flight speed. Paddling mode is another mode used by some insects like fruit flies who row their wings backward during upstroke like paddles (Ristroph et al., PRL, 2011). Birds wings have high advance ratios and produce thrust during downstroke by directing aerodynamic lift forward. At intermediate advance ratios around one (e.g., hummingbirds and bats), the animal wings generate thrust during both downstroke and upstroke, and thrust generation during upstroke may come at cost of negative weight support. These conclusions are supported by previous experiment studies of insects, birds, and bats, as well as our recent computational modeling of hummingbirds. Supported by the NSF.
Down-Looking Interferometer Study II, Volume I,

DTIC Science & Technology

1980-03-01

g(standard deviation of AN )(standard deviation of(3) where T’rm is the "reference spectrum", an estimate of the actual spectrum v gv T ’V Cgv . If jpj...spectrum T V . cgv . According to Eq. (2), Z is the standard deviation of the observed contrast spectral radiance AN divided by the effective rms system
Multiple Kernel Learning for Explosive Hazard Detection in Forward-Looking Ground-Penetrating Radar

DTIC Science & Technology

2012-04-01

Kevin Stone, Derek T. Anderson, James M. Keller, Dominic K.C. Ho, Tuan T. Ton, David C. Wong , Mehrdad Soumekh University of Missouri - Columbia...James M. Kellera, K.C. Hoa, Tuan T. Tone, David C. Wong\\ and Mehrdad Soumekhd aDept. ofElectrical and Computer Engineering, University of Missouri...2] Cremer , F., Schavemaker, J.G., de Jong, W., and Schutte, K., "Comparison of vehicle-mounted forward-looking polarimetric infrared and downward
26. Port side of engine room looking forward from aft ...

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

26. Port side of engine room looking forward from aft bulkhead. This area contains mostly electrical equipment. Two single-cylinder steam-driven dynamos are located near the engine bed, one at right foreground, the other in background. At left in image are a motor-generator set installed to convert DC current (from dynamos) to AC current. Edge-on view of control panel appears near center of image. - Ferry TICONDEROGA, Route 7, Shelburne, Chittenden County, VT
Implications of Fail-Forward in an Online Environment under Alternative Grading Schemes

ERIC Educational Resources Information Center

Patron, Hilde; Smith, William J.

2011-01-01

The concept of fail-forward can be used as a teaching technique to motivate students to learn from their mistakes. For example, when students are allowed to re-work incorrect responses on a test for a partial grade they are failing-forward. In this paper we look at the effects of failing-forward on student effort in online learning environments.…
SPECS: the kilometer-baseline far-IR interferometer in NASA's space science roadmap

NASA Astrophysics Data System (ADS)

Leisawitz, David T.; Abel, Tom; Allen, Ronald J.; Benford, Dominic J.; Blain, Andrew; Bombardelli, Claudio; Calzetti, Daniela; DiPirro, Michael J.; Ehrenfreund, Pascale; Evans, Neal J., II; Fischer, Jacqueline; Harwit, Martin; Hyde, Tristram T.; Kuchner, Marc J.; Leitner, Jesse A.; Lorenzini, Enrico C.; Mather, John C.; Menten, Karl M.; Moseley, Samuel H., Jr.; Mundy, Lee G.; Nakagawa, Takao; Neufeld, David A.; Pearson, John C.; Rinehart, Stephen A.; Roman, Juan; Satyapal, Shobita; Silverberg, Robert F.; Stahl, H. Philip; Swain, Mark R.; Swanson, Theodore D.; Traub, Wesley A.; Wright, Edward L.; Yorke, Harold W.

2004-10-01

Ultimately, after the Single Aperture Far-IR (SAFIR) telescope, astrophysicists will need a far-IR observatory that provides angular resolution comparable to that of the Hubble Space Telescope. At such resolution galaxies at high redshift, protostars, and nascent planetary systems will be resolved, and theoretical models for galaxy, star, and planet formation and evolution can be subjected to important observational tests. This paper updates information provided in a 2000 SPIE paper on the scientific motivation and design concepts for interferometric missions SPIRIT (the Space Infrared Interferometric Telescope) and SPECS (the Submillimeter Probe of the Evolution of Cosmic Structure). SPECS is a kilometer baseline far-IR/submillimeter imaging and spectral interferometer that depends on formation flying, and SPIRIT is a highly-capable pathfinder interferometer on a boom with a maximum baseline in the 30 - 50 m range. We describe recent community planning activities, remind readers of the scientific rationale for space-based far-infrared imaging interferometry, present updated design concepts for the SPIRIT and SPECS missions, and describe the main issues currently under study. The engineering and technology requirements for SPIRIT and SPECS, additional design details, recent technology developments, and technology roadmaps are given in a companion paper in the Proceedings of the conference on New Frontiers in Stellar Interferometry.
Preliminary optical design of the coronagraph for the ASPIICS formation flying mission

NASA Astrophysics Data System (ADS)

Vivès, S.; Lamy, P.; Saisse, M.; Boit, J.-L.; Koutchmy, S.

2017-11-01

Formation flyers open new perspectives and allow to conceive giant, externally-occulted coronagraphs using a two-component space system with the external occulter on one spacecraft and the optical instrument on the other spacecraft at approximately 100-150 m from the first one. ASPIICS (Association de Satellites Pour l'Imagerie et l'Interfromtrie de la Couronne Solaire) is a mission proposed to ESA in the framework of the PROBA-3 program of formation flying which is presently in phase A to exploit this technique for coronal observations. ASPIICS is composed of a single coronagraph which performs high spatial resolution imaging of the corona as well as 2-dimensional spectroscopy of several emission lines from the coronal base out to 3 R. The selected lines allow to address different coronal regions: the forbidden line of Fe XIV at 530.285 nm (coronal matter), Fe IX/X at 637.4 nm (coronal holes), HeI at 587.6 nm (cold matter). An additional broad spectral channel will image the white light corona so as to derive electron densities. The classical design of an externally occulted coronagraph is adapted to the detection of the very inner corona as close as 1.01 R and the addition of a Fabry-Perot interferometer using a so-called "etalon". This paper is dedicated to the description of the optical design and its critical components: the entrance optics and the FabryPerot interferometer.
Turbulence Measurements by Interferometry and Far-forward Scattering on the HSX Stellarator

NASA Astrophysics Data System (ADS)

Deng, C. B.; Brower, D. L.; Anderson, D. T.; Anderson, F. S. B.; Likin, K. M.; Talmadge, J. N.

2017-10-01

After neo-classical transport was reduced by restoring symmetry along the helical axis, a primary physics goal for HSX is to study how 3-D shaping can reduce turbulence thereby requiring measurement of turbulence with kyρs up to 1. For characteristic HSX parameters (Te 200 eV at r/a 0.5 where the density gradient peaks), this condition corresponds to ky up to 7 cm-1. To accommodate this goal, a new 9-chord HSX interferometer/far-forward scattering system has been designed to measure density turbulence at higher k. The new system employing two high-power (30 mW each, 320 GHz), solid-state sources with frequency offset up to 6 MHz. This will permit true heterodyne detection, thereby realizing faster measurement time response, increased bandwidth and reduced noise. High power sources and high sensitivity planar-diode mixers will allow us to reduce the aperture of the receiver optics to a few mm thereby increasing the maximum wavenumber to k 15 cm-1. Reconfiguring the interferometer system into a finite-angle collective scattering arrangement is also planned as it will increase the measured k-spectrum up to 18 cm-1 with some spatial resolution (core or edge). Supported by USDOE Grants DE-FG03-01ER54615 and DE-FG02-93ER54222.
ARC-2013-ACD13-0044-002

NASA Image and Video Library

2013-03-12

Women Fly it forward event at Hiller Aviation. Aisha Bowe (right) with Ames Navigation, Guidance & Control Systems Branch reaches out to Julia Smith (left) and Taylor Grafstrom (center) about women in aviation.
LIGO and the opening of a unique observational window on the universe.

PubMed

Kalogera, Vassiliki; Lazzarini, Albert

2017-03-21

A unique window on the universe opened on September 14, 2015, with direct detection of gravitational waves by the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors. This event culminated a half-century effort around the globe to develop terrestrial detectors of adequate sensitivity to achieve this goal. It also happened appropriately only a few months before the centennial of Einstein's final paper introducing the general theory of relativity. This detection provided the surprising discovery of a coalescing pair of "heavy" black holes (more massive than [Formula: see text] M[Formula: see text]) leading to the formation of a spinning [Formula: see text]62 solar mass black hole. One more binary black-hole detection and a significant candidate event demonstrated that a population of such merging binaries is formed in nature with a broad mass spectrum. This unique observational sample has already provided concrete measurements on the coalescence rates and has allowed us to test the theory of general relativity in the strong-field regime. As this nascent field of gravitational-wave astrophysics is emerging we are looking forward to the detection of binary mergers involving neutron stars and their electromagnetic counterparts, as well as continuous-wave sources, supernovae, a stochastic confusion background of compact-object mergers, known sources detected in unexpected ways, and completely unknown sources.
LIGO and the opening of a unique observational window on the universe

PubMed Central

Kalogera, Vassiliki; Lazzarini, Albert

2017-01-01

A unique window on the universe opened on September 14, 2015, with direct detection of gravitational waves by the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors. This event culminated a half-century effort around the globe to develop terrestrial detectors of adequate sensitivity to achieve this goal. It also happened appropriately only a few months before the centennial of Einstein’s final paper introducing the general theory of relativity. This detection provided the surprising discovery of a coalescing pair of “heavy” black holes (more massive than ≃25 M๏) leading to the formation of a spinning ≃62 solar mass black hole. One more binary black-hole detection and a significant candidate event demonstrated that a population of such merging binaries is formed in nature with a broad mass spectrum. This unique observational sample has already provided concrete measurements on the coalescence rates and has allowed us to test the theory of general relativity in the strong-field regime. As this nascent field of gravitational-wave astrophysics is emerging we are looking forward to the detection of binary mergers involving neutron stars and their electromagnetic counterparts, as well as continuous-wave sources, supernovae, a stochastic confusion background of compact-object mergers, known sources detected in unexpected ways, and completely unknown sources. PMID:28283663
Steering a virtual blowfly: simulation of visual pursuit.

PubMed

Boeddeker, Norbert; Egelhaaf, Martin

2003-09-22

The behavioural repertoire of male flies includes visually guided chasing after moving targets. The visuomotor control system for these pursuits belongs to the fastest found in the animal kingdom. We simulated a virtual fly, to test whether or not experimentally established hypotheses on the underlying control system are sufficient to explain chasing behaviour. Two operating instructions for steering the chasing virtual fly were derived from behavioural experiments: (i) the retinal size of the target controls the fly's forward speed and, thus, indirectly its distance to the target; and (ii) a smooth pursuit system uses the retinal position of the target to regulate the fly's flight direction. Low-pass filters implement neuronal processing time. Treating the virtual fly as a point mass, its kinematics are modelled in consideration of the effects of translatory inertia and air friction. Despite its simplicity, the model shows behaviour similar to that of real flies. Depending on its starting position and orientation as well as on target size and speed, the virtual fly either catches the target or follows it indefinitely without capture. These two behavioural modes of the virtual fly emerge from the control system for flight steering without implementation of an explicit decision maker.

Baby's Head Shape: What's Normal?

MedlinePlus

... out. This is known as positional plagiocephaly. Positional molding might be most noticeable when you're looking ... the flat side might look pushed forward. Positional molding is generally considered a cosmetic issue. Flat spots ...
Practical Classroom Applications of Language Experience: Looking Back, Looking Forward.

ERIC Educational Resources Information Center

Nelson, Olga G., Ed.; Linek, Wayne M., Ed.

The 38 essays in this book look back at language experience as an educational approach, provide practical classroom applications, and reconceptualize language experience as an overarching education process. Classroom teachers and reading specialists describe strategies in use in a variety of classroom settings and describe ways to integrate…
Pathfinder-Plus aircraft in flight

NASA Technical Reports Server (NTRS)

1998-01-01

The Pathfinder-Plus solar-powered aircraft is shown taking off from a runway, then flying at low altitude over the ocean. The vehicle, which looks like a flying ruler, operates at low airspeed. Among the missions proposed for a solar-powered aircraft are communications relay, atmospheric studies, pipeline monitoring and gas leak detection, environmental monitoring using thermal and radar images, and disaster relief and monitoring.
System matrix computation vs storage on GPU: A comparative study in cone beam CT.

PubMed

Matenine, Dmitri; Côté, Geoffroi; Mascolo-Fortin, Julia; Goussard, Yves; Després, Philippe

2018-02-01

Iterative reconstruction algorithms in computed tomography (CT) require a fast method for computing the intersection distances between the trajectories of photons and the object, also called ray tracing or system matrix computation. This work focused on the thin-ray model is aimed at comparing different system matrix handling strategies using graphical processing units (GPUs). In this work, the system matrix is modeled by thin rays intersecting a regular grid of box-shaped voxels, known to be an accurate representation of the forward projection operator in CT. However, an uncompressed system matrix exceeds the random access memory (RAM) capacities of typical computers by one order of magnitude or more. Considering the RAM limitations of GPU hardware, several system matrix handling methods were compared: full storage of a compressed system matrix, on-the-fly computation of its coefficients, and partial storage of the system matrix with partial on-the-fly computation. These methods were tested on geometries mimicking a cone beam CT (CBCT) acquisition of a human head. Execution times of three routines of interest were compared: forward projection, backprojection, and ordered-subsets convex (OSC) iteration. A fully stored system matrix yielded the shortest backprojection and OSC iteration times, with a 1.52× acceleration for OSC when compared to the on-the-fly approach. Nevertheless, the maximum problem size was bound by the available GPU RAM and geometrical symmetries. On-the-fly coefficient computation did not require symmetries and was shown to be the fastest for forward projection. It also offered reasonable execution times of about 176.4 ms per view per OSC iteration for a detector of 512 × 448 pixels and a volume of 384 3 voxels, using commodity GPU hardware. Partial system matrix storage has shown a performance similar to the on-the-fly approach, while still relying on symmetries. Partial system matrix storage was shown to yield the lowest relative performance. On-the-fly ray tracing was shown to be the most flexible method, yielding reasonable execution times. A fully stored system matrix allowed for the lowest backprojection and OSC iteration times and may be of interest for certain performance-oriented applications. © 2017 American Association of Physicists in Medicine.
Simple Fourier optics formalism for high-angular-resolution systems and nulling interferometry.

PubMed

Hénault, François

2010-03-01

Reviewed are various designs of advanced, multiaperture optical systems dedicated to high-angular-resolution imaging or to the detection of exoplanets by nulling interferometry. A simple Fourier optics formalism applicable to both imaging arrays and nulling interferometers is presented, allowing their basic theoretical relationships to be derived as convolution or cross-correlation products suitable for fast and accurate computation. Several unusual designs, such as a "superresolving telescope" utilizing a mosaicking observation procedure or a free-flying, axially recombined interferometer are examined, and their performance in terms of imaging and nulling capacity are assessed. In all considered cases, it is found that the limiting parameter is the diameter of the individual telescopes. A final section devoted to nulling interferometry shows an apparent superiority of axial versus multiaxial recombining schemes. The entire study is valid only in the framework of first-order geometrical optics and scalar diffraction theory. Furthermore, it is assumed that all entrance subapertures are optically conjugated with their associated exit pupils.
The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII): Spatially Resolved Spectroscopy in the Far-Infrared

NASA Technical Reports Server (NTRS)

Rinehart, Stephen

2009-01-01

Astronomical studies at infrared wavelengths have dramatically improved our understanding of the universe, and observations with Spitzer, the upcoming Herschel mission, and SOFIA will continue to provide exciting new discoveries. The relatively low angular resolution of these missions, however, is insufficient to resolve the physical scale on which mid-to far-infrared emission arises, resulting in source and structure ambiguities that limit our ability to answer key science questions. Interferometry enables high angular resolution at these wavelengths - a powerful tool for scientific discovery. We will build the Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII), an eight-meter baseline Michelson stellar interferometer to fly on a high-altitude balloon. BETTII's spectral-spatial capability, provided by an instrument using double-Fourier techniques, will address key questions about the nature of disks in young star clusters and active galactic nuclei and the envelopes of evolved stars. BETTII will also lay the technological groundwork for future space interferometers and for suborbital programs optimized for studying extrasolar planets.
A Sparse Bayesian Approach for Forward-Looking Superresolution Radar Imaging

PubMed Central

Zhang, Yin; Zhang, Yongchao; Huang, Yulin; Yang, Jianyu

2017-01-01

This paper presents a sparse superresolution approach for high cross-range resolution imaging of forward-looking scanning radar based on the Bayesian criterion. First, a novel forward-looking signal model is established as the product of the measurement matrix and the cross-range target distribution, which is more accurate than the conventional convolution model. Then, based on the Bayesian criterion, the widely-used sparse regularization is considered as the penalty term to recover the target distribution. The derivation of the cost function is described, and finally, an iterative expression for minimizing this function is presented. Alternatively, this paper discusses how to estimate the single parameter of Gaussian noise. With the advantage of a more accurate model, the proposed sparse Bayesian approach enjoys a lower model error. Meanwhile, when compared with the conventional superresolution methods, the proposed approach shows high cross-range resolution and small location error. The superresolution results for the simulated point target, scene data, and real measured data are presented to demonstrate the superior performance of the proposed approach. PMID:28604583
Study of unsteady flow field over a forward-looking endoatmospheric hit-to-kill interceptor

NASA Technical Reports Server (NTRS)

Yang, H. Q.; Antonison, Mark

1993-01-01

Forward-looking recessed aperture interceptor has significant aero-optical and aero-thermal advantages. Previous experimental studies have shown that the flow field in front of a forward-looking cavity is unsteady and the bow shock oscillates at the cavity fundamental resonant frequency. In this study, an advanced CFD code is applied to study the above unsteady phenomena. The code is first validated against the experiments and good comparisons are found. The numerical parametric study shows that the existence of oscillatory bow shock is very sensitive to the cavity geometry. At a FOV of 60 deg, the initial transient quickly dampens out to a steady state. With a decrease of FOV, an unsteady oscillatory flow field is sustained after initial transient and the amplitude of oscillation is a function of FOV. For FOV of 20 deg, the amplitude of pressure oscillation is 25 percent of the mean value in the cavity. For a FOV of 10 deg, it can be as high as 50 percent.
Astronaut Alan Bean flies the Astronaut Maneuvering Equipment

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment in the forward dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. Bean is strapped in to the back-mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). This ASMU exerperiment is being done in shirt sleeves. The dome area where the experiment is conducted is about 22 feet in diameter and 19 feet from top to bottom.
NASA is with you when you fly on This Week @NASA - November 21, 2014NASA invited social media members Nov. 18 and 19 to the agency’s Armstrong Flight Research Center for a two-day event highlighting the ways NASA is with you when you fly. The NASA social gave participants an exclusive look at the latest tools and technologies being developed to improve the efficiency, safety and adaptability of air transportation. Also, Next ISS crew trains, 3D printer installed in space, Asteroid capture technology test, Journey to Mars media day and more!

NASA Image and Video Library

2014-11-21

NASA invited social media members Nov. 18 and 19 to the agency’s Armstrong Flight Research Center for a two-day event highlighting the ways NASA is with you when you fly. The NASA social gave participants an exclusive look at the latest tools and technologies being developed to improve the efficiency, safety and adaptability of air transportation. Also, Next ISS crew trains, 3D printer installed in space, Asteroid capture technology test, Journey to Mars media day and more!
Towards a laboratory breadboard for PEGASE, the DARWIN pathfinder

NASA Astrophysics Data System (ADS)

Cassaing, F.; Le Duigou, J.-M.; Sorrente, B.; Fleury, B.; Gorius, N.; Brachet, F.; Buisset, C.; Ollivier, M.; Hénault, F.; Mourard, D.; Rabbia, Y.; Delpech, M.; Guidotti, P.-Y.; Léger, A.; Barillot, M.; Rouan, D.; Rousset, G.

2017-11-01

PEGASE, a spaceborne mission proposed to the CNES, is a 2-aperture interferometer for nulling and interferometric imaging. PEGASE is composed of 3 free-flying satellites (2 siderostats and 1 beam combiner) with baselines from 50 to 500 m. The goals of PEGASE are the spectroscopy of hot Jupiter (Pegasides) and brown dwarves, the exploration of the inner part of protoplanetary disks and the validation in real space conditions of nulling and visibility interferometry with formation flying. During a phase-0 study performed in 2005 at CNES, ONERA and in the laboratories, the critical subsystems of the optical payload have been investigated and a preliminary system integration has been performed. These subsystems are mostly the broadband (2.5-5 μm) nuller and the cophasing system (visible) dedicated to the real-time control of the OPD/tip/tilt inside the payload. A laboratory breadboard of the payload is under definition and should be built in 2007.
Paddling Mode of Forward Flight in Insects

NASA Astrophysics Data System (ADS)

Ristroph, Leif; Bergou, Attila J.; Guckenheimer, John; Wang, Z. Jane; Cohen, Itai

2011-04-01

By analyzing high-speed video of the fruit fly, we discover a swimminglike mode of forward flight characterized by paddling wing motions. We develop a new aerodynamic analysis procedure to show that these insects generate drag-based thrust by slicing their wings forward at low angle of attack and pushing backwards at a higher angle. Reduced-order models and simulations reveal that the law for flight speed is determined by these wing motions but is insensitive to material properties of the fluid. Thus, paddling is as effective in air as in water and represents a common strategy for propulsion through aquatic and aerial environments.
Magdalena Ridge Observatory Interferometer - New Path to First Light

NASA Astrophysics Data System (ADS)

Creech-Eakman, Michelle J.; Payne, Ifan; Haniff, Chris; Buscher, David; Young, John; Romero, Van; Magdalena Ridge Observatory Interferometer Team

2016-01-01

The Magdalena Ridge Observatory Interferometer (MROI), a 10-telescope optical/near-IR interferometer with baselines ranging from 7.8 to 343 meters, has been conceived to be the most ambitious optical/NIR interferometric array under construction to date. U.S. Congressional, N.M. State and university funding (from NM Tech and partner funding at the University of Cambridge) attained from 2000-13 provided for a nearly complete system design, installation of a large portion of the physical infrastructure at the Magdalena Ridge, the first telescope, delay line, fringe tracker and many other necessary sub-systems. New funding has recently been obtained under a cooperative agreement between NM Tech and the Air Force Research Lab (AFRL) to bring the facility to three fully operational telescopes and associated hardware such that first fringes and closure phase will be realized within 5 years. The completed facility will be able to provide support for observing geosynchronous satellites as well as many exciting observations of astronomical targets. An update on the MROI status, plans moving forward for the next 5 years, and some examples of observational applications feasible at different phases of the array's completion will be presented.
Reply to "Comment on `Particle path through a nested Mach-Zehnder interferometer' "

NASA Astrophysics Data System (ADS)

Griffiths, Robert B.

2018-02-01

While much of the technical analysis in the preceding Comment is correct, in the end it confirms the conclusion reached in my previous work [Phys. Rev. A 94, 032115 (2016), 10.1103/PhysRevA.94.032115]: A consistent histories analysis provides no support for the claim of counterfactual quantum communication put forward by Salih et al. [Phys. Rev. Lett. 110, 170502 (2013), 10.1103/PhysRevLett.110.170502].
Looking back and Looking Forward: 25 Years of Adult Education.

ERIC Educational Resources Information Center

Stock, Arthur

1992-01-01

Adult education should move away from an increasingly pragmatic and vocational focus toward a global view of sustainable development and social change that addresses the imbalances in the wealth of nations. (SK)
Multilingual Asia: Looking Back, Looking across, Looking Forward

ERIC Educational Resources Information Center

Bruthiaux, Paul

2009-01-01

In any discussion of multilingual Asia, caution is in order, for two reasons. One is that Asia is a vast land mass connecting variegated peoples cartographically but not sociologically. Second, describing and accounting for the sociolinguistic complexities of Asia (or anywhere else, for that matter) is history in the making in that, just like…
Looking Back, Looking Forward

ERIC Educational Resources Information Center

Nash, Gary B.

2009-01-01

In this article, the author looks back at the time Charlotte Crabtree, longtime Professor of Education at UCLA with a special interest in elementary history-social studies curriculum, asked him to join her in applying for a million dollar grant to be awarded by the National Endowment for the Humanities (NEH), chaired by Lynne Cheney. Crabtree had…
Design and optimal control of on-orbit servicing trajectory for target vehicle in non-coplanar elliptical orbit

NASA Astrophysics Data System (ADS)

Zhou, Wenyong; Yuan, Jianping; Luo, Jianjun

2005-11-01

Autonomous on-orbit servicing provides flexibility to space systems and has great value both in civil and in military. When a satellite performs on-orbit servicing tasks, flying around is the basic type of motion. This paper is concerned with the design and control problems of a chaser satellite flying around a target spacecraft in non-coplanar elliptical orbit for a long time. At first, a mathematical model used to design a long-term flying around trajectory is presented, which is applicable to the situation that the target spacecraft flies in an elliptical orbit. The conditions of the target at the centre of the flying around path are deduced. Considering the safety and task requirements, a long-term flying around trajectory is designed. Taking into account perturbations and navigation errors which can cause the trajectory unstable and mission impossible, a two-impulse control method is put forward. Genetic algorithm is used to minimize the cost function which considers fuel consumption and bias simultaneously. Some simulation works are carried out and the results indicate the flying around mathematical model and the trajectory control method can be used in the design and control of a long-term flying around trajectory.
KSC-98pc780

NASA Image and Video Library

1998-06-25

KENNEDY SPACE CENTER, FLA. -- Sgt. Mark Hines, of Kennedy Space Center (KSC) Security, points out a view of a fire on the Forward Looking Infrared Radar (FLIR) video screen to Greg Dunn, of Florida's Division of Forestry, as KSC pilots fly NASA's Huey UH-1 helicopter over fires burning in Volusia County, Florida. The FLIR includes a beach-ball sized infrared camera that is mounted on the helicopter's right siderail and a real-time TV monitor and recorder installed inside. The helicopter has also been outfitted with a portable global positioning satellite (GPS) system to support the Division of Forestry as they fight the brush fires which have been plaguing the state as a result of extremely dry conditions and lightning storms. While the FLIR collects temperature data and images, the GPS system provides the exact coordinates of the fires being observed and transmits the data to the firefighters on the ground. KSC's security team routinely uses the FLIR equipment prior to Shuttle launch and landing activities to ensure that the area surrounding the launch pad and runway are clear of unauthorized personnel. KSC's Base Operations Contractor, EG&G Florida, operates the NASA-owned helicopter.
KSC-98pc1141

NASA Image and Video Library

1998-09-22

Viewed looking forward, this Spacelab module is empty now, being prepared in the Operations & Checkout Building for shipment to the National Air and Space Museum in Washington, DC. Visible on the floor are the foot restraints used by astronauts to keep them stationary while conducting experiments. Spacelab was designed by the European Space Agency (ESA) for the Space Shuttle program. It first flew on STS-9 in November 1983 and its final flight was the STS-90 Neurolab mission in April 1998. The Spacelab concept of modular experiment racks in a pressurized shirt-sleeve environment made it highly user-friendly and accessible. Numerous experiments conceived by hundreds of scientists on the ground were conducted by flight crews in orbit. Spacelab modules served as on-orbit homes for everything from squirrel monkeys to plant seeds. They supported astronomical as well as Earth observations, for servicing the Hubble Space Telescope and for research preparatory to the International Space Station. One of the greatest benefits afforded by the Spacelab missions was the opportunity to fly a mission more than once, with the second or third flight building on the experiences and data gathered from its predecessors

KSC-07pd3134

NASA Image and Video Library

2007-11-04

KENNEDY SPACE CENTER, FLA. -- One of the U.S. Navy F-18 Super Hornets flies over NASA's Kennedy Space Center as part of the World Space Expo aerial salute. Other aircraft joining in the expo salute include the U.S. Air Force Thunderbirds Demonstration Squadron, U.S. Air Force F-22 Raptor, U.S. Air Force F-15 Eagle, P-51 Mustang Heritage Flight, and the U.S. Air Force 920th Rescue Wing, which was responsible for Mercury and Gemini capsule recovery, and the U.S. Army Golden Knights precision skydiving team. The World Space Expo held Nov. 1-4 was an event commemorating humanity's first 50 years in space while looking forward to returning people to the moon and exploring beyond. The expo showcased various panels, presentations and educational programs. It also was a part of NASA's 50th anniversary celebrations, highlighting the 45th Anniversary of the Mercury Program celebration featuring original NASA astronauts John Glenn and Scott Carpenter and the Pioneering Women of Aerospace forum featuring Eileen Collins and other prominent female space veterans. The agency was founded Oct. 1, 1958. Photo credit: NASA/Kim Shiflett
KSC-07pd3122

NASA Image and Video Library

2007-11-04

KENNEDY SPACE CENTER, FLA. -- At NASA's Kennedy Space Center, the U.S. Navy F-18 Super Hornets demonstrate their formation flying during the World Space Expo aerial salute. Other aircraft joining in the expo salute include the U.S. Air Force Thunderbirds Demonstration Squadron, U.S. Air Force F-22 Raptor, U.S. Air Force F-15 Eagle, P-51 Mustang Heritage Flight, U.S. Air Force 920th Rescue wing, which was responsible for Mercury and Gemini capsule recovery, and the U.S. Army Golden Knights demonstrating precision skydiving. The World Space Expo held Nov. 1-4 was an event commemorating humanity's first 50 years in space while looking forward to returning people to the moon and exploring beyond. The expo showcased various panels, presentations and educational programs. It also was a part of NASA's 50th anniversary celebrations, highlighting the 45th Anniversary of the Mercury Program celebration featuring original NASA astronauts John Glenn and Scott Carpenter and the Pioneering Women of Aerospace forum featuring Eileen Collins and other prominent female space veterans. The agency was founded Oct. 1, 1958. Photo credit: NASA/Chris Chamberland
KSC-07pd3117

NASA Image and Video Library

2007-11-04

KENNEDY SPACE CENTER, FLA. -- At NASA's Kennedy Space Center, a U.S. Air Force F-22 Raptor flies overhead as part of the World Space Expo aerial salute. Other aircraft joining in the expo salute include the U.S. Air Force Thunderbirds Demonstration Squadron, the U.S. Navy F-18 Super Hornets, U.S. Air Force F-15 Eagle, P-51 Mustang Heritage Flight, the U.S. Air Force 920th Rescue wing, which was responsible for Mercury and Gemini capsule recovery, and the U.S. Army Golden Knights demonstrating precision skydiving. The World Space Expo held Nov. 1-4 was an event commemorating humanity's first 50 years in space while looking forward to returning people to the moon and exploring beyond. The expo showcased various panels, presentations and educational programs. It also was a part of NASA's 50th anniversary celebrations, highlighting the 45th Anniversary of the Mercury Program celebration featuring original NASA astronauts John Glenn and Scott Carpenter and the Pioneering Women of Aerospace forum featuring Eileen Collins and other prominent female space veterans. The agency was founded Oct. 1, 1958. Photo credit: NASA/Chris Chamberland
KSC-07pd3138

NASA Image and Video Library

2007-11-04

KENNEDY SPACE CENTER, FLA. -- The U.S. Air Force Thunderbirds Demonstration Squadron fly in close formation during the World Space Expo aerial salute. Other aircraft joining in the expo salute include the U.S. Navy F-18 Super Hornets, U.S. Air Force F-22 Raptor, U.S. Air Force F-15 Eagle, P-51 Mustang Heritage Flight, the U.S. Air Force 920th Rescue Wing, which was responsible for Mercury and Gemini capsule recovery, and the U.S. Army Golden Knights precision skydivers. The World Space Expo held Nov. 1-4 was an event commemorating humanity's first 50 years in space while looking forward to returning people to the moon and exploring beyond. The expo showcased various panels, presentations and educational programs. It also was a part of NASA's 50th anniversary celebrations, highlighting the 45th Anniversary of the Mercury Program celebration featuring original NASA astronauts John Glenn and Scott Carpenter and the Pioneering Women of Aerospace forum featuring Eileen Collins and other prominent female space veterans. The agency was founded Oct. 1, 1958. Photo credit: NASA/Kim Shiflett
KSC-07pd3135

NASA Image and Video Library

2007-11-04

KENNEDY SPACE CENTER, FLA. -- The U.S. Air Force Thunderbirds Demonstration Squadron flies in formation over NASA's Kennedy Space Center as part of the World Space Expo aerial salute. Other aircraft joining in the expo salute include the U.S. Navy F-18 Super Hornets, U.S. Air Force F-22 Raptor, U.S. Air Force F-15 Eagle, P-51 Mustang Heritage Flight, and the U.S. Air Force 920th Rescue Wing, which was responsible for Mercury and Gemini capsule recovery, and the U.S. Army Golden Knights precision skydiving team. The World Space Expo held Nov. 1-4 was an event commemorating humanity's first 50 years in space while looking forward to returning people to the moon and exploring beyond. The expo showcased various panels, presentations and educational programs. It also was a part of NASA's 50th anniversary celebrations, highlighting the 45th Anniversary of the Mercury Program celebration featuring original NASA astronauts John Glenn and Scott Carpenter and the Pioneering Women of Aerospace forum featuring Eileen Collins and other prominent female space veterans. The agency was founded Oct. 1, 1958. Photo credit: NASA/Kim Shiflett
Looking back: forward looking

PubMed Central

2017-01-01

Abstract GigaScience is now 5 years old, having been launched at the 2012 Intelligent Systems for Molecular Biology conference. Anyone who has attended what is the largest computational biology conference since then has had the opportunity to join us for each birthday celebration—and receive 1 of our fun T-shirts as a party prize. Since launching, we have pushed our agenda of openness, transparency, reproducibility, and reusability. Here, we look back at our first 5 years and what we have done to forward our open science goals in scientific publishing. Our mainstay has been to create a process that allows the availability and publication of as many “research objects” as possible to create a more complete way of communicating how the research process is done. PMID:28938718
Astronaut Alan Bean flies the Astronaut Maneuvering Equipment

NASA Image and Video Library

1973-08-27

SL3-107-1215 (27 Aug. 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment in the forward dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. One of his fellow crewmen took this photograph with a 35mm Nikon camera. Bean is strapped into the back mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). The dome area is about 22 feet in diameter and 19 feet from top to bottom. Photo credit: NASA
Astronaut Alan Bean flies the Astronaut Maneuvering Equipment

NASA Image and Video Library

1973-08-18

SL3-108-1304 (July-September 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment in the forward dome area of the Orbital Workshop (OWS) on the space station cluster in Earth orbit. Bean is strapped in to the back-mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). This ASMU experiment is being done in shirt sleeves. The dome area where the experiment is conducted is about 22 feet in diameter and 19 feet from top to bottom. Photo credit: NASA
Detail view looking aft along the starboard side of the ...

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

Detail view looking aft along the starboard side of the Orbiter Discovery where the forward section meets the mid-fuselage. Note the head of the jack stand and its mechanism to connect to the one of the forward hoist attach points of the orbiter. Also note the support structure of the service platforms. This view was taken from the service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Looking Backwards, Looking Forwards: A Consideration of the Foibles of Action Research within Teacher Work

ERIC Educational Resources Information Center

Steele, Astrid

2012-01-01

This backward-looking reflection, which stems from experiences of an action research project with teachers, begins with an overview of current perspectives on action research in education settings. Significant details of the project are described to provide context for identification and discussion of the strengths and weaknesses relating to…
The use of forward looking infrared to locate bird carcasses in agricultural areas

USGS Publications Warehouse

Healy, J.M.

2001-01-01

Helicopter-mounted Forward Looking Infrared has mainly been used for large animal censuses. I examined the use of this instrument in locating bird carcasses in agricultural fields to improve current carcass searching techniques. Mallard (Arias platyrhynchos) and northern bobwhite quail (Colinus virginianus) carcasses were measured with an infrared thermometer immediately following death and for 5 consecutive nights to determine the optimal time for detection. Preliminary flights were conducted to design a protocol that was used in test flights. Bird species (mallard versus quail) and cover type (bare ground versus short grass) were compared in the flights. Carcasses were recovered with the aid of Global Positioning Systems. Carcasses remained above ambient ground temperatures for all or part of night 1. Quail carcass temperatures decreased faster than mallard carcasses. In warmer weather, carcass temperatures increased 3-5 nights following death. In colder weather, carcasses were 1-2 C cooler than the ground after the first night. Mallard and quail carcasses were both detected on bare ground and short grass cover types with Forward Looking Infrared. The carcass recovery rates were 40% arid 30% on bare ground and short grass, respectively. There were no significant differences in detection for species or cover type. In warmer weather, carcasses could be detected for several hours following death and again 3-5 nights after death. Carcasses may be detected as objects cooler than the ground in colder weather. Forward Looking Infrared was successful in detecting mallard and quail carcasses. Further research should evaluate improved mapping techniques to enhance carcass recovery.
[MSW incineration fly ash melting by DSC-DTA].

PubMed

Li, Rundong; Chi, Yong; Li, Shuiqing; Wang, Lei; Yan, Jianhua; Cen, Kefa

2002-07-01

Melting characteristics of two kinds of municipal solid waste incineration(MSWI) fly ash were studied in this paper by high temperature differential scanning calorimetry and differential temperature analysis. MSWI fly ash was considered as hazardous waste because it contains heavy metals and dioxins. The experiments were performed in either N2 or O2 atmosphere in temperature range of 20 degrees C-1450 degrees C at various heating rates. Two different MSW incineration fly ashes used in the experiments were collected from our country and France respectively. The process of fly ash melting exhibits two reactions occurring at temperature ranges of about 480 degrees C-670 degrees C and 1136 degrees C-1231 degrees C, respectively. The latent heat of polymorphic transformation and fusion were approximately 20 kJ/kg and 700 kJ/kg, while the total heat required for melting process was about 1800 kJ/kg. The paper also studied effect of CaO to melting. A heat flux thermodynamic model for fly ash melting was put forward and it agrees well with experimental data.
Coincidence and coherent data analysis methods for gravitational wave bursts in a network of interferometric detectors

NASA Astrophysics Data System (ADS)

Arnaud, Nicolas; Barsuglia, Matteo; Bizouard, Marie-Anne; Brisson, Violette; Cavalier, Fabien; Davier, Michel; Hello, Patrice; Kreckelbergh, Stephane; Porter, Edward K.

2003-11-01

Network data analysis methods are the only way to properly separate real gravitational wave (GW) transient events from detector noise. They can be divided into two generic classes: the coincidence method and the coherent analysis. The former uses lists of selected events provided by each interferometer belonging to the network and tries to correlate them in time to identify a physical signal. Instead of this binary treatment of detector outputs (signal present or absent), the latter method involves first the merging of the interferometer data and looks for a common pattern, consistent with an assumed GW waveform and a given source location in the sky. The thresholds are only applied later, to validate or not the hypothesis made. As coherent algorithms use more complete information than coincidence methods, they are expected to provide better detection performances, but at a higher computational cost. An efficient filter must yield a good compromise between a low false alarm rate (hence triggering on data at a manageable rate) and a high detection efficiency. Therefore, the comparison of the two approaches is achieved using so-called receiving operating characteristics (ROC), giving the relationship between the false alarm rate and the detection efficiency for a given method. This paper investigates this question via Monte Carlo simulations, using the network model developed in a previous article. Its main conclusions are the following. First, a three-interferometer network such as Virgo-LIGO is found to be too small to reach good detection efficiencies at low false alarm rates: larger configurations are suitable to reach a confidence level high enough to validate as true GW a detected event. In addition, an efficient network must contain interferometers with comparable sensitivities: studying the three-interferometer LIGO network shows that the 2-km interferometer with half sensitivity leads to a strong reduction of performances as compared to a network of three interferometers with full sensitivity. Finally, it is shown that coherent analyses are feasible for burst searches and are clearly more efficient than coincidence strategies. Therefore, developing such methods should be an important goal of a worldwide collaborative data analysis.
Looking back: forward looking.

PubMed

Edmunds, Scott C; Nogoy, Nicole A; Zauner, Hans; Li, Peter; Hunter, Christopher I; Zhe, Xiao Si; Goodman, Laurie

2017-09-01

GigaScience is now 5 years old, having been launched at the 2012 Intelligent Systems for Molecular Biology conference. Anyone who has attended what is the largest computational biology conference since then has had the opportunity to join us for each birthday celebration-and receive 1 of our fun T-shirts as a party prize. Since launching, we have pushed our agenda of openness, transparency, reproducibility, and reusability. Here, we look back at our first 5 years and what we have done to forward our open science goals in scientific publishing. Our mainstay has been to create a process that allows the availability and publication of as many "research objects" as possible to create a more complete way of communicating how the research process is done. © The Authors 2017. Published by Oxford University Press.
Intravascular forward-looking ultrasound transducers for microbubble-mediated sonothrombolysis.

PubMed

Kim, Jinwook; Lindsey, Brooks D; Chang, Wei-Yi; Dai, Xuming; Stavas, Joseph M; Dayton, Paul A; Jiang, Xiaoning

2017-06-14

Effective removal or dissolution of large blood clots remains a challenge in clinical treatment of acute thrombo-occlusive diseases. Here we report the development of an intravascular microbubble-mediated sonothrombolysis device for improving thrombolytic rate and thus minimizing the required dose of thrombolytic drugs. We hypothesize that a sub-megahertz, forward-looking ultrasound transducer with an integrated microbubble injection tube is more advantageous for efficient thrombolysis by enhancing cavitation-induced microstreaming than the conventional high-frequency, side-looking, catheter-mounted transducers. We developed custom miniaturized transducers and demonstrated that these transducers are able to generate sufficient pressure to induce cavitation of lipid-shelled microbubble contrast agents. Our technology demonstrates a thrombolysis rate of 0.7 ± 0.15 percent mass loss/min in vitro without any use of thrombolytic drugs.
Girls into Physics--Looking Back and Looking Forward

ERIC Educational Resources Information Center

Thomson, Clare

2011-01-01

Girls are under-represented in physics post-16. They continue to make up only 22% of those taking A-level Physics, despite the many changes in the educational system over the last 20 years. This article looks at the work the Institute of Physics has undertaken to address the issue. After outlining the key issues that were identified in work…
The contribution of medical physics to nuclear medicine: a physician's perspective.

PubMed

Ell, Peter J

2014-12-01

This paper is the second in a series of invited perspectives by four pioneers of nuclear medicine imaging and physics. A medical physicist and a nuclear medicine clinical specialist each take a backward look and a forward look at the contributions of physics to nuclear medicine. Here is a backward look from a nuclear medicine physician's perspective.
Women and the American Economy: A Look to the 1980's.

ERIC Educational Resources Information Center

Kreps, Juanita M., Ed.

The papers discuss the social and economic forces that have enabled women to explore new and expanding roles, and examine the profound effect the resulting changes are having and will continue to have on the economic and social potential of our nation. "Looking Backward in Order to Look Forward: Women, Work, and Social Values in America" puts the…
Report of the submillimeter splinter group

NASA Astrophysics Data System (ADS)

Harris, A. I.; Lequeux, J.

1992-12-01

The aim of the submillimeter splinter group of the LIST (Lunar Interferometry Study Team) was to examine the scientific and technical aspects of a submillimeter interferometer with an emphasis on heterodyne detection. The main elements of the scientific logic that lead to the conclusions that a heterodyne submillimeter array should have a collecting area of at order 1000 sq m are summarized. This conclusion is based on sensitivity constraints and the following points: anything that can be done from the ground, will be; an instrument as complex and expensive as a large submillimeter interferometer must be capable of significant extragalactic observations; and no matter what the future scientific trends are, looking at the main coolants will always be important. It is clear that an instrument of this size is several steps past the next generation of spaceborne observatories.
Trends in Community Development: Looking Back, Looking Forward.

ERIC Educational Resources Information Center

Miller, Chris; And Others

1990-01-01

Includes "Community Work in the U.K.: Reflections on the 1980s" (Miller, Bryant); "Multiplication and Divisions: Trends in Community Development in Ireland since the 1960s" (Cinneide, Walsh); "Reconstruction to Deconstruction: The Transformation of Community Work in Australia" (Meekosha; Mowbray): "Community…

Holographic optical coherence imaging of tumor spheroids

NASA Astrophysics Data System (ADS)

Yu, P.; Mustata, M.; Turek, J. J.; French, P. M. W.; Melloch, M. R.; Nolte, D. D.

2003-07-01

We present depth-resolved coherence-domain images of living tissue using a dynamic holographic semiconductor film. An AlGaAs photorefractive quantum-well device is used in an adaptive interferometer that records coherent backscattered (image-bearing) light from inside rat osteogenic sarcoma tumor spheroids up to 1 mm in diameter in vitro. The data consist of sequential holographic image frames at successive depths through the tumor represented as a visual video "fly-through." The images from the tumor spheroids reveal heterogeneous structures presumably caused by necrosis and microcalcifications characteristic of human tumors in their early avascular growth.
The GRB All-sky Spectrometer Experiment II: Data Collection and Analysis

NASA Astrophysics Data System (ADS)

Voigt, Elana; Martinot, Zachary; Banks, Zachary; Pober, Jonathan; Morales, Miguel F.

2015-01-01

The GRB All-sky Spectrometer Experiment (GASE) is a widefield interferometer radio telescope designed to look for Gamma Ray Bursts in the 30 to 50 MHz range. It is based and operated as a wholly undergraduate experiment at the University of Washington. This poster will focus on data analysis and the relation of data analysis to the commissioning process of our 8 element GASE array.
Look Forward to Take a Hike Day This Spring | Poster

Cancer.gov

Are you looking forward to spring? Join Occupational Health Services (OHS) and the R&W Club Frederick for the next Take a Hike Day in April. At the fall event, about 30 employees walked or jogged the 1.3-mile course around the NCI at Frederick campus during their lunch hours. The event is designed to encourage employees to engage in physical activity, according to Sarah Hooper, manager of OHS. “It was so wonderful to see employees walking to wellness,” said Emily Burnett, a Werner H. Kirsten student intern in OHS who helped plan the fall event.
STS-104 CDR Lindsey on forward flight deck prior to re-entry

NASA Image and Video Library

2001-07-25

STS104-345-021 (25 July 2001) --- Attired in his shuttle launch and entry suit, astronaut Steven W. Lindsey, STS-104 commander, looks over a procedures checklist at the commanders station on the forward flight deck of the space shuttle Atlantis.
A collection of the collapsed results of general tank tests of miscellaneous flying-boat-hull models

NASA Technical Reports Server (NTRS)

Locke, F W S , Jr

1947-01-01

Presented here are the summary charts of the collapsed results of general tank tests of about 100 flying boat hull models. These summary charts are intended to be used as an engineering tool to enable a flying boat designer to grasp more quickly the significance of various hull form parameters as they influence his particular airplane. The form in which the charts are prepared is discussed in some detail in order to make them clearer to the designer. This is a data report, and no attempt has been made to produce conclusions or correlations of the usual sort. However, some generalizations are put forward on the various methods in which summary charts may be used.
Astronaut Alan Bean flies the Astronaut Maneuvering Equipment in the OWS

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 Astronaut Maneuvering Equipment, as seen in this photographic reproduction taken from a television transmission made by a color television camera in the Orbital Workshop (OWS) of the Skylab space station in Earth orbit. Bean is strapped into the back-mounted, hand-controlled Automatically stabilized Maneuvering Unit (ASMU). The M509 exercise was in the forward dome area of the OWS. THe dome area is about 22 feet in diameter and 19 feet form top to bottom.
Length Contraction Should not be Independent of Time

NASA Astrophysics Data System (ADS)

Smarandache, Florentin

2013-10-01

In Special Theory of Relativity it looks that the length contraction along the direction of the motion is independent of time, i.e. if a rocket flies one second, or the rocket flies one year the rocket's along-the-motion length contraction is the same, since the contraction factor C (v) =√{ 1 -v2/c2 } depends on the rocket's relativistic speed (v) and on the light speed in vacuum (c) only. We find this as unrealistic, incomplete. It is logical that flying more and more it should increase the length contraction. What about the cosmic bodies that continuously travel, do they contract only once or are they continuously contracting?
Design of a nano-satellite demonstrator of an infrared imaging space interferometer: the HyperCube

NASA Astrophysics Data System (ADS)

Dohlen, Kjetil; Vives, Sébastien; Rakotonimbahy, Eddy; Sarkar, Tanmoy; Tasnim Ava, Tanzila; Baccichet, Nicola; Savini, Giorgio; Swinyard, Bruce

2014-07-01

The construction of a kilometer-baseline far infrared imaging interferometer is one of the big instrumental challenges for astronomical instrumentation in the coming decades. Recent proposals such as FIRI, SPIRIT, and PFI illustrate both science cases, from exo-planetary science to study of interstellar media and cosmology, and ideas for construction of such instruments, both in space and on the ground. An interesting option for an imaging multi-aperture interferometer with km baseline is the space-based hyper telescope (HT) where a giant, sparsely populated primary mirror is constituted of several free-flying satellites each carrying a mirror segment. All the segments point the same object and direct their part of the pupil towards a common focus where another satellite, containing recombiner optics and a detector unit, is located. In Labeyrie's [1] original HT concept, perfect phasing of all the segments was assumed, allowing snap-shot imaging within a reduced field of view and coronagraphic extinction of the star. However, for a general purpose observatory, image reconstruction using closure phase a posteriori image reconstruction is possible as long as the pupil is fully non-redundant. Such reconstruction allows for much reduced alignment tolerances, since optical path length control is only required to within several tens of wavelengths, rather than within a fraction of a wavelength. In this paper we present preliminary studies for such an instrument and plans for building a miniature version to be flown on a nano satellite. A design for recombiner optics is proposed, including a scheme for exit pupil re-organization, is proposed, indicating the focal plane satellite in the case of a km-baseline interferometer could be contained within a 1m3 unit. Different options for realization of a miniature version are presented, including instruments for solar observations in the visible and the thermal infrared and giant planet observations in the visible, and an algorithm for design of optimal aperture layout based on least-squares minimization is described. A first experimental setup realized by master students is presented, where a 20mm baseline interferometer with 1mm apertures associated with a thermal infrared camera pointed the sun. The absence of fringes in this setup is discussed in terms of spatial spectrum analysis. Finally, we discuss requirements in terms of satellite pointing requirements for such a miniature interferometer.
4. DETAIL VIEW, LOOKING SOUTH, ACROSS HULL NEAR BOW END, ...

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

4. DETAIL VIEW, LOOKING SOUTH, ACROSS HULL NEAR BOW END, TOP OF FORWARD STARBOARD CARGO HATCH IN FOREGROUND, OPENING FOR PORT HATCH BEYOND Edward Larrabee, photographer, November 1984 - Shooters Island, Ships Graveyard, Vessel No. 54, Newark Bay, Staten Island (subdivision), Richmond County, NY
Learning Later: A Special Issue to Mark the European Year of Older People and Solidarity between Generations.

ERIC Educational Resources Information Center

Tyler, William; And Others

1993-01-01

Includes "Older Learners" (Tyler); "Bridging the Gap at Strathclyde University" (Hart, Bissland); "Learning Later" (Harrison); "Looking back and Looking Forward" (Carter); "Is This the End for Older Learners?" (Schuller); "Producer or Dependent?" (Cooper); "Imaginations and…
Grappling with Globalization, Partnership, and Learning: A Look inside Oxfam America.

ERIC Educational Resources Information Center

Offenheiser, Raymond; Holcombe, Susan; Hopkins, Nancy

1999-01-01

Oxfam America is an international development and relief organization that is grappling with building a learning organization, creating constructive labor-management relations, and trying to position itself as one of the most effective, forward-looking nongovernmental organizations of the next century. (JOW)
An Adaptive Moving Target Imaging Method for Bistatic Forward-Looking SAR Using Keystone Transform and Optimization NLCS.

PubMed

Li, Zhongyu; Wu, Junjie; Huang, Yulin; Yang, Haiguang; Yang, Jianyu

2017-01-23

Bistatic forward-looking SAR (BFSAR) is a kind of bistatic synthetic aperture radar (SAR) system that can image forward-looking terrain in the flight direction of an aircraft. Until now, BFSAR imaging theories and methods for a stationary scene have been researched thoroughly. However, for moving-target imaging with BFSAR, the non-cooperative movement of the moving target induces some new issues: (I) large and unknown range cell migration (RCM) (including range walk and high-order RCM); (II) the spatial-variances of the Doppler parameters (including the Doppler centroid and high-order Doppler) are not only unknown, but also nonlinear for different point-scatterers. In this paper, we put forward an adaptive moving-target imaging method for BFSAR. First, the large and unknown range walk is corrected by applying keystone transform over the whole received echo, and then, the relationships among the unknown high-order RCM, the nonlinear spatial-variances of the Doppler parameters, and the speed of the mover, are established. After that, using an optimization nonlinear chirp scaling (NLCS) technique, not only can the unknown high-order RCM be accurately corrected, but also the nonlinear spatial-variances of the Doppler parameters can be balanced. At last, a high-order polynomial filter is applied to compress the whole azimuth data of the moving target. Numerical simulations verify the effectiveness of the proposed method.
Precision Attitude Control for the BETTII Balloon-Borne Interferometer

NASA Technical Reports Server (NTRS)

Benford, Dominic J.; Fixsen, Dale J.; Rinehart. Stephen

2012-01-01

The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII) is an 8-meter baseline far-infrared interferometer to fly on a high altitude balloon. Operating at wavelengths of 30-90 microns, BETTII will obtain spatial and spectral information on science targets at angular resolutions down to less than half an arcsecond, a capability unmatched by other far-infrared facilities. This requires attitude control at a level ofless than a tenth of an arcsecond, a great challenge for a lightweight balloon-borne system. We have designed a precision attitude determination system to provide gondola attitude knowledge at a level of 2 milliarcseconds at rates up to 100Hz, with accurate absolute attitude determination at the half arcsecond level at rates of up to 10Hz. A mUlti-stage control system involving rigid body motion and tip-tilt-piston correction provides precision pointing stability to the level required for the far-infrared instrument to perform its spatial/spectral interferometry in an open-loop control. We present key aspects of the design of the attitude determination and control and its development status.
Web Services Integration on the Fly

DTIC Science & Technology

2008-12-01

NETBEANS 6.1 AND VERSION CONTROL............................................28 1. NetBeans Integrated Development Environment (IDE) ................28 2...Forward and Reverse Engineering...................................................28 3. Implementation using NetBeans ...29 4. Subversion (SVN) for Version Control in NetBeans ......................29 O. PROTÉGÉ AUTHORING TOOL FOR SEMANTIC WEB
A Vision-Based Counting and Recognition System for Flying Insects in Intelligent Agriculture.

PubMed

Zhong, Yuanhong; Gao, Junyuan; Lei, Qilun; Zhou, Yao

2018-05-09

Rapid and accurate counting and recognition of flying insects are of great importance, especially for pest control. Traditional manual identification and counting of flying insects is labor intensive and inefficient. In this study, a vision-based counting and classification system for flying insects is designed and implemented. The system is constructed as follows: firstly, a yellow sticky trap is installed in the surveillance area to trap flying insects and a camera is set up to collect real-time images. Then the detection and coarse counting method based on You Only Look Once (YOLO) object detection, the classification method and fine counting based on Support Vector Machines (SVM) using global features are designed. Finally, the insect counting and recognition system is implemented on Raspberry PI. Six species of flying insects including bee, fly, mosquito, moth, chafer and fruit fly are selected to assess the effectiveness of the system. Compared with the conventional methods, the test results show promising performance. The average counting accuracy is 92.50% and average classifying accuracy is 90.18% on Raspberry PI. The proposed system is easy-to-use and provides efficient and accurate recognition data, therefore, it can be used for intelligent agriculture applications.
A Vision-Based Counting and Recognition System for Flying Insects in Intelligent Agriculture

PubMed Central

Zhong, Yuanhong; Gao, Junyuan; Lei, Qilun; Zhou, Yao

2018-01-01

Rapid and accurate counting and recognition of flying insects are of great importance, especially for pest control. Traditional manual identification and counting of flying insects is labor intensive and inefficient. In this study, a vision-based counting and classification system for flying insects is designed and implemented. The system is constructed as follows: firstly, a yellow sticky trap is installed in the surveillance area to trap flying insects and a camera is set up to collect real-time images. Then the detection and coarse counting method based on You Only Look Once (YOLO) object detection, the classification method and fine counting based on Support Vector Machines (SVM) using global features are designed. Finally, the insect counting and recognition system is implemented on Raspberry PI. Six species of flying insects including bee, fly, mosquito, moth, chafer and fruit fly are selected to assess the effectiveness of the system. Compared with the conventional methods, the test results show promising performance. The average counting accuracy is 92.50% and average classifying accuracy is 90.18% on Raspberry PI. The proposed system is easy-to-use and provides efficient and accurate recognition data, therefore, it can be used for intelligent agriculture applications. PMID:29747429
Windshear certification data base for forward-look detection systems

NASA Technical Reports Server (NTRS)

Switzer, George F.; Hinton, David A.; Proctor, Fred H.

1994-01-01

Described is an introduction to a comprehensive database that is to be used for certification testing of airborne forward-look windshear detection systems. The database was developed by NASA Langley Research Center, at the request of the Federal Aviation Administration (FAA), to support the industry initiative to certify and produce forward-looking windshear detection equipment. The database contains high-resolution three-dimensional fields for meteorological variables that may be sensed by forward-looking systems. The database is made up of seven case studies that are generated by the Terminal Area Simulation System, a state-of-the-art numerical system for the realistic modeling of windshear phenomena. The selected cases contained in the certification documentation represent a wide spectrum of windshear events. The database will be used with vendor-developed sensor simulation software and vendor-collected ground-clutter data to demonstrate detection performance in a variety of meteorological conditions using NASA/FAA pre-defined path scenarios for each of the certification cases. A brief outline of the contents and sample plots from the database documentation are included. These plots show fields of hazard factor, or F-factor (Bowles 1990), radar reflectivity, and velocity vectors on a horizontal plane overlayed with the applicable certification paths. For the plot of the F-factor field the region of 0.105 and above signify an area of hazardous, performance decreasing windshear, while negative values indicate regions of performance increasing windshear. The values of F-factor are based on 1-Km averaged segments along horizontal flight paths, assuming an air speed of 150 knots (approx. 75 m/s). The database has been released to vendors participating in the certification process. The database and associated document have been transferred to the FAA for archival storage and distribution.
Flying by the Death

NASA Image and Video Library

2010-03-29

In this view captured by NASA Cassini spacecraft on its closest-ever flyby of Saturn moon Mimas, large Herschel Crater dominates Mimas, making the moon look like the Death Star in the movie Star Wars.
Proteinases, their receptors and inflammatory signalling: the Oxford South Parks Road connection*

PubMed Central

Hollenberg, M D

2015-01-01

In keeping with the aim of the Paton Memorial Lecture to ‘facilitate the historical study of pharmacology’, this overview, which is my distinct honour to write, represents a ‘Janus-like’ personal perspective looking both backwards and forwards at the birth and growth of ‘receptor molecular pharmacology’ with special relevance to inflammatory diseases. The overview begins in the Oxford Department of Pharmacology in the mid-1960s and then goes on to provide a current perspective of signalling by proteinases. Looking backwards, the synopsis describes the fruitful Oxford Pharmacology Department infrastructure that Bill Paton generated in keeping with the blueprint begun by his predecessor, J H Burn. Looking forwards, the overview illustrates the legacy of that environment in generating some of the first receptor ligand-binding data and providing the inspiration and vision for those like me who were training in the department at the same time. With apologies, I mention only in passing a number of individuals who benefitted from the ‘South Parks Road connection’ using myself as one of the ‘outcome study’ examples. It is also by looking forward that I can meet the complementary aim of summarizing the lecture presented at a ‘BPS 2014 Focused Meeting on Cell Signalling’ to provide an overview of the role of proteinases and their signalling mechanisms in the setting of inflammation. PMID:25521749
Gone with the Wind: Conceiving of Moral Responsibility in the Case of GMO Contamination.

PubMed

Robaey, Zoë

2016-06-01

Genetically modified organisms are a technology now used with increasing frequency in agriculture. Genetically modified seeds have the special characteristic of being living artefacts that can reproduce and spread; thus it is difficult to control where they end up. In addition, genetically modified seeds may also bring about uncertainties for environmental and human health. Where they will go and what effect they will have is therefore very hard to predict: this creates a puzzle for regulators. In this paper, I use the problem of contamination to complicate my ascription of forward-looking moral responsibility to owners of genetically modified organisms. Indeed, how can owners act responsibly if they cannot know that contamination has occurred? Also, because contamination creates new and unintended ownership, it challenges the ascription of forward-looking moral responsibility based on ownership. From a broader perspective, the question this paper aims to answer is as follows: how can we ascribe forward-looking moral responsibility when the effects of the technologies in question are difficult to know or unknown? To solve this problem, I look at the epistemic conditions for moral responsibility and connect them to the normative notion of the social experiment. Indeed, examining conditions for morally responsible experimentation helps to define a range of actions and to establish the related epistemic virtues that owners should develop in order to act responsibly where genetically modified organisms are concerned.

Telescopes in Near Space: Balloon Exoplanet Nulling Interferometer (BigBENI)

NASA Technical Reports Server (NTRS)

Lyon, Richard G.; Clampin, Mark; Petrone, Peter; Mallik, Udayan; Mauk, Robin

2012-01-01

A significant and often overlooked path to advancing both science and technology for direct imaging and spectroscopic characterization of exosolar planets is to fly "near space" missions, i.e. balloon borne exosolar missions. A near space balloon mission with two or more telescopes, coherently combined, is capable of achieving a subset of the mission science goals of a single large space telescope at a small fraction of the cost. Additionally such an approach advances technologies toward flight readiness for space flight. Herein we discuss the feasibility of flying two 1.2 meter telescopes, with a baseline separation of 3.6 meters, operating in visible light, on a composite boom structure coupled to a modified visible nulling coronagraph operating to achieve an inner working angle of 60 milli-arcseconds. We discuss the potential science return, atmospheric residuals at 135,000 feet, pointing control and visible nulling and evaluate the state-or-art of these technologies with regards to balloon missions.
Exercise your physics when flying

NASA Astrophysics Data System (ADS)

Baffa, Oswaldo

1999-10-01

Recently, while flying, I found it difficult to sleep and started to pay attention to the television screens in the airplane. There were two types of TV to watch—a large cathode raye tube (CRT)monitor and smaller liquid crystal display (LCD) for passengers sitting near the bulkhead. In one of my glances at the large monitors I noticed that the colors were changing. I looked at the LCD monitors and the colors were fine. What could be happening?
Looking Forward to Look Backward: Technology and King Arthur

ERIC Educational Resources Information Center

Thomas, Jennifer D. E.; Driver, Martha; Coppola, Jean F.; Thomas, Barbara A.

2008-01-01

This article discusses students' perceptions of the impact of technology integration in an interdisciplinary medieval English literature and multimedia course on developing higher-order thinking skills and team-building skills. The results indicate that undergraduate students in this course perceived generally strong support for development of…
EDITORIAL A Quarter-Century of Immunotoxicology: Looking Back, Looking Forward

EPA Science Inventory

The Immunotoxicology Specialty Section of the Society of Toxicology celebrated its 25th anniversary at the 2010 Annual Meeting, prompting us to provide here both an historical perspective and an assessment of the challenges that lie ahead for this sub-discipline of toxicology. In...
Looking Forward, Looking Back: Anticipation is More Evocative than Retrospection

ERIC Educational Resources Information Center

Van Boven, Leaf; Ashworth, Laurence

2007-01-01

The results of 5 experiments indicate that people report more intense emotions during anticipation of, than during retrospection about, emotional events that were positive (Thanksgiving Day), negative (annoying noises, menstruation), routine (menstruation), and hypothetical (all-expenses-paid ski vacation). People's tendency to report more intense…
30. View of main deck at bow (looking aft from ...

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

30. View of main deck at bow (looking aft from samson post, upper deck removed), showing anchor windlass (left foreground), head (right foregound), and forward deckhouse; weather canopy overhead not an original or permanent feature - Schooner WAWONA, 1018 Valley Street, Seattle, King County, WA
Our Solar System, from the Outside

NASA Image and Video Library

2011-04-28

This graphic, based on data from NASA Voyager spacecraft, shows a model of what our solar system looks like to an observer outside in interstellar space, watching our solar system fly towards the observer.
Darwin : the technical challenges of an optical nulling interferometer in space

NASA Astrophysics Data System (ADS)

Viard, Thierry; Lund, Glenn; Thomas, Eric; Vacance, Michel

2017-11-01

Alcatel Space has been responsible for a feasibility study contract, awarded by the European Space Agency, and dedicated to the definition of preliminary interferometric concepts for the direct detection and characterisation of exo-planets associated with nearby stars. The retained concept is a six free-flyer-telescope interferometer, with a variable baseline ranging from 50 to 500 m. The collected wavefronts are combined on a 7th free-flying hub satellite at the centre of the array, and the observations are performed in the thermal Infra-Red spectral band. The latter choice is made for two reasons : firstly, the wavelength providing optimal contrast between the planetary and stellar (background) signals is approximately 10μm secondly, the spectral features of interest for the detection of life as we know it (CO2, H2O, O3 , CH4 ... ) lie in the band between 6 and 18 μm. The system requirements for such an instrument are very severe, owing to the physical nature of the mission concept; i.e. that of a coronographic stellar interferometer: in order to achieve satisfactory extinction of the unwanted flux generated by the central star, such a concept will impose the control of optical pathlength differences between telescopes to within a small fraction of a wavelength, milli-arcsec pointing stabilities, 10-3 amplitude equalisation, achromatic check-shifts of some beams with respect to the others, and the use of passively cooled cryogenic telescopes.
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, KSC employee Chris Moore repairs tile on the forward area of the orbiter Discovery. The vehicle has undergone Orbiter Major Modifications in the past year, which includes tile check and repair. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000° Fahrenheit, which are produced during descent for landing. Discovery is scheduled to fly on mission STS-121 to the International Space Station.

NASA Image and Video Library

2003-12-09

KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, KSC employee Chris Moore repairs tile on the forward area of the orbiter Discovery. The vehicle has undergone Orbiter Major Modifications in the past year, which includes tile check and repair. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000° Fahrenheit, which are produced during descent for landing. Discovery is scheduled to fly on mission STS-121 to the International Space Station.
Ultra-sensitive inertial sensors via neutral-atom interferometry

NASA Technical Reports Server (NTRS)

Clauser, John F.

1989-01-01

Upon looking at the various colossal interferometers, etc., discussed at this conference to test gravitational theory, one cannot avoid feeling that easier approaches exist. The use of low velocity, neutral atom matter waves in place of electromagnetic waves in sensitive inertial interferometer configurations is proposed. For applications, spacecraft experiments to sense a drag-free condition, to measure the Lense-Thirring precession, to measure the gravitomagnetic effect and/or the earth's geopotential (depending on altitude), and to detect long period gravitational waves are considered. Also, a terrestrial precision test of the equivalence principle on spin polarized atoms, capable of detecting effects of the 5th force is considered. While the ideas described herein are preliminary, the orders of magnitude are sufficiently tantalizing to warrant further study. Although existing proposed designs may be adequate for some of these experiments, the use of matter-wave interferometry offers reduced complexity and cost, and an absence of cryogenics.
Interior view of the Flight Deck looking forward, the Commander's ...

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

Interior view of the Flight Deck looking forward, the Commander's seat and controls are on the left and the pilot's seat and controls are on the right of the view. Note that the flight deck windows have protective covers over them in this view. This images can be digitally stitched with image HAER No. TX-116-A-20 to expand the view to include the overhead control panels of the flight deck. This view was taken in the Orbiter Processing Facility at the Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Forward-looking automotive radar sensor

NASA Astrophysics Data System (ADS)

Ganci, Paul; Potts, Steven; Okurowski, Frank

1995-12-01

For intelligent cruise control (ICC) and forward looking collision warning systems to be successful products they must provide robust performance in a complex roadway environment. Inconveniences caused by dropped tracks and nuisance alarms will not be tolerated by consumers, and would likely result in rejection of these new technologies in the marketplace. The authors report on a low-cost automotive millimeter wave (MMW) radar design which addresses shortcomings associated with previously reported ICC system implementations. The importance of the sensor's ability to identify and separately track all obstacles in the field of view is discussed. The applicability of the MMW's FM-CW sensor implementation to collision warning systems is also discussed.
Trends in Correlation-Based Pattern Recognition and Tracking in Forward-Looking Infrared Imagery

PubMed Central

Alam, Mohammad S.; Bhuiyan, Sharif M. A.

2014-01-01

In this paper, we review the recent trends and advancements on correlation-based pattern recognition and tracking in forward-looking infrared (FLIR) imagery. In particular, we discuss matched filter-based correlation techniques for target detection and tracking which are widely used for various real time applications. We analyze and present test results involving recently reported matched filters such as the maximum average correlation height (MACH) filter and its variants, and distance classifier correlation filter (DCCF) and its variants. Test results are presented for both single/multiple target detection and tracking using various real-life FLIR image sequences. PMID:25061840
An analysis of the economic impact of the AN/APS-134 FLAR (Forward Looking Airborne Radar) retrofit on Coast Guard HC-130 aircraft

NASA Astrophysics Data System (ADS)

Dunn, R. E.

1984-12-01

Concern over the growing drug smuggling problem and improved national defense capability are manifest in the need for a new forward looking airborne radar (FLAR) for Coast Guard HC-130 aircraft, with a capability of detecting a target of 1 square meter radar cross section. This thesis reexamines the analysis that selected the AN/APS-134 FLAR over other contenders based on mission need, radar performance and life cycle cost criteria. This thesis presents a better understanding of the resulting HC-130 force structure based on the impact of FLAR technology.
Knowledge, Difference, and Power: Essays Inspired by "Women's Ways of Knowing."

ERIC Educational Resources Information Center

Goldberger, Nancy Rule, Ed.; Tarule, Jill Mattuck, Ed.; Clinchy, Blythe McVicker, Ed.; Belenky, Mary Field, Ed.

This book contains 14 essays exploring how the theory of women's psychology, development, and ways of knowing has developed during the past decade. The following essays are included: "The Beginning of the Story: Collaboration and Separation" (Nancy Rule Goldberger); "Looking Backward, Looking Forward" (Nancy Rule Goldberger);…
22. INTERIOR VIEW OF TYPICAL OIL TANK, PORT SIDE, LOOKING ...

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

22. INTERIOR VIEW OF TYPICAL OIL TANK, PORT SIDE, LOOKING FORWARD. NOTE SHIP'S FRAMING MEMBERS AND UNIVERSAL JOINT IN SHAFT FOR PUMPING VALVE AT BOTTOM OF TANK. THE ACCESS LADDER STEPS ARE MARKED WITH LEVEL INDICATIONS. - Ship "Falls of Clyde", Hawaii Maritime Center, Pier 7, Honolulu, Honolulu County, HI
Understanding Women's Achievement Choices: Looking Back and Looking Forward

ERIC Educational Resources Information Center

Eccles, Jacquelynne S.

2011-01-01

In this commentary, the author talks about her two articles in "Psychology of Women Quarterly" (PWQ): (1) the 1987 article entitled "Gender Roles and Women's Achievement-Related Decisions"; and (2) the 1994 article entitled "Understanding Women's Educational and Occupational Choices." The original articles can be found at…
STS-116 Crewmembers Polansky and Oefelein look over crew procedures in the FWD FD on Space Shuttle Discovery

NASA Image and Video Library

2006-12-21

S116-E-07787 (21 Dec. 2006) --- Astronauts Mark L. Polansky (left) and William A. (Bill) Oefelein, STS-116 commander and pilot, respectively, look over procedures checklists on the forward flight deck of Space Shuttle Discovery during flight day 13 activities.
General view of the middeck area looking forward and starboard. ...

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

General view of the mid-deck area looking forward and starboard. On the far left of the images are the avionics equipment bays. During missions the forward avionics bays would be fronted by lockers for mission equipment and the flight crew's personal equipment. Sleep stations would be located along the far wall if the orbiter was in a flight ready configuration. The hose and ladder on the right side of the image are pieces of ground support equipment. The hose is part of the climate control apparatus used while orbiters are being processed. The ladder is used to access the inter-deck passage, leading to the flight deck, while the orbiter is in 1g (earth's gravity). This view was taken in the Orbiter Processing Facility at the Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Satellite and airborne IR sensor validation by an airborne interferometer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gumley, L.E.; Delst, P.F. van; Moeller, C.C.

1996-11-01

The validation of in-orbit longwave IR radiances from the GOES-8 Sounder and inflight longwave IR radiances from the MODIS Airborne Simulator (MAS) is described. The reference used is the airborne University of Wisconsin High Resolution Interferometer Sounder (HIS). The calibration of each sensor is described. Data collected during the Ocean Temperature Interferometric Survey (OTIS) experiment in January 1995 is used in the comparison between sensors. Detailed forward calculations of at-sensor radiance are used to account for the difference in GOES-8 and HIS altitude and viewing geometry. MAS radiances and spectrally averaged HIS radiances are compared directly. Differences between GOES-8 andmore » HIS brightness temperatures, and GOES-8 and MAS brightness temperatures, are found to be with 1.0 K for the majority of longwave channels examined. The same validation approach will be used for future sensors such as the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Atmospheric Infrared Sounder (AIRS). 11 refs., 2 figs., 4 tabs.« less

Design and evaluation of a Stochastic Optimal Feed-forward and Feedback Technology (SOFFT) flight control architecture

NASA Technical Reports Server (NTRS)

Ostroff, Aaron J.; Proffitt, Melissa S.

1994-01-01

This paper describes the design and evaluation of a stochastic optimal feed-forward and feedback technology (SOFFT) control architecture with emphasis on the feed-forward controller design. The SOFFT approach allows the designer to independently design the feed-forward and feedback controllers to meet separate objectives and then integrate the two controllers. The feed-forward controller has been integrated with an existing high-angle-of-attack (high-alpha) feedback controller. The feed-forward controller includes a variable command model with parameters selected to satisfy level 1 flying qualities with a high-alpha adjustment to achieve desired agility guidelines, a nonlinear interpolation approach that scales entire matrices for approximation of the plant model, and equations for calculating feed-forward gains developed for perfect plant-model tracking. The SOFFT design was applied to a nonlinear batch simulation model of an F/A-18 aircraft modified for thrust vectoring. Simulation results show that agility guidelines are met and that the SOFFT controller filters undesired pilot-induced frequencies more effectively during a tracking task than a flight controller that has the same feedback control law but does not have the SOFFT feed-forward control.
Formation Flying: The Future of Remote Sensing from Space

NASA Technical Reports Server (NTRS)

Leitner, Jesse

2004-01-01

Over the next two decades a revolution is likely to occur in how remote sensing of Earth, other planets or bodies, and a range of phenomena in the universe is performed from space. In particular, current launch vehicle fairing volume and mass constraints will continue to restrict the size of monolithic telescope apertures which can be launched to accommodate only slightly more performance capability than is achievable today, such as by the Hubble Space Telescope. Systems under formulation today, such as the James Webb Space Telescope will be able to increase aperture size and, hence, imaging resolution, by deploying segmented optics. However, this approach is limited as well, by ow ability to control such segments to optical tolerances over long distances with highly uncertain structural dynamics connecting them. Consequently, for orders of magnitude improved resolution as required for imaging black holes, imaging planets, or performing asteroseismology, the only viable approach will be to fly a collection of spacecraft in formation to synthesize a virtual segmented telescope or interferometer with very large baselines. This presentation describes some of the strategic science missions planned in the National Aeronautics and Space Administration, and identifies some of the critical technologies needed to enable some of the most challenging space missions ever conceived which have realistic hopes of flying.
Spacecraft Formation Flying: An Overview of Missions and Technologies

NASA Technical Reports Server (NTRS)

Leitner, Jesse

2007-01-01

Over the next two decades a revolution is likely to occur in how remote sensing of Earth, other planets or bodies, and a range of phenomena in the universe is performed from space. In particular, current launch vehicle fairing volume and mass constraints will continue to restrict the size of monolithic telescope apertures which can be launched to accommodate only slightly more performance capability than is achievable today, such as by the Hubble Space Telescope. Systems under formulation today, such as the James Webb Space Telescope, will be able to increase aperture size and, hence, imaging resolution, by deploying segmented optics. However, this approach is limited as well, by our ability to control such segments to optical tolerances over long distances with highly uncertain structural dynamics connecting them. Consequently, for orders of magnitude improved resolution as required for imaging black holes, imaging planets, or performing asteroseismology, the only viable approach will be to fly a collection of spacecraft in formation to synthesize a virtual segmented telescope or interferometer with very large baselines. This presentation highlights some of the strategic science missions planned in the National Aeronautics and Space Administration, and identifies some of the critical technologies needed to enable some of the most challenging space missions ever conceived which have realistic hopes of flying.
Flying Past Pluto Animation

NASA Image and Video Library

2015-08-28

This dramatic view of the Pluto system is as NASA's New Horizons spacecraft saw it in July 2015. The animation, made with real images taken by New Horizons, begins with Pluto flying in for its close-up on July 14; we then pass behind Pluto and see the atmosphere glow in sunlight before the sun passes behind Pluto's largest moon, Charon. The movie ends with New Horizons' departure, looking back on each body as thin crescents. http://photojournal.jpl.nasa.gov/catalog/PIA19873
FIREX mission requirements document for nonrenewable resources

NASA Technical Reports Server (NTRS)

Dixon, T.; Carsey, F.

1982-01-01

The proposed mission requirements and a proposed experimental program for satellite synthetic aperture radar (SAR) system named FIREX (Free-Flying Imaging Radar Experiment) for nonrenewable resources is described. The recommended spacecraft minimum SAR system is a C-band imager operating in four modes: (1) low look angle HH-polarized; (2) intermediate look angle, HH-polarized; (3) intermediate look angle, IIV-polarized; and (4) high look angle HH-polarized. This SAR system is complementary to other future spaceborne imagers such as the Thematic Mapper on LANDSAT-D. A near term aircraft SAR based research program is outlined which addresses specific mission design issues such as preferred incidence angles or polarizations for geologic targets of interest.
Fly in Atmosphere by Drag Force - Easy Thrust Generation Aircraft Engine Based Physics

NASA Astrophysics Data System (ADS)

Pierre Celestin, Mwizerwa

2013-11-01

This paper aims to present to the science community another way to fly in atmosphere, a way which is much more cheaper, efficient, safe and easy. Over the years scientists have been trying to find a way to built the vertically taking off vehicles but there have been no satisfactory success(what have been found was very expensive), Even aircrafts we know now need very sophisticated and expensive engines and not efficient enough. This way of flying may help our governments to spend less money on technologies and will help people to travel at very low prices so that, it may be a solution to the crisis which the world faces nowadays. In other words, it is my proposal to the next generation technologies we was looking for for years because everything can fly from the car to the trucks, the spaceships and even the hotels maybe constructed and fly as we construct the ships which sail in the oceans. My way of flying will have many applications in all the aspect of travel as it is going to be explained.
Automated vehicle detection in forward-looking infrared imagery.

PubMed

Der, Sandor; Chan, Alex; Nasrabadi, Nasser; Kwon, Heesung

2004-01-10

We describe an algorithm for the detection and clutter rejection of military vehicles in forward-looking infrared (FLIR) imagery. The detection algorithm is designed to be a prescreener that selects regions for further analysis and uses a spatial anomaly approach that looks for target-sized regions of the image that differ in texture, brightness, edge strength, or other spatial characteristics. The features are linearly combined to form a confidence image that is thresholded to find likely target locations. The clutter rejection portion uses target-specific information extracted from training samples to reduce the false alarms of the detector. The outputs of the clutter rejecter and detector are combined by a higher-level evidence integrator to improve performance over simple concatenation of the detector and clutter rejecter. The algorithm has been applied to a large number of FLIR imagery sets, and some of these results are presented here.
The Effects of Synthetic and Enhanced Vision Technologies for Lunar Landings

NASA Technical Reports Server (NTRS)

Kramer, Lynda J.; Norman, Robert M.; Prinzel, Lawrence J., III; Bailey, Randall E.; Arthur, Jarvis J., III; Shelton, Kevin J.; Williams, Steven P.

2009-01-01

Eight pilots participated as test subjects in a fixed-based simulation experiment to evaluate advanced vision display technologies such as Enhanced Vision (EV) and Synthetic Vision (SV) for providing terrain imagery on flight displays in a Lunar Lander Vehicle. Subjects were asked to fly 20 approaches to the Apollo 15 lunar landing site with four different display concepts - Baseline (symbology only with no terrain imagery), EV only (terrain imagery from Forward Looking Infra Red, or FLIR, and LIght Detection and Ranging, or LIDAR, sensors), SV only (terrain imagery from onboard database), and Fused EV and SV concepts. As expected, manual landing performance was excellent (within a meter of landing site center) and not affected by the inclusion of EV or SV terrain imagery on the Lunar Lander flight displays. Subjective ratings revealed significant situation awareness improvements with the concepts employing EV and/or SV terrain imagery compared to the Baseline condition that had no terrain imagery. In addition, display concepts employing EV imagery (compared to the SV and Baseline concepts which had none) were significantly better for pilot detection of intentional but unannounced navigation failures since this imagery provided an intuitive and obvious visual methodology to monitor the validity of the navigation solution.
Astronaut Alan Bean flies the Astronaut Maneuvering Equipment in the OWS

NASA Image and Video Library

1973-08-28

S73-34207 (28 Aug. 1973) --- Astronaut Alan L. Bean, Skylab 3 commander, flies the M509 astronaut Maneuvering Equipment, as seen in this photographic reproduction taken from a television transmission made by a color television camera in the Orbital Workshop (OWS) of the Skylab space station in Earth orbit. Bean is strapped into the back-mounted, hand-controlled Automatically Stabilized Maneuvering Unit (ASMU). The M509 exercise was in the forward dome area of the OWS. The dome area is about 22 feet in diameter and 19 feet from top to bottom. Photo credit: NASA
Distributed control topologies for deep space formation flying spacecraft

NASA Technical Reports Server (NTRS)

Hadaegh, F. Y.; Smith, R. S.

2002-01-01

A formation of satellites flying in deep space can be specified in terms of the relative satellite positions and absolute satellite orientations. The redundancy in the relative position specification generates a family of control topologies with equivalent stability and reference tracking performance, one of which can be implemented without requiring communication between the spacecraft. A relative position design formulation is inherently unobservable, and a methodology for circumventing this problem is presented. Additional redundancy in the control actuation space can be exploited for feed-forward control of the formation centroid's location in space, or for minimization of total fuel consumption.
Operational Implementation Design for the Earth System Prediction Capability (ESPC): A First-Look

DTIC Science & Technology

2014-02-20

Hybrid NAVDAS-AR data assimilation system assisting by providing dynamic estimates of the error in the background forecasts. 2.1.2 NAVDAS-AR – the...directly assimilates radiances from microwave radiometers and from interferometers and spectrometers in the infrared, and bending angle from Global...real-time analysis (at +3:00). Late in the 12-hr watch (around +8:00), a post-time NAVGEM/NAVDAS-AR run generates the background fields for the next
Evaluation of ternary cementitious combinations.

DOT National Transportation Integrated Search

2012-02-01

Portland cement concrete (PCC) is the worlds most versatile and most used construction materials. Global demand for PCC sustainability has risen as of late. To meet that need, engineers have looked to alternative binders such as fly ash, silica fu...
Looking Back/Looking Forward. 1999 Tenth Anniversary Report.

ERIC Educational Resources Information Center

Florida Education and Employment Council for Women and Girls.

This document outlines the mission and accomplishments of the Florida Education and Employment Council for Women and Girls. Presented first is a statement of the council's mission, which includes the following: develop public consciousness of the talents of all women; encourage women and girls to become actively involved in education and training…
The Year in Review, And a Look Ahead, Too.

ERIC Educational Resources Information Center

Novelli, Joan

1995-01-01

This article presents easy computer projects to send students into the summer feeling good about the past year and looking forward to the next. The projects involve printing summer reading book lists, making bridges to the next grade, publishing books of class events, designing reading posters, and creating summer calendars. (SM)
Revisiting "Grutter" and "Gratz" in the Wake of "Fisher": Looking Back to Move Forward

ERIC Educational Resources Information Center

Ledesma, Maria C.

2013-01-01

This article revisits the University of Michigan's 2003 affirmative action cases, "Grutter v. Bollinger" and "Gratz v. Bollinger." Through the aid of critical textual analysis and critical race theory, the author looks back at the predominant narratives that framed the challenge to, and defense of, race-conscious affirmative…
Physics and the Art of Teaching.

ERIC Educational Resources Information Center

Wise, Alice

The science of physics teaches the world to look beyond what is known and to be creative about visions of the future. Educators, like scientists, are responsible for pointing forward, for looking around and beyond the realm of what is known, to the realm of what could be. Yet, most institutions are restrained by traditional frameworks. Education…
Hidden, Unacknowledged, Acquaintance, and Date Rape: Looking Back, Looking Forward

ERIC Educational Resources Information Center

Koss, Mary P.

2011-01-01

In this commentary, the author reflects on two articles that have been among the most highly cited publications in "Psychology of Women Quarterly" ("PWQ") over its first 35 years, "The Hidden Rape Victim: Personality, Attitudinal, and Situational Characteristics" (Koss, 1985) and "Stranger and Acquaintance Rape: Are There Differences in the…
The Professional Development of Future Professors of Foreign Languages: Looking Back, Looking Forward

ERIC Educational Resources Information Center

Allen, Heather Willis; Negueruela-Azarola, Eduardo

2010-01-01

Although the professional development of graduate students in foreign language (FL) departments is of critical importance, discussion of its significance and evolution was all but absent in the 2007 Modern Language Association report "Foreign Languages and Higher Education: New Structures for a Changed World," a document advocating curricular and…
From College to University: Looking Backwards, Looking Forwards

ERIC Educational Resources Information Center

Christie, Hazel; Cree, Viviene E.; Hounsell, Jenny; McCune, Velda; Tett, Lyn

2006-01-01

This paper reports on the first phase of a study of the experiences of a small group of students (35) that have entered an "elite" Scottish university directly from Further Education (FE) colleges where they have studied Higher National Certificate and Diploma courses. Students' experiences were gathered through in-depth interviews and a…
Programmes of Educational Technology in China: Looking Backward, Thinking Forward

ERIC Educational Resources Information Center

Fuyin, Xu; Jianli, Jiao

2010-01-01

There is a history of programmes in educational technology in colleges and universities in China going back about 70 years. This paper briefly reviews the developmental history of the educational technology programme in China, elaborates the status-quo of the programme and looks ahead into the future trends of educational technology development in…

Traumatic Brain Injury: Looking Back, Looking Forward

ERIC Educational Resources Information Center

Bartlett, Sue; Lorenz, Laura; Rankin, Theresa; Elias, Eileen; Weider, Katie

2011-01-01

This article is the eighth of a multi-part series on traumatic brain injury (TBI). Historically, TBI has received limited national attention and support. However, since it is the signature injury of the military conflicts in Iraq and Afghanistan, TBI has gained attention of elected officials, military leaders, policymakers, and the public. The…
Network Analysis in Community Psychology: Looking Back, Looking Forward.

PubMed

Neal, Zachary P; Neal, Jennifer Watling

2017-09-01

Network analysis holds promise for community psychology given the field's aim to understand the interplay between individuals and their social contexts. Indeed, because network analysis focuses explicitly on patterns of relationships between actors, its theories and methods are inherently extra-individual in nature and particularly well suited to characterizing social contexts. But, to what extent has community psychology taken advantage of this network analysis as a tool for capturing context? To answer these questions, this study provides a review of the use network analysis in articles published in American Journal of Community Psychology. Looking back, we describe and summarize the ways that network analysis has been employed in community psychology research to understand the range of ways community psychologists have found the technique helpful. Looking forward and paying particular attention to analytic issues identified in past applications, we provide some recommendations drawn from the network analysis literature to facilitate future applications of network analysis in community psychology. © 2017 The Authors. American Journal of Community Psychology published by Wiley Periodicals, Inc. on behalf of Society for Community Research and Action.
KSC-2009-3199

NASA Image and Video Library

2009-05-17

CAPE CANAVERAL, Fla. – In the Assembly and Refurbishment Facility at NASA's Kennedy Space Center in Florida, technicians look closely as the Ares I-X forward skirt is mated to the forward skirt extension.. The forward skirt is the initial piece of first-stage hardware in preparation for the August 2009 test flight of NASA's next-generation spacecraft and launch vehicle system. Built entirely of armored steel, the 14,000-pound segment is seven feet tall and 12-1/4 feet wide. Photo credit: NASA/Tim Jacobs
Arrows of Time in Infancy: The Representation of Temporal-Causal Invariances

ERIC Educational Resources Information Center

Friedman, William J.

2002-01-01

Many transformations that take place over time can only occur in one temporal direction, and adults are highly sensitive to the differences between forward and backward presentations of such events. In seven experiments using two selective-looking paradigms, 4- and 8-month-olds were shown forward and backward videotapes of events involving the…
STS-27 Atlantis - OV-104, Commander Gibson on SMS forward flight deck

NASA Image and Video Library

1988-02-03

STS-27 Atlantis, Orbiter Vehicle (OV) 104, Commander Robert L. Gibson, wearing flight coveralls and communications kit assembly, sits at commanders station controls on JSC shuttle mission simulator (SMS) forward flight deck during training session. Gibson looks at crewmember on aft flight deck. SMS is located in the Mission Simulation and Training Facility Bldg 5.
Design of a Controllable Weather Balloon to Fly on Mars

NASA Astrophysics Data System (ADS)

Ivie, Benjamin

As the National Aeronautics and Space Administration (NASA) moves closer towards placing humans on Mars, prediction of the weather on the planet becomes more vital to ensure the safety of the astronauts. Currently on Mars NASA has land based weather stations on the rovers and a few satellites orbiting the planet that help to predict the weather. They also use Earth based telescopes to look at the Martian atmosphere similar to what an orbiting satellite would [1]. These resources provide information about what the weather is like on the surface and what the weather looks like from space but there is little information from inside the atmosphere. Having a device that can fly through the atmosphere and collect data would enable scientists to generate more accurate models of the weather on Mars. Another use for these devices could be to get aerial photographs of the planet, which could help to determine possible sites for future exploration. Also the Martian air could be collected and analyzed to determine its composition and whether there could be any airborne signs of life. The research presented in this thesis is a first step towards designing a device to fly on Mars and take weather data. A lifting type is selected and through test flights on Earth the design is modified until a workable platform for flight testing is achieved. Once it is determined, the design is scaled to be able to fly in the Martian atmosphere.
Market Assessment of Forward-Looking Turbulence Sensing Systems

NASA Technical Reports Server (NTRS)

Kauffmann, Paul

2003-01-01

This viewgraph presentation provides a cost benefit analysis of three next-generation forward-looking turbulence sensing systems: X band turbulence radar system for convective turbulence, LIDAR based turbulence systems to sense clear air turbulence and a combined hybrid system. Parameters for the cost benefit analysis were established using a business model which considered injury rates, cost of injuries, indirect costs, market penetration rate estimates and product success characteristics. Topics covered include: study approach, business case equations, data acquisition, benchmark analysis. Data interpretation from the cost benefit analysis is presented. The researchers conclude that the market potential for these products is based primarily on injury cost reduction and that X band radar systems have the greatest chance for commercial success.
Potential risk of viral transmission from flying foxes to domestic animals and humans on the southern coast of West Java, Indonesia

PubMed Central

BASRI, Chaerul; ARIFIN, Eko Muhammad Zainal; TAKEMAE, Hitoshi; HENGJAN, Yupadee; IIDA, Keisuke; SUDARNIKA, Etih; ZAHID, Abdul; SOEJOEDONO, Retno Damayanti; SUSETYA, Heru; SUMIARTO, Bambang; KOBAYASHI, Ryosuke; AGUNGPRIYONO, Srihadi; HONDO, Eiichi

2017-01-01

Flying foxes have been considered to be involved in the transmission of serious infectious diseases to humans. Using questionnaires, we aimed to determine the direct and/or indirect contacts of flying foxes in an Indonesian nature conservation area with domestic animals and humans living in the surrounding area. We surveyed 150 residents of 10 villages in West Java. Villages were classified into 3 groups: inside and/or within 1 km from the outer border of the conservation area and 1–5 km or 5–10 km away from the reserve’s outer border. Data were collected by direct interview using a structured questionnaire consisting of the respondent characteristics (age, sex and occupation); histories of contacts between flying foxes and humans, dogs and other domestic animals; and knowledge about infectious diseases, mainly rabies, in flying foxes. We found that flying foxes from the nature conservation area often enter residential areas at night to look for food, especially during the fruit season. In these residential areas, flying foxes had direct contacts with humans and a few contacts with domestic animals, especially dogs. People who encounter flying foxes seldom used personal protective equipment, such as leather gloves, goggles and caps. The residents living around the conservation area mostly had poor knowledge about flying foxes and disease transmission. This situation shows that the population in this region is at a quite high risk for contracting infectious diseases from flying foxes. PMID:28724851
Potential risk of viral transmission from flying foxes to domestic animals and humans on the southern coast of West Java, Indonesia.

PubMed

Basri, Chaerul; Arifin, Eko Muhammad Zainal; Takemae, Hitoshi; Hengjan, Yupadee; Iida, Keisuke; Sudarnika, Etih; Zahid, Abdul; Soejoedono, Retno Damayanti; Susetya, Heru; Sumiarto, Bambang; Kobayashi, Ryosuke; Agungpriyono, Srihadi; Hondo, Eiichi

2017-09-29

Flying foxes have been considered to be involved in the transmission of serious infectious diseases to humans. Using questionnaires, we aimed to determine the direct and/or indirect contacts of flying foxes in an Indonesian nature conservation area with domestic animals and humans living in the surrounding area. We surveyed 150 residents of 10 villages in West Java. Villages were classified into 3 groups: inside and/or within 1 km from the outer border of the conservation area and 1-5 km or 5-10 km away from the reserve's outer border. Data were collected by direct interview using a structured questionnaire consisting of the respondent characteristics (age, sex and occupation); histories of contacts between flying foxes and humans, dogs and other domestic animals; and knowledge about infectious diseases, mainly rabies, in flying foxes. We found that flying foxes from the nature conservation area often enter residential areas at night to look for food, especially during the fruit season. In these residential areas, flying foxes had direct contacts with humans and a few contacts with domestic animals, especially dogs. People who encounter flying foxes seldom used personal protective equipment, such as leather gloves, goggles and caps. The residents living around the conservation area mostly had poor knowledge about flying foxes and disease transmission. This situation shows that the population in this region is at a quite high risk for contracting infectious diseases from flying foxes.
52. (Credit JTL) Interior view looking west at the two ...

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

52. (Credit JTL) Interior view looking west at the two crank-and-fly wheel high service engines. Steam cylinders of engines are to the left; water pumps and condensers to the right. The Worthington-Snow engine in the foreground was built with 18"x36" and 40"x36" cylinders; its pumps can deliver 5 mgd total from two 15" diameter plungers. - McNeil Street Pumping Station, McNeil Street & Cross Bayou, Shreveport, Caddo Parish, LA
On JALT 95: Curriculum and Evaluation. Proceedings of the JALT International Conference on Language Teaching/Learning (22nd, Nagoya, Japan, November 1995).

ERIC Educational Resources Information Center

Troyer, Gene van, Ed.; And Others

The conference proceedings include 62 papers on aspects of language teaching and learning, organized in seven sections: looking back, looking forward (history of language teaching, future directions); curriculum design (curriculum development, competency-based curricula, content-based instruction, global issues in curriculum and evaluation,…
Looking Back, Looking Forward: Tracing the Arc of Early Childhood Policy

ERIC Educational Resources Information Center

Connors-Tadros, Lori; Gardner, Madelyn

2018-01-01

The National Association of State Boards of Education (NASBE) convened its Task Force on Early Childhood Education in the larger context of educational reform of the 1980s, which was characterized by two competing perspectives. One focused on state-mandated testing and increased graduation requirements, in response to the alarm sounded by the…
ALICE and "The state of matter" at LHC

ScienceCinema

Schukraft, Juergen

2018-04-26

Assembly and installation of ALICE, the LHC heavy ion experiment dedicated to the study of matter at extreme temperature and pressure, is nearing completion and the commissioning of the detector is well under way. A good time to look back, to the making of ALICE, and to look forward, to the first physics with proton and heavy ion beams.
Looking Back, Looking Forward: The Past 15 Years of Mathematics Education in "CJSTME"

ERIC Educational Resources Information Center

Hare, Andrew; Ng, Oi-Lam

2015-01-01

In this article, we review the publications served by the "Canadian Journal of Science, Mathematics and Technology Education" in the past 15 years, specific to the field of mathematics education, and make connections with development of the field. In particular, we adopt current Editor-in-Chief John Wallace's (2009) approach of…
Sociocultural Theories of Learning and Motivation: Looking Back, Looking Forward. Research on Sociocultural Influences on Motivation and Learning

ERIC Educational Resources Information Center

McInerney, Dennis M., Ed.; Walker, Richard A., Ed.; Liem, Gregory Arief D., Ed.

2011-01-01

It is now nearly thirty years since sociocultural theories of learning created great excitement and debate amongst those concerned with learning in diverse contexts. Since that time significant advances have been made in sociocultural theory and research. Various sociocultural approaches to the understanding of learning (for example, sociocultural…
Arm-Locking with the GRACE Follow-On Laser Ranging Instrument

NASA Technical Reports Server (NTRS)

Thorpe, James Ira; Mckenzie, Kirk

2016-01-01

Arm-locking is a technique for stabilizing the frequency of a laser in an inter-spacecraft interferometer by using the spacecraft separation as the frequency reference. A candidate technique for future space-based gravitational wave detectors such as the Laser Interferometer Space Antenna (LISA), arm-locking has been extensive studied in this context through analytic models, time-domain simulations, and hardware-in-the-loop laboratory demonstrations. In this paper we show the Laser Ranging Instrument flying aboard the upcoming Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission provides an appropriate platform for an on-orbit demonstration of the arm-locking technique. We describe an arm-locking controller design for the GRACE-FO system and a series of time-domain simulations that demonstrate its feasibility. We conclude that it is possible to achieve laser frequency noise suppression of roughly two orders of magnitude around a Fourier frequency of 1Hz with conservative margins on the system's stability. We further demonstrate that `pulling' of the master laser frequency due to fluctuating Doppler shifts and lock acquisition transients is less than 100MHz over several GRACE-FO orbits. These findings motivate further study of the implementation of such a demonstration.
The Space Technology-7 Disturbance Reduction Systems

NASA Technical Reports Server (NTRS)

ODonnell, James R., Jr.; Hsu, Oscar C.; Hanson, John; Hruby, Vlad

2004-01-01

The Space Technology 7 Disturbance Reduction System (DRS) is an in-space technology demonstration designed to validate technologies that are required for future missions such as the Laser Interferometer Space Antenna (LISA) and the Micro-Arcsecond X-ray Imaging Mission (MAXIM). The primary sensors that will be used by DRS are two Gravitational Reference Sensors (GRSs) being developed by Stanford University. DRS will control the spacecraft so that it flies about one of the freely-floating Gravitational Reference Sensor test masses, keeping it centered within its housing. The other GRS serves as a cross-reference for the first as well as being used as a reference for .the spacecraft s attitude control. Colloidal MicroNewton Thrusters being developed by the Busek Co. will be used to control the spacecraft's position and attitude using a six degree-of-freedom Dynamic Control System being developed by Goddard Space Flight Center. A laser interferometer being built by the Jet Propulsion Laboratory will be used to help validate the results of the experiment. The DRS will be launched in 2008 on the European Space Agency (ESA) LISA Pathfinder spacecraft along with a similar ESA experiment, the LISA Test Package.
Systems level feasibility study for the detection of extra-solar planets. Volume 1: Infrared interferometer (IRIS) known as the Stanford Concept

NASA Technical Reports Server (NTRS)

1979-01-01

A sensor system for the direct detection of extrasolar planets from an Earth orbit is evaluated: a spinning, infrared interferometer (IRIS). It is shuttle deployed, free flying, requires no on-orbit assembly and no reservicing over a design life of five years. The sensor concept and the mission objectives are reviewed, and the performance characteristics of a baseline sensor for standard observation conditions are derived. A baseline sensor design is given and the enabling technology discussed. Cost and weight estimates are performed; and a schedule for an IRIS program including technology development and assessment of risk are given. Finally, the sensor is compared with the apodized visual telescope sensor (APOTS) proposed for the same mission. The major conclusions are: that with moderate to strong technology advances, particularly in the fields of long life cryogenics, dynamical control, mirror manufacturing, and optical alignment, the detection of a Jupiter like planet around a Sunlike star at a distance of 30 light years is feasible, with a 3 meter aperture and an observation time of 1 hour. By contrast, major and possibly unlikely breakthroughs in mirror technology are required for APOTS to match this performance.
Striving for work-life balance: effect of marriage and children on the experience of 4402 US general surgery residents.

PubMed

Sullivan, Michael C; Yeo, Heather; Roman, Sanziana A; Bell, Richard H; Sosa, Julie A

2013-03-01

To determine how marital status and having children impact US general surgical residents' attitudes toward training and personal life. There is a paucity of research describing how family and children affect the experience of general surgery residents. Cross-sectional survey involving all US categorical general surgery residents. Responses were evaluated by resident/program characteristics. Statistical analysis included the χ test and hierarchical logistic regression modeling. A total of 4402 residents were included (82.4% response rate) and categorized as married, single, or other (separated/divorced/widowed). Men were more likely to be married (57.8% vs 37.9%, P < 0.001) and have children (31.5% vs 12.0%, P < 0.001). Married residents were most likely to look forward to work (P < 0.001), and report happiness at work (P < 0.001) and a good program fit (P < 0.001). "Other" residents most frequently felt that work hours caused strain on family life (P < 0.001). Residents with children more frequently looked forward to work (P = 0.001), were happy at work (P = 0.001), and reported a good program fit (P = 0.034), but had strain on family life (P < 0.001), and worried about future finances (P = 0.005). On hierarchical logistic regression modeling, having children was predictive of a resident looking forward to work [odds ratio (OR): 1.22, P = 0.035], yet feeling that work caused family strain (OR: 1.66, P < 0.001); being single was associated with less strain (OR: 0.72, P < 0.001). The female gender was negatively associated with looking forward to work (OR: 0.81, P = 0.007). Residents who were married or parents reported greater satisfaction and work-life conflict. The complex effects of family on surgical residents should inform programs to target support mechanisms for their trainees.
Structure of the torque ring of the flagellar motor and the molecular basis for rotational switching.

PubMed

Lee, Lawrence K; Ginsburg, Michael A; Crovace, Claudia; Donohoe, Mhairi; Stock, Daniela

2010-08-19

The flagellar motor drives the rotation of flagellar filaments at hundreds of revolutions per second, efficiently propelling bacteria through viscous media. The motor uses the potential energy from an electrochemical gradient of cations across the cytoplasmic membrane to generate torque. A rapid switch from anticlockwise to clockwise rotation determines whether a bacterium runs smoothly forward or tumbles to change its trajectory. A protein called FliG forms a ring in the rotor of the flagellar motor that is involved in the generation of torque through an interaction with the cation-channel-forming stator subunit MotA. FliG has been suggested to adopt distinct conformations that induce switching but these structural changes and the molecular mechanism of switching are unknown. Here we report the molecular structure of the full-length FliG protein, identify conformational changes that are involved in rotational switching and uncover the structural basis for the formation of the FliG torque ring. This allows us to propose a model of the complete ring and switching mechanism in which conformational changes in FliG reverse the electrostatic charges involved in torque generation.

Time-Varying Expression of the Formation Flying along Circular Trajectories

NASA Technical Reports Server (NTRS)

Kawaguchi, Jun'ichiro

2007-01-01

Usually, the formation flying associated with circular orbits is discussed through the well-known Hill s or C-W equations of motion. This paper dares to present and discuss the coordinates that may contain time-varying coefficients. The discussion presents how the controller s performance is affected by the selection of coordinates, and also looks at the special coordinate suitable for designating a target bin to which each spacecraft in the formation has only to be guided. It is revealed that the latter strategy may incorporate the J2 disturbance automatically.
Moving Forward: U.S. Interest and Facilitating the Probable in Iraq

DTIC Science & Technology

2008-05-01

that will ultimately lead to independence in 1991. The Northern No-Fly Zone and the Green Line restricted Iraqi military movement. The Iraqi...John S. Survival among the Kurds: A History of the Yezidis, rev ed. New York, NY: Kegan Paul International, 1993. Gunter, Michael M. The Kurds and
Lame Ducks Can Leave on Wings that Fly.

ERIC Educational Resources Information Center

Richter, Richard P.

1995-01-01

While a "lame duck" college president may have diminished authority, he may also enjoy an unusual opportunity to move the institution forward. Outgoing presidents who pursue a substantive agenda during their final months can calm fears and second-guessing, preserve institutional momentum, and conclude their term with the satisfaction of a job well…
Mechanical and Durability Properties of Fly Ash Based Concrete Exposed to Marine Environment

NASA Astrophysics Data System (ADS)

Kagadgar, Sarfaraz Ahmed; Saha, Suman; Rajasekaran, C.

2017-06-01

Efforts over the past few years for improving the performance of concrete suggest that cement replacement with mineral admixtures can enhance the strength and durability of concrete. Feasibility of producing good quality concrete by using alccofine and fly ash replacements is investigated and also the potential benefits from their incorporation were looked into. In this study, an attempt has been made to assess the performance of concrete in severe marine conditions exposed upto a period of 150 days. This work investigates the influence of alccofine and fly ash as partial replacement of cement in various percentages (Alccofine - 5% replacement to cement content) and (fly ash - 0%, 15%, 30%, 50% & 60% to total cementitious content) on mechanical and durability properties (Permit ion permeability test and corrosion current density) of concrete. Usage of alccofine and high quantity of fly ash as additional cementitious materials in concrete has resulted in higher workability of concrete. Inclusion of alccofine shows an early strength gaining property whereas fly ash results in gaining strength at later stage. Concrete mixes containing 5% alccofine with 15% fly ash replacement reported greater compressive strength than the other concrete mixes cured in both curing conditions. Durability test conducted at 56 and 150 days indicated that concrete containing higher percentages of fly ash resulted in lower permeability as well lesser corrosion density.
A Nanny Versus Daycare: Is There a Right Choice?

PubMed

Kimball, Valerie

2016-02-01

As spring is on the horizon, my children begin to anticipate the end of the school year with thoughts of sleeping in, free days at the pool, and long evenings outside with friends. I, too, look forward to this time of the year, and a much needed hiatus from coaxing kids out of bed, making school lunches, and homework help in the evenings. However, I do not look forward to finding a new "kid sitter" for my preteens and teenager. Choice of childcare is perceived as perhaps one of the most stressful decisions parents must make for their children. Pediatic caregivers should discuss childcare as early as the prenatal visit and at all well visits thereafter. Copyright 2016, SLACK Incorporated.
Sequential feature selection for detecting buried objects using forward looking ground penetrating radar

NASA Astrophysics Data System (ADS)

Shaw, Darren; Stone, Kevin; Ho, K. C.; Keller, James M.; Luke, Robert H.; Burns, Brian P.

2016-05-01

Forward looking ground penetrating radar (FLGPR) has the benefit of detecting objects at a significant standoff distance. The FLGPR signal is radiated over a large surface area and the radar signal return is often weak. Improving detection, especially for buried in road targets, while maintaining an acceptable false alarm rate remains to be a challenging task. Various kinds of features have been developed over the years to increase the FLGPR detection performance. This paper focuses on investigating the use of as many features as possible for detecting buried targets and uses the sequential feature selection technique to automatically choose the features that contribute most for improving performance. Experimental results using data collected at a government test site are presented.
Terrestrial Planet Finder: Coda to 10 Years of Technology Development

NASA Technical Reports Server (NTRS)

Lawson, Peter R.

2009-01-01

The Terrestrial Planet Finder (TPF) was proposed as a mission concept to the 2000 Decadal Survey, and received a very high ranking amongst the major initiatives that were then reviewed. As proposed, it was a formation flying array of four 3-m class mid-infrared telescopes, linked together as an interferometer. Its science goal was to survey 150 nearby stars for the presence of Earth-like planets, to detect signs of life or habitability, and to enable revolutionary advances in high angular resolution astrophysics. The Decadal Survey Committee recommended that $200M be invested to advance TPF technology development in the Decade of 2000-2010. This paper presents the results of NASA's investment.
sTools - a data reduction pipeline for the GREGOR Fabry-Pérot Interferometer and the High-resolution Fast Imager at the GREGOR solar telescope

NASA Astrophysics Data System (ADS)

Kuckein, C.; Denker, C.; Verma, M.; Balthasar, H.; González Manrique, S. J.; Louis, R. E.; Diercke, A.

2017-10-01

A huge amount of data has been acquired with the GREGOR Fabry-Pérot Interferometer (GFPI), large-format facility cameras, and since 2016 with the High-resolution Fast Imager (HiFI). These data are processed in standardized procedures with the aim of providing science-ready data for the solar physics community. For this purpose, we have developed a user-friendly data reduction pipeline called ``sTools'' based on the Interactive Data Language (IDL) and licensed under creative commons license. The pipeline delivers reduced and image-reconstructed data with a minimum of user interaction. Furthermore, quick-look data are generated as well as a webpage with an overview of the observations and their statistics. All the processed data are stored online at the GREGOR GFPI and HiFI data archive of the Leibniz Institute for Astrophysics Potsdam (AIP). The principles of the pipeline are presented together with selected high-resolution spectral scans and images processed with sTools.
Aerodynamic evaluation of wing shape and wing orientation in four butterfly species using numerical simulations and a low-speed wind tunnel, and its implications for the design of flying micro-robots.

PubMed

Ortega Ancel, Alejandro; Eastwood, Rodney; Vogt, Daniel; Ithier, Carter; Smith, Michael; Wood, Rob; Kovač, Mirko

2017-02-06

Many insects are well adapted to long-distance migration despite the larger energetic costs of flight for small body sizes. To optimize wing design for next-generation flying micro-robots, we analyse butterfly wing shapes and wing orientations at full scale using numerical simulations and in a low-speed wind tunnel at 2, 3.5 and 5 m s -1 . The results indicate that wing orientations which maximize wing span lead to the highest glide performance, with lift to drag ratios up to 6.28, while spreading the fore-wings forward can increase the maximum lift produced and thus improve versatility. We discuss the implications for flying micro-robots and how the results assist in understanding the behaviour of the butterfly species tested.
Aerodynamic evaluation of wing shape and wing orientation in four butterfly species using numerical simulations and a low-speed wind tunnel, and its implications for the design of flying micro-robots

PubMed Central

Eastwood, Rodney; Vogt, Daniel; Ithier, Carter; Smith, Michael; Wood, Rob; Kovač, Mirko

2017-01-01

Many insects are well adapted to long-distance migration despite the larger energetic costs of flight for small body sizes. To optimize wing design for next-generation flying micro-robots, we analyse butterfly wing shapes and wing orientations at full scale using numerical simulations and in a low-speed wind tunnel at 2, 3.5 and 5 m s−1. The results indicate that wing orientations which maximize wing span lead to the highest glide performance, with lift to drag ratios up to 6.28, while spreading the fore-wings forward can increase the maximum lift produced and thus improve versatility. We discuss the implications for flying micro-robots and how the results assist in understanding the behaviour of the butterfly species tested. PMID:28163879
Distance underestimation in virtual space is sensitive to gender but not activity-passivity or mode of interaction.

PubMed

Foreman, Nigel; Sandamas, George; Newson, David

2004-08-01

Four groups of undergraduates (half of each gender) experienced a movement along a corridor containing three distinctive objects, in a virtual environment (VE) with wide-screen projection. One group simulated walking along the virtual corridor using a proprietary step-exercise device. A second group moved along the corridor in conventional flying mode, depressing a keyboard key to initiate continuous forward motion. Two further groups observed the walking and flying participants, by viewing their progress on the screen. Participants then had to walk along a real equivalent but empty corridor, and indicate the positions of the three objects. All groups underestimated distances in the real corridor, the greatest underestimates occurring for the middle distance object. Males' underestimations were significantly lower than females' at all distances. However, there was no difference between the active participants and passive observers, nor between walking and flying conditions.
Reading Recovery 20 Years down the Track: Looking Forward, Looking Back

ERIC Educational Resources Information Center

Reynolds, Meree; Wheldall, Kevin

2007-01-01

Reading Recovery is an intensive literacy programme designed for young students who have been identified as being at-risk of reading failure after 1 year of schooling. The intervention was developed and trialled in New Zealand over 20 years ago and is now implemented in a number of education systems. The focus of this article is on recent research…
Looking Forward, Looking Back: Framing the Future for Teaching for Social Justice in Early Childhood Education

ERIC Educational Resources Information Center

Hawkins, Karen

2014-01-01

There is little doubt that throughout the preschool years children are not only becoming more aware of themselves and their surroundings but they are also developing their moral frameworks by absorbing the attitudes and values of their family, culture and society. Undeniably the preschool years are crucial in shaping cultural and racial…
Perspectives on the Contribution of Social Science to Adapted Physical Activity: Looking Forward, Looking Back

ERIC Educational Resources Information Center

Causgrove Dunn, Janice; Cairney, John; Zimmer, Chantelle

2016-01-01

In this article, we reflect on the contributions of the social sciences to the field of adapted physical activity by examining the theories and methods that have been adopted from the social science disciplines. To broaden our perspective on adapted physical activity and provide new avenues for theoretical and empirical exploration, we discuss and…
Education for Sustainability--Looking Backward and Looking Forward--IUCN CEC Perspective on the United Nations Decade of ESD

ERIC Educational Resources Information Center

Wheeler, Keith A.; Hesselink, Frits; Goldstein, Wendy

2015-01-01

A network of volunteers, the International Union for Conservation of Nature Commission on Education and Communication (CEC), present some reflections on their contributions towards the field of education for sustainability from 1992 to the present. Many CEC members have been thought leaders to this multidimensional field, and advocates for a more…
Reflecting on the Present and Looking Ahead: A Response to Shuler

ERIC Educational Resources Information Center

Tobias, Evan S.

2014-01-01

In considering how policy work might forward arts education, it is helpful to reflect on the present state of music and arts education while looking ahead at future challenges and possibilities. This response to Shuler's (2001) set of predictions related to music education and policy in the twenty-first century addresses such work in the…
Looking Backward, Looking Forward: Forty Years of US Human Spaceflight Symposium

NASA Technical Reports Server (NTRS)

Garber, Stephen J. (Editor); Launius, Roger (Technical Monitor)

2001-01-01

This symposium reflects on forty years of U.S. Human Spaceflight, its role over the next four decades and beyond. The topics include: 1) Perspectives on the Past Forty Years of Human Spaceflight; 2) The Experience of Spaceflight; 3) Perspectives on the Next Forty Years of Human Spaceflight; and 4) The International Space Station and the Future of Human Spaceflight.
Looking Backward to Look Forward: Reflections of Past Presidents of the Council for Learning Disabilities

ERIC Educational Resources Information Center

Poch, Apryl L.

2018-01-01

Anniversaries offer a time for reflection, celebration, validation, and sometimes, simply a candid conversation on the current state of a field. In the field of learning disabilities, anniversaries offer a time to consider how far the field has come and just how far is left to go to understand what a learning disability is. Definitional…
Looking Back, Looking Forward, Living in the Moment: Understanding the Individual Temporal Perspectives of Secondary School EFL Learners

ERIC Educational Resources Information Center

Begic, Ines; Mercer, Sarah

2017-01-01

Every individual has a different perspective on time, known as "temporal perspective". A person's orientation and attitude towards time can have a profound effect on their behaviour and motivation. In Second Language Acquisition, a variety of work has considered learners and their behaviours from various temporal perspectives. However,…
Misrepresenting Religious Education's Past and Present in Looking Forward: Gearon Using Kuhn's Concepts of Paradigm, Paradigm Shift and Incommensurability

ERIC Educational Resources Information Center

Jackson, Robert

2015-01-01

In looking to the future, some writers on religious education (RE) have attempted to evaluate current approaches to the subject. Some have characterised any significant change in approach as a "paradigm shift", a term derived from Thomas Kuhn's work in the philosophy of science. This article examines the uses of the terms…

Looking Back and Looking Forward: A Glimpse of Blended Learning in Higher Education from 2007-2017

ERIC Educational Resources Information Center

Taylor, Maurice; Vaughan, Norman; Ghani, Shehzad K.; Atas, Sait; Fairbrother, Michael

2018-01-01

Using an engagement in research approach this article explores the landscape of blended learning in higher education over the last decade by comparing the results of a critical literature review by Vaughan to an instrumental case study that identified key factors that led to the implementation of a blended learning initiative in one medium sized…
Research traditions and evolutionary explanations in medicine.

PubMed

Méthot, Pierre-Olivier

2011-02-01

In this article, I argue that distinguishing 'evolutionary' from 'Darwinian' medicine will help us assess the variety of roles that evolutionary explanations can play in a number of medical contexts. Because the boundaries of evolutionary and Darwinian medicine overlap to some extent, however, they are best described as distinct 'research traditions' rather than as competing paradigms. But while evolutionary medicine does not stand out as a new scientific field of its own, Darwinian medicine is united by a number of distinctive theoretical and methodological claims. For example, evolutionary medicine and Darwinian medicine can be distinguished with respect to the styles of evolutionary explanations they employ. While the former primarily involves 'forward looking' explanations, the latter depends mostly on 'backward looking' explanations. A forward looking explanation tries to predict the effects of ongoing evolutionary processes on human health and disease in contemporary environments (e.g., hospitals). In contrast, a backward looking explanation typically applies evolutionary principles from the vantage point of humans' distant biological past in order to assess present states of health and disease. Both approaches, however, are concerned with the prevention and control of human diseases. In conclusion, I raise some concerns about the claim that 'nothing in medicine makes sense except in the light of evolution'.
Linear optical quantum metrology with single photons: exploiting spontaneously generated entanglement to beat the shot-noise limit.

PubMed

Motes, Keith R; Olson, Jonathan P; Rabeaux, Evan J; Dowling, Jonathan P; Olson, S Jay; Rohde, Peter P

2015-05-01

Quantum number-path entanglement is a resource for supersensitive quantum metrology and in particular provides for sub-shot-noise or even Heisenberg-limited sensitivity. However, such number-path entanglement has been thought to be resource intensive to create in the first place--typically requiring either very strong nonlinearities, or nondeterministic preparation schemes with feedforward, which are difficult to implement. Very recently, arising from the study of quantum random walks with multiphoton walkers, as well as the study of the computational complexity of passive linear optical interferometers fed with single-photon inputs, it has been shown that such passive linear optical devices generate a superexponentially large amount of number-path entanglement. A logical question to ask is whether this entanglement may be exploited for quantum metrology. We answer that question here in the affirmative by showing that a simple, passive, linear-optical interferometer--fed with only uncorrelated, single-photon inputs, coupled with simple, single-mode, disjoint photodetection--is capable of significantly beating the shot-noise limit. Our result implies a pathway forward to practical quantum metrology with readily available technology.
Envisioning New Technologies in Teacher Practice: Moving Forward, Circling Back Using a Teacher Action Research Approach. New Literacies and Digital Epistemologies. Volume 47

ERIC Educational Resources Information Center

Strong-Wilson, Teresa, Ed.

2012-01-01

How do classroom teachers envision new technologies within their practice? In the conversation on incorporating new technologies into classrooms, teachers are often sidelined. "Envisioning New Technologies in Teacher Practice" looks at the complex ways in which teachers move forward to embrace change as well as how they circle back, continually…
View of the forward fuselage and the reinforced carboncarbon nose ...

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

View of the forward fuselage and the reinforced carbon-carbon nose of the Orbiter Discovery looking aft while mounted atop the 76-wheeled orbiter transfer system as it is being rolled from the Orbiter Processing Facility to the Vehicle Assembly Building at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Looking Forward--Strategies for Inclusivity

ERIC Educational Resources Information Center

Eddy, Pamela L.

2017-01-01

This final chapter draws together the ways in which intersectionality occurs for a range of stakeholders regarding constructions of gender in community colleges and provides tactics for increasing equity.
Infrared atmospheric sounding interferometer correlation interferometry for the retrieval of atmospheric gases: the case of H2O and CO2.

PubMed

Grieco, Giuseppe; Masiello, Guido; Serio, Carmine; Jones, Roderic L; Mead, Mohammed I

2011-08-01

Correlation interferometry is a particular application of Fourier transform spectroscopy with partially scanned interferograms. Basically, it is a technique to obtain the difference between the spectra of atmospheric radiance at two diverse spectral resolutions. Although the technique could be exploited to design an appropriate correlation interferometer, in this paper we are concerned with the analytical aspects of the method and its application to high-spectral-resolution infrared observations in order to separate the emission of a given atmospheric gas from a spectral signal dominated by surface emission, such as in the case of satellite spectrometers operated in the nadir looking mode. The tool will be used to address some basic questions concerning the vertical spatial resolution of H2O and to develop an algorithm to retrieve the columnar amount of CO2. An application to complete interferograms from the Infrared Atmospheric Sounding Interferometer will be presented and discussed. For H2O, we have concluded that the vertical spatial resolution in the lower troposphere mostly depends on broad features associated with the spectrum, whereas for CO2, we have derived a technique capable of retrieving a CO2 columnar amount with accuracy of ≈±7 parts per million by volume at the level of each single field of view.
Curiosity: the Mars Science Laboratory Project

NASA Technical Reports Server (NTRS)

Cook, Richard A.

2012-01-01

The Curiosity rover landed successfully in Gale Crater, Mars on August 5, 2012. This event was a dramatic high point in the decade long effort to design, build, test and fly the most sophisticated scientific vehicle ever sent to Mars. The real achievements of the mission have only just begun, however, as Curiosity is now searching for signs that Mars once possessed habitable environments. The Mars Science Laboratory Project has been one of the most ambitious and challenging planetary projects that NASA has undertaken. It started in the successful aftermath of the 2003 Mars Exploration Rover project and was designed to take significant steps forward in both engineering and scientific capabilities. This included a new landing system capable of emplacing a large mobile vehicle over a wide range of potential landing sites, advanced sample acquisition and handling capabilities that can retrieve samples from both rocks and soil, and a high reliability avionics suite that is designed to permit long duration surface operations. It also includes a set of ten sophisticated scientific instruments that will investigate both the geological context of the landing site plus analyze samples to understand the chemical & organic composition of rocks & soil found there. The Gale Crater site has been specifically selected as a promising location where ancient habitable environments may have existed and for which evidence may be preserved. Curiosity will spend a minimum of one Mars year (about two Earth years) looking for this evidence. This paper will report on the progress of the mission over the first few months of surface operations, plus look retrospectively at lessons learned during both the development and cruise operations phase of the mission..
In-Space Inspection Technologies Vision

NASA Technical Reports Server (NTRS)

Studor, George

2012-01-01

Purpose: Assess In-Space NDE technologies and needs - current & future spacecraft. Discover & build on needs, R&D & NDE products in other industries and agencies. Stimulate partnerships in & outside NASA to move technologies forward cooperatively. Facilitate group discussion on challenges and opportunities of mutual benefit. Focus Areas: Miniaturized 3D Penetrating Imagers Controllable Snake-arm Inspection systems Miniature Free-flying Micro-satellite Inspectors
Large-scale production of megakaryocytes from human pluripotent stem cells by chemically defined forward programming

PubMed Central

Moreau, Thomas; Evans, Amanda L.; Vasquez, Louella; Tijssen, Marloes R.; Yan, Ying; Trotter, Matthew W.; Howard, Daniel; Colzani, Maria; Arumugam, Meera; Wu, Wing Han; Dalby, Amanda; Lampela, Riina; Bouet, Guenaelle; Hobbs, Catherine M.; Pask, Dean C.; Payne, Holly; Ponomaryov, Tatyana; Brill, Alexander; Soranzo, Nicole; Ouwehand, Willem H.; Pedersen, Roger A.; Ghevaert, Cedric

2016-01-01

The production of megakaryocytes (MKs)—the precursors of blood platelets—from human pluripotent stem cells (hPSCs) offers exciting clinical opportunities for transfusion medicine. Here we describe an original approach for the large-scale generation of MKs in chemically defined conditions using a forward programming strategy relying on the concurrent exogenous expression of three transcription factors: GATA1, FLI1 and TAL1. The forward programmed MKs proliferate and differentiate in culture for several months with MK purity over 90% reaching up to 2 × 105 mature MKs per input hPSC. Functional platelets are generated throughout the culture allowing the prospective collection of several transfusion units from as few as 1 million starting hPSCs. The high cell purity and yield achieved by MK forward programming, combined with efficient cryopreservation and good manufacturing practice (GMP)-compatible culture, make this approach eminently suitable to both in vitro production of platelets for transfusion and basic research in MK and platelet biology. PMID:27052461
Large-scale production of megakaryocytes from human pluripotent stem cells by chemically defined forward programming.

PubMed

Moreau, Thomas; Evans, Amanda L; Vasquez, Louella; Tijssen, Marloes R; Yan, Ying; Trotter, Matthew W; Howard, Daniel; Colzani, Maria; Arumugam, Meera; Wu, Wing Han; Dalby, Amanda; Lampela, Riina; Bouet, Guenaelle; Hobbs, Catherine M; Pask, Dean C; Payne, Holly; Ponomaryov, Tatyana; Brill, Alexander; Soranzo, Nicole; Ouwehand, Willem H; Pedersen, Roger A; Ghevaert, Cedric

2016-04-07

The production of megakaryocytes (MKs)--the precursors of blood platelets--from human pluripotent stem cells (hPSCs) offers exciting clinical opportunities for transfusion medicine. Here we describe an original approach for the large-scale generation of MKs in chemically defined conditions using a forward programming strategy relying on the concurrent exogenous expression of three transcription factors: GATA1, FLI1 and TAL1. The forward programmed MKs proliferate and differentiate in culture for several months with MK purity over 90% reaching up to 2 × 10(5) mature MKs per input hPSC. Functional platelets are generated throughout the culture allowing the prospective collection of several transfusion units from as few as 1 million starting hPSCs. The high cell purity and yield achieved by MK forward programming, combined with efficient cryopreservation and good manufacturing practice (GMP)-compatible culture, make this approach eminently suitable to both in vitro production of platelets for transfusion and basic research in MK and platelet biology.
Levers for Change in Educational Development in Canada: Looking Back, Looking Forward

ERIC Educational Resources Information Center

Dawson, Debra L.

2017-01-01

This paper examines levers or drivers that have influenced the direction of educational development in Canada over the last 40 years and also tries to predict what will be the impact of some current levers on changing the work of developers in the next 20 years. Reflecting on those years, it is apparent our work in the 1980s was very focused on…
Editorial: Biotechnology Journal 10 year Anniversary - Thank you for your continued support.

PubMed

Zhu, Jing

2015-12-01

When we came to realize that Biotechnology Journal is 10 years "old" and she is no longer "young", we started to look back and look forward again. We would like to thank all of the editors, authors, reviewers, readers and partners for your continued support during the past ten years! Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Looking Back, Looking Forward: How the Economic Downturn Continues to Impact School Districts. Report of Findings

ERIC Educational Resources Information Center

McCord, Robert S.; Ellerson, Noelle M.

2009-01-01

This study is the fourth in a series of studies conducted by the American Association of School Administrators on the impact of the economic downturn on schools. AASA launched the series in fall 2008 in response to state budget shortfalls, federal buy-outs and interventions, and a series of additional events characterizing a slowing, stagnant…
Looking Back, to Look Forward: Using Traditional Cultural Examples to Explain Contemporary Ideas in Technology Education

ERIC Educational Resources Information Center

Lee, Kerry

2011-01-01

Although the term "technology" means different things to different people, most would generally agree that it is about "stuff." For some it may be more complex than this, and for others it may simply involve using or studying high-tech gadgetry, such as computers and iPhones. Understanding the interdependence between design and culture is a…
27. VIEW LOOKING AFT ON STARBOARD SIDE OF MAIN DECK ...

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

27. VIEW LOOKING AFT ON STARBOARD SIDE OF MAIN DECK WITH TENDER ANNIE RUTH ALONGSIDE. COVER OF FORWARD COMPANIONWAY HAS BEEN PLACED ON MAIN DECK; SUN AWNING A TYPICAL FEATURE IN TROPICAL CLIMATES. CREW MEMBERS UNKNOWN Original 4-3/4'x6-3/4' photograph taken c. 1930? - Pilot Schooner "Alabama", Moored in harbor at Vineyard Haven, Vineyard Haven, Dukes County, MA
Internet platforms for lifelong learning: a continuum of opportunity.

PubMed

Sedory Holzer, Susan E; Kokemueller, Phillip

2007-12-01

Access to knowledge through the Internet has spawned a world of online learning, stimulating a new passion for lifelong learning in academia, professional environments, the workplace, and at home. This article takes a fresh look at the wide spectrum of opportunities for online medical education for physicians. We first explore a continuum of "e-learning" models and then look at the range of platforms used to support these systems. We will also look forward to the options likely to change e-learning in the near future and improve physician performance and patient outcomes.
The contribution of Medical Physics to Nuclear Medicine: looking back - a physicist's perspective.

PubMed

Hutton, Brian F

2014-12-01

This paper is the first in a series of invited perspectives by four pioneers of Nuclear Medicine imaging and physics. A medical physicist and a Nuclear Medicine clinical specialist each take a backward look and a forward look at the contributions of Medical Physics to Nuclear Medicine. Contributions of Medical Physics are presented from the early discovery of radioactivity, development of first imaging devices, computers and emission tomography to recent development of hybrid imaging. There is evidence of significant contribution of Medical Physics throughout the development of Nuclear Medicine.
The Dragon Enters Africa

DTIC Science & Technology

2011-05-04

Nations General Assembly. China looks to secure the support and votes of these African states to help influence international politics moving forward. 1S...support and votes of th~se African states to help influence international politics moving forward. . . Conclusion: China’s declaration of their... international focus with the recognition of a new advei·sary. The attack on the World Trade Center brought telTorism to the forefront of the natiohal security
Fish-eye view of STS-112 CDR Ashby on forward flight deck

NASA Image and Video Library

2002-10-18

STS112-347-001 (18 October 2002) --- A fish-eye lens on a 35mm camera records astronaut Jeffrey S. Ashby, STS-112 mission commander, at the commanders station on the forward flight deck of the Space Shuttle Atlantis. Ashby, attired in his shuttle launch and entry suit, looks over a checklist prior to the entry phase of the flight.

Developing a novel UAV (Unmanned Aerial Vehicle) helicopter platform for very high resolution environmental monitoring of catchment processes

NASA Astrophysics Data System (ADS)

Freer, J. E.; Richardson, T.; Yang, Z.

2012-12-01

Recent advances in remote sensing and geographic information has led the way for the development of hyperspectral sensors and cloud scanning LIDAR (Light Detection And Ranging). Both these technologies can be used to sense environmental processes and capture detailed spatial information, they are often deployed in ground, aircraft and satellite based systems. Hyperspectral remote sensing, also known as imaging spectroscopy, is a relatively new technology that is currently being investigated by researchers and scientists with regard to the detection and identification of landscapes, terrestrial vegetation, and manmade materials and backgrounds. There are many applications that could take advantages of hyperspectral remote sensing coupled to detailed surface feature mapping using LIDAR. This embryonic project involves developing the engineering solutions and post processing techniques needed to realise an ultra high resolution helicopter based environmental sensing platform which can fly at lower altitudes than aircraft systems and can be deployed more frequently. We aim to present this new technology platform in this special session (the only one of it's kind in the UK). Initial applications are planned on a range of environmental sensing problems that would benefit from such complex and detailed data.We look forward to being able to display and discuss this initiative with colleagues and any potential interest in future collaborative projects.
Developing a novel UAV (Unmanned Aerial Vehicle) helicopter platform for very high resolution environmental monitoring of catchment processes

NASA Astrophysics Data System (ADS)

Freer, J.; Richardson, T. S.

2012-04-01

Recent advances in remote sensing and geographic information has led the way for the development of hyperspectral sensors and cloud scanning LIDAR (Light Detection And Ranging). Both these technologies can be used to sense environmental processes and capture detailed spatial information, they are often deployed in ground, aircraft and satellite based systems. Hyperspectral remote sensing, also known as imaging spectroscopy, is a relatively new technology that is currently being investigated by researchers and scientists with regard to the detection and identification of landscapes, terrestrial vegetation, and manmade materials and backgrounds. There are many applications that could take advantages of hyperspectral remote sensing coupled to detailed surface feature mapping using LIDAR. This embryonic project involves developing the engineering solutions and post processing techniques needed to realise an ultra high resolution helicopter based environmental sensing platform which can fly at lower altitudes than aircraft systems and can be deployed more frequently. We aim to display this new technology platform in this special session (the only one of it's kind in the UK). Initial applications are planned on a range of environmental sensing problems that would benefit from such complex and detailed data. We look forward to being able to display and discuss this initiative with colleagues and any potential interest in future collaborative projects.
Real-time Enhancement, Registration, and Fusion for an Enhanced Vision System

NASA Technical Reports Server (NTRS)

Hines, Glenn D.; Rahman, Zia-ur; Jobson, Daniel J.; Woodell, Glenn A.

2006-01-01

Over the last few years NASA Langley Research Center (LaRC) has been developing an Enhanced Vision System (EVS) to aid pilots while flying in poor visibility conditions. The EVS captures imagery using two infrared video cameras. The cameras are placed in an enclosure that is mounted and flown forward-looking underneath the NASA LaRC ARIES 757 aircraft. The data streams from the cameras are processed in real-time and displayed on monitors on-board the aircraft. With proper processing the camera system can provide better-than-human-observed imagery particularly during poor visibility conditions. However, to obtain this goal requires several different stages of processing including enhancement, registration, and fusion, and specialized processing hardware for real-time performance. We are using a real-time implementation of the Retinex algorithm for image enhancement, affine transformations for registration, and weighted sums to perform fusion. All of the algorithms are executed on a single TI DM642 digital signal processor (DSP) clocked at 720 MHz. The image processing components were added to the EVS system, tested, and demonstrated during flight tests in August and September of 2005. In this paper we briefly discuss the EVS image processing hardware and algorithms. We then discuss implementation issues and show examples of the results obtained during flight tests.
Black Youth in Cuba

ERIC Educational Resources Information Center

Horne, Gerald C.

1975-01-01

Cuban social system has eliminated discrimination, racism, sexism and unemployment and created equal opportunity for all. Cuba is upheld as model for all forward looking U.S. citizens to study. (Author/AM)
Evolutionary technology adoption in an oligopoly market with forward-looking firms

NASA Astrophysics Data System (ADS)

Lamantia, F.; Radi, D.

2018-05-01

In this paper, we propose an evolutionary oligopoly game of technology adoption in a market with isoelastic demand and two possible (linear) production technologies. While one technology is characterized by lower marginal costs, the magnitude of fixed costs entails that a technology does not necessarily dominate the other. Firms are forward-looking as they assess the profitability of employing either technology according to the corresponding expected profits. The dynamics of the system is studied through a piecewise-smooth map, for which we present a local stability analysis of equilibria and show the occurrence of smooth and border collision bifurcations. Global analysis of the model is also presented to show the coexistence of attractors and its economic significance. This investigation reveals that firms can fail to learn to adopt the more efficient technology.
Evolutionary technology adoption in an oligopoly market with forward-looking firms.

PubMed

Lamantia, F; Radi, D

2018-05-01

In this paper, we propose an evolutionary oligopoly game of technology adoption in a market with isoelastic demand and two possible (linear) production technologies. While one technology is characterized by lower marginal costs, the magnitude of fixed costs entails that a technology does not necessarily dominate the other. Firms are forward-looking as they assess the profitability of employing either technology according to the corresponding expected profits. The dynamics of the system is studied through a piecewise-smooth map, for which we present a local stability analysis of equilibria and show the occurrence of smooth and border collision bifurcations. Global analysis of the model is also presented to show the coexistence of attractors and its economic significance. This investigation reveals that firms can fail to learn to adopt the more efficient technology.
Rosetta mission status: challenges of flying near a comet

NASA Astrophysics Data System (ADS)

Martin, P.; Taylor, M.; Kueppers, M.; O'Rourke, L.; Lodiot, S.

2015-10-01

Recent operational events, most likely due to the increased presence of dust near the spacecraft during close flybys of C67P/Churyumov-Gerasimenko in the comet escort phase, have led to a redefinition of the Rosetta mission through the design of new trajectories allowing the spacecraft and its payload to continue flying safely around the comet while augmenting the wealth of scientific data and results that has characterized the beginning of the mission so far. A decision process is being put in place in view of finding the best ways forward operationally so as to recover some capabilities that will allow Rosetta to continue optimising its scientific mission, in both the nominal and expected extended mission intervals.
Endeavour, OV-105, forward flight deck controls during Rockwell manufacture

NASA Technical Reports Server (NTRS)

1991-01-01

Endeavour, Orbiter Vehicle (OV) 105, forward flight deck controls are documented during manufacture, assembly, and checkout at North American Rockwell facilities Building 150, Palmdale, California. Overall view looks from aft flight deck forward showing displays and controls with panel F7 CRT screens lit and window shades in place on W2, W3, W4, W5. OV-105 is undergoing final touches prior to rollout and a scheduled flight for STS-49. View was included as part of Rockwell International (RI) Submittal No. 40 (STS 87-0342-40) with alternate number A901207 R-16/NAS9-17800.
KSC-2012-5023

NASA Image and Video Library

2012-09-12

CAPE CANAVERAL, Fla. - Henry Taylor, from left to right, chief flight engineer on the Shuttle Carrier Aircraft, or SCA, Gary Ash, flight engineer, and Jeff Moultrie, pilot, look ahead to flying space shuttle Endeavour from NASA's Kennedy Space Center in Florida to Los Angeles for public display. Photo credit: NASA/Kim Shiflett
Earth observation views taken during STS-106

NASA Image and Video Library

2000-09-10

S106-E-5074 (10 September 2000) --- This south-looking view from the Space Shuttle Atlantis, flying above Turkey, features the Mediterranean island of Cyprus. The photo was taken with an electronic still camera (ESC) on Flight Day 3 of the scheduled 11-day STS-106 mission.
Civil air transport: A fresh look at power-by-wire and fly-by-light

NASA Technical Reports Server (NTRS)

Sundberg, Gale R.

1990-01-01

Power-by-wire (PBW) is a key element under subsonic transport flight systems technology with potential savings of over 10 percent in gross take-off-weight and in fuel consumption compared to today's transport aircraft. The PBW technology substitutes electrical actuation in place of centralized hydraulics, uses internal starter-motor/generators and eliminates the need for variable engine bleed air to supply cabin comfort. The application of advanced fiber optics to the electrical power system controls, to built-in-test (BITE) equipment, and to fly-by-light (FBL) flight controls provides additional benefits in lightning and high energy radio frequency (HERF) immunity over existing mechanical or even fly-by-wire controls. The program plan is reviewed and a snapshot is given of the key technologies and their benefits to all future aircraft, both civil and military.
Civil air transport: A fresh look at power-by-wire and fly-by-light

NASA Technical Reports Server (NTRS)

Sundberg, Gale R.

1991-01-01

Power-by-wire (PBW) is a key element under subsonic transport flight systems technology with potential savings of over 10 percent in operating empty weight and in fuel consumption compared to today's transport aircraft. The PBW technology substitutes electrical actuation in place of centralized hydraulics, uses internal starter-motor/generators and eliminates the need for variable engine bleed air to supply cabin comfort. The application of advanced fiber optics to the electrical power system controls, to built-in-test (BIT) equipment, and to fly-by-light (FBL) flight controls provides additional benefits in lightning and high energy radio frequency (HERF) immunity over existing mechanical or even fly-by-wire controls. The program plan is reviewed and a snapshot is given of the key technologies and their benefits to all future aircraft, both civil and military.
On-the-Fly Kinetic Monte Carlo Simulation of Aqueous Phase Advanced Oxidation Processes.

PubMed

Guo, Xin; Minakata, Daisuke; Crittenden, John

2015-08-04

We have developed an on-the-fly kinetic Monte Carlo (KMC) model to predict the degradation mechanisms and fates of intermediates and byproducts that are produced during aqueous-phase advanced oxidation processes (AOPs). The on-the-fly KMC model is composed of a reaction pathway generator, a reaction rate constant estimator, a mechanistic reduction module, and a KMC solver. The novelty of this work is that we develop the pathway as we march forward in time rather than developing the pathway before we use the KMC method to solve the equations. As a result, we have fewer reactions to consider, and we have greater computational efficiency. We have verified this on-the-fly KMC model for the degradation of polyacrylamide (PAM) using UV light and titanium dioxide (i.e., UV/TiO2). Using the on-the-fly KMC model, we were able to predict the time-dependent profiles of the average molecular weight for PAM. The model provided detailed and quantitative insights into the time evolution of the molecular weight distribution and reaction mechanism. We also verified our on-the-fly KMC model for the destruction of (1) acetone, (2) trichloroethylene (TCE), and (3) polyethylene glycol (PEG) for the ultraviolet light and hydrogen peroxide AOP. We demonstrated that the on-the-fly KMC model can achieve the same accuracy as the computer-based first-principles KMC (CF-KMC) model, which has already been validated in our earlier work. The on-the-fly KMC is particularly suitable for molecules with large molecular weights (e.g., polymers) because the degradation mechanisms for large molecules can result in hundreds of thousands to even millions of reactions. The ordinary differential equations (ODEs) that describe the degradation pathways cannot be solved using traditional numerical methods, but the KMC can solve these equations.
Forward to the Future: Estimating River Discharge with McFLI

NASA Astrophysics Data System (ADS)

Gleason, C. J.; Durand, M. T.; Garambois, P. A.

2016-12-01

The global surface water budget is still poorly understood, and improving our understanding of freshwater budgets requires coordination between in situ observations, models, and remote sensing. The upcoming launch of the NASA/CNES Surface Water and Ocean Topography (SWOT) satellite has generated considerable excitement as a new tool enabling hydrologists to tackle some of the most pressing questions facing their discipline. One question in particular which SWOT seems well suited to answer is river discharge (flow rate) estimation in ungauged basins: SWOT's anticipated measurements of river surface height and area have ushered in a new technique in hydrology- what we are here calling Mass conserved Flow Law Inversions, or McFLI. McFLI algorithms leverage classic hydraulic flow expressions (e.g. Manning's Equation, hydraulic geometry) within mass conserved river reaches to construct a simplified but still underconstrained system of equations to be solved for an unknown discharge. Most existing McFLI techniques have been designed to take advantage of SWOT's measurements and Manning's Equation: SWOT will observe changes in cross sectional area and river surface slope over time, so the McFLI need only solve for baseflow area and Manning's roughness coefficient. Recently published preliminary results have indicated that McFLI can be a viable tool in a global hydrologist's toolbox (discharge errors less than 30% as compared to gauges are possible in most cases). Therefore, we here outline the progress to date for McFLI techniques, and highlight three key areas for future development: 1) Maximize the accuracy and robustness of McFLI by incorporating ancillary data from satellites, models, and in situ observations. 2) Develop new McFLI techniques using novel or underutilized flow laws. 3) Systematically test McFLI to define different inversion classes of rivers with well-defined error budgets based on geography and available data for use in gauged and ungauged basins alike.
The free-flight response of Drosophila to motion of the visual environment.

PubMed

Mronz, Markus; Lehmann, Fritz-Olaf

2008-07-01

In the present study we investigated the behavioural strategies with which freely flying fruit flies (Drosophila) control their flight trajectories during active optomotor stimulation in a free-flight arena. We measured forward, turning and climbing velocities of single flies using high-speed video analysis and estimated the output of a 'Hassenstein-Reichardt' elementary motion detector (EMD) array and the fly's gaze to evaluate flight behaviour in response to a rotating visual panorama. In a stationary visual environment, flight is characterized by flight saccades during which the animals turn on average 120 degrees within 130 ms. In a rotating environment, the fly's behaviour typically changes towards distinct, concentric circular flight paths where the radius of the paths increases with increasing arena velocity. The EMD simulation suggests that this behaviour is driven by a rotation-sensitive EMD detector system that minimizes retinal slip on each compound eye, whereas an expansion-sensitive EMD system with a laterally centred visual focus potentially helps to achieve centring response on the circular flight path. We developed a numerical model based on force balance between horizontal, vertical and lateral forces that allows predictions of flight path curvature at a given locomotor capacity of the fly. The model suggests that turning flight in Drosophila is constrained by the production of centripetal forces needed to avoid side-slip movements. At maximum horizontal velocity this force may account for up to 70% of the fly's body weight during yaw turning. Altogether, our analyses are widely consistent with previous studies on Drosophila free flight and those on the optomotor response under tethered flight conditions.
Early Rockets

NASA Image and Video Library

2004-04-15

According to one ancient legend, a Chinese official named Wan Hoo attempted a flight to the moon using a large wicker chair to which were fastened 47 large rockets. Forty seven assistants, each armed with a torch, rushed forward to light the fuses. In a moment, there was a tremendous roar accompanied by billowing clouds of smoke. When the smoke cleared, the flying chair and Wan Hoo were gone.
Body-freedom flutter of a 1/2-scale forward-swept-wing model, an experimental and analytical study

NASA Technical Reports Server (NTRS)

Chipman, R.; Rauch, F.; Rimer, M.; Muniz, B.

1984-01-01

The aeroelastic phenomenon known as body-freedom flutter (BFF), a dynamic instability involving aircraft-pitch and wing-bending motions which, though rarely experienced on conventional vehicles, is characteristic of forward swept wing (FSW) aircraft was investigated. Testing was conducted in the Langley transonic dynamics tunnel on a flying, cable-mounted, 1/2-scale model of a FSW configuration with and without relaxed static stability (RSS). The BFF instability boundaries were found to occur at significantly lower airspeeds than those associated with aeroelastic wing divergence on the same model. For those cases with RSS, a canard-based stability augmentation system (SAS) was incorporated in the model. This SAS was designed using aerodynamic data measured during a preliminary tunnel test in which the model was attached to a force balance. Data from the subsequent flutter test indicated that BFF speed was not dependent on open-loop static margin but, rather, on the equivalent closed-loop dynamics provided by the SAS. Servo-aeroelastic stability analyses of the flying model were performed using a computer code known as SEAL and predicted the onset of BFF reasonably well.
A high sensitivity heterodyne interferometer as a possible optical readout for the LISA gravitational reference sensor and its application to technology verification

NASA Astrophysics Data System (ADS)

Gohlke, Martin; Schuldt, Thilo; Weise, Dennis; Cordero, Jorge; Peters, Achim; Johann, Ulrich; Braxmaier, Claus

2017-11-01

The gravitational wave detector LISA utilizes as current baseline a high sensitivity Optical Readout (ORO) for measuring the relative position and tilt of a free flying proof mass with respect to the satellite housing. The required sensitivities in the frequency band from 30 μHz to 1Hz are ˜ pm/ √ Hz for the translation√ and nrad/√ Hz for the tilt measurement. EADS Astrium, in collaboration with the Humboldt University Berlin and the University of Applied Sciences Konstanz, has realized a prototype ORO over the past years. The interferometer is based on a highly symmetric design where both, measurement and reference beam have a similar optical pathlength, and the same frequency and polarization. The technique of differential wavefront sensing (DWS) for tilt measurement is implemented. With our setup noise levels below 5pm/ √Hz for translation and below 10nrad/ √Hz for tilt measurements - both for frequencies above 10mHz - were demonstrated. We give an overview over the experimental setup, its current performance and the planned improvements. We also discuss the application to first verification of critical LISA aspects. As example we present measurements of the coefficient of thermal expansion (CTE) of various carbon fiber reinforced plastic (CFRP) including a "near-zero-CTE" tube.
Final results of the PERSEE experiment

NASA Astrophysics Data System (ADS)

Le Duigou, J. M.; Lozi, J.; Cassaing, F.; Houairi, K.; Sorrente, B.; Montri, J.; Jacquinod, S.; Reess, J.-M.; Pham, L.; Lhome, E.; Buey, T.; Hénault, F.; Marcotto, A.; Girard, P.; Mauclert, N.; Barillot, M.; Coudé du Foresto, V.; Ollivier, M.

2012-07-01

The PERSEE breadboard, developed by a consortium including CNES, IAS, LESIA, OCA, ONERA and TAS since 2005, is a nulling demonstrator that couples an infrared nulling interferometer with a formation flying simulator able to introduce realistic disturbances in the set-up. The general idea is to prove that an adequate optical design can considerably relax the constraints applying at the spacecrafts level of a future interferometric space mission like Darwin/TPF or one of its precursors. The breadboard is now fully operational and the measurements sequences are managed from a remote control room using automatic procedures. A set of excellent results were obtained in 2011. The measured polychromatic nulling depth with non polarized light is 8.8 10-6 stabilized at 9 10-8 in the 1.65-2.45 μm spectral band (37 % bandwidth) during 100 s. This result was extended to a 7h duration thanks to an automatic calibration process. The various contributors are identified and the nulling budget is now well mastered. We also proved that harmonic disturbances in the 1-100 Hz up to several ten’s of nm rms can be very efficiently corrected by a Linear Quadratic Control (LQG) if a sufficient flux is available. These results are important contributions to the feasibility of a future space based nulling interferometer.
Final results of the PERSEE experiment

NASA Astrophysics Data System (ADS)

Le Duigou, J.-M.; Lozi, J.; Cassaing, F.; Houairi, K.; Sorrente, B.; Montri, J.; Jacquinod, S.; Réess, J.-M.; Pham, L.; Lhomé, E.; Buey, T.; Hénault, F.; Marcotto, A.; Girard, P.; Mauclert, N.; Barillot, M.; Coudé du Foresto, V.; Ollivier, M.

2017-11-01

The PERSEE breadboard, developed by a consortium including CNES, IAS, LESIA, OCA, ONERA and TAS since 2006, is a nulling demonstrator that couples an infrared nulling interferometer with a formation flying simulator able to introduce realistic disturbances in the set-up. The general idea is to prove that an adequate optical design can considerably release the constraints applied at the spacecrafts level of a future interferometric space mission like Darwin/TPF or one of its precursors. The breadboard is now fully operational and the measurements sequences are managed from a remote control room using automatic procedures. A set of excellent results were obtained in 2011: the measured polychromatic nulling depth with non polarized light is 8.8x10-6 stabilized at 9x10-8 in the [1.65-2.45] μm spectral band (37% bandwidth) during 100s. This result was extended to a 7h duration thanks to an automatic calibration process. The various contributors are identified and the nulling budget is now well mastered. We also proved that harmonic disturbances in the 1-100Hz up to several tens of nm rms can be very efficiently corrected by a Linear Quadratic Control (LQG) if a sufficient flux is available. These results are important contributions to the feasibility of a future space based nulling interferometer.

1986: A Big Year in Space.

ERIC Educational Resources Information Center

Haggerty, James J.

1985-01-01

Several major space programs in development for a decade or more will come to fruition in 1986. This illustrated summary amplifies several of these projects including: California space shuttle operations; fly-by Uranus; look at Comet Halley; space observatory; and others. Projects are significant in scientific potential and capability advancement.…
JPL HAMSR Takes Hurricane Matthew Temperature

NASA Image and Video Library

2016-10-07

JPL's High-Altitude Monolithic Microwave Integrated Circuit Sounding Radiometer (HAMSR) instrument captured this look inside Hurricane Matthew's spiral clouds on Oct. 7, 2016, flying on a NASA Global Hawk unmanned aircraft. Red colors show cloud bands without precipitation; blues show rain bands. http://photojournal.jpl.nasa.gov/catalog/PIA21093
Looking Backwards--Looking Forward. Volume V: July, 1989-June, 1990. A Collection of Essays: Recommendations Related to Education in General and Vocational-Technical Education in Particular.

ERIC Educational Resources Information Center

North Carolina State Advisory Council on Vocational Education, Raleigh.

This is the fifth of five volumes of essays in the form of recommendations for the improvement of programs, services, and activities offered through vocational-technical education in North Carolina. The volume explains the rationale for and comments on 15 recommendations prepared by the State Advisory Council on Vocational Education for fiscal…
General view of the flight deck of the Orbiter Discovery ...

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

General view of the flight deck of the Orbiter Discovery looking forward from behind the commander's seat looking towards the pilot's station. Note the numerous Velcro pads located throughout the crew compartment, used to secure frequently used items when in zero gravity. This image was taken at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
"Looking Back, Looking Forward, and Pulling It Together: A Celebration of Teaching Excellence in the Minnesota State Universities." Proceedings of the Bush Foundation Undergraduate Teaching Conference (Brooklyn Park, Minnesota, April 27-28, 1995).

ERIC Educational Resources Information Center

Bemidji State Univ., Minn.

This conference proceedings consists of three keynote addresses and four representative papers. Keynote addresses include: "Impediments to Critical Thinking: Cultural Forces and Our Own 'Stuckness'" by Chet Meyers (which identifies social and cultural elements which make educational change difficult but critically important);…
On JALT 95: Curriculum and Evaluation. Proceedings of the JALT International Conference on Language Teaching/Learning (22nd, Nagoya, Japan, November 1995). Section One: Looking Back, Looking Forward.

ERIC Educational Resources Information Center

Wright, Andrew; And Others

Three papers on the outlook for second language teaching and learning introduce the conference on second language curriculum and evaluation. "My Story of Language Teaching" (Andrew Wright) describes a variety of personal and professional experiences in the course of 50 years of language teaching, each highlighting emerging social values…
A multirotor platform for mapping and inspecting sub-vertical rock faces

NASA Astrophysics Data System (ADS)

Thoeni, Klaus; Renton, Christopher; Giacomini, Anna

2016-04-01

Only in recent years UAS technology has become accessible to everyone and, hence, it is rapidly becoming a valuable tool for researchers and scientists (Westoby et al., 2012; Nex and Remondino, 2014). Electric multicopters (i.e., multirotor helicopters) are one of the most exciting developments of the last couple of years. Only the development and implementation of advanced flight controllers made the use of multicopters possible. Generally being an aerodynamically unstable UAS they absolutely require a flight controller for stable flight. Several open-source and commercial flight controller are now available which makes it possible to build custom UAS. The current work presents a custom build hexacopter (i.e., a multicopter with six rotors) which was specifically developed for 3D mapping and inspection of sub-vertical rock faces. The main sensor installed on the platform is a Canon 100D DSLR camera. The camera is attached to a two axis gimbal. The roll angle is automatically controlled to keep the camera level during the flight whereas the user controls the tilt angle. The two forward facing arms of the hexacopter have been raised, i.e., they are located higher than the other four propellers (Mantis arms). This provides a clear field of view when looking forward and even makes it possible to look slightly upward without having the propellers in the field of view. A DJI A2 flight controller is installed on the platform and an additional FPV camera can be switched on if pictures are taken in manual mode. So far the flights are all performed in manual mode. The fact that the platform is generally flying very close to very irregular sub-vertical rock faces makes autonomous flights in GPS mode almost impossible. In addition, GPS reception is often very poor around sub-vertical rock faces. One main issue when flying in manual mode is to keep the hexacopter at a constant distance from the surface. As the rock surface gets higher and higher it becomes more and more difficult for the pilot to estimate this distance. Hence, some modifications are currently being implemented. A lightweight laser sensor will be installed to measure the distance between the drone and the sub-vertical rock surface in real time. The information will be transmitted to the pilot who can keep the hexacopter at the required distance. Some applications of the developed platform for the 3D mapping of highwalls in Australian coal mines are presented and the advantages over conventional methods (e.g., Thoeni et al., 2012) are discussed. References Nex, F., Remondino, F. (2014) UAV for 3D mapping applications: a review. Applied Geomatics 6(1), 1-15. Thoeni, K., Irschara, A., Giacomini, A. (2012) Efficient photogrammetric reconstruction of highwalls in open pit coal mines. 16th Australasian Remote Sensing and Photogrammetry Conference, 85-90. Westoby, M.J., Brasington, J., Glasser, N.F., Hambrey, M.J., Reynolds, J.M. (2012) 'Structure-from-Motion' photogrammetry: A low-cost, effective tool for geoscience applications. Geomorphology 179, 300-314.
A spaceborne optical interferometer: The JPL CSI mission focus

NASA Astrophysics Data System (ADS)

Laskin, R. A.

1989-08-01

The JPL Control Structure Interaction (CSI) program is part of the larger NASA-wide CSI program. Within this larger context, the JPL CSI program will emphasize technology for systems that demand micron or sub-micron level control, so-called Micro-Precision Controlled Structures (u-PCS). The development of such technology will make it practical to fly missions with large optical or large precision antenna systems. In keeping with the focused nature of the desired technology, the JPL approach is to identify a focus mission, develop the focus mission CSI system design to a preliminary level, and then use this design to drive out requirements for CSI technology development in the design and analysis, ground test bed, and flight experiment areas.
STS-29 Commander Coats in JSC fixed base (FB) shuttle mission simulator (SMS)

NASA Technical Reports Server (NTRS)

1986-01-01

STS-29 Discovery, Orbiter Vehicle (OV) 103, Commander Michael L. Coats sits at commanders station forward flight deck controls in JSC fixed base (FB) shuttle mission simulator (SMS). Coats, wearing communications kit assembly headset and flight coveralls, looks away from forward control panels to aft flight deck. Pilots station seat back appears in foreground. FB-SMS is located in JSC Mission Simulation and Training Facility Bldg 5.
STS-28 Columbia, OV-102, Pilot Richards at forward flight deck pilots station

NASA Technical Reports Server (NTRS)

1989-01-01

Pilot Richard N. Richards, sitting at forward flight deck pilots station controls, looks back to aft flight deck during STS-28, a Department of Defense (DOD) dedicated mission. Control panels F7 and F8 and portable laptop computer propped on panel F4 appear in front of Richards. Behind him are the pilots seat seat back and head rest. A stuffed toy animal is positioned on C1 panel.
Real-Time Integrity Monitoring of Stored Geo-Spatial Data Using Forward-Looking Remote Sensing Technology

NASA Technical Reports Server (NTRS)

Young, Steven D.; Harrah, Steven D.; deHaag, Maarten Uijt

2002-01-01

Terrain Awareness and Warning Systems (TAWS) and Synthetic Vision Systems (SVS) provide pilots with displays of stored geo-spatial data (e.g. terrain, obstacles, and/or features). As comprehensive validation is impractical, these databases typically have no quantifiable level of integrity. This lack of a quantifiable integrity level is one of the constraints that has limited certification and operational approval of TAWS/SVS to "advisory-only" systems for civil aviation. Previous work demonstrated the feasibility of using a real-time monitor to bound database integrity by using downward-looking remote sensing technology (i.e. radar altimeters). This paper describes an extension of the integrity monitor concept to include a forward-looking sensor to cover additional classes of terrain database faults and to reduce the exposure time associated with integrity threats. An operational concept is presented that combines established feature extraction techniques with a statistical assessment of similarity measures between the sensed and stored features using principles from classical detection theory. Finally, an implementation is presented that uses existing commercial-off-the-shelf weather radar sensor technology.
14 CFR 25.1321 - Arrangement and visibility.

Code of Federal Regulations, 2010 CFR

2010-01-01

... and line of vision when he is looking forward along the flight path. (b) The flight instruments... center position. (c) Required powerplant instruments must be closely grouped on the instrument panel. In...
14 CFR 25.1321 - Arrangement and visibility.

Code of Federal Regulations, 2011 CFR

2011-01-01

... and line of vision when he is looking forward along the flight path. (b) The flight instruments... center position. (c) Required powerplant instruments must be closely grouped on the instrument panel. In...
ALMA observations of protoplanetary disks

NASA Astrophysics Data System (ADS)

Hogerheijde, Michiel

2015-08-01

The Universe is filled with planetary systems, as recent detections of exo-planets have shown. Such systems grow out of disks of gas and dust that surround newly formed stars. The ground work for our understanding of the structure, composition, and evolution of such disks has been laid with infrared telescopes in the 1980's, 1990's, and 2000's, as well as with millimeter interferometers operating in the United States, France, and Japan. With the construction of the Atacama Large Millimeter / submillimeter Array, a new era of studying planet-forming disks has started. The unprecedented leap in sensitivity and angular resolution that ALMA offers, has truely revolutionized our understanding of disks. No longer featureless objects consisting of gas and smalll dust, they are now seen to harbor a rich structure and chemistry. The ongoing planet-formation process sculpts many disks into systems of rings and arcs; grains grown to millimeter-sizes collect in high-pressure areas where they could grow out to asteroids or comets or further generations of planets. This wealth of new information directly addresses bottlenecks in our theoretical understanding of planet formation, such as the question how grains can grow past the 'meter-sized' barrier or overcome the 'drift barrier', and how gas and ice evolve together and ultimately determine the elemental compositions of both giant and terrestrial planets. I will review the recent ALMA results on protoplanetary disks, presenting results on individual objects and from the first populations studies. I will conclude with a forward look, on what we might expect from ALMA in this area for the years and decades to come.
Axial Extension (Posture Exercise)

MedlinePlus

... changes our patterns of movement and our breathing efficiency. How to do it: Look straight forward. Tuck ... a Donation Make an Appointment Patient Portal Careers Locations Partnerships Newsroom Calendar Español Follow Us Sign up ...
You Know You Are Getting Better When...

MedlinePlus

... are made in ignorance. You look forward to holidays. Once dreaded occasions can now be anticipated with ... comfortable going once a month or only on holidays or other special occasions. You can find something ...
A 20fs synchronization system for lasers and cavities in accelerators and FELs

NASA Astrophysics Data System (ADS)

Wilcox, R. B.; Byrd, J. M.; Doolittle, L. R.; Huang, G.; Staples, J. W.

2010-02-01

A fiber-optic RF distribution system has been developed for synchronizing lasers and RF plants in short pulse FELs. Typical requirements are 50-100fs rms over time periods from 1ms to several hours. Our system amplitude modulates a CW laser signal, senses fiber length using an interferometer, and feed-forward corrects the RF phase digitally at the receiver. We demonstrate less than 15fs rms error over 12 hours, between two independent channels with a fiber path length difference of 200m and transmitting S-band RF. The system is constructed using standard telecommunications components, and uses regular telecom fiber.
Forward-looking farmers owning multiple potential wetland restoration sites: implications for efficient restoration

NASA Astrophysics Data System (ADS)

Schroder (Kushch), Svetlana; Lang, Zhengxin; Rabotyagov, Sergey

2018-04-01

Wetland restoration can increase the provision of multiple non-market ecosystem services. Environmental and socio-economic factors need to be accounted for when land is withdrawn from agriculture and wetlands are restored. We build multi-objective optimization models to provide decision support for wetland restoration in the Le Sueur river watershed in Southern Minnesota. We integrate environmental objectives of sediment reduction and habitat protection with socio-economic factors associated with the overlap of private land with potential wetland restoration sites in the watershed and the costs representing forward-looking farmers voluntarily taking land out of agricultural production in favor of wetland restoration. Our results demonstrate that the inclusion of these factors early on in the restoration planning process affects both the total costs of the restoration project and the spatial distribution of optimally selected wetland restoration sites.
Formation Flying and the Stellar Imager Mission Concept

NASA Technical Reports Server (NTRS)

Carpenter, Kenneth G.

2003-01-01

The Stellar Imager (SI) is envisioned as a space-based, W-optical interferometer composed of 10 or more one-meter class elements distributed with a maximum baseline of 0.5 km. image stars and binaries with sufficient resolution to enable long-term studies of stellar magnetic activity patterns, for comparison with those on the sun. It will also support asteroseismology (acoustic imaging) to probe stellar internal structure, differential rotation, and large-scale circulations. SI will enable us to understand the various effects of the magnetic fields of stars, the dynamos that generate these fields, and the internal structure and dynamics of the stars. The ultimate goal of the mission is to achieve the best-possible forecasting of solar activity as a driver of climate and space weather on time scales ranging from months up to decades, and an understanding of the impact of stellar magnetic activity on life in the Universe. In this paper we briefly describe the scientific goals of the mission, the performance requirements needed to address these goals, and the "enabling technology" development efforts required, with specific attention for this meeting to the formation-flying aspects. It is designed to
Evidence for symmetry in the elementary process of bidirectional torque generation by the bacterial flagellar motor

PubMed Central

Nakamura, Shuichi; Kami-ike, Nobunori; Yokota, Jun-ichi P.; Minamino, Tohru; Namba, Keiichi

2010-01-01

The bacterial flagellar motor can rotate in both counterclockwise (CCW) and clockwise (CW) directions. It has been shown that the sodium ion-driven chimeric flagellar motor rotates with 26 steps per revolution, which corresponds to the number of FliG subunits that form part of the rotor ring, but the size of the backward step is smaller than the forward one. Here we report that the proton-driven flagellar motor of Salmonella also rotates with 26 steps per revolution but symmetrical in both CCW and CW directions with occasional smaller backward steps in both directions. Occasional shift in the stepping positions is also observed, suggesting the frequent exchange of stators in one of the 11–12 possible anchoring positions around the rotor. These observations indicate that the elementary process of torque generation by the cyclic association/dissociation of the stator with every FliG subunit along the circumference of the rotor is symmetric in CCW and CW rotation even though the structure of FliG is highly asymmetric and suggests a 180° rotation of a FliG domain for the rotor-stator interaction to reverse the direction of rotation. PMID:20876126

A bee in the corridor: centering and wall-following

NASA Astrophysics Data System (ADS)

Serres, Julien R.; Masson, Guillaume P.; Ruffier, Franck; Franceschini, Nicolas

2008-12-01

In an attempt to better understand the mechanism underlying lateral collision avoidance in flying insects, we trained honeybees ( Apis mellifera) to fly through a large (95-cm wide) flight tunnel. We found that, depending on the entrance and feeder positions, honeybees would either center along the corridor midline or fly along one wall. Bees kept following one wall even when a major (150-cm long) part of the opposite wall was removed. These findings cannot be accounted for by the “optic flow balance” hypothesis that has been put forward to explain the typical bees’ “centering response” observed in narrower corridors. Both centering and wall-following behaviors are well accounted for, however, by a control scheme called the lateral optic flow regulator, i.e., a feedback system that strives to maintain the unilateral optic flow constant. The power of this control scheme is that it would allow the bee to guide itself visually in a corridor without having to measure its speed or distance from the walls.
Stable hovering of a jellyfish-like flying machine

PubMed Central

Ristroph, Leif; Childress, Stephen

2014-01-01

Ornithopters, or flapping-wing aircraft, offer an alternative to helicopters in achieving manoeuvrability at small scales, although stabilizing such aerial vehicles remains a key challenge. Here, we present a hovering machine that achieves self-righting flight using flapping wings alone, without relying on additional aerodynamic surfaces and without feedback control. We design, construct and test-fly a prototype that opens and closes four wings, resembling the motions of swimming jellyfish more so than any insect or bird. Measurements of lift show the benefits of wing flexing and the importance of selecting a wing size appropriate to the motor. Furthermore, we use high-speed video and motion tracking to show that the body orientation is stable during ascending, forward and hovering flight modes. Our experimental measurements are used to inform an aerodynamic model of stability that reveals the importance of centre-of-mass location and the coupling of body translation and rotation. These results show the promise of flapping-flight strategies beyond those that directly mimic the wing motions of flying animals. PMID:24430122
Flight-Effects on Predicted Fan Fly-By Noise

NASA Technical Reports Server (NTRS)

Heidmann, M. F.; Clark, B. J.

1977-01-01

The impact on PNLT (Perceived Noise Level, Tone corrected) and Fly-by EPNL (Effective Perceived Noise Level) when forward motion reduces the noise generated by the bypass fan of an aircraft engine was studied. Calculated noise spectra for a typical subsonic tip speed fan designed for blade passage frequency (BPF) tone cutoff were translated in frequency by systematically varying the BPF from 0.5 to 8 kHz. Two cases of predicted flight-effects on fan source noises were considered: reduced BPF tone level of 8 db and reduced broadband noise level of about 2 db in addition to reduced tone level. The maximum reduction in PNLT of the noise as emitted from the fan occurred when the BPF was at 4 kHz where the reductions were 7.4 and 10.0 db. The maximum reduction in EPNL of the noise as received during a 500-foot altitude fly-by occurred when the BPF was at 2.5 kHz where the reductions were 5.0 and 7.8 db.
Control of forward swept wing configurations dominated by flight-dynamic/aeroelastic interactions

NASA Technical Reports Server (NTRS)

Rimer, M.; Chipman, R.; Muniz, B.

1984-01-01

An active control system concept for an aeroelastic wind-tunnel model of a statically unstable FSW configuration with wing-mounted stores is developed to provide acceptable longitudinal flying qualities while maintaining adequate flutter speed margin. On FSW configurations, the inherent aeroelastic wing divergence tendency causes strong flight-dynamic/aeroelastic interactions that in certain cases can produce a dynamic instability known as body-freedom flutter (BFF). The carriage of wing-mounted stores is shown to severely aggravate this problem. The control system developed combines a canard-based SAS with an Active Divergence/Flutter Suppression (ADFS) system which relies on wing-mounted sensors and a trailing-edge device (flaperon). Synergism between these two systems is exploited to obtain the flying qualities and flutter speed objectives.
Atmospheric Emitted Radiance Interferometer (AERI) Handbook

DOE Data Explorer

Gero, Jonathan; Hackel, Denny; Garcia, Raymond

2005-01-01

The atmospheric emitted radiance interferometer (AERI) is a ground-based instrument that measures the downwelling infrared radiance from the Earth's atmosphere. The observations have broad spectral content and sufficient spectral resolution to discriminate among gaseous emitters (e.g., carbon dioxide and water vapor) and suspended matter (e.g., aerosols, water droplets, and ice crystals). These upward-looking surface observations can be used to obtain vertical profiles of tropospheric temperature and water vapor, as well as measurements of trace gases (e.g., ozone, carbon monoxide, and methane) and downwelling infrared spectral signatures of clouds and aerosols.The AERI is a passive remote sounding instrument, employing a Fourier transform spectrometer operating in the spectral range 3.3-19.2 μm (520-3020 cm-1) at an unapodized resolution of 0.5 cm-1 (max optical path difference of 1 cm). The extended-range AERI (ER-AERI) deployed in dry climates, like in Alaska, have a spectral range of 3.3-25.0 μm (400-3020 cm-1) that allow measurements in the far-infrared region. Typically, the AERI averages views of the sky over a 16-second interval and operates continuously.
Onboard Interferometric SAR Processor for the Ka-Band Radar Interferometer (KaRIn)

NASA Technical Reports Server (NTRS)

Esteban-Fernandez, Daniel; Rodriquez, Ernesto; Peral, Eva; Clark, Duane I.; Wu, Xiaoqing

2011-01-01

An interferometric synthetic aperture radar (SAR) onboard processor concept and algorithm has been developed for the Ka-band radar interferometer (KaRIn) instrument on the Surface and Ocean Topography (SWOT) mission. This is a mission- critical subsystem that will perform interferometric SAR processing and multi-look averaging over the oceans to decrease the data rate by three orders of magnitude, and therefore enable the downlink of the radar data to the ground. The onboard processor performs demodulation, range compression, coregistration, and re-sampling, and forms nine azimuth squinted beams. For each of them, an interferogram is generated, including common-band spectral filtering to improve correlation, followed by averaging to the final 1 1-km ground resolution pixel. The onboard processor has been prototyped on a custom FPGA-based cPCI board, which will be part of the radar s digital subsystem. The level of complexity of this technology, dictated by the implementation of interferometric SAR processing at high resolution, the extremely tight level of accuracy required, and its implementation on FPGAs are unprecedented at the time of this reporting for an onboard processor for flight applications.
Looking Back, Going Forward: The Carnegie Commission Tuition Policy. The New Millennium Project on Higher Education Costs, Pricing, and Productivity Working Paper.

ERIC Educational Resources Information Center

Wellman, Jane V.

In thinking about the design of public policy for higher education finance, it may be instructive to look back at the evolution of finance policy and how it has worked over the last three decades of U.S. higher education. The vehicle for this exploration is the tuition policy framework developed by the Carnegie Commission on Higher Education…
Spectral-domain optical coherence tomography for endoscopic imaging

NASA Astrophysics Data System (ADS)

Chen, Xiaodong; Li, Qiao; Li, Wanhui; Wang, Yi; Yu, Daoyin

2007-02-01

Optical coherence tomography (OCT) is an emerging cross-sectional imaging technology. It uses broadband light sources to achieve axial image resolutions on the few micron scale. OCT is widely applied to medical imaging, it can get cross-sectional image of bio-tissue (transparent and turbid) with non-invasion and non-touch. In this paper, the principle of OCT is presented and the crucial parameters of the system are discussed in theory. With analysis of different methods and medical endoscopic system's feature, a design which combines the spectral domain OCT (SDOCT) technique and endoscopy is put forward. SDOCT provides direct access to the spectrum of the optical signal. It is shown to provide higher imaging speed when compared to time domain OCT. At the meantime, a novel OCT probe which uses advanced micromotor to drive reflecting prism is designed according to alimentary tract endoscopic feature. A simple optical coherence tomography system has been developed based on a fiber-based Michelson interferometer and spectrometer. An experiment which uses motor to drive prism to realize rotating imaging is done. Images obtained with this spectral interferometer are presented. The results verify the feasibility of endoscopic optical coherence tomography system with rotating scan.
Research on effects of phase error in phase-shifting interferometer

NASA Astrophysics Data System (ADS)

Wang, Hongjun; Wang, Zhao; Zhao, Hong; Tian, Ailing; Liu, Bingcai

2007-12-01

Referring to phase-shifting interferometry technology, the phase shifting error from the phase shifter is the main factor that directly affects the measurement accuracy of the phase shifting interferometer. In this paper, the resources and sorts of phase shifting error were introduction, and some methods to eliminate errors were mentioned. Based on the theory of phase shifting interferometry, the effects of phase shifting error were analyzed in detail. The Liquid Crystal Display (LCD) as a new shifter has advantage as that the phase shifting can be controlled digitally without any mechanical moving and rotating element. By changing coded image displayed on LCD, the phase shifting in measuring system was induced. LCD's phase modulation characteristic was analyzed in theory and tested. Based on Fourier transform, the effect model of phase error coming from LCD was established in four-step phase shifting interferometry. And the error range was obtained. In order to reduce error, a new error compensation algorithm was put forward. With this method, the error can be obtained by process interferogram. The interferogram can be compensated, and the measurement results can be obtained by four-step phase shifting interferogram. Theoretical analysis and simulation results demonstrate the feasibility of this approach to improve measurement accuracy.
Static Aeroelasticity in Combat Aircraft.

DTIC Science & Technology

1986-01-01

stiffness scaled beam machined along a predicted elastic axis, and load iola- tion cuts forward and aft of the beam, has proved to be most successful...aircraft components. Many papers deal with the activities in the field of structural optimization.’ 4sing fiber composites , a new design technique...Supersonic Design Composite Structures Fly - by - Wire Thin Profiles Aeroelastic Tailoring Unstable Aircraft V Variable Camber Lght Weight Pilot Handling
Hang Gliders for Sport

NASA Technical Reports Server (NTRS)

1976-01-01

Hang gliding is growing rapidly. Free Flight produces 1,000 gliders a month and other companies are entering the field. Wing is simple to control, pulling back on control bar allows you to pick up speed and at the same time lowers your altitude. Pushing forward slows your speed and levels you off. Birdmen can choose from prone, upright or swing seat harnesses in either kits or ready-to-fly gliders.
Enhanced thrust and speed revealed in the forward flight of a butterfly with transient body translation.

PubMed

Fei, Yueh-Han John; Yang, Jing-Tang

2015-09-01

A butterfly with broad wings, flapping at a small frequency, flies an erratic trajectory at an inconstant speed. A large variation of speed within a cycle is observed in the forward flight of a butterfly. A self-propulsion model to simulate a butterfly is thus created to investigate the transient translation of the body; the results, which are in accordance with experimental data, show that the shape of the variation of the flight speed is similar to a sinusoidal wave with a maximum (J=0.89) at the beginning of the downstroke, and a decrease to a minimum (J=0.17) during a transition from downstroke to upstroke; the difference between the extrema of the flight speed is enormous in a flapping cycle. At a high speed, a clapping motion of the butterfly wings decreases the generation of drag. At a small speed, a butterfly is able to capture the induced wakes generated in a downstroke, and effectively generates a thrust at the beginning of an upstroke. The wing motion of a butterfly skillfully interacts with its speed so as to enable an increased speed with the same motion. Considering a butterfly to fly in a constant inflow leads to either an underestimate of its speed or an overestimate of its generated lift, which yields an inaccurate interpretation of the insect's flight. Our results reveal the effect of transient translation on a butterfly in forward flight, which is especially important for an insect with a small flapping frequency.
Enhanced thrust and speed revealed in the forward flight of a butterfly with transient body translation

NASA Astrophysics Data System (ADS)

Fei, Yueh-Han John; Yang, Jing-Tang

2015-09-01

A butterfly with broad wings, flapping at a small frequency, flies an erratic trajectory at an inconstant speed. A large variation of speed within a cycle is observed in the forward flight of a butterfly. A self-propulsion model to simulate a butterfly is thus created to investigate the transient translation of the body; the results, which are in accordance with experimental data, show that the shape of the variation of the flight speed is similar to a sinusoidal wave with a maximum (J =0.89 ) at the beginning of the downstroke, and a decrease to a minimum (J =0.17 ) during a transition from downstroke to upstroke; the difference between the extrema of the flight speed is enormous in a flapping cycle. At a high speed, a clapping motion of the butterfly wings decreases the generation of drag. At a small speed, a butterfly is able to capture the induced wakes generated in a downstroke, and effectively generates a thrust at the beginning of an upstroke. The wing motion of a butterfly skillfully interacts with its speed so as to enable an increased speed with the same motion. Considering a butterfly to fly in a constant inflow leads to either an underestimate of its speed or an overestimate of its generated lift, which yields an inaccurate interpretation of the insect's flight. Our results reveal the effect of transient translation on a butterfly in forward flight, which is especially important for an insect with a small flapping frequency.
Curricular Sense and Sanity

ERIC Educational Resources Information Center

Korfmacher, William Charles

1975-01-01

Discusses, from a college standpoint, the curriculum of a secondary school whose pupils are looking forward to college. Indicates that amid social change students will continue to need science and mathematics, history, fine arts, foreign languages, and English. (JT)
Sensing and Measurement Architecture for Grid Modernization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taft, Jeffrey D.; De Martini, Paul

2016-02-01

This paper addresses architecture for grid sensor networks, with primary emphasis on distribution grids. It describes a forward-looking view of sensor network architecture for advanced distribution grids, and discusses key regulatory, financial, and planning issues.
CGH Roundtable on HPV Screening

Cancer.gov

The NCI Center for Global Health extends its congratulations on Pink Ribbon Red Ribbon’s fifth anniversary and continues to build on its three-year partnership. We look forward to participating in PRRR fifth-anniversary-related activities.
Millimeter wave radar for automobile crash avoidance systems

NASA Astrophysics Data System (ADS)

Huguenin, G. Richard

1994-08-01

Low cost, millimeter wave, forward looking radar sensors for applications in Autonomous Collision Warning and Autonomous Intelligent Cruise Control systems will be described. These safety related systems promise the largest payoff in preventing highway crashes.
Valley Fill Design and Construction Alternatives to Improve Ecological Performance

EPA Pesticide Factsheets

This presentation discusses; current challenges, comprehensive approaches, BMPs, the Middlefork Development, the Guy Cove project, and a path forward when looking at construction alternatives to improve the ecological performance of valley fills.
Space-to-Ground: 2017: 12/22/2017

NASA Image and Video Library

2017-12-21

We look back at a record-breaking year, and forward to what should be a transformational year on station. NASA's Space to Ground is your weekly update on what's happening aboard the International Space Station.
Figuring Out Health News

MedlinePlus

... risk for a health condition. Those studies, called retrospective studies , can provide useful clues, but they're only as reliable as a person's memory or the accuracy of medical records. Prospective studies are usually better. They look forward, not ...

Problem-Solving Test: Targeted Gene Disruption

ERIC Educational Resources Information Center

Szeberenyi, Jozsef

2008-01-01

Mutational inactivation of a specific gene is the most powerful technique to analyze the biological function of the gene. This approach has been used for a long time in viruses, bacteria, yeast, and fruit fly, but looked quite hopeless in more complex organisms. Targeted inactivation of specific genes (also known as knock-out mutation) in mice is…
Earth Observation

NASA Image and Video Library

2014-08-03

ISS040-E-087412 (30 July 2014) --- An area of sun glint near the horizon caught the eye of one of the Expedition 40 crew members as the International Space Station was flying roughly 225 nautical miles above a point in the Pacific Ocean a few hundred miles southeast of the Philippines on July 30, 2014. The view is looking northwestward.
Walk, Fly, or Teleport to Learning: Virtual Worlds in the Classroom

ERIC Educational Resources Information Center

Yoder, Maureen Brown

2009-01-01

For educators looking for new ways to engage their students, multiuser virtual environments (MUVEs) offer a great opportunity for creative teaching and learning. MUVEs teach students social, technical, and practical life skills in a setting that is engaging and playful. One might be surprised how much these virtual environments teach students…
Flight control of fruit flies: dynamic response to optic flow and headwind.

PubMed

Lawson, Kiaran K K; Srinivasan, Mandyam V

2017-06-01

Insects are magnificent fliers that are capable of performing many complex tasks such as speed regulation, smooth landings and collision avoidance, even though their computational abilities are limited by their small brain. To investigate how flying insects respond to changes in wind speed and surrounding optic flow, the open-loop sensorimotor response of female Queensland fruit flies ( Bactrocera tryoni ) was examined. A total of 136 flies were exposed to stimuli comprising sinusoidally varying optic flow and air flow (simulating forward movement) under tethered conditions in a virtual reality arena. Two responses were measured: the thrust and the abdomen pitch. The dynamics of the responses to optic flow and air flow were measured at various frequencies, and modelled as a multicompartment linear system, which accurately captured the behavioural responses of the fruit flies. The results indicate that these two behavioural responses are concurrently sensitive to changes of optic flow as well as wind. The abdomen pitch showed a streamlining response, where the abdomen was raised higher as the magnitude of either stimulus was increased. The thrust, in contrast, exhibited a counter-phase response where maximum thrust occurred when the optic flow or wind flow was at a minimum, indicating that the flies were attempting to maintain an ideal flight speed. When the changes in the wind and optic flow were in phase (i.e. did not contradict each other), the net responses (thrust and abdomen pitch) were well approximated by an equally weighted sum of the responses to the individual stimuli. However, when the optic flow and wind stimuli were presented in counterphase, the flies seemed to respond to only one stimulus or the other, demonstrating a form of 'selective attention'. © 2017. Published by The Company of Biologists Ltd.
X-29 Research Pilot Rogers Smith

NASA Technical Reports Server (NTRS)

1988-01-01

Rogers Smith, a NASA research pilot, is seen here at the cockpit of the X-29 forward-swept-wing technology demonstrator at NASA's Ames-Dryden Flight Research Facility (later the Dryden Flight Research Center), Edwards, California, in 1988. The X-29 explored the use of advanced composites in aircraft construction; variable camber wing surfaces; the unique forward-swept-wing and its thin supercritical airfoil; strake flaps; and a computerized fly-by-wire flight control system that overcame the aircraft's instability. Grumman Aircraft Corporation built two X-29s. They were flight tested at Dryden from 1984 to 1992 in a joint NASA, DARPA (Defense Advanced Research Projects Agency) and U.S. Air Force program. Two X-29 aircraft, featuring one of the most unusual designs in aviation history, flew at the Ames-Dryden Flight Research Facility (now the Dryden Flight Research Center, Edwards, California) from 1984 to 1992. The fighter-sized X-29 technology demonstrators explored several concepts and technologies including: the use of advanced composites in aircraft construction; variable-camber wing surfaces; a unique forward- swept wing and its thin supercritical airfoil; strakes; close-coupled canards; and a computerized fly-by-wire flight control system used to maintain control of the otherwise unstable aircraft. Research results showed that the configuration of forward-swept wings, coupled with movable canards, gave pilots excellent control response at angles of attack of up to 45 degrees. During its flight history, the X-29 aircraft flew 422 research missions and a total of 436 missions. Sixty of the research flights were part of the X-29 follow-on 'vortex control' phase. The forward-swept wing of the X-29 resulted in reverse airflow, toward the fuselage rather than away from it, as occurs on the usual aft-swept wing. Consequently, on the forward-swept wing, the ailerons remained unstalled at high angles of attack. This provided better airflow over the ailerons and prevented stalling (loss of lift) at high angles of attack. Introduction of composite materials in the 1970s opened a new field of aircraft construction. It also made possible the construction of the X-29's thin supercritical wing. State-of-the-art composites allowed aeroelastic tailoring which, in turn, allowed the wing some bending but limited twisting and eliminated structural divergence within the flight envelope (i.e. deformation of the wing or the wing breaking off in flight). Additionally, composite materials allowed the wing to be sufficiently rigid for safe flight without adding an unacceptable weight penalty. The X-29 project consisted of two phases plus the follow-on vortex-control phase. Phase 1 demonstrated that the forward sweep of the X-29 wings kept the wing tips unstalled at the moderate angles of attack flown in that phase (a maximum of 21 degrees). Phase I also demonstrated that the aeroelastic tailored wing prevented structural divergence of the wing within the flight envelope, and that the control laws and control-surface effectiveness were adequate to provide artificial stability for an otherwise unstable aircraft. Phase 1 further demonstrated that the X-29 configuration could fly safely and reliably, even in tight turns. During Phase 2 of the project, the X-29, flying at an angle of attack of up to 67 degrees, demonstrated much better control and maneuvering qualities than computational methods and simulation models had predicted . During 120 research flights in this phase, NASA, Air Force, and Grumman project pilots reported the X-29 aircraft had excellent control response to an angle of attack of 45 degrees and still had limited controllability at a 67-degree angle of attack. This controllability at high angles of attack can be attributed to the aircraft's unique forward-swept wing- canard design. The NASA/Air Force-designed high-gain flight control laws also contributed to the good flying qualities. During the Air Force-initiated vortex-control phase, the X-29 successfully demonstrated vortex flow control (VFC). This VFC was more effective than expected in generating yaw forces, especially in high angles of attack where the rudder is less effective. VFC was less effective in providing control when sideslip (wind pushing on the side of the aircraft) was present, and it did little to decrease rocking oscillation of the aircraft. The X-29 vehicle was a single-engine aircraft, 48.1 feet long with a wing span of 27.2 feet. Each aircraft was powered by a General Electric F404-GE-400 engine producing 16,000 pounds of thrust. The program was a joint effort of the Department of Defense's Defense Advanced Research Projects Agency (DARPA), the U.S. Air Force, the Ames-Dryden Flight Research Facility, the Air Force Flight Test Center, and the Grumman Corporation. The program was managed by the Air Force's Wright Laboratory, Wright Patterson Air Force Base, Ohio.
ACHP | News | ACHP Issues Program Comments for DoD

Science.gov Websites

the Secretary of the Interior's Standards. The development of these initial five treatment measures is Artistic and Historic Works and ACHP staff. The ACHP looks forward to the development of further treatment
76 FR 53807 - Women's Equality Day, 2011

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-29

... dreams. We honor the heroes who have given of themselves to advance the causes of justice, opportunity... before, we renew our commitment to hold true to the dreams for which they fought, and we look forward to...
What Are Dentures?

MedlinePlus

... las dentaduras postizas? Wiggle, wiggle, and finally — it's free. Losing a tooth can be fun for a kid. You can put it under your pillow and look forward to finding some money there in the morning. And then you can ...
Asteroid Studies: A 35-Year Forecast

NASA Astrophysics Data System (ADS)

Rivkin, A. S.; Denevi, B. W.; Klima, R. L.; Ernst, C. M.; Chabot, N. L.; Barnouin, O. S.; Cohen, B. A.

2017-02-01

We are in an active time for asteroid studies, which fall at the intersection of science, planetary defense, human exploration, and in situ resource utilization. We look forward and extrapolate what the future may hold for asteroid science.
A candidate concept for display of forward-looking wind shear information

NASA Technical Reports Server (NTRS)

Hinton, David A.

1989-01-01

A concept is proposed which integrates forward-look wind shear information with airplane performance capabilities to predict future airplane energy state as a function of range. The information could be displayed to a crew either in terms of energy height or airspeed deviations. The anticipated benefits of the proposed display information concept are: (1) a wind shear hazard product that scales directly to the performance impact on the airplane and that has intuitive meaning to flight crews; (2) a reduction in flight crew workload by automatic processing of relevant hazard parameters; and (3) a continuous display of predicted airplane energy state if the approach is continued. Such a display may be used to improve pilot situational awareness or improve pilot confidence in wind shear alerts generated by other systems. The display is described and the algorithms necessary for implementation in a simulation system are provided.
Explosive hazard detection using MIMO forward-looking ground penetrating radar

NASA Astrophysics Data System (ADS)

Shaw, Darren; Ho, K. C.; Stone, Kevin; Keller, James M.; Popescu, Mihail; Anderson, Derek T.; Luke, Robert H.; Burns, Brian

2015-05-01

This paper proposes a machine learning algorithm for subsurface object detection on multiple-input-multiple-output (MIMO) forward-looking ground-penetrating radar (FLGPR). By detecting hazards using FLGPR, standoff distances of up to tens of meters can be acquired, but this is at the degradation of performance due to high false alarm rates. The proposed system utilizes an anomaly detection prescreener to identify potential object locations. Alarm locations have multiple one-dimensional (ML) spectral features, two-dimensional (2D) spectral features, and log-Gabor statistic features extracted. The ability of these features to reduce the number of false alarms and increase the probability of detection is evaluated for both co-polarizations present in the Akela MIMO array. Classification is performed by a Support Vector Machine (SVM) with lane-based cross-validation for training and testing. Class imbalance and optimized SVM kernel parameters are considered during classifier training.
Thirty years from now: future physics contributions in nuclear medicine.

PubMed

Bailey, Dale L

2014-12-01

This paper is the first in a series of invited perspectives by pioneers of nuclear medicine imaging and physics. A medical physicist and a nuclear medicine physician each take a backward and a forward look at the contributions of physics to nuclear medicine. Here, we provide a forward look from the medical physicist's perspective. The author examines a number of developments in nuclear medicine and discusses the ways in which physics has contributed to these. Future developments are postulated in the context of an increasingly personalised approach to medical diagnostics and therapies. A skill set for the next generation of medical physicists in nuclear medicine is proposed in the context of the increasing complexity of 'Molecular Imaging' in the next three decades. The author sees a shift away from 'traditional' roles in instrumentation QA to more innovative approaches in understanding radiobiology and human disease.
Checkpoint-based forward recovery using lookahead execution and rollback validation in parallel and distributed systems. Ph.D. Thesis, 1992

NASA Technical Reports Server (NTRS)

Long, Junsheng

1994-01-01

This thesis studies a forward recovery strategy using checkpointing and optimistic execution in parallel and distributed systems. The approach uses replicated tasks executing on different processors for forwared recovery and checkpoint comparison for error detection. To reduce overall redundancy, this approach employs a lower static redundancy in the common error-free situation to detect error than the standard N Module Redundancy scheme (NMR) does to mask off errors. For the rare occurrence of an error, this approach uses some extra redundancy for recovery. To reduce the run-time recovery overhead, look-ahead processes are used to advance computation speculatively and a rollback process is used to produce a diagnosis for correct look-ahead processes without rollback of the whole system. Both analytical and experimental evaluation have shown that this strategy can provide a nearly error-free execution time even under faults with a lower average redundancy than NMR.
STS-44 Atlantis, OV-104, crewmembers participate in JSC FB-SMS training

NASA Technical Reports Server (NTRS)

1991-01-01

STS-44 Atlantis, Orbiter Vehicle (OV) 104, Commander Frederick D. Gregory and Pilot Terence T. Henricks are stationed at their appointed positions on the forward flight deck of the Fixed Base (FB) Shuttle Mission Simulator (SMS) in JSC's Mission Simulation and Training Facility Bldg 5. Gregory (left) in the commanders seat and Henricks (right) in the pilots seat look back toward aft flight deck and the photographer. Seat backs appear in the foreground and forward flight deck control panels in the background.
Pilot Overmyer looks over food selections and experiments with beverage

NASA Technical Reports Server (NTRS)

1982-01-01

Pilot Overmyer, using beverage container and drinking straw secured in meal tray assembly (ASSY), experiments with microgravity chararcteristics of liquid on middeck in front of forward lockers. Overmyer also looks over packages of food attached to middeck lockers in meal tray assemblies. Carry-on food warmer appears overhead and other meal tray assemblies, personal hygiene mirror assy, personal hygiene kit, and portrait of G.W.S. Abbey, JSC's Director of Flight Operations, appear on lockers.
Multifunctional Catheters Combining Intracardiac Ultrasound Imaging and Electrophysiology Sensing

PubMed Central

Stephens, Douglas N.; Cannata, Jonathan; Liu, Ruibin; Zhao, Jian Zhong; Shung, K. Kirk; Nguyen, Hien; Chia, Raymond; Dentinger, Aaron; Wildes, Douglas; Thomenius, Kai E.; Mahajan, Aman; Shivkumar, Kalyanam; Kim, Kang; O’Donnell, Matthew; Nikoozadeh, Amin; Oralkan, Omer; Khuri-Yakub, Pierre T.; Sahn, David J.

2015-01-01

A family of 3 multifunctional intracardiac imaging and electrophysiology (EP) mapping catheters has been in development to help guide diagnostic and therapeutic intracardiac EP procedures. The catheter tip on the first device includes a 7.5 MHz, 64-element, side-looking phased array for high resolution sector scanning. The second device is a forward-looking catheter with a 24-element 14 MHz phased array. Both of these catheters operate on a commercial imaging system with standard software. Multiple EP mapping sensors were mounted as ring electrodes near the arrays for electrocardiographic synchronization of ultrasound images and used for unique integration with EP mapping technologies. To help establish the catheters’ ability for integration with EP interventional procedures, tests were performed in vivo in a porcine animal model to demonstrate both useful intracardiac echocardiographic (ICE) visualization and simultaneous 3-D positional information using integrated electroanatomical mapping techniques. The catheters also performed well in high frame rate imaging, color flow imaging, and strain rate imaging of atrial and ventricular structures. The companion paper of this work discusses the catheter design of the side-looking catheter with special attention to acoustic lens design. The third device in development is a 10 MHz forward-looking ring array that is to be mounted at the distal tip of a 9F catheter to permit use of the available catheter lumen for adjunctive therapy tools. PMID:18986948
Multifunctional catheters combining intracardiac ultrasound imaging and electrophysiology sensing.

PubMed

Stephens, D N; Cannata, J; Liu, Ruibin; Zhao, Jian Zhong; Shung, K K; Nguyen, Hien; Chia, R; Dentinger, A; Wildes, D; Thomenius, K E; Mahajan, A; Shivkumar, K; Kim, Kang; O'Donnell, M; Nikoozadeh, A; Oralkan, O; Khuri-Yakub, P T; Sahn, D J

2008-07-01

A family of 3 multifunctional intracardiac imaging and electrophysiology (EP) mapping catheters has been in development to help guide diagnostic and therapeutic intracardiac EP procedures. The catheter tip on the first device includes a 7.5 MHz, 64-element, side-looking phased array for high resolution sector scanning. The second device is a forward-looking catheter with a 24-element 14 MHz phased array. Both of these catheters operate on a commercial imaging system with standard software. Multiple EP mapping sensors were mounted as ring electrodes near the arrays for electrocardiographic synchronization of ultrasound images and used for unique integration with EP mapping technologies. To help establish the catheters' ability for integration with EP interventional procedures, tests were performed in vivo in a porcine animal model to demonstrate both useful intracardiac echocardiographic (ICE) visualization and simultaneous 3-D positional information using integrated electroanatomical mapping techniques. The catheters also performed well in high frame rate imaging, color flow imaging, and strain rate imaging of atrial and ventricular structures. The companion paper of this work discusses the catheter design of the side-looking catheter with special attention to acoustic lens design. The third device in development is a 10 MHz forward-looking ring array that is to be mounted at the distal tip of a 9F catheter to permit use of the available catheter lumen for adjunctive therapy tools.
Clutter and target discrimination in forward-looking ground penetrating radar using sparse structured basis pursuits

NASA Astrophysics Data System (ADS)

Camilo, Joseph A.; Malof, Jordan M.; Torrione, Peter A.; Collins, Leslie M.; Morton, Kenneth D.

2015-05-01

Forward-looking ground penetrating radar (FLGPR) is a remote sensing modality that has recently been investigated for buried threat detection. FLGPR offers greater standoff than other downward-looking modalities such as electromagnetic induction and downward-looking GPR, but it suffers from high false alarm rates due to surface and ground clutter. A stepped frequency FLGPR system consists of multiple radars with varying polarizations and bands, each of which interacts differently with subsurface materials and therefore might potentially be able to discriminate clutter from true buried targets. However, it is unclear which combinations of bands and polarizations would be most useful for discrimination or how to fuse them. This work applies sparse structured basis pursuit, a supervised statistical model which searches for sets of bands that are collectively effective for discriminating clutter from targets. The algorithm works by trying to minimize the number of selected items in a dictionary of signals; in this case the separate bands and polarizations make up the dictionary elements. A structured basis pursuit algorithm is employed to gather groups of modes together in collections to eliminate whole polarizations or sensors. The approach is applied to a large collection of FLGPR data for data around emplaced target and non-target clutter. The results show that a sparse structure basis pursuits outperforms a conventional CFAR anomaly detector while also pruning out unnecessary bands of the FLGPR sensor.
A precedence effect resolves phantom sound source illusions in the parasitoid fly Ormia ochracea

PubMed Central

Lee, Norman; Elias, Damian O.; Mason, Andrew C.

2009-01-01

Localizing individual sound sources under reverberant environmental conditions can be a challenge when the original source and its acoustic reflections arrive at the ears simultaneously from different paths that convey ambiguous directional information. The acoustic parasitoid fly Ormia ochracea (Diptera: Tachinidae) relies on a pair of ears exquisitely sensitive to sound direction to localize the 5-kHz tone pulsatile calling song of their host crickets. In nature, flies are expected to encounter a complex sound field with multiple sources and their reflections from acoustic clutter potentially masking temporal information relevant to source recognition and localization. In field experiments, O. ochracea were lured onto a test arena and subjected to small random acoustic asymmetries between 2 simultaneous sources. Most flies successfully localize a single source but some localize a ‘phantom’ source that is a summed effect of both source locations. Such misdirected phonotaxis can be elicited reliably in laboratory experiments that present symmetric acoustic stimulation. By varying onset delay between 2 sources, we test whether hyperacute directional hearing in O. ochracea can function to exploit small time differences to determine source location. Selective localization depends on both the relative timing and location of competing sources. Flies preferred phonotaxis to a forward source. With small onset disparities within a 10-ms temporal window of attention, flies selectively localize the leading source while the lagging source has minimal influence on orientation. These results demonstrate the precedence effect as a mechanism to overcome phantom source illusions that arise from acoustic reflections or competing sources. PMID:19332794
Forward-Looking Intracardiac Ultrasound Imaging Using a 1-D CMUT Array Integrated With Custom Front-End Electronics

PubMed Central

Nikoozadeh, Amin; Wygant, Ira O.; Lin, Der-Song; Oralkan, Ömer; Ergun, A. Sanlı; Stephens, Douglas N.; Thomenius, Kai E.; Dentinger, Aaron M.; Wildes, Douglas; Akopyan, Gina; Shivkumar, Kalyanam; Mahajan, Aman; Sahn, David J.; Khuri-Yakub, Butrus T.

2009-01-01

Minimally invasive catheter-based electrophysiological (EP) interventions are becoming a standard procedure in diagnosis and treatment of cardiac arrhythmias. As a result of technological advances that enable small feature sizes and a high level of integration, nonfluoroscopic intracardiac echocardiography (ICE) imaging catheters are attracting increasing attention. ICE catheters improve EP procedural guidance while reducing the undesirable use of fluoroscopy, which is currently the common catheter guidance method. Phased-array ICE catheters have been in use for several years now, although only for side-looking imaging. We are developing a forward-looking ICE catheter for improved visualization. In this effort, we fabricate a 24-element, fine-pitch 1-D array of capacitive micromachined ultrasonic transducers (CMUT), with a total footprint of 1.73 mm × 1.27 mm. We also design a custom integrated circuit (IC) composed of 24 identical blocks of transmit/receive circuitry, measuring 2.1 mm × 2.1 mm. The transmit circuitry is capable of delivering 25-V unipolar pulses, and the receive circuitry includes a transimpedance preamplifier followed by an output buffer. The CMUT array and the custom IC are designed to be mounted at the tip of a 10-Fr catheter for high-frame-rate forward-looking intracardiac imaging. Through-wafer vias incorporated in the CMUT array provide access to individual array elements from the back side of the array. We successfully flip-chip bond a CMUT array to the custom IC with 100% yield. We coat the device with a layer of polydimethylsiloxane (PDMS) to electrically isolate the device for imaging in water and tissue. The pulse-echo in water from a total plane reflector has a center frequency of 9.2 MHz with a 96% fractional bandwidth. Finally, we demonstrate the imaging capability of the integrated device on commercial phantoms and on a beating ex vivo rabbit heart (Langendorff model) using a commercial ultrasound imaging system. PMID:19126489

pre COBE history

Science.gov Websites

that insted of a balloon, we could try to fly from an airplane instead -- the C-141 run by NASA for infrared measurements. George went to NASA Ames to investigate. It looked difficult, since the hatch in the a memo format that might appeal to NASA. For the first time, Terry and George were added as co
WILLIAM GOLDING'S NOVEL--THE BACKWARD LOOK.

ERIC Educational Resources Information Center

PECK, CAROL FAULKNER

THE "SURPRISE ENDINGS" IN EACH OF WILLIAM GOLDING'S FIRST FOUR NOVELS OCCUR WHEN THE POINT OF VIEW SHIFTS FROM THE LIMITED WORLD OF THE NOVEL TO THE UNLIMITED WORLD OF REALITY. THE BOYS' RESCUE BY THE UNCOMPREHENDING OFFICER IN "LORD OF THE FLIES," REFOCUSES AND REINFORCES ALL THAT PRECEDES IT, AND THE FABLE, SUPERIMPOSED UPON REAL LIFE, BECOMES…
John Young-NASA’s Longest Serving Astronaut

NASA Image and Video Library

2018-01-06

This music video takes a look back at the NASA career of astronaut John Young, who died Friday night following complications from pneumonia at the age of 87. Young is the only agency astronaut to go into space as part of the Gemini, Apollo and space shuttle programs, and the first to fly into space six times.
Travaux Neuchatelois de linguistique (Neuchatel Working Papers in Linguistics).

ERIC Educational Resources Information Center

Neuchatel Univ. (Switzerland). Inst. de Linguistique.

This collection of working papers in linguistics includes four works. "Autour de la racine indo-europeenne 'pet-' ('voler') (pour servir a l'histoire des faits latins)" ("Concerning the Indo-European Root 'Pet-' ('To Fly') (To Serve as an Example of Latin Facts)" by Claude Sandoz looks at the Latin manifestations of the root and illustrates the…
Air force Thunderbirds flying above the Kennedy Space Center

NASA Image and Video Library

2007-02-01

Look -- It's a bird and a plane! A U.S. Air Force Thunderbird F-16D aircraft streaks through the sky past a slower-flying stork over the NASA News Center. The pilot is Maj. Tad Clark, who, after landing at the Shuttle Landing Facility, announced that Kennedy Space Center Visitor Complex will host the inaugural World Space Expo from Nov. 3 to 11, featuring an aerial salute by the Thunderbirds on its opening weekend. The Expo will create one of the largest displays of space artifacts, hardware and personalities ever assembled in one location with the objective to inspire, educate and engage the public by highlighting the achievements and benefits of space exploration.
How implicitly activated and explicitly acquired knowledge contribute to the effectiveness of retrieval cues.

PubMed

Nelson, Douglas L; Fisher, Serena L; Akirmak, Umit

2007-12-01

The extralist cued recall task simulates everyday reminding because a memory is encoded on the fly and retrieved later by an unexpected cue. Target words are studied individually, and recall is cued by associatively related words having preexisting forward links to them. In Experiments 1 and 2, forward cue-to-target and backward target-to-cue strengths were varied over an extended range in order to determine how these two sources of strength are related and which source has a greater effect. Forward and backward strengths had additive effects on recall, with forward strength having a consistently larger effect. The PIER2 model accurately predicted these findings, but a plausible generation-recognition version of the model, called PIER.GR, could not. In Experiment 3, forward and backward strengths, level of processing, and study time were varied in order to determine how preexisting lexical knowledge is related to knowledge acquired during the study episode. The main finding indicates that preexisting knowledge and episodic knowledge have additive effects on extralist cued recall. PIER2 can explain these findings because it assumes that these sources of strength contribute independently to recall, whereas the eSAM model cannot explain the findings because it assumes that the sources of strength are multiplicatively related.
3 CFR 8677 - Proclamation 8677 of May 13, 2011. World Trade Week, 2011

Code of Federal Regulations, 2012 CFR

2012-01-01

..., we must advance a robust, forward-looking trade agenda that emphasizes exports and domestic job... May 15 through May 21, 2011, as World Trade Week. I encourage all Americans to observe this week with...
Where to from here?

USDA-ARS?s Scientific Manuscript database

The Sustainable Feedstocks for Advanced Biofuels Workshop was developed to provide a science-based background and forward-looking strategies that would enable agriculture to help solve our nation’s bioenergy challenges. This summary chapter confirms that agricultural and forest resources have tremen...
AsMA journal covers, a history.

PubMed

Day, Pamela C

2014-01-01

The cover of our journal has changed quite often over the years. As we look forward to changing the name and design of the journal, it seems appropriate to reflect on the previous journal titles and covers. A brief history follows.
CGH Future Directions

Cancer.gov

Looking ahead, we have three major future directions that we believe will help us push forward in achieving NCI’s goal of advancing global cancer research, building expertise, and leveraging resources across nations to address the challenges of cancer and reduce cancer deaths worldwide.
Two-and three-dimensional unsteady lift problems in high-speed flight

NASA Technical Reports Server (NTRS)

Lomax, Harvard; Heaslet, Max A; Fuller, Franklyn B; Sluder, Loma

1952-01-01

The problem of transient lift on two- and three-dimensional wings flying at high speeds is discussed as a boundary-value problem for the classical wave equation. Kirchoff's formula is applied so that the analysis is reduced, just as in the steady state, to an investigation of sources and doublets. The applications include the evaluation of indicial lift and pitching-moment curves for two-dimensional sinking and pitching wings flying at Mach numbers equal to 0, 0.8, 1.0, 1.2 and 2.0. Results for the sinking case are also given for a Mach number of 0.5. In addition, the indicial functions for supersonic-edged triangular wings in both forward and reverse flow are presented and compared with the two-dimensional values.
Real-time Enhancement, Registration, and Fusion for a Multi-Sensor Enhanced Vision System

NASA Technical Reports Server (NTRS)

Hines, Glenn D.; Rahman, Zia-ur; Jobson, Daniel J.; Woodell, Glenn A.

2006-01-01

Over the last few years NASA Langley Research Center (LaRC) has been developing an Enhanced Vision System (EVS) to aid pilots while flying in poor visibility conditions. The EVS captures imagery using two infrared video cameras. The cameras are placed in an enclosure that is mounted and flown forward-looking underneath the NASA LaRC ARIES 757 aircraft. The data streams from the cameras are processed in real-time and displayed on monitors on-board the aircraft. With proper processing the camera system can provide better-than- human-observed imagery particularly during poor visibility conditions. However, to obtain this goal requires several different stages of processing including enhancement, registration, and fusion, and specialized processing hardware for real-time performance. We are using a real-time implementation of the Retinex algorithm for image enhancement, affine transformations for registration, and weighted sums to perform fusion. All of the algorithms are executed on a single TI DM642 digital signal processor (DSP) clocked at 720 MHz. The image processing components were added to the EVS system, tested, and demonstrated during flight tests in August and September of 2005. In this paper we briefly discuss the EVS image processing hardware and algorithms. We then discuss implementation issues and show examples of the results obtained during flight tests. Keywords: enhanced vision system, image enhancement, retinex, digital signal processing, sensor fusion
Search for extraterrestrial planets: the DARWIN mission

NASA Astrophysics Data System (ADS)

d'Arcio, Luigi; Karlsson, Anders; Bavdaz, Marcos; Jagemann, Thomas

2017-11-01

The ESA Darwin mission is primarily devoted to the detection of earth-like exoplanets and the spectroscopic characterization of their atmospheres for key tracers of life. Darwin is implemented as a free-flying stellar interferometer operating in the 6.5-20 micron wavelength range, and passively cooled to 40 K. The stellar flux is suppressed by destructive interference (nulling) over the full optical bandwidth. The planetary signal is extracted from the zodiacal background signature by modulating the optical response of the interferometer. The Darwin mission concept has evolved considerably in the past years. The original concept, based on six 1.5 m telescopes, has been replaced by more efficient designs using three to four three-meter class apertures. A novel 3D architecture is being evaluated, together with the conventional planar one, bearing the potential for significant volume and mass savings and enhanced straylight rejection. A number of technology development activities have been successfully completed, including optical metrology, optical delay lines, and single-mode infrared optical fibers. A second iteration of the Darwin System Assessment Study has been kicked off end 2005, aiming to consolidate the overall mission architecture and the preliminary design of the Darwin mission concept. This paper illustrates the current status of the Darwin mission, with special emphasis on the optical configuration and the technology development programme in the area of optics.
A UV LED-based Charge Management System for LISA

NASA Astrophysics Data System (ADS)

Conklin, John W.; Chilton, Andrew; Olatunde, Taiwo Janet; Apple, Stephen; Parry, Samantha; Ciani, Giacomo; Wass, Peter; Mueller, Guido

2018-01-01

The Laser Interferometer Space Antenna (LISA) will be the first space instrument to observe gravitational waves in the millihertz frequency band. LISA consists of three Sun-orbiting spacecraft that form an equilateral triangle, with each side measuring 2.5 million kilometers in length. Each spacecraft houses two free-floating test masses, which are protected from all disturbing forces so that they follow pure geodesics in spacetime. A drag-free control system commands micronewton thrusters to force the spacecraft to fly in formation with the test masses and laser interferometers measure the minute variations in the distance, or light travel time, between these free-falling test masses caused by gravitational waves. The LISA observatory, with a planned launch in the early 2030s, is led by the European Space Agency with significant contributions from NASA. Recently, NASA has initiated strategic investments in key LISA technologies that will likely become U.S. flight hardware contributions to this ground-breaking mission. One of these payload elements is the Charge Management System (CMS), which controls the electric potential of the test masses relative to their housings to reduce spurious force noise acting on the test masses to below the required level. This talk, presented by University of Florida team that leads the CMS development, will describe this vital U.S. contribution to the LISA mission in the context of the envisioned LISA payload architecture and its in-flight sensitivity to gravitational waves.
Group refractive index reconstruction with broadband interferometric confocal microscopy

PubMed Central

Marks, Daniel L.; Schlachter, Simon C.; Zysk, Adam M.; Boppart, Stephen A.

2010-01-01

We propose a novel method of measuring the group refractive index of biological tissues at the micrometer scale. The technique utilizes a broadband confocal microscope embedded into a Mach–Zehnder interferometer, with which spectral interferograms are measured as the sample is translated through the focus of the beam. The method does not require phase unwrapping and is insensitive to vibrations in the sample and reference arms. High measurement stability is achieved because a single spectral interferogram contains all the information necessary to compute the optical path delay of the beam transmitted through the sample. Included are a physical framework defining the forward problem, linear solutions to the inverse problem, and simulated images of biologically relevant phantoms. PMID:18451922
High-Frequency Gravitational Wave research and application to exoplanet studies

NASA Astrophysics Data System (ADS)

Baker, R. M. L., Jr.

2017-10-01

A discussion of the history of High-Frequency Gravitational Wave (HFGW) research is first presented. Over the years until modern times, starting with the first mention of Gravitational Waves by Poincaré in 1905 and the definition of HFGWs in 1961 by Robert L. Forward, the discussion continues concerning the international research efforts to detect HFGWs. The article highlights the accomplishments of HFGW researchers in China, Russia, Ukraine, England, Australia, Japan, Germany, Spain, Italy, and the United States. Comparisons are made with Low-Frequency Gravitational Wave (LFGW) research, especially concerning the Laser Interferometer Gravitational Observatory or LIGO. In fine, there are presented several interesting perspectives concerning cosmology, the speed of time and, especially, exoplanet applications of HFGWs.
The relationship of forward head posture and rounded shoulders with neck pain in Iranian office workers.

PubMed

Nejati, Parisa; Lotfian, Sara; Moezy, Azar; Moezy, Azar; Nejati, Mina

2014-01-01

Background Office workers spend a long period of time behind a computer during working hours. The relation between the posture of sitting during work with computer and neck pain is still debatable. Even though some researchers claim a significant difference in head posture between patients with neck pain and pain-free participants, the FHP (forward head posture) has not always been associated with neck pain in literature. So, the purpose of this study was to discover the relationship between neck pain and improper posture in the head, cervicothoracic spine and shoulders. This was a cross-sectional study to explore the relationships between neck pains, sagittal postures of cervical and thoracic spine and shoulders among office workers in two positions, straight looking forward and working position. 46 subjects without neck pain and 55 subjects with neck pain were evaluated using a photographic method. Thoracic and cervical postures were measured by the HT (High Thoracic), CV (Craniovertebral) angles respectively. Shoulder's posture was evaluated in the sagittal plane by the acromion protrusion. HT and CV angles were positively correlated with the presence of neck pain only in working position (p< 0.05). In straight looking forward position there was no significant difference between the two groups statistically (p>0.05). The difference of shoulder protrusion between symptomatic and asymptomatic groups was not significant. FHP and thoracic kyphosis were accompanied with neck pain. But shoulder posture was not correlated with neck pain.
A bio-inspired flying robot sheds light on insect piloting abilities.

PubMed

Franceschini, Nicolas; Ruffier, Franck; Serres, Julien

2007-02-20

When insects are flying forward, the image of the ground sweeps backward across their ventral viewfield and forms an "optic flow," which depends on both the groundspeed and the groundheight. To explain how these animals manage to avoid the ground by using this visual motion cue, we suggest that insect navigation hinges on a visual-feedback loop we have called the optic-flow regulator, which controls the vertical lift. To test this idea, we built a micro-helicopter equipped with an optic-flow regulator and a bio-inspired optic-flow sensor. This fly-by-sight micro-robot can perform exacting tasks such as take-off, level flight, and landing. Our control scheme accounts for many hitherto unexplained findings published during the last 70 years on insects' visually guided performances; for example, it accounts for the fact that honeybees descend in a headwind, land with a constant slope, and drown when travelling over mirror-smooth water. Our control scheme explains how insects manage to fly safely without any of the instruments used onboard aircraft to measure the groundheight, groundspeed, and descent speed. An optic-flow regulator is quite simple in terms of its neural implementation and just as appropriate for insects as it would be for aircraft.
Effect of time delay on flying qualities: An update

NASA Technical Reports Server (NTRS)

Smith, R. E.; Sarrafian, S. K.

1986-01-01

Flying qualities problems of modern, full-authority electronic flight control systems are most often related to the introduction of additional time delay in aircraft response to a pilot input. These delays can have a significant effect on the flying qualities of the aircraft. Time delay effects are reexamined in light of recent flight test experience with aircraft incorporating new technology. Data from the X-29A forward-swept-wing demonstrator, a related preliminary in-flight experiment, and other flight observations are presented. These data suggest that the present MIL-F-8785C allowable-control system time delay specifications are inadequate or, at least, incomplete. Allowable time delay appears to be a function of the shape of the aircraft response following the initial delay. The cockpit feel system is discussed as a dynamic element in the flight control system. Data presented indicate that the time delay associated with a significant low-frequency feel system does not result in the predicted degradation in aircraft flying qualities. The impact of the feel system is discussed from two viewpoints: as a filter in the control system which can alter the initial response shape and, therefore, the allowable time delay, and as a unique dynamic element whose delay contribution can potentially be discounted by special pilot loop closures.
Fort Riley Military Family Survey: Family Decisions to Accompany Soldiers Study

DTIC Science & Technology

2008-06-30

that I would be in, and not be coddled by my family at home. (Survey Participant) My husband loved the unit. They were cohesive and looked out for...was to finish my schooling. We just love this area! Friendly Community and they used to be very military friendly. But / guess with the shape our...conveniences in with a small town feel, and loved our former church and neighbors, and were looking forward to reconnecting with our fiends here. The position

The Post-Deployment Reintegration Scale: Associations with Organizational Commitment, Job-Related Affect, and Career Intentions

DTIC Science & Technology

2006-11-01

symptômes. Les auteurs ont découvert, par exemple, un lien entre des niveaux plus élevés d’attitudes négatives face à la réintégration personnelle...reintegration attitudes were not. This finding reinforces past theory and research showing that continuance commitment does not typically have a strong...Commitment in the workplace: Theory , research, and application. Thousand Oaks, CA: Sage. [19] Moon, H. (2001). Looking forward and looking back
A Look Back to Look Forward: Insights from 1919-1933 Applied to America’s 2011 Shift to the Pacific

DTIC Science & Technology

2013-03-01

22202-4302. Respondents should be aware that notwithstanding any other provision of law , no person shall be subject to any penalty for failing to comply...interests. 2 According to National Security Advisor Tom Donilon, the goal of the United States in the region was to ensure international law and...interests. Vital influences in the region include but are not limited to, the United States not ratifying the United Nations Convention on the Law
Looking Backward, Looking Forward: The Long, Torturous Struggle with Mosquitoes.

PubMed

Patterson, Gordon M

2016-10-19

The American anti-mosquito movement grew out of the discovery of the role of mosquitoes in transferring pathogens and public concern about pest and nuisance mosquitoes in the late 1800s. In the 20th century, organized mosquito control in the United States passed through three eras: mechanical, chemical, and integrated mosquito control. Mosquito control in the 21st century faces the challenge of emerging pathogens, invasive mosquito species, and balancing concerns about the environment with effective control strategies.
Boston Harbor National Park Service sites : alternative transportation systems evaluation report

DOT National Transportation Integrated Search

2001-06-01

This project puts forth a forward looking water-based transportation plan which would serve four NPS units in and around Boston Harbor: Boston Harbor Islands National Recreation Area, Boston National Historical Park, Salem Maritime Historic Site, and...
Semiannual Report: Apr 1, 2011 - Sept 30, 2011

EPA Pesticide Factsheets

Semiannual Report #EPA-350-R-11-036, Nov, 2011. We have made great progress and I look forward to fulfilling the new Office of Inspector General vision of being the best in public service and oversight for a better environment tomorrow.
Commander Rominger at the commander's workstation in Endeavour during STS-100

NASA Image and Video Library

2001-04-21

STS100-303-004 (19 April-1 May 2001) --- Astronaut Kent V. Rominger, STS-100 commander, looks over a procedures checklist at the commander's station on the forward flight deck of the Earth-orbiting Space Shuttle Endeavour.
Semiannual Report: Apr 1, 1998 - Sept 30, 1998

EPA Pesticide Factsheets

Semiannual Report #EPA-350-R-98-004, Nov, 1998. We look forward to working with the Administrator, Agency managers, Congress, and EPA's various stakeholders to help ensure that EPA delivers the maximum in environmental and health benefits to the public.
78 FR 19063 - Airworthiness Approval for Aircraft Forward-Looking Windshear and Turbulence Radar Systems

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-28

... Technical Standard Order (TSO)-C63d, Airborne Weather Radar Equipment. The objective is to leverage the..., Airborne Weather and Ground Mapping Pulsed Radars. The FAA and industry collaborated on the end-to-end...
4. Credit BG. View looking northeast at west facade of ...

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

4. Credit BG. View looking northeast at west facade of Test Stand 'E' 4259/E-60, solid rocket motor test facility. Wooden barricades to north and south of 4259/E-60 protect personnel and other facilities from flying debris in case of inadvertent explosions. Test Stand 'E' is accessed from the tunnel system by the inclined tube shown at the center of the image adjacent to a ladder. Racks running to the north (having the appearance of a low fence) carry electrical cables to Test Stand 'G' (Building 4271/E-72). - Jet Propulsion Laboratory Edwards Facility, Test Stand E, Edwards Air Force Base, Boron, Kern County, CA
51. (Credit JTL) Interior view (looking NW) of new pumping ...

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

51. (Credit JTL) Interior view (looking NW) of new pumping room built in 1921. In the right foreground is #1 low service pump built in 1897. Installed at McNeil in 1898, it was not moved during the building of this room in 1921. Beyond is a 5 mgd capacity Worthington-Snow cross-compound, duplex crank-and-fly-wheel engine built in 1920. Behind the worthington is an 8 mgd Allis-Chalmers engine of the same configuration. it was built in 1911, but not installed at McNeil until 1927. Both engines have condensers. - McNeil Street Pumping Station, McNeil Street & Cross Bayou, Shreveport, Caddo Parish, LA
Visual regulation of ground speed and headwind compensation in freely flying honey bees (Apis mellifera L.).

PubMed

Barron, Andrew; Srinivasan, Mandyam V

2006-03-01

There is now increasing evidence that honey bees regulate their ground speed in flight by holding constant the speed at which the image of the environment moves across the eye (optic flow). We have investigated the extent to which ground speed is affected by headwinds. Honey bees were trained to enter a tunnel to forage at a sucrose feeder placed at its far end. Ground speeds in the tunnel were recorded while systematically varying the visual texture of the tunnel, and the strength of headwinds experienced by the flying bees. We found that in a flight tunnel bees used visual cues to maintain their ground speed, and adjusted their air speed to maintain a constant rate of optic flow, even against headwinds which were, at their strongest, 50% of a bee's maximum recorded forward velocity. Manipulation of the visual texture revealed that headwind is compensated almost fully even when the optic flow cues are very sparse and subtle, demonstrating the robustness of this visual flight control system. We discuss these findings in the context of field observations of flying bees.
Path Diversity Improved Opportunistic Routing for Underwater Sensor Networks

PubMed Central

Wang, Haiyan; He, Ke

2018-01-01

The packets carried along a pre-defined route in underwater sensor networks are very vulnerble. Node mobility or intermittent channel availability easily leads to unreachable routing. Opportunistic routing has been proven to be a promising paradigm to design routing protocols for underwater sensor networks. It takes advantage of the broadcast nature of the wireless medium to combat packet losses and selects potential paths on the fly. Finding an appropriate forwarding candidate set is a key issue in opportunistic routing. Many existing solutions ignore the impact of candidates location distribution on packet forwarding. In this paper, a path diversity improved candidate selection strategy is applied in opportunistic routing to improve packet forwarding efficiency. It not only maximizes the packet forwarding advancements but also takes the candidate’s location distribution into account. Based on this strategy, we propose two effective routing protocols: position improved candidates selection (PICS) and position random candidates selection (PRCS). PICS employs two-hop neighbor information to make routing decisions. PRCS only uses one-hop neighbor information. Simulation results show that both PICS and PRCS can significantly improve network performance when compared with the previous solutions, in terms of packet delivery ratio, average energy consumption and end-to-end delay. PMID:29690621
Path Diversity Improved Opportunistic Routing for Underwater Sensor Networks.

PubMed

Bai, Weigang; Wang, Haiyan; He, Ke; Zhao, Ruiqin

2018-04-23

The packets carried along a pre-defined route in underwater sensor networks are very vulnerble. Node mobility or intermittent channel availability easily leads to unreachable routing. Opportunistic routing has been proven to be a promising paradigm to design routing protocols for underwater sensor networks. It takes advantage of the broadcast nature of the wireless medium to combat packet losses and selects potential paths on the fly. Finding an appropriate forwarding candidate set is a key issue in opportunistic routing. Many existing solutions ignore the impact of candidates location distribution on packet forwarding. In this paper, a path diversity improved candidate selection strategy is applied in opportunistic routing to improve packet forwarding efficiency. It not only maximizes the packet forwarding advancements but also takes the candidate’s location distribution into account. Based on this strategy, we propose two effective routing protocols: position improved candidates selection (PICS) and position random candidates selection (PRCS). PICS employs two-hop neighbor information to make routing decisions. PRCS only uses one-hop neighbor information. Simulation results show that both PICS and PRCS can significantly improve network performance when compared with the previous solutions, in terms of packet delivery ratio, average energy consumption and end-to-end delay.
Morskoy Sbornik, Supplement Number 1. Soviet Naval Digest 1971

DTIC Science & Technology

1976-06-17

recesses with a click of the lock and were submerged in the onrushing wave. Captain Khrennikov moved the en- gine control levers forward. The...designed the planes — the reconnaissance and ground-attack aircraft — and what were their capabili- ties? The MBR -2 aircraft is a flying boat...designed by G. BeriyevT Thanks to excellent seaworthiness, visibil- ity and great range, the MBR -2 was widely acclaimed by naval aviators. Maximum speed
The Evolution of Air-Sea Battle: How Army Attack/Reconnaissance Aviation Fits into the Joint Concept for Access and Maneuver in the Global Commons

DTIC Science & Technology

2016-05-13

System (MTADS) has a day TV capability to laser designate and auto track tank-sized targets at 6,000 meters and a Forward Looking Infrared (FLIR...capability to laser designate and auto track tank-sized targets at 3,500 meters. The AH-64 D/E also possesses a Fire Control Radar (FCR) that allows it...a broad spectrum of size, capacity, duration, and security. At the low end are Forward Area Refueling Equipment ( FARE ) systems. These allow CH-47
Malaysian Journal of Medical Sciences: A Step Forward towards an International Journal

PubMed Central

Ghazli, Nur Farahin; Che Annual, Norfatiha; Abdullah, Jafri Malin

2015-01-01

In 1986, the Malaysian Journal of Medical Sciences (MJMS) began as the small and newly established journal Diagnosa, established by the Universiti Sains Malaysia School of Medicine. After 28 years in the publishing industry, we have received the honor of a listing as a local journal in the Emerging Sources Citation Index (ESCI) created by Thomson Reuters (TR) to spotlight emerging high-quality scientific publications. The editorial team of MJMS looks forward to the next step in the march of progress toward the status of an international journal. PMID:28223878
Closeup view of the underside of the forward fuselage of ...

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

Close-up view of the underside of the forward fuselage of the Orbiter Discovery looking at the nose landing-gear and into the landing-gear well. The vehicle is elevated and supported by jack stands attached to the hoist attach points and the rear External Tank attach points on the propellant disconnect plate assemblies. This photo was taken inside the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
The way forward for learning disability nursing.

PubMed

Camus, Heather

This article looks at a possible future or direction for learning disability nursing. Taking into account the physical, emotional, spiritual, social, medical, dental and mental health needs of people with learning disabilities, and reports from Mencap, this article outlines the need for flexibility and innovation from within the nursing profession. One forward-thinking residential home is identified who employ their own learning disability nurse to to support the residents in achieving good health and encourage communication skills between staff and residents and to promote individual rights, choice, privacy and dignity.
Malaysian Journal of Medical Sciences: A Step Forward towards an International Journal.

PubMed

Ghazli, Nur Farahin; Che Annual, Norfatiha; Abdullah, Jafri Malin

2015-11-01

In 1986, the Malaysian Journal of Medical Sciences (MJMS) began as the small and newly established journal Diagnosa, established by the Universiti Sains Malaysia School of Medicine. After 28 years in the publishing industry, we have received the honor of a listing as a local journal in the Emerging Sources Citation Index (ESCI) created by Thomson Reuters (TR) to spotlight emerging high-quality scientific publications. The editorial team of MJMS looks forward to the next step in the march of progress toward the status of an international journal.
Breeding habitat preference of preimaginal black flies (Diptera: Simuliidae) in Peninsular Malaysia.

PubMed

Ya'cob, Zubaidah; Takaoka, Hiroyuki; Pramual, Pairot; Low, Van Lun; Sofian-Azirun, Mohd

2016-01-01

To investigate the breeding habitat preference of black flies, a comprehensive black fly survey was conducted for the first time in Peninsular Malaysia. Preimaginal black flies (pupae and larvae) were collected manually from 180 stream points encompassing northern, southern, central and east coast of the Peninsular Malaysia. A total of 47 black fly species were recorded in this study. The predominant species were Simulium trangense (36.7%) and Simulium angulistylum (33.3%). Relatively common species were Simulium cheongi (29.4%), Simulium tani (25.6%), Simulium nobile (16.2%), Simulium sheilae (14.5%) and Simulium bishopi (10.6%). Principal Component Analysis (PCA) of all stream variables revealed four PCs that accounted for 69.3% of the total intersite variance. Regression analysis revealed that high species richness is associated with larger, deeper, faster and higher discharge streams with larger streambed particles, more riparian vegetation and low pH (F=22.7, d.f.=1, 173; P<0.001). Relationship between species occurrence of seven common species (present in >10% of the sampling sites) was assessed. Forward logistic regression analysis indicated that four species were significantly related to the stream variables. S. nobile and S. tani prefer large, fast flowing streams with higher pH, large streambed particles and riparian trees. S. bishopi was commonly found at high elevation with cooler stream, low conductivity, higher conductivity and more riparian trees. In contrast, S. sheilae was negatively correlated with PC-2, thus, this species commonly found at low elevation, warmer stream with low conductivity and less riparian trees. The results of this study are consistent with previous studies from other geographic regions, which indicated that both physical and chemical stream conditions are the key factors for black fly ecology. Copyright © 2015 Elsevier B.V. All rights reserved.

Is Sustainable Remediation Now a Self-Sustaining Process? an International Progress Report

NASA Astrophysics Data System (ADS)

Smith, J. W. N.

2014-12-01

Sustainable remediation - the consideration of environmental, social and economic factors associated with soil and groundwater risk-management options, to help select the best overall solution - has been a rapidly evolving topic in recent years. The first published reference[1] to 'sustainable remediation' was in the title of a 1999 conference paper by Kearney et al., (1999), but activity really accelerated in the middle-late 2000's, with establishment of a number of collaborative sustainable remediation groups and fora, and increased publication rates in the peer reviewed literature (Fig 1). Figure 1. Journal paper publications with search term 'sustainable remediation' (SCOPUS survey, 17 July 2014) This presentation will review the international progress of sustainable remediation concept development and application in regulatory and corporate decision-making processes. It will look back at what has already been achieved, provide an update on the latest initiatives and developments, and look forward to what the future of sustainable remediation might look like. Specifically it will describe: Sustainable remediation frameworks: synergies and international collaboration; Latest guidance and tools developed by the various sustainable remediation organisations (SuRFs), including the SuRF-UK Best Management Practices and Tier 1 Briefcase; Best practice standard development by ASTM and ISO; Regulatory acceptance of sustainable remediation, including incorporation into legislation, and the NICOLE - Common Forum Joint statement on 'risk-informed and sustainable remediation' in Europe; Examples of corporate adoption of sustainable remediation principles. The presentation will conclude with a look forward to a vision of sustainable remediation in 2020.
The Cultivated Classroom.

ERIC Educational Resources Information Center

Schilder, Rosalind

1983-01-01

Teachers who follow this monthly schedule for starting and cultivating plants in their classrooms can look forward to blooms and greenery throughout the year. Advice on choosing plants, making cuttings, forcing bulbs, rooting sweet potatoes and pineapples, and holding a Mother's Day plant sale is included. (PP)
Looking Forward into the Past

ERIC Educational Resources Information Center

Lucey, Thomas A.; Giannangelo, Duane M.

2015-01-01

This article concerns the interpretation of a semester-long email mentoring correspondence related to social studies teaching between the two authors. Analysis interpreted the mentee's growth along O'Malley's stages of professional reflection. The analysis found that the mentoring process fostered the mentee's establishment of professional…
Semiannual Report: Apr 1, 2005 - Sept 30, 2005

EPA Pesticide Factsheets

Semiannual Report #EPA-350-R-05-003, Dec, 2005. We look forward to the challenges ahead as EPA and the Nation continue the effort to rebuild the Gulf States region and to safeguard our environment for us and for the generations that follow.
Stress Studies at Kennedy Space Center: a Backward and Forward Look

NASA Technical Reports Server (NTRS)

Decker, A. I.

1971-01-01

Possible relationships between occupational and other stresses on ischemic heart disease are explored. Three procedures were used: (1) double master 2-step test, (2) dynamic ECG technique using avionics equipment, and (3) submaximal stress testing with Marco bicycle ergometer.
Learning as Encounter between Self and Other

ERIC Educational Resources Information Center

Valk, John

2017-01-01

In this article, the author John Volk, professor of Worldview Studies at Renaissance College, University of New Brunswick, Fredericton, New Brunswick, Canada, looks forward toward the November 2017 Religious Education Association Conference, which is entitled "Learning in Encounter: Crossroads, Connections, Collaborations", and says that…
iss042e136094

NASA Image and Video Library

2015-01-15

ISS042e136094 (Jan 15, 2015) -- Interior view looking forward (FWD) in the Destiny U.S. Laboratory during the crew's sleep period, with the main lights turned off. The pink glow comes from the Vegetable Production System (Veggie) greenhouse, housed in the Columbus European Laboratory.
Enriching the Student Learning Experience: Linking Student Development and Organizational Perspectives

ERIC Educational Resources Information Center

King, Patricia M.

2014-01-01

Founding "About Campus" Executive Editor Patricia M. King discusses her concerns about what she sees as the unnecessary split between the institutional and the individual approach to supporting student learning and provides a forward-looking model to merge the two.
High angle of attack flying qualities criteria for longitudinal rate command systems

NASA Technical Reports Server (NTRS)

Wilson, David J.; Citurs, Kevin D.; Davidson, John B.

1994-01-01

This study was designed to investigate flying qualities requirements of alternate pitch command systems for fighter aircraft at high angle of attack. Flying qualities design guidelines have already been developed for angle of attack command systems at 30, 45, and 60 degrees angle of attack, so this research fills a similar need for rate command systems. Flying qualities tasks that require post-stall maneuvering were tested during piloted simulations in the McDonnell Douglas Aerospace Manned Air Combat Simulation facility. A generic fighter aircraft model was used to test angle of attack rate and pitch rate command systems for longitudinal gross acquisition and tracking tasks at high angle of attack. A wide range of longitudinal dynamic variations were tested at 30, 45, and 60 degrees angle of attack. Pilot comments, Cooper-Harper ratings, and pilot induced oscillation ratings were taken from five pilots from NASA, USN, CAF, and McDonnell Douglas Aerospace. This data was used to form longitudinal design guidelines for rate command systems at high angle of attack. These criteria provide control law design guidance for fighter aircraft at high angle of attack, low speed flight conditions. Additional time history analyses were conducted using the longitudinal gross acquisition data to look at potential agility measures of merit and correlate agility usage to flying qualities boundaries. This paper presents an overview of this research.
Market Assessment of Forward-Looking Turbulence Sensing Systems

NASA Technical Reports Server (NTRS)

Kauffmann, Paul; Sousa-Poza, Andres

2001-01-01

In recognition of the importance of turbulence mitigation as a tool to improve aviation safety, NASA's Aviation Safety Program developed a Turbulence Detection and Mitigation Sub-element. The objective of this effort is to develop highly reliable turbulence detection technologies for commercial transport aircraft to sense dangerous turbulence with sufficient time warning so that defensive measures can be implemented and prevent passenger and crew injuries. Current research involves three forward sensing products to improve the cockpit awareness of possible turbulence hazards. X-band radar enhancements will improve the capabilities of current weather radar to detect turbulence associated with convective activity. LIDAR (Light Detection and Ranging) is a laser-based technology that is capable of detecting turbulence in clear air. Finally, a possible Radar-LIDAR hybrid sensor is envisioned to detect the full range of convective and clear air turbulence. To support decisions relating to the development of these three forward-looking turbulence sensor technologies, the objective of this study was defined as examination of cost and implementation metrics. Tasks performed included the identification of cost factors and certification issues, the development and application of an implementation model, and the development of cost budget/targets for installing the turbulence sensor and associated software devices into the commercial transport fleet.
On the detectability of the Lense-Thirring field from rotating laboratory masses using ring laser gyroscope interferometers

NASA Astrophysics Data System (ADS)

Stedman, G. E.; Schreiber, K. U.; Bilger, H. R.

2003-07-01

The possibility of detecting the Lense-Thirring field generated by the rotating earth (also rotating laboratory masses) is reassessed in view of recent dramatic advances in the technology of ring laser gyroscopes. This possibility is very much less remote than it was a decade ago. The effect may contribute significantly to the Sagnac frequency of planned instruments. Its discrimination and detection will require an improved metrology, linking the ring to the celestial reference frame, and a fuller study of dispersion- and backscatter-induced frequency pulling. Both these requirements have been the subject of recent major progress, and our goal looks feasible.
Analysis of Droplet Size during the Ice Accumulation Phase Of Flight Testing

NASA Technical Reports Server (NTRS)

Miller, Eric James

2004-01-01

There are numerous hazards associated with air travel. One of the most serious dangers to the pilot and passengers safety is the result of flying into conditions which are conducive to the formation of ice on the surface of an aircraft. Being a pilot myself I am very aware of the dangers that Icing can pose and the effects it can have on an airplane. A couple of the missions of the Icing branch is to make flying safer with more research to increase our knowledge of how ice effects the aerodynamics of an airfoil, and to increase are knowledge of the weather for better forecasting. The Icing Branch uses three different tools to determine the aerodynamic affects that icing has on a wing. The Icing research tunnel is an efficient way to test various airfoils in a controlled setting. To make sure the data received from the wind tunnel is accurate the Icing branch conducts real flight tests with the DHC-6 Twin Otter. This makes sure that the methods used in the wind tunnel accurately model what happens on the actual aircraft. These two tools are also compared to the LEWICE code which is a program that models the ice shape that would be formed on an airfoil in the particular weather conditions that are input by the user. One benefit of LEWICE is that it is a lot cheaper to run than the wind tunnel or flight tests which make it a nice tool for engineers designing aircraft that don t have the money to spend on icing research. Using all three of these tools is a way to cross check the data received from one and check it against the other two. industries, but it is also looked at by weather analysts who are trying to improve forecasting methods. The best way to avoid the troubles of icing encounters is to not go into it in the first place. By looking over the flight data the analyst can determine which conditions will most likely lead to an icing encounter and then this information will aid forecasters when briefing the pilots on the weather conditions. am looking at the weather data from certain flights and analyzing the type of precipitation that the plane is flying through. During flight tests there is a probe on the bottom of the aircraft that gathers information on the size and shape of the particles that it is flying through. The data can then be viewed on a computer. After grouping the weather into certain groups we can then pick certain groups which we think should be analyzed farther. The goal is to remove all the ice particles because they do not contribute to the icing on an aircraft. We use a 2D analyzer which measures the droplet size and categorizes the drops into bins of certain sizes. We can then look at what the characteristics of the weather that we were flying through such as the temperature and dew point and compare this with the size of the drops that the 2D analyzer measured. We can then look at what type and shape of ice that formed on the wing during this time period. Having this data will help us to reproduce these conditions using LEWICE and the wind tunnel. Having consistency among the tests will make things more accurate. With respect to weather forecasting we will be able to learn which conditions can lead to icing. Better accuracy in weather reporting will lead to fewer run-ins with icing which will also lead to fewer accidents.
Polarizing Michelson Interferometer for Measuring Thermospheric Winds.

NASA Astrophysics Data System (ADS)

Bird, John C.

The Polarizing Atmospheric Michelson Interferometer, PAMI, a new version of the Wide Angle Michelson Interferometer, is used to measure winds in the thermosphere. In the polarizing instrument, the optical path difference is changed simply by rotating a polarizing filter external to the interferometer. This allows a very simple scanning mechanism. PAMI's general behavior has been modeled in terms of Mueller matrices providing a framework for the analysis of partial polarization states within the Michelson Interferometer (MI). A field instrument based on the above concept was designed and built. PAMI is similar to other instruments such as WAMDII (Shepherd et al., 1985) that measure thermospheric winds and temperatures, retaining the benefits of high light throughput, while offering advantages including lower cost, simplicity, and portability. PAMI was constructed from readily available components wherever possible to facilitate replacement. The instrument is highly sensitive and thus is designed to be used for field measurements at locations far from city lights. Results are shown from the AIDA observation campaign in Puerto Rico (17^circ57 ^'0^{ ''}N, 66^ circ52^'42 ^{''}W) where coordinated observations were made by PAMI along with other optical and radio measurements during April and May 1989. Intensities of the green line layer at 95 km were compared to those observed by several other instruments. For example, MORTI (Mesopause Oxygen Rotational Temperature Imager), a co-located instrument which was looking at the 94 km 867.6 nm molecular oxygen emission. MORTI and PAMI emission rates were found to show the same trends. PAMI intensities were also compared to two green-line photometers. In these comparisons the trends in observed emission rates were the same for all three instruments. On the brightest night recorded during April, the zenith emission rate reached over 400 Rayleighs; emission enhancements were sometimes related to auroral events. During the observing period of April 4 to April 11, 1989, most of the observations of the 95 km airglow were after midnight where the winds were found to be generally towards the north east at about 50 to 100 m/s. During auroral activity this wind vector always turned counterclockwise, towards the west. During the nights of May 2 and May 6 these wind vectors follow a wave-like variation in magnitude and direction. It is concluded that auroral activity changes the global circulation in a way that sometimes transports increased amounts of oxygen atoms over Arecibo. Wind comparisons were made with a Fabry-Perot interferometer operating at the same time at the Arecibo observatory, 60 km away. The agreement was generally good, with some differences in detail, in some cases, for the eastward wind component.
Looking towards gravitational wave detection

NASA Astrophysics Data System (ADS)

Barsotti, Lisa

2009-05-01

It is an exciting time in gravitational wave research. The first generation ground detectors, which aim to detect gravitational waves in the audio-frequency region, have been successfully operated at their design sensitivity. One integrated year of coincident data from the three LIGO interferometers in United States has been collected between 2005 and 2007, in partial coincidence with the two European detectors, VIRGO and GEO. All the detectors are currently being upgraded, and they will come back on-line in the next few months with a factor 2 better sensitivity. A major upgrade of LIGO and VIRGO, scheduled to happen immediately after their upcoming science runs, will bring on-line second generation detectors 4 years from now. Their sensitivity is designed to be 10 times better than the first generation detectors, resulting in an expected event rate of at least a few per year. Looking farther into the future, space-based detectors such as LISA propose to cover a lower range of frequencies which are inaccessible on Earth, enhancing the opportunity of understanding our Universe trough gravitational waves.
V/STOL Dynamics, Control, and Flying Qualities

NASA Technical Reports Server (NTRS)

Franklin, James A.

2000-01-01

This publication presents material that constituted the lectures presented by the author as part of Course AA 234, Dynamics, Control, and Flying Qualities of Vertical/Short Takeoff and Landing (V/STOL) Aircraft that was taught in the Department of Aeronautics and Astronautics at Stanford University. It covers representative operations of vertical and short takeoff and landing (V/STOL) aircraft, a discussion of the pilot's strategy in controlling these aircraft, the equations of motion pertinent to V/STOL tasks, and their application in the analysis of longitudinal and lateral-directional control in hover and forward flight. Following that development, which applies to the characteristics of the basic airframe and propulsion system, the text concludes with a discussion of the contributions of control augmentation in specific flight tasks and of the integration of modern electronic displays with these controls.
The increasing divergence of raw agricultural production from edible calories

NASA Astrophysics Data System (ADS)

Johnston, M.; Cassidy, E. S.; Ray, D. K.; Mueller, N. D.; Foley, J. A.

2012-12-01

As we look forward to 2050 and the need to dramatically increase agricultural production, we must first look to our recent past to see how changes in yields and area have helped to grow agricultural resources. However, those changes must not be viewed in a vacuum -- it is insufficient to assess advancements in agricultural productivity without converting resources to usable calories by humans and to put the supply in context of population changes. This study looks at major countries and growing regions to determine the availability of usable calories from agriculture from 1965 to 2005. We examine how rapid increases in agricultural supplies in the past have freed up resources for a growing number of non-food uses. We look at how this new competition and pressures from a changing climate might impact the resiliency of our agricultural system.
Braking Analysis For Collision Avoidance-- Autonomous Braking System Performance Modeling And Benefits Analysis

DOT National Transportation Integrated Search

1996-05-24

THIS REPORT IS AN ANALYSIS OF THE BENEFITS OF A COLLISION AVOIDANCE SYSTEM IN REDUCING REAR-END CRASHES. THE COLLISION AVOIDANCE SYSTEM CONSIDERED IN THIS STUDY UTILIZES THE SIGNAL FROM A FORWARD LOOKING SENSOR TO ACTIVATE THE TRACTION CONTROL VALVE ...
The Enterprise Compass

ERIC Educational Resources Information Center

McCardle, Ken

2005-01-01

As a CIO leading an IT department through change and reorganization, the author developed the Enterprise Compass--a four-point guide to reaching goals and focusing achievement. The Enterprise Compass directs staff to look forward to future accomplishment, back for performance assessments, across campus for better understanding of practical working…
Evaluating Urban Resilience to Climate Change: A Multi-Sector Approach (External Review Draft)

EPA Science Inventory

Climate change impacts are diverse, long-term, and not easily predictable. Adapting to climate change requires making context specific and forward-looking decisions regarding a variety of climate change impacts and vulnerabilities when the future is highly uncertain. EPA scientis...
78 FR 4100 - Connect America Fund

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-18

... submit along with their acceptance notices. Should such carriers be required to specify the technology or... Wireline Competition Bureau (Bureau) the task of developing a forward-looking cost model to determine... recently announced the availability of version one of the Connect America Cost Model, which provides the...

Some links on this page may take you to non-federal websites. Their policies may differ from this site.