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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 523 records · Page 29

STS-113 Mission Highlights Resource Tape Flight Days 4-6 Tape: 2 of 4

This video, Part 2 of 4, shows the activities of the crew of the Space Shuttle Endeavor on flight days 4-6 of STS-113. The crew consists of Commander Jim Wetherbee, Pilot Paul Lockhart, and Mission Specialists Michael Lopez-Alegria and John Herrington. On flight day 4, The P1 truss was transfered from Canadarm on Endeavour to Canadarm 2 on the ISS, and aligned with the S0 Truss for attachment. The mission specialists connected utility cables between the trusses on an extravehicular activity (EVA). Flight day 5 was Commander Wetherbee's 50th birthday, and the video includes a clip from The Tonight Show in which Jay Leno wishes him a happy birthday. Intravehicular activity on flight day 5 includes Peggy Whitsun of the outgoing Expedition 5 crew of the International Space Station (ISS) showing incoming Expedition 6 crew members Ken Bowersox and Don Pettit how to replace valves on the ISS CO2 removal system. The video also includes an interior tour of Endeavour and the ISS, and an brief exterior tour of the ISS. On flight day 6 Lopez-Alegria and Herrington attach a television antenna to the P1 truss, and are shown using a handcart on the truss several times. The video includes several Earth views, including one of the west coast of South America.

Source record↗

Instrumentation and methodology for quantifying GFP fluorescence in intact plant organs

The General Fluorescence Plant Meter (GFP-Meter) is a portable spectrofluorometer that utilizes a fiber-optic cable and a leaf clip to gather spectrofluorescence data. In contrast to traditional analytical systems, this instrument allows for the rapid detection and fluorescence measurement of proteins under field conditions with no damage to plant tissue. Here we discuss the methodology of gathering and standardizing spectrofluorescence data from tobacco and canola plants expressing GFP. Furthermore, we demonstrate the accuracy and effectiveness of the GFP-Meter. We first compared GFP fluorescence measurements taken by the GFP-Meter to those taken by a standard laboratory-based spectrofluorometer, the FluoroMax-2. Spectrofluorescence measurements were taken from the same location on intact leaves. When these measurements were tested by simple linear regression analysis, we found that there was a positive functional relationship between instruments. Finally, to exhibit that the GFP-Meter recorded accurate measurements over a span of time, we completed a time-course analysis of GFP fluorescence measurements. We found that only initial measurements were accurate; however, subsequent measurements could be used for qualitative purposes.

Evaluation Studies↗

Effect of gravity on lung exhaled nitric oxide at rest and during exercise

Exhaled nitric oxide (NO) from the lungs (VNO) in nose-clipped subjects increases during exercise. This may be due to endothelial shear stress secondary to changes in pulmonary blood flow. We measured VNO after modifying pulmonary blood flow with head-out water immersion (WI) or increased gravity (2 Gz) at rest and during exercise. Ten sedentary males were studied during exercise performed in air and WI. Nine subjects were studied at 1 and 2 Gz. Resting NO concentrations in exhaled air ([NO]) were 16.3 +/- 8.2 ppb (air). 15 +/- 8.2 ppb (WI) and 17.4 +/- 5 ppb (2 Gz). VNO (ppb/min) was calculated as [NO]VE and was unchanged at rest by either WI or 2 Gz. VNO increased linearly with Vo2, VE and fii during exercise in air, WI and at 2 Gz. These relationships did not differ among the experimental conditions. Therefore, changes in pulmonary blood flow failed to alter the output of NO exhaled from the lungs at rest or during exercise.

Clinical Trial↗

Oceanic Tidal Mixing As a Contributor to Milankovitch-scale Climate Change

We propose that changes in the magnitude of oceanic tidal mixing on long time scales is an important, but previously unrecognized, contributor to global climate change. it is well known that Earth's orbital and rotational state changes significantly on 10(exp 4)-10(exp 5) year time scales, and that this influences the spatial and temporal pattern of incident radiation. It is widely supposed that climatic variations on these same time scales are, in large part, a response of the ocean-atmosphere-cryosphere system to this radiative forcing. Our proposal is that variations in the luni-solar tidal potential, induced by these same orbital and rotational variations, influences oceanic mixing and thus modulates meridional heat transport, by amounts which are competitive with the radiative forcing. There are some obvious differences between tidal potential and insolation. First is that the Sun and Moon both contribute to tides, whereas the radiation is entirely of solar origin. Second is that the Earth is transparent to gravity but opaque to radiation. Clipping associated with this opacity makes the radiation pattern temporal spectrum rather more complex than the tidal spectrum. A third point is that solar radiation directly delivers energy to Earth's surface whereas tidal mixing will only expedite lateral transport of heat in association with oceanic thermohaline circulation. The diurnal average insolation pattern is best parameterized via a Fourier series in time of year and Legendre polynomials in sine of latitude. Our present focus will be on the annual average terms. The Legendre degree n=0 term describes the global average insolation, and is nearly constant. The degree n=l term describes differences between northern and southern hemispheres, and the annual mean is zero. The degree n=2 term is the main contributor to the equator to pole variations, and varies with obliquity and orbital eccentricity, with the obliquity variation dominating. The lowest order decomposition of the tidal potential recognizes 3 constituents: semi-diurnal, diurnal, and long period, with solar and lunar contributions to each. Our present focus will be on long term variations in the mean square amplitude of the semi-diurnal constituent, with averaging over all the short period variations. For the solar tide that includes the day and year. For the lunar tide it includes the day, month, year, and the apsidal (8.85 year) and nodal (18.6 year) periods. We present calculations of the variations in radiative and tidal forcing for the past 3 million years. The two signals are quite similar. Both vary by approximately 1% of their respective mean values, are dominated by obliquity variations, and exhibit only secondary influence from orbital eccentricity.

Munk, Walter↗

Benchmark Testing of the Largest Titanium Aluminide Sheet Subelement Conducted

To evaluate wrought titanium aluminide (gamma TiAl) as a viable candidate material for the High-Speed Civil Transport (HSCT) exhaust nozzle, an international team led by the NASA Glenn Research Center at Lewis Field successfully fabricated and tested the largest gamma TiAl sheet structure ever manufactured. The gamma TiAl sheet structure, a 56-percent subscale divergent flap subelement, was fabricated for benchmark testing in three-point bending. Overall, the subelement was 84-cm (33-in.) long by 13-cm (5-in.) wide by 8-cm (3-in.) deep. Incorporated into the subelement were features that might be used in the fabrication of a full-scale divergent flap. These features include the use of: (1) gamma TiAl shear clips to join together sections of corrugations, (2) multiple gamma TiAl face sheets, (3) double hot-formed gamma TiAl corrugations, and (4) brazed joints. The structural integrity of the gamma TiAl sheet subelement was evaluated by conducting a room-temperature three-point static bend test.

Bartolotta, Paul A.↗

The Voyage of Exploration and Discovery: Earth-Moon, Mars and Beyond

This viewgraph is a printout of a presentation which originally contained multimedia components. The presentation summarizes the accomplishments of the Cassini-Huygens mission, with numerous images and video clips of Saturn, its rings, and its moons. The presentation also summarizes a feasibility analysis of the Neptune-Triton Explorer (NExTEP).

Esper, Jaime↗

STS-114: Mission Status Briefing

Phil Engelauf, STS-114 Mission Operations Representative; Mark Ferring, Lead ISS Flight Director; Cindy Begley, Lead Spacewalk Officer for the Mission were present. Phil reported that the vehicle continues to operate very cleanly, no system anomalies or issues, crew keeping up with the timelines, and small minor and major EVA activities went extremely well. He recapped previous day's activities such as: nitrogen transfer to the Station, and storing water and transferring it to the Space Station. Mark noted Mission Specialists Steven Robinson and Souichi Noguchi's superb job doing EVA. Cindy gave a technical detail of the CMG1 remove and replace activities with supporting video clips. News media focused their questions on technical details of flight activities and safety.

Source record↗

STS-114: Discovery Day 9 Mission Status Briefing

Paul Hill, STS-114 Lead Shuttle Flight Director; Mark Ferring, Lead ISS Flight Director; Cindy Begley, STS-114 Lead EVA Officer were present. Paul reported on the general accomplishments of the mission for the day: the transfer to two stations are complete, transfers back from station into logistics module into the mid-deck are about 75 % complete and definitely in schedule to finish the next day, everything with the external video cam and the RGMC return are complete. He noted that all crews are doing great by all means. Paul also gave a detailed explanation with supporting video clips regarding concern for Eileen's side of window. Mark and Cindy both gave technical details on Mission Specialists Steven Robinson and Souichi Noguchi's extravehicular activities (EVA). News media focused most of their questions on extravehicular activities.

Source record↗

STS-114: Discovery Mission Status Briefing (incl. Statement from Cmdr. Collins and Crew)

Commander Eileen Collins and crew briefly thanked everyone who worked hard to get the Shuttle back in space, and dedicated the mission to the Columbia crew as she bids their first "good night" to the Mission Control Room in Houston. Video continues with the Mission Status Briefing by Phil Engelauf, STS-114 Mission Operations Representative, and John Shannon, Manager of the Space Shuttle Operations and Integration. Phil noted that launching and ascent had gone extremely well, the crews and the flight control team performed well and the vehicle performed exceptionally as well. The launch is the beginning of a 12 day mission period. John details the tasks of the Engineering team processing the radar data taken during ascent and checking frame by frame the imagery from both on vehicle imagery and ground imagery. John further detailed the two debris event from ascent video clips of tile loss and an unidentified material falling off from the external tank; the release of TYVEK covers, and bird impact on the external tank nose cone. Tile shearing, tile damage, tile repair, landing gear door seals, repair capabilities, debris assessment, safety, inspections criteria, data acquisitions and data analysis were topics covered with the News media.

Source record↗

External Load Affects Ground Reaction Force Parameters Non-uniformly during Running in Weightlessness

Long-term exposure to microgravity induces detrimefits to the musculcskdetal system (Schneider et al., 1995; LeBlanc et al., 2000). Treadmill exercise is used onboard the International Space Station as an exercise countermeasure to musculoskeletal deconditioning due to spaceflight. During locomotive exercise in weightlessness (0G), crewmembers wear a harness attached to an external loading mechanism (EL). The EL pulls the crewmember toward the treadmill, and provides resistive load during the impact and propulsive phases of gait. The resulting forces may be important in stimulating bone maintenance (Turner, 1998). The EL can be applied via a bungee and carabineer clip configuration attached to the harness and can be manipulated to create varying amounts of load levels during exercise. Ground-based research performed using a vertically mounted treadmill found that peak ground reaction forces (GRF) during running at an EL of less than one body weight (BW) are less than those that occur during running in normal gravity (1G) (Davis et al., 1996). However, it is not known how the GRF are affected by the EL in a true OG environment. Locomotion while suspended may result in biomechanics that differ from free running. The purpose of this investigation was to determine how EL affects peak impact force, peak propulsive force, loading rate, and impulse of the GRF during running in 0G. It was hypothesized that increasing EL would result in increases in each GRF parameter.

DeWitt, John↗

Free Body Dynamics of a Spinning Cylinder With Planar Restraint (a.k.a. Barrel of Fun)

The dynamic motion of a cylinder on a floor or hard surface is both entertaining and instructive. With maintenance torques, motion can be sustained and controlled as illustrated in a video clip that can be viewed in the PDF file of this document. The analysis of such a cylinder with and without end caps is burned on rotation about its center of mass and restrained by a plane normal to the axis passing through its center of mass at an angle alpha. For small values of alpha, the governing equations are simplified, and for symmetric bodies, stability requires rotation greater than [2 square root of(JWL*)]/J(sub X), where J is the transverse mass moment of inertia, W is the weight of the cylinder, L* is the cylinder length from the base to the center of mass, and JX is the mass moment of inertia about the longitudinal axis OX of the barrel. Comparisons to data are made and some applications are discussed.

Moraru, Laurentiu↗

Extravehicular Activity (EVA) 101: Constellation EVA Systems

A viewgraph presentation on Extravehicular Activity (EVA) Systems is shown. The topics include: 1) Why do we need space suits? 2) Protection From the Environment; 3) Primary Life Support System (PLSS); 4) Thermal Control; 5) Communications; 6) Helmet and Extravehicular Visor Assy; 7) Hard Upper Torso (HUT) and Arm Assy; 8) Display and Controls Module (DCM); 9) Gloves; 10) Lower Torso Assembly (LTA); 11) What Size Do You Need?; 12) Boot and Sizing Insert; 13) Boot Heel Clip and Foot Restraint; 14) Advanced and Crew Escape Suit; 15) Nominal & Off-Nominal Landing; 16) Gemini Program (mid-1960s); 17) Apollo EVA on Service Module; 18) A Bold Vision for Space Exploration, Authorized by Congress; 19) EVA System Missions; 20) Configurations; 21) Reduced Gravity Program; and 22) Other Opportunities.

Jordan, Nicole C.↗

Six Decades of Flight Research: Dryden Flight Research Center, 1946 - 2006 [DVD]

This DVD contains an introduction by Center Director Kevin Peterson, two videos on the history of NASA Dryden Flight Research Center and a bibliography of NASA Dryden Flight Research Center publications from 1946 through 2006. The NASA Dryden 60th Anniversary Summary Documentary video is narrated by Michael Dorn and give a brief history of Dryden. The Six Decades of Flight Research at NASA Dryden lasts approximately 75 minutes and is broken up in six decades: 1. The Early X-Plane Era; 2. The X-15 Era; 3. The Lifting Body Era; 4. The Space Shuttle Era; 5. The High Alpha and Thrust Vectoring Era; and 6. The technology Demonstration Era. The bibliography provides citations for NASA Technical Reports and Conference Papers, Tech Briefs, Contractor Reports, UCLA Flight Systems Research Center publications and Dryden videos. Finally, a link is provided to the NASA Dryden Gallery that features video clips and photos of the many unique aircraft flown at NASA Dryden and its predecessor organizations.

Fisher, David F.↗

The James Webb Space Telescope

The James Webb Space Telescope (JWST) is a 6.6m diameter, segmented, deployable telescope for cryogenic IR space astronomy (approx.40K). The JWST Observatory architecture includes the Optical Telescope Element and the Integrated Science Instrument Module (ISIM) element that contains four science instruments (SI) including a Guider. The ISIM optical metering structure is a roughly 2.2x1.7x2.2mY, asymmetric frame that is composed of carbon fiber and resin tubes bonded to invar end fittings and composite gussets and clips. The structure supports the SIs, isolates the SIs from the OTE, and supports thermal and electrical subsystems. The structure is attached to the OTE structure via strut-like kinematic mounts. The ISM structure must meet its requirements at the approx.40K cryogenic operating temperature. The SIs are aligned to the structure s coordinate system under ambient, clean room conditions using laser tracker and theodolite metrology. The ISM structure is thermally cycled for stress relief and in order to measure temperature-induced mechanical, structural changes. These ambient-to-cryogenic changes in the alignment of SI and OTE-related interfaces are an important component in the JWST Observatory alignment plan and must be verified.

Nowak, Maria↗

Overview of Experimental Capabilities - Supersonics

This viewgraph presentation gives an overview of experimental capabilities applicable to the area of supersonic research. The contents include: 1) EC Objectives; 2) SUP.11: Elements; 3) NRA; 4) Advanced Flight Simulator Flexible Aircraft Simulation Studies; 5) Advanced Flight Simulator Flying Qualities Guideline Development for Flexible Supersonic Transport Aircraft; 6) Advanced Flight Simulator Rigid/Flex Flight Control; 7) Advanced Flight Simulator Rapid Sim Model Exchange; 8) Flight Test Capabilities Advanced In-Flight Infrared (IR) Thermography; 9) Flight Test Capabilities In-Flight Schlieren; 10) Flight Test Capabilities CLIP Flow Calibration; 11) Flight Test Capabilities PFTF Flowfield Survey; 12) Ground Test Capabilities Laser-Induced Thermal Acoustics (LITA); 13) Ground Test Capabilities Doppler Global Velocimetry (DGV); 14) Ground Test Capabilities Doppler Global Velocimetry (DGV); and 15) Ground Test Capabilities EDL Optical Measurement Capability (PIV) for Rigid/Flexible Decelerator Models.

Banks, Daniel W.↗

Edge smoothing for real-time simulation of a polygon face object system as viewed by a moving observer

The visual system within an aircraft flight simulation system receives flight data and terrain data which is formated into a buffer memory. The image data is forwarded to an image processor which translates the image data into face vertex vectors Vf, defining the position relationship between the vertices of each terrain object and the aircraft. The image processor then rotates, clips, and projects the image data into two-dimensional display vectors (Vd). A display generator receives the Vd faces, and other image data to provide analog inputs to CRT devices which provide the window displays for the simulated aircraft. The video signal to the CRT devices passes through an edge smoothing device which prolongs the rise time (and fall time) of the video data inversely as the slope of the edge being smoothed. An operational amplifier within the edge smoothing device has a plurality of independently selectable feedback capacitors each having a different value. The values of the capacitors form a series which doubles as a power of two. Each feedback capacitor has a fast switch responsive to the corresponding bit of a digital binary control word for selecting (1) or not selecting (0) that capacitor. The control word is determined by the slope of each edge. The resulting actual feedback capacitance for each edge is the sum of all the selected capacitors and is directly proportional to the value of the binary control word. The output rise time (or fall time) is a function of the feedback capacitance, and is controlled by the slope through the binary control word.

Lotz, Robert W.↗

3D Position and Velocity Vector Computations of Objects Jettisoned from the International Space Station Using Close-Range Photogrammetry Approach

Measurement of the jettisoned object departure trajectory and velocity vector in the International Space Station (ISS) reference frame is vitally important for prompt evaluation of the object s imminent orbit. We report on the first successful application of photogrammetric analysis of the ISS imagery for the prompt computation of the jettisoned object s position and velocity vectors. As post-EVA analyses examples, we present the Floating Potential Probe (FPP) and the Russian "Orlan" Space Suit jettisons, as well as the near-real-time (provided in several hours after the separation) computations of the Video Stanchion Support Assembly Flight Support Assembly (VSSA-FSA) and Early Ammonia Servicer (EAS) jettisons during the US astronauts space-walk. Standard close-range photogrammetry analysis was used during this EVA to analyze two on-board camera image sequences down-linked from the ISS. In this approach the ISS camera orientations were computed from known coordinates of several reference points on the ISS hardware. Then the position of the jettisoned object for each time-frame was computed from its image in each frame of the video-clips. In another, "quick-look" approach used in near-real time, orientation of the cameras was computed from their position (from the ISS CAD model) and operational data (pan and tilt) then location of the jettisoned object was calculated only for several frames of the two synchronized movies. Keywords: Photogrammetry, International Space Station, jettisons, image analysis.

Papanyan, Valeri↗

MISR Browse data (MISBR_V3)

A MISR Browse Tool is available to allow easy access to ellipsoid-derived, true-color images for each camera reduced to 2.2 km resolution. The MISR red, green and blue bands are used to create the true-color image in JPEG format. The image is intentionally clipped and gamma-stretched to make cloud, ocean and land features visible. The user may find the Browse Tool helpful before ordering data. The tool's purpose is to search and view images in the on-line user interface. However, the browse product can be ordered separately. The Browse Tool page has Orbit-to-Date and Lat/Lon-to-Path/Block conversion tools to help identify particular MISR geographic locations and data files. [Location=GLOBAL] [Temporal_Coverage: Start_Date=2000-02-24; Stop_Date=] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.2 km; Longitude_Resolution=2.2 km; Horizontal_Resolution_Range=1 km - < 10 km or approximately .01 degree - < .09 degree; Temporal_Resolution=about 15 orbits/day; Temporal_Resolution_Range=Daily - < Weekly].

EOSDIS↗