3,954 research outputs found

    Paper Session II-B - Integrated Risk System

    Get PDF
    The International Space Station ISS is a complex system technically and programmatically. The Space Station must support a wide range of payloads and missions. It must be launched in many launch packages and safely assembled and operated in the harsh space environment. It is being designed and manufactured by many organizations, including the prime contractor, subcontractors, the NASA institution, and international partners. Finally, the Station has multiple customers, (e.g., the Administration, Congress, users, public, etc.) with contrasting needs and constraints. It is thus ISS strategy to proactively and systematically manage risk to help ensure Program success. The risk management process provides to the program systematic methods for identifying, analyzing, abating, and communicating risks

    Autonomous Laser-Powered Vehicle

    Get PDF
    An autonomous laser-powered vehicle designed to autonomously penetrate through ice caps of substantial (e.g., kilometers) thickness by melting a path ahead of the vehicle as it descends. A high powered laser beam is transmitted to the vehicle via an onboard bare fiber spooler. After the beam enters through the dispersion optics, the beam expands into a cavity. A radiation shield limits backscatter radiation from heating the optics. The expanded beam enters the heat exchanger and is reflected by a dispersion mirror. Forward-facing beveled circular grooves absorb the reflected radiant energy preventing the energy from being reflected back towards the optics. Microchannels along the inner circumference of the beam dump heat exchanger maximize heat transfer. Sufficient amount of fiber is wound on the fiber spooler to permit not only a descent but also to permit a sample return mission by inverting the vehicle and melting its way back to the surface

    Optical Energy Transfer and Conversion System

    Get PDF
    An optical power transfer system comprising a fiber spooler, a fiber optic rotary joint mechanically connected to the fiber spooler, and an electrical power extraction subsystem connected to the fiber optic rotary joint with an optical waveguide. Optical energy is generated at and transferred from a base station through fiber wrapped around the spooler, through the rotary joint, and ultimately to the power extraction system at a remote mobility platform for conversion to another form of energy

    Optical Energy Transfer and Conversion System

    Get PDF
    An optical energy transfer and conversion system comprising a fiber spooler and an electrical power extraction subsystem connected to the spooler with an optical waveguide. Optical energy is generated at and transferred from a base station through fiber wrapped around the spooler, and ultimately to the power extraction system at a remote mobility platform for conversion to another form of energy. The fiber spooler may reside on the remote mobility platform which may be a vehicle, or apparatus that is either self-propelled or is carried by a secondary mobility platform either on land, under the sea, in the air or in space

    Direct Laser Ice Penetration System

    Get PDF
    An optically powered system for rapid, focused heating and melting of water ice. The optical wavelength is chosen to fall in a range where transmissivity through liquid water is higher than through ice. An alternative embodiment of the invention further comprises a length of fiber optic tether between source and output to allow for motion of the melt head. A further embodiment includes probing the ice using various sensing modalities exploiting the presence of the fiber in the ice, searching for biomarkers and characterizing the radiation/light environment for subsurface habitability, including photosynthetic potential and radiation environment as a source for energy

    Optical Power Transfer System for Powering a Remote Mobility System for Multiple Missions

    Get PDF
    An optical power transfer system for powering a remote mobility system for multiple missions comprising a high power source and a chilling station connected to a laser source. The laser source transmits a high optical energy to a beam switch assembly via an optical fiber. The beam switch assembly is optically connected to actively cooled fiber spoolers. Docking stations are adapted for securing the fiber spoolers until alternatively ready for use by a remote mobility system. The remote mobility system is optically connected to the fiber spoolers and has a receiving port adapted for securing the fiber spoolers thereon. The fiber spooler transmits the optical energy to a power conversion system which converts the optical energy received to another usable form of energy. More than one power source may be used where the remote mobility system transfers from one source to another while maintaining an operational radius to each source

    A Solar and Galactic Cosmic Ray Satellite Experiment

    Get PDF
    A cosmic ray instrument for NASA's OGO-F spacecraft is described. The experiment consists of three charged particle detector systems which are designed to measure the spectra and chemical composition of galactic and solar cosmic rays over selected energy intervals. Two of the detector systems, the ¿E-Range and ¿E-¿erenkov telescopes, will measure the galactic flux and smaller solar flare fluxes, while a third detector system, the Flare telescope, will measure larger fluxes The three telescopes identify particle energy and type by various techniques. Energy loss and range, which provide the identification of protons (1 to 300 MeV), alpha particles (4 to 1200 MeV) and electrons (1 to 500 MeV), are measured in a stack of silicon solid state detectors and tungsten absorbers in the ¿E-Range telescope, while the identification of protons (350 to 1000 MeV), alpha particles (1400 to 4000 MeV) an, nuclei through oxygen is provided in the ¿E-¿erenkov telescope by energy loss measurements in silicon solid state detectors and a velocity measurement in a quartz & ¿erenkov radiator. The Flare telescope employs a double energy loss measurement in silicon detectors for the identification of protons (17 to 100 MeV) and alpha particles (70 to 400 MeV). The design of the instrument is optimized for maximum use of the available data rate with minimum weight, volume and power requirements

    Effect of Combination Folic Acid, Vitamin B6 , and Vitamin B12 Supplementation on Fracture Risk in Women: A Randomized, Controlled Trial.

    Get PDF
    Epidemiologic studies have demonstrated an association of elevated plasma homocysteine levels with greater bone resorption and fracture risk. Vitamins B12 , B6 , and folic acid are cofactors in homocysteine metabolism, and supplementation with B vitamins is effective in lowering homocysteine levels in humans. However, randomized trials of supplemental B vitamins for reduction of fracture risk have been limited. Therefore, we performed an ancillary study to the Women's Antioxidant and Folic Acid Cardiovascular Study (WAFACS), a large randomized trial of women with preexisting cardiovascular disease or three or more coronary risk factors, to test whether a daily B vitamin intervention including folic acid (2.5 mg/day), vitamin B6 (50 mg/day), and vitamin B12 (1 mg/day) reduces nonspine fracture risk over 7.3 years of treatment and follow-up. Among 4810 women, we confirmed 349 nonspine fracture cases by centralized review of medical records. In a substudy of 300 women (150 in treatment group and 150 controls) with paired plasma samples at randomization and follow-up (7.3 years later), we measured two bone turnover markers, including C-terminal cross-linking telopeptide of type I collagen (CTX) and intact type I procollagen N-propeptide (P1NP). In Cox proportional hazards models based on intention-to-treat, we found no significant effects of B vitamin supplementation on nonspine fracture risk (relative hazard = 1.08; 95% confidence interval, 0.88 to 1.34). In a nested case-cohort analysis, there were no significant effects of B vitamins on fracture risk among women with elevated plasma homocysteine levels, or low levels of vitamins B12 or B6 , or folate at baseline. Furthermore, treatment with B vitamins had no effect on change in markers of bone turnover. We found no evidence that daily supplementation with B vitamins reduces fracture risk or rates of bone metabolism in middle-aged and older women at high risk of cardiovascular disease. © 2017 American Society for Bone and Mineral Research

    Aberrant Subclavian Artery: Presentation and Outcomes

    Get PDF
    • …
    corecore